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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> |
037741a6 | 33 | #include <linux/rtmutex.h> |
4d5538f5 | 34 | #include <linux/irqdomain.h> /* for Host Notify IRQ */ |
d12d42f7 | 35 | #include <linux/of.h> /* for struct device_node */ |
06a67848 | 36 | #include <linux/swab.h> /* for swab16 */ |
607ca46e | 37 | #include <uapi/linux/i2c.h> |
1da177e4 | 38 | |
e9ca9eb9 | 39 | extern struct bus_type i2c_bus_type; |
0826374b | 40 | extern struct device_type i2c_adapter_type; |
e9ca9eb9 | 41 | |
1da177e4 LT |
42 | /* --- General options ------------------------------------------------ */ |
43 | ||
44 | struct i2c_msg; | |
45 | struct i2c_algorithm; | |
46 | struct i2c_adapter; | |
47 | struct i2c_client; | |
48 | struct i2c_driver; | |
1da177e4 | 49 | union i2c_smbus_data; |
4735c98f | 50 | struct i2c_board_info; |
4b1acc43 WS |
51 | enum i2c_slave_event; |
52 | typedef int (*i2c_slave_cb_t)(struct i2c_client *, enum i2c_slave_event, u8 *); | |
1da177e4 | 53 | |
de477254 | 54 | struct module; |
d3e1b617 | 55 | struct property_entry; |
de477254 | 56 | |
23af8400 | 57 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
1da177e4 LT |
58 | /* |
59 | * The master routines are the ones normally used to transmit data to devices | |
438d6c2c DB |
60 | * on a bus (or read from them). Apart from two basic transfer functions to |
61 | * transmit one message at a time, a more complex version can be used to | |
1da177e4 | 62 | * transmit an arbitrary number of messages without interruption. |
0c43ea54 | 63 | * @count must be be less than 64k since msg.len is u16. |
1da177e4 | 64 | */ |
0cc43a18 JD |
65 | extern int i2c_master_send(const struct i2c_client *client, const char *buf, |
66 | int count); | |
67 | extern int i2c_master_recv(const struct i2c_client *client, char *buf, | |
3ae70dee | 68 | int count); |
1da177e4 LT |
69 | |
70 | /* Transfer num messages. | |
71 | */ | |
3ae70dee JD |
72 | extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, |
73 | int num); | |
b37d2a3a JD |
74 | /* Unlocked flavor */ |
75 | extern int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, | |
76 | int num); | |
1da177e4 LT |
77 | |
78 | /* This is the very generalized SMBus access routine. You probably do not | |
79 | want to use this, though; one of the functions below may be much easier, | |
438d6c2c | 80 | and probably just as fast. |
1da177e4 LT |
81 | Note that we use i2c_adapter here, because you do not need a specific |
82 | smbus adapter to call this function. */ | |
3ae70dee JD |
83 | extern s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, |
84 | unsigned short flags, char read_write, u8 command, | |
85 | int size, union i2c_smbus_data *data); | |
1da177e4 LT |
86 | |
87 | /* Now follow the 'nice' access routines. These also document the calling | |
ae7193f7 | 88 | conventions of i2c_smbus_xfer. */ |
1da177e4 | 89 | |
0cc43a18 JD |
90 | extern s32 i2c_smbus_read_byte(const struct i2c_client *client); |
91 | extern s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value); | |
92 | extern s32 i2c_smbus_read_byte_data(const struct i2c_client *client, | |
93 | u8 command); | |
94 | extern s32 i2c_smbus_write_byte_data(const struct i2c_client *client, | |
3ae70dee | 95 | u8 command, u8 value); |
0cc43a18 JD |
96 | extern s32 i2c_smbus_read_word_data(const struct i2c_client *client, |
97 | u8 command); | |
98 | extern s32 i2c_smbus_write_word_data(const struct i2c_client *client, | |
3ae70dee | 99 | u8 command, u16 value); |
06a67848 JC |
100 | |
101 | static inline s32 | |
102 | i2c_smbus_read_word_swapped(const struct i2c_client *client, u8 command) | |
103 | { | |
104 | s32 value = i2c_smbus_read_word_data(client, command); | |
105 | ||
106 | return (value < 0) ? value : swab16(value); | |
107 | } | |
108 | ||
109 | static inline s32 | |
110 | i2c_smbus_write_word_swapped(const struct i2c_client *client, | |
111 | u8 command, u16 value) | |
112 | { | |
113 | return i2c_smbus_write_word_data(client, command, swab16(value)); | |
114 | } | |
115 | ||
b86a1bc8 | 116 | /* Returns the number of read bytes */ |
0cc43a18 | 117 | extern s32 i2c_smbus_read_block_data(const struct i2c_client *client, |
b86a1bc8 | 118 | u8 command, u8 *values); |
0cc43a18 | 119 | extern s32 i2c_smbus_write_block_data(const struct i2c_client *client, |
3ae70dee | 120 | u8 command, u8 length, const u8 *values); |
31ec5bc5 | 121 | /* Returns the number of read bytes */ |
0cc43a18 | 122 | extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, |
4b2643d7 | 123 | u8 command, u8 length, u8 *values); |
0cc43a18 | 124 | extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, |
21bbd691 | 125 | u8 command, u8 length, |
46f5ed75 | 126 | const u8 *values); |
01eef96e IT |
127 | extern s32 |
128 | i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, | |
129 | u8 command, u8 length, u8 *values); | |
