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 1.1.1.1 2005/04/11 02:51:02 jack 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 <linux/version.h>
46 #ifndef KERNEL_VERSION
47 #define KERNEL_VERSION(a,b,c) (((a) << 16) | ((b) << 8) | (c))
50 #include <asm/page.h> /* for 2.2.xx */
51 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,0,25)
52 #include <linux/sched.h>
54 #include <asm/semaphore.h>
56 #include <linux/config.h>
58 /* --- General options ------------------------------------------------ */
60 #define I2C_ALGO_MAX 4 /* control memory consumption */
61 #define I2C_ADAP_MAX 16
62 #define I2C_DRIVER_MAX 16
63 #define I2C_CLIENT_MAX 32
64 #define I2C_DUMMY_MAX 4
70 struct i2c_client_address_data;
75 * The master routines are the ones normally used to transmit data to devices
76 * on a bus (or read from them). Apart from two basic transfer functions to
77 * transmit one message at a time, a more complex version can be used to
78 * transmit an arbitrary number of messages without interruption.
80 extern int i2c_master_send(struct i2c_client *,const char* ,int);
81 extern int i2c_master_recv(struct i2c_client *,char* ,int);
83 /* Transfer num messages.
85 extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg msg[],int num);
88 * Some adapter types (i.e. PCF 8584 based ones) may support slave behaviuor.
89 * This is not tested/implemented yet and will change in the future.
91 extern int i2c_slave_send(struct i2c_client *,char*,int);
92 extern int i2c_slave_recv(struct i2c_client *,char*,int);
96 /* This is the very generalized SMBus access routine. You probably do not
97 want to use this, though; one of the functions below may be much easier,
98 and probably just as fast.
99 Note that we use i2c_adapter here, because you do not need a specific
100 smbus adapter to call this function. */
101 extern s32 i2c_smbus_xfer (struct i2c_adapter * adapter, u16 addr,
102 unsigned short flags,
103 char read_write, u8 command, int size,
104 union i2c_smbus_data * data);
106 /* Now follow the 'nice' access routines. These also document the calling
107 conventions of smbus_access. */
109 extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
110 extern s32 i2c_smbus_read_byte(struct i2c_client * client);
111 extern s32 i2c_smbus_write_byte(struct i2c_client * client, u8 value);
112 extern s32 i2c_smbus_read_byte_data(struct i2c_client * client, u8 command);
113 extern s32 i2c_smbus_write_byte_data(struct i2c_client * client,
114 u8 command, u8 value);
115 extern s32 i2c_smbus_read_word_data(struct i2c_client * client, u8 command);
116 extern s32 i2c_smbus_write_word_data(struct i2c_client * client,
117 u8 command, u16 value);
118 extern s32 i2c_smbus_process_call(struct i2c_client * client,
119 u8 command, u16 value);
120 /* Returns the number of read bytes */
121 extern s32 i2c_smbus_read_block_data(struct i2c_client * client,
122 u8 command, u8 *values);
123 extern s32 i2c_smbus_write_block_data(struct i2c_client * client,
124 u8 command, u8 length,
126 extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
127 u8 command, u8 length,
132 * A driver is capable of handling one or more physical devices present on
133 * I2C adapters. This information is used to inform the driver of adapter
140 unsigned int flags; /* div., see below */
142 /* Notifies the driver that a new bus has appeared. This routine
143 * can be used by the driver to test if the bus meets its conditions
144 * & seek for the presence of the chip(s) it supports. If found, it
145 * registers the client(s) that are on the bus to the i2c admin. via
148 int (*attach_adapter)(struct i2c_adapter *);
150 /* tells the driver that a client is about to be deleted & gives it
151 * the chance to remove its private data. Also, if the client struct
152 * has been dynamically allocated by the driver in the function above,
153 * it must be freed here.
155 int (*detach_client)(struct i2c_client *);
157 /* a ioctl like command that can be used to perform specific functions
160 int (*command)(struct i2c_client *client,unsigned int cmd, void *arg);
162 /* These two are mainly used for bookkeeping & dynamic unloading of
163 * kernel modules. inc_use tells the driver that a client is being
164 * used by another module & that it should increase its ref. counter.
165 * dec_use is the inverse operation.
166 * NB: Make sure you have no circular dependencies, or else you get a
167 * deadlock when trying to unload the modules.
168 * You should use the i2c_{inc,dec}_use_client functions instead of
169 * calling this function directly.
171 void (*inc_use)(struct i2c_client *client);
172 void (*dec_use)(struct i2c_client *client);
176 * i2c_client identifies a single device (i.e. chip) that is connected to an
177 * i2c bus. The behaviour is defined by the routines of the driver. This
178 * function is mainly used for lookup & other admin. functions.
