]>
Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* ------------------------------------------------------------------------- */ |
438d6c2c | 2 | /* */ |
1da177e4 | 3 | /* i2c.h - definitions for the i2c-bus interface */ |
438d6c2c | 4 | /* */ |
1da177e4 LT |
5 | /* ------------------------------------------------------------------------- */ |
6 | /* Copyright (C) 1995-2000 Simon G. Vogl | |
7 | ||
8 | This program is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 2 of the License, or | |
11 | (at your option) any later version. | |
12 | ||
13 | This program is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with this program; if not, write to the Free Software | |
5694f8a8 JD |
20 | Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, |
21 | MA 02110-1301 USA. */ | |
1da177e4 LT |
22 | /* ------------------------------------------------------------------------- */ |
23 | ||
a1b9298e | 24 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and |
1da177e4 | 25 | Frodo Looijaard <frodol@dds.nl> */ |
1da177e4 LT |
26 | #ifndef _LINUX_I2C_H |
27 | #define _LINUX_I2C_H | |
28 | ||
a9d1b24d | 29 | #include <linux/mod_devicetable.h> |
1da177e4 | 30 | #include <linux/device.h> /* for struct device */ |
4e57b681 | 31 | #include <linux/sched.h> /* for completion */ |
5c085d36 | 32 | #include <linux/mutex.h> |
4d5538f5 | 33 | #include <linux/irqdomain.h> /* for Host Notify IRQ */ |
d12d42f7 | 34 | #include <linux/of.h> /* for struct device_node */ |
06a67848 | 35 | #include <linux/swab.h> /* for swab16 */ |
607ca46e | 36 | #include <uapi/linux/i2c.h> |
1da177e4 | 37 | |
e9ca9eb9 | 38 | extern struct bus_type i2c_bus_type; |
0826374b | 39 | extern struct device_type i2c_adapter_type; |
e9ca9eb9 | 40 | |
1da177e4 LT |
41 | /* --- General options ------------------------------------------------ */ |
42 | ||
43 | struct i2c_msg; | |
44 | struct i2c_algorithm; | |
45 | struct i2c_adapter; | |
46 | struct i2c_client; | |
47 | struct i2c_driver; | |
1da177e4 | 48 | union i2c_smbus_data; |
4735c98f | 49 | struct i2c_board_info; |
4b1acc43 WS |
50 | enum i2c_slave_event; |
51 | typedef int (*i2c_slave_cb_t)(struct i2c_client *, enum i2c_slave_event, u8 *); | |
1da177e4 | 52 | |
de477254 | 53 | struct module; |
d3e1b617 | 54 | struct property_entry; |
de477254 | 55 | |
23af8400 | 56 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
1da177e4 LT |
57 | /* |
58 | * The master routines are the ones normally used to transmit data to devices | |
438d6c2c DB |
59 | * on a bus (or read from them). Apart from two basic transfer functions to |
60 | * transmit one message at a time, a more complex version can be used to | |
1da177e4 | 61 | * transmit an arbitrary number of messages without interruption. |
0c43ea54 | 62 | * @count must be be less than 64k since msg.len is u16. |
1da177e4 | 63 | */ |
0cc43a18 JD |
64 | extern int i2c_master_send(const struct i2c_client *client, const char *buf, |
65 | int count); | |
66 | extern int i2c_master_recv(const struct i2c_client *client, char *buf, | |
3ae70dee | 67 | int count); |
1da177e4 LT |
68 | |
69 | /* Transfer num messages. | |
70 | */ | |
3ae70dee JD |
71 | extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, |
72 | int num); | |
b37d2a3a JD |
73 | /* Unlocked flavor */ |
74 | extern int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, | |
75 | int num); | |
1da177e4 LT |
76 | |
77 | /* This is the very generalized SMBus access routine. You probably do not | |
78 | want to use this, though; one of the functions below may be much easier, | |
438d6c2c | 79 | and probably just as fast. |
1da177e4 LT |
80 | Note that we use i2c_adapter here, because you do not need a specific |
81 | smbus adapter to call this function. */ | |
3ae70dee JD |
82 | extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, |
83 | unsigned short flags, char read_write, u8 command, | |
84 | int size, union i2c_smbus_data *data); | |
1da177e4 LT |
85 | |
86 | /* Now follow the 'nice' access routines. These also document the calling | |
ae7193f7 | 87 | conventions of i2c_smbus_xfer. */ |
1da177e4 | 88 | |
0cc43a18 JD |
89 | extern s32 i2c_smbus_read_byte(const struct i2c_client *client); |
90 | extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value); | |
91 | extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client, | |
92 | u8 command); | |
93 | extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client, | |
3ae70dee | 94 | u8 command, u8 value); |
0cc43a18 JD |
95 | extern s32 i2c_smbus_read_word_data(const struct i2c_client *client, |
96 | u8 command); | |
97 | extern s32 i2c_smbus_write_word_data(const struct i2c_client *client, | |
3ae70dee | 98 | u8 command, u16 value); |
06a67848 JC |
99 | |
100 | static inline s32 | |
101 | i2c_smbus_read_word_swapped(const struct i2c_client *client, u8 command) | |
102 | { | |
103 | s32 value = i2c_smbus_read_word_data(client, command); | |
104 | ||
105 | return (value < 0) ? value : swab16(value); | |
106 | } | |
107 | ||
108 | static inline s32 | |
