1 /* ------------------------------------------------------------------------- */ 2 /* */ 3 /* i2c.h - definitions for the i2c-bus interface */ 4 /* */ 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 20 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 21 MA 02110-1301 USA. */ 22 /* ------------------------------------------------------------------------- */ 23 24 /* With some changes from Kyösti Mälkki <[email protected]> and 25 Frodo Looijaard <[email protected]> */ 26 #ifndef _LINUX_I2C_H 27 #define _LINUX_I2C_H 28 29 #include <linux/mod_devicetable.h> 30 #include <linux/device.h> /* for struct device */ 31 #include <linux/sched.h> /* for completion */ 32 #include <linux/mutex.h> 33 #include <linux/irqdomain.h> /* for Host Notify IRQ */ 34 #include <linux/of.h> /* for struct device_node */ 35 #include <linux/swab.h> /* for swab16 */ 36 #include <uapi/linux/i2c.h> 37 38 extern struct bus_type i2c_bus_type; 39 extern struct device_type i2c_adapter_type; 40 41 /* --- General options ------------------------------------------------ */ 42 43 struct i2c_msg; 44 struct i2c_algorithm; 45 struct i2c_adapter; 46 struct i2c_client; 47 struct i2c_driver; 48 union i2c_smbus_data; 49 struct i2c_board_info; 50 enum i2c_slave_event; 51 typedef int (*i2c_slave_cb_t)(struct i2c_client *, enum i2c_slave_event, u8 *); 52 53 struct module; 54 struct property_entry; 55 56 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 57 /* 58 * The master routines are the ones normally used to transmit data to devices 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 61 * transmit an arbitrary number of messages without interruption. 62 * @count must be be less than 64k since msg.len is u16. 63 */ 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, 67 int count); 68 69 /* Transfer num messages. 70 */ 71 extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, 72 int num); 73 /* Unlocked flavor */ 74 extern int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, 75 int num); 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, 79 and probably just as fast. 80 Note that we use i2c_adapter here, because you do not need a specific 81 smbus adapter to call this function. */ 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); 85 86 /* Now follow the 'nice' access routines. These also document the calling 87 conventions of i2c_smbus_xfer. */ 88 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, 94 u8 command, u8 value); 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, 98 u8 command, u16 value); 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 } 114 115 /* Returns the number of read bytes */ 116 extern s32 i2c_smbus_read_block_data(const struct i2c_client *client, 117 u8 command, u8 *values); 118 extern s32 i2c_smbus_write_block_data(const struct i2c_client *client, 119 u8 command, u8 length, const u8 *values); 120 /* Returns the number of read bytes */ 121 extern s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, 122 u8 command, u8 length, u8 *values); 123 extern s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, 124 u8 command, u8 length, 125 const u8 *values); 126 extern s32 127 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, 128 u8 command, u8 length, u8 *values); 129 #endif /* I2C */ 130 131 enum i2c_alert_protocol { 132 I2C_PROTOCOL_SMBUS_ALERT, 133 I2C_PROTOCOL_SMBUS_HOST_NOTIFY, 134 }; 135 136 /** 137 * struct i2c_driver - represent an I2C device driver 138 * @class: What kind of i2c device we instantiate (for detect) 139 * @attach_adapter: Callback for bus addition (deprecated) 140 * @probe: Callback for device binding - soon to be deprecated 141 * @probe_new: New callback for device binding 142 * @remove: Callback for device unbinding 143 * @shutdown: Callback for device shutdown 144 * @alert: Alert callback, for example for the SMBus alert protocol 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 148 * @detect: Callback for device detection 149 * @address_list: The I2C addresses to probe (for detect) 150 * @clients: List of detected clients we created (for i2c-core use only) 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. 154 * 155 * For automatic device detection, both @detect and @address_list must 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. 171 */ 172 struct i2c_driver { 173 unsigned int class; 174 175 /* Notifies the driver that a new bus has appeared. You should avoid 176 * using this, it will be removed in a near future. 