183 unsigned int flags; /* div., see below */
184 unsigned int addr; /* chip address - NOTE: 7bit */
185 /* addresses are stored in the */
186 /* _LOWER_ 7 bits of this char */
187 /* addr: unsigned int to make lm_sensors i2c-isa adapter work
188 more cleanly. It does not take any more memory space, due to
189 alignment considerations */
190 struct i2c_adapter *adapter; /* the adapter we sit on */
191 struct i2c_driver *driver; /* and our access routines */
192 void *data; /* for the clients */
193 int usage_count; /* How many accesses currently */
199 * The following structs are for those who like to implement new bus drivers:
200 * i2c_algorithm is the interface to a class of hardware solutions which can
201 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
202 * to name two of the most common.
204 struct i2c_algorithm {
205 char name[32]; /* textual description */
208 /* If an adapter algorithm can't to I2C-level access, set master_xfer
209 to NULL. If an adapter algorithm can do SMBus access, set
210 smbus_xfer. If set to NULL, the SMBus protocol is simulated
211 using common I2C messages */
212 int (*master_xfer)(struct i2c_adapter *adap,struct i2c_msg msgs[],
214 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
215 unsigned short flags, char read_write,
216 u8 command, int size, union i2c_smbus_data * data);
218 /* --- these optional/future use for some adapter types.*/
219 int (*slave_send)(struct i2c_adapter *,char*,int);
220 int (*slave_recv)(struct i2c_adapter *,char*,int);
222 /* --- ioctl like call to set div. parameters. */
223 int (*algo_control)(struct i2c_adapter *, unsigned int, unsigned long);
225 /* To determine what the adapter supports */
226 u32 (*functionality) (struct i2c_adapter *);
229 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,1,29)
230 struct proc_dir_entry;
234 * i2c_adapter is the structure used to identify a physical i2c bus along
235 * with the access algorithms necessary to access it.
238 char name[32]; /* some useful name to identify the adapter */
239 unsigned int id;/* == is algo->id | hwdep.struct->id, */
240 /* for registered values see below */
241 struct i2c_algorithm *algo;/* the algorithm to access the bus */
244 /* --- These may be NULL, but should increase the module use count */
245 void (*inc_use)(struct i2c_adapter *);
246 void (*dec_use)(struct i2c_adapter *);
248 /* --- administration stuff. */
249 int (*client_register)(struct i2c_client *);
250 int (*client_unregister)(struct i2c_client *);
252 void *data; /* private data for the adapter */
253 /* some data fields that are used by all types */
254 /* these data fields are readonly to the public */
255 /* and can be set via the i2c_ioctl call */
257 /* data fields that are valid for all devices */
258 struct semaphore lock;
259 unsigned int flags;/* flags specifying div. data */
261 struct i2c_client *clients[I2C_CLIENT_MAX];
267 #ifdef CONFIG_PROC_FS
268 /* No need to set this when you initialize the adapter */
270 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,1,29)
271 struct proc_dir_entry *proc_entry;
273 #endif /* def CONFIG_PROC_FS */
276 /*flags for the driver struct: */
277 #define I2C_DF_NOTIFY 0x01 /* notify on bus (de/a)ttaches */
278 #define I2C_DF_DUMMY 0x02 /* do not connect any clients */
280 /*flags for the client struct: */
281 #define I2C_CLIENT_ALLOW_USE 0x01 /* Client allows access */
282 #define I2C_CLIENT_ALLOW_MULTIPLE_USE 0x02 /* Allow multiple access-locks */
283 /* on an i2c_client */
285 /* i2c_client_address_data is the struct for holding default client
286 * addresses for a driver and for the parameters supplied on the
289 struct i2c_client_address_data {
290 unsigned short *normal_i2c;
291 unsigned short *normal_i2c_range;
292 unsigned short *probe;
293 unsigned short *probe_range;
294 unsigned short *ignore;
295 unsigned short *ignore_range;
296 unsigned short *force;
299 /* Internal numbers to terminate lists */
300 #define I2C_CLIENT_END 0xfffe
302 /* The numbers to use to set I2C bus address */
303 #define ANY_I2C_BUS 0xffff
305 /* The length of the option lists */
306 #define I2C_CLIENT_MAX_OPTS 48
309 /* ----- functions exported by i2c.o */
313 extern int i2c_add_adapter(struct i2c_adapter *);
314 extern int i2c_del_adapter(struct i2c_adapter *);
316 extern int i2c_add_driver(struct i2c_driver *);
317 extern int i2c_del_driver(struct i2c_driver *);
319 extern int i2c_attach_client(struct i2c_client *);
320 extern int i2c_detach_client(struct i2c_client *);
322 /* Only call these if you grab a resource that makes unloading the
323 client and the adapter it is on completely impossible. Like when a
324 /proc directory is entered. */
325 extern void i2c_inc_use_client(struct i2c_client *);
326 extern void i2c_dec_use_client(struct i2c_client *);
328 /* New function: This is to get an i2c_client-struct for controlling the
329 client either by using i2c_control-function or having the
330 client-module export functions that can be used with the i2c_client
332 extern struct i2c_client *i2c_get_client(int driver_id, int adapter_id,
333 struct i2c_client *prev);
335 /* Should be used with new function
336 extern struct i2c_client *i2c_get_client(int,int,struct i2c_client *);
337 to make sure that client-struct is valid and that it is okay to access
339 returns -EACCES if client doesn't allow use (default)
340 returns -EBUSY if client doesn't allow multiple use (default) and
342 extern int i2c_use_client(struct i2c_client *);
343 extern int i2c_release_client(struct i2c_client *);
345 /* returns -EBUSY if address has been taken, 0 if not. Note that the only
346 other place at which this is called is within i2c_attach_client; so
347 you can cheat by simply not registering. Not recommended, of course! */
348 extern int i2c_check_addr (struct i2c_adapter *adapter, int addr);
350 /* Detect function. It iterates over all possible addresses itself.
