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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 | |
13 | GNU General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU General Public License | |
16 | along with this program; if not, write to the Free Software | |
17 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
18 | /* ------------------------------------------------------------------------- */ | |
19 | ||
96de0e25 | 20 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. |
1da177e4 | 21 | All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> |
421ef47b | 22 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
0826374b ML |
23 | Jean Delvare <khali@linux-fr.org> |
24 | Mux support by Rodolfo Giometti <giometti@enneenne.com> and | |
25 | Michael Lawnick <michael.lawnick.ext@nsn.com> */ | |
1da177e4 | 26 | |
1da177e4 LT |
27 | #include <linux/module.h> |
28 | #include <linux/kernel.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/slab.h> | |
31 | #include <linux/i2c.h> | |
32 | #include <linux/init.h> | |
33 | #include <linux/idr.h> | |
b3585e4f | 34 | #include <linux/mutex.h> |
959e85f7 | 35 | #include <linux/of_device.h> |
b8d6f45b | 36 | #include <linux/completion.h> |
cea443a8 MR |
37 | #include <linux/hardirq.h> |
38 | #include <linux/irqflags.h> | |
f18c41da | 39 | #include <linux/rwsem.h> |
6de468ae | 40 | #include <linux/pm_runtime.h> |
1da177e4 LT |
41 | #include <asm/uaccess.h> |
42 | ||
9c1600ed DB |
43 | #include "i2c-core.h" |
44 | ||
1da177e4 | 45 | |
6629dcff | 46 | /* core_lock protects i2c_adapter_idr, and guarantees |
35fc37f8 JD |
47 | that device detection, deletion of detected devices, and attach_adapter |
48 | and detach_adapter calls are serialized */ | |
caada32a | 49 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
50 | static DEFINE_IDR(i2c_adapter_idr); |
51 | ||
4f8cf824 | 52 | static struct device_type i2c_client_type; |
4735c98f | 53 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
f37dd80a DB |
54 | |
55 | /* ------------------------------------------------------------------------- */ | |
56 | ||
d2653e92 JD |
57 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
58 | const struct i2c_client *client) | |
59 | { | |
60 | while (id->name[0]) { | |
61 | if (strcmp(client->name, id->name) == 0) | |
62 | return id; | |
63 | id++; | |
64 | } | |
65 | return NULL; | |
66 | } | |
67 | ||
1da177e4 LT |
68 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
69 | { | |
51298d12 JD |
70 | struct i2c_client *client = i2c_verify_client(dev); |
71 | struct i2c_driver *driver; | |
72 | ||
73 | if (!client) | |
74 | return 0; | |
7b4fbc50 | 75 | |
959e85f7 GL |
76 | /* Attempt an OF style match */ |
77 | if (of_driver_match_device(dev, drv)) | |
78 | return 1; | |
79 | ||
51298d12 | 80 | driver = to_i2c_driver(drv); |
d2653e92 JD |
81 | /* match on an id table if there is one */ |
82 | if (driver->id_table) | |
83 | return i2c_match_id(driver->id_table, client) != NULL; | |
84 | ||
eb8a7908 | 85 | return 0; |
1da177e4 LT |
86 | } |
87 | ||
7b4fbc50 DB |
88 | #ifdef CONFIG_HOTPLUG |
89 | ||
90 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 91 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
92 | { |
93 | struct i2c_client *client = to_i2c_client(dev); | |
7b4fbc50 | 94 | |
eb8a7908 JD |
95 | if (add_uevent_var(env, "MODALIAS=%s%s", |
96 | I2C_MODULE_PREFIX, client->name)) | |
97 | return -ENOMEM; | |
7b4fbc50 DB |
98 | dev_dbg(dev, "uevent\n"); |
99 | return 0; | |
100 | } | |
101 | ||
102 | #else | |
103 | #define i2c_device_uevent NULL | |
104 | #endif /* CONFIG_HOTPLUG */ | |
105 | ||
f37dd80a | 106 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 107 | { |
51298d12 JD |
108 | struct i2c_client *client = i2c_verify_client(dev); |
109 | struct i2c_driver *driver; | |
50c3304a | 110 | int status; |
7b4fbc50 | 111 | |
51298d12 JD |
112 | if (!client) |
113 | return 0; | |
114 | ||
115 | driver = to_i2c_driver(dev->driver); | |
e0457442 | 116 | if (!driver->probe || !driver->id_table) |
7b4fbc50 DB |
117 | return -ENODEV; |
118 | client->driver = driver; | |
ee35425c MP |
119 | if (!device_can_wakeup(&client->dev)) |
120 | device_init_wakeup(&client->dev, | |
121 | client->flags & I2C_CLIENT_WAKE); | |
7b4fbc50 | 122 | dev_dbg(dev, "probe\n"); |
d2653e92 | 123 | |
e0457442 | 124 | status = driver->probe(client, i2c_match_id(driver->id_table, client)); |
e4a7b9b0 | 125 | if (status) { |
50c3304a | 126 | client->driver = NULL; |
e4a7b9b0 WS |
127 | i2c_set_clientdata(client, NULL); |
128 | } | |
50c3304a | 129 | return status; |
f37dd80a | 130 | } |
1da177e4 | 131 | |
f37dd80a DB |
132 | static int i2c_device_remove(struct device *dev) |
133 | { | |
51298d12 | 134 | struct i2c_client *client = i2c_verify_client(dev); |
a1d9e6e4 DB |
135 | struct i2c_driver *driver; |
136 | int status; | |
137 | ||
51298d12 | 138 | if (!client || !dev->driver) |
a1d9e6e4 DB |
139 | return 0; |
140 | ||
141 | driver = to_i2c_driver(dev->driver); | |
142 | if (driver->remove) { | |
143 | dev_dbg(dev, "remove\n"); | |
144 | status = driver->remove(client); | |
145 | } else { | |
146 | dev->driver = NULL; | |
147 | status = 0; | |
148 | } | |
e4a7b9b0 | 149 | if (status == 0) { |
a1d9e6e4 | 150 | client->driver = NULL; |
e4a7b9b0 WS |
151 | i2c_set_clientdata(client, NULL); |
152 | } | |
a1d9e6e4 | 153 | return status; |
1da177e4 LT |
154 | } |
155 | ||
f37dd80a | 156 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 157 | { |
51298d12 | 158 | struct i2c_client *client = i2c_verify_client(dev); |
f37dd80a DB |
159 | struct i2c_driver *driver; |
160 | ||
51298d12 | 161 | if (!client || !dev->driver) |
f37dd80a DB |
162 | return; |
163 | driver = to_i2c_driver(dev->driver); | |
164 | if (driver->shutdown) | |
51298d12 | 165 | driver->shutdown(client); |
1da177e4 LT |
166 | } |
167 | ||
2f60ba70 RW |
168 | #ifdef CONFIG_PM_SLEEP |
169 | static int i2c_legacy_suspend(struct device *dev, pm_message_t mesg) | |
54067ee2 | 170 | { |
2f60ba70 RW |
171 | struct i2c_client *client = i2c_verify_client(dev); |
172 | struct i2c_driver *driver; | |
54067ee2 | 173 | |
2f60ba70 | 174 | if (!client || !dev->driver) |
54067ee2 | 175 | return 0; |
2f60ba70 RW |
176 | driver = to_i2c_driver(dev->driver); |
177 | if (!driver->suspend) | |
54067ee2 | 178 | return 0; |
2f60ba70 | 179 | return driver->suspend(client, mesg); |
54067ee2 | 180 | } |
181 | ||
2f60ba70 | 182 | static int i2c_legacy_resume(struct device *dev) |
54067ee2 | 183 | { |
2f60ba70 RW |
184 | struct i2c_client *client = i2c_verify_client(dev); |
185 | struct i2c_driver *driver; | |
54067ee2 | 186 | |
2f60ba70 | 187 | if (!client || !dev->driver) |
54067ee2 | 188 | return 0; |
2f60ba70 RW |
189 | driver = to_i2c_driver(dev->driver); |
190 | if (!driver->resume) | |
54067ee2 | 191 | return 0; |
2f60ba70 | 192 | return driver->resume(client); |
54067ee2 | 193 | } |
54067ee2 | 194 | |
2f60ba70 | 195 | static int i2c_device_pm_suspend(struct device *dev) |
6de468ae | 196 | { |
2f60ba70 | 197 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
6de468ae | 198 | |
d529de29 MB |
199 | if (pm) |
200 | return pm_generic_suspend(dev); | |
201 | else | |
202 | return i2c_legacy_suspend(dev, PMSG_SUSPEND); | |
6de468ae MB |
203 | } |
204 | ||
2f60ba70 | 205 | static int i2c_device_pm_resume(struct device *dev) |
6de468ae | 206 | { |
2f60ba70 | 207 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
6de468ae | 208 | |
2f60ba70 | 209 | if (pm) |
d529de29 | 210 | return pm_generic_resume(dev); |
2f60ba70 | 211 | else |
d529de29 | 212 | return i2c_legacy_resume(dev); |
6de468ae | 213 | } |
6de468ae | 214 | |
2f60ba70 | 215 | static int i2c_device_pm_freeze(struct device *dev) |
1da177e4 | 216 | { |
2f60ba70 | 217 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
f37dd80a | 218 | |
d529de29 MB |
219 | if (pm) |
220 | return pm_generic_freeze(dev); | |
221 | else | |
222 | return i2c_legacy_suspend(dev, PMSG_FREEZE); | |
1da177e4 LT |
223 | } |
224 | ||
2f60ba70 | 225 | static int i2c_device_pm_thaw(struct device *dev) |
1da177e4 | 226 | { |
2f60ba70 | 227 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
f37dd80a | 228 | |
d529de29 MB |
229 | if (pm) |
230 | return pm_generic_thaw(dev); | |
231 | else | |
232 | return i2c_legacy_resume(dev); | |
2f60ba70 RW |
233 | } |
234 | ||
235 | static int i2c_device_pm_poweroff(struct device *dev) | |
236 | { | |
237 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; | |
238 | ||
d529de29 MB |
239 | if (pm) |
240 | return pm_generic_poweroff(dev); | |
241 | else | |
242 | return i2c_legacy_suspend(dev, PMSG_HIBERNATE); | |
2f60ba70 RW |
243 | } |
244 | ||
245 | static int i2c_device_pm_restore(struct device *dev) | |
246 | { | |
247 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; | |
2f60ba70 RW |
248 | |
249 | if (pm) | |
d529de29 | 250 | return pm_generic_restore(dev); |
2f60ba70 | 251 | else |
d529de29 | 252 | return i2c_legacy_resume(dev); |
1da177e4 | 253 | } |
2f60ba70 RW |
254 | #else /* !CONFIG_PM_SLEEP */ |
255 | #define i2c_device_pm_suspend NULL | |
256 | #define i2c_device_pm_resume NULL | |
257 | #define i2c_device_pm_freeze NULL | |
258 | #define i2c_device_pm_thaw NULL | |
259 | #define i2c_device_pm_poweroff NULL | |
260 | #define i2c_device_pm_restore NULL | |
261 | #endif /* !CONFIG_PM_SLEEP */ | |
1da177e4 | 262 | |
9c1600ed DB |
263 | static void i2c_client_dev_release(struct device *dev) |
264 | { | |
265 | kfree(to_i2c_client(dev)); | |
266 | } | |
267 | ||
09b8ce0a | 268 | static ssize_t |
4f8cf824 | 269 | show_name(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 | 270 | { |
4f8cf824 JD |
271 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
272 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); | |
7b4fbc50 DB |
273 | } |
274 | ||
09b8ce0a ZX |
275 | static ssize_t |
276 | show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
7b4fbc50 DB |
277 | { |
278 | struct i2c_client *client = to_i2c_client(dev); | |
eb8a7908 | 279 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 DB |
280 | } |
281 | ||
4f8cf824 | 282 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); |
51298d12 JD |
283 | static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); |
284 | ||
285 | static struct attribute *i2c_dev_attrs[] = { | |
286 | &dev_attr_name.attr, | |
