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-rw-r--r--Documentation/i2c/porting-clients18
-rw-r--r--Documentation/i2c/writing-clients292
2 files changed, 39 insertions, 271 deletions
diff --git a/Documentation/i2c/porting-clients b/Documentation/i2c/porting-clients
index ca272b263a92..7bf82c08f6ca 100644
--- a/Documentation/i2c/porting-clients
+++ b/Documentation/i2c/porting-clients
@@ -1,4 +1,4 @@
1Revision 6, 2005-11-20 1Revision 7, 2007-04-19
2Jean Delvare <khali@linux-fr.org> 2Jean Delvare <khali@linux-fr.org>
3Greg KH <greg@kroah.com> 3Greg KH <greg@kroah.com>
4 4
@@ -20,6 +20,10 @@ yours for best results.
20 20
21Technical changes: 21Technical changes:
22 22
23* [Driver type] Any driver that was relying on i2c-isa has to be
24 converted to a proper isa, platform or pci driver. This is not
25 covered by this guide.
26
23* [Includes] Get rid of "version.h" and <linux/i2c-proc.h>. 27* [Includes] Get rid of "version.h" and <linux/i2c-proc.h>.
24 Includes typically look like that: 28 Includes typically look like that:
25 #include <linux/module.h> 29 #include <linux/module.h>
@@ -27,12 +31,10 @@ Technical changes:
27 #include <linux/slab.h> 31 #include <linux/slab.h>
28 #include <linux/jiffies.h> 32 #include <linux/jiffies.h>
29 #include <linux/i2c.h> 33 #include <linux/i2c.h>
30 #include <linux/i2c-isa.h> /* for ISA drivers */
31 #include <linux/hwmon.h> /* for hardware monitoring drivers */ 34 #include <linux/hwmon.h> /* for hardware monitoring drivers */
32 #include <linux/hwmon-sysfs.h> 35 #include <linux/hwmon-sysfs.h>
33 #include <linux/hwmon-vid.h> /* if you need VRM support */ 36 #include <linux/hwmon-vid.h> /* if you need VRM support */
34 #include <linux/err.h> /* for class registration */ 37 #include <linux/err.h> /* for class registration */
35 #include <asm/io.h> /* if you have I/O operations */
36 Please respect this inclusion order. Some extra headers may be 38 Please respect this inclusion order. Some extra headers may be
37 required for a given driver (e.g. "lm75.h"). 39 required for a given driver (e.g. "lm75.h").
38 40
@@ -69,20 +71,16 @@ Technical changes:
69 sensors mailing list <lm-sensors@lm-sensors.org> by providing a 71 sensors mailing list <lm-sensors@lm-sensors.org> by providing a
70 patch to the Documentation/hwmon/sysfs-interface file. 72 patch to the Documentation/hwmon/sysfs-interface file.
71 73
72* [Attach] For I2C drivers, the attach function should make sure 74* [Attach] The attach function should make sure that the adapter's
73 that the adapter's class has I2C_CLASS_HWMON (or whatever class is 75 class has I2C_CLASS_HWMON (or whatever class is suitable for your
74 suitable for your driver), using the following construct: 76 driver), using the following construct:
75 if (!(adapter->class & I2C_CLASS_HWMON)) 77 if (!(adapter->class & I2C_CLASS_HWMON))
76 return 0; 78 return 0;
77 ISA-only drivers of course don't need this.
78 Call i2c_probe() instead of i2c_detect(). 79 Call i2c_probe() instead of i2c_detect().
79 80
80* [Detect] As mentioned earlier, the flags parameter is gone. 81* [Detect] As mentioned earlier, the flags parameter is gone.
81 The type_name and client_name strings are replaced by a single 82 The type_name and client_name strings are replaced by a single
82 name string, which will be filled with a lowercase, short string. 83 name string, which will be filled with a lowercase, short string.
83 In i2c-only drivers, drop the i2c_is_isa_adapter check, it's
84 useless. Same for isa-only drivers, as the test would always be
85 true. Only hybrid drivers (which are quite rare) still need it.
86 The labels used for error paths are reduced to the number needed. 84 The labels used for error paths are reduced to the number needed.