23af8400 | 130 | #endif /* I2C */ |
1da177e4 | 131 | |
b4f21054 BT |
132 | enum i2c_alert_protocol { |
133 | I2C_PROTOCOL_SMBUS_ALERT, | |
e456cd37 | 134 | I2C_PROTOCOL_SMBUS_HOST_NOTIFY, |
b4f21054 BT |
135 | }; |
136 | ||
4735c98f JD |
137 | /** |
138 | * struct i2c_driver - represent an I2C device driver | |
139 | * @class: What kind of i2c device we instantiate (for detect) | |
fe6fc258 | 140 | * @attach_adapter: Callback for bus addition (deprecated) |
b8a1a4cd LJ |
141 | * @probe: Callback for device binding - soon to be deprecated |
142 | * @probe_new: New callback for device binding | |
729d6dd5 | 143 | * @remove: Callback for device unbinding |
96e21e4f | 144 | * @shutdown: Callback for device shutdown |
72d2e9f9 | 145 | * @alert: Alert callback, for example for the SMBus alert protocol |
96e21e4f JD |
146 | * @command: Callback for bus-wide signaling (optional) |
147 | * @driver: Device driver model driver | |
148 | * @id_table: List of I2C devices supported by this driver | |
4735c98f | 149 | * @detect: Callback for device detection |
c3813d6a | 150 | * @address_list: The I2C addresses to probe (for detect) |
4735c98f | 151 | * @clients: List of detected clients we created (for i2c-core use only) |
35d8b2e6 LR |
152 | * |
153 | * The driver.owner field should be set to the module owner of this driver. | |
154 | * The driver.name field should be set to the name of this driver. | |
4735c98f | 155 | * |
0ec13867 | 156 | * For automatic device detection, both @detect and @address_list must |
4735c98f JD |
157 | * be defined. @class should also be set, otherwise only devices forced |
158 | * with module parameters will be created. The detect function must | |
159 | * fill at least the name field of the i2c_board_info structure it is | |
160 | * handed upon successful detection, and possibly also the flags field. | |
161 | * | |
162 | * If @detect is missing, the driver will still work fine for enumerated | |
163 | * devices. Detected devices simply won't be supported. This is expected | |
164 | * for the many I2C/SMBus devices which can't be detected reliably, and | |
165 | * the ones which can always be enumerated in practice. | |
166 | * | |
167 | * The i2c_client structure which is handed to the @detect callback is | |
168 | * not a real i2c_client. It is initialized just enough so that you can | |
169 | * call i2c_smbus_read_byte_data and friends on it. Don't do anything | |
170 | * else with it. In particular, calling dev_dbg and friends on it is | |
171 | * not allowed. | |
1da177e4 | 172 | */ |
1da177e4 | 173 | struct i2c_driver { |
1da177e4 | 174 | unsigned int class; |
1da177e4 | 175 | |
19baba4c LPC |
176 | /* Notifies the driver that a new bus has appeared. You should avoid |
177 | * using this, it will be removed in a near future. | |
1da177e4 | 178 | */ |
fe6fc258 | 179 | int (*attach_adapter)(struct i2c_adapter *) __deprecated; |
1da177e4 | 180 | |
729d6dd5 | 181 | /* Standard driver model interfaces */ |
d2653e92 | 182 | int (*probe)(struct i2c_client *, const struct i2c_device_id *); |
a1d9e6e4 | 183 | int (*remove)(struct i2c_client *); |
7b4fbc50 | 184 | |
b8a1a4cd LJ |
185 | /* New driver model interface to aid the seamless removal of the |
186 | * current probe()'s, more commonly unused than used second parameter. | |
187 | */ | |
188 | int (*probe_new)(struct i2c_client *); | |
189 | ||
f37dd80a DB |
190 | /* driver model interfaces that don't relate to enumeration */ |
191 | void (*shutdown)(struct i2c_client *); | |
f37dd80a | 192 | |
b5527a77 JD |
193 | /* Alert callback, for example for the SMBus alert protocol. |
194 | * The format and meaning of the data value depends on the protocol. | |
195 | * For the SMBus alert protocol, there is a single bit of data passed | |
196 | * as the alert response's low bit ("event flag"). | |
e456cd37 BT |
197 | * For the SMBus Host Notify protocol, the data corresponds to the |
198 | * 16-bit payload data reported by the slave device acting as master. | |
b5527a77 | 199 | */ |
b4f21054 BT |
200 | void (*alert)(struct i2c_client *, enum i2c_alert_protocol protocol, |
201 | unsigned int data); | |
b5527a77 | 202 | |
1da177e4 LT |
203 | /* a ioctl like command that can be used to perform specific functions |
204 | * with the device. | |
205 | */ | |
3ae70dee | 206 | int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); |
1da177e4 LT |
207 | |
208 | struct device_driver driver; | |
d2653e92 | 209 | const struct i2c_device_id *id_table; |
4735c98f JD |
210 | |
211 | /* Device detection callback for automatic device creation */ | |
310ec792 | 212 | int (*detect)(struct i2c_client *, struct i2c_board_info *); |
c3813d6a | 213 | const unsigned short *address_list; |
4735c98f | 214 | struct list_head clients; |
1da177e4 LT |
215 | }; |
216 | #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) | |
217 | ||
2096b956 DB |
218 | /** |
219 | * struct i2c_client - represent an I2C slave device | |