7b4fbc50 | 287 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
51298d12 JD |
288 | &dev_attr_modalias.attr, |
289 | NULL | |
290 | }; | |
291 | ||
292 | static struct attribute_group i2c_dev_attr_group = { | |
293 | .attrs = i2c_dev_attrs, | |
294 | }; | |
295 | ||
296 | static const struct attribute_group *i2c_dev_attr_groups[] = { | |
297 | &i2c_dev_attr_group, | |
298 | NULL | |
7b4fbc50 DB |
299 | }; |
300 | ||
0b2c3688 | 301 | static const struct dev_pm_ops i2c_device_pm_ops = { |
54067ee2 | 302 | .suspend = i2c_device_pm_suspend, |
303 | .resume = i2c_device_pm_resume, | |
2f60ba70 RW |
304 | .freeze = i2c_device_pm_freeze, |
305 | .thaw = i2c_device_pm_thaw, | |
306 | .poweroff = i2c_device_pm_poweroff, | |
307 | .restore = i2c_device_pm_restore, | |
308 | SET_RUNTIME_PM_OPS( | |
309 | pm_generic_runtime_suspend, | |
310 | pm_generic_runtime_resume, | |
311 | pm_generic_runtime_idle | |
312 | ) | |
54067ee2 | 313 | }; |
314 | ||
e9ca9eb9 | 315 | struct bus_type i2c_bus_type = { |
f37dd80a DB |
316 | .name = "i2c", |
317 | .match = i2c_device_match, | |
318 | .probe = i2c_device_probe, | |
319 | .remove = i2c_device_remove, | |
320 | .shutdown = i2c_device_shutdown, | |
54067ee2 | 321 | .pm = &i2c_device_pm_ops, |
b864c7d5 | 322 | }; |
e9ca9eb9 | 323 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
b864c7d5 | 324 | |
51298d12 JD |
325 | static struct device_type i2c_client_type = { |
326 | .groups = i2c_dev_attr_groups, | |
327 | .uevent = i2c_device_uevent, | |
328 | .release = i2c_client_dev_release, | |
329 | }; | |
330 | ||
9b766b81 DB |
331 | |
332 | /** | |
333 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
334 | * @dev: device, probably from some driver model iterator | |
335 | * | |
336 | * When traversing the driver model tree, perhaps using driver model | |
337 | * iterators like @device_for_each_child(), you can't assume very much | |
338 | * about the nodes you find. Use this function to avoid oopses caused | |
339 | * by wrongly treating some non-I2C device as an i2c_client. | |
340 | */ | |
341 | struct i2c_client *i2c_verify_client(struct device *dev) | |
342 | { | |
51298d12 | 343 | return (dev->type == &i2c_client_type) |
9b766b81 DB |
344 | ? to_i2c_client(dev) |
345 | : NULL; | |
346 | } | |
347 | EXPORT_SYMBOL(i2c_verify_client); | |
348 | ||
349 | ||
3a89db5f JD |
350 | /* This is a permissive address validity check, I2C address map constraints |
351 | * are purposedly not enforced, except for the general call address. */ | |
352 | static int i2c_check_client_addr_validity(const struct i2c_client *client) | |
353 | { | |
354 | if (client->flags & I2C_CLIENT_TEN) { | |
355 | /* 10-bit address, all values are valid */ | |
356 | if (client->addr > 0x3ff) | |
357 | return -EINVAL; | |
358 | } else { | |
359 | /* 7-bit address, reject the general call address */ | |
360 | if (client->addr == 0x00 || client->addr > 0x7f) | |
361 | return -EINVAL; | |
362 | } | |
363 | return 0; | |
364 | } | |
365 | ||
656b8761 JD |
366 | /* And this is a strict address validity check, used when probing. If a |
367 | * device uses a reserved address, then it shouldn't be probed. 7-bit | |
368 | * addressing is assumed, 10-bit address devices are rare and should be | |
369 | * explicitly enumerated. */ | |
370 | static int i2c_check_addr_validity(unsigned short addr) | |
371 | { | |
372 | /* | |
373 | * Reserved addresses per I2C specification: | |
374 | * 0x00 General call address / START byte | |
375 | * 0x01 CBUS address | |
376 | * 0x02 Reserved for different bus format | |
377 | * 0x03 Reserved for future purposes | |
378 | * 0x04-0x07 Hs-mode master code | |
379 | * 0x78-0x7b 10-bit slave addressing | |
380 | * 0x7c-0x7f Reserved for future purposes | |
381 | */ | |
382 | if (addr < 0x08 || addr > 0x77) | |
383 | return -EINVAL; | |
384 | return 0; | |
385 | } | |
386 | ||
3b5f794b JD |
387 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
388 | { | |
389 | struct i2c_client *client = i2c_verify_client(dev); | |
390 | int addr = *(int *)addrp; | |
391 | ||
392 | if (client && client->addr == addr) | |
393 | return -EBUSY; | |
394 | return 0; | |
395 | } | |
396 | ||
0826374b ML |
397 | /* walk up mux tree */ |
398 | static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) | |
399 | { | |
97cc4d49 | 400 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
401 | int result; |
402 | ||
403 | result = device_for_each_child(&adapter->dev, &addr, | |
404 | __i2c_check_addr_busy); | |
405 | ||
97cc4d49 JD |
406 | if (!result && parent) |
407 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
408 | |
409 | return result; | |
410 | } | |
411 | ||
412 | /* recurse down mux tree */ | |
413 | static int i2c_check_mux_children(struct device *dev, void *addrp) | |
414 | { | |
415 | int result; | |
416 | ||
417 | if (dev->type == &i2c_adapter_type) | |
418 | result = device_for_each_child(dev, addrp, | |
419 | i2c_check_mux_children); | |
420 | else | |
421 | result = __i2c_check_addr_busy(dev, addrp); | |
422 | ||
423 | return result; | |
424 | } | |
425 | ||
3b5f794b JD |
426 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) |
427 | { | |
97cc4d49 | 428 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
429 | int result = 0; |
430 | ||
97cc4d49 JD |
431 | if (parent) |
432 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
433 | |
434 | if (!result) | |
435 | result = device_for_each_child(&adapter->dev, &addr, | |
436 | i2c_check_mux_children); | |
437 | ||
438 | return result; | |
3b5f794b JD |
439 | } |
440 | ||
fe61e07e JD |
441 | /** |
442 | * i2c_lock_adapter - Get exclusive access to an I2C bus segment | |
443 | * @adapter: Target I2C bus segment | |
444 | */ | |
445 | void i2c_lock_adapter(struct i2c_adapter *adapter) | |
446 | { | |
97cc4d49 JD |
447 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
448 | ||
449 | if (parent) | |
450 | i2c_lock_adapter(parent); | |
0826374b ML |
451 | else |
452 | rt_mutex_lock(&adapter->bus_lock); | |
fe61e07e JD |
453 | } |
454 | EXPORT_SYMBOL_GPL(i2c_lock_adapter); | |
455 | ||
456 | /** | |
457 | * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment | |
458 | * @adapter: Target I2C bus segment | |
459 | */ | |
460 | static int i2c_trylock_adapter(struct i2c_adapter *adapter) | |
461 | { | |
97cc4d49 JD |
462 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
463 | ||
464 | if (parent) | |
465 | return i2c_trylock_adapter(parent); | |
0826374b ML |
466 | else |
467 | return rt_mutex_trylock(&adapter->bus_lock); | |
fe61e07e JD |
468 | } |
469 | ||
470 | /** | |
471 | * i2c_unlock_adapter - Release exclusive access to an I2C bus segment | |
472 | * @adapter: Target I2C bus segment | |
473 | */ | |
474 | void i2c_unlock_adapter(struct i2c_adapter *adapter) | |
475 | { | |
97cc4d49 JD |
476 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
477 | ||
478 | if (parent) | |
479 | i2c_unlock_adapter(parent); | |
0826374b ML |
480 | else |
481 | rt_mutex_unlock(&adapter->bus_lock); | |
fe61e07e JD |
482 | } |
483 | EXPORT_SYMBOL_GPL(i2c_unlock_adapter); | |
484 | ||
9c1600ed | 485 | /** |
f8a227e8 | 486 | * i2c_new_device - instantiate an i2c device |
9c1600ed DB |
487 | * @adap: the adapter managing the device |
488 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 489 | * Context: can sleep |
9c1600ed | 490 | * |
f8a227e8 JD |
491 | * Create an i2c device. Binding is handled through driver model |
492 | * probe()/remove() methods. A driver may be bound to this device when we | |
493 | * return from this function, or any later moment (e.g. maybe hotplugging will | |
494 | * load the driver module). This call is not appropriate for use by mainboard | |
495 | * initialization logic, which usually runs during an arch_initcall() long | |
496 | * before any i2c_adapter could exist. | |
9c1600ed DB |
497 | * |
498 | * This returns the new i2c client, which may be saved for later use with | |
499 | * i2c_unregister_device(); or NULL to indicate an error. | |
500 | */ | |
501 | struct i2c_client * | |
502 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
503 | { | |
504 | struct i2c_client *client; | |
505 | int status; | |
506 | ||
507 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
508 | if (!client) | |
509 | return NULL; | |
510 | ||
511 | client->adapter = adap; | |
512 | ||
513 | client->dev.platform_data = info->platform_data; | |
3bbb835d | 514 | |
11f1f2af AV |
515 | if (info->archdata) |
516 | client->dev.archdata = *info->archdata; | |
517 | ||
ee35425c | 518 | client->flags = info->flags; |
9c1600ed DB |
519 | client->addr = info->addr; |
520 | client->irq = info->irq; | |
521 | ||
9c1600ed DB |
522 | strlcpy(client->name, info->type, sizeof(client->name)); |
523 | ||
3a89db5f JD |
524 | /* Check for address validity */ |
525 | status = i2c_check_client_addr_validity(client); | |
526 | if (status) { | |
527 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", | |
528 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); | |
529 | goto out_err_silent; | |
530 | } | |
531 | ||
f8a227e8 | 532 | /* Check for address business */ |
3b5f794b | 533 | status = i2c_check_addr_busy(adap, client->addr); |
f8a227e8 JD |
534 | if (status) |
535 | goto out_err; | |
536 | ||
537 | client->dev.parent = &client->adapter->dev; | |
538 | client->dev.bus = &i2c_bus_type; | |
51298d12 | 539 | client->dev.type = &i2c_client_type; |
d12d42f7 GL |
540 | #ifdef CONFIG_OF |
541 | client->dev.of_node = info->of_node; | |
542 | #endif | |
f8a227e8 JD |
543 | |
544 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), | |
545 | client->addr); | |
546 | status = device_register(&client->dev); | |
547 | if (status) | |
548 | goto out_err; | |
549 | ||
f8a227e8 JD |
550 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
551 | client->name, dev_name(&client->dev)); | |
552 | ||
9c1600ed | 553 | return client; |
f8a227e8 JD |
554 | |
555 | out_err: | |
556 | dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x " | |
557 | "(%d)\n", client->name, client->addr, status); | |
3a89db5f | 558 | out_err_silent: |
f8a227e8 JD |
559 | kfree(client); |
560 | return NULL; | |
9c1600ed DB |
561 | } |
562 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
563 | ||
564 | ||
565 | /** | |
566 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
567 | * @client: value returned from i2c_new_device() | |
