GNU Linux-libre 5.4.241-gnu1
[releases.git] / drivers / hwmon / applesmc.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * drivers/hwmon/applesmc.c - driver for Apple's SMC (accelerometer, temperature
4  * sensors, fan control, keyboard backlight control) used in Intel-based Apple
5  * computers.
6  *
7  * Copyright (C) 2007 Nicolas Boichat <nicolas@boichat.ch>
8  * Copyright (C) 2010 Henrik Rydberg <rydberg@euromail.se>
9  *
10  * Based on hdaps.c driver:
11  * Copyright (C) 2005 Robert Love <rml@novell.com>
12  * Copyright (C) 2005 Jesper Juhl <jj@chaosbits.net>
13  *
14  * Fan control based on smcFanControl:
15  * Copyright (C) 2006 Hendrik Holtmann <holtmann@mac.com>
16  */
17
18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19
20 #include <linux/delay.h>
21 #include <linux/platform_device.h>
22 #include <linux/input-polldev.h>
23 #include <linux/kernel.h>
24 #include <linux/slab.h>
25 #include <linux/module.h>
26 #include <linux/timer.h>
27 #include <linux/dmi.h>
28 #include <linux/mutex.h>
29 #include <linux/hwmon-sysfs.h>
30 #include <linux/io.h>
31 #include <linux/leds.h>
32 #include <linux/hwmon.h>
33 #include <linux/workqueue.h>
34 #include <linux/err.h>
35
36 /* data port used by Apple SMC */
37 #define APPLESMC_DATA_PORT      0x300
38 /* command/status port used by Apple SMC */
39 #define APPLESMC_CMD_PORT       0x304
40
41 #define APPLESMC_NR_PORTS       32 /* 0x300-0x31f */
42
43 #define APPLESMC_MAX_DATA_LENGTH 32
44
45 /* wait up to 128 ms for a status change. */
46 #define APPLESMC_MIN_WAIT       0x0010
47 #define APPLESMC_RETRY_WAIT     0x0100
48 #define APPLESMC_MAX_WAIT       0x20000
49
50 #define APPLESMC_READ_CMD       0x10
51 #define APPLESMC_WRITE_CMD      0x11
52 #define APPLESMC_GET_KEY_BY_INDEX_CMD   0x12
53 #define APPLESMC_GET_KEY_TYPE_CMD       0x13
54
55 #define KEY_COUNT_KEY           "#KEY" /* r-o ui32 */
56
57 #define LIGHT_SENSOR_LEFT_KEY   "ALV0" /* r-o {alv (6-10 bytes) */
58 #define LIGHT_SENSOR_RIGHT_KEY  "ALV1" /* r-o {alv (6-10 bytes) */
59 #define BACKLIGHT_KEY           "LKSB" /* w-o {lkb (2 bytes) */
60
61 #define CLAMSHELL_KEY           "MSLD" /* r-o ui8 (unused) */
62
63 #define MOTION_SENSOR_X_KEY     "MO_X" /* r-o sp78 (2 bytes) */
64 #define MOTION_SENSOR_Y_KEY     "MO_Y" /* r-o sp78 (2 bytes) */
65 #define MOTION_SENSOR_Z_KEY     "MO_Z" /* r-o sp78 (2 bytes) */
66 #define MOTION_SENSOR_KEY       "MOCN" /* r/w ui16 */
67
68 #define FANS_COUNT              "FNum" /* r-o ui8 */
69 #define FANS_MANUAL             "FS! " /* r-w ui16 */
70 #define FAN_ID_FMT              "F%dID" /* r-o char[16] */
71
72 #define TEMP_SENSOR_TYPE        "sp78"
73
74 /* List of keys used to read/write fan speeds */
75 static const char *const fan_speed_fmt[] = {
76         "F%dAc",                /* actual speed */
77         "F%dMn",                /* minimum speed (rw) */
78         "F%dMx",                /* maximum speed */
79         "F%dSf",                /* safe speed - not all models */
80         "F%dTg",                /* target speed (manual: rw) */
81 };
82
83 #define INIT_TIMEOUT_MSECS      5000    /* wait up to 5s for device init ... */
84 #define INIT_WAIT_MSECS         50      /* ... in 50ms increments */
85
86 #define APPLESMC_POLL_INTERVAL  50      /* msecs */
87 #define APPLESMC_INPUT_FUZZ     4       /* input event threshold */
88 #define APPLESMC_INPUT_FLAT     4
89
90 #define to_index(attr) (to_sensor_dev_attr(attr)->index & 0xffff)
91 #define to_option(attr) (to_sensor_dev_attr(attr)->index >> 16)
92
93 /* Dynamic device node attributes */
94 struct applesmc_dev_attr {
95         struct sensor_device_attribute sda;     /* hwmon attributes */
96         char name[32];                          /* room for node file name */
97 };
98
99 /* Dynamic device node group */
100 struct applesmc_node_group {
101         char *format;                           /* format string */
102         void *show;                             /* show function */
103         void *store;                            /* store function */
104         int option;                             /* function argument */
105         struct applesmc_dev_attr *nodes;        /* dynamic node array */
106 };
107
108 /* AppleSMC entry - cached register information */
109 struct applesmc_entry {
110         char key[5];            /* four-letter key code */
111         u8 valid;               /* set when entry is successfully read once */
112         u8 len;                 /* bounded by APPLESMC_MAX_DATA_LENGTH */
113         char type[5];           /* four-letter type code */
114         u8 flags;               /* 0x10: func; 0x40: write; 0x80: read */
115 };
116
117 /* Register lookup and registers common to all SMCs */
118 static struct applesmc_registers {
119         struct mutex mutex;             /* register read/write mutex */
120         unsigned int key_count;         /* number of SMC registers */
121         unsigned int fan_count;         /* number of fans */
122         unsigned int temp_count;        /* number of temperature registers */
123         unsigned int temp_begin;        /* temperature lower index bound */
124         unsigned int temp_end;          /* temperature upper index bound */
125         unsigned int index_count;       /* size of temperature index array */
126         int num_light_sensors;          /* number of light sensors */
127         bool has_accelerometer;         /* has motion sensor */
128         bool has_key_backlight;         /* has keyboard backlight */
129         bool init_complete;             /* true when fully initialized */
130         struct applesmc_entry *cache;   /* cached key entries */
131         const char **index;             /* temperature key index */
132 } smcreg = {
133         .mutex = __MUTEX_INITIALIZER(smcreg.mutex),
134 };
135
136 static const int debug;
137 static struct platform_device *pdev;
138 static s16 rest_x;
139 static s16 rest_y;
140 static u8 backlight_state[2];
141
142 static struct device *hwmon_dev;
143 static struct input_polled_dev *applesmc_idev;
144
145 /*
146  * Last index written to key_at_index sysfs file, and value to use for all other
147  * key_at_index_* sysfs files.
