1 /* ------------------------------------------------------------------------- */
3 /* i2c.h - definitions for the i2c-bus interface */
5 /* ------------------------------------------------------------------------- */
6 /* Copyright (C) 1995-2000 Simon G. Vogl
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.
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.
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., 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* ------------------------------------------------------------------------- */
23 /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
24 Frodo Looijaard <frodol@dds.nl> */
26 /* $Id: i2c.h,v 1.46 2001/08/31 00:04:07 phil Exp $ */
31 #define I2C_DATE "20010830"
32 #define I2C_VERSION "2.6.1"
34 #include <linux/i2c-id.h> /* id values of adapters et. al. */
35 #include <linux/types.h>
43 /* --- Includes and compatibility declarations ------------------------ */
45 #include <asm/semaphore.h>
46 #include <linux/config.h>
48 /* --- General options ------------------------------------------------ */
50 #define I2C_ADAP_MAX 16 /* control memory consumption */
51 #define I2C_DRIVER_MAX 16
52 #define I2C_CLIENT_MAX 32
58 struct i2c_client_address_data;
63 * The master routines are the ones normally used to transmit data to devices
64 * on a bus (or read from them). Apart from two basic transfer functions to
65 * transmit one message at a time, a more complex version can be used to
66 * transmit an arbitrary number of messages without interruption.
68 extern int i2c_master_send(struct i2c_client *,const char* ,int);
69 extern int i2c_master_recv(struct i2c_client *,char* ,int);
71 /* Transfer num messages.
73 extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msg,int num);
76 /* This is the very generalized SMBus access routine. You probably do not
77 want to use this, though; one of the functions below may be much easier,
78 and probably just as fast.
79 Note that we use i2c_adapter here, because you do not need a specific
80 smbus adapter to call this function. */
81 extern s32 i2c_smbus_xfer (struct i2c_adapter * adapter, u16 addr,
83 char read_write, u8 command, int size,
84 union i2c_smbus_data * data);
86 /* Now follow the 'nice' access routines. These also document the calling
87 conventions of smbus_access. */
89 extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
90 extern s32 i2c_smbus_read_byte(struct i2c_client * client);
91 extern s32 i2c_smbus_write_byte(struct i2c_client * client, u8 value);
92 extern s32 i2c_smbus_read_byte_data(struct i2c_client * client, u8 command);
93 extern s32 i2c_smbus_write_byte_data(struct i2c_client * client,
94 u8 command, u8 value);
95 extern s32 i2c_smbus_read_word_data(struct i2c_client * client, u8 command);
96 extern s32 i2c_smbus_write_word_data(struct i2c_client * client,
97 u8 command, u16 value);
98 extern s32 i2c_smbus_process_call(struct i2c_client * client,
99 u8 command, u16 value);
100 /* Returns the number of read bytes */
101 extern s32 i2c_smbus_read_block_data(struct i2c_client * client,
102 u8 command, u8 *values);
103 extern s32 i2c_smbus_write_block_data(struct i2c_client * client,
104 u8 command, u8 length,
106 extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
107 u8 command, u8 length,
112 * A driver is capable of handling one or more physical devices present on
113 * I2C adapters. This information is used to inform the driver of adapter
120 unsigned int flags; /* div., see below */
122 /* Notifies the driver that a new bus has appeared. This routine
123 * can be used by the driver to test if the bus meets its conditions
124 * & seek for the presence of the chip(s) it supports. If found, it
125 * registers the client(s) that are on the bus to the i2c admin. via
128 int (*attach_adapter)(struct i2c_adapter *);
130 /* tells the driver that a client is about to be deleted & gives it
131 * the chance to remove its private data. Also, if the client struct
132 * has been dynamically allocated by the driver in the function above,
133 * it must be freed here.
135 int (*detach_client)(struct i2c_client *);
137 /* a ioctl like command that can be used to perform specific functions
140 int (*command)(struct i2c_client *client,unsigned int cmd, void *arg);
142 /* These two are used for bookkeeping & dynamic unloading of
143 * kernel modules. inc_use tells the driver that a client is being
144 * used by another module & that it should increase its ref. counter.
145 * dec_use is the inverse operation.
146 * NB: Make sure you have no circular dependencies, or else you get a
147 * deadlock when trying to unload the modules.
148 * You should use the i2c_{inc,dec}_use_client functions instead of
149 * calling this function directly.
151 void (*inc_use)(struct i2c_client *client);
152 void (*dec_use)(struct i2c_client *client);
156 * i2c_client identifies a single device (i.e. chip) that is connected to an
157 * i2c bus. The behaviour is defined by the routines of the driver. This
158 * function is mainly used for lookup & other admin. functions.