177 */ 178 int (*attach_adapter)(struct i2c_adapter *) __deprecated; 179 180 /* Standard driver model interfaces */ 181 int (*probe)(struct i2c_client *, const struct i2c_device_id *); 182 int (*remove)(struct i2c_client *); 183 184 /* 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 *); 188 189 /* driver model interfaces that don't relate to enumeration */ 190 void (*shutdown)(struct i2c_client *); 191 192 /* 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"). 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. 198 */ 199 void (*alert)(struct i2c_client *, enum i2c_alert_protocol protocol, 200 unsigned int data); 201 202 /* a ioctl like command that can be used to perform specific functions 203 * with the device. 204 */ 205 int (*command)(struct i2c_client *client, unsigned int cmd, void *arg); 206 207 struct device_driver driver; 208 const struct i2c_device_id *id_table; 209 210 /* Device detection callback for automatic device creation */ 211 int (*detect)(struct i2c_client *, struct i2c_board_info *); 212 const unsigned short *address_list; 213 struct list_head clients; 214 }; 215 #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) 216 217 /** 218 * struct i2c_client - represent an I2C slave device 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 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. 224 * @adapter: manages the bus segment hosting this I2C device 225 * @dev: Driver model device node for the slave. 226 * @irq: indicates the IRQ generated by this device (if any) 227 * @detected: member of an i2c_driver.clients list or i2c-core's 228 * userspace_devices list 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. 231 * 232 * An i2c_client identifies a single device (i.e. chip) connected to an 233 * i2c bus. The behaviour exposed to Linux is defined by the driver 234 * managing the device. 235 */ 236 struct i2c_client { 237 unsigned short flags; /* div., see below */ 238 unsigned short addr; /* chip address - NOTE: 7bit */ 239 /* addresses are stored in the */ 240 /* _LOWER_ 7 bits */ 241 char name[I2C_NAME_SIZE]; 242 struct i2c_adapter *adapter; /* the adapter we sit on */ 243 struct device dev; /* the device structure */ 244 int irq; /* irq issued by device */ 245 struct list_head detected; 246 #if IS_ENABLED(CONFIG_I2C_SLAVE) 247 i2c_slave_cb_t slave_cb; /* callback for slave mode */ 248 #endif 249 }; 250 #define to_i2c_client(d) container_of(d, struct i2c_client, dev) 251 252 extern struct i2c_client *i2c_verify_client(struct device *dev); 253 extern struct i2c_adapter *i2c_verify_adapter(struct device *dev); 254 extern const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, 255 const struct i2c_client *client); 256 257 static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj) 258 { 259 struct device * const dev = container_of(kobj, struct device, kobj); 260 return to_i2c_client(dev); 261 } 262 263 static inline void *i2c_get_clientdata(const struct i2c_client *dev) 264 { 265 return dev_get_drvdata(&dev->dev); 266 } 267 268 static inline void i2c_set_clientdata(struct i2c_client *dev, void *data) 269 { 270 dev_set_drvdata(&dev->dev, data); 271 } 272 273 /* I2C slave support */ 274 275 #if IS_ENABLED(CONFIG_I2C_SLAVE) 276 enum i2c_slave_event { 277 I2C_SLAVE_READ_REQUESTED, 278 I2C_SLAVE_WRITE_REQUESTED, 279 I2C_SLAVE_READ_PROCESSED, 280 I2C_SLAVE_WRITE_RECEIVED, 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 } 292 #endif 293 294 /** 295 * struct i2c_board_info - template for device creation 296 * @type: chip type, to initialize i2c_client.name 297 * @flags: to initialize i2c_client.flags 298 * @addr: stored in i2c_client.addr 299 * @platform_data: stored in i2c_client.dev.platform_data 300 * @archdata: copied into i2c_client.dev.archdata 301 * @of_node: pointer to OpenFirmware device node 302 * @fwnode: device node supplied by the platform firmware 303 * @properties: additional device properties for the device 304 * @irq: stored in i2c_client.irq 305 * 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 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. 