148  */
149 static unsigned int key_at_index;
150
151 static struct workqueue_struct *applesmc_led_wq;
152
153 /*
154  * wait_read - Wait for a byte to appear on SMC port. Callers must
155  * hold applesmc_lock.
156  */
157 static int wait_read(void)
158 {
159         u8 status;
160         int us;
161         for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
162                 udelay(us);
163                 status = inb(APPLESMC_CMD_PORT);
164                 /* read: wait for smc to settle */
165                 if (status & 0x01)
166                         return 0;
167         }
168
169         pr_warn("wait_read() fail: 0x%02x\n", status);
170         return -EIO;
171 }
172
173 /*
174  * send_byte - Write to SMC port, retrying when necessary. Callers
175  * must hold applesmc_lock.
176  */
177 static int send_byte(u8 cmd, u16 port)
178 {
179         u8 status;
180         int us;
181
182         outb(cmd, port);
183         for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
184                 udelay(us);
185                 status = inb(APPLESMC_CMD_PORT);
186                 /* write: wait for smc to settle */
187                 if (status & 0x02)
188                         continue;
189                 /* ready: cmd accepted, return */
190                 if (status & 0x04)
191                         return 0;
192                 /* timeout: give up */
193                 if (us << 1 == APPLESMC_MAX_WAIT)
194                         break;
195                 /* busy: long wait and resend */
196                 udelay(APPLESMC_RETRY_WAIT);
197                 outb(cmd, port);
198         }
199
200         pr_warn("send_byte(0x%02x, 0x%04x) fail: 0x%02x\n", cmd, port, status);
201         return -EIO;
202 }
203
204 static int send_command(u8 cmd)
205 {
206         return send_byte(cmd, APPLESMC_CMD_PORT);
207 }
208
209 static int send_argument(const char *key)
210 {
211         int i;
212
213         for (i = 0; i < 4; i++)
214                 if (send_byte(key[i], APPLESMC_DATA_PORT))
215                         return -EIO;
216         return 0;
217 }
218
219 static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
220 {
221         u8 status, data = 0;
222         int i;
223
224         if (send_command(cmd) || send_argument(key)) {
225                 pr_warn("%.4s: read arg fail\n", key);
226                 return -EIO;
227         }
228
229         /* This has no effect on newer (2012) SMCs */
230         if (send_byte(len, APPLESMC_DATA_PORT)) {
231                 pr_warn("%.4s: read len fail\n", key);
232                 return -EIO;
233         }
234
235         for (i = 0; i < len; i++) {
236                 if (wait_read()) {
237                         pr_warn("%.4s: read data[%d] fail\n", key, i);
238                         return -EIO;
239                 }
240                 buffer[i] = inb(APPLESMC_DATA_PORT);
241         }
242
243         /* Read the data port until bit0 is cleared */
244         for (i = 0; i < 16; i++) {
245                 udelay(APPLESMC_MIN_WAIT);
246                 status = inb(APPLESMC_CMD_PORT);
247                 if (!(status & 0x01))
248                         break;
249                 data = inb(APPLESMC_DATA_PORT);
250         }
251         if (i)
252                 pr_warn("flushed %d bytes, last value is: %d\n", i, data);
253
254         return 0;
255 }
256
257 static int write_smc(u8 cmd, const char *key, const u8 *buffer, u8 len)
258 {
259         int i;
260
261         if (send_command(cmd) || send_argument(key)) {
262                 pr_warn("%s: write arg fail\n", key);
263                 return -EIO;
264         }
265
266         if (send_byte(len, APPLESMC_DATA_PORT)) {
267                 pr_warn("%.4s: write len fail\n", key);
268                 return -EIO;
269         }
270
271         for (i = 0; i < len; i++) {
272                 if (send_byte(buffer[i], APPLESMC_DATA_PORT)) {
273                         pr_warn("%s: write data fail\n", key);
274                         return -EIO;
275                 }
276         }
277
278         return 0;
279 }
280
281 static int read_register_count(unsigned int *count)
282 {
283         __be32 be;
284         int ret;
285
286         ret = read_smc(APPLESMC_READ_CMD, KEY_COUNT_KEY, (u8 *)&be, 4);
287         if (ret)
288                 return ret;
289
290         *count = be32_to_cpu(be);
291         return 0;
292 }
293
294 /*
295  * Serialized I/O
296  *
297  * Returns zero on success or a negative error on failure.
298  * All functions below are concurrency safe - callers should NOT hold lock.