163 unsigned int flags; /* div., see below */
164 unsigned int addr; /* chip address - NOTE: 7bit */
165 /* addresses are stored in the */
166 /* _LOWER_ 7 bits of this char */
167 /* addr: unsigned int to make lm_sensors i2c-isa adapter work
168 more cleanly. It does not take any more memory space, due to
169 alignment considerations */
170 struct i2c_adapter *adapter; /* the adapter we sit on */
171 struct i2c_driver *driver; /* and our access routines */
172 void *data; /* for the clients */
173 int usage_count; /* How many accesses currently */
179 * The following structs are for those who like to implement new bus drivers:
180 * i2c_algorithm is the interface to a class of hardware solutions which can
181 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
182 * to name two of the most common.
184 struct i2c_algorithm {
185 char name[32]; /* textual description */
188 /* If an adapter algorithm can't do I2C-level access, set master_xfer
189 to NULL. If an adapter algorithm can do SMBus access, set
190 smbus_xfer. If set to NULL, the SMBus protocol is simulated
191 using common I2C messages */
192 int (*master_xfer)(struct i2c_adapter *adap,struct i2c_msg *msgs,
194 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
195 unsigned short flags, char read_write,
196 u8 command, int size, union i2c_smbus_data * data);
198 /* --- these optional/future use for some adapter types.*/
199 int (*slave_send)(struct i2c_adapter *,char*,int);
200 int (*slave_recv)(struct i2c_adapter *,char*,int);
202 /* --- ioctl like call to set div. parameters. */
203 int (*algo_control)(struct i2c_adapter *, unsigned int, unsigned long);
205 /* To determine what the adapter supports */
206 u32 (*functionality) (struct i2c_adapter *);
210 * i2c_adapter is the structure used to identify a physical i2c bus along
211 * with the access algorithms necessary to access it.
214 char name[32]; /* some useful name to identify the adapter */
215 unsigned int id;/* == is algo->id | hwdep.struct->id, */
216 /* for registered values see below */
217 struct i2c_algorithm *algo;/* the algorithm to access the bus */
220 /* --- These may be NULL, but should increase the module use count */
221 void (*inc_use)(struct i2c_adapter *);
222 void (*dec_use)(struct i2c_adapter *);
224 /* --- administration stuff. */
225 int (*client_register)(struct i2c_client *);
226 int (*client_unregister)(struct i2c_client *);
228 void *data; /* private data for the adapter */
229 /* some data fields that are used by all types */
230 /* these data fields are readonly to the public */
231 /* and can be set via the i2c_ioctl call */
233 /* data fields that are valid for all devices */
234 struct semaphore lock;
235 unsigned int flags;/* flags specifying div. data */
237 struct i2c_client *clients[I2C_CLIENT_MAX];
243 #ifdef CONFIG_PROC_FS
244 /* No need to set this when you initialize the adapter */
246 #endif /* def CONFIG_PROC_FS */
249 /*flags for the driver struct: */
250 #define I2C_DF_NOTIFY 0x01 /* notify on bus (de/a)ttaches */
251 #define I2C_DF_DUMMY 0x02 /* do not connect any clients */
253 /*flags for the client struct: */
254 #define I2C_CLIENT_ALLOW_USE 0x01 /* Client allows access */
255 #define I2C_CLIENT_ALLOW_MULTIPLE_USE 0x02 /* Allow multiple access-locks */
256 /* on an i2c_client */
258 /* i2c_client_address_data is the struct for holding default client
259 * addresses for a driver and for the parameters supplied on the
262 struct i2c_client_address_data {
263 unsigned short *normal_i2c;
264 unsigned short *normal_i2c_range;
265 unsigned short *probe;
266 unsigned short *probe_range;
267 unsigned short *ignore;
268 unsigned short *ignore_range;
269 unsigned short *force;
272 /* Internal numbers to terminate lists */
273 #define I2C_CLIENT_END 0xfffe
275 /* The numbers to use to set I2C bus address */
276 #define ANY_I2C_BUS 0xffff
278 /* The length of the option lists */
279 #define I2C_CLIENT_MAX_OPTS 48
282 /* ----- functions exported by i2c.o */
286 extern int i2c_add_adapter(struct i2c_adapter *);
287 extern int i2c_del_adapter(struct i2c_adapter *);
289 extern int i2c_add_driver(struct i2c_driver *);
290 extern int i2c_del_driver(struct i2c_driver *);
292 extern int i2c_attach_client(struct i2c_client *);
293 extern int i2c_detach_client(struct i2c_client *);
295 /* Only call these if you grab a resource that makes unloading the
296 client and the adapter it is on completely impossible. Like when a
297 /proc directory is entered. */
298 extern void i2c_inc_use_client(struct i2c_client *);
299 extern void i2c_dec_use_client(struct i2c_client *);
301 /* New function: This is to get an i2c_client-struct for controlling the
302 client either by using i2c_control-function or having the
303 client-module export functions that can be used with the i2c_client
305 extern struct i2c_client *i2c_get_client(int driver_id, int adapter_id,
306 struct i2c_client *prev);
308 /* Should be used with new function
309 extern struct i2c_client *i2c_get_client(int,int,struct i2c_client *);
310 to make sure that client-struct is valid and that it is okay to access
312 returns -EACCES if client doesn't allow use (default)
313 returns -EBUSY if client doesn't allow multiple use (default) and
315 extern int i2c_use_client(struct i2c_client *);
316 extern int i2c_release_client(struct i2c_client *);
318 /* returns -EBUSY if address has been taken, 0 if not. Note that the only
319 other place at which this is called is within i2c_attach_client; so
320 you can cheat by simply not registering. Not recommended, of course! */
321 extern int i2c_check_addr (struct i2c_adapter *adapter, int addr);
323 /* Detect function. It iterates over all possible addresses itself.