d64f73be | 568 | * Context: can sleep |
9c1600ed DB |
569 | */ |
570 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 | 571 | { |
a1d9e6e4 DB |
572 | device_unregister(&client->dev); |
573 | } | |
9c1600ed | 574 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
575 | |
576 | ||
60b129d7 JD |
577 | static const struct i2c_device_id dummy_id[] = { |
578 | { "dummy", 0 }, | |
579 | { }, | |
580 | }; | |
581 | ||
d2653e92 JD |
582 | static int dummy_probe(struct i2c_client *client, |
583 | const struct i2c_device_id *id) | |
584 | { | |
585 | return 0; | |
586 | } | |
587 | ||
588 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
589 | { |
590 | return 0; | |
591 | } | |
592 | ||
593 | static struct i2c_driver dummy_driver = { | |
594 | .driver.name = "dummy", | |
d2653e92 JD |
595 | .probe = dummy_probe, |
596 | .remove = dummy_remove, | |
60b129d7 | 597 | .id_table = dummy_id, |
e9f1373b DB |
598 | }; |
599 | ||
600 | /** | |
601 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
602 | * @adapter: the adapter managing the device | |
603 | * @address: seven bit address to be used | |
e9f1373b DB |
604 | * Context: can sleep |
605 | * | |
606 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
607 | * with devices that consume multiple addresses. Examples of such chips | |
608 | * include various EEPROMS (like 24c04 and 24c08 models). | |
609 | * | |
610 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
611 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
612 | * And second, this prevents the specified address from being bound to a | |
613 | * different driver. | |
614 | * | |
615 | * This returns the new i2c client, which should be saved for later use with | |
616 | * i2c_unregister_device(); or NULL to indicate an error. | |
617 | */ | |
09b8ce0a | 618 | struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
619 | { |
620 | struct i2c_board_info info = { | |
60b129d7 | 621 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
622 | }; |
623 | ||
e9f1373b DB |
624 | return i2c_new_device(adapter, &info); |
625 | } | |
626 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
627 | ||
f37dd80a DB |
628 | /* ------------------------------------------------------------------------- */ |
629 | ||
16ffadfc DB |
630 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
631 | ||
83eaaed0 | 632 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 633 | { |
ef2c8321 | 634 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
635 | complete(&adap->dev_released); |
636 | } | |
637 | ||
99cd8e25 JD |
638 | /* |
639 | * Let users instantiate I2C devices through sysfs. This can be used when | |
640 | * platform initialization code doesn't contain the proper data for | |
641 | * whatever reason. Also useful for drivers that do device detection and | |
642 | * detection fails, either because the device uses an unexpected address, | |
643 | * or this is a compatible device with different ID register values. | |
644 | * | |
645 | * Parameter checking may look overzealous, but we really don't want | |
646 | * the user to provide incorrect parameters. | |
647 | */ | |
648 | static ssize_t | |
649 | i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, | |
650 | const char *buf, size_t count) | |
651 | { | |
652 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
653 | struct i2c_board_info info; | |
654 | struct i2c_client *client; | |
655 | char *blank, end; | |
656 | int res; | |
657 | ||
99cd8e25 JD |
658 | memset(&info, 0, sizeof(struct i2c_board_info)); |
659 | ||
660 | blank = strchr(buf, ' '); | |
661 | if (!blank) { | |
662 | dev_err(dev, "%s: Missing parameters\n", "new_device"); | |
663 | return -EINVAL; | |
664 | } | |
665 | if (blank - buf > I2C_NAME_SIZE - 1) { | |
666 | dev_err(dev, "%s: Invalid device name\n", "new_device"); | |
667 | return -EINVAL; | |
668 | } | |
669 | memcpy(info.type, buf, blank - buf); | |
670 | ||
671 | /* Parse remaining parameters, reject extra parameters */ | |
672 | res = sscanf(++blank, "%hi%c", &info.addr, &end); | |
673 | if (res < 1) { | |
674 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); | |
675 | return -EINVAL; | |
676 | } | |
677 | if (res > 1 && end != '\n') { | |
678 | dev_err(dev, "%s: Extra parameters\n", "new_device"); | |
679 | return -EINVAL; | |
680 | } | |
681 | ||
99cd8e25 JD |
682 | client = i2c_new_device(adap, &info); |
683 | if (!client) | |
3a89db5f | 684 | return -EINVAL; |
99cd8e25 JD |
685 | |
686 | /* Keep track of the added device */ | |
dafc50d1 | 687 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff | 688 | list_add_tail(&client->detected, &adap->userspace_clients); |
dafc50d1 | 689 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
690 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
691 | info.type, info.addr); | |
692 | ||
693 | return count; | |
694 | } | |
695 | ||
696 | /* | |
697 | * And of course let the users delete the devices they instantiated, if | |
698 | * they got it wrong. This interface can only be used to delete devices | |
699 | * instantiated by i2c_sysfs_new_device above. This guarantees that we | |
700 | * don't delete devices to which some kernel code still has references. | |
701 | * | |
702 | * Parameter checking may look overzealous, but we really don't want | |
703 | * the user to delete the wrong device. | |
704 | */ | |
705 | static ssize_t | |
706 | i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, | |
707 | const char *buf, size_t count) | |
708 | { | |
709 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
710 | struct i2c_client *client, *next; | |
711 | unsigned short addr; | |
712 | char end; | |
713 | int res; | |
714 | ||
715 | /* Parse parameters, reject extra parameters */ | |
716 | res = sscanf(buf, "%hi%c", &addr, &end); | |
717 | if (res < 1) { | |
718 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); | |
719 | return -EINVAL; | |
720 | } | |
721 | if (res > 1 && end != '\n') { | |
722 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); | |
723 | return -EINVAL; | |
724 | } | |
725 | ||
726 | /* Make sure the device was added through sysfs */ | |
727 | res = -ENOENT; | |
dafc50d1 | 728 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff JD |
729 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
730 | detected) { | |
731 | if (client->addr == addr) { | |
99cd8e25 JD |
732 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
733 | "delete_device", client->name, client->addr); | |
734 | ||
735 | list_del(&client->detected); | |
736 | i2c_unregister_device(client); | |
737 | res = count; | |
738 | break; | |
739 | } | |
740 | } | |
dafc50d1 | 741 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
742 | |
743 | if (res < 0) | |
744 | dev_err(dev, "%s: Can't find device in list\n", | |
745 | "delete_device"); | |
746 | return res; | |
747 | } | |
748 | ||
4f8cf824 JD |
749 | static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); |
750 | static DEVICE_ATTR(delete_device, S_IWUSR, NULL, i2c_sysfs_delete_device); | |
751 | ||
752 | static struct attribute *i2c_adapter_attrs[] = { | |
753 | &dev_attr_name.attr, | |
754 | &dev_attr_new_device.attr, | |
755 | &dev_attr_delete_device.attr, | |
756 | NULL | |
757 | }; | |
758 | ||
759 | static struct attribute_group i2c_adapter_attr_group = { | |
760 | .attrs = i2c_adapter_attrs, | |
761 | }; | |
762 | ||
763 | static const struct attribute_group *i2c_adapter_attr_groups[] = { | |
764 | &i2c_adapter_attr_group, | |
765 | NULL | |
16ffadfc | 766 | }; |
b119dc3f | 767 | |
0826374b | 768 | struct device_type i2c_adapter_type = { |
4f8cf824 JD |
769 | .groups = i2c_adapter_attr_groups, |
770 | .release = i2c_adapter_dev_release, | |
1da177e4 | 771 | }; |
0826374b | 772 | EXPORT_SYMBOL_GPL(i2c_adapter_type); |
1da177e4 | 773 | |
2bb5095a JD |
774 | #ifdef CONFIG_I2C_COMPAT |
775 | static struct class_compat *i2c_adapter_compat_class; | |
776 | #endif | |
777 | ||
9c1600ed DB |
778 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
779 | { | |
780 | struct i2c_devinfo *devinfo; | |
781 | ||
f18c41da | 782 | down_read(&__i2c_board_lock); |
9c1600ed DB |
783 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
784 | if (devinfo->busnum == adapter->nr | |
785 | && !i2c_new_device(adapter, | |
786 | &devinfo->board_info)) | |
09b8ce0a ZX |
787 | dev_err(&adapter->dev, |
788 | "Can't create device at 0x%02x\n", | |
9c1600ed DB |
789 | devinfo->board_info.addr); |
790 | } | |
f18c41da | 791 | up_read(&__i2c_board_lock); |
9c1600ed DB |
792 | } |
793 | ||
69b0089a JD |
794 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
795 | struct i2c_adapter *adap) | |
026526f5 | 796 | { |
4735c98f JD |
797 | /* Detect supported devices on that bus, and instantiate them */ |
798 | i2c_detect(adap, driver); | |
799 | ||
800 | /* Let legacy drivers scan this bus for matching devices */ | |
026526f5 JD |
801 | if (driver->attach_adapter) { |
802 | /* We ignore the return code; if it fails, too bad */ | |
803 | driver->attach_adapter(adap); | |
804 | } | |
805 | return 0; | |
806 | } | |
807 | ||
69b0089a JD |
808 | static int __process_new_adapter(struct device_driver *d, void *data) |
809 | { | |
810 | return i2c_do_add_adapter(to_i2c_driver(d), data); | |
811 | } | |
812 | ||
6e13e641 | 813 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 814 | { |
d6703281 | 815 | int res = 0; |
1da177e4 | 816 | |
1d0b19c9 | 817 | /* Can't register until after driver model init */ |
35fc37f8 JD |
818 | if (unlikely(WARN_ON(!i2c_bus_type.p))) { |
819 | res = -EAGAIN; | |
820 | goto out_list; | |
821 | } | |
1d0b19c9 | 822 | |
2236baa7 JD |
823 | /* Sanity checks */ |
824 | if (unlikely(adap->name[0] == '\0')) { | |
825 | pr_err("i2c-core: Attempt to register an adapter with " | |
826 | "no name!\n"); | |
827 | return -EINVAL; | |
828 | } | |
829 | if (unlikely(!adap->algo)) { | |
830 | pr_err("i2c-core: Attempt to register adapter '%s' with " | |
831 | "no algo!\n", adap->name); | |
832 | return -EINVAL; | |
833 | } | |
834 | ||
194684e5 | 835 | rt_mutex_init(&adap->bus_lock); |
dafc50d1 | 836 | mutex_init(&adap->userspace_clients_lock); |
6629dcff | 837 | INIT_LIST_HEAD(&adap->userspace_clients); |
1da177e4 | 838 | |
8fcfef6e JD |
839 | /* Set default timeout to 1 second if not already set */ |
840 | if (adap->timeout == 0) | |
