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., 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* ------------------------------------------------------------------------- */
22
23 /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
24 Frodo Looijaard <frodol@dds.nl> */
25
26 /* $Id: i2c.h,v 1.42 2000/09/06 20:14:06 frodo Exp $ */
27
28 #ifndef I2C_H
29 #define I2C_H
30
31 #include <linux/i2c-id.h> /* id values of adapters et. al. */
32 #include <linux/types.h>
33
34
35 struct i2c_msg;
36
37
38 #ifdef __KERNEL__
39
40 /* --- Includes and compatibility declarations ------------------------ */
41
42 #include <linux/version.h>
43 #ifndef KERNEL_VERSION
44 #define KERNEL_VERSION(a,b,c) (((a) << 16) | ((b) << 8) | (c))
45 #endif
46
47 #include <asm/page.h> /* for 2.2.xx */
48 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,0,25)
49 #include <linux/sched.h>
50 #else
51 #include <asm/semaphore.h>
52 #endif
53 #include <linux/config.h>
54
55 /* --- General options ------------------------------------------------ */
56
57 #define I2C_ALGO_MAX 4 /* control memory consumption */
58 #define I2C_ADAP_MAX 16
59 #define I2C_DRIVER_MAX 16
60 #define I2C_CLIENT_MAX 32
61 #define I2C_DUMMY_MAX 4
62
63 struct i2c_algorithm;
64 struct i2c_adapter;
65 struct i2c_client;
66 struct i2c_driver;
67 struct i2c_client_address_data;
68 union i2c_smbus_data;
69
70
71 /*
72 * The master routines are the ones normally used to transmit data to devices
73 * on a bus (or read from them). Apart from two basic transfer functions to
74 * transmit one message at a time, a more complex version can be used to
75 * transmit an arbitrary number of messages without interruption.
76 */
77 extern int i2c_master_send(struct i2c_client *,const char* ,int);
78 extern int i2c_master_recv(struct i2c_client *,char* ,int);
79
80 /* Transfer num messages.
81 */
82 extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg msg[],int num);
83
84 /*
85 * Some adapter types (i.e. PCF 8584 based ones) may support slave behaviuor.
86 * This is not tested/implemented yet and will change in the future.
87 */
88 extern int i2c_slave_send(struct i2c_client *,char*,int);
89 extern int i2c_slave_recv(struct i2c_client *,char*,int);
90
91
92
93 /* This is the very generalized SMBus access routine. You probably do not
94 want to use this, though; one of the functions below may be much easier,
95 and probably just as fast.
96 Note that we use i2c_adapter here, because you do not need a specific
97 smbus adapter to call this function. */
98 extern s32 i2c_smbus_xfer (struct i2c_adapter * adapter, u16 addr,
99 unsigned short flags,
100 char read_write, u8 command, int size,
101 union i2c_smbus_data * data);
102
103 /* Now follow the 'nice' access routines. These also document the calling
104 conventions of smbus_access. */
105
106 extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
107 extern s32 i2c_smbus_read_byte(struct i2c_client * client);
108 extern s32 i2c_smbus_write_byte(struct i2c_client * client, u8 value);
109 extern s32 i2c_smbus_read_byte_data(struct i2c_client * client, u8 command);
110 extern s32 i2c_smbus_write_byte_data(struct i2c_client * client,
111 u8 command, u8 value);
112 extern s32 i2c_smbus_read_word_data(struct i2c_client * client, u8 command);
113 extern s32 i2c_smbus_write_word_data(struct i2c_client * client,
114 u8 command, u16 value);
115 extern s32 i2c_smbus_process_call(struct i2c_client * client,
116 u8 command, u16 value);
117 /* Returns the number of read bytes */
118 extern s32 i2c_smbus_read_block_data(struct i2c_client * client,
119 u8 command, u8 *values);
120 extern s32 i2c_smbus_write_block_data(struct i2c_client * client,
121 u8 command, u8 length,
122 u8 *values);
123 extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
124 u8 command, u8 length,
125 u8 *values);
126
127
128 /*
129 * A driver is capable of handling one or more physical devices present on
130 * I2C adapters. This information is used to inform the driver of adapter
131 * events.