109 | i2c_smbus_write_word_swapped(const struct i2c_client *client, | |
110 | u8 command, u16 value) | |
111 | { | |
112 | return i2c_smbus_write_word_data(client, command, swab16(value)); | |
113 | } | |
114 | ||
b86a1bc8 | 115 | /* Returns the number of read bytes */ |
0cc43a18 | 116 | extern s32 i2c_smbus_read_block_data(const struct i2c_client *client, |
b86a1bc8 | 117 | u8 command, u8 *values); |
0cc43a18 | 118 | extern s32 i2c_smbus_write_block_data(const struct i2c_client *client, |
3ae70dee | 119 | u8 command, u8 length, const u8 *values); |
31ec5bc5 | 120 | /* Returns the number of read bytes */ |
0cc43a18 | 121 | extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, |
4b2643d7 | 122 | u8 command, u8 length, u8 *values); |
0cc43a18 | 123 | extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, |
21bbd691 | 124 | u8 command, u8 length, |
46f5ed75 | 125 | const u8 *values); |
01eef96e IT |
126 | extern s32 |
127 | i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, | |
128 | u8 command, u8 length, u8 *values); | |
23af8400 | 129 | #endif /* I2C */ |
1da177e4 | 130 | |
b4f21054 BT |
131 | enum i2c_alert_protocol { |
132 | I2C_PROTOCOL_SMBUS_ALERT, | |
e456cd37 | 133 | I2C_PROTOCOL_SMBUS_HOST_NOTIFY, |
b4f21054 BT |
134 | }; |
135 | ||
4735c98f JD |
136 | /** |
137 | * struct i2c_driver - represent an I2C device driver | |
138 | * @class: What kind of i2c device we instantiate (for detect) | |
fe6fc258 | 139 | * @attach_adapter: Callback for bus addition (deprecated) |
b8a1a4cd LJ |
140 | * @probe: Callback for device binding - soon to be deprecated |
141 | * @probe_new: New callback for device binding | |
729d6dd5 | 142 | * @remove: Callback for device unbinding |
96e21e4f | 143 | * @shutdown: Callback for device shutdown |
72d2e9f9 | 144 | * @alert: Alert callback, for example for the SMBus alert protocol |
96e21e4f JD |
145 | * @command: Callback for bus-wide signaling (optional) |
146 | * @driver: Device driver model driver | |
147 | * @id_table: List of I2C devices supported by this driver | |
4735c98f | 148 | * @detect: Callback for device detection |
c3813d6a | 149 | * @address_list: The I2C addresses to probe (for detect) |
4735c98f | 150 | * @clients: List of detected clients we created (for i2c-core use only) |
35d8b2e6 LR |
151 | * |
152 | * The driver.owner field should be set to the module owner of this driver. | |
153 | * The driver.name field should be set to the name of this driver. | |
4735c98f | 154 | * |
0ec13867 | 155 | * For automatic device detection, both @detect and @address_list must |
4735c98f JD |
156 | * be defined. @class should also be set, otherwise only devices forced |
157 | * with module parameters will be created. The detect function must | |
158 | * fill at least the name field of the i2c_board_info structure it is | |
159 | * handed upon successful detection, and possibly also the flags field. | |
160 | * | |
161 | * If @detect is missing, the driver will still work fine for enumerated | |
162 | * devices. Detected devices simply won't be supported. This is expected | |
163 | * for the many I2C/SMBus devices which can't be detected reliably, and | |
164 | * the ones which can always be enumerated in practice. | |
165 | * | |
166 | * The i2c_client structure which is handed to the @detect callback is | |
167 | * not a real i2c_client. It is initialized just enough so that you can | |
168 | * call i2c_smbus_read_byte_data and friends on it. Don't do anything | |
169 | * else with it. In particular, calling dev_dbg and friends on it is | |
170 | * not allowed. | |
1da177e4 | 171 | */ |
1da177e4 | 172 | struct i2c_driver { |
1da177e4 | 173 | unsigned int class; |
1da177e4 | 174 | |
19baba4c LPC |
175 | /* Notifies the driver that a new bus has appeared. You should avoid |
176 | * using this, it will be removed in a near future. | |
1da177e4 | 177 | */ |
fe6fc258 | 178 | int (*attach_adapter)(struct i2c_adapter *) __deprecated; |
1da177e4 | 179 | |
729d6dd5 | 180 | /* Standard driver model interfaces */ |
d2653e92 | 181 | int (*probe)(struct i2c_client *, const struct i2c_device_id *); |
a1d9e6e4 | 182 | int (*remove)(struct i2c_client *); |
7b4fbc50 | 183 | |
b8a1a4cd LJ |
184 | /* New driver model interface to aid the seamless removal of the |
185 | * current probe()'s, more commonly unused than used second parameter. | |
186 | */ | |
187 | int (*probe_new)(struct i2c_client *); | |
188 | ||
f37dd80a DB |
189 | /* driver model interfaces that don't relate to enumeration */ |
190 | void (*shutdown)(struct i2c_client *); | |
f37dd80a | 191 | |
b5527a77 JD |
192 | /* Alert callback, for example for the SMBus alert protocol. |
193 | * The format and meaning of the data value depends on the protocol. | |
194 | * For the SMBus alert protocol, there is a single bit of data passed | |
195 | * as the alert response's low bit ("event flag"). | |
e456cd37 BT |
196 | * For the SMBus Host Notify protocol, the data corresponds to the |
197 | * 16-bit payload data reported by the slave device acting as master. | |
b5527a77 | 198 | */ |