841 | adap->timeout = HZ; | |
842 | ||
27d9c183 | 843 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
4f8cf824 JD |
844 | adap->dev.bus = &i2c_bus_type; |
845 | adap->dev.type = &i2c_adapter_type; | |
b119c6c9 JD |
846 | res = device_register(&adap->dev); |
847 | if (res) | |
848 | goto out_list; | |
1da177e4 | 849 | |
b6d7b3d1 JD |
850 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
851 | ||
2bb5095a JD |
852 | #ifdef CONFIG_I2C_COMPAT |
853 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, | |
854 | adap->dev.parent); | |
855 | if (res) | |
856 | dev_warn(&adap->dev, | |
857 | "Failed to create compatibility class link\n"); | |
858 | #endif | |
859 | ||
729d6dd5 | 860 | /* create pre-declared device nodes */ |
6e13e641 DB |
861 | if (adap->nr < __i2c_first_dynamic_bus_num) |
862 | i2c_scan_static_board_info(adap); | |
863 | ||
4735c98f | 864 | /* Notify drivers */ |
35fc37f8 | 865 | mutex_lock(&core_lock); |
d6703281 | 866 | bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); |
caada32a | 867 | mutex_unlock(&core_lock); |
35fc37f8 JD |
868 | |
869 | return 0; | |
b119c6c9 | 870 | |
b119c6c9 | 871 | out_list: |
35fc37f8 | 872 | mutex_lock(&core_lock); |
b119c6c9 | 873 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 JD |
874 | mutex_unlock(&core_lock); |
875 | return res; | |
1da177e4 LT |
876 | } |
877 | ||
6e13e641 DB |
878 | /** |
879 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
880 | * @adapter: the adapter to add | |
d64f73be | 881 | * Context: can sleep |
6e13e641 DB |
882 | * |
883 | * This routine is used to declare an I2C adapter when its bus number | |
884 | * doesn't matter. Examples: for I2C adapters dynamically added by | |
885 | * USB links or PCI plugin cards. | |
886 | * | |
887 | * When this returns zero, a new bus number was allocated and stored | |
888 | * in adap->nr, and the specified adapter became available for clients. | |
889 | * Otherwise, a negative errno value is returned. | |
890 | */ | |
891 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
892 | { | |
893 | int id, res = 0; | |
894 | ||
895 | retry: | |
896 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
897 | return -ENOMEM; | |
898 | ||
caada32a | 899 | mutex_lock(&core_lock); |
6e13e641 DB |
900 | /* "above" here means "above or equal to", sigh */ |
901 | res = idr_get_new_above(&i2c_adapter_idr, adapter, | |
902 | __i2c_first_dynamic_bus_num, &id); | |
caada32a | 903 | mutex_unlock(&core_lock); |
6e13e641 DB |
904 | |
905 | if (res < 0) { | |
906 | if (res == -EAGAIN) | |
907 | goto retry; | |
908 | return res; | |
909 | } | |
910 | ||
911 | adapter->nr = id; | |
912 | return i2c_register_adapter(adapter); | |
913 | } | |
914 | EXPORT_SYMBOL(i2c_add_adapter); | |
915 | ||
916 | /** | |
917 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
918 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 919 | * Context: can sleep |
6e13e641 DB |
920 | * |
921 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
922 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
923 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
924 | * is used to properly configure I2C devices. |
925 | * | |
926 | * If no devices have pre-been declared for this bus, then be sure to | |
927 | * register the adapter before any dynamically allocated ones. Otherwise | |
928 | * the required bus ID may not be available. | |
929 | * | |
930 | * When this returns zero, the specified adapter became available for | |
931 | * clients using the bus number provided in adap->nr. Also, the table | |
932 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
933 | * and the appropriate driver model device nodes are created. Otherwise, a | |
934 | * negative errno value is returned. | |
935 | */ | |
936 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
937 | { | |
938 | int id; | |
939 | int status; | |
940 | ||
941 | if (adap->nr & ~MAX_ID_MASK) | |
942 | return -EINVAL; | |
943 | ||
944 | retry: | |
945 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
946 | return -ENOMEM; | |
947 | ||
caada32a | 948 | mutex_lock(&core_lock); |
6e13e641 DB |
949 | /* "above" here means "above or equal to", sigh; |
950 | * we need the "equal to" result to force the result | |
951 | */ | |
952 | status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id); | |
953 | if (status == 0 && id != adap->nr) { | |
954 | status = -EBUSY; | |
955 | idr_remove(&i2c_adapter_idr, id); | |
956 | } | |
caada32a | 957 | mutex_unlock(&core_lock); |
6e13e641 DB |
958 | if (status == -EAGAIN) |
959 | goto retry; | |
960 | ||
961 | if (status == 0) | |
962 | status = i2c_register_adapter(adap); | |
963 | return status; | |
964 | } | |
965 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
966 | ||
69b0089a JD |
967 | static int i2c_do_del_adapter(struct i2c_driver *driver, |
968 | struct i2c_adapter *adapter) | |
026526f5 | 969 | { |
4735c98f | 970 | struct i2c_client *client, *_n; |
026526f5 JD |
971 | int res; |
972 | ||
acec211c JD |
973 | /* Remove the devices we created ourselves as the result of hardware |
974 | * probing (using a driver's detect method) */ | |
4735c98f JD |
975 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
976 | if (client->adapter == adapter) { | |
977 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", | |
978 | client->name, client->addr); | |
979 | list_del(&client->detected); | |
980 | i2c_unregister_device(client); | |
981 | } | |
982 | } | |
983 | ||
026526f5 JD |
984 | if (!driver->detach_adapter) |
985 | return 0; | |
986 | res = driver->detach_adapter(adapter); | |
987 | if (res) | |
988 | dev_err(&adapter->dev, "detach_adapter failed (%d) " | |
989 | "for driver [%s]\n", res, driver->driver.name); | |
990 | return res; | |
991 | } | |
992 | ||
e549c2b5 | 993 | static int __unregister_client(struct device *dev, void *dummy) |
5219bf88 JD |
994 | { |
995 | struct i2c_client *client = i2c_verify_client(dev); | |
996 | if (client && strcmp(client->name, "dummy")) | |
997 | i2c_unregister_device(client); | |
998 | return 0; | |
999 | } | |
1000 | ||
1001 | static int __unregister_dummy(struct device *dev, void *dummy) | |
e549c2b5 JD |
1002 | { |
1003 | struct i2c_client *client = i2c_verify_client(dev); | |
1004 | if (client) | |
1005 | i2c_unregister_device(client); | |
1006 | return 0; | |
1007 | } | |
1008 | ||
69b0089a JD |
1009 | static int __process_removed_adapter(struct device_driver *d, void *data) |
1010 | { | |
1011 | return i2c_do_del_adapter(to_i2c_driver(d), data); | |
1012 | } | |
1013 | ||
d64f73be DB |
1014 | /** |
1015 | * i2c_del_adapter - unregister I2C adapter | |
1016 | * @adap: the adapter being unregistered | |
1017 | * Context: can sleep | |
1018 | * | |
1019 | * This unregisters an I2C adapter which was previously registered | |
1020 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
1021 | */ | |
1da177e4 LT |
1022 | int i2c_del_adapter(struct i2c_adapter *adap) |
1023 | { | |
1da177e4 | 1024 | int res = 0; |
35fc37f8 | 1025 | struct i2c_adapter *found; |
bbd2d9c9 | 1026 | struct i2c_client *client, *next; |
1da177e4 LT |
1027 | |
1028 | /* First make sure that this adapter was ever added */ | |
35fc37f8 JD |
1029 | mutex_lock(&core_lock); |
1030 | found = idr_find(&i2c_adapter_idr, adap->nr); | |
1031 | mutex_unlock(&core_lock); | |
1032 | if (found != adap) { | |
b6d7b3d1 JD |
1033 | pr_debug("i2c-core: attempting to delete unregistered " |
1034 | "adapter [%s]\n", adap->name); | |
35fc37f8 | 1035 | return -EINVAL; |
1da177e4 LT |
1036 | } |
1037 | ||
026526f5 | 1038 | /* Tell drivers about this removal */ |
35fc37f8 | 1039 | mutex_lock(&core_lock); |
026526f5 | 1040 | res = bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 1041 | __process_removed_adapter); |
35fc37f8 | 1042 | mutex_unlock(&core_lock); |
026526f5 | 1043 | if (res) |
35fc37f8 | 1044 | return res; |
1da177e4 | 1045 | |
bbd2d9c9 | 1046 | /* Remove devices instantiated from sysfs */ |
dafc50d1 | 1047 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff JD |
1048 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1049 | detected) { | |
1050 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, | |
1051 | client->addr); | |
1052 | list_del(&client->detected); | |
1053 | i2c_unregister_device(client); | |
bbd2d9c9 | 1054 | } |
dafc50d1 | 1055 | mutex_unlock(&adap->userspace_clients_lock); |
bbd2d9c9 | 1056 | |
e549c2b5 | 1057 | /* Detach any active clients. This can't fail, thus we do not |
5219bf88 JD |
1058 | * check the returned value. This is a two-pass process, because |
1059 | * we can't remove the dummy devices during the first pass: they | |
1060 | * could have been instantiated by real devices wishing to clean | |
1061 | * them up properly, so we give them a chance to do that first. */ | |
e549c2b5 | 1062 | res = device_for_each_child(&adap->dev, NULL, __unregister_client); |
5219bf88 | 1063 | res = device_for_each_child(&adap->dev, NULL, __unregister_dummy); |
1da177e4 | 1064 | |
2bb5095a JD |
1065 | #ifdef CONFIG_I2C_COMPAT |
1066 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, | |
1067 | adap->dev.parent); | |
1068 | #endif | |
1069 | ||
c5567521 TLSC |
1070 | /* device name is gone after device_unregister */ |
1071 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); | |
1072 | ||
1da177e4 LT |
1073 | /* clean up the sysfs representation */ |
1074 | init_completion(&adap->dev_released); | |
1da177e4 | 1075 | device_unregister(&adap->dev); |
1da177e4 LT |
1076 | |
1077 | /* wait for sysfs to drop all references */ | |
1078 | wait_for_completion(&adap->dev_released); | |
1da177e4 | 1079 | |
6e13e641 | 1080 | /* free bus id */ |
35fc37f8 | 1081 | mutex_lock(&core_lock); |
1da177e4 | 1082 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 | 1083 | mutex_unlock(&core_lock); |
1da177e4 | 1084 | |
bd4bc3db JD |
1085 | /* Clear the device structure in case this adapter is ever going to be |
1086 | added again */ | |
1087 | memset(&adap->dev, 0, sizeof(adap->dev)); | |
1088 | ||
35fc37f8 | 1089 | return 0; |
1da177e4 | 1090 | } |
c0564606 | 1091 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 LT |
1092 | |
1093 | ||
7b4fbc50 DB |
1094 | /* ------------------------------------------------------------------------- */ |
1095 | ||
69b0089a | 1096 | static int __process_new_driver(struct device *dev, void *data) |
