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Commit | Line | Data |
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1da177e4 LT |
1 | /* i2c-core.c - a device driver for the iic-bus interface */ |
2 | /* ------------------------------------------------------------------------- */ | |
3 | /* Copyright (C) 1995-99 Simon G. Vogl | |
4 | ||
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License as published by | |
7 | the Free Software Foundation; either version 2 of the License, or | |
8 | (at your option) any later version. | |
9 | ||
10 | This program is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
ca1f8da9 | 13 | GNU General Public License for more details. */ |
1da177e4 LT |
14 | /* ------------------------------------------------------------------------- */ |
15 | ||
96de0e25 | 16 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. |
1da177e4 | 17 | All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> |
421ef47b | 18 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
7c81c60f | 19 | Jean Delvare <jdelvare@suse.de> |
0826374b | 20 | Mux support by Rodolfo Giometti <giometti@enneenne.com> and |
687b81d0 WS |
21 | Michael Lawnick <michael.lawnick.ext@nsn.com> |
22 | OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de> | |
23 | (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and | |
24 | (c) 2013 Wolfram Sang <wsa@the-dreams.de> | |
17f4a5c4 WS |
25 | I2C ACPI code Copyright (C) 2014 Intel Corp |
26 | Author: Lan Tianyu <tianyu.lan@intel.com> | |
4b1acc43 | 27 | I2C slave support (c) 2014 by Wolfram Sang <wsa@sang-engineering.com> |
687b81d0 | 28 | */ |
1da177e4 | 29 | |
b4e2f6ac | 30 | #include <dt-bindings/i2c/i2c.h> |
53feedf8 WS |
31 | #include <asm/uaccess.h> |
32 | #include <linux/acpi.h> | |
33 | #include <linux/clk/clk-conf.h> | |
34 | #include <linux/completion.h> | |
5f9296ba | 35 | #include <linux/delay.h> |
53feedf8 | 36 | #include <linux/err.h> |
1da177e4 | 37 | #include <linux/errno.h> |
5f9296ba | 38 | #include <linux/gpio.h> |
53feedf8 | 39 | #include <linux/hardirq.h> |
1da177e4 | 40 | #include <linux/i2c.h> |
1da177e4 | 41 | #include <linux/idr.h> |
53feedf8 WS |
42 | #include <linux/init.h> |
43 | #include <linux/irqflags.h> | |
44 | #include <linux/jump_label.h> | |
45 | #include <linux/kernel.h> | |
46 | #include <linux/module.h> | |
b3585e4f | 47 | #include <linux/mutex.h> |
959e85f7 | 48 | #include <linux/of_device.h> |
53feedf8 | 49 | #include <linux/of.h> |
687b81d0 | 50 | #include <linux/of_irq.h> |
f48c767c | 51 | #include <linux/pm_domain.h> |
53feedf8 | 52 | #include <linux/pm_runtime.h> |
3fffd128 | 53 | #include <linux/pm_wakeirq.h> |
e1dba01c | 54 | #include <linux/property.h> |
53feedf8 WS |
55 | #include <linux/rwsem.h> |
56 | #include <linux/slab.h> | |
1da177e4 | 57 | |
9c1600ed DB |
58 | #include "i2c-core.h" |
59 | ||
d9a83d62 DH |
60 | #define CREATE_TRACE_POINTS |
61 | #include <trace/events/i2c.h> | |
1da177e4 | 62 | |
da899f55 WS |
63 | #define I2C_ADDR_OFFSET_TEN_BIT 0xa000 |
64 | #define I2C_ADDR_OFFSET_SLAVE 0x1000 | |
65 | ||
6629dcff | 66 | /* core_lock protects i2c_adapter_idr, and guarantees |
35fc37f8 | 67 | that device detection, deletion of detected devices, and attach_adapter |
19baba4c | 68 | calls are serialized */ |
caada32a | 69 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
70 | static DEFINE_IDR(i2c_adapter_idr); |
71 | ||
4f8cf824 | 72 | static struct device_type i2c_client_type; |
4735c98f | 73 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
f37dd80a | 74 | |
d9a83d62 | 75 | static struct static_key i2c_trace_msg = STATIC_KEY_INIT_FALSE; |
95026658 | 76 | static bool is_registered; |
d9a83d62 DH |
77 | |
78 | void i2c_transfer_trace_reg(void) | |
79 | { | |
80 | static_key_slow_inc(&i2c_trace_msg); | |
81 | } | |
82 | ||
83 | void i2c_transfer_trace_unreg(void) | |
84 | { | |
85 | static_key_slow_dec(&i2c_trace_msg); | |
86 | } | |
87 | ||
17f4a5c4 WS |
88 | #if defined(CONFIG_ACPI) |
89 | struct acpi_i2c_handler_data { | |
90 | struct acpi_connection_info info; | |
91 | struct i2c_adapter *adapter; | |
92 | }; | |
93 | ||
94 | struct gsb_buffer { | |
95 | u8 status; | |
96 | u8 len; | |
97 | union { | |
98 | u16 wdata; | |
99 | u8 bdata; | |
100 | u8 data[0]; | |
101 | }; | |
102 | } __packed; | |
103 | ||
166c2ba3 MW |
104 | struct acpi_i2c_lookup { |
105 | struct i2c_board_info *info; | |
106 | acpi_handle adapter_handle; | |
107 | acpi_handle device_handle; | |
108 | }; | |
17f4a5c4 | 109 | |
166c2ba3 MW |
110 | static int acpi_i2c_find_address(struct acpi_resource *ares, void *data) |
111 | { | |
112 | struct acpi_i2c_lookup *lookup = data; | |
113 | struct i2c_board_info *info = lookup->info; | |
114 | struct acpi_resource_i2c_serialbus *sb; | |
115 | acpi_handle adapter_handle; | |
116 | acpi_status status; | |
17f4a5c4 | 117 | |
166c2ba3 MW |
118 | if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) |
119 | return 1; | |
120 | ||
121 | sb = &ares->data.i2c_serial_bus; | |
122 | if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) | |
123 | return 1; | |
124 | ||
125 | /* | |
126 | * Extract the ResourceSource and make sure that the handle matches | |
127 | * with the I2C adapter handle. | |
128 | */ | |
129 | status = acpi_get_handle(lookup->device_handle, | |
130 | sb->resource_source.string_ptr, | |
131 | &adapter_handle); | |
132 | if (ACPI_SUCCESS(status) && adapter_handle == lookup->adapter_handle) { | |
133 | info->addr = sb->slave_address; | |
134 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) | |
135 | info->flags |= I2C_CLIENT_TEN; | |
17f4a5c4 WS |
136 | } |
137 | ||
17f4a5c4 WS |
138 | return 1; |
139 | } | |
140 | ||
141 | static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level, | |
142 | void *data, void **return_value) | |
143 | { | |
144 | struct i2c_adapter *adapter = data; | |
145 | struct list_head resource_list; | |
166c2ba3 MW |
146 | struct acpi_i2c_lookup lookup; |
147 | struct resource_entry *entry; | |
17f4a5c4 WS |
148 | struct i2c_board_info info; |
149 | struct acpi_device *adev; | |
150 | int ret; | |
151 | ||
152 | if (acpi_bus_get_device(handle, &adev)) | |
153 | return AE_OK; | |
154 | if (acpi_bus_get_status(adev) || !adev->status.present) | |
155 | return AE_OK; | |
156 | ||
157 | memset(&info, 0, sizeof(info)); | |
ce793486 | 158 | info.fwnode = acpi_fwnode_handle(adev); |
17f4a5c4 | 159 | |
166c2ba3 | 160 | memset(&lookup, 0, sizeof(lookup)); |
8eb5c87a | 161 | lookup.adapter_handle = ACPI_HANDLE(&adapter->dev); |
166c2ba3 MW |
162 | lookup.device_handle = handle; |
163 | lookup.info = &info; | |
164 | ||
165 | /* | |
166 | * Look up for I2cSerialBus resource with ResourceSource that | |
167 | * matches with this adapter. | |
168 | */ | |
17f4a5c4 WS |
169 | INIT_LIST_HEAD(&resource_list); |
170 | ret = acpi_dev_get_resources(adev, &resource_list, | |
166c2ba3 | 171 | acpi_i2c_find_address, &lookup); |
17f4a5c4 WS |
172 | acpi_dev_free_resource_list(&resource_list); |
173 | ||
174 | if (ret < 0 || !info.addr) | |
175 | return AE_OK; | |
176 | ||
166c2ba3 MW |
177 | /* Then fill IRQ number if any */ |
178 | ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); | |
179 | if (ret < 0) | |
180 | return AE_OK; | |
181 | ||
182 | resource_list_for_each_entry(entry, &resource_list) { | |
183 | if (resource_type(entry->res) == IORESOURCE_IRQ) { | |
184 | info.irq = entry->res->start; | |
185 | break; | |
186 | } | |
187 | } | |
188 | ||
189 | acpi_dev_free_resource_list(&resource_list); | |
190 | ||
17f4a5c4 WS |
191 | adev->power.flags.ignore_parent = true; |
192 | strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type)); | |
193 | if (!i2c_new_device(adapter, &info)) { | |
194 | adev->power.flags.ignore_parent = false; | |
195 | dev_err(&adapter->dev, | |
196 | "failed to add I2C device %s from ACPI\n", | |
197 | dev_name(&adev->dev)); | |
198 | } | |
199 | ||
200 | return AE_OK; | |
201 | } | |
202 | ||
166c2ba3 MW |
203 | #define ACPI_I2C_MAX_SCAN_DEPTH 32 |
204 | ||
17f4a5c4 WS |
205 | /** |
206 | * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter | |
207 | * @adap: pointer to adapter | |
208 | * | |
209 | * Enumerate all I2C slave devices behind this adapter by walking the ACPI | |
210 | * namespace. When a device is found it will be added to the Linux device | |
211 | * model and bound to the corresponding ACPI handle. | |
212 | */ | |
213 | static void acpi_i2c_register_devices(struct i2c_adapter *adap) | |
214 | { | |
17f4a5c4 WS |
215 | acpi_status status; |
216 | ||
8eb5c87a | 217 | if (!has_acpi_companion(&adap->dev)) |
17f4a5c4 WS |
218 | return; |
219 | ||
166c2ba3 MW |
220 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, |
221 | ACPI_I2C_MAX_SCAN_DEPTH, | |
17f4a5c4 WS |
222 | acpi_i2c_add_device, NULL, |
223 | adap, NULL); | |
224 | if (ACPI_FAILURE(status)) | |
225 | dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); | |
226 | } | |
227 | ||
228 | #else /* CONFIG_ACPI */ | |
229 | static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { } | |
230 | #endif /* CONFIG_ACPI */ | |
231 | ||
232 | #ifdef CONFIG_ACPI_I2C_OPREGION | |
233 | static int acpi_gsb_i2c_read_bytes(struct i2c_client *client, | |
234 | u8 cmd, u8 *data, u8 data_len) | |
235 | { | |
236 | ||
237 | struct i2c_msg msgs[2]; | |
238 | int ret; | |
239 | u8 *buffer; | |
240 | ||
241 | buffer = kzalloc(data_len, GFP_KERNEL); | |
242 | if (!buffer) | |
243 | return AE_NO_MEMORY; | |
244 | ||
245 | msgs[0].addr = client->addr; | |
246 | msgs[0].flags = client->flags; | |
247 | msgs[0].len = 1; | |
248 | msgs[0].buf = &cmd; | |
249 | ||
250 | msgs[1].addr = client->addr; | |
251 | msgs[1].flags = client->flags | I2C_M_RD; | |
252 | msgs[1].len = data_len; | |
253 | msgs[1].buf = buffer; | |
254 | ||
255 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); | |
256 | if (ret < 0) | |
257 | dev_err(&client->adapter->dev, "i2c read failed\n"); | |
258 | else | |
259 | memcpy(data, buffer, data_len); | |
260 | ||
261 | kfree(buffer); | |
262 | return ret; | |
263 | } | |
264 | ||
265 | static int acpi_gsb_i2c_write_bytes(struct i2c_client *client, | |
266 | u8 cmd, u8 *data, u8 data_len) | |
267 | { | |
268 | ||
269 | struct i2c_msg msgs[1]; | |
270 | u8 *buffer; | |
271 | int ret = AE_OK; | |
272 | ||
273 | buffer = kzalloc(data_len + 1, GFP_KERNEL); | |
274 | if (!buffer) | |
275 | return AE_NO_MEMORY; | |
276 | ||
277 | buffer[0] = cmd; | |
278 | memcpy(buffer + 1, data, data_len); | |
279 | ||
280 | msgs[0].addr = client->addr; | |
281 | msgs[0].flags = client->flags; | |
282 | msgs[0].len = data_len + 1; | |
283 | msgs[0].buf = buffer; | |
284 | ||
285 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); | |
286 | if (ret < 0) | |
287 | dev_err(&client->adapter->dev, "i2c write failed\n"); | |
288 | ||
289 | kfree(buffer); | |
290 | return ret; | |
291 | } | |
292 | ||
293 | static acpi_status | |
294 | acpi_i2c_space_handler(u32 function, acpi_physical_address command, | |
295 | u32 bits, u64 *value64, | |
296 | void *handler_context, void *region_context) | |
297 | { | |
298 | struct gsb_buffer *gsb = (struct gsb_buffer *)value64; | |
299 | struct acpi_i2c_handler_data *data = handler_context; | |
300 | struct acpi_connection_info *info = &data->info; | |
301 | struct acpi_resource_i2c_serialbus *sb; | |
302 | struct i2c_adapter *adapter = data->adapter; | |
7ef85f5f | 303 | struct i2c_client *client; |
17f4a5c4 WS |
304 | struct acpi_resource *ares; |
305 | u32 accessor_type = function >> 16; | |
306 | u8 action = function & ACPI_IO_MASK; | |
4470c725 | 307 | acpi_status ret; |
17f4a5c4 WS |
308 | int status; |
309 | ||
310 | ret = acpi_buffer_to_resource(info->connection, info->length, &ares); | |
311 | if (ACPI_FAILURE(ret)) | |
312 | return ret; | |
313 | ||
7ef85f5f JN |
314 | client = kzalloc(sizeof(*client), GFP_KERNEL); |
315 | if (!client) { | |
316 | ret = AE_NO_MEMORY; | |
317 | goto err; | |
318 | } | |
319 | ||
17f4a5c4 WS |
320 | if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) { |
321 | ret = AE_BAD_PARAMETER; | |
322 | goto err; | |
323 | } | |
324 | ||
325 | sb = &ares->data.i2c_serial_bus; | |
326 | if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) { | |
327 | ret = AE_BAD_PARAMETER; | |
328 | goto err; | |
329 | } | |
330 | ||
7ef85f5f JN |
331 | client->adapter = adapter; |
332 | client->addr = sb->slave_address; | |
17f4a5c4 WS |
333 | |
334 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) | |
7ef85f5f | 335 | client->flags |= I2C_CLIENT_TEN; |
17f4a5c4 WS |
336 | |
337 | switch (accessor_type) { | |
338 | case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV: | |
339 | if (action == ACPI_READ) { | |
7ef85f5f | 340 | status = i2c_smbus_read_byte(client); |
17f4a5c4 WS |
341 | if (status >= 0) { |
342 | gsb->bdata = status; | |
343 | status = 0; | |
344 | } | |
345 | } else { | |
7ef85f5f | 346 | status = i2c_smbus_write_byte(client, gsb->bdata); |
17f4a5c4 WS |
347 | } |
348 | break; | |
349 | ||
350 | case ACPI_GSB_ACCESS_ATTRIB_BYTE: | |
351 | if (action == ACPI_READ) { | |
7ef85f5f | 352 | status = i2c_smbus_read_byte_data(client, command); |
17f4a5c4 WS |
353 | if (status >= 0) { |
354 | gsb->bdata = status; | |
355 | status = 0; | |
356 | } | |
357 | } else { | |
7ef85f5f | 358 | status = i2c_smbus_write_byte_data(client, command, |
17f4a5c4 WS |
359 | gsb->bdata); |
360 | } | |
361 | break; | |
362 | ||
363 | case ACPI_GSB_ACCESS_ATTRIB_WORD: | |
364 | if (action == ACPI_READ) { | |
7ef85f5f | 365 | status = i2c_smbus_read_word_data(client, command); |
17f4a5c4 WS |
366 | if (status >= 0) { |
367 | gsb->wdata = status; | |
368 | status = 0; | |
369 | } | |
370 | } else { | |
7ef85f5f | 371 | status = i2c_smbus_write_word_data(client, command, |
17f4a5c4 WS |
372 | gsb->wdata); |
373 | } | |
374 | break; | |
375 | ||
376 | case ACPI_GSB_ACCESS_ATTRIB_BLOCK: | |
377 | if (action == ACPI_READ) { | |
7ef85f5f | 378 | status = i2c_smbus_read_block_data(client, command, |
17f4a5c4 WS |
379 | gsb->data); |
380 | if (status >= 0) { | |
381 | gsb->len = status; | |
382 | status = 0; | |
383 | } | |
384 | } else { | |
7ef85f5f | 385 | status = i2c_smbus_write_block_data(client, command, |
17f4a5c4 WS |
386 | gsb->len, gsb->data); |
387 | } | |
388 | break; | |
389 | ||
390 | case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE: | |
391 | if (action == ACPI_READ) { | |
7ef85f5f | 392 | status = acpi_gsb_i2c_read_bytes(client, command, |
17f4a5c4 WS |
393 | gsb->data, info->access_length); |
394 | if (status > 0) | |
395 | status = 0; | |
396 | } else { | |
7ef85f5f | 397 | status = acpi_gsb_i2c_write_bytes(client, command, |
17f4a5c4 WS |
398 | gsb->data, info->access_length); |
399 | } | |
400 | break; | |
401 | ||
402 | default: | |
403 | pr_info("protocol(0x%02x) is not supported.\n", accessor_type); | |
404 | ret = AE_BAD_PARAMETER; | |
405 | goto err; | |
406 | } | |
407 | ||
408 | gsb->status = status; | |
409 | ||
410 | err: | |
7ef85f5f | 411 | kfree(client); |
17f4a5c4 WS |
412 | ACPI_FREE(ares); |
413 | return ret; | |
414 | } | |
415 | ||
416 | ||
417 | static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) | |
418 | { | |
0aef44e8 | 419 | acpi_handle handle; |
17f4a5c4 WS |
420 | struct acpi_i2c_handler_data *data; |
421 | acpi_status status; | |
422 | ||
0aef44e8 PH |
423 | if (!adapter->dev.parent) |
424 | return -ENODEV; | |
425 | ||
426 | handle = ACPI_HANDLE(adapter->dev.parent); | |
427 | ||
17f4a5c4 WS |
428 | if (!handle) |
429 | return -ENODEV; | |
430 | ||
431 | data = kzalloc(sizeof(struct acpi_i2c_handler_data), | |
432 | GFP_KERNEL); | |
433 | if (!data) | |
434 | return -ENOMEM; | |
435 | ||
436 | data->adapter = adapter; | |
437 | status = acpi_bus_attach_private_data(handle, (void *)data); | |
438 | if (ACPI_FAILURE(status)) { | |
439 | kfree(data); | |
440 | return -ENOMEM; | |
441 | } | |
442 | ||
443 | status = acpi_install_address_space_handler(handle, | |
444 | ACPI_ADR_SPACE_GSBUS, | |
445 | &acpi_i2c_space_handler, | |
446 | NULL, | |
447 | data); | |
448 | if (ACPI_FAILURE(status)) { | |
449 | dev_err(&adapter->dev, "Error installing i2c space handler\n"); | |
