xref: /linux/drivers/hwmon/applesmc.c (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
1 /*
2  * drivers/hwmon/applesmc.c - driver for Apple's SMC (accelerometer, temperature
3  * sensors, fan control, keyboard backlight control) used in Intel-based Apple
4  * computers.
5  *
6  * Copyright (C) 2007 Nicolas Boichat <nicolas@boichat.ch>
7  * Copyright (C) 2010 Henrik Rydberg <rydberg@euromail.se>
8  *
9  * Based on hdaps.c driver:
10  * Copyright (C) 2005 Robert Love <rml@novell.com>
11  * Copyright (C) 2005 Jesper Juhl <jj@chaosbits.net>
12  *
13  * Fan control based on smcFanControl:
14  * Copyright (C) 2006 Hendrik Holtmann <holtmann@mac.com>
15  *
16  * This program is free software; you can redistribute it and/or modify it
17  * under the terms of the GNU General Public License v2 as published by the
18  * Free Software Foundation.
19  *
20  * This program is distributed in the hope that it will be useful, but WITHOUT
21  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
22  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
23  * more details.
24  *
25  * You should have received a copy of the GNU General Public License along with
26  * this program; if not, write to the Free Software Foundation, Inc.,
27  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
28  */
29 
30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31 
32 #include <linux/delay.h>
33 #include <linux/platform_device.h>
34 #include <linux/input-polldev.h>
35 #include <linux/kernel.h>
36 #include <linux/slab.h>
37 #include <linux/module.h>
38 #include <linux/timer.h>
39 #include <linux/dmi.h>
40 #include <linux/mutex.h>
41 #include <linux/hwmon-sysfs.h>
42 #include <linux/io.h>
43 #include <linux/leds.h>
44 #include <linux/hwmon.h>
45 #include <linux/workqueue.h>
46 
47 /* data port used by Apple SMC */
48 #define APPLESMC_DATA_PORT	0x300
49 /* command/status port used by Apple SMC */
50 #define APPLESMC_CMD_PORT	0x304
51 
52 #define APPLESMC_NR_PORTS	32 /* 0x300-0x31f */
53 
54 #define APPLESMC_MAX_DATA_LENGTH 32
55 
56 /* wait up to 32 ms for a status change. */
57 #define APPLESMC_MIN_WAIT	0x0040
58 #define APPLESMC_MAX_WAIT	0x8000
59 
60 #define APPLESMC_STATUS_MASK	0x0f
61 #define APPLESMC_READ_CMD	0x10
62 #define APPLESMC_WRITE_CMD	0x11
63 #define APPLESMC_GET_KEY_BY_INDEX_CMD	0x12
64 #define APPLESMC_GET_KEY_TYPE_CMD	0x13
65 
66 #define KEY_COUNT_KEY		"#KEY" /* r-o ui32 */
67 
68 #define LIGHT_SENSOR_LEFT_KEY	"ALV0" /* r-o {alv (6-10 bytes) */
69 #define LIGHT_SENSOR_RIGHT_KEY	"ALV1" /* r-o {alv (6-10 bytes) */
70 #define BACKLIGHT_KEY		"LKSB" /* w-o {lkb (2 bytes) */
71 
72 #define CLAMSHELL_KEY		"MSLD" /* r-o ui8 (unused) */
73 
74 #define MOTION_SENSOR_X_KEY	"MO_X" /* r-o sp78 (2 bytes) */
75 #define MOTION_SENSOR_Y_KEY	"MO_Y" /* r-o sp78 (2 bytes) */
76 #define MOTION_SENSOR_Z_KEY	"MO_Z" /* r-o sp78 (2 bytes) */
77 #define MOTION_SENSOR_KEY	"MOCN" /* r/w ui16 */
78 
79 #define FANS_COUNT		"FNum" /* r-o ui8 */
80 #define FANS_MANUAL		"FS! " /* r-w ui16 */
81 #define FAN_ID_FMT		"F%dID" /* r-o char[16] */
82 
83 /* List of keys used to read/write fan speeds */
84 static const char *const fan_speed_fmt[] = {
85 	"F%dAc",		/* actual speed */
86 	"F%dMn",		/* minimum speed (rw) */
87 	"F%dMx",		/* maximum speed */
88 	"F%dSf",		/* safe speed - not all models */
89 	"F%dTg",		/* target speed (manual: rw) */
90 };
91 
92 #define INIT_TIMEOUT_MSECS	5000	/* wait up to 5s for device init ... */
93 #define INIT_WAIT_MSECS		50	/* ... in 50ms increments */
94 
95 #define APPLESMC_POLL_INTERVAL	50	/* msecs */
96 #define APPLESMC_INPUT_FUZZ	4	/* input event threshold */
97 #define APPLESMC_INPUT_FLAT	4
98 
99 #define SENSOR_X 0
100 #define SENSOR_Y 1
101 #define SENSOR_Z 2
102 
103 #define to_index(attr) (to_sensor_dev_attr(attr)->index & 0xffff)
104 #define to_option(attr) (to_sensor_dev_attr(attr)->index >> 16)
105 
106 /* Dynamic device node attributes */
107 struct applesmc_dev_attr {
108 	struct sensor_device_attribute sda;	/* hwmon attributes */
109 	char name[32];				/* room for node file name */
110 };
111 
112 /* Dynamic device node group */
113 struct applesmc_node_group {
114 	char *format;				/* format string */
115 	void *show;				/* show function */
116 	void *store;				/* store function */
117 	int option;				/* function argument */
118 	struct applesmc_dev_attr *nodes;	/* dynamic node array */
119 };
120 
121 /* AppleSMC entry - cached register information */
122 struct applesmc_entry {
123 	char key[5];		/* four-letter key code */
124 	u8 valid;		/* set when entry is successfully read once */
125 	u8 len;			/* bounded by APPLESMC_MAX_DATA_LENGTH */
126 	char type[5];		/* four-letter type code */
127 	u8 flags;		/* 0x10: func; 0x40: write; 0x80: read */
128 };
129 
130 /* Register lookup and registers common to all SMCs */
131 static struct applesmc_registers {
132 	struct mutex mutex;		/* register read/write mutex */
133 	unsigned int key_count;		/* number of SMC registers */
134 	unsigned int fan_count;		/* number of fans */
135 	unsigned int temp_count;	/* number of temperature registers */
136 	unsigned int temp_begin;	/* temperature lower index bound */
137 	unsigned int temp_end;		/* temperature upper index bound */
138 	int num_light_sensors;		/* number of light sensors */
139 	bool has_accelerometer;		/* has motion sensor */
140 	bool has_key_backlight;		/* has keyboard backlight */
141 	bool init_complete;		/* true when fully initialized */
142 	struct applesmc_entry *cache;	/* cached key entries */
143 } smcreg = {
144 	.mutex = __MUTEX_INITIALIZER(smcreg.mutex),
145 };
146 
147 static const int debug;
148 static struct platform_device *pdev;
149 static s16 rest_x;
150 static s16 rest_y;
151 static u8 backlight_state[2];
152 
153 static struct device *hwmon_dev;
154 static struct input_polled_dev *applesmc_idev;
155 
156 /*
157  * Last index written to key_at_index sysfs file, and value to use for all other
158  * key_at_index_* sysfs files.