299  */
300
301 static int applesmc_read_entry(const struct applesmc_entry *entry,
302                                u8 *buf, u8 len)
303 {
304         int ret;
305
306         if (entry->len != len)
307                 return -EINVAL;
308         mutex_lock(&smcreg.mutex);
309         ret = read_smc(APPLESMC_READ_CMD, entry->key, buf, len);
310         mutex_unlock(&smcreg.mutex);
311
312         return ret;
313 }
314
315 static int applesmc_write_entry(const struct applesmc_entry *entry,
316                                 const u8 *buf, u8 len)
317 {
318         int ret;
319
320         if (entry->len != len)
321                 return -EINVAL;
322         mutex_lock(&smcreg.mutex);
323         ret = write_smc(APPLESMC_WRITE_CMD, entry->key, buf, len);
324         mutex_unlock(&smcreg.mutex);
325         return ret;
326 }
327
328 static const struct applesmc_entry *applesmc_get_entry_by_index(int index)
329 {
330         struct applesmc_entry *cache = &smcreg.cache[index];
331         u8 key[4], info[6];
332         __be32 be;
333         int ret = 0;
334
335         if (cache->valid)
336                 return cache;
337
338         mutex_lock(&smcreg.mutex);
339
340         if (cache->valid)
341                 goto out;
342         be = cpu_to_be32(index);
343         ret = read_smc(APPLESMC_GET_KEY_BY_INDEX_CMD, (u8 *)&be, key, 4);
344         if (ret)
345                 goto out;
346         ret = read_smc(APPLESMC_GET_KEY_TYPE_CMD, key, info, 6);
347         if (ret)
348                 goto out;
349
350         memcpy(cache->key, key, 4);
351         cache->len = info[0];
352         memcpy(cache->type, &info[1], 4);
353         cache->flags = info[5];
354         cache->valid = 1;
355
356 out:
357         mutex_unlock(&smcreg.mutex);
358         if (ret)
359                 return ERR_PTR(ret);
360         return cache;
361 }
362
363 static int applesmc_get_lower_bound(unsigned int *lo, const char *key)
364 {
365         int begin = 0, end = smcreg.key_count;
366         const struct applesmc_entry *entry;
367
368         while (begin != end) {
369                 int middle = begin + (end - begin) / 2;
370                 entry = applesmc_get_entry_by_index(middle);
371                 if (IS_ERR(entry)) {
372                         *lo = 0;
373                         return PTR_ERR(entry);
374                 }
375                 if (strcmp(entry->key, key) < 0)
376                         begin = middle + 1;
377                 else
378                         end = middle;
379         }
380
381         *lo = begin;
382         return 0;
383 }
384
385 static int applesmc_get_upper_bound(unsigned int *hi, const char *key)
386 {
387         int begin = 0, end = smcreg.key_count;
388         const struct applesmc_entry *entry;
389
390         while (begin != end) {
391                 int middle = begin + (end - begin) / 2;
392                 entry = applesmc_get_entry_by_index(middle);
393                 if (IS_ERR(entry)) {
394                         *hi = smcreg.key_count;
395                         return PTR_ERR(entry);
396                 }
397                 if (strcmp(key, entry->key) < 0)
398                         end = middle;
399                 else
400                         begin = middle + 1;
401         }
402
403         *hi = begin;
404         return 0;
405 }
406
407 static const struct applesmc_entry *applesmc_get_entry_by_key(const char *key)
408 {
409         int begin, end;
410         int ret;
411
412         ret = applesmc_get_lower_bound(&begin, key);
413         if (ret)
414                 return ERR_PTR(ret);
415         ret = applesmc_get_upper_bound(&end, key);
416         if (ret)
417                 return ERR_PTR(ret);
418         if (end - begin != 1)
419                 return ERR_PTR(-EINVAL);
420
421         return applesmc_get_entry_by_index(begin);
422 }
423
424 static int applesmc_read_key(const char *key, u8 *buffer, u8 len)
425 {
426         const struct applesmc_entry *entry;
427
428         entry = applesmc_get_entry_by_key(key);
429         if (IS_ERR(entry))
430                 return PTR_ERR(entry);
431
432         return applesmc_read_entry(entry, buffer, len);
433 }
434
435 static int applesmc_write_key(const char *key, const u8 *buffer, u8 len)
436 {
437         const struct applesmc_entry *entry;
438
439         entry = applesmc_get_entry_by_key(key);
440         if (IS_ERR(entry))
441                 return PTR_ERR(entry);
442
443         return applesmc_write_entry(entry, buffer, len);
444 }
445
446 static int applesmc_has_key(const char *key, bool *value)
447 {
448         const struct applesmc_entry *entry;
449
450         entry = applesmc_get_entry_by_key(key);
451         if (IS_ERR(entry) && PTR_ERR(entry) != -EINVAL)
452                 return PTR_ERR(entry);
453
454         *value = !IS_ERR(entry);
455         return 0;
456 }
457
458 /*
459  * applesmc_read_s16 - Read 16-bit signed big endian register
460  */
461 static int applesmc_read_s16(const char *key, s16 *value)
462 {
463         u8 buffer[2];
464         int ret;
465
466         ret = applesmc_read_key(key, buffer, 2);
467         if (ret)
468                 return ret;
469
470         *value = ((s16)buffer[0] << 8) | buffer[1];
471         return 0;
472 }
473
474 /*
475  * applesmc_device_init - initialize the accelerometer.  Can sleep.