450 | acpi_bus_detach_private_data(handle); | |
451 | kfree(data); | |
452 | return -ENOMEM; | |
453 | } | |
454 | ||
40e7fcb1 | 455 | acpi_walk_dep_device_list(handle); |
17f4a5c4 WS |
456 | return 0; |
457 | } | |
458 | ||
459 | static void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) | |
460 | { | |
0aef44e8 | 461 | acpi_handle handle; |
17f4a5c4 WS |
462 | struct acpi_i2c_handler_data *data; |
463 | acpi_status status; | |
464 | ||
0aef44e8 PH |
465 | if (!adapter->dev.parent) |
466 | return; | |
467 | ||
468 | handle = ACPI_HANDLE(adapter->dev.parent); | |
469 | ||
17f4a5c4 WS |
470 | if (!handle) |
471 | return; | |
472 | ||
473 | acpi_remove_address_space_handler(handle, | |
474 | ACPI_ADR_SPACE_GSBUS, | |
475 | &acpi_i2c_space_handler); | |
476 | ||
477 | status = acpi_bus_get_private_data(handle, (void **)&data); | |
478 | if (ACPI_SUCCESS(status)) | |
479 | kfree(data); | |
480 | ||
481 | acpi_bus_detach_private_data(handle); | |
482 | } | |
483 | #else /* CONFIG_ACPI_I2C_OPREGION */ | |
484 | static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) | |
485 | { } | |
486 | ||
487 | static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) | |
488 | { return 0; } | |
489 | #endif /* CONFIG_ACPI_I2C_OPREGION */ | |
490 | ||
f37dd80a DB |
491 | /* ------------------------------------------------------------------------- */ |
492 | ||
d2653e92 JD |
493 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
494 | const struct i2c_client *client) | |
495 | { | |
496 | while (id->name[0]) { | |
497 | if (strcmp(client->name, id->name) == 0) | |
498 | return id; | |
499 | id++; | |
500 | } | |
501 | return NULL; | |
502 | } | |
503 | ||
1da177e4 LT |
504 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
505 | { | |
51298d12 JD |
506 | struct i2c_client *client = i2c_verify_client(dev); |
507 | struct i2c_driver *driver; | |
508 | ||
509 | if (!client) | |
510 | return 0; | |
7b4fbc50 | 511 | |
959e85f7 GL |
512 | /* Attempt an OF style match */ |
513 | if (of_driver_match_device(dev, drv)) | |
514 | return 1; | |
515 | ||
907ddf89 MW |
516 | /* Then ACPI style match */ |
517 | if (acpi_driver_match_device(dev, drv)) | |
518 | return 1; | |
519 | ||
51298d12 | 520 | driver = to_i2c_driver(drv); |
d2653e92 JD |
521 | /* match on an id table if there is one */ |
522 | if (driver->id_table) | |
523 | return i2c_match_id(driver->id_table, client) != NULL; | |
524 | ||
eb8a7908 | 525 | return 0; |
1da177e4 LT |
526 | } |
527 | ||
7eff2e7a | 528 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 | 529 | { |
8dcf3217 | 530 | struct i2c_client *client = to_i2c_client(dev); |
8c4ff6d0 ZR |
531 | int rc; |
532 | ||
533 | rc = acpi_device_uevent_modalias(dev, env); | |
534 | if (rc != -ENODEV) | |
535 | return rc; | |
7b4fbc50 | 536 | |
8dcf3217 | 537 | return add_uevent_var(env, "MODALIAS=%s%s", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 DB |
538 | } |
539 | ||
5f9296ba VK |
540 | /* i2c bus recovery routines */ |
541 | static int get_scl_gpio_value(struct i2c_adapter *adap) | |
542 | { | |
543 | return gpio_get_value(adap->bus_recovery_info->scl_gpio); | |
544 | } | |
545 | ||
546 | static void set_scl_gpio_value(struct i2c_adapter *adap, int val) | |
547 | { | |
548 | gpio_set_value(adap->bus_recovery_info->scl_gpio, val); | |
549 | } | |
550 | ||
551 | static int get_sda_gpio_value(struct i2c_adapter *adap) | |
552 | { | |
553 | return gpio_get_value(adap->bus_recovery_info->sda_gpio); | |
554 | } | |
555 | ||
556 | static int i2c_get_gpios_for_recovery(struct i2c_adapter *adap) | |
557 | { | |
558 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
559 | struct device *dev = &adap->dev; | |
560 | int ret = 0; | |
561 | ||
562 | ret = gpio_request_one(bri->scl_gpio, GPIOF_OPEN_DRAIN | | |
563 | GPIOF_OUT_INIT_HIGH, "i2c-scl"); | |
564 | if (ret) { | |
565 | dev_warn(dev, "Can't get SCL gpio: %d\n", bri->scl_gpio); | |
566 | return ret; | |
567 | } | |
568 | ||
569 | if (bri->get_sda) { | |
570 | if (gpio_request_one(bri->sda_gpio, GPIOF_IN, "i2c-sda")) { | |
571 | /* work without SDA polling */ | |
572 | dev_warn(dev, "Can't get SDA gpio: %d. Not using SDA polling\n", | |
573 | bri->sda_gpio); | |
574 | bri->get_sda = NULL; | |
575 | } | |
576 | } | |
577 | ||
578 | return ret; | |
579 | } | |
580 | ||
581 | static void i2c_put_gpios_for_recovery(struct i2c_adapter *adap) | |
582 | { | |
583 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
584 | ||
585 | if (bri->get_sda) | |
586 | gpio_free(bri->sda_gpio); | |
587 | ||
588 | gpio_free(bri->scl_gpio); | |
589 | } | |
590 | ||
591 | /* | |
592 | * We are generating clock pulses. ndelay() determines durating of clk pulses. | |
593 | * We will generate clock with rate 100 KHz and so duration of both clock levels | |
594 | * is: delay in ns = (10^6 / 100) / 2 | |
595 | */ | |
596 | #define RECOVERY_NDELAY 5000 | |
597 | #define RECOVERY_CLK_CNT 9 | |
598 | ||
599 | static int i2c_generic_recovery(struct i2c_adapter *adap) | |
600 | { | |
601 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
602 | int i = 0, val = 1, ret = 0; | |
603 | ||
604 | if (bri->prepare_recovery) | |
2b2190a3 | 605 | bri->prepare_recovery(adap); |
5f9296ba | 606 | |
8b062608 JL |
607 | bri->set_scl(adap, val); |
608 | ndelay(RECOVERY_NDELAY); | |
609 | ||
5f9296ba VK |
610 | /* |
611 | * By this time SCL is high, as we need to give 9 falling-rising edges | |
612 | */ | |
613 | while (i++ < RECOVERY_CLK_CNT * 2) { | |
614 | if (val) { | |
615 | /* Break if SDA is high */ | |
616 | if (bri->get_sda && bri->get_sda(adap)) | |
617 | break; | |
618 | /* SCL shouldn't be low here */ | |
619 | if (!bri->get_scl(adap)) { | |
620 | dev_err(&adap->dev, | |
621 | "SCL is stuck low, exit recovery\n"); | |
622 | ret = -EBUSY; | |
623 | break; | |
624 | } | |
625 | } | |
626 | ||
627 | val = !val; | |
628 | bri->set_scl(adap, val); | |
629 | ndelay(RECOVERY_NDELAY); | |
630 | } | |
631 | ||
632 | if (bri->unprepare_recovery) | |
2b2190a3 | 633 | bri->unprepare_recovery(adap); |
5f9296ba VK |
634 | |
635 | return ret; | |
636 | } | |
637 | ||
638 | int i2c_generic_scl_recovery(struct i2c_adapter *adap) | |
639 | { | |
5f9296ba VK |
640 | return i2c_generic_recovery(adap); |
641 | } | |
c1c21f4e | 642 | EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery); |
5f9296ba VK |
643 | |
644 | int i2c_generic_gpio_recovery(struct i2c_adapter *adap) | |
645 | { | |
646 | int ret; | |
647 | ||
648 | ret = i2c_get_gpios_for_recovery(adap); | |
649 | if (ret) | |
650 | return ret; | |
651 | ||
652 | ret = i2c_generic_recovery(adap); | |
653 | i2c_put_gpios_for_recovery(adap); | |
654 | ||
655 | return ret; | |
656 | } | |
c1c21f4e | 657 | EXPORT_SYMBOL_GPL(i2c_generic_gpio_recovery); |
5f9296ba VK |
658 | |
659 | int i2c_recover_bus(struct i2c_adapter *adap) | |
660 | { | |
661 | if (!adap->bus_recovery_info) | |
662 | return -EOPNOTSUPP; | |
663 | ||
664 | dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); | |
665 | return adap->bus_recovery_info->recover_bus(adap); | |
666 | } | |
c1c21f4e | 667 | EXPORT_SYMBOL_GPL(i2c_recover_bus); |
5f9296ba | 668 | |
f37dd80a | 669 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 670 | { |
51298d12 JD |
671 | struct i2c_client *client = i2c_verify_client(dev); |
672 | struct i2c_driver *driver; | |
50c3304a | 673 | int status; |
7b4fbc50 | 674 | |
51298d12 JD |
675 | if (!client) |
676 | return 0; | |
677 | ||
845c8770 MW |
678 | if (!client->irq) { |
679 | int irq = -ENOENT; | |
680 | ||
3fffd128 DT |
681 | if (dev->of_node) { |
682 | irq = of_irq_get_byname(dev->of_node, "irq"); | |
683 | if (irq == -EINVAL || irq == -ENODATA) | |
684 | irq = of_irq_get(dev->of_node, 0); | |
685 | } else if (ACPI_COMPANION(dev)) { | |
845c8770 | 686 | irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0); |
3fffd128 | 687 | } |
6f34be74 | 688 | if (irq == -EPROBE_DEFER) |
2fd36c55 | 689 | return irq; |
6f34be74 GU |
690 | if (irq < 0) |
691 | irq = 0; | |
2fd36c55 LP |
692 | |
693 | client->irq = irq; | |
694 | } | |
695 | ||
51298d12 | 696 | driver = to_i2c_driver(dev->driver); |
e0457442 | 697 | if (!driver->probe || !driver->id_table) |
7b4fbc50 | 698 | return -ENODEV; |
0acc2b32 | 699 | |
3fffd128 DT |
700 | if (client->flags & I2C_CLIENT_WAKE) { |
701 | int wakeirq = -ENOENT; | |
702 | ||
703 | if (dev->of_node) { | |
704 | wakeirq = of_irq_get_byname(dev->of_node, "wakeup"); | |
705 | if (wakeirq == -EPROBE_DEFER) | |
706 | return wakeirq; | |
707 | } | |
708 | ||
709 | device_init_wakeup(&client->dev, true); | |
710 | ||
711 | if (wakeirq > 0 && wakeirq != client->irq) | |
712 | status = dev_pm_set_dedicated_wake_irq(dev, wakeirq); | |
713 | else if (client->irq > 0) | |
c18fba23 | 714 | status = dev_pm_set_wake_irq(dev, client->irq); |
3fffd128 DT |
715 | else |
716 | status = 0; | |
717 | ||
718 | if (status) | |
719 | dev_warn(&client->dev, "failed to set up wakeup irq"); | |
720 | } | |
721 | ||
7b4fbc50 | 722 | dev_dbg(dev, "probe\n"); |
d2653e92 | 723 | |
86be408b SN |
724 | status = of_clk_set_defaults(dev->of_node, false); |
725 | if (status < 0) | |
3fffd128 | 726 | goto err_clear_wakeup_irq; |
86be408b | 727 | |
e09b0d4e | 728 | status = dev_pm_domain_attach(&client->dev, true); |
74cedd30 KB |
729 | if (status == -EPROBE_DEFER) |
730 | goto err_clear_wakeup_irq; | |
731 | ||
732 | status = driver->probe(client, i2c_match_id(driver->id_table, client)); | |
733 | if (status) | |
734 | goto err_detach_pm_domain; | |
72fa818e | 735 | |
3fffd128 DT |
736 | return 0; |
737 | ||
738 | err_detach_pm_domain: | |
739 | dev_pm_domain_detach(&client->dev, true); | |
740 | err_clear_wakeup_irq: | |
741 | dev_pm_clear_wake_irq(&client->dev); | |
742 | device_init_wakeup(&client->dev, false); | |
50c3304a | 743 | return status; |
f37dd80a | 744 | } |
1da177e4 | 745 | |
f37dd80a DB |
746 | static int i2c_device_remove(struct device *dev) |
747 | { | |
51298d12 | 748 | struct i2c_client *client = i2c_verify_client(dev); |
a1d9e6e4 | 749 | struct i2c_driver *driver; |
72fa818e | 750 | int status = 0; |
a1d9e6e4 | 751 | |
51298d12 | 752 | if (!client || !dev->driver) |
a1d9e6e4 DB |
753 | return 0; |
754 | ||
755 | driver = to_i2c_driver(dev->driver); | |
756 | if (driver->remove) { | |
757 | dev_dbg(dev, "remove\n"); | |
758 | status = driver->remove(client); | |
a1d9e6e4 | 759 | } |
72fa818e | 760 | |
e09b0d4e | 761 | dev_pm_domain_detach(&client->dev, true); |
3fffd128 DT |
762 | |
763 | dev_pm_clear_wake_irq(&client->dev); | |
764 | device_init_wakeup(&client->dev, false); | |
765 | ||
a1d9e6e4 | 766 | return status; |
1da177e4 LT |
767 | } |
768 | ||
f37dd80a | 769 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 770 | { |
51298d12 | 771 | struct i2c_client *client = i2c_verify_client(dev); |
f37dd80a DB |
772 | struct i2c_driver *driver; |
773 | ||
51298d12 | 774 | if (!client || !dev->driver) |
f37dd80a DB |
775 | return; |
776 | driver = to_i2c_driver(dev->driver); | |
777 | if (driver->shutdown) | |
51298d12 | 778 | driver->shutdown(client); |
1da177e4 LT |
779 | } |
780 | ||
9c1600ed DB |
781 | static void i2c_client_dev_release(struct device *dev) |
782 | { | |
783 | kfree(to_i2c_client(dev)); | |
784 | } | |
785 | ||
09b8ce0a | 786 | static ssize_t |
4f8cf824 | 787 | show_name(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 | 788 | { |
4f8cf824 JD |
789 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
790 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); | |
7b4fbc50 | 791 | } |
a5eb71b2 | 792 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); |
7b4fbc50 | 793 | |
09b8ce0a ZX |
794 | static ssize_t |
795 | show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
7b4fbc50 DB |
796 | { |
797 | struct i2c_client *client = to_i2c_client(dev); | |
8c4ff6d0 ZR |
798 | int len; |
799 | ||
800 | len = acpi_device_modalias(dev, buf, PAGE_SIZE -1); | |
801 | if (len != -ENODEV) | |
802 | return len; | |
803 | ||
eb8a7908 | 804 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 | 805 | } |
51298d12 JD |
806 | static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); |
807 | ||
808 | static struct attribute *i2c_dev_attrs[] = { | |
809 | &dev_attr_name.attr, | |
7b4fbc50 | 810 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
51298d12 JD |
811 | &dev_attr_modalias.attr, |
812 | NULL | |
813 | }; | |
a5eb71b2 | 814 | ATTRIBUTE_GROUPS(i2c_dev); |
54067ee2 | 815 | |
e9ca9eb9 | 816 | struct bus_type i2c_bus_type = { |
f37dd80a DB |
817 | .name = "i2c", |
818 | .match = i2c_device_match, | |
819 | .probe = i2c_device_probe, | |
820 | .remove = i2c_device_remove, | |
821 | .shutdown = i2c_device_shutdown, | |
b864c7d5 | 822 | }; |
e9ca9eb9 | 823 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
b864c7d5 | 824 | |
51298d12 | 825 | static struct device_type i2c_client_type = { |
a5eb71b2 | 826 | .groups = i2c_dev_groups, |
51298d12 JD |
827 | .uevent = i2c_device_uevent, |
828 | .release = i2c_client_dev_release, | |
829 | }; | |
830 | ||
9b766b81 DB |
831 | |
832 | /** | |
833 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
834 | * @dev: device, probably from some driver model iterator | |
835 | * | |
836 | * When traversing the driver model tree, perhaps using driver model | |
837 | * iterators like @device_for_each_child(), you can't assume very much | |
838 | * about the nodes you find. Use this function to avoid oopses caused | |
839 | * by wrongly treating some non-I2C device as an i2c_client. | |
840 | */ | |
841 | struct i2c_client *i2c_verify_client(struct device *dev) | |
842 | { | |
51298d12 | 843 | return (dev->type == &i2c_client_type) |
9b766b81 DB |
844 | ? to_i2c_client(dev) |
845 | : NULL; | |
846 | } | |
847 | EXPORT_SYMBOL(i2c_verify_client); | |
848 | ||
849 | ||
da899f55 WS |
850 | /* Return a unique address which takes the flags of the client into account */ |
851 | static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client) | |
852 | { | |
853 | unsigned short addr = client->addr; | |
854 | ||
855 | /* For some client flags, add an arbitrary offset to avoid collisions */ | |
856 | if (client->flags & I2C_CLIENT_TEN) | |
857 | addr |= I2C_ADDR_OFFSET_TEN_BIT; | |
858 | ||
859 | if (client->flags & I2C_CLIENT_SLAVE) | |
860 | addr |= I2C_ADDR_OFFSET_SLAVE; | |
861 | ||
862 | return addr; | |
863 | } | |
864 | ||
3a89db5f | 865 | /* This is a permissive address validity check, I2C address map constraints |
25985edc | 866 | * are purposely not enforced, except for the general call address. */ |
c4019b70 | 867 | static int i2c_check_addr_validity(unsigned addr, unsigned short flags) |
3a89db5f | 868 | { |
c4019b70 | 869 | if (flags & I2C_CLIENT_TEN) { |
3a89db5f | 870 | /* 10-bit address, all values are valid */ |
c4019b70 | 871 | if (addr > 0x3ff) |
3a89db5f JD |
872 | return -EINVAL; |
873 | } else { | |
874 | /* 7-bit address, reject the general call address */ | |
c4019b70 | 875 | if (addr == 0x00 || addr > 0x7f) |
3a89db5f JD |
876 | return -EINVAL; |
877 | } | |
878 | return 0; | |
879 | } | |
880 | ||
656b8761 JD |
881 | /* And this is a strict address validity check, used when probing. If a |
882 | * device uses a reserved address, then it shouldn't be probed. 7-bit | |
883 | * addressing is assumed, 10-bit address devices are rare and should be | |
884 | * explicitly enumerated. */ | |
66be6056 | 885 | static int i2c_check_7bit_addr_validity_strict(unsigned short addr) |
656b8761 JD |
886 | { |
887 | /* | |
888 | * Reserved addresses per I2C specification: | |
889 | * 0x00 General call address / START byte | |
890 | * 0x01 CBUS address | |
891 | * 0x02 Reserved for different bus format | |
892 | * 0x03 Reserved for future purposes | |
893 | * 0x04-0x07 Hs-mode master code | |
894 | * 0x78-0x7b 10-bit slave addressing | |
895 | * 0x7c-0x7f Reserved for future purposes | |
896 | */ | |
897 | if (addr < 0x08 || addr > 0x77) | |
898 | return -EINVAL; | |
899 | return 0; | |
900 | } | |
901 | ||
3b5f794b JD |
902 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
903 | { | |
904 | struct i2c_client *client = i2c_verify_client(dev); | |
905 | int addr = *(int *)addrp; | |
906 | ||