159  */
160 static unsigned int key_at_index;
161 
162 static struct workqueue_struct *applesmc_led_wq;
163 
164 /*
165  * __wait_status - Wait up to 32ms for the status port to get a certain value
166  * (masked with 0x0f), returning zero if the value is obtained.  Callers must
167  * hold applesmc_lock.
168  */
169 static int __wait_status(u8 val)
170 {
171 	int us;
172 
173 	val = val & APPLESMC_STATUS_MASK;
174 
175 	for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
176 		udelay(us);
177 		if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == val)
178 			return 0;
179 	}
180 
181 	return -EIO;
182 }
183 
184 /*
185  * special treatment of command port - on newer macbooks, it seems necessary
186  * to resend the command byte before polling the status again. Callers must
187  * hold applesmc_lock.
188  */
189 static int send_command(u8 cmd)
190 {
191 	int us;
192 	for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
193 		outb(cmd, APPLESMC_CMD_PORT);
194 		udelay(us);
195 		if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == 0x0c)
196 			return 0;
197 	}
198 	return -EIO;
199 }
200 
201 static int send_argument(const char *key)
202 {
203 	int i;
204 
205 	for (i = 0; i < 4; i++) {
206 		outb(key[i], APPLESMC_DATA_PORT);
207 		if (__wait_status(0x04))
208 			return -EIO;
209 	}
210 	return 0;
211 }
212 
213 static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
214 {
215 	int i;
216 
217 	if (send_command(cmd) || send_argument(key)) {
218 		pr_warn("%.4s: read arg fail\n", key);
219 		return -EIO;
220 	}
221 
222 	outb(len, APPLESMC_DATA_PORT);
223 
224 	for (i = 0; i < len; i++) {
225 		if (__wait_status(0x05)) {
226 			pr_warn("%.4s: read data fail\n", key);
227 			return -EIO;
228 		}
229 		buffer[i] = inb(APPLESMC_DATA_PORT);
230 	}
231 
232 	return 0;
233 }
234 
235 static int write_smc(u8 cmd, const char *key, const u8 *buffer, u8 len)
236 {
237 	int i;
238 
239 	if (send_command(cmd) || send_argument(key)) {
240 		pr_warn("%s: write arg fail\n", key);
241 		return -EIO;
242 	}
243 
244 	outb(len, APPLESMC_DATA_PORT);
245 
246 	for (i = 0; i < len; i++) {
247 		if (__wait_status(0x04)) {
248 			pr_warn("%s: write data fail\n", key);
249 			return -EIO;
250 		}
251 		outb(buffer[i], APPLESMC_DATA_PORT);
252 	}
253 
254 	return 0;
255 }
256 
257 static int read_register_count(unsigned int *count)
258 {
259 	__be32 be;
260 	int ret;
261 
262 	ret = read_smc(APPLESMC_READ_CMD, KEY_COUNT_KEY, (u8 *)&be, 4);
263 	if (ret)
264 		return ret;
265 
266 	*count = be32_to_cpu(be);
267 	return 0;
268 }
269 
270 /*
271  * Serialized I/O
272  *
273  * Returns zero on success or a negative error on failure.
274  * All functions below are concurrency safe - callers should NOT hold lock.