132 */
133
134 struct i2c_driver {
135 char name[32];
136 int id;
137 unsigned int flags; /* div., see below */
138
139 /* Notifies the driver that a new bus has appeared. This routine
140 * can be used by the driver to test if the bus meets its conditions
141 * & seek for the presence of the chip(s) it supports. If found, it
142 * registers the client(s) that are on the bus to the i2c admin. via
143 * i2c_attach_client.
144 */
145 int (*attach_adapter)(struct i2c_adapter *);
146
147 /* tells the driver that a client is about to be deleted & gives it
148 * the chance to remove its private data. Also, if the client struct
149 * has been dynamically allocated by the driver in the function above,
150 * it must be freed here.
151 */
152 int (*detach_client)(struct i2c_client *);
153
154 /* a ioctl like command that can be used to perform specific functions
155 * with the device.
156 */
157 int (*command)(struct i2c_client *client,unsigned int cmd, void *arg);
158
159 /* These two are mainly used for bookkeeping & dynamic unloading of
160 * kernel modules. inc_use tells the driver that a client is being
161 * used by another module & that it should increase its ref. counter.
162 * dec_use is the inverse operation.
163 * NB: Make sure you have no circular dependencies, or else you get a
164 * deadlock when trying to unload the modules.
165 * You should use the i2c_{inc,dec}_use_client functions instead of
166 * calling this function directly.
167 */
168 void (*inc_use)(struct i2c_client *client);
169 void (*dec_use)(struct i2c_client *client);
170 };
171
172 /*
173 * i2c_client identifies a single device (i.e. chip) that is connected to an
174 * i2c bus. The behaviour is defined by the routines of the driver. This
175 * function is mainly used for lookup & other admin. functions.
176 */
177 struct i2c_client {
178 char name[32];
179 int id;
180 unsigned int flags; /* div., see below */
181 unsigned int addr; /* chip address - NOTE: 7bit */
182 /* addresses are stored in the */
183 /* _LOWER_ 7 bits of this char */
184 /* addr: unsigned int to make lm_sensors i2c-isa adapter work
185 more cleanly. It does not take any more memory space, due to
186 alignment considerations */
187 struct i2c_adapter *adapter; /* the adapter we sit on */
188 struct i2c_driver *driver; /* and our access routines */
189 void *data; /* for the clients */
190 int usage_count; /* How many accesses currently */
191 /* to the client */
192 };
193
194
195 /*
196 * The following structs are for those who like to implement new bus drivers:
197 * i2c_algorithm is the interface to a class of hardware solutions which can
198 * be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
199 * to name two of the most common.
200 */
201 struct i2c_algorithm {
202 char name[32]; /* textual description */
203 unsigned int id;
204
205 /* If a adapter algorithm can't to I2C-level access, set master_xfer
206 to NULL. If an adapter algorithm can do SMBus access, set
207 smbus_xfer. If set to NULL, the SMBus protocol is simulated
208 using common I2C messages */
209 int (*master_xfer)(struct i2c_adapter *adap,struct i2c_msg msgs[],
210 int num);
211 int (*smbus_xfer) (struct i2c_adapter *adap, u16 addr,
212 unsigned short flags, char read_write,
213 u8 command, int size, union i2c_smbus_data * data);
214
215 /* --- these optional/future use for some adapter types.*/
216 int (*slave_send)(struct i2c_adapter *,char*,int);
217 int (*slave_recv)(struct i2c_adapter *,char*,int);
218
219 /* --- ioctl like call to set div. parameters. */
220 int (*algo_control)(struct i2c_adapter *, unsigned int, unsigned long);
221
222 /* To determine what the adapter supports */
223 u32 (*functionality) (struct i2c_adapter *);
224 };
225
226 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,1,29)
227 struct proc_dir_entry;
228 #endif
229
230 /*
231 * i2c_adapter is the structure used to identify a physical i2c bus along
232 * with the access algorithms necessary to access it.