9bccc70a | 907 | if (client && i2c_encode_flags_to_addr(client) == addr) |
3b5f794b JD |
908 | return -EBUSY; |
909 | return 0; | |
910 | } | |
911 | ||
0826374b ML |
912 | /* walk up mux tree */ |
913 | static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) | |
914 | { | |
97cc4d49 | 915 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
916 | int result; |
917 | ||
918 | result = device_for_each_child(&adapter->dev, &addr, | |
919 | __i2c_check_addr_busy); | |
920 | ||
97cc4d49 JD |
921 | if (!result && parent) |
922 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
923 | |
924 | return result; | |
925 | } | |
926 | ||
927 | /* recurse down mux tree */ | |
928 | static int i2c_check_mux_children(struct device *dev, void *addrp) | |
929 | { | |
930 | int result; | |
931 | ||
932 | if (dev->type == &i2c_adapter_type) | |
933 | result = device_for_each_child(dev, addrp, | |
934 | i2c_check_mux_children); | |
935 | else | |
936 | result = __i2c_check_addr_busy(dev, addrp); | |
937 | ||
938 | return result; | |
939 | } | |
940 | ||
3b5f794b JD |
941 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) |
942 | { | |
97cc4d49 | 943 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
944 | int result = 0; |
945 | ||
97cc4d49 JD |
946 | if (parent) |
947 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
948 | |
949 | if (!result) | |
950 | result = device_for_each_child(&adapter->dev, &addr, | |
951 | i2c_check_mux_children); | |
952 | ||
953 | return result; | |
3b5f794b JD |
954 | } |
955 | ||
fe61e07e | 956 | /** |
8320f495 | 957 | * i2c_adapter_lock_bus - Get exclusive access to an I2C bus segment |
fe61e07e | 958 | * @adapter: Target I2C bus segment |
8320f495 PR |
959 | * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT |
960 | * locks only this branch in the adapter tree | |
fe61e07e | 961 | */ |
8320f495 PR |
962 | static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, |
963 | unsigned int flags) | |
fe61e07e | 964 | { |
fa96f0cb | 965 | rt_mutex_lock(&adapter->bus_lock); |
fe61e07e | 966 | } |
fe61e07e JD |
967 | |
968 | /** | |
8320f495 | 969 | * i2c_adapter_trylock_bus - Try to get exclusive access to an I2C bus segment |
fe61e07e | 970 | * @adapter: Target I2C bus segment |
8320f495 PR |
971 | * @flags: I2C_LOCK_ROOT_ADAPTER trylocks the root i2c adapter, I2C_LOCK_SEGMENT |
972 | * trylocks only this branch in the adapter tree | |
fe61e07e | 973 | */ |
8320f495 PR |
974 | static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, |
975 | unsigned int flags) | |
fe61e07e | 976 | { |
fa96f0cb | 977 | return rt_mutex_trylock(&adapter->bus_lock); |
fe61e07e JD |
978 | } |
979 | ||
980 | /** | |
8320f495 | 981 | * i2c_adapter_unlock_bus - Release exclusive access to an I2C bus segment |
fe61e07e | 982 | * @adapter: Target I2C bus segment |
8320f495 PR |
983 | * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT |
984 | * unlocks only this branch in the adapter tree | |
fe61e07e | 985 | */ |
8320f495 PR |
986 | static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter, |
987 | unsigned int flags) | |
fe61e07e | 988 | { |
fa96f0cb | 989 | rt_mutex_unlock(&adapter->bus_lock); |
fe61e07e | 990 | } |
fe61e07e | 991 | |
70762abb JN |
992 | static void i2c_dev_set_name(struct i2c_adapter *adap, |
993 | struct i2c_client *client) | |
994 | { | |
995 | struct acpi_device *adev = ACPI_COMPANION(&client->dev); | |
996 | ||
997 | if (adev) { | |
998 | dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); | |
999 | return; | |
1000 | } | |
1001 | ||
70762abb | 1002 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), |
da899f55 | 1003 | i2c_encode_flags_to_addr(client)); |
70762abb JN |
1004 | } |
1005 | ||
9c1600ed | 1006 | /** |
f8a227e8 | 1007 | * i2c_new_device - instantiate an i2c device |
9c1600ed DB |
1008 | * @adap: the adapter managing the device |
1009 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 1010 | * Context: can sleep |
9c1600ed | 1011 | * |
f8a227e8 JD |
1012 | * Create an i2c device. Binding is handled through driver model |
1013 | * probe()/remove() methods. A driver may be bound to this device when we | |
1014 | * return from this function, or any later moment (e.g. maybe hotplugging will | |
1015 | * load the driver module). This call is not appropriate for use by mainboard | |
1016 | * initialization logic, which usually runs during an arch_initcall() long | |
1017 | * before any i2c_adapter could exist. | |
9c1600ed DB |
1018 | * |
1019 | * This returns the new i2c client, which may be saved for later use with | |
1020 | * i2c_unregister_device(); or NULL to indicate an error. | |
1021 | */ | |
1022 | struct i2c_client * | |
1023 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
1024 | { | |
1025 | struct i2c_client *client; | |
1026 | int status; | |
1027 | ||
1028 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
1029 | if (!client) | |
1030 | return NULL; | |
1031 | ||
1032 | client->adapter = adap; | |
1033 | ||
1034 | client->dev.platform_data = info->platform_data; | |
3bbb835d | 1035 | |
11f1f2af AV |
1036 | if (info->archdata) |
1037 | client->dev.archdata = *info->archdata; | |
1038 | ||
ee35425c | 1039 | client->flags = info->flags; |
9c1600ed DB |
1040 | client->addr = info->addr; |
1041 | client->irq = info->irq; | |
1042 | ||
9c1600ed DB |
1043 | strlcpy(client->name, info->type, sizeof(client->name)); |
1044 | ||
c4019b70 | 1045 | status = i2c_check_addr_validity(client->addr, client->flags); |
3a89db5f JD |
1046 | if (status) { |
1047 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", | |
1048 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); | |
1049 | goto out_err_silent; | |
1050 | } | |
1051 | ||
f8a227e8 | 1052 | /* Check for address business */ |
9bccc70a | 1053 | status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client)); |
f8a227e8 JD |
1054 | if (status) |
1055 | goto out_err; | |
1056 | ||
1057 | client->dev.parent = &client->adapter->dev; | |
1058 | client->dev.bus = &i2c_bus_type; | |
51298d12 | 1059 | client->dev.type = &i2c_client_type; |
d12d42f7 | 1060 | client->dev.of_node = info->of_node; |
ce793486 | 1061 | client->dev.fwnode = info->fwnode; |
f8a227e8 | 1062 | |
70762abb | 1063 | i2c_dev_set_name(adap, client); |
f8a227e8 JD |
1064 | status = device_register(&client->dev); |
1065 | if (status) | |
1066 | goto out_err; | |
1067 | ||
f8a227e8 JD |
1068 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
1069 | client->name, dev_name(&client->dev)); | |
1070 | ||
9c1600ed | 1071 | return client; |
f8a227e8 JD |
1072 | |
1073 | out_err: | |
1074 | dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x " | |
1075 | "(%d)\n", client->name, client->addr, status); | |
3a89db5f | 1076 | out_err_silent: |
f8a227e8 JD |
1077 | kfree(client); |
1078 | return NULL; | |
9c1600ed DB |
1079 | } |
1080 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
1081 | ||
1082 | ||
1083 | /** | |
1084 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
1085 | * @client: value returned from i2c_new_device() | |
d64f73be | 1086 | * Context: can sleep |
9c1600ed DB |
1087 | */ |
1088 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 | 1089 | { |
4f001fd3 PA |
1090 | if (client->dev.of_node) |
1091 | of_node_clear_flag(client->dev.of_node, OF_POPULATED); | |
a1d9e6e4 DB |
1092 | device_unregister(&client->dev); |
1093 | } | |
9c1600ed | 1094 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
1095 | |
1096 | ||
60b129d7 JD |
1097 | static const struct i2c_device_id dummy_id[] = { |
1098 | { "dummy", 0 }, | |
1099 | { }, | |
1100 | }; | |
1101 | ||
d2653e92 JD |
1102 | static int dummy_probe(struct i2c_client *client, |
1103 | const struct i2c_device_id *id) | |
1104 | { | |
1105 | return 0; | |
1106 | } | |
1107 | ||
1108 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
1109 | { |
1110 | return 0; | |
1111 | } | |
1112 | ||
1113 | static struct i2c_driver dummy_driver = { | |
1114 | .driver.name = "dummy", | |
d2653e92 JD |
1115 | .probe = dummy_probe, |
1116 | .remove = dummy_remove, | |
60b129d7 | 1117 | .id_table = dummy_id, |
e9f1373b DB |
1118 | }; |
1119 | ||
1120 | /** | |
1121 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
1122 | * @adapter: the adapter managing the device | |
1123 | * @address: seven bit address to be used | |
e9f1373b DB |
1124 | * Context: can sleep |
1125 | * | |
1126 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
1127 | * with devices that consume multiple addresses. Examples of such chips | |
1128 | * include various EEPROMS (like 24c04 and 24c08 models). | |
1129 | * | |
1130 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
1131 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
1132 | * And second, this prevents the specified address from being bound to a | |
1133 | * different driver. | |
1134 | * | |
1135 | * This returns the new i2c client, which should be saved for later use with | |
1136 | * i2c_unregister_device(); or NULL to indicate an error. | |
1137 | */ | |
09b8ce0a | 1138 | struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
1139 | { |
1140 | struct i2c_board_info info = { | |
60b129d7 | 1141 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
1142 | }; |
1143 | ||
e9f1373b DB |
1144 | return i2c_new_device(adapter, &info); |
1145 | } | |
1146 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
1147 | ||
0f614d83 JMH |
1148 | /** |
1149 | * i2c_new_secondary_device - Helper to get the instantiated secondary address | |
1150 | * and create the associated device | |
1151 | * @client: Handle to the primary client | |
1152 | * @name: Handle to specify which secondary address to get | |
1153 | * @default_addr: Used as a fallback if no secondary address was specified | |
1154 | * Context: can sleep | |
1155 | * | |
1156 | * I2C clients can be composed of multiple I2C slaves bound together in a single | |
1157 | * component. The I2C client driver then binds to the master I2C slave and needs | |
1158 | * to create I2C dummy clients to communicate with all the other slaves. | |
1159 | * | |
1160 | * This function creates and returns an I2C dummy client whose I2C address is | |
1161 | * retrieved from the platform firmware based on the given slave name. If no | |
1162 | * address is specified by the firmware default_addr is used. | |
1163 | * | |
1164 | * On DT-based platforms the address is retrieved from the "reg" property entry | |
1165 | * cell whose "reg-names" value matches the slave name. | |
1166 | * | |
1167 | * This returns the new i2c client, which should be saved for later use with | |
1168 | * i2c_unregister_device(); or NULL to indicate an error. | |
1169 | */ | |
1170 | struct i2c_client *i2c_new_secondary_device(struct i2c_client *client, | |
1171 | const char *name, | |
1172 | u16 default_addr) | |
1173 | { | |
1174 | struct device_node *np = client->dev.of_node; | |
1175 | u32 addr = default_addr; | |
1176 | int i; | |
1177 | ||
1178 | if (np) { | |
1179 | i = of_property_match_string(np, "reg-names", name); | |
1180 | if (i >= 0) | |
1181 | of_property_read_u32_index(np, "reg", i, &addr); | |
1182 | } | |
1183 | ||
1184 | dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr); | |
1185 | return i2c_new_dummy(client->adapter, addr); | |
1186 | } | |
1187 | EXPORT_SYMBOL_GPL(i2c_new_secondary_device); | |
1188 | ||
f37dd80a DB |
1189 | /* ------------------------------------------------------------------------- */ |
1190 | ||
16ffadfc DB |
1191 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
1192 | ||
83eaaed0 | 1193 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 1194 | { |
ef2c8321 | 1195 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
1196 | complete(&adap->dev_released); |
1197 | } | |
1198 | ||
390946b1 JD |
1199 | /* |
1200 | * This function is only needed for mutex_lock_nested, so it is never | |
1201 | * called unless locking correctness checking is enabled. Thus we | |
1202 | * make it inline to avoid a compiler warning. That's what gcc ends up | |
1203 | * doing anyway. | |
1204 | */ | |
1205 | static inline unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) | |
1206 | { | |
1207 | unsigned int depth = 0; | |
1208 | ||
1209 | while ((adapter = i2c_parent_is_i2c_adapter(adapter))) | |
1210 | depth++; | |
1211 | ||
1212 | return depth; | |
1213 | } | |
1214 | ||
99cd8e25 JD |
1215 | /* |
1216 | * Let users instantiate I2C devices through sysfs. This can be used when | |
1217 | * platform initialization code doesn't contain the proper data for | |
1218 | * whatever reason. Also useful for drivers that do device detection and | |
1219 | * detection fails, either because the device uses an unexpected address, | |
1220 | * or this is a compatible device with different ID register values. | |
1221 | * | |
1222 | * Parameter checking may look overzealous, but we really don't want | |
1223 | * the user to provide incorrect parameters. | |
1224 | */ | |
1225 | static ssize_t | |
1226 | i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, | |
1227 | const char *buf, size_t count) | |
1228 | { | |
1229 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
1230 | struct i2c_board_info info; | |
1231 | struct i2c_client *client; | |
1232 | char *blank, end; | |
1233 | int res; | |
1234 | ||
99cd8e25 JD |
1235 | memset(&info, 0, sizeof(struct i2c_board_info)); |
1236 | ||
1237 | blank = strchr(buf, ' '); | |
1238 | if (!blank) { | |
1239 | dev_err(dev, "%s: Missing parameters\n", "new_device"); | |
1240 | return -EINVAL; | |
1241 | } | |
1242 | if (blank - buf > I2C_NAME_SIZE - 1) { | |
1243 | dev_err(dev, "%s: Invalid device name\n", "new_device"); | |
1244 | return -EINVAL; | |
1245 | } | |
1246 | memcpy(info.type, buf, blank - buf); | |
1247 | ||
1248 | /* Parse remaining parameters, reject extra parameters */ | |
1249 | res = sscanf(++blank, "%hi%c", &info.addr, &end); | |
1250 | if (res < 1) { | |
1251 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); | |
1252 | return -EINVAL; | |
1253 | } | |
1254 | if (res > 1 && end != '\n') { | |
1255 | dev_err(dev, "%s: Extra parameters\n", "new_device"); | |
1256 | return -EINVAL; | |
1257 | } | |
1258 | ||
cfa0327b WS |
1259 | if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) { |
1260 | info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT; | |
1261 | info.flags |= I2C_CLIENT_TEN; | |
1262 | } | |
1263 | ||
1264 | if (info.addr & I2C_ADDR_OFFSET_SLAVE) { | |
1265 | info.addr &= ~I2C_ADDR_OFFSET_SLAVE; | |
1266 | info.flags |= I2C_CLIENT_SLAVE; | |
1267 | } | |
1268 | ||
99cd8e25 JD |
1269 | client = i2c_new_device(adap, &info); |
1270 | if (!client) | |
3a89db5f | 1271 | return -EINVAL; |
99cd8e25 JD |
1272 | |
1273 | /* Keep track of the added device */ | |
dafc50d1 | 1274 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff | 1275 | list_add_tail(&client->detected, &adap->userspace_clients); |
dafc50d1 | 1276 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
1277 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
1278 | info.type, info.addr); | |
1279 | ||
1280 | return count; | |
1281 | } | |
a5eb71b2 | 1282 | static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); |
99cd8e25 JD |
1283 | |
1284 | /* | |
1285 | * And of course let the users delete the devices they instantiated, if | |
1286 | * they got it wrong. This interface can only be used to delete devices | |
1287 | * instantiated by i2c_sysfs_new_device above. This guarantees that we | |
1288 | * don't delete devices to which some kernel code still has references. | |
1289 | * | |
1290 | * Parameter checking may look overzealous, but we really don't want | |
1291 | * the user to delete the wrong device. | |
1292 | */ | |
1293 | static ssize_t | |
1294 | i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, | |
1295 | const char *buf, size_t count) | |
1296 | { | |
1297 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
1298 | struct i2c_client *client, *next; | |
1299 | unsigned short addr; | |
1300 | char end; | |
1301 | int res; | |
1302 | ||
1303 | /* Parse parameters, reject extra parameters */ | |
1304 | res = sscanf(buf, "%hi%c", &addr, &end); | |
1305 | if (res < 1) { | |