d64f73be DB |
220 | * @flags: I2C_CLIENT_TEN indicates the device uses a ten bit chip address; |
221 | * I2C_CLIENT_PEC indicates it uses SMBus Packet Error Checking | |
2096b956 DB |
222 | * @addr: Address used on the I2C bus connected to the parent adapter. |
223 | * @name: Indicates the type of the device, usually a chip name that's | |
224 | * generic enough to hide second-sourcing and compatible revisions. | |
d64f73be | 225 | * @adapter: manages the bus segment hosting this I2C device |
2096b956 | 226 | * @dev: Driver model device node for the slave. |
d64f73be | 227 | * @irq: indicates the IRQ generated by this device (if any) |
99cd8e25 JD |
228 | * @detected: member of an i2c_driver.clients list or i2c-core's |
229 | * userspace_devices list | |
4b1acc43 WS |
230 | * @slave_cb: Callback when I2C slave mode of an adapter is used. The adapter |
231 | * calls it to pass on slave events to the slave driver. | |
2096b956 DB |
232 | * |
233 | * An i2c_client identifies a single device (i.e. chip) connected to an | |
d64f73be DB |
234 | * i2c bus. The behaviour exposed to Linux is defined by the driver |
235 | * managing the device. | |
1da177e4 LT |
236 | */ |
237 | struct i2c_client { | |
2096b956 | 238 | unsigned short flags; /* div., see below */ |
438d6c2c | 239 | unsigned short addr; /* chip address - NOTE: 7bit */ |
1da177e4 | 240 | /* addresses are stored in the */ |
5071860a | 241 | /* _LOWER_ 7 bits */ |
2096b956 | 242 | char name[I2C_NAME_SIZE]; |
1da177e4 | 243 | struct i2c_adapter *adapter; /* the adapter we sit on */ |
1da177e4 | 244 | struct device dev; /* the device structure */ |
8e29da9e | 245 | int irq; /* irq issued by device */ |
4735c98f | 246 | struct list_head detected; |
d5fd120e | 247 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 | 248 | i2c_slave_cb_t slave_cb; /* callback for slave mode */ |
d5fd120e | 249 | #endif |
1da177e4 LT |
250 | }; |
251 | #define to_i2c_client(d) container_of(d, struct i2c_client, dev) | |
252 | ||
9b766b81 | 253 | extern struct i2c_client *i2c_verify_client(struct device *dev); |
643dd09e | 254 | extern struct i2c_adapter *i2c_verify_adapter(struct device *dev); |
5f441fca LJ |
255 | extern const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
256 | const struct i2c_client *client); | |
9b766b81 | 257 | |
a61fc683 BG |
258 | static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj) |
259 | { | |
d75d53cd MH |
260 | struct device * const dev = container_of(kobj, struct device, kobj); |
261 | return to_i2c_client(dev); | |
a61fc683 BG |
262 | } |
263 | ||
7d1d8999 | 264 | static inline void *i2c_get_clientdata(const struct i2c_client *dev) |
1da177e4 | 265 | { |
3ae70dee | 266 | return dev_get_drvdata(&dev->dev); |
1da177e4 LT |
267 | } |
268 | ||
3ae70dee | 269 | static inline void i2c_set_clientdata(struct i2c_client *dev, void *data) |
1da177e4 | 270 | { |
3ae70dee | 271 | dev_set_drvdata(&dev->dev, data); |
1da177e4 LT |
272 | } |
273 | ||
4b1acc43 WS |
274 | /* I2C slave support */ |
275 | ||
d5fd120e | 276 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 | 277 | enum i2c_slave_event { |
5b77d162 WS |
278 | I2C_SLAVE_READ_REQUESTED, |
279 | I2C_SLAVE_WRITE_REQUESTED, | |
280 | I2C_SLAVE_READ_PROCESSED, | |
281 | I2C_SLAVE_WRITE_RECEIVED, | |
4b1acc43 WS |
282 | I2C_SLAVE_STOP, |
283 | }; | |
284 | ||
285 | extern int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb); | |
286 | extern int i2c_slave_unregister(struct i2c_client *client); | |
cefae802 | 287 | extern bool i2c_detect_slave_mode(struct device *dev); |
4b1acc43 WS |
288 | |
289 | static inline int i2c_slave_event(struct i2c_client *client, | |
290 | enum i2c_slave_event event, u8 *val) | |
291 | { | |
292 | return client->slave_cb(client, event, val); | |
293 | } | |
d5fd120e | 294 | #endif |
4b1acc43 | 295 | |
9c1600ed DB |
296 | /** |
297 | * struct i2c_board_info - template for device creation | |
eb8a7908 | 298 | * @type: chip type, to initialize i2c_client.name |
9c1600ed DB |
299 | * @flags: to initialize i2c_client.flags |
300 | * @addr: stored in i2c_client.addr | |
301 | * @platform_data: stored in i2c_client.dev.platform_data | |
11f1f2af | 302 | * @archdata: copied into i2c_client.dev.archdata |
72d2e9f9 | 303 | * @of_node: pointer to OpenFirmware device node |
ce793486 | 304 | * @fwnode: device node supplied by the platform firmware |
d3e1b617 | 305 | * @properties: additional device properties for the device |
9c1600ed | 306 | * @irq: stored in i2c_client.irq |
d64f73be | 307 | * |
9c1600ed DB |
308 | * I2C doesn't actually support hardware probing, although controllers and |
309 | * devices may be able to use I2C_SMBUS_QUICK to tell whether or not there's | |
310 | * a device at a given address. Drivers commonly need more information than | |
311 | * that, such as chip type, configuration, associated IRQ, and so on. | |
312 | * | |