7f101a97 | 1097 | { |
4f8cf824 JD |
1098 | if (dev->type != &i2c_adapter_type) |
1099 | return 0; | |
69b0089a | 1100 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
7f101a97 DY |
1101 | } |
1102 | ||
7b4fbc50 DB |
1103 | /* |
1104 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
729d6dd5 | 1105 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
1da177e4 LT |
1106 | */ |
1107 | ||
de59cf9e | 1108 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 1109 | { |
7eebcb7c | 1110 | int res; |
1da177e4 | 1111 | |
1d0b19c9 DB |
1112 | /* Can't register until after driver model init */ |
1113 | if (unlikely(WARN_ON(!i2c_bus_type.p))) | |
1114 | return -EAGAIN; | |
1115 | ||
1da177e4 | 1116 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 1117 | driver->driver.owner = owner; |
1da177e4 | 1118 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 1119 | |
729d6dd5 | 1120 | /* When registration returns, the driver core |
6e13e641 DB |
1121 | * will have called probe() for all matching-but-unbound devices. |
1122 | */ | |
1da177e4 LT |
1123 | res = driver_register(&driver->driver); |
1124 | if (res) | |
7eebcb7c | 1125 | return res; |
438d6c2c | 1126 | |
f4e8db31 MB |
1127 | /* Drivers should switch to dev_pm_ops instead. */ |
1128 | if (driver->suspend) | |
1129 | pr_warn("i2c-core: driver [%s] using legacy suspend method\n", | |
1130 | driver->driver.name); | |
1131 | if (driver->resume) | |
1132 | pr_warn("i2c-core: driver [%s] using legacy resume method\n", | |
1133 | driver->driver.name); | |
1134 | ||
35d8b2e6 | 1135 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 1136 | |
4735c98f JD |
1137 | INIT_LIST_HEAD(&driver->clients); |
1138 | /* Walk the adapters that are already present */ | |
35fc37f8 | 1139 | mutex_lock(&core_lock); |
69b0089a | 1140 | bus_for_each_dev(&i2c_bus_type, NULL, driver, __process_new_driver); |
7f101a97 | 1141 | mutex_unlock(&core_lock); |
35fc37f8 | 1142 | |
7f101a97 DY |
1143 | return 0; |
1144 | } | |
1145 | EXPORT_SYMBOL(i2c_register_driver); | |
1146 | ||
69b0089a | 1147 | static int __process_removed_driver(struct device *dev, void *data) |
7f101a97 | 1148 | { |
4f8cf824 JD |
1149 | if (dev->type != &i2c_adapter_type) |
1150 | return 0; | |
69b0089a | 1151 | return i2c_do_del_adapter(data, to_i2c_adapter(dev)); |
1da177e4 LT |
1152 | } |
1153 | ||
a1d9e6e4 DB |
1154 | /** |
1155 | * i2c_del_driver - unregister I2C driver | |
1156 | * @driver: the driver being unregistered | |
d64f73be | 1157 | * Context: can sleep |
a1d9e6e4 | 1158 | */ |
b3e82096 | 1159 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 1160 | { |
caada32a | 1161 | mutex_lock(&core_lock); |
69b0089a | 1162 | bus_for_each_dev(&i2c_bus_type, NULL, driver, __process_removed_driver); |
35fc37f8 | 1163 | mutex_unlock(&core_lock); |
1da177e4 LT |
1164 | |
1165 | driver_unregister(&driver->driver); | |
35d8b2e6 | 1166 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 1167 | } |
c0564606 | 1168 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 1169 | |
7b4fbc50 DB |
1170 | /* ------------------------------------------------------------------------- */ |
1171 | ||
e48d3319 JD |
1172 | /** |
1173 | * i2c_use_client - increments the reference count of the i2c client structure | |
1174 | * @client: the client being referenced | |
1175 | * | |
1176 | * Each live reference to a client should be refcounted. The driver model does | |
1177 | * that automatically as part of driver binding, so that most drivers don't | |
1178 | * need to do this explicitly: they hold a reference until they're unbound | |
1179 | * from the device. | |
1180 | * | |
1181 | * A pointer to the client with the incremented reference counter is returned. | |
1182 | */ | |
1183 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 1184 | { |
6ea438ec DB |
1185 | if (client && get_device(&client->dev)) |
1186 | return client; | |
1187 | return NULL; | |
1da177e4 | 1188 | } |
c0564606 | 1189 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 1190 | |
e48d3319 JD |
1191 | /** |
1192 | * i2c_release_client - release a use of the i2c client structure | |
1193 | * @client: the client being no longer referenced | |
1194 | * | |
1195 | * Must be called when a user of a client is finished with it. | |
1196 | */ | |
1197 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 1198 | { |
6ea438ec DB |
1199 | if (client) |
1200 | put_device(&client->dev); | |
1da177e4 | 1201 | } |
c0564606 | 1202 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 1203 | |
9b766b81 DB |
1204 | struct i2c_cmd_arg { |
1205 | unsigned cmd; | |
1206 | void *arg; | |
1207 | }; | |
1208 | ||
1209 | static int i2c_cmd(struct device *dev, void *_arg) | |
1210 | { | |
1211 | struct i2c_client *client = i2c_verify_client(dev); | |
1212 | struct i2c_cmd_arg *arg = _arg; | |
1213 | ||
1214 | if (client && client->driver && client->driver->command) | |
1215 | client->driver->command(client, arg->cmd, arg->arg); | |
1216 | return 0; | |
1217 | } | |
1218 | ||
1da177e4 LT |
1219 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
1220 | { | |
9b766b81 | 1221 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 1222 | |
9b766b81 DB |
1223 | cmd_arg.cmd = cmd; |
1224 | cmd_arg.arg = arg; | |
1225 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 1226 | } |
c0564606 | 1227 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 LT |
1228 | |
1229 | static int __init i2c_init(void) | |
1230 | { | |
1231 | int retval; | |
1232 | ||
1233 | retval = bus_register(&i2c_bus_type); | |
1da177e4 LT |
1234 | if (retval) |
1235 | return retval; | |
2bb5095a JD |
1236 | #ifdef CONFIG_I2C_COMPAT |
1237 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); | |
1238 | if (!i2c_adapter_compat_class) { | |
1239 | retval = -ENOMEM; | |
1240 | goto bus_err; | |
1241 | } | |
1242 | #endif | |
e9f1373b DB |
1243 | retval = i2c_add_driver(&dummy_driver); |
1244 | if (retval) | |
2bb5095a | 1245 | goto class_err; |
e9f1373b DB |
1246 | return 0; |
1247 | ||
2bb5095a JD |
1248 | class_err: |
1249 | #ifdef CONFIG_I2C_COMPAT | |
1250 | class_compat_unregister(i2c_adapter_compat_class); | |
e9f1373b | 1251 | bus_err: |
2bb5095a | 1252 | #endif |
e9f1373b DB |
1253 | bus_unregister(&i2c_bus_type); |
1254 | return retval; | |
1da177e4 LT |
1255 | } |
1256 | ||
1257 | static void __exit i2c_exit(void) | |
1258 | { | |
e9f1373b | 1259 | i2c_del_driver(&dummy_driver); |
2bb5095a JD |
1260 | #ifdef CONFIG_I2C_COMPAT |
1261 | class_compat_unregister(i2c_adapter_compat_class); | |
1262 | #endif | |
1da177e4 LT |
1263 | bus_unregister(&i2c_bus_type); |
1264 | } | |
1265 | ||
a10f9e7c DB |
1266 | /* We must initialize early, because some subsystems register i2c drivers |
1267 | * in subsys_initcall() code, but are linked (and initialized) before i2c. | |
1268 | */ | |
1269 | postcore_initcall(i2c_init); | |
1da177e4 LT |
1270 | module_exit(i2c_exit); |
1271 | ||
1272 | /* ---------------------------------------------------- | |
1273 | * the functional interface to the i2c busses. | |
1274 | * ---------------------------------------------------- | |
1275 | */ | |
1276 | ||
a1cdedac DB |
1277 | /** |
1278 | * i2c_transfer - execute a single or combined I2C message | |
1279 | * @adap: Handle to I2C bus | |
1280 | * @msgs: One or more messages to execute before STOP is issued to | |
1281 | * terminate the operation; each message begins with a START. | |
1282 | * @num: Number of messages to be executed. | |
1283 | * | |
1284 | * Returns negative errno, else the number of messages executed. | |
1285 | * | |
1286 | * Note that there is no requirement that each message be sent to | |
1287 | * the same slave address, although that is the most common model. | |
1288 | */ | |
09b8ce0a | 1289 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
1da177e4 | 1290 | { |
66b650f0 CW |
1291 | unsigned long orig_jiffies; |
1292 | int ret, try; | |
1da177e4 | 1293 | |
a1cdedac DB |
1294 | /* REVISIT the fault reporting model here is weak: |
1295 | * | |
1296 | * - When we get an error after receiving N bytes from a slave, | |
1297 | * there is no way to report "N". | |
1298 | * | |
1299 | * - When we get a NAK after transmitting N bytes to a slave, | |
1300 | * there is no way to report "N" ... or to let the master | |
1301 | * continue executing the rest of this combined message, if | |
1302 | * that's the appropriate response. | |
1303 | * | |
1304 | * - When for example "num" is two and we successfully complete | |
1305 | * the first message but get an error part way through the | |
1306 | * second, it's unclear whether that should be reported as | |
1307 | * one (discarding status on the second message) or errno | |
1308 | * (discarding status on the first one). | |
1309 | */ | |
1310 | ||
1da177e4 LT |
1311 | if (adap->algo->master_xfer) { |
1312 | #ifdef DEBUG | |
1313 | for (ret = 0; ret < num; ret++) { | |
1314 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
1315 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
1316 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
1317 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
1318 | } |
1319 | #endif | |
1320 | ||
cea443a8 | 1321 | if (in_atomic() || irqs_disabled()) { |
fe61e07e | 1322 | ret = i2c_trylock_adapter(adap); |
cea443a8 MR |
1323 | if (!ret) |
1324 | /* I2C activity is ongoing. */ | |
1325 | return -EAGAIN; | |
1326 | } else { | |
fe61e07e | 1327 | i2c_lock_adapter(adap); |
cea443a8 MR |
1328 | } |
1329 | ||
66b650f0 CW |
1330 | /* Retry automatically on arbitration loss */ |
1331 | orig_jiffies = jiffies; | |
1332 | for (ret = 0, try = 0; try <= adap->retries; try++) { | |
1333 | ret = adap->algo->master_xfer(adap, msgs, num); | |
1334 | if (ret != -EAGAIN) | |
1335 | break; | |
1336 | if (time_after(jiffies, orig_jiffies + adap->timeout)) | |
1337 | break; | |
1338 | } | |
fe61e07e | 1339 | i2c_unlock_adapter(adap); |
1da177e4 LT |
1340 | |
1341 | return ret; | |
1342 | } else { | |
1343 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
24a5bb7b | 1344 | return -EOPNOTSUPP; |
1da177e4 LT |
1345 | } |
1346 | } | |
c0564606 | 1347 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 | 1348 | |
a1cdedac DB |
1349 | /** |
1350 | * i2c_master_send - issue a single I2C message in master transmit mode | |
1351 | * @client: Handle to slave device | |