b4f21054 BT |
199 | void (*alert)(struct i2c_client *, enum i2c_alert_protocol protocol, |
200 | unsigned int data); | |
b5527a77 | 201 | |
1da177e4 LT |
202 | /* a ioctl like command that can be used to perform specific functions |
203 | * with the device. | |
204 | */ | |
3ae70dee | 205 | int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); |
1da177e4 LT |
206 | |
207 | struct device_driver driver; | |
d2653e92 | 208 | const struct i2c_device_id *id_table; |
4735c98f JD |
209 | |
210 | /* Device detection callback for automatic device creation */ | |
310ec792 | 211 | int (*detect)(struct i2c_client *, struct i2c_board_info *); |
c3813d6a | 212 | const unsigned short *address_list; |
4735c98f | 213 | struct list_head clients; |
1da177e4 LT |
214 | }; |
215 | #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) | |
216 | ||
2096b956 DB |
217 | /** |
218 | * struct i2c_client - represent an I2C slave device | |
d64f73be DB |
219 | * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address; |
220 | * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking | |
2096b956 DB |
221 | * @addr: Address used on the I2C bus connected to the parent adapter. |
222 | * @name: Indicates the type of the device, usually a chip name that's | |
223 | * generic enough to hide second-sourcing and compatible revisions. | |
d64f73be | 224 | * @adapter: manages the bus segment hosting this I2C device |
2096b956 | 225 | * @dev: Driver model device node for the slave. |
d64f73be | 226 | * @irq: indicates the IRQ generated by this device (if any) |
99cd8e25 JD |
227 | * @detected: member of an i2c_driver.clients list or i2c-core's |
228 | * userspace_devices list | |
4b1acc43 WS |
229 | * @slave_cb: Callback when I2C slave mode of an adapter is used. The adapter |
230 | * calls it to pass on slave events to the slave driver. | |
2096b956 DB |
231 | * |
232 | * An i2c_client identifies a single device (i.e. chip) connected to an | |
d64f73be DB |
233 | * i2c bus. The behaviour exposed to Linux is defined by the driver |
234 | * managing the device. | |
1da177e4 LT |
235 | */ |
236 | struct i2c_client { | |
2096b956 | 237 | unsigned short flags; /* div., see below */ |
438d6c2c | 238 | unsigned short addr; /* chip address - NOTE: 7bit */ |
1da177e4 | 239 | /* addresses are stored in the */ |
5071860a | 240 | /* _LOWER_ 7 bits */ |
2096b956 | 241 | char name[I2C_NAME_SIZE]; |
1da177e4 | 242 | struct i2c_adapter *adapter; /* the adapter we sit on */ |
1da177e4 | 243 | struct device dev; /* the device structure */ |
8e29da9e | 244 | int irq; /* irq issued by device */ |
4735c98f | 245 | struct list_head detected; |
d5fd120e | 246 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 | 247 | i2c_slave_cb_t slave_cb; /* callback for slave mode */ |
d5fd120e | 248 | #endif |
1da177e4 LT |
249 | }; |
250 | #define to_i2c_client(d) container_of(d, struct i2c_client, dev) | |
251 | ||
9b766b81 | 252 | extern struct i2c_client *i2c_verify_client(struct device *dev); |
643dd09e | 253 | extern struct i2c_adapter *i2c_verify_adapter(struct device *dev); |
5f441fca LJ |
254 | extern const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
255 | const struct i2c_client *client); | |
9b766b81 | 256 | |
a61fc683 BG |
257 | static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj) |
258 | { | |
d75d53cd MH |
259 | struct device * const dev = container_of(kobj, struct device, kobj); |
260 | return to_i2c_client(dev); | |
a61fc683 BG |
261 | } |
262 | ||
7d1d8999 | 263 | static inline void *i2c_get_clientdata(const struct i2c_client *dev) |
1da177e4 | 264 | { |
3ae70dee | 265 | return dev_get_drvdata(&dev->dev); |
1da177e4 LT |
266 | } |
267 | ||
3ae70dee | 268 | static inline void i2c_set_clientdata(struct i2c_client *dev, void *data) |
1da177e4 | 269 | { |
3ae70dee | 270 | dev_set_drvdata(&dev->dev, data); |
1da177e4 LT |
271 | } |
272 | ||
4b1acc43 WS |
273 | /* I2C slave support */ |
274 | ||
d5fd120e | 275 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 | 276 | enum i2c_slave_event { |
5b77d162 WS |
277 | I2C_SLAVE_READ_REQUESTED, |
278 | I2C_SLAVE_WRITE_REQUESTED, | |
279 | I2C_SLAVE_READ_PROCESSED, | |
280 | I2C_SLAVE_WRITE_RECEIVED, | |
4b1acc43 WS |
281 | I2C_SLAVE_STOP, |
282 | }; | |
283 | ||
284 | extern int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb); | |
285 | extern int i2c_slave_unregister(struct i2c_client *client); | |
286 | ||
287 | static inline int i2c_slave_event(struct i2c_client *client, | |
288 | enum i2c_slave_event event, u8 *val) | |
289 | { | |
290 | return client->slave_cb(client, event, val); | |
291 | } | |
d5fd120e | 292 | #endif |
4b1acc43 | 293 | |
9c1600ed DB |
294 | /** |
295 | * struct i2c_board_info - template for device creation | |
eb8a7908 | 296 | * @type: chip type, to initialize i2c_client.name |
9c1600ed DB |
297 | * @flags: to initialize i2c_client.flags |
298 | * @addr: stored in i2c_client.addr | |
299 | * @platform_data: stored in i2c_client.dev.platform_data | |
11f1f2af | 300 | * @archdata: copied into i2c_client.dev.archdata |