87 It is advised that the labels are given descriptive names such as 85 It is advised that the labels are given descriptive names such as
88 exit and exit_free. Don't forget to properly set err before 86 exit and exit_free. Don't forget to properly set err before
diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients
index f7e04ec849b1..3d8d36b0ad12 100644
--- a/Documentation/i2c/writing-clients
+++ b/Documentation/i2c/writing-clients
@@ -74,16 +74,13 @@ An example structure is below.
74 74
75 struct foo_data { 75 struct foo_data {
76 struct i2c_client client; 76 struct i2c_client client;
77 struct semaphore lock; /* For ISA access in `sensors' drivers. */
78 int sysctl_id; /* To keep the /proc directory entry for
79 `sensors' drivers. */
80 enum chips type; /* To keep the chips type for `sensors' drivers. */ 77 enum chips type; /* To keep the chips type for `sensors' drivers. */
81 78
82 /* Because the i2c bus is slow, it is often useful to cache the read 79 /* Because the i2c bus is slow, it is often useful to cache the read
83 information of a chip for some time (for example, 1 or 2 seconds). 80 information of a chip for some time (for example, 1 or 2 seconds).
84 It depends of course on the device whether this is really worthwhile 81 It depends of course on the device whether this is really worthwhile
85 or even sensible. */ 82 or even sensible. */
86 struct semaphore update_lock; /* When we are reading lots of information, 83 struct mutex update_lock; /* When we are reading lots of information,
87 another process should not update the 84 another process should not update the
88 below information */ 85 below information */
89 char valid; /* != 0 if the following fields are valid. */ 86 char valid; /* != 0 if the following fields are valid. */
@@ -104,8 +101,7 @@ some obscure clients). But we need generic reading and writing routines.
104I have found it useful to define foo_read and foo_write function for this. 101I have found it useful to define foo_read and foo_write function for this.
105For some cases, it will be easier to call the i2c functions directly, 102For some cases, it will be easier to call the i2c functions directly,
106but many chips have some kind of register-value idea that can easily 103but many chips have some kind of register-value idea that can easily
107be encapsulated. Also, some chips have both ISA and I2C interfaces, and 104be encapsulated.
108it useful to abstract from this (only for `sensors' drivers).
109 105
110The below functions are simple examples, and should not be copied 106The below functions are simple examples, and should not be copied
111literally. 107literally.
@@ -128,24 +124,6 @@ literally.
128 return i2c_smbus_write_word_data(client,reg,value); 124 return i2c_smbus_write_word_data(client,reg,value);
129 } 125 }
130 126
131For sensors code, you may have to cope with ISA registers too. Something
132like the below often works. Note the locking!
133
134 int foo_read_value(struct i2c_client *client, u8 reg)
135 {
136 int res;
137 if (i2c_is_isa_client(client)) {
138 down(&(((struct foo_data *) (client->data)) -> lock));
139 outb_p(reg,client->addr + FOO_ADDR_REG_OFFSET);
140 res = inb_p(client->addr + FOO_DATA_REG_OFFSET);
141 up(&(((struct foo_data *) (client->data)) -> lock));
142 return res;
143 } else
144 return i2c_smbus_read_byte_data(client,reg);
145 }
146
147Writing is done the same way.
148
149 127
150Probing and attaching 128Probing and attaching
151===================== 129=====================
@@ -257,10 +235,6 @@ detection algorithm.
257You do not have to use this parameter interface; but don't try to use 235You do not have to use this parameter interface; but don't try to use
258function i2c_probe() if you don't. 236function i2c_probe() if you don't.
259 237
260NOTE: If you want to write a `sensors' driver, the interface is slightly
261 different! See below.
262
263
264 238
265Probing classes (Legacy model) 239Probing classes (Legacy model)
266------------------------------ 240------------------------------
@@ -344,10 +318,6 @@ The detect client function is called by i2c_probe. The `kind' parameter
344contains -1 for a probed detection, 0 for a forced detection, or a positive 318contains -1 for a probed detection, 0 for a forced detection, or a positive
345number for a forced detection with a chip type forced. 319number for a forced detection with a chip type forced.
346 320
347Below, some things are only needed if this is a `sensors' driver. Those
348parts are between /* SENSORS ONLY START */ and /* SENSORS ONLY END */
349markers.
350
351Returning an error different from -ENODEV in a detect function will cause 321Returning an error different from -ENODEV in a detect function will cause
352the detection to stop: other addresses and adapters won't be scanned. 322the detection to stop: other addresses and adapters won't be scanned.