324 * It will only call found_proc if some client is connected at the
325 * specific address (unless a 'force' matched);
327 typedef int i2c_client_found_addr_proc (struct i2c_adapter *adapter,
328 int addr, unsigned short flags,int kind);
330 extern int i2c_probe(struct i2c_adapter *adapter,
331 struct i2c_client_address_data *address_data,
332 i2c_client_found_addr_proc *found_proc);
334 /* An ioctl like call to set div. parameters of the adapter.
336 extern int i2c_control(struct i2c_client *,unsigned int, unsigned long);
338 /* This call returns a unique low identifier for each registered adapter,
339 * or -1 if the adapter was not registered.
341 extern int i2c_adapter_id(struct i2c_adapter *adap);
345 /* Return the functionality mask */
346 extern u32 i2c_get_functionality (struct i2c_adapter *adap);
348 /* Return 1 if adapter supports everything we need, 0 if not. */
349 extern int i2c_check_functionality (struct i2c_adapter *adap, u32 func);
351 #endif /* __KERNEL__ */
354 * I2C Message - used for pure i2c transaction, also from /dev interface
357 __u16 addr; /* slave address */
359 #define I2C_M_TEN 0x10 /* we have a ten bit chip address */
360 #define I2C_M_RD 0x01
361 #define I2C_M_NOSTART 0x4000
362 #define I2C_M_REV_DIR_ADDR 0x2000
363 __u16 len; /* msg length */
364 __u8 *buf; /* pointer to msg data */
367 /* To determine what functionality is present */
369 #define I2C_FUNC_I2C 0x00000001
370 #define I2C_FUNC_10BIT_ADDR 0x00000002
371 #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_{REV_DIR_ADDR,NOSTART} */
372 #define I2C_FUNC_SMBUS_QUICK 0x00010000
373 #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
374 #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
375 #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
376 #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
377 #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
378 #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
379 #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
380 #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
381 #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
382 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* New I2C-like block */
383 #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* transfer */
385 #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \
386 I2C_FUNC_SMBUS_WRITE_BYTE)
387 #define I2C_FUNC_SMBUS_BYTE_DATA (I2C_FUNC_SMBUS_READ_BYTE_DATA | \
388 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
389 #define I2C_FUNC_SMBUS_WORD_DATA (I2C_FUNC_SMBUS_READ_WORD_DATA | \
390 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
391 #define I2C_FUNC_SMBUS_BLOCK_DATA (I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
392 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
393 #define I2C_FUNC_SMBUS_I2C_BLOCK (I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
394 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)
396 #define I2C_FUNC_SMBUS_EMUL (I2C_FUNC_SMBUS_QUICK | \
397 I2C_FUNC_SMBUS_BYTE | \
398 I2C_FUNC_SMBUS_BYTE_DATA | \
399 I2C_FUNC_SMBUS_WORD_DATA | \
400 I2C_FUNC_SMBUS_PROC_CALL | \
401 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
404 * Data for SMBus Messages
406 #define I2C_SMBUS_BLOCK_MAX 32 /* As specified in SMBus standard */
407 #define I2C_SMBUS_I2C_BLOCK_MAX 32 /* Not specified but we use same structure */
408 union i2c_smbus_data {
411 __u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
412 /* one more for read length in block process call */
415 /* smbus_access read or write markers */
416 #define I2C_SMBUS_READ 1
417 #define I2C_SMBUS_WRITE 0
419 /* SMBus transaction types (size parameter in the above functions)
420 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
421 #define I2C_SMBUS_QUICK 0
422 #define I2C_SMBUS_BYTE 1
423 #define I2C_SMBUS_BYTE_DATA 2
424 #define I2C_SMBUS_WORD_DATA 3
425 #define I2C_SMBUS_PROC_CALL 4
426 #define I2C_SMBUS_BLOCK_DATA 5
427 #define I2C_SMBUS_I2C_BLOCK_DATA 6
430 /* ----- commands for the ioctl like i2c_command call:
431 * note that additional calls are defined in the algorithm and hw
432 * dependent layers - these can be listed here, or see the
433 * corresponding header files.