72d2e9f9 | 301 | * @of_node: pointer to OpenFirmware device node |
ce793486 | 302 | * @fwnode: device node supplied by the platform firmware |
d3e1b617 | 303 | * @properties: additional device properties for the device |
9c1600ed | 304 | * @irq: stored in i2c_client.irq |
d64f73be | 305 | * |
9c1600ed DB |
306 | * I2C doesn't actually support hardware probing, although controllers and |
307 | * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's | |
308 | * a device at a given address. Drivers commonly need more information than | |
309 | * that, such as chip type, configuration, associated IRQ, and so on. | |
310 | * | |
311 | * i2c_board_info is used to build tables of information listing I2C devices | |
729d6dd5 JD |
312 | * that are present. This information is used to grow the driver model tree. |
313 | * For mainboards this is done statically using i2c_register_board_info(); | |
314 | * bus numbers identify adapters that aren't yet available. For add-on boards, | |
315 | * i2c_new_device() does this dynamically with the adapter already known. | |
9c1600ed DB |
316 | */ |
317 | struct i2c_board_info { | |
9c1600ed DB |
318 | char type[I2C_NAME_SIZE]; |
319 | unsigned short flags; | |
320 | unsigned short addr; | |
321 | void *platform_data; | |
11f1f2af | 322 | struct dev_archdata *archdata; |
d12d42f7 | 323 | struct device_node *of_node; |
ce793486 | 324 | struct fwnode_handle *fwnode; |
d3e1b617 | 325 | const struct property_entry *properties; |
9c1600ed DB |
326 | int irq; |
327 | }; | |
328 | ||
329 | /** | |
3760f736 JD |
330 | * I2C_BOARD_INFO - macro used to list an i2c device and its address |
331 | * @dev_type: identifies the device type | |
9c1600ed DB |
332 | * @dev_addr: the device's address on the bus. |
333 | * | |
334 | * This macro initializes essential fields of a struct i2c_board_info, | |
335 | * declaring what has been provided on a particular board. Optional | |
3760f736 JD |
336 | * fields (such as associated irq, or device-specific platform_data) |
337 | * are provided using conventional syntax. | |
9c1600ed | 338 | */ |
3ae70dee | 339 | #define I2C_BOARD_INFO(dev_type, dev_addr) \ |
c758e8cf | 340 | .type = dev_type, .addr = (dev_addr) |
9c1600ed DB |
341 | |
342 | ||
23af8400 | 343 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
9c1600ed DB |
344 | /* Add-on boards should register/unregister their devices; e.g. a board |
345 | * with integrated I2C, a config eeprom, sensors, and a codec that's | |
346 | * used in conjunction with the primary hardware. | |
347 | */ | |
348 | extern struct i2c_client * | |
349 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info); | |
350 | ||
12b5053a JD |
351 | /* If you don't know the exact address of an I2C device, use this variant |
352 | * instead, which can probe for device presence in a list of possible | |
9a94241a JD |
353 | * addresses. The "probe" callback function is optional. If it is provided, |
354 | * it must return 1 on successful probe, 0 otherwise. If it is not provided, | |
355 | * a default probing method is used. | |
12b5053a JD |
356 | */ |
357 | extern struct i2c_client * | |
358 | i2c_new_probed_device(struct i2c_adapter *adap, | |
359 | struct i2c_board_info *info, | |
9a94241a JD |
360 | unsigned short const *addr_list, |
361 | int (*probe)(struct i2c_adapter *, unsigned short addr)); | |
12b5053a | 362 | |
d44f19d5 JD |
363 | /* Common custom probe functions */ |
364 | extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); | |
365 | ||
e9f1373b DB |
366 | /* For devices that use several addresses, use i2c_new_dummy() to make |
367 | * client handles for the extra addresses. | |
368 | */ | |
369 | extern struct i2c_client * | |
60b129d7 | 370 | i2c_new_dummy(struct i2c_adapter *adap, u16 address); |
e9f1373b | 371 | |
0f614d83 JMH |
372 | extern struct i2c_client * |
373 | i2c_new_secondary_device(struct i2c_client *client, | |
374 | const char *name, | |
375 | u16 default_addr); | |
376 | ||
9c1600ed | 377 | extern void i2c_unregister_device(struct i2c_client *); |
23af8400 | 378 | #endif /* I2C */ |
9c1600ed DB |
379 | |
380 | /* Mainboard arch_initcall() code should register all its I2C devices. | |
381 | * This is done at arch_initcall time, before declaring any i2c adapters. | |
382 | * Modules for add-on boards must use other calls. | |
383 | */ | |
26386763 | 384 | #ifdef CONFIG_I2C_BOARDINFO |
9c1600ed | 385 | extern int |
3ae70dee JD |
386 | i2c_register_board_info(int busnum, struct i2c_board_info const *info, |
387 | unsigned n); | |
26386763 DB |
388 | #else |
389 | static inline int | |
3ae70dee JD |
390 | i2c_register_board_info(int busnum, struct i2c_board_info const *info, |
391 | unsigned n) | |
26386763 DB |
392 | { |
393 | return 0; | |
394 | } | |
23af8400 | 395 | #endif /* I2C_BOARDINFO */ |
9c1600ed | 396 | |
25ee33fb BD |
397 | /** |
398 | * struct i2c_algorithm - represent I2C transfer method | |
399 | * @master_xfer: Issue a set of i2c transactions to the given I2C adapter | |