233 */
234 struct i2c_adapter {
235 char name[32]; /* some useful name to identify the adapter */
236 unsigned int id;/* == is algo->id | hwdep.struct->id, */
237 /* for registered values see below */
238 struct i2c_algorithm *algo;/* the algorithm to access the bus */
239 void *algo_data;
240
241 /* --- These may be NULL, but should increase the module use count */
242 void (*inc_use)(struct i2c_adapter *);
243 void (*dec_use)(struct i2c_adapter *);
244
245 /* --- administration stuff. */
246 int (*client_register)(struct i2c_client *);
247 int (*client_unregister)(struct i2c_client *);
248
249 void *data; /* private data for the adapter */
250 /* some data fields that are used by all types */
251 /* these data fields are readonly to the public */
252 /* and can be set via the i2c_ioctl call */
253
254 /* data fields that are valid for all devices */
255 struct semaphore lock;
256 unsigned int flags;/* flags specifying div. data */
257
258 struct i2c_client *clients[I2C_CLIENT_MAX];
259 int client_count;
260
261 int timeout;
262 int retries;
263
264 #ifdef CONFIG_PROC_FS
265 /* No need to set this when you initialize the adapter */
266 int inode;
267 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,1,29)
268 struct proc_dir_entry *proc_entry;
269 #endif
270 #endif /* def CONFIG_PROC_FS */
271 };
272
273 /*flags for the driver struct: */
274 #define I2C_DF_NOTIFY 0x01 /* notify on bus (de/a)ttaches */
275 #define I2C_DF_DUMMY 0x02 /* do not connect any clients */
276
277 /*flags for the client struct: */
278 #define I2C_CLIENT_ALLOW_USE 0x01 /* Client allows access */
279 #define I2C_CLIENT_ALLOW_MULTIPLE_USE 0x02 /* Allow multiple access-locks */
280 /* on an i2c_client */
281
282 /* i2c_client_address_data is the struct for holding default client
283 * addresses for a driver and for the parameters supplied on the
284 * command line
285 */
286 struct i2c_client_address_data {
287 unsigned short *normal_i2c;
288 unsigned short *normal_i2c_range;
289 unsigned short *probe;
290 unsigned short *probe_range;
291 unsigned short *ignore;
292 unsigned short *ignore_range;
293 unsigned short *force;
294 };
295
296 /* Internal numbers to terminate lists */
297 #define I2C_CLIENT_END 0xfffe
298
299 /* The numbers to use to set I2C bus address */
300 #define ANY_I2C_BUS 0xffff
301
302 /* The length of the option lists */
303 #define I2C_CLIENT_MAX_OPTS 48
304
305
306 /* ----- functions exported by i2c.o */
307
308 /* administration...
309 */
310 extern int i2c_add_adapter(struct i2c_adapter *);
311 extern int i2c_del_adapter(struct i2c_adapter *);
312
313 extern int i2c_add_driver(struct i2c_driver *);
314 extern int i2c_del_driver(struct i2c_driver *);
315
316 extern int i2c_attach_client(struct i2c_client *);
317 extern int i2c_detach_client(struct i2c_client *);
318
319 /* Only call these if you grab a resource that makes unloading the
320 client and the adapter it is on completely impossible. Like when a
321 /proc directory is entered. */
322 extern void i2c_inc_use_client(struct i2c_client *);
323 extern void i2c_dec_use_client(struct i2c_client *);
324
325 /* New function: This is to get an i2c_client-struct for controlling the
326 client either by using i2c_control-function or having the
327 client-module export functions that can be used with the i2c_client
328 -struct. */
329 extern struct i2c_client *i2c_get_client(int driver_id, int adapter_id,
330 struct i2c_client *prev);
331
332 /* Should be used with new function
333 extern struct i2c_client *i2c_get_client(int,int,struct i2c_client *);
334 to make sure that client-struct is valid and that it is okay to access
335 the i2c-client.
336 returns -EACCES if client doesn't allow use (default)
337 returns -EBUSY if client doesn't allow multiple use (default) and
338 usage_count >0 */
339 extern int i2c_use_client(struct i2c_client *);
340 extern int i2c_release_client(struct i2c_client *);
341
342 /* returns -EBUSY if address has been taken, 0 if not. Note that the only
343 other place at which this is called is within i2c_attach_client; so
344 you can cheat by simply not registering. Not recommended, of course! */
345 extern int i2c_check_addr (struct i2c_adapter *adapter, int addr);
346
347 /* Detect function. It itterates over all possible addresses itself.