476  */
477 static void applesmc_device_init(void)
478 {
479         int total;
480         u8 buffer[2];
481
482         if (!smcreg.has_accelerometer)
483                 return;
484
485         for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
486                 if (!applesmc_read_key(MOTION_SENSOR_KEY, buffer, 2) &&
487                                 (buffer[0] != 0x00 || buffer[1] != 0x00))
488                         return;
489                 buffer[0] = 0xe0;
490                 buffer[1] = 0x00;
491                 applesmc_write_key(MOTION_SENSOR_KEY, buffer, 2);
492                 msleep(INIT_WAIT_MSECS);
493         }
494
495         pr_warn("failed to init the device\n");
496 }
497
498 static int applesmc_init_index(struct applesmc_registers *s)
499 {
500         const struct applesmc_entry *entry;
501         unsigned int i;
502
503         if (s->index)
504                 return 0;
505
506         s->index = kcalloc(s->temp_count, sizeof(s->index[0]), GFP_KERNEL);
507         if (!s->index)
508                 return -ENOMEM;
509
510         for (i = s->temp_begin; i < s->temp_end; i++) {
511                 entry = applesmc_get_entry_by_index(i);
512                 if (IS_ERR(entry))
513                         continue;
514                 if (strcmp(entry->type, TEMP_SENSOR_TYPE))
515                         continue;
516                 s->index[s->index_count++] = entry->key;
517         }
518
519         return 0;
520 }
521
522 /*
523  * applesmc_init_smcreg_try - Try to initialize register cache. Idempotent.
524  */
525 static int applesmc_init_smcreg_try(void)
526 {
527         struct applesmc_registers *s = &smcreg;
528         bool left_light_sensor = 0, right_light_sensor = 0;
529         unsigned int count;
530         u8 tmp[1];
531         int ret;
532
533         if (s->init_complete)
534                 return 0;
535
536         ret = read_register_count(&count);
537         if (ret)
538                 return ret;
539
540         if (s->cache && s->key_count != count) {
541                 pr_warn("key count changed from %d to %d\n",
542                         s->key_count, count);
543                 kfree(s->cache);
544                 s->cache = NULL;
545         }
546         s->key_count = count;
547
548         if (!s->cache)
549                 s->cache = kcalloc(s->key_count, sizeof(*s->cache), GFP_KERNEL);
550         if (!s->cache)
551                 return -ENOMEM;
552
553         ret = applesmc_read_key(FANS_COUNT, tmp, 1);
554         if (ret)
555                 return ret;
556         s->fan_count = tmp[0];
557         if (s->fan_count > 10)
558                 s->fan_count = 10;
559
560         ret = applesmc_get_lower_bound(&s->temp_begin, "T");
561         if (ret)
562                 return ret;
563         ret = applesmc_get_lower_bound(&s->temp_end, "U");
564         if (ret)
565                 return ret;
566         s->temp_count = s->temp_end - s->temp_begin;
567
568         ret = applesmc_init_index(s);
569         if (ret)
570                 return ret;
571
572         ret = applesmc_has_key(LIGHT_SENSOR_LEFT_KEY, &left_light_sensor);
573         if (ret)
574                 return ret;
575         ret = applesmc_has_key(LIGHT_SENSOR_RIGHT_KEY, &right_light_sensor);
576         if (ret)
577                 return ret;
578         ret = applesmc_has_key(MOTION_SENSOR_KEY, &s->has_accelerometer);
579         if (ret)
580                 return ret;
581         ret = applesmc_has_key(BACKLIGHT_KEY, &s->has_key_backlight);
582         if (ret)
583                 return ret;
584
585         s->num_light_sensors = left_light_sensor + right_light_sensor;
586         s->init_complete = true;
587
588         pr_info("key=%d fan=%d temp=%d index=%d acc=%d lux=%d kbd=%d\n",
589                s->key_count, s->fan_count, s->temp_count, s->index_count,
590                s->has_accelerometer,
591                s->num_light_sensors,
592                s->has_key_backlight);
593
594         return 0;
595 }
596
597 static void applesmc_destroy_smcreg(void)
598 {
599         kfree(smcreg.index);
600         smcreg.index = NULL;
601         kfree(smcreg.cache);
602         smcreg.cache = NULL;
603         smcreg.init_complete = false;
604 }
605
606 /*
607  * applesmc_init_smcreg - Initialize register cache.
608  *
609  * Retries until initialization is successful, or the operation times out.
610  *
611  */
612 static int applesmc_init_smcreg(void)
613 {
614         int ms, ret;
615
616         for (ms = 0; ms < INIT_TIMEOUT_MSECS; ms += INIT_WAIT_MSECS) {
617                 ret = applesmc_init_smcreg_try();
618                 if (!ret) {
619                         if (ms)
620                                 pr_info("init_smcreg() took %d ms\n", ms);
621                         return 0;
622                 }
623                 msleep(INIT_WAIT_MSECS);
624         }
625
626         applesmc_destroy_smcreg();
627
628         return ret;
629 }
630
631 /* Device model stuff */
632 static int applesmc_probe(struct platform_device *dev)
633 {
634         int ret;
635
636         ret = applesmc_init_smcreg();
637         if (ret)
638                 return ret;
639
640         applesmc_device_init();
641
642         return 0;
643 }
644
645 /* Synchronize device with memorized backlight state */
646 static int applesmc_pm_resume(struct device *dev)
647 {
648         if (smcreg.has_key_backlight)
649                 applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
650         return 0;
651 }
652
653 /* Reinitialize device on resume from hibernation */
654 static int applesmc_pm_restore(struct device *dev)
655 {
656         applesmc_device_init();
657         return applesmc_pm_resume(dev);
658 }
659
660 static const struct dev_pm_ops applesmc_pm_ops = {
661         .resume = applesmc_pm_resume,
662         .restore = applesmc_pm_restore,
663 };
664
665 static struct platform_driver applesmc_driver = {
666         .probe = applesmc_probe,
667         .driver = {
668                 .name = "applesmc",
669                 .pm = &applesmc_pm_ops,
670         },
671 };
672
673 /*
674  * applesmc_calibrate - Set our "resting" values.  Callers must
675  * hold applesmc_lock.