1306 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); | |
1307 | return -EINVAL; | |
1308 | } | |
1309 | if (res > 1 && end != '\n') { | |
1310 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); | |
1311 | return -EINVAL; | |
1312 | } | |
1313 | ||
1314 | /* Make sure the device was added through sysfs */ | |
1315 | res = -ENOENT; | |
390946b1 JD |
1316 | mutex_lock_nested(&adap->userspace_clients_lock, |
1317 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1318 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1319 | detected) { | |
cfa0327b | 1320 | if (i2c_encode_flags_to_addr(client) == addr) { |
99cd8e25 JD |
1321 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
1322 | "delete_device", client->name, client->addr); | |
1323 | ||
1324 | list_del(&client->detected); | |
1325 | i2c_unregister_device(client); | |
1326 | res = count; | |
1327 | break; | |
1328 | } | |
1329 | } | |
dafc50d1 | 1330 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
1331 | |
1332 | if (res < 0) | |
1333 | dev_err(dev, "%s: Can't find device in list\n", | |
1334 | "delete_device"); | |
1335 | return res; | |
1336 | } | |
e9b526fe AS |
1337 | static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, |
1338 | i2c_sysfs_delete_device); | |
4f8cf824 JD |
1339 | |
1340 | static struct attribute *i2c_adapter_attrs[] = { | |
1341 | &dev_attr_name.attr, | |
1342 | &dev_attr_new_device.attr, | |
1343 | &dev_attr_delete_device.attr, | |
1344 | NULL | |
1345 | }; | |
a5eb71b2 | 1346 | ATTRIBUTE_GROUPS(i2c_adapter); |
b119dc3f | 1347 | |
0826374b | 1348 | struct device_type i2c_adapter_type = { |
a5eb71b2 | 1349 | .groups = i2c_adapter_groups, |
4f8cf824 | 1350 | .release = i2c_adapter_dev_release, |
1da177e4 | 1351 | }; |
0826374b | 1352 | EXPORT_SYMBOL_GPL(i2c_adapter_type); |
1da177e4 | 1353 | |
643dd09e SW |
1354 | /** |
1355 | * i2c_verify_adapter - return parameter as i2c_adapter or NULL | |
1356 | * @dev: device, probably from some driver model iterator | |
1357 | * | |
1358 | * When traversing the driver model tree, perhaps using driver model | |
1359 | * iterators like @device_for_each_child(), you can't assume very much | |
1360 | * about the nodes you find. Use this function to avoid oopses caused | |
1361 | * by wrongly treating some non-I2C device as an i2c_adapter. | |
1362 | */ | |
1363 | struct i2c_adapter *i2c_verify_adapter(struct device *dev) | |
1364 | { | |
1365 | return (dev->type == &i2c_adapter_type) | |
1366 | ? to_i2c_adapter(dev) | |
1367 | : NULL; | |
1368 | } | |
1369 | EXPORT_SYMBOL(i2c_verify_adapter); | |
1370 | ||
2bb5095a JD |
1371 | #ifdef CONFIG_I2C_COMPAT |
1372 | static struct class_compat *i2c_adapter_compat_class; | |
1373 | #endif | |
1374 | ||
9c1600ed DB |
1375 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
1376 | { | |
1377 | struct i2c_devinfo *devinfo; | |
1378 | ||
f18c41da | 1379 | down_read(&__i2c_board_lock); |
9c1600ed DB |
1380 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
1381 | if (devinfo->busnum == adapter->nr | |
1382 | && !i2c_new_device(adapter, | |
1383 | &devinfo->board_info)) | |
09b8ce0a ZX |
1384 | dev_err(&adapter->dev, |
1385 | "Can't create device at 0x%02x\n", | |
9c1600ed DB |
1386 | devinfo->board_info.addr); |
1387 | } | |
f18c41da | 1388 | up_read(&__i2c_board_lock); |
9c1600ed DB |
1389 | } |
1390 | ||
687b81d0 WS |
1391 | /* OF support code */ |
1392 | ||
1393 | #if IS_ENABLED(CONFIG_OF) | |
a430a345 PA |
1394 | static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap, |
1395 | struct device_node *node) | |
687b81d0 | 1396 | { |
a430a345 PA |
1397 | struct i2c_client *result; |
1398 | struct i2c_board_info info = {}; | |
1399 | struct dev_archdata dev_ad = {}; | |
b4e2f6ac WS |
1400 | const __be32 *addr_be; |
1401 | u32 addr; | |
a430a345 | 1402 | int len; |
687b81d0 | 1403 | |
a430a345 | 1404 | dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name); |
687b81d0 | 1405 | |
a430a345 PA |
1406 | if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) { |
1407 | dev_err(&adap->dev, "of_i2c: modalias failure on %s\n", | |
1408 | node->full_name); | |
1409 | return ERR_PTR(-EINVAL); | |
1410 | } | |
687b81d0 | 1411 | |
b4e2f6ac WS |
1412 | addr_be = of_get_property(node, "reg", &len); |
1413 | if (!addr_be || (len < sizeof(*addr_be))) { | |
a430a345 PA |
1414 | dev_err(&adap->dev, "of_i2c: invalid reg on %s\n", |
1415 | node->full_name); | |
1416 | return ERR_PTR(-EINVAL); | |
1417 | } | |
687b81d0 | 1418 | |
b4e2f6ac WS |
1419 | addr = be32_to_cpup(addr_be); |
1420 | if (addr & I2C_TEN_BIT_ADDRESS) { | |
1421 | addr &= ~I2C_TEN_BIT_ADDRESS; | |
1422 | info.flags |= I2C_CLIENT_TEN; | |
1423 | } | |
1424 | ||
1425 | if (addr & I2C_OWN_SLAVE_ADDRESS) { | |
1426 | addr &= ~I2C_OWN_SLAVE_ADDRESS; | |
1427 | info.flags |= I2C_CLIENT_SLAVE; | |
1428 | } | |
1429 | ||
1430 | if (i2c_check_addr_validity(addr, info.flags)) { | |
a430a345 PA |
1431 | dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n", |
1432 | info.addr, node->full_name); | |
1433 | return ERR_PTR(-EINVAL); | |
1434 | } | |
687b81d0 | 1435 | |
b4e2f6ac | 1436 | info.addr = addr; |
a430a345 PA |
1437 | info.of_node = of_node_get(node); |
1438 | info.archdata = &dev_ad; | |
687b81d0 | 1439 | |
a430a345 PA |
1440 | if (of_get_property(node, "wakeup-source", NULL)) |
1441 | info.flags |= I2C_CLIENT_WAKE; | |
687b81d0 | 1442 | |
a430a345 PA |
1443 | result = i2c_new_device(adap, &info); |
1444 | if (result == NULL) { | |
1445 | dev_err(&adap->dev, "of_i2c: Failure registering %s\n", | |
1446 | node->full_name); | |
1447 | of_node_put(node); | |
a430a345 PA |
1448 | return ERR_PTR(-EINVAL); |
1449 | } | |
1450 | return result; | |
1451 | } | |
687b81d0 | 1452 | |
a430a345 PA |
1453 | static void of_i2c_register_devices(struct i2c_adapter *adap) |
1454 | { | |
1455 | struct device_node *node; | |
687b81d0 | 1456 | |
a430a345 PA |
1457 | /* Only register child devices if the adapter has a node pointer set */ |
1458 | if (!adap->dev.of_node) | |
1459 | return; | |
687b81d0 | 1460 | |
a430a345 PA |
1461 | dev_dbg(&adap->dev, "of_i2c: walking child nodes\n"); |
1462 | ||
4f001fd3 PA |
1463 | for_each_available_child_of_node(adap->dev.of_node, node) { |
1464 | if (of_node_test_and_set_flag(node, OF_POPULATED)) | |
1465 | continue; | |
a430a345 | 1466 | of_i2c_register_device(adap, node); |
4f001fd3 | 1467 | } |
687b81d0 WS |
1468 | } |
1469 | ||
1470 | static int of_dev_node_match(struct device *dev, void *data) | |
1471 | { | |
1472 | return dev->of_node == data; | |
1473 | } | |
1474 | ||
1475 | /* must call put_device() when done with returned i2c_client device */ | |
1476 | struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) | |
1477 | { | |
1478 | struct device *dev; | |
e3311469 | 1479 | struct i2c_client *client; |
687b81d0 | 1480 | |
e3311469 | 1481 | dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match); |
687b81d0 WS |
1482 | if (!dev) |
1483 | return NULL; | |
1484 | ||
e3311469 VZ |
1485 | client = i2c_verify_client(dev); |
1486 | if (!client) | |
1487 | put_device(dev); | |
1488 | ||
1489 | return client; | |
687b81d0 WS |
1490 | } |
1491 | EXPORT_SYMBOL(of_find_i2c_device_by_node); | |
1492 | ||
1493 | /* must call put_device() when done with returned i2c_adapter device */ | |
1494 | struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) | |
1495 | { | |
1496 | struct device *dev; | |
e3311469 | 1497 | struct i2c_adapter *adapter; |
687b81d0 | 1498 | |
e3311469 | 1499 | dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match); |
687b81d0 WS |
1500 | if (!dev) |
1501 | return NULL; | |
1502 | ||
e3311469 VZ |
1503 | adapter = i2c_verify_adapter(dev); |
1504 | if (!adapter) | |
1505 | put_device(dev); | |
1506 | ||
1507 | return adapter; | |
687b81d0 WS |
1508 | } |
1509 | EXPORT_SYMBOL(of_find_i2c_adapter_by_node); | |
48e9743d VZ |
1510 | |
1511 | /* must call i2c_put_adapter() when done with returned i2c_adapter device */ | |
1512 | struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) | |
1513 | { | |
1514 | struct i2c_adapter *adapter; | |
1515 | ||
1516 | adapter = of_find_i2c_adapter_by_node(node); | |
1517 | if (!adapter) | |
1518 | return NULL; | |
1519 | ||
1520 | if (!try_module_get(adapter->owner)) { | |
1521 | put_device(&adapter->dev); | |
1522 | adapter = NULL; | |
1523 | } | |
1524 | ||
1525 | return adapter; | |
1526 | } | |
1527 | EXPORT_SYMBOL(of_get_i2c_adapter_by_node); | |
687b81d0 WS |
1528 | #else |
1529 | static void of_i2c_register_devices(struct i2c_adapter *adap) { } | |
1530 | #endif /* CONFIG_OF */ | |
1531 | ||
69b0089a JD |
1532 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
1533 | struct i2c_adapter *adap) | |
026526f5 | 1534 | { |
4735c98f JD |
1535 | /* Detect supported devices on that bus, and instantiate them */ |
1536 | i2c_detect(adap, driver); | |
1537 | ||
1538 | /* Let legacy drivers scan this bus for matching devices */ | |
026526f5 | 1539 | if (driver->attach_adapter) { |
a920ff41 JD |
1540 | dev_warn(&adap->dev, "%s: attach_adapter method is deprecated\n", |
1541 | driver->driver.name); | |
fe6fc258 JD |
1542 | dev_warn(&adap->dev, "Please use another way to instantiate " |
1543 | "your i2c_client\n"); | |
026526f5 JD |
1544 | /* We ignore the return code; if it fails, too bad */ |
1545 | driver->attach_adapter(adap); | |
1546 | } | |
1547 | return 0; | |
1548 | } | |
1549 | ||
69b0089a JD |
1550 | static int __process_new_adapter(struct device_driver *d, void *data) |
1551 | { | |
1552 | return i2c_do_add_adapter(to_i2c_driver(d), data); | |
1553 | } | |
1554 | ||
6e13e641 | 1555 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 1556 | { |
ce0dffaf | 1557 | int res = -EINVAL; |
1da177e4 | 1558 | |
1d0b19c9 | 1559 | /* Can't register until after driver model init */ |
95026658 | 1560 | if (WARN_ON(!is_registered)) { |
35fc37f8 JD |
1561 | res = -EAGAIN; |
1562 | goto out_list; | |
1563 | } | |
1d0b19c9 | 1564 | |
2236baa7 JD |
1565 | /* Sanity checks */ |
1566 | if (unlikely(adap->name[0] == '\0')) { | |
1567 | pr_err("i2c-core: Attempt to register an adapter with " | |
1568 | "no name!\n"); | |
ce0dffaf | 1569 | goto out_list; |
2236baa7 JD |
1570 | } |
1571 | if (unlikely(!adap->algo)) { | |
1572 | pr_err("i2c-core: Attempt to register adapter '%s' with " | |
1573 | "no algo!\n", adap->name); | |
ce0dffaf | 1574 | goto out_list; |
2236baa7 JD |
1575 | } |
1576 | ||
8320f495 PR |
1577 | if (!adap->lock_bus) { |
1578 | adap->lock_bus = i2c_adapter_lock_bus; | |
1579 | adap->trylock_bus = i2c_adapter_trylock_bus; | |
1580 | adap->unlock_bus = i2c_adapter_unlock_bus; | |
1581 | } | |
1582 | ||
194684e5 | 1583 | rt_mutex_init(&adap->bus_lock); |
6ef91fcc | 1584 | rt_mutex_init(&adap->mux_lock); |
dafc50d1 | 1585 | mutex_init(&adap->userspace_clients_lock); |
6629dcff | 1586 | INIT_LIST_HEAD(&adap->userspace_clients); |
1da177e4 | 1587 | |
8fcfef6e JD |
1588 | /* Set default timeout to 1 second if not already set */ |
1589 | if (adap->timeout == 0) | |
1590 | adap->timeout = HZ; | |
1591 | ||
27d9c183 | 1592 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
4f8cf824 JD |
1593 | adap->dev.bus = &i2c_bus_type; |
1594 | adap->dev.type = &i2c_adapter_type; | |
b119c6c9 JD |
1595 | res = device_register(&adap->dev); |
1596 | if (res) | |
1597 | goto out_list; | |
1da177e4 | 1598 | |
b6d7b3d1 JD |
1599 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
1600 | ||
6ada5c1e | 1601 | pm_runtime_no_callbacks(&adap->dev); |
04f59143 | 1602 | pm_suspend_ignore_children(&adap->dev, true); |
9f924169 | 1603 | pm_runtime_enable(&adap->dev); |
6ada5c1e | 1604 | |
2bb5095a JD |
1605 | #ifdef CONFIG_I2C_COMPAT |
1606 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, | |
1607 | adap->dev.parent); | |
1608 | if (res) | |
1609 | dev_warn(&adap->dev, | |
1610 | "Failed to create compatibility class link\n"); | |
1611 | #endif | |
1612 | ||
5f9296ba VK |
1613 | /* bus recovery specific initialization */ |
1614 | if (adap->bus_recovery_info) { | |
1615 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
1616 | ||
1617 | if (!bri->recover_bus) { | |
1618 | dev_err(&adap->dev, "No recover_bus() found, not using recovery\n"); | |
1619 | adap->bus_recovery_info = NULL; | |
1620 | goto exit_recovery; | |
1621 | } | |
1622 | ||
1623 | /* Generic GPIO recovery */ | |
1624 | if (bri->recover_bus == i2c_generic_gpio_recovery) { | |
1625 | if (!gpio_is_valid(bri->scl_gpio)) { | |
1626 | dev_err(&adap->dev, "Invalid SCL gpio, not using recovery\n"); | |
1627 | adap->bus_recovery_info = NULL; | |
1628 | goto exit_recovery; | |
1629 | } | |
1630 | ||
1631 | if (gpio_is_valid(bri->sda_gpio)) | |
1632 | bri->get_sda = get_sda_gpio_value; | |
1633 | else | |
1634 | bri->get_sda = NULL; | |
1635 | ||
1636 | bri->get_scl = get_scl_gpio_value; | |
1637 | bri->set_scl = set_scl_gpio_value; | |
3a9ddaf4 | 1638 | } else if (bri->recover_bus == i2c_generic_scl_recovery) { |
5f9296ba | 1639 | /* Generic SCL recovery */ |
3a9ddaf4 WS |
1640 | if (!bri->set_scl || !bri->get_scl) { |
1641 | dev_err(&adap->dev, "No {get|set}_scl() found, not using recovery\n"); | |
1642 | adap->bus_recovery_info = NULL; | |
1643 | } | |
5f9296ba VK |
1644 | } |
1645 | } | |
1646 | ||
1647 | exit_recovery: | |
729d6dd5 | 1648 | /* create pre-declared device nodes */ |
687b81d0 | 1649 | of_i2c_register_devices(adap); |
55e71edb | 1650 | acpi_i2c_register_devices(adap); |
5d98e61d | 1651 | acpi_i2c_install_space_handler(adap); |
687b81d0 | 1652 | |
6e13e641 DB |
1653 | if (adap->nr < __i2c_first_dynamic_bus_num) |
1654 | i2c_scan_static_board_info(adap); | |
1655 | ||
4735c98f | 1656 | /* Notify drivers */ |
35fc37f8 | 1657 | mutex_lock(&core_lock); |
d6703281 | 1658 | bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); |
caada32a | 1659 | mutex_unlock(&core_lock); |
35fc37f8 JD |
1660 | |
1661 | return 0; | |
b119c6c9 | 1662 | |
b119c6c9 | 1663 | out_list: |
35fc37f8 | 1664 | mutex_lock(&core_lock); |
b119c6c9 | 1665 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 JD |
1666 | mutex_unlock(&core_lock); |
1667 | return res; | |
1da177e4 LT |
1668 | } |
1669 | ||
ee5c2744 DA |
1670 | /** |
1671 | * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 | |
1672 | * @adap: the adapter to register (with adap->nr initialized) | |
1673 | * Context: can sleep | |
1674 | * | |
1675 | * See i2c_add_numbered_adapter() for details. | |
1676 | */ | |
1677 | static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1678 | { | |
1679 | int id; | |
1680 | ||
1681 | mutex_lock(&core_lock); | |
1682 | id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, | |
1683 | GFP_KERNEL); | |
1684 | mutex_unlock(&core_lock); | |
1685 | if (id < 0) | |
1686 | return id == -ENOSPC ? -EBUSY : id; | |
1687 | ||
1688 | return i2c_register_adapter(adap); | |
1689 | } | |
1690 | ||
6e13e641 DB |
1691 | /** |
1692 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
1693 | * @adapter: the adapter to add | |
d64f73be | 1694 | * Context: can sleep |
6e13e641 DB |
1695 | * |
1696 | * This routine is used to declare an I2C adapter when its bus number | |
ee5c2744 DA |
1697 | * doesn't matter or when its bus number is specified by an dt alias. |
1698 | * Examples of bases when the bus number doesn't matter: I2C adapters | |
1699 | * dynamically added by USB links or PCI plugin cards. | |
6e13e641 DB |
1700 | * |
1701 | * When this returns zero, a new bus number was allocated and stored | |
1702 | * in adap->nr, and the specified adapter became available for clients. | |
1703 | * Otherwise, a negative errno value is returned. | |
1704 | */ | |
1705 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
1706 | { | |
ee5c2744 | 1707 | struct device *dev = &adapter->dev; |
4ae42b0f | 1708 | int id; |
6e13e641 | 1709 | |
ee5c2744 DA |
1710 | if (dev->of_node) { |
1711 | id = of_alias_get_id(dev->of_node, "i2c"); | |
1712 | if (id >= 0) { | |
1713 | adapter->nr = id; | |
1714 | return __i2c_add_numbered_adapter(adapter); | |
1715 | } | |
1716 | } | |
1717 | ||
caada32a | 1718 | mutex_lock(&core_lock); |
4ae42b0f TH |
1719 | id = idr_alloc(&i2c_adapter_idr, adapter, |
1720 | __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); | |