400 | * defined by the msgs array, with num messages available to transfer via | |
401 | * the adapter specified by adap. | |
402 | * @smbus_xfer: Issue smbus transactions to the given I2C adapter. If this | |
403 | * is not present, then the bus layer will try and convert the SMBus calls | |
404 | * into I2C transfers instead. | |
405 | * @functionality: Return the flags that this algorithm/adapter pair supports | |
406 | * from the I2C_FUNC_* flags. | |
4b1acc43 WS |
407 | * @reg_slave: Register given client to I2C slave mode of this adapter |
408 | * @unreg_slave: Unregister given client from I2C slave mode of this adapter | |
25ee33fb | 409 | * |
1da177e4 LT |
410 | * The following structs are for those who like to implement new bus drivers: |
411 | * i2c_algorithm is the interface to a class of hardware solutions which can | |
412 | * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584 | |
413 | * to name two of the most common. | |
25ee33fb BD |
414 | * |
415 | * The return codes from the @master_xfer field should indicate the type of | |
f353d71f | 416 | * error code that occurred during the transfer, as documented in the kernel |
25ee33fb | 417 | * Documentation file Documentation/i2c/fault-codes. |
1da177e4 LT |
418 | */ |
419 | struct i2c_algorithm { | |
1da177e4 | 420 | /* If an adapter algorithm can't do I2C-level access, set master_xfer |
438d6c2c | 421 | to NULL. If an adapter algorithm can do SMBus access, set |
1da177e4 LT |
422 | smbus_xfer. If set to NULL, the SMBus protocol is simulated |
423 | using common I2C messages */ | |
8ced8eee JD |
424 | /* master_xfer should return the number of messages successfully |
425 | processed, or a negative value on error */ | |
3ae70dee JD |
426 | int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, |
427 | int num); | |
438d6c2c | 428 | int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr, |
3ae70dee JD |
429 | unsigned short flags, char read_write, |
430 | u8 command, int size, union i2c_smbus_data *data); | |
1da177e4 | 431 | |
1da177e4 LT |
432 | /* To determine what the adapter supports */ |
433 | u32 (*functionality) (struct i2c_adapter *); | |
4b1acc43 | 434 | |
d5fd120e | 435 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 WS |
436 | int (*reg_slave)(struct i2c_client *client); |
437 | int (*unreg_slave)(struct i2c_client *client); | |
d5fd120e | 438 | #endif |
1da177e4 LT |
439 | }; |
440 | ||
d1ed7985 PR |
441 | /** |
442 | * struct i2c_lock_operations - represent I2C locking operations | |
443 | * @lock_bus: Get exclusive access to an I2C bus segment | |
444 | * @trylock_bus: Try to get exclusive access to an I2C bus segment | |
445 | * @unlock_bus: Release exclusive access to an I2C bus segment | |
446 | * | |
447 | * The main operations are wrapped by i2c_lock_bus and i2c_unlock_bus. | |
448 | */ | |
449 | struct i2c_lock_operations { | |
450 | void (*lock_bus)(struct i2c_adapter *, unsigned int flags); | |
451 | int (*trylock_bus)(struct i2c_adapter *, unsigned int flags); | |
452 | void (*unlock_bus)(struct i2c_adapter *, unsigned int flags); | |
453 | }; | |
454 | ||
e1dba01c WS |
455 | /** |
456 | * struct i2c_timings - I2C timing information | |
457 | * @bus_freq_hz: the bus frequency in Hz | |
458 | * @scl_rise_ns: time SCL signal takes to rise in ns; t(r) in the I2C specification | |
459 | * @scl_fall_ns: time SCL signal takes to fall in ns; t(f) in the I2C specification | |
460 | * @scl_int_delay_ns: time IP core additionally needs to setup SCL in ns | |
461 | * @sda_fall_ns: time SDA signal takes to fall in ns; t(f) in the I2C specification | |
462 | */ | |
463 | struct i2c_timings { | |
464 | u32 bus_freq_hz; | |
465 | u32 scl_rise_ns; | |
466 | u32 scl_fall_ns; | |
467 | u32 scl_int_delay_ns; | |
468 | u32 sda_fall_ns; | |
469 | }; | |
470 | ||
5f9296ba VK |
471 | /** |
472 | * struct i2c_bus_recovery_info - I2C bus recovery information | |
473 | * @recover_bus: Recover routine. Either pass driver's recover_bus() routine, or | |
474 | * i2c_generic_scl_recovery() or i2c_generic_gpio_recovery(). | |
475 | * @get_scl: This gets current value of SCL line. Mandatory for generic SCL | |
476 | * recovery. Used internally for generic GPIO recovery. | |
477 | * @set_scl: This sets/clears SCL line. Mandatory for generic SCL recovery. Used | |
478 | * internally for generic GPIO recovery. | |
479 | * @get_sda: This gets current value of SDA line. Optional for generic SCL | |
480 | * recovery. Used internally, if sda_gpio is a valid GPIO, for generic GPIO | |
481 | * recovery. | |
482 | * @prepare_recovery: This will be called before starting recovery. Platform may | |
483 | * configure padmux here for SDA/SCL line or something else they want. | |
484 | * @unprepare_recovery: This will be called after completing recovery. Platform | |
485 | * may configure padmux here for SDA/SCL line or something else they want. | |
486 | * @scl_gpio: gpio number of the SCL line. Only required for GPIO recovery. | |
487 | * @sda_gpio: gpio number of the SDA line. Only required for GPIO recovery. | |