348 * It will only call found_proc if some client is connected at the
349 * specific address (unless a 'force' matched);
350 */
351 typedef int i2c_client_found_addr_proc (struct i2c_adapter *adapter,
352 int addr, unsigned short flags,int kind);
353
354 extern int i2c_probe(struct i2c_adapter *adapter,
355 struct i2c_client_address_data *address_data,
356 i2c_client_found_addr_proc *found_proc);
357
358 /* An ioctl like call to set div. parameters of the adapter.
359 */
360 extern int i2c_control(struct i2c_client *,unsigned int, unsigned long);
361
362 /* This call returns a unique low identifier for each registered adapter,
363 * or -1 if the adapter was not regisitered.
364 */
365 extern int i2c_adapter_id(struct i2c_adapter *adap);
366
367
368
369 /* Return the functionality mask */
370 extern u32 i2c_get_functionality (struct i2c_adapter *adap);
371
372 /* Return 1 if adapter supports everything we need, 0 if not. */
373 extern int i2c_check_functionality (struct i2c_adapter *adap, u32 func);
374
375 #endif /* __KERNEL__ */
376
377 /*
378 * I2C Message - used for pure i2c transaction, also from /dev interface
379 */
380 struct i2c_msg {
381 __u16 addr; /* slave address */
382 unsigned short flags;
383 #define I2C_M_TEN 0x10 /* we have a ten bit chip address */
384 #define I2C_M_RD 0x01
385 #define I2C_M_NOSTART 0x4000
386 #define I2C_M_REV_DIR_ADDR 0x2000
387 short len; /* msg length */
388 char *buf; /* pointer to msg data */
389 };
390
391 /* To determine what functionality is present */
392
393 #define I2C_FUNC_I2C 0x00000001
394 #define I2C_FUNC_10BIT_ADDR 0x00000002
395 #define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_{REV_DIR_ADDR,NOSTART} */
396 #define I2C_FUNC_SMBUS_QUICK 0x00010000
397 #define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
398 #define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
399 #define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
400 #define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
401 #define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
402 #define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
403 #define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
404 #define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
405 #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
406 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* New I2C-like block */
407 #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* transfer */
408
409 #define I2C_FUNC_SMBUS_BYTE I2C_FUNC_SMBUS_READ_BYTE | \
410 I2C_FUNC_SMBUS_WRITE_BYTE
411 #define I2C_FUNC_SMBUS_BYTE_DATA I2C_FUNC_SMBUS_READ_BYTE_DATA | \
412 I2C_FUNC_SMBUS_WRITE_BYTE_DATA
413 #define I2C_FUNC_SMBUS_WORD_DATA I2C_FUNC_SMBUS_READ_WORD_DATA | \
414 I2C_FUNC_SMBUS_WRITE_WORD_DATA
415 #define I2C_FUNC_SMBUS_BLOCK_DATA I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
416 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
417 #define I2C_FUNC_SMBUS_I2C_BLOCK I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
418 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK
419
420 #define I2C_FUNC_SMBUS_EMUL I2C_FUNC_SMBUS_QUICK | \
421 I2C_FUNC_SMBUS_BYTE | \
422 I2C_FUNC_SMBUS_BYTE_DATA | \
423 I2C_FUNC_SMBUS_WORD_DATA | \
424 I2C_FUNC_SMBUS_PROC_CALL | \
425 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
426
427 /*
428 * Data for SMBus Messages
429 */
430 union i2c_smbus_data {
431 __u8 byte;
432 __u16 word;
433 __u8 block[33]; /* block[0] is used for length */
434 };
435
436 /* smbus_access read or write markers */
437 #define I2C_SMBUS_READ 1
438 #define I2C_SMBUS_WRITE 0
439
440 /* SMBus transaction types (size parameter in the above functions)
441 Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
442 #define I2C_SMBUS_QUICK 0
443 #define I2C_SMBUS_BYTE 1
444 #define I2C_SMBUS_BYTE_DATA 2
445 #define I2C_SMBUS_WORD_DATA 3
446 #define I2C_SMBUS_PROC_CALL 4
447 #define I2C_SMBUS_BLOCK_DATA 5
448 #define I2C_SMBUS_I2C_BLOCK_DATA 6
449
450
451 /* ----- commands for the ioctl like i2c_command call:
452 * note that additional calls are defined in the algorithm and hw
453 * dependent layers - these can be listed here, or see the
454 * corresponding header files.