caada32a | 1721 | mutex_unlock(&core_lock); |
4ae42b0f TH |
1722 | if (id < 0) |
1723 | return id; | |
6e13e641 DB |
1724 | |
1725 | adapter->nr = id; | |
4ae42b0f | 1726 | |
6e13e641 DB |
1727 | return i2c_register_adapter(adapter); |
1728 | } | |
1729 | EXPORT_SYMBOL(i2c_add_adapter); | |
1730 | ||
1731 | /** | |
1732 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
1733 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 1734 | * Context: can sleep |
6e13e641 DB |
1735 | * |
1736 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
1737 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
1738 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
1739 | * is used to properly configure I2C devices. |
1740 | * | |
488bf314 GL |
1741 | * If the requested bus number is set to -1, then this function will behave |
1742 | * identically to i2c_add_adapter, and will dynamically assign a bus number. | |
1743 | * | |
6e13e641 DB |
1744 | * If no devices have pre-been declared for this bus, then be sure to |
1745 | * register the adapter before any dynamically allocated ones. Otherwise | |
1746 | * the required bus ID may not be available. | |
1747 | * | |
1748 | * When this returns zero, the specified adapter became available for | |
1749 | * clients using the bus number provided in adap->nr. Also, the table | |
1750 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
1751 | * and the appropriate driver model device nodes are created. Otherwise, a | |
1752 | * negative errno value is returned. | |
1753 | */ | |
1754 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1755 | { | |
488bf314 GL |
1756 | if (adap->nr == -1) /* -1 means dynamically assign bus id */ |
1757 | return i2c_add_adapter(adap); | |
6e13e641 | 1758 | |
ee5c2744 | 1759 | return __i2c_add_numbered_adapter(adap); |
6e13e641 DB |
1760 | } |
1761 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
1762 | ||
19baba4c | 1763 | static void i2c_do_del_adapter(struct i2c_driver *driver, |
69b0089a | 1764 | struct i2c_adapter *adapter) |
026526f5 | 1765 | { |
4735c98f | 1766 | struct i2c_client *client, *_n; |
026526f5 | 1767 | |
acec211c JD |
1768 | /* Remove the devices we created ourselves as the result of hardware |
1769 | * probing (using a driver's detect method) */ | |
4735c98f JD |
1770 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
1771 | if (client->adapter == adapter) { | |
1772 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", | |
1773 | client->name, client->addr); | |
1774 | list_del(&client->detected); | |
1775 | i2c_unregister_device(client); | |
1776 | } | |
1777 | } | |
026526f5 JD |
1778 | } |
1779 | ||
e549c2b5 | 1780 | static int __unregister_client(struct device *dev, void *dummy) |
5219bf88 JD |
1781 | { |
1782 | struct i2c_client *client = i2c_verify_client(dev); | |
1783 | if (client && strcmp(client->name, "dummy")) | |
1784 | i2c_unregister_device(client); | |
1785 | return 0; | |
1786 | } | |
1787 | ||
1788 | static int __unregister_dummy(struct device *dev, void *dummy) | |
e549c2b5 JD |
1789 | { |
1790 | struct i2c_client *client = i2c_verify_client(dev); | |
1791 | if (client) | |
1792 | i2c_unregister_device(client); | |
1793 | return 0; | |
1794 | } | |
1795 | ||
69b0089a JD |
1796 | static int __process_removed_adapter(struct device_driver *d, void *data) |
1797 | { | |
19baba4c LPC |
1798 | i2c_do_del_adapter(to_i2c_driver(d), data); |
1799 | return 0; | |
69b0089a JD |
1800 | } |
1801 | ||
d64f73be DB |
1802 | /** |
1803 | * i2c_del_adapter - unregister I2C adapter | |
1804 | * @adap: the adapter being unregistered | |
1805 | * Context: can sleep | |
1806 | * | |
1807 | * This unregisters an I2C adapter which was previously registered | |
1808 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
1809 | */ | |
71546300 | 1810 | void i2c_del_adapter(struct i2c_adapter *adap) |
1da177e4 | 1811 | { |
35fc37f8 | 1812 | struct i2c_adapter *found; |
bbd2d9c9 | 1813 | struct i2c_client *client, *next; |
1da177e4 LT |
1814 | |
1815 | /* First make sure that this adapter was ever added */ | |
35fc37f8 JD |
1816 | mutex_lock(&core_lock); |
1817 | found = idr_find(&i2c_adapter_idr, adap->nr); | |
1818 | mutex_unlock(&core_lock); | |
1819 | if (found != adap) { | |
b6d7b3d1 JD |
1820 | pr_debug("i2c-core: attempting to delete unregistered " |
1821 | "adapter [%s]\n", adap->name); | |
71546300 | 1822 | return; |
1da177e4 LT |
1823 | } |
1824 | ||
5d98e61d | 1825 | acpi_i2c_remove_space_handler(adap); |
026526f5 | 1826 | /* Tell drivers about this removal */ |
35fc37f8 | 1827 | mutex_lock(&core_lock); |
19baba4c | 1828 | bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 1829 | __process_removed_adapter); |
35fc37f8 | 1830 | mutex_unlock(&core_lock); |
1da177e4 | 1831 | |
bbd2d9c9 | 1832 | /* Remove devices instantiated from sysfs */ |
390946b1 JD |
1833 | mutex_lock_nested(&adap->userspace_clients_lock, |
1834 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1835 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1836 | detected) { | |
1837 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, | |
1838 | client->addr); | |
1839 | list_del(&client->detected); | |
1840 | i2c_unregister_device(client); | |
bbd2d9c9 | 1841 | } |
dafc50d1 | 1842 | mutex_unlock(&adap->userspace_clients_lock); |
bbd2d9c9 | 1843 | |
e549c2b5 | 1844 | /* Detach any active clients. This can't fail, thus we do not |
5219bf88 JD |
1845 | * check the returned value. This is a two-pass process, because |
1846 | * we can't remove the dummy devices during the first pass: they | |
1847 | * could have been instantiated by real devices wishing to clean | |
1848 | * them up properly, so we give them a chance to do that first. */ | |
19baba4c LPC |
1849 | device_for_each_child(&adap->dev, NULL, __unregister_client); |
1850 | device_for_each_child(&adap->dev, NULL, __unregister_dummy); | |
1da177e4 | 1851 | |
2bb5095a JD |
1852 | #ifdef CONFIG_I2C_COMPAT |
1853 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, | |
1854 | adap->dev.parent); | |
1855 | #endif | |
1856 | ||
c5567521 TLSC |
1857 | /* device name is gone after device_unregister */ |
1858 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); | |
1859 | ||
9f924169 WS |
1860 | pm_runtime_disable(&adap->dev); |
1861 | ||
26680ee2 WS |
1862 | /* wait until all references to the device are gone |
1863 | * | |
1864 | * FIXME: This is old code and should ideally be replaced by an | |
1865 | * alternative which results in decoupling the lifetime of the struct | |
1866 | * device from the i2c_adapter, like spi or netdev do. Any solution | |
95cc1e3d | 1867 | * should be thoroughly tested with DEBUG_KOBJECT_RELEASE enabled! |
26680ee2 | 1868 | */ |
1da177e4 | 1869 | init_completion(&adap->dev_released); |
1da177e4 | 1870 | device_unregister(&adap->dev); |
1da177e4 | 1871 | wait_for_completion(&adap->dev_released); |
1da177e4 | 1872 | |
6e13e641 | 1873 | /* free bus id */ |
35fc37f8 | 1874 | mutex_lock(&core_lock); |
1da177e4 | 1875 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 | 1876 | mutex_unlock(&core_lock); |
1da177e4 | 1877 | |
bd4bc3db JD |
1878 | /* Clear the device structure in case this adapter is ever going to be |
1879 | added again */ | |
1880 | memset(&adap->dev, 0, sizeof(adap->dev)); | |
1da177e4 | 1881 | } |
c0564606 | 1882 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 | 1883 | |
54177ccf WS |
1884 | /** |
1885 | * i2c_parse_fw_timings - get I2C related timing parameters from firmware | |
1886 | * @dev: The device to scan for I2C timing properties | |
1887 | * @t: the i2c_timings struct to be filled with values | |
1888 | * @use_defaults: bool to use sane defaults derived from the I2C specification | |
1889 | * when properties are not found, otherwise use 0 | |
1890 | * | |
1891 | * Scan the device for the generic I2C properties describing timing parameters | |
1892 | * for the signal and fill the given struct with the results. If a property was | |
1893 | * not found and use_defaults was true, then maximum timings are assumed which | |
1894 | * are derived from the I2C specification. If use_defaults is not used, the | |
1895 | * results will be 0, so drivers can apply their own defaults later. The latter | |
1896 | * is mainly intended for avoiding regressions of existing drivers which want | |
1897 | * to switch to this function. New drivers almost always should use the defaults. | |
1898 | */ | |
1899 | ||
1900 | void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults) | |
1901 | { | |
1902 | int ret; | |
1903 | ||
1904 | memset(t, 0, sizeof(*t)); | |
1905 | ||
1906 | ret = device_property_read_u32(dev, "clock-frequency", &t->bus_freq_hz); | |
1907 | if (ret && use_defaults) | |
1908 | t->bus_freq_hz = 100000; | |
1909 | ||
1910 | ret = device_property_read_u32(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns); | |
1911 | if (ret && use_defaults) { | |
1912 | if (t->bus_freq_hz <= 100000) | |
1913 | t->scl_rise_ns = 1000; | |
1914 | else if (t->bus_freq_hz <= 400000) | |
1915 | t->scl_rise_ns = 300; | |
1916 | else | |
1917 | t->scl_rise_ns = 120; | |
1918 | } | |
1919 | ||
1920 | ret = device_property_read_u32(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns); | |
1921 | if (ret && use_defaults) { | |
1922 | if (t->bus_freq_hz <= 400000) | |
1923 | t->scl_fall_ns = 300; | |
1924 | else | |
1925 | t->scl_fall_ns = 120; | |
1926 | } | |
1927 | ||
1928 | device_property_read_u32(dev, "i2c-scl-internal-delay-ns", &t->scl_int_delay_ns); | |
1929 | ||
1930 | ret = device_property_read_u32(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns); | |
1931 | if (ret && use_defaults) | |
1932 | t->sda_fall_ns = t->scl_fall_ns; | |
1933 | } | |
1934 | EXPORT_SYMBOL_GPL(i2c_parse_fw_timings); | |
1935 | ||
7b4fbc50 DB |
1936 | /* ------------------------------------------------------------------------- */ |
1937 | ||
7ae31482 JD |
1938 | int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)) |
1939 | { | |
1940 | int res; | |
1941 | ||
1942 | mutex_lock(&core_lock); | |
1943 | res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); | |
1944 | mutex_unlock(&core_lock); | |
1945 | ||
1946 | return res; | |
1947 | } | |
1948 | EXPORT_SYMBOL_GPL(i2c_for_each_dev); | |
1949 | ||
69b0089a | 1950 | static int __process_new_driver(struct device *dev, void *data) |
7f101a97 | 1951 | { |
4f8cf824 JD |
1952 | if (dev->type != &i2c_adapter_type) |
1953 | return 0; | |
69b0089a | 1954 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
7f101a97 DY |
1955 | } |
1956 | ||
7b4fbc50 DB |
1957 | /* |
1958 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
729d6dd5 | 1959 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
1da177e4 LT |
1960 | */ |
1961 | ||
de59cf9e | 1962 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 1963 | { |
7eebcb7c | 1964 | int res; |
1da177e4 | 1965 | |
1d0b19c9 | 1966 | /* Can't register until after driver model init */ |
95026658 | 1967 | if (WARN_ON(!is_registered)) |
1d0b19c9 DB |
1968 | return -EAGAIN; |
1969 | ||
1da177e4 | 1970 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 1971 | driver->driver.owner = owner; |
1da177e4 | 1972 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 1973 | |
729d6dd5 | 1974 | /* When registration returns, the driver core |
6e13e641 DB |
1975 | * will have called probe() for all matching-but-unbound devices. |
1976 | */ | |
1da177e4 LT |
1977 | res = driver_register(&driver->driver); |
1978 | if (res) | |
7eebcb7c | 1979 | return res; |
438d6c2c | 1980 | |
35d8b2e6 | 1981 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 1982 | |
4735c98f JD |
1983 | INIT_LIST_HEAD(&driver->clients); |
1984 | /* Walk the adapters that are already present */ | |
7ae31482 | 1985 | i2c_for_each_dev(driver, __process_new_driver); |
35fc37f8 | 1986 | |
7f101a97 DY |
1987 | return 0; |
1988 | } | |
1989 | EXPORT_SYMBOL(i2c_register_driver); | |
1990 | ||
69b0089a | 1991 | static int __process_removed_driver(struct device *dev, void *data) |
7f101a97 | 1992 | { |
19baba4c LPC |
1993 | if (dev->type == &i2c_adapter_type) |
1994 | i2c_do_del_adapter(data, to_i2c_adapter(dev)); | |
1995 | return 0; | |
1da177e4 LT |
1996 | } |
1997 | ||
a1d9e6e4 DB |
1998 | /** |
1999 | * i2c_del_driver - unregister I2C driver | |
2000 | * @driver: the driver being unregistered | |
d64f73be | 2001 | * Context: can sleep |
a1d9e6e4 | 2002 | */ |
b3e82096 | 2003 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 2004 | { |
7ae31482 | 2005 | i2c_for_each_dev(driver, __process_removed_driver); |
1da177e4 LT |
2006 | |
2007 | driver_unregister(&driver->driver); | |
35d8b2e6 | 2008 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 2009 | } |
c0564606 | 2010 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 2011 | |
7b4fbc50 DB |
2012 | /* ------------------------------------------------------------------------- */ |
2013 | ||
e48d3319 JD |
2014 | /** |
2015 | * i2c_use_client - increments the reference count of the i2c client structure | |
2016 | * @client: the client being referenced | |
2017 | * | |
2018 | * Each live reference to a client should be refcounted. The driver model does | |
2019 | * that automatically as part of driver binding, so that most drivers don't | |
2020 | * need to do this explicitly: they hold a reference until they're unbound | |
2021 | * from the device. | |
2022 | * | |
2023 | * A pointer to the client with the incremented reference counter is returned. | |
2024 | */ | |
2025 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 2026 | { |
6ea438ec DB |
2027 | if (client && get_device(&client->dev)) |
2028 | return client; | |
2029 | return NULL; | |
1da177e4 | 2030 | } |
c0564606 | 2031 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 2032 | |
e48d3319 JD |
2033 | /** |
2034 | * i2c_release_client - release a use of the i2c client structure | |
2035 | * @client: the client being no longer referenced | |
2036 | * | |
2037 | * Must be called when a user of a client is finished with it. | |
2038 | */ | |
2039 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 2040 | { |
6ea438ec DB |
2041 | if (client) |
2042 | put_device(&client->dev); | |
1da177e4 | 2043 | } |
c0564606 | 2044 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 2045 | |
9b766b81 DB |
2046 | struct i2c_cmd_arg { |
2047 | unsigned cmd; | |
2048 | void *arg; | |
2049 | }; | |
2050 | ||
2051 | static int i2c_cmd(struct device *dev, void *_arg) | |
2052 | { | |
2053 | struct i2c_client *client = i2c_verify_client(dev); | |
2054 | struct i2c_cmd_arg *arg = _arg; | |
0acc2b32 LPC |
2055 | struct i2c_driver *driver; |
2056 | ||
2057 | if (!client || !client->dev.driver) | |
2058 | return 0; | |
9b766b81 | 2059 | |
0acc2b32 LPC |
2060 | driver = to_i2c_driver(client->dev.driver); |
2061 | if (driver->command) | |
2062 | driver->command(client, arg->cmd, arg->arg); | |
9b766b81 DB |
2063 | return 0; |
2064 | } | |
2065 | ||
1da177e4 LT |
2066 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
2067 | { | |
9b766b81 | 2068 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 2069 | |
9b766b81 DB |
2070 | cmd_arg.cmd = cmd; |
2071 | cmd_arg.arg = arg; | |
2072 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 2073 | } |
c0564606 | 2074 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 | 2075 | |
ea7513bb PA |
2076 | #if IS_ENABLED(CONFIG_OF_DYNAMIC) |
2077 | static int of_i2c_notify(struct notifier_block *nb, unsigned long action, | |
2078 | void *arg) | |
2079 | { | |
2080 | struct of_reconfig_data *rd = arg; | |
2081 | struct i2c_adapter *adap; | |
2082 | struct i2c_client *client; | |
2083 | ||
2084 | switch (of_reconfig_get_state_change(action, rd)) { | |
2085 | case OF_RECONFIG_CHANGE_ADD: | |
2086 | adap = of_find_i2c_adapter_by_node(rd->dn->parent); | |
2087 | if (adap == NULL) | |
2088 | return NOTIFY_OK; /* not for us */ | |
2089 | ||
4f001fd3 PA |
2090 | if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) { |
2091 | put_device(&adap->dev); | |
2092 | return NOTIFY_OK; | |
2093 | } | |
2094 | ||
ea7513bb PA |
2095 | client = of_i2c_register_device(adap, rd->dn); |
2096 | put_device(&adap->dev); | |
2097 | ||