488 | */ | |
489 | struct i2c_bus_recovery_info { | |
490 | int (*recover_bus)(struct i2c_adapter *); | |
491 | ||
492 | int (*get_scl)(struct i2c_adapter *); | |
493 | void (*set_scl)(struct i2c_adapter *, int val); | |
494 | int (*get_sda)(struct i2c_adapter *); | |
495 | ||
2b2190a3 GS |
496 | void (*prepare_recovery)(struct i2c_adapter *); |
497 | void (*unprepare_recovery)(struct i2c_adapter *); | |
5f9296ba VK |
498 | |
499 | /* gpio recovery */ | |
500 | int scl_gpio; | |
501 | int sda_gpio; | |
502 | }; | |
503 | ||
504 | int i2c_recover_bus(struct i2c_adapter *adap); | |
505 | ||
506 | /* Generic recovery routines */ | |
507 | int i2c_generic_gpio_recovery(struct i2c_adapter *adap); | |
508 | int i2c_generic_scl_recovery(struct i2c_adapter *adap); | |
509 | ||
2187f03a WS |
510 | /** |
511 | * struct i2c_adapter_quirks - describe flaws of an i2c adapter | |
512 | * @flags: see I2C_AQ_* for possible flags and read below | |
513 | * @max_num_msgs: maximum number of messages per transfer | |
514 | * @max_write_len: maximum length of a write message | |
515 | * @max_read_len: maximum length of a read message | |
516 | * @max_comb_1st_msg_len: maximum length of the first msg in a combined message | |
517 | * @max_comb_2nd_msg_len: maximum length of the second msg in a combined message | |
518 | * | |
519 | * Note about combined messages: Some I2C controllers can only send one message | |
520 | * per transfer, plus something called combined message or write-then-read. | |
521 | * This is (usually) a small write message followed by a read message and | |
522 | * barely enough to access register based devices like EEPROMs. There is a flag | |
523 | * to support this mode. It implies max_num_msg = 2 and does the length checks | |
524 | * with max_comb_*_len because combined message mode usually has its own | |
525 | * limitations. Because of HW implementations, some controllers can actually do | |
526 | * write-then-anything or other variants. To support that, write-then-read has | |
527 | * been broken out into smaller bits like write-first and read-second which can | |
528 | * be combined as needed. | |
529 | */ | |
530 | ||
531 | struct i2c_adapter_quirks { | |
532 | u64 flags; | |
533 | int max_num_msgs; | |
534 | u16 max_write_len; | |
535 | u16 max_read_len; | |
536 | u16 max_comb_1st_msg_len; | |
537 | u16 max_comb_2nd_msg_len; | |
538 | }; | |
539 | ||
540 | /* enforce max_num_msgs = 2 and use max_comb_*_len for length checks */ | |
541 | #define I2C_AQ_COMB BIT(0) | |
542 | /* first combined message must be write */ | |
543 | #define I2C_AQ_COMB_WRITE_FIRST BIT(1) | |
544 | /* second combined message must be read */ | |
545 | #define I2C_AQ_COMB_READ_SECOND BIT(2) | |
546 | /* both combined messages must have the same target address */ | |
547 | #define I2C_AQ_COMB_SAME_ADDR BIT(3) | |
548 | /* convenience macro for typical write-then read case */ | |
549 | #define I2C_AQ_COMB_WRITE_THEN_READ (I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | \ | |
550 | I2C_AQ_COMB_READ_SECOND | I2C_AQ_COMB_SAME_ADDR) | |
749de3da NC |
551 | /* clock stretching is not supported */ |
552 | #define I2C_AQ_NO_CLK_STRETCH BIT(4) | |
2187f03a | 553 | |
1da177e4 LT |
554 | /* |
555 | * i2c_adapter is the structure used to identify a physical i2c bus along | |
556 | * with the access algorithms necessary to access it. | |
557 | */ | |
558 | struct i2c_adapter { | |
559 | struct module *owner; | |
14f55f7a | 560 | unsigned int class; /* classes to allow probing for */ |
af71ff69 | 561 | const struct i2c_algorithm *algo; /* the algorithm to access the bus */ |
1da177e4 LT |
562 | void *algo_data; |
563 | ||
1da177e4 | 564 | /* data fields that are valid for all devices */ |
d1ed7985 | 565 | const struct i2c_lock_operations *lock_ops; |
194684e5 | 566 | struct rt_mutex bus_lock; |
6ef91fcc | 567 | struct rt_mutex mux_lock; |
1da177e4 | 568 | |
cd97f39b | 569 | int timeout; /* in jiffies */ |
1da177e4 LT |
570 | int retries; |
571 | struct device dev; /* the adapter device */ | |
1da177e4 | 572 | |
1da177e4 | 573 | int nr; |
2096b956 | 574 | char name[48]; |
1da177e4 | 575 | struct completion dev_released; |
6629dcff | 576 | |
dafc50d1 | 577 | struct mutex userspace_clients_lock; |
6629dcff | 578 | struct list_head userspace_clients; |
5f9296ba VK |
579 | |
580 | struct i2c_bus_recovery_info *bus_recovery_info; | |
2187f03a | 581 | const struct i2c_adapter_quirks *quirks; |
4d5538f5 BT |
582 | |
583 | struct irq_domain *host_notify_domain; | |
1da177e4 | 584 | }; |
ef2c8321 | 585 | #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) |
1da177e4 | 586 | |
7d1d8999 | 587 | static inline void *i2c_get_adapdata(const struct i2c_adapter *dev) |
1da177e4 | 588 | { |
3ae70dee | 589 | return dev_get_drvdata(&dev->dev); |
1da177e4 LT |
590 | } |
591 | ||
3ae70dee | 592 | static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data) |
1da177e4 | 593 | { |
3ae70dee | 594 | dev_set_drvdata(&dev->dev, data); |
1da177e4 LT |
595 | } |
596 | ||
97cc4d49 JD |