1352 | * @buf: Data that will be written to the slave | |
0c43ea54 | 1353 | * @count: How many bytes to write, must be less than 64k since msg.len is u16 |
a1cdedac DB |
1354 | * |
1355 | * Returns negative errno, or else the number of bytes written. | |
1356 | */ | |
0cc43a18 | 1357 | int i2c_master_send(const struct i2c_client *client, const char *buf, int count) |
1da177e4 LT |
1358 | { |
1359 | int ret; | |
7225acf4 | 1360 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
1361 | struct i2c_msg msg; |
1362 | ||
815f55f2 JD |
1363 | msg.addr = client->addr; |
1364 | msg.flags = client->flags & I2C_M_TEN; | |
1365 | msg.len = count; | |
1366 | msg.buf = (char *)buf; | |
438d6c2c | 1367 | |
815f55f2 | 1368 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 1369 | |
815f55f2 JD |
1370 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes |
1371 | transmitted, else error code. */ | |
1372 | return (ret == 1) ? count : ret; | |
1da177e4 | 1373 | } |
c0564606 | 1374 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 | 1375 | |
a1cdedac DB |
1376 | /** |
1377 | * i2c_master_recv - issue a single I2C message in master receive mode | |
1378 | * @client: Handle to slave device | |
1379 | * @buf: Where to store data read from slave | |
0c43ea54 | 1380 | * @count: How many bytes to read, must be less than 64k since msg.len is u16 |
a1cdedac DB |
1381 | * |
1382 | * Returns negative errno, or else the number of bytes read. | |
1383 | */ | |
0cc43a18 | 1384 | int i2c_master_recv(const struct i2c_client *client, char *buf, int count) |
1da177e4 | 1385 | { |
7225acf4 | 1386 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
1387 | struct i2c_msg msg; |
1388 | int ret; | |
815f55f2 JD |
1389 | |
1390 | msg.addr = client->addr; | |
1391 | msg.flags = client->flags & I2C_M_TEN; | |
1392 | msg.flags |= I2C_M_RD; | |
1393 | msg.len = count; | |
1394 | msg.buf = buf; | |
1395 | ||
1396 | ret = i2c_transfer(adap, &msg, 1); | |
1397 | ||
1398 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes | |
1399 | transmitted, else error code. */ | |
1400 | return (ret == 1) ? count : ret; | |
1da177e4 | 1401 | } |
c0564606 | 1402 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 1403 | |
1da177e4 LT |
1404 | /* ---------------------------------------------------- |
1405 | * the i2c address scanning function | |
1406 | * Will not work for 10-bit addresses! | |
1407 | * ---------------------------------------------------- | |
1408 | */ | |
1da177e4 | 1409 | |
63e4e802 JD |
1410 | /* |
1411 | * Legacy default probe function, mostly relevant for SMBus. The default | |
1412 | * probe method is a quick write, but it is known to corrupt the 24RF08 | |
1413 | * EEPROMs due to a state machine bug, and could also irreversibly | |
1414 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, | |
1415 | * we use a short byte read instead. Also, some bus drivers don't implement | |
1416 | * quick write, so we fallback to a byte read in that case too. | |
1417 | * On x86, there is another special case for FSC hardware monitoring chips, | |
1418 | * which want regular byte reads (address 0x73.) Fortunately, these are the | |
1419 | * only known chips using this I2C address on PC hardware. | |
1420 | * Returns 1 if probe succeeded, 0 if not. | |
1421 | */ | |
1422 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) | |
1423 | { | |
1424 | int err; | |
1425 | union i2c_smbus_data dummy; | |
1426 | ||
1427 | #ifdef CONFIG_X86 | |
1428 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) | |
1429 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
1430 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1431 | I2C_SMBUS_BYTE_DATA, &dummy); | |
1432 | else | |
1433 | #endif | |
8031d79b JD |
1434 | if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) |
1435 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) | |
63e4e802 JD |
1436 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, |
1437 | I2C_SMBUS_QUICK, NULL); | |
8031d79b JD |
1438 | else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) |
1439 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1440 | I2C_SMBUS_BYTE, &dummy); | |
1441 | else { | |
1442 | dev_warn(&adap->dev, "No suitable probing method supported\n"); | |
1443 | err = -EOPNOTSUPP; | |
1444 | } | |
63e4e802 JD |
1445 | |
1446 | return err >= 0; | |
1447 | } | |
1448 | ||
ccfbbd08 | 1449 | static int i2c_detect_address(struct i2c_client *temp_client, |
4735c98f JD |
1450 | struct i2c_driver *driver) |
1451 | { | |
1452 | struct i2c_board_info info; | |
1453 | struct i2c_adapter *adapter = temp_client->adapter; | |
1454 | int addr = temp_client->addr; | |
1455 | int err; | |
1456 | ||
1457 | /* Make sure the address is valid */ | |
656b8761 JD |
1458 | err = i2c_check_addr_validity(addr); |
1459 | if (err) { | |
4735c98f JD |
1460 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
1461 | addr); | |
656b8761 | 1462 | return err; |
4735c98f JD |
1463 | } |
1464 | ||
1465 | /* Skip if already in use */ | |
3b5f794b | 1466 | if (i2c_check_addr_busy(adapter, addr)) |
4735c98f JD |
1467 | return 0; |
1468 | ||
ccfbbd08 | 1469 | /* Make sure there is something at this address */ |
63e4e802 JD |
1470 | if (!i2c_default_probe(adapter, addr)) |
1471 | return 0; | |
4735c98f JD |
1472 | |
1473 | /* Finally call the custom detection function */ | |
1474 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
1475 | info.addr = addr; | |
310ec792 | 1476 | err = driver->detect(temp_client, &info); |
4735c98f JD |
1477 | if (err) { |
1478 | /* -ENODEV is returned if the detection fails. We catch it | |
1479 | here as this isn't an error. */ | |
1480 | return err == -ENODEV ? 0 : err; | |
1481 | } | |
1482 | ||
1483 | /* Consistency check */ | |
1484 | if (info.type[0] == '\0') { | |
1485 | dev_err(&adapter->dev, "%s detection function provided " | |
1486 | "no name for 0x%x\n", driver->driver.name, | |
1487 | addr); | |
1488 | } else { | |
1489 | struct i2c_client *client; | |
1490 | ||
1491 | /* Detection succeeded, instantiate the device */ | |
1492 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", | |
1493 | info.type, info.addr); | |
1494 | client = i2c_new_device(adapter, &info); | |
1495 | if (client) | |
1496 | list_add_tail(&client->detected, &driver->clients); | |
1497 | else | |
1498 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", | |
1499 | info.type, info.addr); | |
1500 | } | |
1501 | return 0; | |
1502 | } | |
1503 | ||
1504 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) | |
1505 | { | |
c3813d6a | 1506 | const unsigned short *address_list; |
4735c98f JD |
1507 | struct i2c_client *temp_client; |
1508 | int i, err = 0; | |
1509 | int adap_id = i2c_adapter_id(adapter); | |
1510 | ||
c3813d6a JD |
1511 | address_list = driver->address_list; |
1512 | if (!driver->detect || !address_list) | |
4735c98f JD |
1513 | return 0; |
1514 | ||
51b54ba9 JD |
1515 | /* Stop here if the classes do not match */ |
1516 | if (!(adapter->class & driver->class)) | |
1517 | return 0; | |
1518 | ||
4735c98f JD |
1519 | /* Set up a temporary client to help detect callback */ |
1520 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); | |
1521 | if (!temp_client) | |
1522 | return -ENOMEM; | |
1523 | temp_client->adapter = adapter; | |
1524 | ||
c3813d6a | 1525 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
4735c98f | 1526 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
c3813d6a JD |
1527 | "addr 0x%02x\n", adap_id, address_list[i]); |
1528 | temp_client->addr = address_list[i]; | |
ccfbbd08 | 1529 | err = i2c_detect_address(temp_client, driver); |
51b54ba9 JD |
1530 | if (unlikely(err)) |
1531 | break; | |
4735c98f JD |
1532 | } |
1533 | ||
4735c98f JD |
1534 | kfree(temp_client); |
1535 | return err; | |
1536 | } | |
1537 | ||
d44f19d5 JD |
1538 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
1539 | { | |
1540 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
1541 | I2C_SMBUS_QUICK, NULL) >= 0; | |
1542 | } | |
1543 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); | |
1544 | ||
12b5053a JD |
1545 | struct i2c_client * |
1546 | i2c_new_probed_device(struct i2c_adapter *adap, | |
1547 | struct i2c_board_info *info, | |
9a94241a JD |
1548 | unsigned short const *addr_list, |
1549 | int (*probe)(struct i2c_adapter *, unsigned short addr)) | |
12b5053a JD |
1550 | { |
1551 | int i; | |
1552 | ||
8031d79b | 1553 | if (!probe) |
9a94241a | 1554 | probe = i2c_default_probe; |
12b5053a | 1555 | |
12b5053a JD |
1556 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
1557 | /* Check address validity */ | |
656b8761 | 1558 | if (i2c_check_addr_validity(addr_list[i]) < 0) { |
12b5053a JD |
1559 | dev_warn(&adap->dev, "Invalid 7-bit address " |
1560 | "0x%02x\n", addr_list[i]); | |
1561 | continue; | |
1562 | } | |
1563 | ||
1564 | /* Check address availability */ | |
3b5f794b | 1565 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
12b5053a JD |
1566 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
1567 | "use, not probing\n", addr_list[i]); | |
1568 | continue; | |
1569 | } | |
1570 | ||
63e4e802 | 1571 | /* Test address responsiveness */ |
9a94241a | 1572 | if (probe(adap, addr_list[i])) |
63e4e802 | 1573 | break; |
12b5053a | 1574 | } |
12b5053a JD |
1575 | |
1576 | if (addr_list[i] == I2C_CLIENT_END) { | |
1577 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
1578 | return NULL; | |
1579 | } | |
1580 | ||
1581 | info->addr = addr_list[i]; | |
1582 | return i2c_new_device(adap, info); | |
1583 | } | |
1584 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
1585 | ||
7225acf4 | 1586 | struct i2c_adapter *i2c_get_adapter(int id) |
1da177e4 | 1587 | { |
1da177e4 | 1588 | struct i2c_adapter *adapter; |
438d6c2c | 1589 | |
caada32a | 1590 | mutex_lock(&core_lock); |
1cf92b45 | 1591 | adapter = idr_find(&i2c_adapter_idr, id); |
a0920e10 MH |
1592 | if (adapter && !try_module_get(adapter->owner)) |
1593 | adapter = NULL; | |
1594 | ||
caada32a | 1595 | mutex_unlock(&core_lock); |
a0920e10 | 1596 | return adapter; |
1da177e4 | 1597 | } |
c0564606 | 1598 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
1599 | |
1600 | void i2c_put_adapter(struct i2c_adapter *adap) | |
1601 | { | |
1602 | module_put(adap->owner); | |
1603 | } | |
c0564606 | 1604 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