353This should only be done on fatal or internal errors, such as a memory 323This should only be done on fatal or internal errors, such as a memory
@@ -356,64 +326,20 @@ shortage or i2c_attach_client failing.
356For now, you can ignore the `flags' parameter. It is there for future use. 326For now, you can ignore the `flags' parameter. It is there for future use.
357 327
358 int foo_detect_client(struct i2c_adapter *adapter, int address, 328 int foo_detect_client(struct i2c_adapter *adapter, int address,
359 unsigned short flags, int kind) 329 int kind)
360 { 330 {
361 int err = 0; 331 int err = 0;
362 int i; 332 int i;
363 struct i2c_client *new_client; 333 struct i2c_client *client;
364 struct foo_data *data; 334 struct foo_data *data;
365 const char *client_name = ""; /* For non-`sensors' drivers, put the real 335 const char *name = "";
366 name here! */
367 336
368 /* Let's see whether this adapter can support what we need. 337 /* Let's see whether this adapter can support what we need.
369 Please substitute the things you need here! 338 Please substitute the things you need here! */
370 For `sensors' drivers, add `! is_isa &&' to the if statement */
371 if (!i2c_check_functionality(adapter,I2C_FUNC_SMBUS_WORD_DATA | 339 if (!i2c_check_functionality(adapter,I2C_FUNC_SMBUS_WORD_DATA |
372 I2C_FUNC_SMBUS_WRITE_BYTE)) 340 I2C_FUNC_SMBUS_WRITE_BYTE))
373 goto ERROR0; 341 goto ERROR0;
374 342
375 /* SENSORS ONLY START */
376 const char *type_name = "";
377 int is_isa = i2c_is_isa_adapter(adapter);
378
379 /* Do this only if the chip can additionally be found on the ISA bus
380 (hybrid chip). */
381
382 if (is_isa) {
383
384 /* Discard immediately if this ISA range is already used */
385 /* FIXME: never use check_region(), only request_region() */
386 if (check_region(address,FOO_EXTENT))
387 goto ERROR0;
388
389 /* Probe whether there is anything on this address.
390 Some example code is below, but you will have to adapt this
391 for your own driver */
392
393 if (kind < 0) /* Only if no force parameter was used */ {
394 /* We may need long timeouts at least for some chips. */
395 #define REALLY_SLOW_IO
396 i = inb_p(address + 1);
397 if (inb_p(address + 2) != i)
398 goto ERROR0;
399 if (inb_p(address + 3) != i)
400 goto ERROR0;
401 if (inb_p(address + 7) != i)
402 goto ERROR0;
403 #undef REALLY_SLOW_IO
404
405 /* Let's just hope nothing breaks here */
406 i = inb_p(address + 5) & 0x7f;
407 outb_p(~i & 0x7f,address+5);
408 if ((inb_p(address + 5) & 0x7f) != (~i & 0x7f)) {
409 outb_p(i,address+5);
410 return 0;
411 }
412 }
413 }
414
415 /* SENSORS ONLY END */
416
417 /* OK. For now, we presume we have a valid client. We now create the 343 /* OK. For now, we presume we have a valid client. We now create the
418 client structure, even though we cannot fill it completely yet. 344 client structure, even though we cannot fill it completely yet.
419 But it allows us to access several i2c functions safely */ 345 But it allows us to access several i2c functions safely */
@@ -423,13 +349,12 @@ For now, you can ignore the `flags' parameter. It is there for future use.
423 goto ERROR0; 349 goto ERROR0;
424 } 350 }
425 351
426 new_client = &data->client; 352 client = &data->client;
427 i2c_set_clientdata(new_client, data); 353 i2c_set_clientdata(client, data);
428 354
429 new_client->addr = address; 355 client->addr = address;
430 new_client->adapter = adapter; 356 client->adapter = adapter;
431 new_client->driver = &foo_driver; 357 client->driver = &foo_driver;
432 new_client->flags = 0;
433 358
434 /* Now, we do the remaining detection. If no `force' parameter is used. */ 359 /* Now, we do the remaining detection. If no `force' parameter is used. */
435 360
@@ -437,19 +362,17 @@ For now, you can ignore the `flags' parameter. It is there for future use.