435 /* -> bit-adapter specific ioctls */
436 #define I2C_RETRIES 0x0701 /* number of times a device address */
437 /* should be polled when not */
439 #define I2C_TIMEOUT 0x0702 /* set timeout - call with int */
442 /* this is for i2c-dev.c */
443 #define I2C_SLAVE 0x0703 /* Change slave address */
444 /* Attn.: Slave address is 7 or 10 bits */
445 #define I2C_SLAVE_FORCE 0x0706 /* Change slave address */
446 /* Attn.: Slave address is 7 or 10 bits */
447 /* This changes the address, even if it */
448 /* is already taken! */
449 #define I2C_TENBIT 0x0704 /* 0 for 7 bit addrs, != 0 for 10 bit */
451 #define I2C_FUNCS 0x0705 /* Get the adapter functionality */
452 #define I2C_RDWR 0x0707 /* Combined R/W transfer (one stop only)*/
454 #define I2C_SMBUS 0x0720 /* SMBus-level access */
456 /* ----- I2C-DEV: char device interface stuff ------------------------- */
458 #define I2C_MAJOR 89 /* Device major number */
463 # define NULL ( (void *) 0 )
467 # include <asm/errno.h>
470 /* These defines are used for probing i2c client addresses */
471 /* Default fill of many variables */
472 #define I2C_CLIENT_DEFAULTS {I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
473 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
474 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
475 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
476 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
477 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
478 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
479 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
480 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
481 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
482 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
483 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
484 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
485 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
486 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
487 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END}
489 /* This is ugly. We need to evaluate I2C_CLIENT_MAX_OPTS before it is
491 #define I2C_CLIENT_MODPARM_AUX1(x) "1-" #x "h"
492 #define I2C_CLIENT_MODPARM_AUX(x) I2C_CLIENT_MODPARM_AUX1(x)
493 #define I2C_CLIENT_MODPARM I2C_CLIENT_MODPARM_AUX(I2C_CLIENT_MAX_OPTS)
495 /* I2C_CLIENT_MODULE_PARM creates a module parameter, and puts it in the
498 #define I2C_CLIENT_MODULE_PARM(var,desc) \
499 static unsigned short var[I2C_CLIENT_MAX_OPTS] = I2C_CLIENT_DEFAULTS; \
500 MODULE_PARM(var,I2C_CLIENT_MODPARM); \
501 MODULE_PARM_DESC(var,desc)
503 /* This is the one you want to use in your own modules */
504 #define I2C_CLIENT_INSMOD \
505 I2C_CLIENT_MODULE_PARM(probe, \
506 "List of adapter,address pairs to scan additionally"); \
507 I2C_CLIENT_MODULE_PARM(probe_range, \
508 "List of adapter,start-addr,end-addr triples to scan " \
510 I2C_CLIENT_MODULE_PARM(ignore, \
511 "List of adapter,address pairs not to scan"); \
512 I2C_CLIENT_MODULE_PARM(ignore_range, \
513 "List of adapter,start-addr,end-addr triples not to " \
515 I2C_CLIENT_MODULE_PARM(force, \
516 "List of adapter,address pairs to boldly assume " \
518 static struct i2c_client_address_data addr_data = \
519 {normal_i2c, normal_i2c_range, \
520 probe, probe_range, \
521 ignore, ignore_range, \
524 /* Detect whether we are on the isa bus. If this returns true, all i2c
526 #define i2c_is_isa_client(clientptr) \
527 ((clientptr)->adapter->algo->id == I2C_ALGO_ISA)
528 #define i2c_is_isa_adapter(adapptr) \
529 ((adapptr)->algo->id == I2C_ALGO_ISA)
531 #endif /* def __KERNEL__ */