275  */
276 
277 static int applesmc_read_entry(const struct applesmc_entry *entry,
278 			       u8 *buf, u8 len)
279 {
280 	int ret;
281 
282 	if (entry->len != len)
283 		return -EINVAL;
284 	mutex_lock(&smcreg.mutex);
285 	ret = read_smc(APPLESMC_READ_CMD, entry->key, buf, len);
286 	mutex_unlock(&smcreg.mutex);
287 
288 	return ret;
289 }
290 
291 static int applesmc_write_entry(const struct applesmc_entry *entry,
292 				const u8 *buf, u8 len)
293 {
294 	int ret;
295 
296 	if (entry->len != len)
297 		return -EINVAL;
298 	mutex_lock(&smcreg.mutex);
299 	ret = write_smc(APPLESMC_WRITE_CMD, entry->key, buf, len);
300 	mutex_unlock(&smcreg.mutex);
301 	return ret;
302 }
303 
304 static const struct applesmc_entry *applesmc_get_entry_by_index(int index)
305 {
306 	struct applesmc_entry *cache = &smcreg.cache[index];
307 	u8 key[4], info[6];
308 	__be32 be;
309 	int ret = 0;
310 
311 	if (cache->valid)
312 		return cache;
313 
314 	mutex_lock(&smcreg.mutex);
315 
316 	if (cache->valid)
317 		goto out;
318 	be = cpu_to_be32(index);
319 	ret = read_smc(APPLESMC_GET_KEY_BY_INDEX_CMD, (u8 *)&be, key, 4);
320 	if (ret)
321 		goto out;
322 	ret = read_smc(APPLESMC_GET_KEY_TYPE_CMD, key, info, 6);
323 	if (ret)
324 		goto out;
325 
326 	memcpy(cache->key, key, 4);
327 	cache->len = info[0];
328 	memcpy(cache->type, &info[1], 4);
329 	cache->flags = info[5];
330 	cache->valid = 1;
331 
332 out:
333 	mutex_unlock(&smcreg.mutex);
334 	if (ret)
335 		return ERR_PTR(ret);
336 	return cache;
337 }
338 
339 static int applesmc_get_lower_bound(unsigned int *lo, const char *key)
340 {
341 	int begin = 0, end = smcreg.key_count;
342 	const struct applesmc_entry *entry;
343 
344 	while (begin != end) {
345 		int middle = begin + (end - begin) / 2;
346 		entry = applesmc_get_entry_by_index(middle);
347 		if (IS_ERR(entry)) {
348 			*lo = 0;
349 			return PTR_ERR(entry);
350 		}
351 		if (strcmp(entry->key, key) < 0)
352 			begin = middle + 1;
353 		else
354 			end = middle;
355 	}
356 
357 	*lo = begin;
358 	return 0;
359 }
360 
361 static int applesmc_get_upper_bound(unsigned int *hi, const char *key)
362 {
363 	int begin = 0, end = smcreg.key_count;
364 	const struct applesmc_entry *entry;
365 
366 	while (begin != end) {
367 		int middle = begin + (end - begin) / 2;
368 		entry = applesmc_get_entry_by_index(middle);
369 		if (IS_ERR(entry)) {
370 			*hi = smcreg.key_count;
371 			return PTR_ERR(entry);
372 		}
373 		if (strcmp(key, entry->key) < 0)
374 			end = middle;
375 		else
376 			begin = middle + 1;
377 	}
378 
379 	*hi = begin;
380 	return 0;
381 }
382 
383 static const struct applesmc_entry *applesmc_get_entry_by_key(const char *key)
384 {
385 	int begin, end;
386 	int ret;
387 
388 	ret = applesmc_get_lower_bound(&begin, key);
389 	if (ret)
390 		return ERR_PTR(ret);
391 	ret = applesmc_get_upper_bound(&end, key);
392 	if (ret)
393 		return ERR_PTR(ret);
394 	if (end - begin != 1)
395 		return ERR_PTR(-EINVAL);
396 
397 	return applesmc_get_entry_by_index(begin);
398 }
399 
400 static int applesmc_read_key(const char *key, u8 *buffer, u8 len)
401 {
402 	const struct applesmc_entry *entry;
403 
404 	entry = applesmc_get_entry_by_key(key);
405 	if (IS_ERR(entry))
406 		return PTR_ERR(entry);
407 
408 	return applesmc_read_entry(entry, buffer, len);
409 }
410 
411 static int applesmc_write_key(const char *key, const u8 *buffer, u8 len)
412 {
413 	const struct applesmc_entry *entry;
414 
415 	entry = applesmc_get_entry_by_key(key);
416 	if (IS_ERR(entry))
417 		return PTR_ERR(entry);
418 
419 	return applesmc_write_entry(entry, buffer, len);
420 }
421 
422 static int applesmc_has_key(const char *key, bool *value)
423 {
424 	const struct applesmc_entry *entry;
425 
426 	entry = applesmc_get_entry_by_key(key);
427 	if (IS_ERR(entry) && PTR_ERR(entry) != -EINVAL)
428 		return PTR_ERR(entry);
429 
430 	*value = !IS_ERR(entry);
431 	return 0;
432 }
433 
434 /*
435  * applesmc_read_motion_sensor - Read motion sensor (X, Y or Z).
436  */
437 static int applesmc_read_motion_sensor(int index, s16 *value)
438 {
439 	u8 buffer[2];
440 	int ret;
441 
442 	switch (index) {
443 	case SENSOR_X:
444 		ret = applesmc_read_key(MOTION_SENSOR_X_KEY, buffer, 2);
445 		break;
446 	case SENSOR_Y:
447 		ret = applesmc_read_key(MOTION_SENSOR_Y_KEY, buffer, 2);
448 		break;
449 	case SENSOR_Z:
450 		ret = applesmc_read_key(MOTION_SENSOR_Z_KEY, buffer, 2);
451 		break;
452 	default:
453 		ret = -EINVAL;
454 	}
455 
456 	*value = ((s16)buffer[0] << 8) | buffer[1];
457 
458 	return ret;
459 }
460 
461 /*
462  * applesmc_device_init - initialize the accelerometer.  Can sleep.
463  */
464 static void applesmc_device_init(void)
465 {
466 	int total;
467 	u8 buffer[2];
468 
469 	if (!smcreg.has_accelerometer)
470 		return;
471 
472 	for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
473 		if (!applesmc_read_key(MOTION_SENSOR_KEY, buffer, 2) &&
474 				(buffer[0] != 0x00 || buffer[1] != 0x00))
475 			return;
476 		buffer[0] = 0xe0;
477 		buffer[1] = 0x00;
478 		applesmc_write_key(MOTION_SENSOR_KEY, buffer, 2);
479 		msleep(INIT_WAIT_MSECS);
480 	}
481 
482 	pr_warn("failed to init the device\n");
483 }
484 
485 /*
486  * applesmc_init_smcreg_try - Try to initialize register cache. Idempotent.