313 | * i2c_board_info is used to build tables of information listing I2C devices | |
729d6dd5 JD |
314 | * that are present. This information is used to grow the driver model tree. |
315 | * For mainboards this is done statically using i2c_register_board_info(); | |
316 | * bus numbers identify adapters that aren't yet available. For add-on boards, | |
317 | * i2c_new_device() does this dynamically with the adapter already known. | |
9c1600ed DB |
318 | */ |
319 | struct i2c_board_info { | |
9c1600ed DB |
320 | char type[I2C_NAME_SIZE]; |
321 | unsigned short flags; | |
322 | unsigned short addr; | |
323 | void *platform_data; | |
11f1f2af | 324 | struct dev_archdata *archdata; |
d12d42f7 | 325 | struct device_node *of_node; |
ce793486 | 326 | struct fwnode_handle *fwnode; |
d3e1b617 | 327 | const struct property_entry *properties; |
9c1600ed DB |
328 | int irq; |
329 | }; | |
330 | ||
331 | /** | |
3760f736 JD |
332 | * I2C_BOARD_INFO - macro used to list an i2c device and its address |
333 | * @dev_type: identifies the device type | |
9c1600ed DB |
334 | * @dev_addr: the device's address on the bus. |
335 | * | |
336 | * This macro initializes essential fields of a struct i2c_board_info, | |
337 | * declaring what has been provided on a particular board. Optional | |
3760f736 JD |
338 | * fields (such as associated irq, or device-specific platform_data) |
339 | * are provided using conventional syntax. | |
9c1600ed | 340 | */ |
3ae70dee | 341 | #define I2C_BOARD_INFO(dev_type, dev_addr) \ |
c758e8cf | 342 | .type = dev_type, .addr = (dev_addr) |
9c1600ed DB |
343 | |
344 | ||
23af8400 | 345 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
9c1600ed DB |
346 | /* Add-on boards should register/unregister their devices; e.g. a board |
347 | * with integrated I2C, a config eeprom, sensors, and a codec that's | |
348 | * used in conjunction with the primary hardware. | |
349 | */ | |
350 | extern struct i2c_client * | |
351 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info); | |
352 | ||
12b5053a JD |
353 | /* If you don't know the exact address of an I2C device, use this variant |
354 | * instead, which can probe for device presence in a list of possible | |
9a94241a JD |
355 | * addresses. The "probe" callback function is optional. If it is provided, |
356 | * it must return 1 on successful probe, 0 otherwise. If it is not provided, | |
357 | * a default probing method is used. | |
12b5053a JD |
358 | */ |
359 | extern struct i2c_client * | |
360 | i2c_new_probed_device(struct i2c_adapter *adap, | |
361 | struct i2c_board_info *info, | |
9a94241a JD |
362 | unsigned short const *addr_list, |
363 | int (*probe)(struct i2c_adapter *, unsigned short addr)); | |
12b5053a | 364 | |
d44f19d5 JD |
365 | /* Common custom probe functions */ |
366 | extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); | |
367 | ||
e9f1373b DB |
368 | /* For devices that use several addresses, use i2c_new_dummy() to make |
369 | * client handles for the extra addresses. | |
370 | */ | |
371 | extern struct i2c_client * | |
60b129d7 | 372 | i2c_new_dummy(struct i2c_adapter *adap, u16 address); |
e9f1373b | 373 | |
0f614d83 JMH |
374 | extern struct i2c_client * |
375 | i2c_new_secondary_device(struct i2c_client *client, | |
376 | const char *name, | |
377 | u16 default_addr); | |
378 | ||
9c1600ed | 379 | extern void i2c_unregister_device(struct i2c_client *); |
23af8400 | 380 | #endif /* I2C */ |
9c1600ed DB |
381 | |
382 | /* Mainboard arch_initcall() code should register all its I2C devices. | |
383 | * This is done at arch_initcall time, before declaring any i2c adapters. | |
384 | * Modules for add-on boards must use other calls. | |
385 | */ | |
26386763 | 386 | #ifdef CONFIG_I2C_BOARDINFO |
9c1600ed | 387 | extern int |
3ae70dee JD |
388 | i2c_register_board_info(int busnum, struct i2c_board_info const *info, |
389 | unsigned n); | |
26386763 DB |
390 | #else |
391 | static inline int | |
3ae70dee JD |
392 | i2c_register_board_info(int busnum, struct i2c_board_info const *info, |
393 | unsigned n) | |
26386763 DB |
394 | { |
395 | return 0; | |
396 | } | |
23af8400 | 397 | #endif /* I2C_BOARDINFO */ |
9c1600ed | 398 | |
25ee33fb BD |
399 | /** |
400 | * struct i2c_algorithm - represent I2C transfer method | |
401 | * @master_xfer: Issue a set of i2c transactions to the given I2C adapter | |
402 | * defined by the msgs array, with num messages available to transfer via | |
403 | * the adapter specified by adap. | |
404 | * @smbus_xfer: Issue smbus transactions to the given I2C adapter. If this | |
405 | * is not present, then the bus layer will try and convert the SMBus calls | |
406 | * into I2C transfers instead. | |
407 | * @functionality: Return the flags that this algorithm/adapter pair supports | |
408 | * from the I2C_FUNC_* flags. | |
4b1acc43 WS |
409 | * @reg_slave: Register given client to I2C slave mode of this adapter |