676  */
677 static void applesmc_calibrate(void)
678 {
679         applesmc_read_s16(MOTION_SENSOR_X_KEY, &rest_x);
680         applesmc_read_s16(MOTION_SENSOR_Y_KEY, &rest_y);
681         rest_x = -rest_x;
682 }
683
684 static void applesmc_idev_poll(struct input_polled_dev *dev)
685 {
686         struct input_dev *idev = dev->input;
687         s16 x, y;
688
689         if (applesmc_read_s16(MOTION_SENSOR_X_KEY, &x))
690                 return;
691         if (applesmc_read_s16(MOTION_SENSOR_Y_KEY, &y))
692                 return;
693
694         x = -x;
695         input_report_abs(idev, ABS_X, x - rest_x);
696         input_report_abs(idev, ABS_Y, y - rest_y);
697         input_sync(idev);
698 }
699
700 /* Sysfs Files */
701
702 static ssize_t applesmc_name_show(struct device *dev,
703                                    struct device_attribute *attr, char *buf)
704 {
705         return snprintf(buf, PAGE_SIZE, "applesmc\n");
706 }
707
708 static ssize_t applesmc_position_show(struct device *dev,
709                                    struct device_attribute *attr, char *buf)
710 {
711         int ret;
712         s16 x, y, z;
713
714         ret = applesmc_read_s16(MOTION_SENSOR_X_KEY, &x);
715         if (ret)
716                 goto out;
717         ret = applesmc_read_s16(MOTION_SENSOR_Y_KEY, &y);
718         if (ret)
719                 goto out;
720         ret = applesmc_read_s16(MOTION_SENSOR_Z_KEY, &z);
721         if (ret)
722                 goto out;
723
724 out:
725         if (ret)
726                 return ret;
727         else
728                 return snprintf(buf, PAGE_SIZE, "(%d,%d,%d)\n", x, y, z);
729 }
730
731 static ssize_t applesmc_light_show(struct device *dev,
732                                 struct device_attribute *attr, char *sysfsbuf)
733 {
734         const struct applesmc_entry *entry;
735         static int data_length;
736         int ret;
737         u8 left = 0, right = 0;
738         u8 buffer[10];
739
740         if (!data_length) {
741                 entry = applesmc_get_entry_by_key(LIGHT_SENSOR_LEFT_KEY);
742                 if (IS_ERR(entry))
743                         return PTR_ERR(entry);
744                 if (entry->len > 10)
745                         return -ENXIO;
746                 data_length = entry->len;
747                 pr_info("light sensor data length set to %d\n", data_length);
748         }
749
750         ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, buffer, data_length);
751         if (ret)
752                 goto out;
753         /* newer macbooks report a single 10-bit bigendian value */
754         if (data_length == 10) {
755                 left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2;
756                 goto out;
757         }
758         left = buffer[2];
759
760         ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length);
761         if (ret)
762                 goto out;
763         right = buffer[2];
764
765 out:
766         if (ret)
767                 return ret;
768         else
769                 return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", left, right);
770 }
771
772 /* Displays sensor key as label */
773 static ssize_t applesmc_show_sensor_label(struct device *dev,
774                         struct device_attribute *devattr, char *sysfsbuf)
775 {
776         const char *key = smcreg.index[to_index(devattr)];
777
778         return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", key);
779 }
780
781 /* Displays degree Celsius * 1000 */
782 static ssize_t applesmc_show_temperature(struct device *dev,
783                         struct device_attribute *devattr, char *sysfsbuf)
784 {
785         const char *key = smcreg.index[to_index(devattr)];
786         int ret;
787         s16 value;
788         int temp;
789
790         ret = applesmc_read_s16(key, &value);
791         if (ret)
792                 return ret;
793
794         temp = 250 * (value >> 6);
795
796         return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", temp);
797 }
798
799 static ssize_t applesmc_show_fan_speed(struct device *dev,
800                                 struct device_attribute *attr, char *sysfsbuf)
801 {
802         int ret;
803         unsigned int speed = 0;
804         char newkey[5];
805         u8 buffer[2];
806
807         scnprintf(newkey, sizeof(newkey), fan_speed_fmt[to_option(attr)],
808                   to_index(attr));
809
810         ret = applesmc_read_key(newkey, buffer, 2);
811         if (ret)
812                 return ret;
813
814         speed = ((buffer[0] << 8 | buffer[1]) >> 2);
815         return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
816 }
817
818 static ssize_t applesmc_store_fan_speed(struct device *dev,
819                                         struct device_attribute *attr,
820                                         const char *sysfsbuf, size_t count)
821 {
822         int ret;
823         unsigned long speed;
824         char newkey[5];
825         u8 buffer[2];
826
827         if (kstrtoul(sysfsbuf, 10, &speed) < 0 || speed >= 0x4000)
828                 return -EINVAL;         /* Bigger than a 14-bit value */
829
830         scnprintf(newkey, sizeof(newkey), fan_speed_fmt[to_option(attr)],
831                   to_index(attr));
832
833         buffer[0] = (speed >> 6) & 0xff;
834         buffer[1] = (speed << 2) & 0xff;
835         ret = applesmc_write_key(newkey, buffer, 2);
836
837         if (ret)
838                 return ret;
839         else
840                 return count;
841 }
842
843 static ssize_t applesmc_show_fan_manual(struct device *dev,
844                         struct device_attribute *attr, char *sysfsbuf)
845 {
846         int ret;
847         u16 manual = 0;
848         u8 buffer[2];
849
850         ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
851         if (ret)
852                 return ret;
853
854         manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01;
855         return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
856 }
857
858 static ssize_t applesmc_store_fan_manual(struct device *dev,
859                                          struct device_attribute *attr,
860                                          const char *sysfsbuf, size_t count)
861 {
862         int ret;
863         u8 buffer[2];
864         unsigned long input;
865         u16 val;
866
867         if (kstrtoul(sysfsbuf, 10, &input) < 0)
868                 return -EINVAL;
869
870         ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