487  */
488 static int applesmc_init_smcreg_try(void)
489 {
490 	struct applesmc_registers *s = &smcreg;
491 	bool left_light_sensor, right_light_sensor;
492 	u8 tmp[1];
493 	int ret;
494 
495 	if (s->init_complete)
496 		return 0;
497 
498 	ret = read_register_count(&s->key_count);
499 	if (ret)
500 		return ret;
501 
502 	if (!s->cache)
503 		s->cache = kcalloc(s->key_count, sizeof(*s->cache), GFP_KERNEL);
504 	if (!s->cache)
505 		return -ENOMEM;
506 
507 	ret = applesmc_read_key(FANS_COUNT, tmp, 1);
508 	if (ret)
509 		return ret;
510 	s->fan_count = tmp[0];
511 
512 	ret = applesmc_get_lower_bound(&s->temp_begin, "T");
513 	if (ret)
514 		return ret;
515 	ret = applesmc_get_lower_bound(&s->temp_end, "U");
516 	if (ret)
517 		return ret;
518 	s->temp_count = s->temp_end - s->temp_begin;
519 
520 	ret = applesmc_has_key(LIGHT_SENSOR_LEFT_KEY, &left_light_sensor);
521 	if (ret)
522 		return ret;
523 	ret = applesmc_has_key(LIGHT_SENSOR_RIGHT_KEY, &right_light_sensor);
524 	if (ret)
525 		return ret;
526 	ret = applesmc_has_key(MOTION_SENSOR_KEY, &s->has_accelerometer);
527 	if (ret)
528 		return ret;
529 	ret = applesmc_has_key(BACKLIGHT_KEY, &s->has_key_backlight);
530 	if (ret)
531 		return ret;
532 
533 	s->num_light_sensors = left_light_sensor + right_light_sensor;
534 	s->init_complete = true;
535 
536 	pr_info("key=%d fan=%d temp=%d acc=%d lux=%d kbd=%d\n",
537 	       s->key_count, s->fan_count, s->temp_count,
538 	       s->has_accelerometer,
539 	       s->num_light_sensors,
540 	       s->has_key_backlight);
541 
542 	return 0;
543 }
544 
545 /*
546  * applesmc_init_smcreg - Initialize register cache.
547  *
548  * Retries until initialization is successful, or the operation times out.
549  *
550  */
551 static int applesmc_init_smcreg(void)
552 {
553 	int ms, ret;
554 
555 	for (ms = 0; ms < INIT_TIMEOUT_MSECS; ms += INIT_WAIT_MSECS) {
556 		ret = applesmc_init_smcreg_try();
557 		if (!ret) {
558 			if (ms)
559 				pr_info("init_smcreg() took %d ms\n", ms);
560 			return 0;
561 		}
562 		msleep(INIT_WAIT_MSECS);
563 	}
564 
565 	kfree(smcreg.cache);
566 	smcreg.cache = NULL;
567 
568 	return ret;
569 }
570 
571 static void applesmc_destroy_smcreg(void)
572 {
573 	kfree(smcreg.cache);
574 	smcreg.cache = NULL;
575 	smcreg.init_complete = false;
576 }
577 
578 /* Device model stuff */
579 static int applesmc_probe(struct platform_device *dev)
580 {
581 	int ret;
582 
583 	ret = applesmc_init_smcreg();
584 	if (ret)
585 		return ret;
586 
587 	applesmc_device_init();
588 
589 	return 0;
590 }
591 
592 /* Synchronize device with memorized backlight state */
593 static int applesmc_pm_resume(struct device *dev)
594 {
595 	if (smcreg.has_key_backlight)
596 		applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
597 	return 0;
598 }
599 
600 /* Reinitialize device on resume from hibernation */
601 static int applesmc_pm_restore(struct device *dev)
602 {
603 	applesmc_device_init();
604 	return applesmc_pm_resume(dev);
605 }
606 
607 static const struct dev_pm_ops applesmc_pm_ops = {
608 	.resume = applesmc_pm_resume,
609 	.restore = applesmc_pm_restore,
610 };
611 
612 static struct platform_driver applesmc_driver = {
613 	.probe = applesmc_probe,
614 	.driver	= {
615 		.name = "applesmc",
616 		.owner = THIS_MODULE,
617 		.pm = &applesmc_pm_ops,
618 	},
619 };
620 
621 /*
622  * applesmc_calibrate - Set our "resting" values.  Callers must
623  * hold applesmc_lock.