316 */ 317 struct i2c_board_info { 318 char type[I2C_NAME_SIZE]; 319 unsigned short flags; 320 unsigned short addr; 321 void *platform_data; 322 struct dev_archdata *archdata; 323 struct device_node *of_node; 324 struct fwnode_handle *fwnode; 325 const struct property_entry *properties; 326 int irq; 327 }; 328 329 /** 330 * I2C_BOARD_INFO - macro used to list an i2c device and its address 331 * @dev_type: identifies the device type 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 336 * fields (such as associated irq, or device-specific platform_data) 337 * are provided using conventional syntax. 338 */ 339 #define I2C_BOARD_INFO(dev_type, dev_addr) \ 340 .type = dev_type, .addr = (dev_addr) 341 342 343 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 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); 350 351 /* 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 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. 356 */ 357 extern struct i2c_client * 358 i2c_new_probed_device(struct i2c_adapter *adap, 359 struct i2c_board_info *info, 360 unsigned short const *addr_list, 361 int (*probe)(struct i2c_adapter *, unsigned short addr)); 362 363 /* Common custom probe functions */ 364 extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); 365 366 /* 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 * 370 i2c_new_dummy(struct i2c_adapter *adap, u16 address); 371 372 extern struct i2c_client * 373 i2c_new_secondary_device(struct i2c_client *client, 374 const char *name, 375 u16 default_addr); 376 377 extern void i2c_unregister_device(struct i2c_client *); 378 #endif /* I2C */ 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 */ 384 #ifdef CONFIG_I2C_BOARDINFO 385 extern int 386 i2c_register_board_info(int busnum, struct i2c_board_info const *info, 387 unsigned n); 388 #else 389 static inline int 390 i2c_register_board_info(int busnum, struct i2c_board_info const *info, 391 unsigned n) 392 { 393 return 0; 394 } 395 #endif /* I2C_BOARDINFO */ 396 397 /** 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. 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 409 * 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. 414 * 415 * The return codes from the @master_xfer field should indicate the type of 416 * error code that occurred during the transfer, as documented in the kernel 417 * Documentation file Documentation/i2c/fault-codes. 418 */ 419 struct i2c_algorithm { 420 /* If an adapter algorithm can't do I2C-level access, set master_xfer 421 to NULL. If an adapter algorithm can do SMBus access, set 422 smbus_xfer. If set to NULL, the SMBus protocol is simulated 423 using common I2C messages */ 424 /* master_xfer should return the number of messages successfully 425 processed, or a negative value on error */ 426 int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, 427 int num); 428 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr, 429 unsigned short flags, char read_write, 430 u8 command, int size, union i2c_smbus_data *data); 431 432 /* To determine what the adapter supports */ 433 u32 (*functionality) (struct i2c_adapter *); 434 435 #if IS_ENABLED(CONFIG_I2C_SLAVE) 436 int (*reg_slave)(struct i2c_client *client); 437 int (*unreg_slave)(struct i2c_client *client); 438 #endif 439 }; 440 441 /** 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 }; 454 455 /** 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 }; 470 471 /** 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 *); 495 496 void (*prepare_recovery)(struct i2c_adapter *); 497 void (*unprepare_recovery)(struct i2c_adapter *); 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); 509 510 /** 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) 551 /* clock stretching is not supported */ 552 #define I2C_AQ_NO_CLK_STRETCH BIT(4) 553 554 /* 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; 560 unsigned int class; /* classes to allow probing for */ 561 const struct i2c_algorithm *algo; /* the algorithm to access the bus */ 562 void *algo_data; 563 564 /* data fields that are valid for all devices */ 565 const struct i2c_lock_operations *lock_ops; 566 struct rt_mutex bus_lock; 567 struct rt_mutex mux_lock; 568 569 int timeout; /* in jiffies */ 570 int retries; 571 struct device dev; /* the adapter device */ 572 573 int nr; 574 char name[48]; 575 struct completion dev_released; 576 577 struct mutex userspace_clients_lock; 578 struct list_head userspace_clients; 579 580 struct i2c_bus_recovery_info *bus_recovery_info; 581 const struct i2c_adapter_quirks *quirks; 582 583 struct irq_domain *host_notify_domain; 584 }; 585 #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) 