1605 | |
1606 | /* The SMBus parts */ | |
1607 | ||
438d6c2c | 1608 | #define POLY (0x1070U << 3) |
09b8ce0a | 1609 | static u8 crc8(u16 data) |
1da177e4 LT |
1610 | { |
1611 | int i; | |
438d6c2c | 1612 | |
7225acf4 | 1613 | for (i = 0; i < 8; i++) { |
438d6c2c | 1614 | if (data & 0x8000) |
1da177e4 LT |
1615 | data = data ^ POLY; |
1616 | data = data << 1; | |
1617 | } | |
1618 | return (u8)(data >> 8); | |
1619 | } | |
1620 | ||
421ef47b JD |
1621 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
1622 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
1623 | { |
1624 | int i; | |
1625 | ||
7225acf4 | 1626 | for (i = 0; i < count; i++) |
421ef47b | 1627 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
1628 | return crc; |
1629 | } | |
1630 | ||
421ef47b JD |
1631 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
1632 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 1633 | { |
421ef47b JD |
1634 | /* The address will be sent first */ |
1635 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
1636 | pec = i2c_smbus_pec(pec, &addr, 1); | |
1637 | ||
1638 | /* The data buffer follows */ | |
1639 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
1640 | } |
1641 | ||
421ef47b JD |
1642 | /* Used for write only transactions */ |
1643 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 1644 | { |
421ef47b JD |
1645 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
1646 | msg->len++; | |
1da177e4 LT |
1647 | } |
1648 | ||
421ef47b JD |
1649 | /* Return <0 on CRC error |
1650 | If there was a write before this read (most cases) we need to take the | |
1651 | partial CRC from the write part into account. | |
1652 | Note that this function does modify the message (we need to decrease the | |
1653 | message length to hide the CRC byte from the caller). */ | |
1654 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 1655 | { |
421ef47b JD |
1656 | u8 rpec = msg->buf[--msg->len]; |
1657 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 1658 | |
1da177e4 LT |
1659 | if (rpec != cpec) { |
1660 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
1661 | rpec, cpec); | |
24a5bb7b | 1662 | return -EBADMSG; |
1da177e4 | 1663 | } |
438d6c2c | 1664 | return 0; |
1da177e4 LT |
1665 | } |
1666 | ||
a1cdedac DB |
1667 | /** |
1668 | * i2c_smbus_read_byte - SMBus "receive byte" protocol | |
1669 | * @client: Handle to slave device | |
1670 | * | |
1671 | * This executes the SMBus "receive byte" protocol, returning negative errno | |
1672 | * else the byte received from the device. | |
1673 | */ | |
0cc43a18 | 1674 | s32 i2c_smbus_read_byte(const struct i2c_client *client) |
1da177e4 LT |
1675 | { |
1676 | union i2c_smbus_data data; | |
24a5bb7b DB |
1677 | int status; |
1678 | ||
1679 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1680 | I2C_SMBUS_READ, 0, | |
1681 | I2C_SMBUS_BYTE, &data); | |
1682 | return (status < 0) ? status : data.byte; | |
1da177e4 | 1683 | } |
c0564606 | 1684 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 | 1685 | |
a1cdedac DB |
1686 | /** |
1687 | * i2c_smbus_write_byte - SMBus "send byte" protocol | |
1688 | * @client: Handle to slave device | |
1689 | * @value: Byte to be sent | |
1690 | * | |
1691 | * This executes the SMBus "send byte" protocol, returning negative errno | |
1692 | * else zero on success. | |
1693 | */ | |
0cc43a18 | 1694 | s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) |
1da177e4 | 1695 | { |
7225acf4 | 1696 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
421ef47b | 1697 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 1698 | } |
c0564606 | 1699 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 | 1700 | |
a1cdedac DB |
1701 | /** |
1702 | * i2c_smbus_read_byte_data - SMBus "read byte" protocol | |
1703 | * @client: Handle to slave device | |
1704 | * @command: Byte interpreted by slave | |
1705 | * | |
1706 | * This executes the SMBus "read byte" protocol, returning negative errno | |
1707 | * else a data byte received from the device. | |
1708 | */ | |
0cc43a18 | 1709 | s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
1710 | { |
1711 | union i2c_smbus_data data; | |
24a5bb7b DB |
1712 | int status; |
1713 | ||
1714 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1715 | I2C_SMBUS_READ, command, | |
1716 | I2C_SMBUS_BYTE_DATA, &data); | |
1717 | return (status < 0) ? status : data.byte; | |
1da177e4 | 1718 | } |
c0564606 | 1719 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 | 1720 | |
a1cdedac DB |
1721 | /** |
1722 | * i2c_smbus_write_byte_data - SMBus "write byte" protocol | |
1723 | * @client: Handle to slave device | |
1724 | * @command: Byte interpreted by slave | |
1725 | * @value: Byte being written | |
1726 | * | |
1727 | * This executes the SMBus "write byte" protocol, returning negative errno | |
1728 | * else zero on success. | |
1729 | */ | |
0cc43a18 JD |
1730 | s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, |
1731 | u8 value) | |
1da177e4 LT |
1732 | { |
1733 | union i2c_smbus_data data; | |
1734 | data.byte = value; | |
7225acf4 FH |
1735 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1736 | I2C_SMBUS_WRITE, command, | |
1737 | I2C_SMBUS_BYTE_DATA, &data); | |
1da177e4 | 1738 | } |
c0564606 | 1739 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 | 1740 | |
a1cdedac DB |
1741 | /** |
1742 | * i2c_smbus_read_word_data - SMBus "read word" protocol | |
1743 | * @client: Handle to slave device | |
1744 | * @command: Byte interpreted by slave | |
1745 | * | |
1746 | * This executes the SMBus "read word" protocol, returning negative errno | |
1747 | * else a 16-bit unsigned "word" received from the device. | |
1748 | */ | |
0cc43a18 | 1749 | s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
1750 | { |
1751 | union i2c_smbus_data data; | |
24a5bb7b DB |
1752 | int status; |
1753 | ||
1754 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1755 | I2C_SMBUS_READ, command, | |
1756 | I2C_SMBUS_WORD_DATA, &data); | |
1757 | return (status < 0) ? status : data.word; | |
1da177e4 | 1758 | } |
c0564606 | 1759 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 | 1760 | |
a1cdedac DB |
1761 | /** |
1762 | * i2c_smbus_write_word_data - SMBus "write word" protocol | |
1763 | * @client: Handle to slave device | |
1764 | * @command: Byte interpreted by slave | |
1765 | * @value: 16-bit "word" being written | |
1766 | * | |
1767 | * This executes the SMBus "write word" protocol, returning negative errno | |
1768 | * else zero on success. | |
1769 | */ | |
0cc43a18 JD |
1770 | s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, |
1771 | u16 value) | |
1da177e4 LT |
1772 | { |
1773 | union i2c_smbus_data data; | |
1774 | data.word = value; | |
7225acf4 FH |
1775 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1776 | I2C_SMBUS_WRITE, command, | |
1777 | I2C_SMBUS_WORD_DATA, &data); | |
1da177e4 | 1778 | } |
c0564606 | 1779 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 1780 | |
596c88f4 PM |
1781 | /** |
1782 | * i2c_smbus_process_call - SMBus "process call" protocol | |
1783 | * @client: Handle to slave device | |
1784 | * @command: Byte interpreted by slave | |
1785 | * @value: 16-bit "word" being written | |
1786 | * | |
1787 | * This executes the SMBus "process call" protocol, returning negative errno | |
1788 | * else a 16-bit unsigned "word" received from the device. | |
1789 | */ | |
0cc43a18 JD |
1790 | s32 i2c_smbus_process_call(const struct i2c_client *client, u8 command, |
1791 | u16 value) | |
596c88f4 PM |
1792 | { |
1793 | union i2c_smbus_data data; | |
1794 | int status; | |
1795 | data.word = value; | |
1796 | ||
1797 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1798 | I2C_SMBUS_WRITE, command, | |
1799 | I2C_SMBUS_PROC_CALL, &data); | |
1800 | return (status < 0) ? status : data.word; | |
1801 | } | |
1802 | EXPORT_SYMBOL(i2c_smbus_process_call); | |
1803 | ||
a64ec07d | 1804 | /** |
a1cdedac | 1805 | * i2c_smbus_read_block_data - SMBus "block read" protocol |
a64ec07d | 1806 | * @client: Handle to slave device |
a1cdedac | 1807 | * @command: Byte interpreted by slave |
a64ec07d DB |
1808 | * @values: Byte array into which data will be read; big enough to hold |
1809 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
1810 | * | |
a1cdedac DB |
1811 | * This executes the SMBus "block read" protocol, returning negative errno |
1812 | * else the number of data bytes in the slave's response. | |
a64ec07d DB |
1813 | * |
1814 | * Note that using this function requires that the client's adapter support | |
1815 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
1816 | * support this; its emulation through I2C messaging relies on a specific | |
1817 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
1818 | */ | |
0cc43a18 | 1819 | s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, |
b86a1bc8 JD |
1820 | u8 *values) |
1821 | { | |
1822 | union i2c_smbus_data data; | |
24a5bb7b | 1823 | int status; |
b86a1bc8 | 1824 | |
24a5bb7b DB |
1825 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1826 | I2C_SMBUS_READ, command, | |
1827 | I2C_SMBUS_BLOCK_DATA, &data); | |
1828 | if (status) | |
1829 | return status; | |
b86a1bc8 JD |
1830 | |
1831 | memcpy(values, &data.block[1], data.block[0]); | |
1832 | return data.block[0]; | |
1833 | } | |
1834 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
1835 | ||
a1cdedac DB |
1836 | /** |
1837 | * i2c_smbus_write_block_data - SMBus "block write" protocol | |
1838 | * @client: Handle to slave device | |
1839 | * @command: Byte interpreted by slave | |
1840 | * @length: Size of data block; SMBus allows at most 32 bytes | |
1841 | * @values: Byte array which will be written. | |
1842 | * | |
1843 | * This executes the SMBus "block write" protocol, returning negative errno | |
1844 | * else zero on success. | |
1845 | */ | |
0cc43a18 | 1846 | s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 1847 | u8 length, const u8 *values) |
1da177e4 LT |
1848 | { |
1849 | union i2c_smbus_data data; | |
7656032b | 1850 | |
1da177e4 LT |
1851 | if (length > I2C_SMBUS_BLOCK_MAX) |
1852 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 1853 | data.block[0] = length; |
7656032b | 1854 | memcpy(&data.block[1], values, length); |
7225acf4 FH |
1855 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1856 | I2C_SMBUS_WRITE, command, | |