624  */
625 static void applesmc_calibrate(void)
626 {
627 	applesmc_read_motion_sensor(SENSOR_X, &rest_x);
628 	applesmc_read_motion_sensor(SENSOR_Y, &rest_y);
629 	rest_x = -rest_x;
630 }
631 
632 static void applesmc_idev_poll(struct input_polled_dev *dev)
633 {
634 	struct input_dev *idev = dev->input;
635 	s16 x, y;
636 
637 	if (applesmc_read_motion_sensor(SENSOR_X, &x))
638 		return;
639 	if (applesmc_read_motion_sensor(SENSOR_Y, &y))
640 		return;
641 
642 	x = -x;
643 	input_report_abs(idev, ABS_X, x - rest_x);
644 	input_report_abs(idev, ABS_Y, y - rest_y);
645 	input_sync(idev);
646 }
647 
648 /* Sysfs Files */
649 
650 static ssize_t applesmc_name_show(struct device *dev,
651 				   struct device_attribute *attr, char *buf)
652 {
653 	return snprintf(buf, PAGE_SIZE, "applesmc\n");
654 }
655 
656 static ssize_t applesmc_position_show(struct device *dev,
657 				   struct device_attribute *attr, char *buf)
658 {
659 	int ret;
660 	s16 x, y, z;
661 
662 	ret = applesmc_read_motion_sensor(SENSOR_X, &x);
663 	if (ret)
664 		goto out;
665 	ret = applesmc_read_motion_sensor(SENSOR_Y, &y);
666 	if (ret)
667 		goto out;
668 	ret = applesmc_read_motion_sensor(SENSOR_Z, &z);
669 	if (ret)
670 		goto out;
671 
672 out:
673 	if (ret)
674 		return ret;
675 	else
676 		return snprintf(buf, PAGE_SIZE, "(%d,%d,%d)\n", x, y, z);
677 }
678 
679 static ssize_t applesmc_light_show(struct device *dev,
680 				struct device_attribute *attr, char *sysfsbuf)
681 {
682 	const struct applesmc_entry *entry;
683 	static int data_length;
684 	int ret;
685 	u8 left = 0, right = 0;
686 	u8 buffer[10];
687 
688 	if (!data_length) {
689 		entry = applesmc_get_entry_by_key(LIGHT_SENSOR_LEFT_KEY);
690 		if (IS_ERR(entry))
691 			return PTR_ERR(entry);
692 		if (entry->len > 10)
693 			return -ENXIO;
694 		data_length = entry->len;
695 		pr_info("light sensor data length set to %d\n", data_length);
696 	}
697 
698 	ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, buffer, data_length);
699 	/* newer macbooks report a single 10-bit bigendian value */
700 	if (data_length == 10) {
701 		left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2;
702 		goto out;
703 	}
704 	left = buffer[2];
705 	if (ret)
706 		goto out;
707 	ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length);
708 	right = buffer[2];
709 
710 out:
711 	if (ret)
712 		return ret;
713 	else
714 		return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", left, right);
715 }
716 
717 /* Displays sensor key as label */
718 static ssize_t applesmc_show_sensor_label(struct device *dev,
719 			struct device_attribute *devattr, char *sysfsbuf)
720 {
721 	int index = smcreg.temp_begin + to_index(devattr);
722 	const struct applesmc_entry *entry;
723 
724 	entry = applesmc_get_entry_by_index(index);
725 	if (IS_ERR(entry))
726 		return PTR_ERR(entry);
727 
728 	return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
729 }
730 
731 /* Displays degree Celsius * 1000 */
732 static ssize_t applesmc_show_temperature(struct device *dev,
733 			struct device_attribute *devattr, char *sysfsbuf)
734 {
735 	int index = smcreg.temp_begin + to_index(devattr);
736 	const struct applesmc_entry *entry;
737 	int ret;
738 	u8 buffer[2];
739 	unsigned int temp;
740 
741 	entry = applesmc_get_entry_by_index(index);
742 	if (IS_ERR(entry))
743 		return PTR_ERR(entry);
744 	if (entry->len > 2)
745 		return -EINVAL;
746 
747 	ret = applesmc_read_entry(entry, buffer, entry->len);
748 	if (ret)
749 		return ret;
750 
751 	if (entry->len == 2) {
752 		temp = buffer[0] * 1000;
753 		temp += (buffer[1] >> 6) * 250;
754 	} else {
755 		temp = buffer[0] * 4000;
756 	}
757 
758 	return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", temp);
759 }
760 
761 static ssize_t applesmc_show_fan_speed(struct device *dev,
762 				struct device_attribute *attr, char *sysfsbuf)
763 {
764 	int ret;
765 	unsigned int speed = 0;
766 	char newkey[5];
767 	u8 buffer[2];
768 
769 	sprintf(newkey, fan_speed_fmt[to_option(attr)], to_index(attr));
770 
771 	ret = applesmc_read_key(newkey, buffer, 2);
772 	speed = ((buffer[0] << 8 | buffer[1]) >> 2);
773 
774 	if (ret)
775 		return ret;
776 	else
777 		return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
778 }
779 
780 static ssize_t applesmc_store_fan_speed(struct device *dev,
781 					struct device_attribute *attr,
782 					const char *sysfsbuf, size_t count)
783 {
784 	int ret;
785 	unsigned long speed;
786 	char newkey[5];
787 	u8 buffer[2];
788 
789 	if (kstrtoul(sysfsbuf, 10, &speed) < 0 || speed >= 0x4000)
790 		return -EINVAL;		/* Bigger than a 14-bit value */
791 
792 	sprintf(newkey, fan_speed_fmt[to_option(attr)], to_index(attr));
793 
794 	buffer[0] = (speed >> 6) & 0xff;
795 	buffer[1] = (speed << 2) & 0xff;
796 	ret = applesmc_write_key(newkey, buffer, 2);
797 
798 	if (ret)
799 		return ret;
800 	else
801 		return count;
802 }
803 
804 static ssize_t applesmc_show_fan_manual(struct device *dev,
805 			struct device_attribute *attr, char *sysfsbuf)
806 {
807 	int ret;
808 	u16 manual = 0;
809 	u8 buffer[2];
810 
811 	ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
812 	manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01;
813 
814 	if (ret)
815 		return ret;
816 	else
817 		return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
818 }
819 
820 static ssize_t applesmc_store_fan_manual(struct device *dev,
821 					 struct device_attribute *attr,
822 					 const char *sysfsbuf, size_t count)
823 {
824 	int ret;