871         if (ret)
872                 goto out;
873
874         val = (buffer[0] << 8 | buffer[1]);
875
876         if (input)
877                 val = val | (0x01 << to_index(attr));
878         else
879                 val = val & ~(0x01 << to_index(attr));
880
881         buffer[0] = (val >> 8) & 0xFF;
882         buffer[1] = val & 0xFF;
883
884         ret = applesmc_write_key(FANS_MANUAL, buffer, 2);
885
886 out:
887         if (ret)
888                 return ret;
889         else
890                 return count;
891 }
892
893 static ssize_t applesmc_show_fan_position(struct device *dev,
894                                 struct device_attribute *attr, char *sysfsbuf)
895 {
896         int ret;
897         char newkey[5];
898         u8 buffer[17];
899
900         scnprintf(newkey, sizeof(newkey), FAN_ID_FMT, to_index(attr));
901
902         ret = applesmc_read_key(newkey, buffer, 16);
903         buffer[16] = 0;
904
905         if (ret)
906                 return ret;
907         else
908                 return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", buffer+4);
909 }
910
911 static ssize_t applesmc_calibrate_show(struct device *dev,
912                                 struct device_attribute *attr, char *sysfsbuf)
913 {
914         return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", rest_x, rest_y);
915 }
916
917 static ssize_t applesmc_calibrate_store(struct device *dev,
918         struct device_attribute *attr, const char *sysfsbuf, size_t count)
919 {
920         applesmc_calibrate();
921
922         return count;
923 }
924
925 static void applesmc_backlight_set(struct work_struct *work)
926 {
927         applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
928 }
929 static DECLARE_WORK(backlight_work, &applesmc_backlight_set);
930
931 static void applesmc_brightness_set(struct led_classdev *led_cdev,
932                                                 enum led_brightness value)
933 {
934         int ret;
935
936         backlight_state[0] = value;
937         ret = queue_work(applesmc_led_wq, &backlight_work);
938
939         if (debug && (!ret))
940                 dev_dbg(led_cdev->dev, "work was already on the queue.\n");
941 }
942
943 static ssize_t applesmc_key_count_show(struct device *dev,
944                                 struct device_attribute *attr, char *sysfsbuf)
945 {
946         int ret;
947         u8 buffer[4];
948         u32 count;
949
950         ret = applesmc_read_key(KEY_COUNT_KEY, buffer, 4);
951         if (ret)
952                 return ret;
953
954         count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
955                                                 ((u32)buffer[2]<<8) + buffer[3];
956         return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
957 }
958
959 static ssize_t applesmc_key_at_index_read_show(struct device *dev,
960                                 struct device_attribute *attr, char *sysfsbuf)
961 {
962         const struct applesmc_entry *entry;
963         int ret;
964
965         entry = applesmc_get_entry_by_index(key_at_index);
966         if (IS_ERR(entry))
967                 return PTR_ERR(entry);
968         ret = applesmc_read_entry(entry, sysfsbuf, entry->len);
969         if (ret)
970                 return ret;
971
972         return entry->len;
973 }
974
975 static ssize_t applesmc_key_at_index_data_length_show(struct device *dev,
976                                 struct device_attribute *attr, char *sysfsbuf)
977 {
978         const struct applesmc_entry *entry;
979
980         entry = applesmc_get_entry_by_index(key_at_index);
981         if (IS_ERR(entry))
982                 return PTR_ERR(entry);
983
984         return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", entry->len);
985 }
986
987 static ssize_t applesmc_key_at_index_type_show(struct device *dev,
988                                 struct device_attribute *attr, char *sysfsbuf)
989 {
990         const struct applesmc_entry *entry;
991
992         entry = applesmc_get_entry_by_index(key_at_index);
993         if (IS_ERR(entry))
994                 return PTR_ERR(entry);
995
996         return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->type);
997 }
998
999 static ssize_t applesmc_key_at_index_name_show(struct device *dev,
1000                                 struct device_attribute *attr, char *sysfsbuf)
1001 {
1002         const struct applesmc_entry *entry;
1003
1004         entry = applesmc_get_entry_by_index(key_at_index);
1005         if (IS_ERR(entry))
1006                 return PTR_ERR(entry);
1007
1008         return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
1009 }
1010
1011 static ssize_t applesmc_key_at_index_show(struct device *dev,
1012                                 struct device_attribute *attr, char *sysfsbuf)
1013 {
1014         return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", key_at_index);
1015 }
1016
1017 static ssize_t applesmc_key_at_index_store(struct device *dev,
1018         struct device_attribute *attr, const char *sysfsbuf, size_t count)
1019 {
1020         unsigned long newkey;
1021
1022         if (kstrtoul(sysfsbuf, 10, &newkey) < 0
1023             || newkey >= smcreg.key_count)
1024                 return -EINVAL;
1025
1026         key_at_index = newkey;
1027         return count;
1028 }
1029
1030 static struct led_classdev applesmc_backlight = {
1031         .name                   = "smc::kbd_backlight",
1032         .default_trigger        = "nand-disk",
1033         .brightness_set         = applesmc_brightness_set,
1034 };
1035
1036 static struct applesmc_node_group info_group[] = {
1037         { "name", applesmc_name_show },
1038         { "key_count", applesmc_key_count_show },
1039         { "key_at_index", applesmc_key_at_index_show, applesmc_key_at_index_store },
1040         { "key_at_index_name", applesmc_key_at_index_name_show },
1041         { "key_at_index_type", applesmc_key_at_index_type_show },
1042         { "key_at_index_data_length", applesmc_key_at_index_data_length_show },
1043         { "key_at_index_data", applesmc_key_at_index_read_show },
1044         { }
1045 };
1046
1047 static struct applesmc_node_group accelerometer_group[] = {
1048         { "position", applesmc_position_show },
1049         { "calibrate", applesmc_calibrate_show, applesmc_calibrate_store },
1050         { }
1051 };
1052
1053 static struct applesmc_node_group light_sensor_group[] = {
1054         { "light", applesmc_light_show },
1055         { }