597 | static inline struct i2c_adapter * |
598 | i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter) | |
0826374b | 599 | { |
2fac2b89 | 600 | #if IS_ENABLED(CONFIG_I2C_MUX) |
97cc4d49 JD |
601 | struct device *parent = adapter->dev.parent; |
602 | ||
603 | if (parent != NULL && parent->type == &i2c_adapter_type) | |
604 | return to_i2c_adapter(parent); | |
605 | else | |
3923172b | 606 | #endif |
97cc4d49 | 607 | return NULL; |
0826374b ML |
608 | } |
609 | ||
7ae31482 JD |
610 | int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)); |
611 | ||
fe61e07e | 612 | /* Adapter locking functions, exported for shared pin cases */ |
8320f495 PR |
613 | #define I2C_LOCK_ROOT_ADAPTER BIT(0) |
614 | #define I2C_LOCK_SEGMENT BIT(1) | |
615 | ||
616 | /** | |
617 | * i2c_lock_bus - Get exclusive access to an I2C bus segment | |
618 | * @adapter: Target I2C bus segment | |
619 | * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT | |
620 | * locks only this branch in the adapter tree | |
621 | */ | |
622 | static inline void | |
623 | i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags) | |
624 | { | |
d1ed7985 | 625 | adapter->lock_ops->lock_bus(adapter, flags); |
8320f495 PR |
626 | } |
627 | ||
fb79e09a PR |
628 | /** |
629 | * i2c_trylock_bus - Try to get exclusive access to an I2C bus segment | |
630 | * @adapter: Target I2C bus segment | |
631 | * @flags: I2C_LOCK_ROOT_ADAPTER tries to locks the root i2c adapter, | |
632 | * I2C_LOCK_SEGMENT tries to lock only this branch in the adapter tree | |
633 | * | |
634 | * Return: true if the I2C bus segment is locked, false otherwise | |
635 | */ | |
636 | static inline int | |
637 | i2c_trylock_bus(struct i2c_adapter *adapter, unsigned int flags) | |
638 | { | |
d1ed7985 | 639 | return adapter->lock_ops->trylock_bus(adapter, flags); |
fb79e09a PR |
640 | } |
641 | ||
8320f495 PR |
642 | /** |
643 | * i2c_unlock_bus - Release exclusive access to an I2C bus segment | |
644 | * @adapter: Target I2C bus segment | |
645 | * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT | |
646 | * unlocks only this branch in the adapter tree | |
647 | */ | |
648 | static inline void | |
649 | i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags) | |
650 | { | |
d1ed7985 | 651 | adapter->lock_ops->unlock_bus(adapter, flags); |
8320f495 PR |
652 | } |
653 | ||
654 | static inline void | |
655 | i2c_lock_adapter(struct i2c_adapter *adapter) | |
656 | { | |
657 | i2c_lock_bus(adapter, I2C_LOCK_ROOT_ADAPTER); | |
658 | } | |
659 | ||
660 | static inline void | |
661 | i2c_unlock_adapter(struct i2c_adapter *adapter) | |
662 | { | |
663 | i2c_unlock_bus(adapter, I2C_LOCK_ROOT_ADAPTER); | |
664 | } | |
afa08974 | 665 | |
1da177e4 | 666 | /*flags for the client struct: */ |
c5ebb387 WS |
667 | #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ |
668 | #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ | |
3bbb835d | 669 | /* Must equal I2C_M_TEN below */ |
c5ebb387 | 670 | #define I2C_CLIENT_SLAVE 0x20 /* we are the slave */ |
331c3425 | 671 | #define I2C_CLIENT_HOST_NOTIFY 0x40 /* We want to use I2C host notify */ |
c5ebb387 WS |
672 | #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */ |
673 | #define I2C_CLIENT_SCCB 0x9000 /* Use Omnivision SCCB protocol */ | |
d47726c5 | 674 | /* Must match I2C_M_STOP|IGNORE_NAK */ |
1da177e4 LT |
675 | |
676 | /* i2c adapter classes (bitmask) */ | |
677 | #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ | |
c1b6b4f2 | 678 | #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */ |
774466ad | 679 | #define I2C_CLASS_SPD (1<<7) /* Memory modules */ |
0c176170 | 680 | #define I2C_CLASS_DEPRECATED (1<<8) /* Warn users that adapter will stop using classes */ |
1da177e4 | 681 | |
1da177e4 LT |
682 | /* Internal numbers to terminate lists */ |
683 | #define I2C_CLIENT_END 0xfffeU | |
1da177e4 | 684 | |
c7036673 HV |
685 | /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */ |
686 | #define I2C_ADDRS(addr, addrs...) \ | |
687 | ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END }) | |
688 | ||
1da177e4 LT |
689 | |
690 | /* ----- functions exported by i2c.o */ | |
691 | ||
692 | /* administration... | |
693 | */ | |
23af8400 | 694 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
1da177e4 | 695 | extern int i2c_add_adapter(struct i2c_adapter *); |
71546300 | 696 | extern void i2c_del_adapter(struct i2c_adapter *); |
6e13e641 | 697 | extern int i2c_add_numbered_adapter(struct i2c_adapter *); |
1da177e4 | 698 | |
de59cf9e | 699 | extern int i2c_register_driver(struct module *, struct i2c_driver *); |
b3e82096 | 700 | extern void i2c_del_driver(struct i2c_driver *); |
1da177e4 | 701 | |
eb5589a8 PG |
702 | /* use a define to avoid include chaining to get THIS_MODULE */ |
703 | #define i2c_add_driver(driver) \ | |
704 | i2c_register_driver(THIS_MODULE, driver) | |
de59cf9e | 705 | |
e48d3319 JD |
706 | extern struct i2c_client *i2c_use_client(struct i2c_client *client); |
707 | extern void i2c_release_client(struct i2c_client *client); | |
1da177e4 LT |
708 | |