410 | * @unreg_slave: Unregister given client from I2C slave mode of this adapter | |
25ee33fb | 411 | * |
1da177e4 LT |
412 | * The following structs are for those who like to implement new bus drivers: |
413 | * i2c_algorithm is the interface to a class of hardware solutions which can | |
414 | * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584 | |
415 | * to name two of the most common. | |
25ee33fb BD |
416 | * |
417 | * The return codes from the @master_xfer field should indicate the type of | |
f353d71f | 418 | * error code that occurred during the transfer, as documented in the kernel |
25ee33fb | 419 | * Documentation file Documentation/i2c/fault-codes. |
1da177e4 LT |
420 | */ |
421 | struct i2c_algorithm { | |
1da177e4 | 422 | /* If an adapter algorithm can't do I2C-level access, set master_xfer |
438d6c2c | 423 | to NULL. If an adapter algorithm can do SMBus access, set |
1da177e4 LT |
424 | smbus_xfer. If set to NULL, the SMBus protocol is simulated |
425 | using common I2C messages */ | |
8ced8eee JD |
426 | /* master_xfer should return the number of messages successfully |
427 | processed, or a negative value on error */ | |
3ae70dee JD |
428 | int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, |
429 | int num); | |
438d6c2c | 430 | int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr, |
3ae70dee JD |
431 | unsigned short flags, char read_write, |
432 | u8 command, int size, union i2c_smbus_data *data); | |
1da177e4 | 433 | |
1da177e4 LT |
434 | /* To determine what the adapter supports */ |
435 | u32 (*functionality) (struct i2c_adapter *); | |
4b1acc43 | 436 | |
d5fd120e | 437 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 WS |
438 | int (*reg_slave)(struct i2c_client *client); |
439 | int (*unreg_slave)(struct i2c_client *client); | |
d5fd120e | 440 | #endif |
1da177e4 LT |
441 | }; |
442 | ||
d1ed7985 PR |
443 | /** |
444 | * struct i2c_lock_operations - represent I2C locking operations | |
445 | * @lock_bus: Get exclusive access to an I2C bus segment | |
446 | * @trylock_bus: Try to get exclusive access to an I2C bus segment | |
447 | * @unlock_bus: Release exclusive access to an I2C bus segment | |
448 | * | |
449 | * The main operations are wrapped by i2c_lock_bus and i2c_unlock_bus. | |
450 | */ | |
451 | struct i2c_lock_operations { | |
452 | void (*lock_bus)(struct i2c_adapter *, unsigned int flags); | |
453 | int (*trylock_bus)(struct i2c_adapter *, unsigned int flags); | |
454 | void (*unlock_bus)(struct i2c_adapter *, unsigned int flags); | |
455 | }; | |
456 | ||
e1dba01c WS |
457 | /** |
458 | * struct i2c_timings - I2C timing information | |
459 | * @bus_freq_hz: the bus frequency in Hz | |
460 | * @scl_rise_ns: time SCL signal takes to rise in ns; t(r) in the I2C specification | |
461 | * @scl_fall_ns: time SCL signal takes to fall in ns; t(f) in the I2C specification | |
462 | * @scl_int_delay_ns: time IP core additionally needs to setup SCL in ns | |
463 | * @sda_fall_ns: time SDA signal takes to fall in ns; t(f) in the I2C specification | |
464 | */ | |
465 | struct i2c_timings { | |
466 | u32 bus_freq_hz; | |
467 | u32 scl_rise_ns; | |
468 | u32 scl_fall_ns; | |
469 | u32 scl_int_delay_ns; | |
470 | u32 sda_fall_ns; | |
471 | }; | |
472 | ||
5f9296ba VK |
473 | /** |
474 | * struct i2c_bus_recovery_info - I2C bus recovery information | |
475 | * @recover_bus: Recover routine. Either pass driver's recover_bus() routine, or | |
476 | * i2c_generic_scl_recovery() or i2c_generic_gpio_recovery(). | |
477 | * @get_scl: This gets current value of SCL line. Mandatory for generic SCL | |
478 | * recovery. Used internally for generic GPIO recovery. | |
479 | * @set_scl: This sets/clears SCL line. Mandatory for generic SCL recovery. Used | |
480 | * internally for generic GPIO recovery. | |
481 | * @get_sda: This gets current value of SDA line. Optional for generic SCL | |
482 | * recovery. Used internally, if sda_gpio is a valid GPIO, for generic GPIO | |
483 | * recovery. | |
484 | * @prepare_recovery: This will be called before starting recovery. Platform may | |
485 | * configure padmux here for SDA/SCL line or something else they want. | |
486 | * @unprepare_recovery: This will be called after completing recovery. Platform | |
487 | * may configure padmux here for SDA/SCL line or something else they want. | |
488 | * @scl_gpio: gpio number of the SCL line. Only required for GPIO recovery. | |
489 | * @sda_gpio: gpio number of the SDA line. Only required for GPIO recovery. | |
490 | */ | |
491 | struct i2c_bus_recovery_info { | |
492 | int (*recover_bus)(struct i2c_adapter *); | |
493 | ||
494 | int (*get_scl)(struct i2c_adapter *); | |
495 | void (*set_scl)(struct i2c_adapter *, int val); | |
496 | int (*get_sda)(struct i2c_adapter *); | |
497 | ||
2b2190a3 GS |
498 | void (*prepare_recovery)(struct i2c_adapter *); |
499 | void (*unprepare_recovery)(struct i2c_adapter *); | |