1056 };
1057
1058 static struct applesmc_node_group fan_group[] = {
1059         { "fan%d_label", applesmc_show_fan_position },
1060         { "fan%d_input", applesmc_show_fan_speed, NULL, 0 },
1061         { "fan%d_min", applesmc_show_fan_speed, applesmc_store_fan_speed, 1 },
1062         { "fan%d_max", applesmc_show_fan_speed, NULL, 2 },
1063         { "fan%d_safe", applesmc_show_fan_speed, NULL, 3 },
1064         { "fan%d_output", applesmc_show_fan_speed, applesmc_store_fan_speed, 4 },
1065         { "fan%d_manual", applesmc_show_fan_manual, applesmc_store_fan_manual },
1066         { }
1067 };
1068
1069 static struct applesmc_node_group temp_group[] = {
1070         { "temp%d_label", applesmc_show_sensor_label },
1071         { "temp%d_input", applesmc_show_temperature },
1072         { }
1073 };
1074
1075 /* Module stuff */
1076
1077 /*
1078  * applesmc_destroy_nodes - remove files and free associated memory
1079  */
1080 static void applesmc_destroy_nodes(struct applesmc_node_group *groups)
1081 {
1082         struct applesmc_node_group *grp;
1083         struct applesmc_dev_attr *node;
1084
1085         for (grp = groups; grp->nodes; grp++) {
1086                 for (node = grp->nodes; node->sda.dev_attr.attr.name; node++)
1087                         sysfs_remove_file(&pdev->dev.kobj,
1088                                           &node->sda.dev_attr.attr);
1089                 kfree(grp->nodes);
1090                 grp->nodes = NULL;
1091         }
1092 }
1093
1094 /*
1095  * applesmc_create_nodes - create a two-dimensional group of sysfs files
1096  */
1097 static int applesmc_create_nodes(struct applesmc_node_group *groups, int num)
1098 {
1099         struct applesmc_node_group *grp;
1100         struct applesmc_dev_attr *node;
1101         struct attribute *attr;
1102         int ret, i;
1103
1104         for (grp = groups; grp->format; grp++) {
1105                 grp->nodes = kcalloc(num + 1, sizeof(*node), GFP_KERNEL);
1106                 if (!grp->nodes) {
1107                         ret = -ENOMEM;
1108                         goto out;
1109                 }
1110                 for (i = 0; i < num; i++) {
1111                         node = &grp->nodes[i];
1112                         scnprintf(node->name, sizeof(node->name), grp->format,
1113                                   i + 1);
1114                         node->sda.index = (grp->option << 16) | (i & 0xffff);
1115                         node->sda.dev_attr.show = grp->show;
1116                         node->sda.dev_attr.store = grp->store;
1117                         attr = &node->sda.dev_attr.attr;
1118                         sysfs_attr_init(attr);
1119                         attr->name = node->name;
1120                         attr->mode = 0444 | (grp->store ? 0200 : 0);
1121                         ret = sysfs_create_file(&pdev->dev.kobj, attr);
1122                         if (ret) {
1123                                 attr->name = NULL;
1124                                 goto out;
1125                         }
1126                 }
1127         }
1128
1129         return 0;
1130 out:
1131         applesmc_destroy_nodes(groups);
1132         return ret;
1133 }
1134
1135 /* Create accelerometer resources */
1136 static int applesmc_create_accelerometer(void)
1137 {
1138         struct input_dev *idev;
1139         int ret;
1140
1141         if (!smcreg.has_accelerometer)
1142                 return 0;
1143
1144         ret = applesmc_create_nodes(accelerometer_group, 1);
1145         if (ret)
1146                 goto out;
1147
1148         applesmc_idev = input_allocate_polled_device();
1149         if (!applesmc_idev) {
1150                 ret = -ENOMEM;
1151                 goto out_sysfs;
1152         }
1153
1154         applesmc_idev->poll = applesmc_idev_poll;
1155         applesmc_idev->poll_interval = APPLESMC_POLL_INTERVAL;
1156
1157         /* initial calibrate for the input device */
1158         applesmc_calibrate();
1159
1160         /* initialize the input device */
1161         idev = applesmc_idev->input;
1162         idev->name = "applesmc";
1163         idev->id.bustype = BUS_HOST;
1164         idev->dev.parent = &pdev->dev;
1165         idev->evbit[0] = BIT_MASK(EV_ABS);
1166         input_set_abs_params(idev, ABS_X,
1167                         -256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
1168         input_set_abs_params(idev, ABS_Y,
1169                         -256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
1170
1171         ret = input_register_polled_device(applesmc_idev);
1172         if (ret)
1173                 goto out_idev;
1174
1175         return 0;
1176
1177 out_idev:
1178         input_free_polled_device(applesmc_idev);
1179
1180 out_sysfs:
1181         applesmc_destroy_nodes(accelerometer_group);
1182
1183 out:
1184         pr_warn("driver init failed (ret=%d)!\n", ret);
1185         return ret;
1186 }
1187
1188 /* Release all resources used by the accelerometer */
1189 static void applesmc_release_accelerometer(void)
1190 {
1191         if (!smcreg.has_accelerometer)
1192                 return;
1193         input_unregister_polled_device(applesmc_idev);
1194         input_free_polled_device(applesmc_idev);
1195         applesmc_destroy_nodes(accelerometer_group);
1196 }
1197
1198 static int applesmc_create_light_sensor(void)
1199 {
1200         if (!smcreg.num_light_sensors)
1201                 return 0;
1202         return applesmc_create_nodes(light_sensor_group, 1);
1203 }
1204
1205 static void applesmc_release_light_sensor(void)
1206 {
1207         if (!smcreg.num_light_sensors)
1208                 return;
1209         applesmc_destroy_nodes(light_sensor_group);
1210 }
1211
1212 static int applesmc_create_key_backlight(void)
1213 {
1214         if (!smcreg.has_key_backlight)
1215                 return 0;
1216         applesmc_led_wq = create_singlethread_workqueue("applesmc-led");
1217         if (!applesmc_led_wq)
1218                 return -ENOMEM;
1219         return led_classdev_register(&pdev->dev, &applesmc_backlight);
1220 }
1221
1222 static void applesmc_release_key_backlight(void)
1223 {
1224         if (!smcreg.has_key_backlight)
1225                 return;
1226         led_classdev_unregister(&applesmc_backlight);
1227         destroy_workqueue(applesmc_led_wq);
1228 }
1229
1230 static int applesmc_dmi_match(const struct dmi_system_id *id)
1231 {
1232         return 1;
1233 }
1234
1235 /*
1236  * Note that DMI_MATCH(...,"MacBook") will match "MacBookPro1,1".