351 * It will only call found_proc if some client is connected at the
352 * specific address (unless a 'force' matched);
354 typedef int i2c_client_found_addr_proc (struct i2c_adapter *adapter,
355 int addr, unsigned short flags,int kind);
357 extern int i2c_probe(struct i2c_adapter *adapter,
358 struct i2c_client_address_data *address_data,
359 i2c_client_found_addr_proc *found_proc);
361 /* An ioctl like call to set div. parameters of the adapter.
363 extern int i2c_control(struct i2c_client *,unsigned int, unsigned long);
365 /* This call returns a unique low identifier for each registered adapter,
366 * or -1 if the adapter was not registered.
368 extern int i2c_adapter_id(struct i2c_adapter *adap);
372 /* Return the functionality mask */
373 extern u32 i2c_get_functionality (struct i2c_adapter *adap);
375 /* Return 1 if adapter supports everything we need, 0 if not. */
376 extern int i2c_check_functionality (struct i2c_adapter *adap, u32 func);
378 #endif /* __KERNEL__ */
381 * I2C Message - used for pure i2c transaction, also from /dev interface
384 __u16 addr; /* slave address */
385 unsigned short flags;
386 #define I2C_M_TEN 0x10 /* we have a ten bit chip address */
387 #define I2C_M_RD 0x01
388 #define I2C_M_NOSTART 0x4000
389 #define I2C_M_REV_DIR_ADDR 0x2000
390 short len; /* msg length */
391 char *buf; /* pointer to msg data */
394 /* To determine what functionality is present */
396 #define I2C_FUNC_I2C 0x00000001
397 #define I2C_FUNC_10BIT_ADDR 0x00000002
398 #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_{REV_DIR_ADDR,NOSTART} */
399 #define I2C_FUNC_SMBUS_QUICK 0x00010000
400 #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
401 #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
402 #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
403 #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
404 #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
405 #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
406 #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
407 #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
408 #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
409 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* New I2C-like block */
410 #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* transfer */
412 #define I2C_FUNC_SMBUS_BYTE I2C_FUNC_SMBUS_READ_BYTE | \
413 I2C_FUNC_SMBUS_WRITE_BYTE
414 #define I2C_FUNC_SMBUS_BYTE_DATA I2C_FUNC_SMBUS_READ_BYTE_DATA | \
415 I2C_FUNC_SMBUS_WRITE_BYTE_DATA
416 #define I2C_FUNC_SMBUS_WORD_DATA I2C_FUNC_SMBUS_READ_WORD_DATA | \
417 I2C_FUNC_SMBUS_WRITE_WORD_DATA
418 #define I2C_FUNC_SMBUS_BLOCK_DATA I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
419 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
420 #define I2C_FUNC_SMBUS_I2C_BLOCK I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
421 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK
423 #define I2C_FUNC_SMBUS_EMUL I2C_FUNC_SMBUS_QUICK | \
424 I2C_FUNC_SMBUS_BYTE | \
425 I2C_FUNC_SMBUS_BYTE_DATA | \
426 I2C_FUNC_SMBUS_WORD_DATA | \
427 I2C_FUNC_SMBUS_PROC_CALL | \
428 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
431 * Data for SMBus Messages
433 union i2c_smbus_data {
436 __u8 block[33]; /* block[0] is used for length */
439 /* smbus_access read or write markers */
440 #define I2C_SMBUS_READ 1
441 #define I2C_SMBUS_WRITE 0
443 /* SMBus transaction types (size parameter in the above functions)
444 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
445 #define I2C_SMBUS_QUICK 0
446 #define I2C_SMBUS_BYTE 1
447 #define I2C_SMBUS_BYTE_DATA 2
448 #define I2C_SMBUS_WORD_DATA 3
449 #define I2C_SMBUS_PROC_CALL 4
450 #define I2C_SMBUS_BLOCK_DATA 5
451 #define I2C_SMBUS_I2C_BLOCK_DATA 6
454 /* ----- commands for the ioctl like i2c_command call:
455 * note that additional calls are defined in the algorithm and hw
456 * dependent layers - these can be listed here, or see the
457 * corresponding header files.