5f9296ba VK |
500 | |
501 | /* gpio recovery */ | |
502 | int scl_gpio; | |
503 | int sda_gpio; | |
504 | }; | |
505 | ||
506 | int i2c_recover_bus(struct i2c_adapter *adap); | |
507 | ||
508 | /* Generic recovery routines */ | |
509 | int i2c_generic_gpio_recovery(struct i2c_adapter *adap); | |
510 | int i2c_generic_scl_recovery(struct i2c_adapter *adap); | |
511 | ||
2187f03a WS |
512 | /** |
513 | * struct i2c_adapter_quirks - describe flaws of an i2c adapter | |
514 | * @flags: see I2C_AQ_* for possible flags and read below | |
515 | * @max_num_msgs: maximum number of messages per transfer | |
516 | * @max_write_len: maximum length of a write message | |
517 | * @max_read_len: maximum length of a read message | |
518 | * @max_comb_1st_msg_len: maximum length of the first msg in a combined message | |
519 | * @max_comb_2nd_msg_len: maximum length of the second msg in a combined message | |
520 | * | |
521 | * Note about combined messages: Some I2C controllers can only send one message | |
522 | * per transfer, plus something called combined message or write-then-read. | |
523 | * This is (usually) a small write message followed by a read message and | |
524 | * barely enough to access register based devices like EEPROMs. There is a flag | |
525 | * to support this mode. It implies max_num_msg = 2 and does the length checks | |
526 | * with max_comb_*_len because combined message mode usually has its own | |
527 | * limitations. Because of HW implementations, some controllers can actually do | |
528 | * write-then-anything or other variants. To support that, write-then-read has | |
529 | * been broken out into smaller bits like write-first and read-second which can | |
530 | * be combined as needed. | |
531 | */ | |
532 | ||
533 | struct i2c_adapter_quirks { | |
534 | u64 flags; | |
535 | int max_num_msgs; | |
536 | u16 max_write_len; | |
537 | u16 max_read_len; | |
538 | u16 max_comb_1st_msg_len; | |
539 | u16 max_comb_2nd_msg_len; | |
540 | }; | |
541 | ||
542 | /* enforce max_num_msgs = 2 and use max_comb_*_len for length checks */ | |
543 | #define I2C_AQ_COMB BIT(0) | |
544 | /* first combined message must be write */ | |
545 | #define I2C_AQ_COMB_WRITE_FIRST BIT(1) | |
546 | /* second combined message must be read */ | |
547 | #define I2C_AQ_COMB_READ_SECOND BIT(2) | |
548 | /* both combined messages must have the same target address */ | |
549 | #define I2C_AQ_COMB_SAME_ADDR BIT(3) | |
550 | /* convenience macro for typical write-then read case */ | |
551 | #define I2C_AQ_COMB_WRITE_THEN_READ (I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | \ | |
552 | I2C_AQ_COMB_READ_SECOND | I2C_AQ_COMB_SAME_ADDR) | |
749de3da NC |
553 | /* clock stretching is not supported */ |
554 | #define I2C_AQ_NO_CLK_STRETCH BIT(4) | |
2187f03a | 555 | |
1da177e4 LT |
556 | /* |
557 | * i2c_adapter is the structure used to identify a physical i2c bus along | |
558 | * with the access algorithms necessary to access it. | |
559 | */ | |
560 | struct i2c_adapter { | |
561 | struct module *owner; | |
14f55f7a | 562 | unsigned int class; /* classes to allow probing for */ |
af71ff69 | 563 | const struct i2c_algorithm *algo; /* the algorithm to access the bus */ |
1da177e4 LT |
564 | void *algo_data; |
565 | ||
1da177e4 | 566 | /* data fields that are valid for all devices */ |
d1ed7985 | 567 | const struct i2c_lock_operations *lock_ops; |
194684e5 | 568 | struct rt_mutex bus_lock; |
6ef91fcc | 569 | struct rt_mutex mux_lock; |
1da177e4 | 570 | |
cd97f39b | 571 | int timeout; /* in jiffies */ |
1da177e4 LT |
572 | int retries; |
573 | struct device dev; /* the adapter device */ | |
1da177e4 | 574 | |
1da177e4 | 575 | int nr; |
2096b956 | 576 | char name[48]; |
1da177e4 | 577 | struct completion dev_released; |
6629dcff | 578 | |
dafc50d1 | 579 | struct mutex userspace_clients_lock; |
6629dcff | 580 | struct list_head userspace_clients; |
5f9296ba VK |
581 | |
582 | struct i2c_bus_recovery_info *bus_recovery_info; | |
2187f03a | 583 | const struct i2c_adapter_quirks *quirks; |
4d5538f5 BT |
584 | |
585 | struct irq_domain *host_notify_domain; | |
1da177e4 | 586 | }; |
ef2c8321 | 587 | #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) |
1da177e4 | 588 | |
7d1d8999 | 589 | static inline void *i2c_get_adapdata(const struct i2c_adapter *dev) |
1da177e4 | 590 | { |
3ae70dee | 591 | return dev_get_drvdata(&dev->dev); |
1da177e4 LT |
592 | } |
593 | ||
3ae70dee | 594 | static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data) |
1da177e4 | 595 | { |
3ae70dee | 596 | dev_set_drvdata(&dev->dev, data); |
1da177e4 LT |
597 | } |
598 | ||
97cc4d49 JD |
599 | static inline struct i2c_adapter * |
600 | i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter) | |
0826374b | 601 | { |
2fac2b89 | 602 | #if IS_ENABLED(CONFIG_I2C_MUX) |
97cc4d49 JD |
603 | struct device *parent = adapter->dev.parent; |
604 | ||
605 | if (parent != NULL && parent->type == &i2c_adapter_type) | |