825 	u8 buffer[2];
826 	unsigned long input;
827 	u16 val;
828 
829 	if (kstrtoul(sysfsbuf, 10, &input) < 0)
830 		return -EINVAL;
831 
832 	ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
833 	val = (buffer[0] << 8 | buffer[1]);
834 	if (ret)
835 		goto out;
836 
837 	if (input)
838 		val = val | (0x01 << to_index(attr));
839 	else
840 		val = val & ~(0x01 << to_index(attr));
841 
842 	buffer[0] = (val >> 8) & 0xFF;
843 	buffer[1] = val & 0xFF;
844 
845 	ret = applesmc_write_key(FANS_MANUAL, buffer, 2);
846 
847 out:
848 	if (ret)
849 		return ret;
850 	else
851 		return count;
852 }
853 
854 static ssize_t applesmc_show_fan_position(struct device *dev,
855 				struct device_attribute *attr, char *sysfsbuf)
856 {
857 	int ret;
858 	char newkey[5];
859 	u8 buffer[17];
860 
861 	sprintf(newkey, FAN_ID_FMT, to_index(attr));
862 
863 	ret = applesmc_read_key(newkey, buffer, 16);
864 	buffer[16] = 0;
865 
866 	if (ret)
867 		return ret;
868 	else
869 		return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", buffer+4);
870 }
871 
872 static ssize_t applesmc_calibrate_show(struct device *dev,
873 				struct device_attribute *attr, char *sysfsbuf)
874 {
875 	return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", rest_x, rest_y);
876 }
877 
878 static ssize_t applesmc_calibrate_store(struct device *dev,
879 	struct device_attribute *attr, const char *sysfsbuf, size_t count)
880 {
881 	applesmc_calibrate();
882 
883 	return count;
884 }
885 
886 static void applesmc_backlight_set(struct work_struct *work)
887 {
888 	applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
889 }
890 static DECLARE_WORK(backlight_work, &applesmc_backlight_set);
891 
892 static void applesmc_brightness_set(struct led_classdev *led_cdev,
893 						enum led_brightness value)
894 {
895 	int ret;
896 
897 	backlight_state[0] = value;
898 	ret = queue_work(applesmc_led_wq, &backlight_work);
899 
900 	if (debug && (!ret))
901 		printk(KERN_DEBUG "applesmc: work was already on the queue.\n");
902 }
903 
904 static ssize_t applesmc_key_count_show(struct device *dev,
905 				struct device_attribute *attr, char *sysfsbuf)
906 {
907 	int ret;
908 	u8 buffer[4];
909 	u32 count;
910 
911 	ret = applesmc_read_key(KEY_COUNT_KEY, buffer, 4);
912 	count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
913 						((u32)buffer[2]<<8) + buffer[3];
914 
915 	if (ret)
916 		return ret;
917 	else
918 		return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
919 }
920 
921 static ssize_t applesmc_key_at_index_read_show(struct device *dev,
922 				struct device_attribute *attr, char *sysfsbuf)
923 {
924 	const struct applesmc_entry *entry;
925 	int ret;
926 
927 	entry = applesmc_get_entry_by_index(key_at_index);
928 	if (IS_ERR(entry))
929 		return PTR_ERR(entry);
930 	ret = applesmc_read_entry(entry, sysfsbuf, entry->len);
931 	if (ret)
932 		return ret;
933 
934 	return entry->len;
935 }
936 
937 static ssize_t applesmc_key_at_index_data_length_show(struct device *dev,
938 				struct device_attribute *attr, char *sysfsbuf)
939 {
940 	const struct applesmc_entry *entry;
941 
942 	entry = applesmc_get_entry_by_index(key_at_index);
943 	if (IS_ERR(entry))
944 		return PTR_ERR(entry);
945 
946 	return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", entry->len);
947 }
948 
949 static ssize_t applesmc_key_at_index_type_show(struct device *dev,
950 				struct device_attribute *attr, char *sysfsbuf)
951 {
952 	const struct applesmc_entry *entry;
953 
954 	entry = applesmc_get_entry_by_index(key_at_index);
955 	if (IS_ERR(entry))
956 		return PTR_ERR(entry);
957 
958 	return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->type);
959 }
960 
961 static ssize_t applesmc_key_at_index_name_show(struct device *dev,
962 				struct device_attribute *attr, char *sysfsbuf)
963 {
964 	const struct applesmc_entry *entry;
965 
966 	entry = applesmc_get_entry_by_index(key_at_index);
967 	if (IS_ERR(entry))
968 		return PTR_ERR(entry);
969 
970 	return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
971 }
972 
973 static ssize_t applesmc_key_at_index_show(struct device *dev,
974 				struct device_attribute *attr, char *sysfsbuf)
975 {
976 	return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", key_at_index);
977 }
978 
979 static ssize_t applesmc_key_at_index_store(struct device *dev,
980 	struct device_attribute *attr, const char *sysfsbuf, size_t count)
981 {
982 	unsigned long newkey;
983 
984 	if (kstrtoul(sysfsbuf, 10, &newkey) < 0
985 	    || newkey >= smcreg.key_count)
986 		return -EINVAL;
987 
988 	key_at_index = newkey;
989 	return count;
990 }
991 
992 static struct led_classdev applesmc_backlight = {
993 	.name			= "smc::kbd_backlight",
994 	.default_trigger	= "nand-disk",
995 	.brightness_set		= applesmc_brightness_set,
996 };
997 
998 static struct applesmc_node_group info_group[] = {
999 	{ "name", applesmc_name_show },
1000 	{ "key_count", applesmc_key_count_show },
1001 	{ "key_at_index", applesmc_key_at_index_show, applesmc_key_at_index_store },
1002 	{ "key_at_index_name", applesmc_key_at_index_name_show },
1003 	{ "key_at_index_type", applesmc_key_at_index_type_show },
1004 	{ "key_at_index_data_length", applesmc_key_at_index_data_length_show },
1005 	{ "key_at_index_data", applesmc_key_at_index_read_show },
1006 	{ }
1007 };
1008 
1009 static struct applesmc_node_group accelerometer_group[] = {
1010 	{ "position", applesmc_position_show },
1011 	{ "calibrate", applesmc_calibrate_show, applesmc_calibrate_store },