1237  * So we need to put "Apple MacBook Pro" before "Apple MacBook".
1238  */
1239 static const struct dmi_system_id applesmc_whitelist[] __initconst = {
1240         { applesmc_dmi_match, "Apple MacBook Air", {
1241           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1242           DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir") },
1243         },
1244         { applesmc_dmi_match, "Apple MacBook Pro", {
1245           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1246           DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro") },
1247         },
1248         { applesmc_dmi_match, "Apple MacBook", {
1249           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1250           DMI_MATCH(DMI_PRODUCT_NAME, "MacBook") },
1251         },
1252         { applesmc_dmi_match, "Apple Macmini", {
1253           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1254           DMI_MATCH(DMI_PRODUCT_NAME, "Macmini") },
1255         },
1256         { applesmc_dmi_match, "Apple MacPro", {
1257           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1258           DMI_MATCH(DMI_PRODUCT_NAME, "MacPro") },
1259         },
1260         { applesmc_dmi_match, "Apple iMac", {
1261           DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1262           DMI_MATCH(DMI_PRODUCT_NAME, "iMac") },
1263         },
1264         { .ident = NULL }
1265 };
1266
1267 static int __init applesmc_init(void)
1268 {
1269         int ret;
1270
1271         if (!dmi_check_system(applesmc_whitelist)) {
1272                 pr_warn("supported laptop not found!\n");
1273                 ret = -ENODEV;
1274                 goto out;
1275         }
1276
1277         if (!request_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS,
1278                                                                 "applesmc")) {
1279                 ret = -ENXIO;
1280                 goto out;
1281         }
1282
1283         ret = platform_driver_register(&applesmc_driver);
1284         if (ret)
1285                 goto out_region;
1286
1287         pdev = platform_device_register_simple("applesmc", APPLESMC_DATA_PORT,
1288                                                NULL, 0);
1289         if (IS_ERR(pdev)) {
1290                 ret = PTR_ERR(pdev);
1291                 goto out_driver;
1292         }
1293
1294         /* create register cache */
1295         ret = applesmc_init_smcreg();
1296         if (ret)
1297                 goto out_device;
1298
1299         ret = applesmc_create_nodes(info_group, 1);
1300         if (ret)
1301                 goto out_smcreg;
1302
1303         ret = applesmc_create_nodes(fan_group, smcreg.fan_count);
1304         if (ret)
1305                 goto out_info;
1306
1307         ret = applesmc_create_nodes(temp_group, smcreg.index_count);
1308         if (ret)
1309                 goto out_fans;
1310
1311         ret = applesmc_create_accelerometer();
1312         if (ret)
1313                 goto out_temperature;
1314
1315         ret = applesmc_create_light_sensor();
1316         if (ret)
1317                 goto out_accelerometer;
1318
1319         ret = applesmc_create_key_backlight();
1320         if (ret)
1321                 goto out_light_sysfs;
1322
1323         hwmon_dev = hwmon_device_register(&pdev->dev);
1324         if (IS_ERR(hwmon_dev)) {
1325                 ret = PTR_ERR(hwmon_dev);
1326                 goto out_light_ledclass;
1327         }
1328
1329         return 0;
1330
1331 out_light_ledclass:
1332         applesmc_release_key_backlight();
1333 out_light_sysfs:
1334         applesmc_release_light_sensor();
1335 out_accelerometer:
1336         applesmc_release_accelerometer();
1337 out_temperature:
1338         applesmc_destroy_nodes(temp_group);
1339 out_fans:
1340         applesmc_destroy_nodes(fan_group);
1341 out_info:
1342         applesmc_destroy_nodes(info_group);
1343 out_smcreg:
1344         applesmc_destroy_smcreg();
1345 out_device:
1346         platform_device_unregister(pdev);
1347 out_driver:
1348         platform_driver_unregister(&applesmc_driver);
1349 out_region:
1350         release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
1351 out:
1352         pr_warn("driver init failed (ret=%d)!\n", ret);
1353         return ret;
1354 }
1355
1356 static void __exit applesmc_exit(void)
1357 {
1358         hwmon_device_unregister(hwmon_dev);
1359         applesmc_release_key_backlight();
1360         applesmc_release_light_sensor();
1361         applesmc_release_accelerometer();
1362         applesmc_destroy_nodes(temp_group);
1363         applesmc_destroy_nodes(fan_group);
1364         applesmc_destroy_nodes(info_group);
1365         applesmc_destroy_smcreg();
1366         platform_device_unregister(pdev);
1367         platform_driver_unregister(&applesmc_driver);
1368         release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
1369 }
1370
1371 module_init(applesmc_init);
1372 module_exit(applesmc_exit);
1373
1374 MODULE_AUTHOR("Nicolas Boichat");
1375 MODULE_DESCRIPTION("Apple SMC");
1376 MODULE_LICENSE("GPL v2");
1377 MODULE_DEVICE_TABLE(dmi, applesmc_whitelist);