586 587 static inline void *i2c_get_adapdata(const struct i2c_adapter *dev) 588 { 589 return dev_get_drvdata(&dev->dev); 590 } 591 592 static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data) 593 { 594 dev_set_drvdata(&dev->dev, data); 595 } 596 597 static inline struct i2c_adapter * 598 i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter) 599 { 600 #if IS_ENABLED(CONFIG_I2C_MUX) 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 606 #endif 607 return NULL; 608 } 609 610 int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)); 611 612 /* Adapter locking functions, exported for shared pin cases */ 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 { 625 adapter->lock_ops->lock_bus(adapter, flags); 626 } 627 628 /** 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 { 639 return adapter->lock_ops->trylock_bus(adapter, flags); 640 } 641 642 /** 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 { 651 adapter->lock_ops->unlock_bus(adapter, flags); 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 } 665 666 /*flags for the client struct: */ 667 #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ 668 #define I2C_CLIENT_TEN 0x10 /* we have a ten bit chip address */ 669 /* Must equal I2C_M_TEN below */ 670 #define I2C_CLIENT_SLAVE 0x20 /* we are the slave */ 671 #define I2C_CLIENT_HOST_NOTIFY 0x40 /* We want to use I2C host notify */ 672 #define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */ 673 #define I2C_CLIENT_SCCB 0x9000 /* Use Omnivision SCCB protocol */ 674 /* Must match I2C_M_STOP|IGNORE_NAK */ 675 676 /* i2c adapter classes (bitmask) */ 677 #define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ 678 #define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */ 679 #define I2C_CLASS_SPD (1<<7) /* Memory modules */ 680 #define I2C_CLASS_DEPRECATED (1<<8) /* Warn users that adapter will stop using classes */ 681 682 /* Internal numbers to terminate lists */ 683 #define I2C_CLIENT_END 0xfffeU 684 685 /* 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 }) 688 689 690 /* ----- functions exported by i2c.o */ 691 692 /* administration... 693 */ 694 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) 695 extern int i2c_add_adapter(struct i2c_adapter *); 696 extern void i2c_del_adapter(struct i2c_adapter *); 697 extern int i2c_add_numbered_adapter(struct i2c_adapter *); 698 699 extern int i2c_register_driver(struct module *, struct i2c_driver *); 700 extern void i2c_del_driver(struct i2c_driver *); 701 702 /* use a define to avoid include chaining to get THIS_MODULE */ 703 #define i2c_add_driver(driver) \ 704 i2c_register_driver(THIS_MODULE, driver) 705 706 extern struct i2c_client *i2c_use_client(struct i2c_client *client); 707 extern void i2c_release_client(struct i2c_client *client); 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); 713 714 extern struct i2c_adapter *i2c_get_adapter(int nr); 715 extern void i2c_put_adapter(struct i2c_adapter *adap); 716 extern unsigned int i2c_adapter_depth(struct i2c_adapter *adapter); 717 718 void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults); 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 } 731 732 /** 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 } 745 746 /* Return the adapter number for a specific adapter */ 747 static inline int i2c_adapter_id(struct i2c_adapter *adap) 748 { 749 return adap->nr; 750 } 751 752 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 } 756 757 int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr); 758 /** 759 * module_i2c_driver() - Helper macro for registering a modular I2C driver 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) 769 770 /** 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) 780 781 #endif /* I2C */ 782 783 #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); 789 790 /* 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); 792 793 extern const struct of_device_id 794 *i2c_of_match_device(const struct of_device_id *matches, 795 struct i2c_client *client); 796 797 #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 } 808 809 static inline struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) 810 { 811 return NULL; 812 } 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 } 820 821 #endif /* CONFIG_OF */ 822 823 #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 */ 831 832 #endif /* _LINUX_I2C_H */ 833