437 parameter was used. */ 362 parameter was used. */
438 if (kind < 0) { 363 if (kind < 0) {
439 /* The below is of course bogus */ 364 /* The below is of course bogus */
440 if (foo_read(new_client,FOO_REG_GENERIC) != FOO_GENERIC_VALUE) 365 if (foo_read(client, FOO_REG_GENERIC) != FOO_GENERIC_VALUE)
441 goto ERROR1; 366 goto ERROR1;
442 } 367 }
443 368
444 /* SENSORS ONLY START */
445
446 /* Next, specific detection. This is especially important for `sensors' 369 /* Next, specific detection. This is especially important for `sensors'
447 devices. */ 370 devices. */
448 371
449 /* Determine the chip type. Not needed if a `force_CHIPTYPE' parameter 372 /* Determine the chip type. Not needed if a `force_CHIPTYPE' parameter
450 was used. */ 373 was used. */
451 if (kind <= 0) { 374 if (kind <= 0) {
452 i = foo_read(new_client,FOO_REG_CHIPTYPE); 375 i = foo_read(client, FOO_REG_CHIPTYPE);
453 if (i == FOO_TYPE_1) 376 if (i == FOO_TYPE_1)
454 kind = chip1; /* As defined in the enum */ 377 kind = chip1; /* As defined in the enum */
455 else if (i == FOO_TYPE_2) 378 else if (i == FOO_TYPE_2)
@@ -463,63 +386,31 @@ For now, you can ignore the `flags' parameter. It is there for future use.
463 386
464 /* Now set the type and chip names */ 387 /* Now set the type and chip names */
465 if (kind == chip1) { 388 if (kind == chip1) {
466 type_name = "chip1"; /* For /proc entry */ 389 name = "chip1";
467 client_name = "CHIP 1";
468 } else if (kind == chip2) { 390 } else if (kind == chip2) {
469 type_name = "chip2"; /* For /proc entry */ 391 name = "chip2";
470 client_name = "CHIP 2";
471 } 392 }
472 393
473 /* Reserve the ISA region */
474 if (is_isa)
475 request_region(address,FOO_EXTENT,type_name);
476
477 /* SENSORS ONLY END */
478
479 /* Fill in the remaining client fields. */ 394 /* Fill in the remaining client fields. */
480 strcpy(new_client->name,client_name); 395 strlcpy(client->name, name, I2C_NAME_SIZE);
481
482 /* SENSORS ONLY BEGIN */
483 data->type = kind; 396 data->type = kind;
484 /* SENSORS ONLY END */ 397 mutex_init(&data->update_lock); /* Only if you use this field */
485
486 data->valid = 0; /* Only if you use this field */
487 init_MUTEX(&data->update_lock); /* Only if you use this field */
488 398
489 /* Any other initializations in data must be done here too. */ 399 /* Any other initializations in data must be done here too. */
490 400
491 /* Tell the i2c layer a new client has arrived */
492 if ((err = i2c_attach_client(new_client)))
493 goto ERROR3;
494
495 /* SENSORS ONLY BEGIN */
496 /* Register a new directory entry with module sensors. See below for
497 the `template' structure. */
498 if ((i = i2c_register_entry(new_client, type_name,
499 foo_dir_table_template,THIS_MODULE)) < 0) {
500 err = i;
501 goto ERROR4;
502 }
503 data->sysctl_id = i;
504
505 /* SENSORS ONLY END */
506
507 /* This function can write default values to the client registers, if 401 /* This function can write default values to the client registers, if
508 needed. */ 402 needed. */
509 foo_init_client(new_client); 403 foo_init_client(client);
404
405 /* Tell the i2c layer a new client has arrived */
406 if ((err = i2c_attach_client(client)))
407 goto ERROR1;
408
510 return 0; 409 return 0;
511 410
512 /* OK, this is not exactly good programming practice, usually. But it is 411 /* OK, this is not exactly good programming practice, usually. But it is
513 very code-efficient in this case. */ 412 very code-efficient in this case. */
514 413
515 ERROR4:
516 i2c_detach_client(new_client);
517 ERROR3:
518 ERROR2:
519 /* SENSORS ONLY START */
520 if (is_isa)
521 release_region(address,FOO_EXTENT);
522 /* SENSORS ONLY END */
523 ERROR1: 414 ERROR1:
524 kfree(data); 415 kfree(data);
525 ERROR0: 416 ERROR0:
@@ -536,22 +427,12 @@ much simpler than the attachment code, fortunately!