455 */
456 /* -> bit-adapter specific ioctls */
457 #define I2C_RETRIES 0x0701 /* number times a device adress should */
458 /* be polled when not acknowledging */
459 #define I2C_TIMEOUT 0x0702 /* set timeout - call with int */
460
461
462 /* this is for i2c-dev.c */
463 #define I2C_SLAVE 0x0703 /* Change slave address */
464 /* Attn.: Slave address is 7 or 10 bits */
465 #define I2C_SLAVE_FORCE 0x0706 /* Change slave address */
466 /* Attn.: Slave address is 7 or 10 bits */
467 /* This changes the address, even if it */
468 /* is already taken! */
469 #define I2C_TENBIT 0x0704 /* 0 for 7 bit addrs, != 0 for 10 bit */
470
471 #define I2C_FUNCS 0x0705 /* Get the adapter functionality */
472 #define I2C_RDWR 0x0707 /* Combined R/W transfer (one stop only)*/
473 #if 0
474 #define I2C_ACK_TEST 0x0710 /* See if a slave is at a specific adress */
475 #endif
476
477 #define I2C_SMBUS 0x0720 /* SMBus-level access */
478
479 /* ... algo-bit.c recognizes */
480 #define I2C_UDELAY 0x0705 /* set delay in microsecs between each */
481 /* written byte (except address) */
482 #define I2C_MDELAY 0x0706 /* millisec delay between written bytes */
483
484 /* ----- I2C-DEV: char device interface stuff ------------------------- */
485
486 #define I2C_MAJOR 89 /* Device major number */
487
488 #ifdef __KERNEL__
489
490 # ifndef NULL
491 # define NULL ( (void *) 0 )
492 # endif
493
494 # ifndef ENODEV
495 # include <asm/errno.h>
496 # endif
497
498 /* These defines are used for probing i2c client addresses */
499 /* Default fill of many variables */
500 #define I2C_CLIENT_DEFAULTS {I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
501 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
502 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
503 I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
504 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
517 /* This is ugly. We need to evaluate I2C_CLIENT_MAX_OPTS before it is
518 stringified */
519 #define I2C_CLIENT_MODPARM_AUX1(x) "1-" #x "h"
520 #define I2C_CLIENT_MODPARM_AUX(x) I2C_CLIENT_MODPARM_AUX1(x)
521 #define I2C_CLIENT_MODPARM I2C_CLIENT_MODPARM_AUX(I2C_CLIENT_MAX_OPTS)
522
523 /* I2C_CLIENT_MODULE_PARM creates a module parameter, and puts it in the
524 module header */
525
526 #define I2C_CLIENT_MODULE_PARM(var,desc) \
527 static unsigned short var[I2C_CLIENT_MAX_OPTS] = I2C_CLIENT_DEFAULTS; \
528 MODULE_PARM(var,I2C_CLIENT_MODPARM); \
529 MODULE_PARM_DESC(var,desc)
530
531 /* This is the one you want to use in your own modules */
532 #define I2C_CLIENT_INSMOD \
533 I2C_CLIENT_MODULE_PARM(probe, \
534 "List of adapter,address pairs to scan additionally"); \
535 I2C_CLIENT_MODULE_PARM(probe_range, \
536 "List of adapter,start-addr,end-addr triples to scan " \
537 "additionally"); \
538 I2C_CLIENT_MODULE_PARM(ignore, \
539 "List of adapter,address pairs not to scan"); \
540 I2C_CLIENT_MODULE_PARM(ignore_range, \
541 "List of adapter,start-addr,end-addr triples not to " \
542 "scan"); \
543 I2C_CLIENT_MODULE_PARM(force, \
544 "List of adapter,address pairs to boldly assume " \
545 "to be present"); \
546 static struct i2c_client_address_data addr_data = \
547 {normal_i2c, normal_i2c_range, \
548 probe, probe_range, \
549 ignore, ignore_range, \
550 force}
551
552 #endif /* def __KERNEL__ */
553 #endif /* I2C_H */
554
This page was automatically generated by the
LXR engine.
Visit the LXR main site for more
information.