606 | return to_i2c_adapter(parent); | |
607 | else | |
3923172b | 608 | #endif |
97cc4d49 | 609 | return NULL; |
0826374b ML |
610 | } |
611 | ||
7ae31482 JD |
612 | int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)); |
613 | ||
fe61e07e | 614 | /* Adapter locking functions, exported for shared pin cases */ |
8320f495 PR |
615 | #define I2C_LOCK_ROOT_ADAPTER BIT(0) |
616 | #define I2C_LOCK_SEGMENT BIT(1) | |
617 | ||
618 | /** | |
619 | * i2c_lock_bus - Get exclusive access to an I2C bus segment | |
620 | * @adapter: Target I2C bus segment | |
621 | * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT | |
622 | * locks only this branch in the adapter tree | |
623 | */ | |
624 | static inline void | |
625 | i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags) | |
626 | { | |
d1ed7985 | 627 | adapter->lock_ops->lock_bus(adapter, flags); |
8320f495 PR |
628 | } |
629 | ||
fb79e09a PR |
630 | /** |
631 | * i2c_trylock_bus - Try to get exclusive access to an I2C bus segment | |
632 | * @adapter: Target I2C bus segment | |
633 | * @flags: I2C_LOCK_ROOT_ADAPTER tries to locks the root i2c adapter, | |
634 | * I2C_LOCK_SEGMENT tries to lock only this branch in the adapter tree | |
635 | * | |
636 | * Return: true if the I2C bus segment is locked, false otherwise | |
637 | */ | |
638 | static inline int | |
639 | i2c_trylock_bus(struct i2c_adapter *adapter, unsigned int flags) | |
640 | { | |
d1ed7985 | 641 | return adapter->lock_ops->trylock_bus(adapter, flags); |
fb79e09a PR |
642 | } |
643 | ||
8320f495 PR |
644 | /** |
645 | * i2c_unlock_bus - Release exclusive access to an I2C bus segment | |
646 | * @adapter: Target I2C bus segment | |
647 | * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT | |
648 | * unlocks only this branch in the adapter tree | |
649 | */ | |
650 | static inline void | |
651 | i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags) | |
652 | { | |
d1ed7985 | 653 | adapter->lock_ops->unlock_bus(adapter, flags); |
8320f495 PR |
654 | } |
655 | ||
656 | static inline void | |
657 | i2c_lock_adapter(struct i2c_adapter *adapter) | |
658 | { | |
659 | i2c_lock_bus(adapter, I2C_LOCK_ROOT_ADAPTER); | |
660 | } | |
661 | ||
662 | static inline void | |
663 | i2c_unlock_adapter(struct i2c_adapter *adapter) | |
664 | { | |
665 | i2c_unlock_bus(adapter, I2C_LOCK_ROOT_ADAPTER); | |
666 | } | |
afa08974 | 667 | |
1da177e4 | 668 | /*flags for the client struct: */ |
c5ebb387 WS |
669 | #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ |
670 | #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ | |
3bbb835d | 671 | /* Must equal I2C_M_TEN below */ |
c5ebb387 | 672 | #define I2C_CLIENT_SLAVE 0x20 /* we are the slave */ |
331c3425 | 673 | #define I2C_CLIENT_HOST_NOTIFY 0x40 /* We want to use I2C host notify */ |
c5ebb387 WS |
674 | #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */ |
675 | #define I2C_CLIENT_SCCB 0x9000 /* Use Omnivision SCCB protocol */ | |
d47726c5 | 676 | /* Must match I2C_M_STOP|IGNORE_NAK */ |
1da177e4 LT |
677 | |
678 | /* i2c adapter classes (bitmask) */ | |
679 | #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ | |
c1b6b4f2 | 680 | #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */ |
774466ad | 681 | #define I2C_CLASS_SPD (1<<7) /* Memory modules */ |
0c176170 | 682 | #define I2C_CLASS_DEPRECATED (1<<8) /* Warn users that adapter will stop using classes */ |
1da177e4 | 683 | |
1da177e4 LT |
684 | /* Internal numbers to terminate lists */ |
685 | #define I2C_CLIENT_END 0xfffeU | |
1da177e4 | 686 | |
c7036673 HV |
687 | /* Construct an I2C_CLIENT_END-terminated array of i2c addresses */ |
688 | #define I2C_ADDRS(addr, addrs...) \ | |
689 | ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END }) | |
690 | ||
1da177e4 LT |
691 | |
692 | /* ----- functions exported by i2c.o */ | |
693 | ||
694 | /* administration... | |
695 | */ | |
23af8400 | 696 | #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) |
1da177e4 | 697 | extern int i2c_add_adapter(struct i2c_adapter *); |
71546300 | 698 | extern void i2c_del_adapter(struct i2c_adapter *); |
6e13e641 | 699 | extern int i2c_add_numbered_adapter(struct i2c_adapter *); |
1da177e4 | 700 | |
de59cf9e | 701 | extern int i2c_register_driver(struct module *, struct i2c_driver *); |
b3e82096 | 702 | extern void i2c_del_driver(struct i2c_driver *); |
1da177e4 | 703 | |
eb5589a8 PG |
704 | /* use a define to avoid include chaining to get THIS_MODULE */ |
705 | #define i2c_add_driver(driver) \ | |
706 | i2c_register_driver(THIS_MODULE, driver) | |
de59cf9e | 707 | |
e48d3319 JD |
708 | extern struct i2c_client *i2c_use_client(struct i2c_client *client); |
709 | extern void i2c_release_client(struct i2c_client *client); | |
1da177e4 LT |
710 | |
711 | /* call the i2c_client->command() of all attached clients with | |
712 | * the given arguments */ | |