709 | /* call the i2c_client->command() of all attached clients with | |
710 | * the given arguments */ | |
711 | extern void i2c_clients_command(struct i2c_adapter *adap, | |
712 | unsigned int cmd, void *arg); | |
713 | ||
d735b34d | 714 | extern struct i2c_adapter *i2c_get_adapter(int nr); |
1da177e4 | 715 | extern void i2c_put_adapter(struct i2c_adapter *adap); |
8dd1fe15 | 716 | extern unsigned int i2c_adapter_depth(struct i2c_adapter *adapter); |
1da177e4 | 717 | |
e1dba01c | 718 | void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults); |
1da177e4 LT |
719 | |
720 | /* Return the functionality mask */ | |
721 | static inline u32 i2c_get_functionality(struct i2c_adapter *adap) | |
722 | { | |
723 | return adap->algo->functionality(adap); | |
724 | } | |
725 | ||
726 | /* Return 1 if adapter supports everything we need, 0 if not. */ | |
727 | static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func) | |
728 | { | |
729 | return (func & i2c_get_functionality(adap)) == func; | |
730 | } | |
731 | ||
cfa576db NC |
732 | /** |
733 | * i2c_check_quirks() - Function for checking the quirk flags in an i2c adapter | |
734 | * @adap: i2c adapter | |
735 | * @quirks: quirk flags | |
736 | * | |
737 | * Return: true if the adapter has all the specified quirk flags, false if not | |
738 | */ | |
739 | static inline bool i2c_check_quirks(struct i2c_adapter *adap, u64 quirks) | |
740 | { | |
741 | if (!adap->quirks) | |
742 | return false; | |
743 | return (adap->quirks->flags & quirks) == quirks; | |
744 | } | |
745 | ||
3ae70dee | 746 | /* Return the adapter number for a specific adapter */ |
cdcb1921 JD |
747 | static inline int i2c_adapter_id(struct i2c_adapter *adap) |
748 | { | |
749 | return adap->nr; | |
750 | } | |
7c92784a | 751 | |
a16d6ebc WS |
752 | static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg) |
753 | { | |
754 | return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0); | |
755 | } | |
756 | ||
4d5538f5 | 757 | int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr); |
7c92784a | 758 | /** |
c698d639 | 759 | * module_i2c_driver() - Helper macro for registering a modular I2C driver |
7c92784a LPC |
760 | * @__i2c_driver: i2c_driver struct |
761 | * | |
762 | * Helper macro for I2C drivers which do not do anything special in module | |
763 | * init/exit. This eliminates a lot of boilerplate. Each module may only | |
764 | * use this macro once, and calling it replaces module_init() and module_exit() | |
765 | */ | |
766 | #define module_i2c_driver(__i2c_driver) \ | |
767 | module_driver(__i2c_driver, i2c_add_driver, \ | |
768 | i2c_del_driver) | |
769 | ||
c698d639 PG |
770 | /** |
771 | * builtin_i2c_driver() - Helper macro for registering a builtin I2C driver | |
772 | * @__i2c_driver: i2c_driver struct | |
773 | * | |
774 | * Helper macro for I2C drivers which do not do anything special in their | |
775 | * init. This eliminates a lot of boilerplate. Each driver may only | |
776 | * use this macro once, and calling it replaces device_initcall(). | |
777 | */ | |
778 | #define builtin_i2c_driver(__i2c_driver) \ | |
779 | builtin_driver(__i2c_driver, i2c_add_driver) | |
780 | ||
23af8400 | 781 | #endif /* I2C */ |
907ddf89 | 782 | |
687b81d0 WS |
783 | #if IS_ENABLED(CONFIG_OF) |
784 | /* must call put_device() when done with returned i2c_client device */ | |
785 | extern struct i2c_client *of_find_i2c_device_by_node(struct device_node *node); | |
786 | ||
787 | /* must call put_device() when done with returned i2c_adapter device */ | |
788 | extern struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node); | |
789 | ||
48e9743d VZ |
790 | /* must call i2c_put_adapter() when done with returned i2c_adapter device */ |
791 | struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node); | |
e1dba01c | 792 | |
298d4de1 LJ |
793 | extern const struct of_device_id |
794 | *i2c_of_match_device(const struct of_device_id *matches, | |
795 | struct i2c_client *client); | |
796 | ||
687b81d0 WS |
797 | #else |
798 | ||
799 | static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) | |
800 | { | |
801 | return NULL; | |
802 | } | |
803 | ||
804 | static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) | |
805 | { | |
806 | return NULL; | |
807 | } | |
48e9743d VZ |
808 | |
809 | static inline struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) | |
810 | { | |
811 | return NULL; | |
812 | } | |
298d4de1 LJ |
813 | |
814 | static inline const struct of_device_id | |
815 | *i2c_of_match_device(const struct of_device_id *matches, | |
816 | struct i2c_client *client) | |
817 | { | |
818 | return NULL; | |
819 | } | |
820 | ||
687b81d0 WS |
821 | #endif /* CONFIG_OF */ |
822 | ||
5853b22d JN |
823 | #if IS_ENABLED(CONFIG_ACPI) |
824 | u32 i2c_acpi_find_bus_speed(struct device *dev); | |
825 | #else | |
826 | static inline u32 i2c_acpi_find_bus_speed(struct device *dev) | |
827 | { | |
828 | return 0; | |
829 | } | |
830 | #endif /* CONFIG_ACPI */ | |
831 | ||
1da177e4 | 832 | #endif /* _LINUX_I2C_H */ |