536 427
537 int foo_detach_client(struct i2c_client *client) 428 int foo_detach_client(struct i2c_client *client)
538 { 429 {
539 int err,i; 430 int err;
540
541 /* SENSORS ONLY START */
542 /* Deregister with the `i2c-proc' module. */
543 i2c_deregister_entry(((struct lm78_data *)(client->data))->sysctl_id);
544 /* SENSORS ONLY END */
545 431
546 /* Try to detach the client from i2c space */ 432 /* Try to detach the client from i2c space */
547 if ((err = i2c_detach_client(client))) 433 if ((err = i2c_detach_client(client)))
548 return err; 434 return err;
549 435
550 /* HYBRID SENSORS CHIP ONLY START */
551 if i2c_is_isa_client(client)
552 release_region(client->addr,LM78_EXTENT);
553 /* HYBRID SENSORS CHIP ONLY END */
554
555 kfree(i2c_get_clientdata(client)); 436 kfree(i2c_get_clientdata(client));
556 return 0; 437 return 0;
557 } 438 }
@@ -564,42 +445,34 @@ When the kernel is booted, or when your foo driver module is inserted,
564you have to do some initializing. Fortunately, just attaching (registering) 445you have to do some initializing. Fortunately, just attaching (registering)
565the driver module is usually enough. 446the driver module is usually enough.
566 447
567 /* Keep track of how far we got in the initialization process. If several
568 things have to initialized, and we fail halfway, only those things
569 have to be cleaned up! */
570 static int __initdata foo_initialized = 0;
571
572 static int __init foo_init(void) 448 static int __init foo_init(void)
573 { 449 {
574 int res; 450 int res;
575 printk("foo version %s (%s)\n",FOO_VERSION,FOO_DATE);
576 451
577 if ((res = i2c_add_driver(&foo_driver))) { 452 if ((res = i2c_add_driver(&foo_driver))) {
578 printk("foo: Driver registration failed, module not inserted.\n"); 453 printk("foo: Driver registration failed, module not inserted.\n");
579 foo_cleanup();
580 return res; 454 return res;
581 } 455 }
582 foo_initialized ++;
583 return 0; 456 return 0;
584 } 457 }
585 458
586 void foo_cleanup(void) 459 static void __exit foo_cleanup(void)
587 { 460 {
588 if (foo_initialized == 1) { 461 i2c_del_driver(&foo_driver);
589 i2c_del_driver(&foo_driver);
590 foo_initialized --;
591 }
592 } 462 }
593 463
594 /* Substitute your own name and email address */ 464 /* Substitute your own name and email address */
595 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>" 465 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>"
596 MODULE_DESCRIPTION("Driver for Barf Inc. Foo I2C devices"); 466 MODULE_DESCRIPTION("Driver for Barf Inc. Foo I2C devices");
597 467
468 /* a few non-GPL license types are also allowed */
469 MODULE_LICENSE("GPL");
470
598 module_init(foo_init); 471 module_init(foo_init);
599 module_exit(foo_cleanup); 472 module_exit(foo_cleanup);
600 473
601Note that some functions are marked by `__init', and some data structures 474Note that some functions are marked by `__init', and some data structures
602by `__init_data'. Hose functions and structures can be removed after 475by `__initdata'. These functions and structures can be removed after
603kernel booting (or module loading) is completed. 476kernel booting (or module loading) is completed.
604 477
605 478
@@ -729,110 +602,7 @@ General purpose routines
729Below all general purpose routines are listed, that were not mentioned 602Below all general purpose routines are listed, that were not mentioned
730before. 603before.
731 604
732 /* This call returns a unique low identifier for each registered adapter, 605 /* This call returns a unique low identifier for each registered adapter.
733 * or -1 if the adapter was not registered.
734 */ 606 */
735 extern int i2c_adapter_id(struct i2c_adapter *adap); 607 extern int i2c_adapter_id(struct i2c_adapter *adap);
736 608
737
738The sensors sysctl/proc interface
739=================================
740
741This section only applies if you write `sensors' drivers.
742
743Each sensors driver creates a directory in /proc/sys/dev/sensors for each
744registered client. The directory is called something like foo-i2c-4-65.
745The sensors module helps you to do this as easily as possible.