713 | extern void i2c_clients_command(struct i2c_adapter *adap, | |
714 | unsigned int cmd, void *arg); | |
715 | ||
d735b34d | 716 | extern struct i2c_adapter *i2c_get_adapter(int nr); |
1da177e4 | 717 | extern void i2c_put_adapter(struct i2c_adapter *adap); |
8dd1fe15 | 718 | extern unsigned int i2c_adapter_depth(struct i2c_adapter *adapter); |
1da177e4 | 719 | |
e1dba01c | 720 | void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults); |
1da177e4 LT |
721 | |
722 | /* Return the functionality mask */ | |
723 | static inline u32 i2c_get_functionality(struct i2c_adapter *adap) | |
724 | { | |
725 | return adap->algo->functionality(adap); | |
726 | } | |
727 | ||
728 | /* Return 1 if adapter supports everything we need, 0 if not. */ | |
729 | static inline int i2c_check_functionality(struct i2c_adapter *adap, u32 func) | |
730 | { | |
731 | return (func & i2c_get_functionality(adap)) == func; | |
732 | } | |
733 | ||
cfa576db NC |
734 | /** |
735 | * i2c_check_quirks() - Function for checking the quirk flags in an i2c adapter | |
736 | * @adap: i2c adapter | |
737 | * @quirks: quirk flags | |
738 | * | |
739 | * Return: true if the adapter has all the specified quirk flags, false if not | |
740 | */ | |
741 | static inline bool i2c_check_quirks(struct i2c_adapter *adap, u64 quirks) | |
742 | { | |
743 | if (!adap->quirks) | |
744 | return false; | |
745 | return (adap->quirks->flags & quirks) == quirks; | |
746 | } | |
747 | ||
3ae70dee | 748 | /* Return the adapter number for a specific adapter */ |
cdcb1921 JD |
749 | static inline int i2c_adapter_id(struct i2c_adapter *adap) |
750 | { | |
751 | return adap->nr; | |
752 | } | |
7c92784a | 753 | |
a16d6ebc WS |
754 | static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg) |
755 | { | |
756 | return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0); | |
757 | } | |
758 | ||
4d5538f5 | 759 | int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr); |
7c92784a | 760 | /** |
c698d639 | 761 | * module_i2c_driver() - Helper macro for registering a modular I2C driver |
7c92784a LPC |
762 | * @__i2c_driver: i2c_driver struct |
763 | * | |
764 | * Helper macro for I2C drivers which do not do anything special in module | |
765 | * init/exit. This eliminates a lot of boilerplate. Each module may only | |
766 | * use this macro once, and calling it replaces module_init() and module_exit() | |
767 | */ | |
768 | #define module_i2c_driver(__i2c_driver) \ | |
769 | module_driver(__i2c_driver, i2c_add_driver, \ | |
770 | i2c_del_driver) | |
771 | ||
c698d639 PG |
772 | /** |
773 | * builtin_i2c_driver() - Helper macro for registering a builtin I2C driver | |
774 | * @__i2c_driver: i2c_driver struct | |
775 | * | |
776 | * Helper macro for I2C drivers which do not do anything special in their | |
777 | * init. This eliminates a lot of boilerplate. Each driver may only | |
778 | * use this macro once, and calling it replaces device_initcall(). | |
779 | */ | |
780 | #define builtin_i2c_driver(__i2c_driver) \ | |
781 | builtin_driver(__i2c_driver, i2c_add_driver) | |
782 | ||
23af8400 | 783 | #endif /* I2C */ |
907ddf89 | 784 | |
687b81d0 WS |
785 | #if IS_ENABLED(CONFIG_OF) |
786 | /* must call put_device() when done with returned i2c_client device */ | |
787 | extern struct i2c_client *of_find_i2c_device_by_node(struct device_node *node); | |
788 | ||
789 | /* must call put_device() when done with returned i2c_adapter device */ | |
790 | extern struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node); | |
791 | ||
48e9743d VZ |
792 | /* must call i2c_put_adapter() when done with returned i2c_adapter device */ |
793 | struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node); | |
e1dba01c | 794 | |
298d4de1 LJ |
795 | extern const struct of_device_id |
796 | *i2c_of_match_device(const struct of_device_id *matches, | |
797 | struct i2c_client *client); | |
798 | ||
687b81d0 WS |
799 | #else |
800 | ||
801 | static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) | |
802 | { | |
803 | return NULL; | |
804 | } | |
805 | ||
806 | static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) | |
807 | { | |
808 | return NULL; | |
809 | } | |
48e9743d VZ |
810 | |
811 | static inline struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) | |
812 | { | |
813 | return NULL; | |
814 | } | |
298d4de1 LJ |
815 | |
816 | static inline const struct of_device_id | |
817 | *i2c_of_match_device(const struct of_device_id *matches, | |
818 | struct i2c_client *client) | |
819 | { | |
820 | return NULL; | |
821 | } | |
822 | ||
687b81d0 WS |
823 | #endif /* CONFIG_OF */ |
824 | ||
5853b22d JN |
825 | #if IS_ENABLED(CONFIG_ACPI) |
826 | u32 i2c_acpi_find_bus_speed(struct device *dev); | |
827 | #else | |
828 | static inline u32 i2c_acpi_find_bus_speed(struct device *dev) | |
829 | { | |
830 | return 0; | |
831 | } | |
832 | #endif /* CONFIG_ACPI */ | |
833 | ||
1da177e4 | 834 | #endif /* _LINUX_I2C_H */ |