2098 | if (IS_ERR(client)) { | |
2099 | pr_err("%s: failed to create for '%s'\n", | |
2100 | __func__, rd->dn->full_name); | |
2101 | return notifier_from_errno(PTR_ERR(client)); | |
2102 | } | |
2103 | break; | |
2104 | case OF_RECONFIG_CHANGE_REMOVE: | |
4f001fd3 PA |
2105 | /* already depopulated? */ |
2106 | if (!of_node_check_flag(rd->dn, OF_POPULATED)) | |
2107 | return NOTIFY_OK; | |
2108 | ||
ea7513bb PA |
2109 | /* find our device by node */ |
2110 | client = of_find_i2c_device_by_node(rd->dn); | |
2111 | if (client == NULL) | |
2112 | return NOTIFY_OK; /* no? not meant for us */ | |
2113 | ||
2114 | /* unregister takes one ref away */ | |
2115 | i2c_unregister_device(client); | |
2116 | ||
2117 | /* and put the reference of the find */ | |
2118 | put_device(&client->dev); | |
2119 | break; | |
2120 | } | |
2121 | ||
2122 | return NOTIFY_OK; | |
2123 | } | |
2124 | static struct notifier_block i2c_of_notifier = { | |
2125 | .notifier_call = of_i2c_notify, | |
2126 | }; | |
2127 | #else | |
2128 | extern struct notifier_block i2c_of_notifier; | |
2129 | #endif /* CONFIG_OF_DYNAMIC */ | |
2130 | ||
1da177e4 LT |
2131 | static int __init i2c_init(void) |
2132 | { | |
2133 | int retval; | |
2134 | ||
03bde7c3 WS |
2135 | retval = of_alias_get_highest_id("i2c"); |
2136 | ||
2137 | down_write(&__i2c_board_lock); | |
2138 | if (retval >= __i2c_first_dynamic_bus_num) | |
2139 | __i2c_first_dynamic_bus_num = retval + 1; | |
2140 | up_write(&__i2c_board_lock); | |
2141 | ||
1da177e4 | 2142 | retval = bus_register(&i2c_bus_type); |
1da177e4 LT |
2143 | if (retval) |
2144 | return retval; | |
b980a26d WS |
2145 | |
2146 | is_registered = true; | |
2147 | ||
2bb5095a JD |
2148 | #ifdef CONFIG_I2C_COMPAT |
2149 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); | |
2150 | if (!i2c_adapter_compat_class) { | |
2151 | retval = -ENOMEM; | |
2152 | goto bus_err; | |
2153 | } | |
2154 | #endif | |
e9f1373b DB |
2155 | retval = i2c_add_driver(&dummy_driver); |
2156 | if (retval) | |
2bb5095a | 2157 | goto class_err; |
ea7513bb PA |
2158 | |
2159 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) | |
2160 | WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier)); | |
2161 | ||
e9f1373b DB |
2162 | return 0; |
2163 | ||
2bb5095a JD |
2164 | class_err: |
2165 | #ifdef CONFIG_I2C_COMPAT | |
2166 | class_compat_unregister(i2c_adapter_compat_class); | |
e9f1373b | 2167 | bus_err: |
2bb5095a | 2168 | #endif |
b980a26d | 2169 | is_registered = false; |
e9f1373b DB |
2170 | bus_unregister(&i2c_bus_type); |
2171 | return retval; | |
1da177e4 LT |
2172 | } |
2173 | ||
2174 | static void __exit i2c_exit(void) | |
2175 | { | |
ea7513bb PA |
2176 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) |
2177 | WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier)); | |
e9f1373b | 2178 | i2c_del_driver(&dummy_driver); |
2bb5095a JD |
2179 | #ifdef CONFIG_I2C_COMPAT |
2180 | class_compat_unregister(i2c_adapter_compat_class); | |
2181 | #endif | |
1da177e4 | 2182 | bus_unregister(&i2c_bus_type); |
d9a83d62 | 2183 | tracepoint_synchronize_unregister(); |
1da177e4 LT |
2184 | } |
2185 | ||
a10f9e7c DB |
2186 | /* We must initialize early, because some subsystems register i2c drivers |
2187 | * in subsys_initcall() code, but are linked (and initialized) before i2c. | |
2188 | */ | |
2189 | postcore_initcall(i2c_init); | |
1da177e4 LT |
2190 | module_exit(i2c_exit); |
2191 | ||
2192 | /* ---------------------------------------------------- | |
2193 | * the functional interface to the i2c busses. | |
2194 | * ---------------------------------------------------- | |
2195 | */ | |
2196 | ||
b7f62584 WS |
2197 | /* Check if val is exceeding the quirk IFF quirk is non 0 */ |
2198 | #define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) | |
2199 | ||
2200 | static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) | |
2201 | { | |
2202 | dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n", | |
2203 | err_msg, msg->addr, msg->len, | |
2204 | msg->flags & I2C_M_RD ? "read" : "write"); | |
2205 | return -EOPNOTSUPP; | |
2206 | } | |
2207 | ||
2208 | static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
2209 | { | |
2210 | const struct i2c_adapter_quirks *q = adap->quirks; | |
2211 | int max_num = q->max_num_msgs, i; | |
2212 | bool do_len_check = true; | |
2213 | ||
2214 | if (q->flags & I2C_AQ_COMB) { | |
2215 | max_num = 2; | |
2216 | ||
2217 | /* special checks for combined messages */ | |
2218 | if (num == 2) { | |
2219 | if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD) | |
2220 | return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write"); | |
2221 | ||
2222 | if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD)) | |
2223 | return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read"); | |
2224 | ||
2225 | if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr) | |
2226 | return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr"); | |
2227 | ||
2228 | if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len)) | |
2229 | return i2c_quirk_error(adap, &msgs[0], "msg too long"); | |
2230 | ||
2231 | if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len)) | |
2232 | return i2c_quirk_error(adap, &msgs[1], "msg too long"); | |
2233 | ||
2234 | do_len_check = false; | |
2235 | } | |
2236 | } | |
2237 | ||
2238 | if (i2c_quirk_exceeded(num, max_num)) | |
2239 | return i2c_quirk_error(adap, &msgs[0], "too many messages"); | |
2240 | ||
2241 | for (i = 0; i < num; i++) { | |
2242 | u16 len = msgs[i].len; | |
2243 | ||
2244 | if (msgs[i].flags & I2C_M_RD) { | |
2245 | if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len)) | |
2246 | return i2c_quirk_error(adap, &msgs[i], "msg too long"); | |
2247 | } else { | |
2248 | if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len)) | |
2249 | return i2c_quirk_error(adap, &msgs[i], "msg too long"); | |
2250 | } | |
2251 | } | |
2252 | ||
2253 | return 0; | |
2254 | } | |
2255 | ||
b37d2a3a JD |
2256 | /** |
2257 | * __i2c_transfer - unlocked flavor of i2c_transfer | |
2258 | * @adap: Handle to I2C bus | |
2259 | * @msgs: One or more messages to execute before STOP is issued to | |
2260 | * terminate the operation; each message begins with a START. | |
2261 | * @num: Number of messages to be executed. | |
2262 | * | |
2263 | * Returns negative errno, else the number of messages executed. | |
2264 | * | |
2265 | * Adapter lock must be held when calling this function. No debug logging | |
2266 | * takes place. adap->algo->master_xfer existence isn't checked. | |
2267 | */ | |
2268 | int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
2269 | { | |
2270 | unsigned long orig_jiffies; | |
2271 | int ret, try; | |
2272 | ||
b7f62584 WS |
2273 | if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) |
2274 | return -EOPNOTSUPP; | |
2275 | ||
d9a83d62 DH |
2276 | /* i2c_trace_msg gets enabled when tracepoint i2c_transfer gets |
2277 | * enabled. This is an efficient way of keeping the for-loop from | |
2278 | * being executed when not needed. | |
2279 | */ | |
2280 | if (static_key_false(&i2c_trace_msg)) { | |
2281 | int i; | |
2282 | for (i = 0; i < num; i++) | |
2283 | if (msgs[i].flags & I2C_M_RD) | |
2284 | trace_i2c_read(adap, &msgs[i], i); | |
2285 | else | |
2286 | trace_i2c_write(adap, &msgs[i], i); | |
2287 | } | |
2288 | ||
b37d2a3a JD |
2289 | /* Retry automatically on arbitration loss */ |
2290 | orig_jiffies = jiffies; | |
2291 | for (ret = 0, try = 0; try <= adap->retries; try++) { | |
2292 | ret = adap->algo->master_xfer(adap, msgs, num); | |
2293 | if (ret != -EAGAIN) | |
2294 | break; | |
2295 | if (time_after(jiffies, orig_jiffies + adap->timeout)) | |
2296 | break; | |
2297 | } | |
2298 | ||
d9a83d62 DH |
2299 | if (static_key_false(&i2c_trace_msg)) { |
2300 | int i; | |
2301 | for (i = 0; i < ret; i++) | |
2302 | if (msgs[i].flags & I2C_M_RD) | |
2303 | trace_i2c_reply(adap, &msgs[i], i); | |
2304 | trace_i2c_result(adap, i, ret); | |
2305 | } | |
2306 | ||
b37d2a3a JD |
2307 | return ret; |
2308 | } | |
2309 | EXPORT_SYMBOL(__i2c_transfer); | |
2310 | ||
a1cdedac DB |
2311 | /** |
2312 | * i2c_transfer - execute a single or combined I2C message | |
2313 | * @adap: Handle to I2C bus | |
2314 | * @msgs: One or more messages to execute before STOP is issued to | |
2315 | * terminate the operation; each message begins with a START. | |
2316 | * @num: Number of messages to be executed. | |
2317 | * | |
2318 | * Returns negative errno, else the number of messages executed. | |
2319 | * | |
2320 | * Note that there is no requirement that each message be sent to | |
2321 | * the same slave address, although that is the most common model. | |
2322 | */ | |
09b8ce0a | 2323 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
1da177e4 | 2324 | { |
b37d2a3a | 2325 | int ret; |
1da177e4 | 2326 | |
a1cdedac DB |
2327 | /* REVISIT the fault reporting model here is weak: |
2328 | * | |
2329 | * - When we get an error after receiving N bytes from a slave, | |
2330 | * there is no way to report "N". | |
2331 | * | |
2332 | * - When we get a NAK after transmitting N bytes to a slave, | |
2333 | * there is no way to report "N" ... or to let the master | |
2334 | * continue executing the rest of this combined message, if | |
2335 | * that's the appropriate response. | |
2336 | * | |
2337 | * - When for example "num" is two and we successfully complete | |
2338 | * the first message but get an error part way through the | |
2339 | * second, it's unclear whether that should be reported as | |
2340 | * one (discarding status on the second message) or errno | |
2341 | * (discarding status on the first one). | |
2342 | */ | |
2343 | ||
1da177e4 LT |
2344 | if (adap->algo->master_xfer) { |
2345 | #ifdef DEBUG | |
2346 | for (ret = 0; ret < num; ret++) { | |
2347 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
2348 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
2349 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
2350 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
2351 | } |
2352 | #endif | |
2353 | ||
cea443a8 | 2354 | if (in_atomic() || irqs_disabled()) { |
8320f495 | 2355 | ret = adap->trylock_bus(adap, I2C_LOCK_SEGMENT); |
cea443a8 MR |
2356 | if (!ret) |
2357 | /* I2C activity is ongoing. */ | |
2358 | return -EAGAIN; | |
2359 | } else { | |
8320f495 | 2360 | i2c_lock_bus(adap, I2C_LOCK_SEGMENT); |
cea443a8 MR |
2361 | } |
2362 | ||
b37d2a3a | 2363 | ret = __i2c_transfer(adap, msgs, num); |
8320f495 | 2364 | i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); |
1da177e4 LT |
2365 | |
2366 | return ret; | |
2367 | } else { | |
2368 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
24a5bb7b | 2369 | return -EOPNOTSUPP; |
1da177e4 LT |
2370 | } |
2371 | } | |
c0564606 | 2372 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 | 2373 | |
a1cdedac DB |
2374 | /** |
2375 | * i2c_master_send - issue a single I2C message in master transmit mode | |
2376 | * @client: Handle to slave device | |
2377 | * @buf: Data that will be written to the slave | |
0c43ea54 | 2378 | * @count: How many bytes to write, must be less than 64k since msg.len is u16 |
a1cdedac DB |
2379 | * |
2380 | * Returns negative errno, or else the number of bytes written. | |
2381 | */ | |
0cc43a18 | 2382 | int i2c_master_send(const struct i2c_client *client, const char *buf, int count) |
1da177e4 LT |
2383 | { |
2384 | int ret; | |
7225acf4 | 2385 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
2386 | struct i2c_msg msg; |
2387 | ||
815f55f2 JD |
2388 | msg.addr = client->addr; |
2389 | msg.flags = client->flags & I2C_M_TEN; | |
2390 | msg.len = count; | |
2391 | msg.buf = (char *)buf; | |
438d6c2c | 2392 | |
815f55f2 | 2393 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 2394 | |
834aa6f3 WS |
2395 | /* |
2396 | * If everything went ok (i.e. 1 msg transmitted), return #bytes | |
2397 | * transmitted, else error code. | |
2398 | */ | |
815f55f2 | 2399 | return (ret == 1) ? count : ret; |
1da177e4 | 2400 | } |
c0564606 | 2401 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 | 2402 | |
a1cdedac DB |
2403 | /** |
2404 | * i2c_master_recv - issue a single I2C message in master receive mode | |
2405 | * @client: Handle to slave device | |
2406 | * @buf: Where to store data read from slave | |
0c43ea54 | 2407 | * @count: How many bytes to read, must be less than 64k since msg.len is u16 |
a1cdedac DB |
2408 | * |
2409 | * Returns negative errno, or else the number of bytes read. | |
2410 | */ | |
0cc43a18 | 2411 | int i2c_master_recv(const struct i2c_client *client, char *buf, int count) |
1da177e4 | 2412 | { |
7225acf4 | 2413 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
2414 | struct i2c_msg msg; |
2415 | int ret; | |
815f55f2 JD |
2416 | |
2417 | msg.addr = client->addr; | |
2418 | msg.flags = client->flags & I2C_M_TEN; | |
2419 | msg.flags |= I2C_M_RD; | |
2420 | msg.len = count; | |
2421 | msg.buf = buf; | |
2422 | ||
2423 | ret = i2c_transfer(adap, &msg, 1); | |
2424 | ||
834aa6f3 WS |
2425 | /* |
2426 | * If everything went ok (i.e. 1 msg received), return #bytes received, | |
2427 | * else error code. | |
2428 | */ | |
815f55f2 | 2429 | return (ret == 1) ? count : ret; |
1da177e4 | 2430 | } |
c0564606 | 2431 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 2432 | |
1da177e4 LT |
2433 | /* ---------------------------------------------------- |
2434 | * the i2c address scanning function | |
2435 | * Will not work for 10-bit addresses! | |
2436 | * ---------------------------------------------------- | |
2437 | */ | |
1da177e4 | 2438 | |
63e4e802 JD |
2439 | /* |
2440 | * Legacy default probe function, mostly relevant for SMBus. The default | |
2441 | * probe method is a quick write, but it is known to corrupt the 24RF08 | |
2442 | * EEPROMs due to a state machine bug, and could also irreversibly | |
2443 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, | |
2444 | * we use a short byte read instead. Also, some bus drivers don't implement | |
2445 | * quick write, so we fallback to a byte read in that case too. | |
2446 | * On x86, there is another special case for FSC hardware monitoring chips, | |
2447 | * which want regular byte reads (address 0x73.) Fortunately, these are the | |
2448 | * only known chips using this I2C address on PC hardware. | |
2449 | * Returns 1 if probe succeeded, 0 if not. | |
2450 | */ | |
2451 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) | |
2452 | { | |
2453 | int err; | |
2454 | union i2c_smbus_data dummy; | |
2455 | ||
2456 | #ifdef CONFIG_X86 | |
2457 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) | |
2458 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
2459 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2460 | I2C_SMBUS_BYTE_DATA, &dummy); | |
2461 | else | |
2462 | #endif | |
8031d79b JD |
2463 | if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) |
2464 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) | |
63e4e802 JD |
2465 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, |
2466 | I2C_SMBUS_QUICK, NULL); | |
8031d79b JD |
2467 | else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) |
2468 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2469 | I2C_SMBUS_BYTE, &dummy); | |
2470 | else { | |
d63a9e85 AL |
2471 | dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", |
2472 | addr); | |
8031d79b JD |
2473 | err = -EOPNOTSUPP; |
2474 | } | |
63e4e802 JD |
2475 | |
2476 | return err >= 0; | |
2477 | } | |
2478 | ||
ccfbbd08 | 2479 | static int i2c_detect_address(struct i2c_client *temp_client, |
4735c98f JD |
2480 | struct i2c_driver *driver) |
2481 | { | |
2482 | struct i2c_board_info info; | |
2483 | struct i2c_adapter *adapter = temp_client->adapter; | |
2484 | int addr = temp_client->addr; | |
2485 | int err; | |
2486 | ||
2487 | /* Make sure the address is valid */ | |
66be6056 | 2488 | err = i2c_check_7bit_addr_validity_strict(addr); |
656b8761 | 2489 | if (err) { |
4735c98f JD |
2490 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
2491 | addr); | |
656b8761 | 2492 | return err; |
4735c98f JD |
2493 | } |
2494 | ||