746
747The template
748------------
749
750You will need to define a ctl_table template. This template will automatically
751be copied to a newly allocated structure and filled in where necessary when
752you call sensors_register_entry.
753
754First, I will give an example definition.
755 static ctl_table foo_dir_table_template[] = {
756 { FOO_SYSCTL_FUNC1, "func1", NULL, 0, 0644, NULL, &i2c_proc_real,
757 &i2c_sysctl_real,NULL,&foo_func },
758 { FOO_SYSCTL_FUNC2, "func2", NULL, 0, 0644, NULL, &i2c_proc_real,
759 &i2c_sysctl_real,NULL,&foo_func },
760 { FOO_SYSCTL_DATA, "data", NULL, 0, 0644, NULL, &i2c_proc_real,
761 &i2c_sysctl_real,NULL,&foo_data },
762 { 0 }
763 };
764
765In the above example, three entries are defined. They can either be
766accessed through the /proc interface, in the /proc/sys/dev/sensors/*
767directories, as files named func1, func2 and data, or alternatively
768through the sysctl interface, in the appropriate table, with identifiers
769FOO_SYSCTL_FUNC1, FOO_SYSCTL_FUNC2 and FOO_SYSCTL_DATA.
770
771The third, sixth and ninth parameters should always be NULL, and the
772fourth should always be 0. The fifth is the mode of the /proc file;
7730644 is safe, as the file will be owned by root:root.
774
775The seventh and eighth parameters should be &i2c_proc_real and
776&i2c_sysctl_real if you want to export lists of reals (scaled
777integers). You can also use your own function for them, as usual.
778Finally, the last parameter is the call-back to gather the data
779(see below) if you use the *_proc_real functions.
780
781
782Gathering the data
783------------------
784
785The call back functions (foo_func and foo_data in the above example)
786can be called in several ways; the operation parameter determines
787what should be done:
788
789 * If operation == SENSORS_PROC_REAL_INFO, you must return the
790 magnitude (scaling) in nrels_mag;
791 * If operation == SENSORS_PROC_REAL_READ, you must read information
792 from the chip and return it in results. The number of integers
793 to display should be put in nrels_mag;
794 * If operation == SENSORS_PROC_REAL_WRITE, you must write the
795 supplied information to the chip. nrels_mag will contain the number
796 of integers, results the integers themselves.
797
798The *_proc_real functions will display the elements as reals for the
799/proc interface. If you set the magnitude to 2, and supply 345 for
800SENSORS_PROC_REAL_READ, it would display 3.45; and if the user would
801write 45.6 to the /proc file, it would be returned as 4560 for
802SENSORS_PROC_REAL_WRITE. A magnitude may even be negative!
803
804An example function:
805
806 /* FOO_FROM_REG and FOO_TO_REG translate between scaled values and
807 register values. Note the use of the read cache. */
808 void foo_in(struct i2c_client *client, int operation, int ctl_name,
809 int *nrels_mag, long *results)
810 {
811 struct foo_data *data = client->data;
812 int nr = ctl_name - FOO_SYSCTL_FUNC1; /* reduce to 0 upwards */
813
814 if (operation == SENSORS_PROC_REAL_INFO)
815 *nrels_mag = 2;
816 else if (operation == SENSORS_PROC_REAL_READ) {
817 /* Update the readings cache (if necessary) */
818 foo_update_client(client);
819 /* Get the readings from the cache */
820 results[0] = FOO_FROM_REG(data->foo_func_base[nr]);
821 results[1] = FOO_FROM_REG(data->foo_func_more[nr]);
822 results[2] = FOO_FROM_REG(data->foo_func_readonly[nr]);
823 *nrels_mag = 2;
824 } else if (operation == SENSORS_PROC_REAL_WRITE) {
825 if (*nrels_mag >= 1) {
826 /* Update the cache */
827 data->foo_base[nr] = FOO_TO_REG(results[0]);
828 /* Update the chip */
829 foo_write_value(client,FOO_REG_FUNC_BASE(nr),data->foo_base[nr]);
830 }
831 if (*nrels_mag >= 2) {
832 /* Update the cache */
833 data->foo_more[nr] = FOO_TO_REG(results[1]);
834 /* Update the chip */
835 foo_write_value(client,FOO_REG_FUNC_MORE(nr),data->foo_more[nr]);
836 }
837 }
838 }