1012 	{ }
1013 };
1014 
1015 static struct applesmc_node_group light_sensor_group[] = {
1016 	{ "light", applesmc_light_show },
1017 	{ }
1018 };
1019 
1020 static struct applesmc_node_group fan_group[] = {
1021 	{ "fan%d_label", applesmc_show_fan_position },
1022 	{ "fan%d_input", applesmc_show_fan_speed, NULL, 0 },
1023 	{ "fan%d_min", applesmc_show_fan_speed, applesmc_store_fan_speed, 1 },
1024 	{ "fan%d_max", applesmc_show_fan_speed, NULL, 2 },
1025 	{ "fan%d_safe", applesmc_show_fan_speed, NULL, 3 },
1026 	{ "fan%d_output", applesmc_show_fan_speed, applesmc_store_fan_speed, 4 },
1027 	{ "fan%d_manual", applesmc_show_fan_manual, applesmc_store_fan_manual },
1028 	{ }
1029 };
1030 
1031 static struct applesmc_node_group temp_group[] = {
1032 	{ "temp%d_label", applesmc_show_sensor_label },
1033 	{ "temp%d_input", applesmc_show_temperature },
1034 	{ }
1035 };
1036 
1037 /* Module stuff */
1038 
1039 /*
1040  * applesmc_destroy_nodes - remove files and free associated memory
1041  */
1042 static void applesmc_destroy_nodes(struct applesmc_node_group *groups)
1043 {
1044 	struct applesmc_node_group *grp;
1045 	struct applesmc_dev_attr *node;
1046 
1047 	for (grp = groups; grp->nodes; grp++) {
1048 		for (node = grp->nodes; node->sda.dev_attr.attr.name; node++)
1049 			sysfs_remove_file(&pdev->dev.kobj,
1050 					  &node->sda.dev_attr.attr);
1051 		kfree(grp->nodes);
1052 		grp->nodes = NULL;
1053 	}
1054 }
1055 
1056 /*
1057  * applesmc_create_nodes - create a two-dimensional group of sysfs files
1058  */
1059 static int applesmc_create_nodes(struct applesmc_node_group *groups, int num)
1060 {
1061 	struct applesmc_node_group *grp;
1062 	struct applesmc_dev_attr *node;
1063 	struct attribute *attr;
1064 	int ret, i;
1065 
1066 	for (grp = groups; grp->format; grp++) {
1067 		grp->nodes = kcalloc(num + 1, sizeof(*node), GFP_KERNEL);
1068 		if (!grp->nodes) {
1069 			ret = -ENOMEM;
1070 			goto out;
1071 		}
1072 		for (i = 0; i < num; i++) {
1073 			node = &grp->nodes[i];
1074 			sprintf(node->name, grp->format, i + 1);
1075 			node->sda.index = (grp->option << 16) | (i & 0xffff);
1076 			node->sda.dev_attr.show = grp->show;
1077 			node->sda.dev_attr.store = grp->store;
1078 			attr = &node->sda.dev_attr.attr;
1079 			sysfs_attr_init(attr);
1080 			attr->name = node->name;
1081 			attr->mode = S_IRUGO | (grp->store ? S_IWUSR : 0);
1082 			ret = sysfs_create_file(&pdev->dev.kobj, attr);
1083 			if (ret) {
1084 				attr->name = NULL;
1085 				goto out;
1086 			}
1087 		}
1088 	}
1089 
1090 	return 0;
1091 out:
1092 	applesmc_destroy_nodes(groups);
1093 	return ret;
1094 }
1095 
1096 /* Create accelerometer ressources */
1097 static int applesmc_create_accelerometer(void)
1098 {
1099 	struct input_dev *idev;
1100 	int ret;
1101 
1102 	if (!smcreg.has_accelerometer)
1103 		return 0;
1104 
1105 	ret = applesmc_create_nodes(accelerometer_group, 1);
1106 	if (ret)
1107 		goto out;
1108 
1109 	applesmc_idev = input_allocate_polled_device();
1110 	if (!applesmc_idev) {
1111 		ret = -ENOMEM;
1112 		goto out_sysfs;
1113 	}
1114 
1115 	applesmc_idev->poll = applesmc_idev_poll;
1116 	applesmc_idev->poll_interval = APPLESMC_POLL_INTERVAL;
1117 
1118 	/* initial calibrate for the input device */
1119 	applesmc_calibrate();
1120 
1121 	/* initialize the input device */
1122 	idev = applesmc_idev->input;
1123 	idev->name = "applesmc";
1124 	idev->id.bustype = BUS_HOST;
1125 	idev->dev.parent = &pdev->dev;
1126 	idev->evbit[0] = BIT_MASK(EV_ABS);
1127 	input_set_abs_params(idev, ABS_X,
1128 			-256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
1129 	input_set_abs_params(idev, ABS_Y,
1130 			-256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
1131 
1132 	ret = input_register_polled_device(applesmc_idev);
1133 	if (ret)
1134 		goto out_idev;
1135 
1136 	return 0;
1137 
1138 out_idev:
1139 	input_free_polled_device(applesmc_idev);
1140 
1141 out_sysfs:
1142 	applesmc_destroy_nodes(accelerometer_group);
1143 
1144 out:
1145 	pr_warn("driver init failed (ret=%d)!\n", ret);
1146 	return ret;
1147 }
1148 
1149 /* Release all ressources used by the accelerometer */
1150 static void applesmc_release_accelerometer(void)
1151 {
1152 	if (!smcreg.has_accelerometer)
1153 		return;
1154 	input_unregister_polled_device(applesmc_idev);
1155 	input_free_polled_device(applesmc_idev);
1156 	applesmc_destroy_nodes(accelerometer_group);
1157 }
1158 
1159 static int applesmc_create_light_sensor(void)
1160 {
1161 	if (!smcreg.num_light_sensors)
1162 		return 0;
1163 	return applesmc_create_nodes(light_sensor_group, 1);
1164 }
1165 
1166 static void applesmc_release_light_sensor(void)
1167 {
1168 	if (!smcreg.num_light_sensors)
1169 		return;
1170 	applesmc_destroy_nodes(light_sensor_group);
1171 }
1172 
1173 static int applesmc_create_key_backlight(void)
1174 {
1175 	if (!smcreg.has_key_backlight)
1176 		return 0;
1177 	applesmc_led_wq = create_singlethread_workqueue("applesmc-led");
1178 	if (!applesmc_led_wq)
1179 		return -ENOMEM;
1180 	return led_classdev_register(&pdev->dev, &applesmc_backlight);
1181 }
1182 
1183 static void applesmc_release_key_backlight(void)
1184 {
1185 	if (!smcreg.has_key_backlight)
1186 		return;
1187 	led_classdev_unregister(&applesmc_backlight);
1188 	destroy_workqueue(applesmc_led_wq);
1189 }
1190 
1191 static int applesmc_dmi_match(const struct dmi_system_id *id)
1192 {
1193 	return 1;
1194 }
1195 
1196 /*
1197  * Note that DMI_MATCH(...,"MacBook") will match "MacBookPro1,1".