9bccc70a | 2495 | /* Skip if already in use (7 bit, no need to encode flags) */ |
3b5f794b | 2496 | if (i2c_check_addr_busy(adapter, addr)) |
4735c98f JD |
2497 | return 0; |
2498 | ||
ccfbbd08 | 2499 | /* Make sure there is something at this address */ |
63e4e802 JD |
2500 | if (!i2c_default_probe(adapter, addr)) |
2501 | return 0; | |
4735c98f JD |
2502 | |
2503 | /* Finally call the custom detection function */ | |
2504 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
2505 | info.addr = addr; | |
310ec792 | 2506 | err = driver->detect(temp_client, &info); |
4735c98f JD |
2507 | if (err) { |
2508 | /* -ENODEV is returned if the detection fails. We catch it | |
2509 | here as this isn't an error. */ | |
2510 | return err == -ENODEV ? 0 : err; | |
2511 | } | |
2512 | ||
2513 | /* Consistency check */ | |
2514 | if (info.type[0] == '\0') { | |
2515 | dev_err(&adapter->dev, "%s detection function provided " | |
2516 | "no name for 0x%x\n", driver->driver.name, | |
2517 | addr); | |
2518 | } else { | |
2519 | struct i2c_client *client; | |
2520 | ||
2521 | /* Detection succeeded, instantiate the device */ | |
0c176170 WS |
2522 | if (adapter->class & I2C_CLASS_DEPRECATED) |
2523 | dev_warn(&adapter->dev, | |
2524 | "This adapter will soon drop class based instantiation of devices. " | |
2525 | "Please make sure client 0x%02x gets instantiated by other means. " | |
2526 | "Check 'Documentation/i2c/instantiating-devices' for details.\n", | |
2527 | info.addr); | |
2528 | ||
4735c98f JD |
2529 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", |
2530 | info.type, info.addr); | |
2531 | client = i2c_new_device(adapter, &info); | |
2532 | if (client) | |
2533 | list_add_tail(&client->detected, &driver->clients); | |
2534 | else | |
2535 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", | |
2536 | info.type, info.addr); | |
2537 | } | |
2538 | return 0; | |
2539 | } | |
2540 | ||
2541 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) | |
2542 | { | |
c3813d6a | 2543 | const unsigned short *address_list; |
4735c98f JD |
2544 | struct i2c_client *temp_client; |
2545 | int i, err = 0; | |
2546 | int adap_id = i2c_adapter_id(adapter); | |
2547 | ||
c3813d6a JD |
2548 | address_list = driver->address_list; |
2549 | if (!driver->detect || !address_list) | |
4735c98f JD |
2550 | return 0; |
2551 | ||
45552272 WS |
2552 | /* Warn that the adapter lost class based instantiation */ |
2553 | if (adapter->class == I2C_CLASS_DEPRECATED) { | |
2554 | dev_dbg(&adapter->dev, | |
2555 | "This adapter dropped support for I2C classes and " | |
2556 | "won't auto-detect %s devices anymore. If you need it, check " | |
2557 | "'Documentation/i2c/instantiating-devices' for alternatives.\n", | |
2558 | driver->driver.name); | |
2559 | return 0; | |
2560 | } | |
2561 | ||
51b54ba9 JD |
2562 | /* Stop here if the classes do not match */ |
2563 | if (!(adapter->class & driver->class)) | |
2564 | return 0; | |
2565 | ||
4735c98f JD |
2566 | /* Set up a temporary client to help detect callback */ |
2567 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); | |
2568 | if (!temp_client) | |
2569 | return -ENOMEM; | |
2570 | temp_client->adapter = adapter; | |
2571 | ||
c3813d6a | 2572 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
4735c98f | 2573 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
c3813d6a JD |
2574 | "addr 0x%02x\n", adap_id, address_list[i]); |
2575 | temp_client->addr = address_list[i]; | |
ccfbbd08 | 2576 | err = i2c_detect_address(temp_client, driver); |
51b54ba9 JD |
2577 | if (unlikely(err)) |
2578 | break; | |
4735c98f JD |
2579 | } |
2580 | ||
4735c98f JD |
2581 | kfree(temp_client); |
2582 | return err; | |
2583 | } | |
2584 | ||
d44f19d5 JD |
2585 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
2586 | { | |
2587 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2588 | I2C_SMBUS_QUICK, NULL) >= 0; | |
2589 | } | |
2590 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); | |
2591 | ||
12b5053a JD |
2592 | struct i2c_client * |
2593 | i2c_new_probed_device(struct i2c_adapter *adap, | |
2594 | struct i2c_board_info *info, | |
9a94241a JD |
2595 | unsigned short const *addr_list, |
2596 | int (*probe)(struct i2c_adapter *, unsigned short addr)) | |
12b5053a JD |
2597 | { |
2598 | int i; | |
2599 | ||
8031d79b | 2600 | if (!probe) |
9a94241a | 2601 | probe = i2c_default_probe; |
12b5053a | 2602 | |
12b5053a JD |
2603 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
2604 | /* Check address validity */ | |
66be6056 | 2605 | if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) { |
12b5053a JD |
2606 | dev_warn(&adap->dev, "Invalid 7-bit address " |
2607 | "0x%02x\n", addr_list[i]); | |
2608 | continue; | |
2609 | } | |
2610 | ||
9bccc70a | 2611 | /* Check address availability (7 bit, no need to encode flags) */ |
3b5f794b | 2612 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
12b5053a JD |
2613 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
2614 | "use, not probing\n", addr_list[i]); | |
2615 | continue; | |
2616 | } | |
2617 | ||
63e4e802 | 2618 | /* Test address responsiveness */ |
9a94241a | 2619 | if (probe(adap, addr_list[i])) |
63e4e802 | 2620 | break; |
12b5053a | 2621 | } |
12b5053a JD |
2622 | |
2623 | if (addr_list[i] == I2C_CLIENT_END) { | |
2624 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
2625 | return NULL; | |
2626 | } | |
2627 | ||
2628 | info->addr = addr_list[i]; | |
2629 | return i2c_new_device(adap, info); | |
2630 | } | |
2631 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
2632 | ||
d735b34d | 2633 | struct i2c_adapter *i2c_get_adapter(int nr) |
1da177e4 | 2634 | { |
1da177e4 | 2635 | struct i2c_adapter *adapter; |
438d6c2c | 2636 | |
caada32a | 2637 | mutex_lock(&core_lock); |
d735b34d | 2638 | adapter = idr_find(&i2c_adapter_idr, nr); |
611e12ea VZ |
2639 | if (!adapter) |
2640 | goto exit; | |
2641 | ||
2642 | if (try_module_get(adapter->owner)) | |
2643 | get_device(&adapter->dev); | |
2644 | else | |
a0920e10 MH |
2645 | adapter = NULL; |
2646 | ||
611e12ea | 2647 | exit: |
caada32a | 2648 | mutex_unlock(&core_lock); |
a0920e10 | 2649 | return adapter; |
1da177e4 | 2650 | } |
c0564606 | 2651 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
2652 | |
2653 | void i2c_put_adapter(struct i2c_adapter *adap) | |
2654 | { | |
611e12ea VZ |
2655 | if (!adap) |
2656 | return; | |
2657 | ||
2658 | put_device(&adap->dev); | |
2659 | module_put(adap->owner); | |
1da177e4 | 2660 | } |
c0564606 | 2661 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
2662 | |
2663 | /* The SMBus parts */ | |
2664 | ||
438d6c2c | 2665 | #define POLY (0x1070U << 3) |
09b8ce0a | 2666 | static u8 crc8(u16 data) |
1da177e4 LT |
2667 | { |
2668 | int i; | |
438d6c2c | 2669 | |
7225acf4 | 2670 | for (i = 0; i < 8; i++) { |
438d6c2c | 2671 | if (data & 0x8000) |
1da177e4 LT |
2672 | data = data ^ POLY; |
2673 | data = data << 1; | |
2674 | } | |
2675 | return (u8)(data >> 8); | |
2676 | } | |
2677 | ||
421ef47b JD |
2678 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
2679 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
2680 | { |
2681 | int i; | |
2682 | ||
7225acf4 | 2683 | for (i = 0; i < count; i++) |
421ef47b | 2684 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
2685 | return crc; |
2686 | } | |
2687 | ||
421ef47b JD |
2688 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
2689 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 2690 | { |
421ef47b | 2691 | /* The address will be sent first */ |
041edda8 | 2692 | u8 addr = i2c_8bit_addr_from_msg(msg); |
421ef47b JD |
2693 | pec = i2c_smbus_pec(pec, &addr, 1); |
2694 | ||
2695 | /* The data buffer follows */ | |
2696 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
2697 | } |
2698 | ||
421ef47b JD |
2699 | /* Used for write only transactions */ |
2700 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 2701 | { |
421ef47b JD |
2702 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
2703 | msg->len++; | |
1da177e4 LT |
2704 | } |
2705 | ||
421ef47b JD |
2706 | /* Return <0 on CRC error |
2707 | If there was a write before this read (most cases) we need to take the | |
2708 | partial CRC from the write part into account. | |
2709 | Note that this function does modify the message (we need to decrease the | |
2710 | message length to hide the CRC byte from the caller). */ | |
2711 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 2712 | { |
421ef47b JD |
2713 | u8 rpec = msg->buf[--msg->len]; |
2714 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 2715 | |
1da177e4 LT |
2716 | if (rpec != cpec) { |
2717 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
2718 | rpec, cpec); | |
24a5bb7b | 2719 | return -EBADMSG; |
1da177e4 | 2720 | } |
438d6c2c | 2721 | return 0; |
1da177e4 LT |
2722 | } |
2723 | ||
a1cdedac DB |
2724 | /** |
2725 | * i2c_smbus_read_byte - SMBus "receive byte" protocol | |
2726 | * @client: Handle to slave device | |
2727 | * | |
2728 | * This executes the SMBus "receive byte" protocol, returning negative errno | |
2729 | * else the byte received from the device. | |
2730 | */ | |
0cc43a18 | 2731 | s32 i2c_smbus_read_byte(const struct i2c_client *client) |
1da177e4 LT |
2732 | { |
2733 | union i2c_smbus_data data; | |
24a5bb7b DB |
2734 | int status; |
2735 | ||
2736 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2737 | I2C_SMBUS_READ, 0, | |
2738 | I2C_SMBUS_BYTE, &data); | |
2739 | return (status < 0) ? status : data.byte; | |
1da177e4 | 2740 | } |
c0564606 | 2741 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 | 2742 | |
a1cdedac DB |
2743 | /** |
2744 | * i2c_smbus_write_byte - SMBus "send byte" protocol | |
2745 | * @client: Handle to slave device | |
2746 | * @value: Byte to be sent | |
2747 | * | |
2748 | * This executes the SMBus "send byte" protocol, returning negative errno | |
2749 | * else zero on success. | |
2750 | */ | |
0cc43a18 | 2751 | s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) |
1da177e4 | 2752 | { |
7225acf4 | 2753 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
421ef47b | 2754 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 2755 | } |
c0564606 | 2756 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 | 2757 | |
a1cdedac DB |
2758 | /** |
2759 | * i2c_smbus_read_byte_data - SMBus "read byte" protocol | |
2760 | * @client: Handle to slave device | |
2761 | * @command: Byte interpreted by slave | |
2762 | * | |
2763 | * This executes the SMBus "read byte" protocol, returning negative errno | |
2764 | * else a data byte received from the device. | |
2765 | */ | |
0cc43a18 | 2766 | s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
2767 | { |
2768 | union i2c_smbus_data data; | |
24a5bb7b DB |
2769 | int status; |
2770 | ||
2771 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2772 | I2C_SMBUS_READ, command, | |
2773 | I2C_SMBUS_BYTE_DATA, &data); | |
2774 | return (status < 0) ? status : data.byte; | |
1da177e4 | 2775 | } |
c0564606 | 2776 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 | 2777 | |
a1cdedac DB |
2778 | /** |
2779 | * i2c_smbus_write_byte_data - SMBus "write byte" protocol | |
2780 | * @client: Handle to slave device | |
2781 | * @command: Byte interpreted by slave | |
2782 | * @value: Byte being written | |
2783 | * | |
2784 | * This executes the SMBus "write byte" protocol, returning negative errno | |
2785 | * else zero on success. | |
2786 | */ | |
0cc43a18 JD |
2787 | s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, |
2788 | u8 value) | |
1da177e4 LT |
2789 | { |
2790 | union i2c_smbus_data data; | |
2791 | data.byte = value; | |
7225acf4 FH |
2792 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2793 | I2C_SMBUS_WRITE, command, | |
2794 | I2C_SMBUS_BYTE_DATA, &data); | |
1da177e4 | 2795 | } |
c0564606 | 2796 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 | 2797 | |
a1cdedac DB |
2798 | /** |
2799 | * i2c_smbus_read_word_data - SMBus "read word" protocol | |
2800 | * @client: Handle to slave device | |
2801 | * @command: Byte interpreted by slave | |
2802 | * | |
2803 | * This executes the SMBus "read word" protocol, returning negative errno | |
2804 | * else a 16-bit unsigned "word" received from the device. | |
2805 | */ | |
0cc43a18 | 2806 | s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
2807 | { |
2808 | union i2c_smbus_data data; | |
24a5bb7b DB |
2809 | int status; |
2810 | ||
2811 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2812 | I2C_SMBUS_READ, command, | |
2813 | I2C_SMBUS_WORD_DATA, &data); | |
2814 | return (status < 0) ? status : data.word; | |
1da177e4 | 2815 | } |
c0564606 | 2816 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 | 2817 | |
a1cdedac DB |
2818 | /** |
2819 | * i2c_smbus_write_word_data - SMBus "write word" protocol | |
2820 | * @client: Handle to slave device | |
2821 | * @command: Byte interpreted by slave | |
2822 | * @value: 16-bit "word" being written | |
2823 | * | |
2824 | * This executes the SMBus "write word" protocol, returning negative errno | |
2825 | * else zero on success. | |
2826 | */ | |
0cc43a18 JD |
2827 | s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, |
2828 | u16 value) | |
1da177e4 LT |
2829 | { |
2830 | union i2c_smbus_data data; | |
2831 | data.word = value; | |
7225acf4 FH |
2832 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2833 | I2C_SMBUS_WRITE, command, | |
2834 | I2C_SMBUS_WORD_DATA, &data); | |
1da177e4 | 2835 | } |
c0564606 | 2836 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 2837 | |
a64ec07d | 2838 | /** |
a1cdedac | 2839 | * i2c_smbus_read_block_data - SMBus "block read" protocol |
a64ec07d | 2840 | * @client: Handle to slave device |
a1cdedac | 2841 | * @command: Byte interpreted by slave |
a64ec07d DB |
2842 | * @values: Byte array into which data will be read; big enough to hold |
2843 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
2844 | * | |
a1cdedac DB |
2845 | * This executes the SMBus "block read" protocol, returning negative errno |
2846 | * else the number of data bytes in the slave's response. | |
a64ec07d DB |
2847 | * |
2848 | * Note that using this function requires that the client's adapter support | |
2849 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
2850 | * support this; its emulation through I2C messaging relies on a specific | |
2851 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
2852 | */ | |
0cc43a18 | 2853 | s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, |
b86a1bc8 JD |
2854 | u8 *values) |
2855 | { | |
2856 | union i2c_smbus_data data; | |
24a5bb7b | 2857 | int status; |
b86a1bc8 | 2858 | |
24a5bb7b DB |
2859 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2860 | I2C_SMBUS_READ, command, | |
2861 | I2C_SMBUS_BLOCK_DATA, &data); | |
2862 | if (status) | |
2863 | return status; | |
b86a1bc8 JD |
2864 | |
2865 | memcpy(values, &data.block[1], data.block[0]); | |
2866 | return data.block[0]; | |
2867 | } | |
2868 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
2869 | ||
a1cdedac DB |
2870 | /** |
2871 | * i2c_smbus_write_block_data - SMBus "block write" protocol | |
2872 | * @client: Handle to slave device | |
2873 | * @command: Byte interpreted by slave | |
2874 | * @length: Size of data block; SMBus allows at most 32 bytes | |
2875 | * @values: Byte array which will be written. | |
2876 | * | |
2877 | * This executes the SMBus "block write" protocol, returning negative errno | |
2878 | * else zero on success. | |
2879 | */ | |
0cc43a18 | 2880 | s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 2881 | u8 length, const u8 *values) |
1da177e4 LT |
2882 | { |
2883 | union i2c_smbus_data data; | |
7656032b | 2884 | |
1da177e4 LT |
2885 | if (length > I2C_SMBUS_BLOCK_MAX) |
2886 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 2887 | data.block[0] = length; |
7656032b | 2888 | memcpy(&data.block[1], values, length); |
7225acf4 FH |
2889 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2890 | I2C_SMBUS_WRITE, command, | |
2891 | I2C_SMBUS_BLOCK_DATA, &data); | |
1da177e4 | 2892 | } |
c0564606 | 2893 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
2894 | |
2895 | /* Returns the number of read bytes */ | |