459 /* -> bit-adapter specific ioctls */
460 #define I2C_RETRIES 0x0701 /* number of times a device address */
461 /* should be polled when not */
463 #define I2C_TIMEOUT 0x0702 /* set timeout - call with int */
466 /* this is for i2c-dev.c */
467 #define I2C_SLAVE 0x0703 /* Change slave address */
468 /* Attn.: Slave address is 7 or 10 bits */
469 #define I2C_SLAVE_FORCE 0x0706 /* Change slave address */
470 /* Attn.: Slave address is 7 or 10 bits */
471 /* This changes the address, even if it */
472 /* is already taken! */
473 #define I2C_TENBIT 0x0704 /* 0 for 7 bit addrs, != 0 for 10 bit */
475 #define I2C_FUNCS 0x0705 /* Get the adapter functionality */
476 #define I2C_RDWR 0x0707 /* Combined R/W transfer (one stop only)*/
478 #define I2C_ACK_TEST 0x0710 /* See if a slave is at a specific address */
481 #define I2C_SMBUS 0x0720 /* SMBus-level access */
483 /* ... algo-bit.c recognizes */
484 #define I2C_UDELAY 0x0705 /* set delay in microsecs between each */
485 /* written byte (except address) */
486 #define I2C_MDELAY 0x0706 /* millisec delay between written bytes */
488 /* ----- I2C-DEV: char device interface stuff ------------------------- */
490 #define I2C_MAJOR 89 /* Device major number */
495 # define NULL ( (void *) 0 )
499 # include <asm/errno.h>
502 /* These defines are used for probing i2c client addresses */
503 /* Default fill of many variables */
504 #define I2C_CLIENT_DEFAULTS {I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
505 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
506 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
507 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
508 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
509 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
510 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
511 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
512 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
513 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
514 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
515 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
516 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
517 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
518 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
519 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END}
521 /* This is ugly. We need to evaluate I2C_CLIENT_MAX_OPTS before it is
523 #define I2C_CLIENT_MODPARM_AUX1(x) "1-" #x "h"
524 #define I2C_CLIENT_MODPARM_AUX(x) I2C_CLIENT_MODPARM_AUX1(x)
525 #define I2C_CLIENT_MODPARM I2C_CLIENT_MODPARM_AUX(I2C_CLIENT_MAX_OPTS)
527 /* I2C_CLIENT_MODULE_PARM creates a module parameter, and puts it in the
530 #define I2C_CLIENT_MODULE_PARM(var,desc) \
531 static unsigned short var[I2C_CLIENT_MAX_OPTS] = I2C_CLIENT_DEFAULTS; \
532 MODULE_PARM(var,I2C_CLIENT_MODPARM); \
533 MODULE_PARM_DESC(var,desc)
535 /* This is the one you want to use in your own modules */
536 #define I2C_CLIENT_INSMOD \
537 I2C_CLIENT_MODULE_PARM(probe, \
538 "List of adapter,address pairs to scan additionally"); \
539 I2C_CLIENT_MODULE_PARM(probe_range, \
540 "List of adapter,start-addr,end-addr triples to scan " \
542 I2C_CLIENT_MODULE_PARM(ignore, \
543 "List of adapter,address pairs not to scan"); \
544 I2C_CLIENT_MODULE_PARM(ignore_range, \
545 "List of adapter,start-addr,end-addr triples not to " \
547 I2C_CLIENT_MODULE_PARM(force, \
548 "List of adapter,address pairs to boldly assume " \
550 static struct i2c_client_address_data addr_data = \
551 {normal_i2c, normal_i2c_range, \
552 probe, probe_range, \
553 ignore, ignore_range, \
556 /* Detect whether we are on the isa bus. If this returns true, all i2c
558 #define i2c_is_isa_client(clientptr) \
559 ((clientptr)->adapter->algo->id == I2C_ALGO_ISA)
560 #define i2c_is_isa_adapter(adapptr) \
561 ((adapptr)->algo->id == I2C_ALGO_ISA)
563 #endif /* def __KERNEL__ */