1857 | I2C_SMBUS_BLOCK_DATA, &data); | |
1da177e4 | 1858 | } |
c0564606 | 1859 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
1860 | |
1861 | /* Returns the number of read bytes */ | |
0cc43a18 | 1862 | s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, |
4b2643d7 | 1863 | u8 length, u8 *values) |
1da177e4 LT |
1864 | { |
1865 | union i2c_smbus_data data; | |
24a5bb7b | 1866 | int status; |
7656032b | 1867 | |
4b2643d7 JD |
1868 | if (length > I2C_SMBUS_BLOCK_MAX) |
1869 | length = I2C_SMBUS_BLOCK_MAX; | |
1870 | data.block[0] = length; | |
24a5bb7b DB |
1871 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
1872 | I2C_SMBUS_READ, command, | |
1873 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1874 | if (status < 0) | |
1875 | return status; | |
7656032b JD |
1876 | |
1877 | memcpy(values, &data.block[1], data.block[0]); | |
1878 | return data.block[0]; | |
1da177e4 | 1879 | } |
c0564606 | 1880 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 1881 | |
0cc43a18 | 1882 | s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 1883 | u8 length, const u8 *values) |
21bbd691 JD |
1884 | { |
1885 | union i2c_smbus_data data; | |
1886 | ||
1887 | if (length > I2C_SMBUS_BLOCK_MAX) | |
1888 | length = I2C_SMBUS_BLOCK_MAX; | |
1889 | data.block[0] = length; | |
1890 | memcpy(data.block + 1, values, length); | |
1891 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1892 | I2C_SMBUS_WRITE, command, | |
1893 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1894 | } | |
c0564606 | 1895 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 1896 | |
438d6c2c | 1897 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 1898 | No checking of parameters is done! */ |
7225acf4 FH |
1899 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, |
1900 | unsigned short flags, | |
1901 | char read_write, u8 command, int size, | |
1902 | union i2c_smbus_data *data) | |
1da177e4 LT |
1903 | { |
1904 | /* So we need to generate a series of msgs. In the case of writing, we | |
1905 | need to use only one message; when reading, we need two. We initialize | |
1906 | most things with sane defaults, to keep the code below somewhat | |
1907 | simpler. */ | |
5c50d188 HI |
1908 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
1909 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
7225acf4 | 1910 | int num = read_write == I2C_SMBUS_READ ? 2 : 1; |
438d6c2c | 1911 | struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 }, |
1da177e4 LT |
1912 | { addr, flags | I2C_M_RD, 0, msgbuf1 } |
1913 | }; | |
1914 | int i; | |
421ef47b | 1915 | u8 partial_pec = 0; |
24a5bb7b | 1916 | int status; |
1da177e4 LT |
1917 | |
1918 | msgbuf0[0] = command; | |
7225acf4 | 1919 | switch (size) { |
1da177e4 LT |
1920 | case I2C_SMBUS_QUICK: |
1921 | msg[0].len = 0; | |
1922 | /* Special case: The read/write field is used as data */ | |
f29d2e02 RK |
1923 | msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? |
1924 | I2C_M_RD : 0); | |
1da177e4 LT |
1925 | num = 1; |
1926 | break; | |
1927 | case I2C_SMBUS_BYTE: | |
1928 | if (read_write == I2C_SMBUS_READ) { | |
1929 | /* Special case: only a read! */ | |
1930 | msg[0].flags = I2C_M_RD | flags; | |
1931 | num = 1; | |
1932 | } | |
1933 | break; | |
1934 | case I2C_SMBUS_BYTE_DATA: | |
1935 | if (read_write == I2C_SMBUS_READ) | |
1936 | msg[1].len = 1; | |
1937 | else { | |
1938 | msg[0].len = 2; | |
1939 | msgbuf0[1] = data->byte; | |
1940 | } | |
1941 | break; | |
1942 | case I2C_SMBUS_WORD_DATA: | |
1943 | if (read_write == I2C_SMBUS_READ) | |
1944 | msg[1].len = 2; | |
1945 | else { | |
7225acf4 | 1946 | msg[0].len = 3; |
1da177e4 | 1947 | msgbuf0[1] = data->word & 0xff; |
7eff82c8 | 1948 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1949 | } |
1950 | break; | |
1951 | case I2C_SMBUS_PROC_CALL: | |
1952 | num = 2; /* Special case */ | |
1953 | read_write = I2C_SMBUS_READ; | |
1954 | msg[0].len = 3; | |
1955 | msg[1].len = 2; | |
1956 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1957 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1958 | break; |
1959 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 1960 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
1961 | msg[1].flags |= I2C_M_RECV_LEN; |
1962 | msg[1].len = 1; /* block length will be added by | |
1963 | the underlying bus driver */ | |
1da177e4 LT |
1964 | } else { |
1965 | msg[0].len = data->block[0] + 2; | |
1966 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
24a5bb7b DB |
1967 | dev_err(&adapter->dev, |
1968 | "Invalid block write size %d\n", | |
1969 | data->block[0]); | |
1970 | return -EINVAL; | |
1da177e4 | 1971 | } |
5c50d188 | 1972 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
1973 | msgbuf0[i] = data->block[i-1]; |
1974 | } | |
1975 | break; | |
1976 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
1977 | num = 2; /* Another special case */ |
1978 | read_write = I2C_SMBUS_READ; | |
1979 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
24a5bb7b DB |
1980 | dev_err(&adapter->dev, |
1981 | "Invalid block write size %d\n", | |
209d27c3 | 1982 | data->block[0]); |
24a5bb7b | 1983 | return -EINVAL; |
209d27c3 JD |
1984 | } |
1985 | msg[0].len = data->block[0] + 2; | |
1986 | for (i = 1; i < msg[0].len; i++) | |
1987 | msgbuf0[i] = data->block[i-1]; | |
1988 | msg[1].flags |= I2C_M_RECV_LEN; | |
1989 | msg[1].len = 1; /* block length will be added by | |
1990 | the underlying bus driver */ | |
1991 | break; | |
1da177e4 LT |
1992 | case I2C_SMBUS_I2C_BLOCK_DATA: |
1993 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 1994 | msg[1].len = data->block[0]; |
1da177e4 LT |
1995 | } else { |
1996 | msg[0].len = data->block[0] + 1; | |
30dac746 | 1997 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
24a5bb7b DB |
1998 | dev_err(&adapter->dev, |
1999 | "Invalid block write size %d\n", | |
2000 | data->block[0]); | |
2001 | return -EINVAL; | |
1da177e4 LT |
2002 | } |
2003 | for (i = 1; i <= data->block[0]; i++) | |
2004 | msgbuf0[i] = data->block[i]; | |
2005 | } | |
2006 | break; | |
2007 | default: | |
24a5bb7b DB |
2008 | dev_err(&adapter->dev, "Unsupported transaction %d\n", size); |
2009 | return -EOPNOTSUPP; | |
1da177e4 LT |
2010 | } |
2011 | ||
421ef47b JD |
2012 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
2013 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
2014 | if (i) { | |
2015 | /* Compute PEC if first message is a write */ | |
2016 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 2017 | if (num == 1) /* Write only */ |
421ef47b JD |
2018 | i2c_smbus_add_pec(&msg[0]); |
2019 | else /* Write followed by read */ | |
2020 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
2021 | } | |
2022 | /* Ask for PEC if last message is a read */ | |
2023 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 2024 | msg[num-1].len++; |
421ef47b JD |
2025 | } |
2026 | ||
24a5bb7b DB |
2027 | status = i2c_transfer(adapter, msg, num); |
2028 | if (status < 0) | |
2029 | return status; | |
1da177e4 | 2030 | |
421ef47b JD |
2031 | /* Check PEC if last message is a read */ |
2032 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
24a5bb7b DB |
2033 | status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); |
2034 | if (status < 0) | |
2035 | return status; | |
421ef47b JD |
2036 | } |
2037 | ||
1da177e4 | 2038 | if (read_write == I2C_SMBUS_READ) |
7225acf4 FH |
2039 | switch (size) { |
2040 | case I2C_SMBUS_BYTE: | |
2041 | data->byte = msgbuf0[0]; | |
2042 | break; | |
2043 | case I2C_SMBUS_BYTE_DATA: | |
2044 | data->byte = msgbuf1[0]; | |
2045 | break; | |
2046 | case I2C_SMBUS_WORD_DATA: | |
2047 | case I2C_SMBUS_PROC_CALL: | |
2048 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
2049 | break; | |
2050 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
2051 | for (i = 0; i < data->block[0]; i++) | |
2052 | data->block[i+1] = msgbuf1[i]; | |
2053 | break; | |
2054 | case I2C_SMBUS_BLOCK_DATA: | |
2055 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
2056 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
2057 | data->block[i] = msgbuf1[i]; | |
2058 | break; | |
1da177e4 LT |
2059 | } |
2060 | return 0; | |
2061 | } | |
2062 | ||
a1cdedac DB |
2063 | /** |
2064 | * i2c_smbus_xfer - execute SMBus protocol operations | |
2065 | * @adapter: Handle to I2C bus | |
2066 | * @addr: Address of SMBus slave on that bus | |
2067 | * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) | |
2068 | * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE | |
2069 | * @command: Byte interpreted by slave, for protocols which use such bytes | |
2070 | * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL | |
2071 | * @data: Data to be read or written | |
2072 | * | |
2073 | * This executes an SMBus protocol operation, and returns a negative | |
2074 | * errno code else zero on success. | |
2075 | */ | |
09b8ce0a | 2076 | s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, |
a1cdedac | 2077 | char read_write, u8 command, int protocol, |
09b8ce0a | 2078 | union i2c_smbus_data *data) |
1da177e4 | 2079 | { |
66b650f0 CW |
2080 | unsigned long orig_jiffies; |
2081 | int try; | |
1da177e4 | 2082 | s32 res; |
1da177e4 LT |
2083 | |
2084 | flags &= I2C_M_TEN | I2C_CLIENT_PEC; | |
1da177e4 LT |
2085 | |
2086 | if (adapter->algo->smbus_xfer) { | |
fe61e07e | 2087 | i2c_lock_adapter(adapter); |
66b650f0 CW |
2088 | |
2089 | /* Retry automatically on arbitration loss */ | |
2090 | orig_jiffies = jiffies; | |
2091 | for (res = 0, try = 0; try <= adapter->retries; try++) { | |
2092 | res = adapter->algo->smbus_xfer(adapter, addr, flags, | |
2093 | read_write, command, | |
2094 | protocol, data); | |
2095 | if (res != -EAGAIN) | |
2096 | break; | |
2097 | if (time_after(jiffies, | |
2098 | orig_jiffies + adapter->timeout)) | |
2099 | break; | |
2100 | } | |
fe61e07e | 2101 | i2c_unlock_adapter(adapter); |
1da177e4 | 2102 | } else |
7225acf4 | 2103 | res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, |
a1cdedac | 2104 | command, protocol, data); |
1da177e4 | 2105 | |
1da177e4 LT |
2106 | return res; |
2107 | } | |
1da177e4 | 2108 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 LT |
2109 | |
2110 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); | |
2111 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
2112 | MODULE_LICENSE("GPL"); |