0cc43a18 | 2896 | s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, |
4b2643d7 | 2897 | u8 length, u8 *values) |
1da177e4 LT |
2898 | { |
2899 | union i2c_smbus_data data; | |
24a5bb7b | 2900 | int status; |
7656032b | 2901 | |
4b2643d7 JD |
2902 | if (length > I2C_SMBUS_BLOCK_MAX) |
2903 | length = I2C_SMBUS_BLOCK_MAX; | |
2904 | data.block[0] = length; | |
24a5bb7b DB |
2905 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2906 | I2C_SMBUS_READ, command, | |
2907 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
2908 | if (status < 0) | |
2909 | return status; | |
7656032b JD |
2910 | |
2911 | memcpy(values, &data.block[1], data.block[0]); | |
2912 | return data.block[0]; | |
1da177e4 | 2913 | } |
c0564606 | 2914 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 2915 | |
0cc43a18 | 2916 | s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 2917 | u8 length, const u8 *values) |
21bbd691 JD |
2918 | { |
2919 | union i2c_smbus_data data; | |
2920 | ||
2921 | if (length > I2C_SMBUS_BLOCK_MAX) | |
2922 | length = I2C_SMBUS_BLOCK_MAX; | |
2923 | data.block[0] = length; | |
2924 | memcpy(data.block + 1, values, length); | |
2925 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2926 | I2C_SMBUS_WRITE, command, | |
2927 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
2928 | } | |
c0564606 | 2929 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 2930 | |
438d6c2c | 2931 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 2932 | No checking of parameters is done! */ |
7225acf4 FH |
2933 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, |
2934 | unsigned short flags, | |
2935 | char read_write, u8 command, int size, | |
2936 | union i2c_smbus_data *data) | |
1da177e4 LT |
2937 | { |
2938 | /* So we need to generate a series of msgs. In the case of writing, we | |
2939 | need to use only one message; when reading, we need two. We initialize | |
2940 | most things with sane defaults, to keep the code below somewhat | |
2941 | simpler. */ | |
5c50d188 HI |
2942 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
2943 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
7225acf4 | 2944 | int num = read_write == I2C_SMBUS_READ ? 2 : 1; |
1da177e4 | 2945 | int i; |
421ef47b | 2946 | u8 partial_pec = 0; |
24a5bb7b | 2947 | int status; |
230da094 S |
2948 | struct i2c_msg msg[2] = { |
2949 | { | |
2950 | .addr = addr, | |
2951 | .flags = flags, | |
2952 | .len = 1, | |
2953 | .buf = msgbuf0, | |
2954 | }, { | |
2955 | .addr = addr, | |
2956 | .flags = flags | I2C_M_RD, | |
2957 | .len = 0, | |
2958 | .buf = msgbuf1, | |
2959 | }, | |
2960 | }; | |
1da177e4 LT |
2961 | |
2962 | msgbuf0[0] = command; | |
7225acf4 | 2963 | switch (size) { |
1da177e4 LT |
2964 | case I2C_SMBUS_QUICK: |
2965 | msg[0].len = 0; | |
2966 | /* Special case: The read/write field is used as data */ | |
f29d2e02 RK |
2967 | msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? |
2968 | I2C_M_RD : 0); | |
1da177e4 LT |
2969 | num = 1; |
2970 | break; | |
2971 | case I2C_SMBUS_BYTE: | |
2972 | if (read_write == I2C_SMBUS_READ) { | |
2973 | /* Special case: only a read! */ | |
2974 | msg[0].flags = I2C_M_RD | flags; | |
2975 | num = 1; | |
2976 | } | |
2977 | break; | |
2978 | case I2C_SMBUS_BYTE_DATA: | |
2979 | if (read_write == I2C_SMBUS_READ) | |
2980 | msg[1].len = 1; | |
2981 | else { | |
2982 | msg[0].len = 2; | |
2983 | msgbuf0[1] = data->byte; | |
2984 | } | |
2985 | break; | |
2986 | case I2C_SMBUS_WORD_DATA: | |
2987 | if (read_write == I2C_SMBUS_READ) | |
2988 | msg[1].len = 2; | |
2989 | else { | |
7225acf4 | 2990 | msg[0].len = 3; |
1da177e4 | 2991 | msgbuf0[1] = data->word & 0xff; |
7eff82c8 | 2992 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
2993 | } |
2994 | break; | |
2995 | case I2C_SMBUS_PROC_CALL: | |
2996 | num = 2; /* Special case */ | |
2997 | read_write = I2C_SMBUS_READ; | |
2998 | msg[0].len = 3; | |
2999 | msg[1].len = 2; | |
3000 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 3001 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
3002 | break; |
3003 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 3004 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
3005 | msg[1].flags |= I2C_M_RECV_LEN; |
3006 | msg[1].len = 1; /* block length will be added by | |
3007 | the underlying bus driver */ | |
1da177e4 LT |
3008 | } else { |
3009 | msg[0].len = data->block[0] + 2; | |
3010 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
24a5bb7b DB |
3011 | dev_err(&adapter->dev, |
3012 | "Invalid block write size %d\n", | |
3013 | data->block[0]); | |
3014 | return -EINVAL; | |
1da177e4 | 3015 | } |
5c50d188 | 3016 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
3017 | msgbuf0[i] = data->block[i-1]; |
3018 | } | |
3019 | break; | |
3020 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
3021 | num = 2; /* Another special case */ |
3022 | read_write = I2C_SMBUS_READ; | |
3023 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
24a5bb7b DB |
3024 | dev_err(&adapter->dev, |
3025 | "Invalid block write size %d\n", | |
209d27c3 | 3026 | data->block[0]); |
24a5bb7b | 3027 | return -EINVAL; |
209d27c3 JD |
3028 | } |
3029 | msg[0].len = data->block[0] + 2; | |
3030 | for (i = 1; i < msg[0].len; i++) | |
3031 | msgbuf0[i] = data->block[i-1]; | |
3032 | msg[1].flags |= I2C_M_RECV_LEN; | |
3033 | msg[1].len = 1; /* block length will be added by | |
3034 | the underlying bus driver */ | |
3035 | break; | |
1da177e4 LT |
3036 | case I2C_SMBUS_I2C_BLOCK_DATA: |
3037 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 3038 | msg[1].len = data->block[0]; |
1da177e4 LT |
3039 | } else { |
3040 | msg[0].len = data->block[0] + 1; | |
30dac746 | 3041 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
24a5bb7b DB |
3042 | dev_err(&adapter->dev, |
3043 | "Invalid block write size %d\n", | |
3044 | data->block[0]); | |
3045 | return -EINVAL; | |
1da177e4 LT |
3046 | } |
3047 | for (i = 1; i <= data->block[0]; i++) | |
3048 | msgbuf0[i] = data->block[i]; | |
3049 | } | |
3050 | break; | |
3051 | default: | |
24a5bb7b DB |
3052 | dev_err(&adapter->dev, "Unsupported transaction %d\n", size); |
3053 | return -EOPNOTSUPP; | |
1da177e4 LT |
3054 | } |
3055 | ||
421ef47b JD |
3056 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
3057 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
3058 | if (i) { | |
3059 | /* Compute PEC if first message is a write */ | |
3060 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 3061 | if (num == 1) /* Write only */ |
421ef47b JD |
3062 | i2c_smbus_add_pec(&msg[0]); |
3063 | else /* Write followed by read */ | |
3064 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
3065 | } | |
3066 | /* Ask for PEC if last message is a read */ | |
3067 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 3068 | msg[num-1].len++; |
421ef47b JD |
3069 | } |
3070 | ||
24a5bb7b DB |
3071 | status = i2c_transfer(adapter, msg, num); |
3072 | if (status < 0) | |
3073 | return status; | |
1da177e4 | 3074 | |
421ef47b JD |
3075 | /* Check PEC if last message is a read */ |
3076 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
24a5bb7b DB |
3077 | status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); |
3078 | if (status < 0) | |
3079 | return status; | |
421ef47b JD |
3080 | } |
3081 | ||
1da177e4 | 3082 | if (read_write == I2C_SMBUS_READ) |
7225acf4 FH |
3083 | switch (size) { |
3084 | case I2C_SMBUS_BYTE: | |
3085 | data->byte = msgbuf0[0]; | |
3086 | break; | |
3087 | case I2C_SMBUS_BYTE_DATA: | |
3088 | data->byte = msgbuf1[0]; | |
3089 | break; | |
3090 | case I2C_SMBUS_WORD_DATA: | |
3091 | case I2C_SMBUS_PROC_CALL: | |
3092 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
3093 | break; | |
3094 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
3095 | for (i = 0; i < data->block[0]; i++) | |
3096 | data->block[i+1] = msgbuf1[i]; | |
3097 | break; | |
3098 | case I2C_SMBUS_BLOCK_DATA: | |
3099 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
3100 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
3101 | data->block[i] = msgbuf1[i]; | |
3102 | break; | |
1da177e4 LT |
3103 | } |
3104 | return 0; | |
3105 | } | |
3106 | ||
a1cdedac DB |
3107 | /** |
3108 | * i2c_smbus_xfer - execute SMBus protocol operations | |
3109 | * @adapter: Handle to I2C bus | |
3110 | * @addr: Address of SMBus slave on that bus | |
3111 | * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) | |
3112 | * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE | |
3113 | * @command: Byte interpreted by slave, for protocols which use such bytes | |
3114 | * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL | |
3115 | * @data: Data to be read or written | |
3116 | * | |
3117 | * This executes an SMBus protocol operation, and returns a negative | |
3118 | * errno code else zero on success. | |
3119 | */ | |
09b8ce0a | 3120 | s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, |
a1cdedac | 3121 | char read_write, u8 command, int protocol, |
09b8ce0a | 3122 | union i2c_smbus_data *data) |
1da177e4 | 3123 | { |
66b650f0 CW |
3124 | unsigned long orig_jiffies; |
3125 | int try; | |
1da177e4 | 3126 | s32 res; |
1da177e4 | 3127 | |
8a325997 DH |
3128 | /* If enabled, the following two tracepoints are conditional on |
3129 | * read_write and protocol. | |
3130 | */ | |
3131 | trace_smbus_write(adapter, addr, flags, read_write, | |
3132 | command, protocol, data); | |
3133 | trace_smbus_read(adapter, addr, flags, read_write, | |
3134 | command, protocol); | |
3135 | ||
d47726c5 | 3136 | flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB; |
1da177e4 LT |
3137 | |
3138 | if (adapter->algo->smbus_xfer) { | |
8320f495 | 3139 | i2c_lock_bus(adapter, I2C_LOCK_SEGMENT); |
66b650f0 CW |
3140 | |
3141 | /* Retry automatically on arbitration loss */ | |
3142 | orig_jiffies = jiffies; | |
3143 | for (res = 0, try = 0; try <= adapter->retries; try++) { | |
3144 | res = adapter->algo->smbus_xfer(adapter, addr, flags, | |
3145 | read_write, command, | |
3146 | protocol, data); | |
3147 | if (res != -EAGAIN) | |
3148 | break; | |
3149 | if (time_after(jiffies, | |
3150 | orig_jiffies + adapter->timeout)) | |
3151 | break; | |
3152 | } | |
8320f495 | 3153 | i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT); |
1da177e4 | 3154 | |
72fc2c7f | 3155 | if (res != -EOPNOTSUPP || !adapter->algo->master_xfer) |
8a325997 | 3156 | goto trace; |
72fc2c7f LP |
3157 | /* |
3158 | * Fall back to i2c_smbus_xfer_emulated if the adapter doesn't | |
3159 | * implement native support for the SMBus operation. | |
3160 | */ | |
3161 | } | |
3162 | ||
8a325997 DH |
3163 | res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, |
3164 | command, protocol, data); | |
3165 | ||
3166 | trace: | |
3167 | /* If enabled, the reply tracepoint is conditional on read_write. */ | |
3168 | trace_smbus_reply(adapter, addr, flags, read_write, | |
3169 | command, protocol, data); | |
3170 | trace_smbus_result(adapter, addr, flags, read_write, | |
3171 | command, protocol, res); | |
3172 | ||
3173 | return res; | |
1da177e4 | 3174 | } |
1da177e4 | 3175 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 | 3176 | |
01eef96e IT |
3177 | /** |
3178 | * i2c_smbus_read_i2c_block_data_or_emulated - read block or emulate | |
3179 | * @client: Handle to slave device | |
3180 | * @command: Byte interpreted by slave | |
3181 | * @length: Size of data block; SMBus allows at most I2C_SMBUS_BLOCK_MAX bytes | |
3182 | * @values: Byte array into which data will be read; big enough to hold | |
3183 | * the data returned by the slave. SMBus allows at most | |
3184 | * I2C_SMBUS_BLOCK_MAX bytes. | |
3185 | * | |
3186 | * This executes the SMBus "block read" protocol if supported by the adapter. | |
3187 | * If block read is not supported, it emulates it using either word or byte | |
3188 | * read protocols depending on availability. | |
3189 | * | |
3190 | * The addresses of the I2C slave device that are accessed with this function | |
3191 | * must be mapped to a linear region, so that a block read will have the same | |
3192 | * effect as a byte read. Before using this function you must double-check | |
3193 | * if the I2C slave does support exchanging a block transfer with a byte | |
3194 | * transfer. | |
3195 | */ | |
3196 | s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, | |
3197 | u8 command, u8 length, u8 *values) | |
3198 | { | |
3199 | u8 i = 0; | |
3200 | int status; | |
3201 | ||
3202 | if (length > I2C_SMBUS_BLOCK_MAX) | |
3203 | length = I2C_SMBUS_BLOCK_MAX; | |
3204 | ||
3205 | if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) | |
3206 | return i2c_smbus_read_i2c_block_data(client, command, length, values); | |
3207 | ||
3208 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
3209 | return -EOPNOTSUPP; | |
3210 | ||
3211 | if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)) { | |
3212 | while ((i + 2) <= length) { | |
3213 | status = i2c_smbus_read_word_data(client, command + i); | |
3214 | if (status < 0) | |
3215 | return status; | |
3216 | values[i] = status & 0xff; | |
3217 | values[i + 1] = status >> 8; | |
3218 | i += 2; | |
3219 | } | |
3220 | } | |
3221 | ||
3222 | while (i < length) { | |
3223 | status = i2c_smbus_read_byte_data(client, command + i); | |
3224 | if (status < 0) | |
3225 | return status; | |
3226 | values[i] = status; | |
3227 | i++; | |
3228 | } | |
3229 | ||
3230 | return i; | |
3231 | } | |
3232 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data_or_emulated); | |
3233 | ||
d5fd120e | 3234 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 WS |
3235 | int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb) |
3236 | { | |
3237 | int ret; | |
3238 | ||
0c7cab96 WS |
3239 | if (!client || !slave_cb) { |
3240 | WARN(1, "insufficent data\n"); | |
4b1acc43 | 3241 | return -EINVAL; |
0c7cab96 | 3242 | } |
4b1acc43 | 3243 | |
c6909d6f WS |
3244 | if (!(client->flags & I2C_CLIENT_SLAVE)) |
3245 | dev_warn(&client->dev, "%s: client slave flag not set. You might see address collisions\n", | |
3246 | __func__); | |
3247 | ||
4b1acc43 WS |
3248 | if (!(client->flags & I2C_CLIENT_TEN)) { |
3249 | /* Enforce stricter address checking */ | |
66be6056 | 3250 | ret = i2c_check_7bit_addr_validity_strict(client->addr); |
0c7cab96 WS |
3251 | if (ret) { |
3252 | dev_err(&client->dev, "%s: invalid address\n", __func__); | |
4b1acc43 | 3253 | return ret; |
0c7cab96 | 3254 | } |
4b1acc43 WS |
3255 | } |
3256 | ||
0c7cab96 WS |
3257 | if (!client->adapter->algo->reg_slave) { |
3258 | dev_err(&client->dev, "%s: not supported by adapter\n", __func__); | |
4b1acc43 | 3259 | return -EOPNOTSUPP; |
0c7cab96 | 3260 | } |
4b1acc43 WS |
3261 | |
3262 | client->slave_cb = slave_cb; | |
3263 | ||
3264 | i2c_lock_adapter(client->adapter); | |
3265 | ret = client->adapter->algo->reg_slave(client); | |
3266 | i2c_unlock_adapter(client->adapter); | |
3267 | ||
0c7cab96 | 3268 | if (ret) { |
4b1acc43 | 3269 | client->slave_cb = NULL; |
0c7cab96 WS |
3270 | dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret); |
3271 | } | |
4b1acc43 WS |
3272 | |
3273 | return ret; | |
3274 | } | |
3275 | EXPORT_SYMBOL_GPL(i2c_slave_register); | |
3276 | ||
3277 | int i2c_slave_unregister(struct i2c_client *client) | |
3278 | { | |
3279 | int ret; | |
3280 | ||
0c7cab96 WS |
3281 | if (!client->adapter->algo->unreg_slave) { |
3282 | dev_err(&client->dev, "%s: not supported by adapter\n", __func__); | |
4b1acc43 | 3283 | return -EOPNOTSUPP; |
0c7cab96 | 3284 | } |
4b1acc43 WS |
3285 | |
3286 | i2c_lock_adapter(client->adapter); | |
3287 | ret = client->adapter->algo->unreg_slave(client); | |
3288 | i2c_unlock_adapter(client->adapter); | |
3289 | ||
3290 | if (ret == 0) | |
3291 | client->slave_cb = NULL; | |
0c7cab96 WS |
3292 | else |
3293 | dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret); | |
4b1acc43 WS |
3294 | |
3295 | return ret; | |
3296 | } | |
3297 | EXPORT_SYMBOL_GPL(i2c_slave_unregister); | |
d5fd120e | 3298 | #endif |
4b1acc43 | 3299 | |
1da177e4 LT |
3300 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); |
3301 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
3302 | MODULE_LICENSE("GPL"); |