1198  * So we need to put "Apple MacBook Pro" before "Apple MacBook".
1199  */
1200 static __initdata struct dmi_system_id applesmc_whitelist[] = {
1201 	{ applesmc_dmi_match, "Apple MacBook Air", {
1202 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1203 	  DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir") },
1204 	},
1205 	{ applesmc_dmi_match, "Apple MacBook Pro", {
1206 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1207 	  DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro") },
1208 	},
1209 	{ applesmc_dmi_match, "Apple MacBook", {
1210 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1211 	  DMI_MATCH(DMI_PRODUCT_NAME, "MacBook") },
1212 	},
1213 	{ applesmc_dmi_match, "Apple Macmini", {
1214 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1215 	  DMI_MATCH(DMI_PRODUCT_NAME, "Macmini") },
1216 	},
1217 	{ applesmc_dmi_match, "Apple MacPro", {
1218 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1219 	  DMI_MATCH(DMI_PRODUCT_NAME, "MacPro") },
1220 	},
1221 	{ applesmc_dmi_match, "Apple iMac", {
1222 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1223 	  DMI_MATCH(DMI_PRODUCT_NAME, "iMac") },
1224 	},
1225 	{ .ident = NULL }
1226 };
1227 
1228 static int __init applesmc_init(void)
1229 {
1230 	int ret;
1231 
1232 	if (!dmi_check_system(applesmc_whitelist)) {
1233 		pr_warn("supported laptop not found!\n");
1234 		ret = -ENODEV;
1235 		goto out;
1236 	}
1237 
1238 	if (!request_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS,
1239 								"applesmc")) {
1240 		ret = -ENXIO;
1241 		goto out;
1242 	}
1243 
1244 	ret = platform_driver_register(&applesmc_driver);
1245 	if (ret)
1246 		goto out_region;
1247 
1248 	pdev = platform_device_register_simple("applesmc", APPLESMC_DATA_PORT,
1249 					       NULL, 0);
1250 	if (IS_ERR(pdev)) {
1251 		ret = PTR_ERR(pdev);
1252 		goto out_driver;
1253 	}
1254 
1255 	/* create register cache */
1256 	ret = applesmc_init_smcreg();
1257 	if (ret)
1258 		goto out_device;
1259 
1260 	ret = applesmc_create_nodes(info_group, 1);
1261 	if (ret)
1262 		goto out_smcreg;
1263 
1264 	ret = applesmc_create_nodes(fan_group, smcreg.fan_count);
1265 	if (ret)
1266 		goto out_info;
1267 
1268 	ret = applesmc_create_nodes(temp_group, smcreg.temp_count);
1269 	if (ret)
1270 		goto out_fans;
1271 
1272 	ret = applesmc_create_accelerometer();
1273 	if (ret)
1274 		goto out_temperature;
1275 
1276 	ret = applesmc_create_light_sensor();
1277 	if (ret)
1278 		goto out_accelerometer;
1279 
1280 	ret = applesmc_create_key_backlight();
1281 	if (ret)
1282 		goto out_light_sysfs;
1283 
1284 	hwmon_dev = hwmon_device_register(&pdev->dev);
1285 	if (IS_ERR(hwmon_dev)) {
1286 		ret = PTR_ERR(hwmon_dev);
1287 		goto out_light_ledclass;
1288 	}
1289 
1290 	return 0;
1291 
1292 out_light_ledclass:
1293 	applesmc_release_key_backlight();
1294 out_light_sysfs:
1295 	applesmc_release_light_sensor();
1296 out_accelerometer:
1297 	applesmc_release_accelerometer();
1298 out_temperature:
1299 	applesmc_destroy_nodes(temp_group);
1300 out_fans:
1301 	applesmc_destroy_nodes(fan_group);
1302 out_info:
1303 	applesmc_destroy_nodes(info_group);
1304 out_smcreg:
1305 	applesmc_destroy_smcreg();
1306 out_device:
1307 	platform_device_unregister(pdev);
1308 out_driver:
1309 	platform_driver_unregister(&applesmc_driver);
1310 out_region:
1311 	release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
1312 out:
1313 	pr_warn("driver init failed (ret=%d)!\n", ret);
1314 	return ret;
1315 }
1316 
1317 static void __exit applesmc_exit(void)
1318 {
1319 	hwmon_device_unregister(hwmon_dev);
1320 	applesmc_release_key_backlight();
1321 	applesmc_release_light_sensor();
1322 	applesmc_release_accelerometer();
1323 	applesmc_destroy_nodes(temp_group);
1324 	applesmc_destroy_nodes(fan_group);
1325 	applesmc_destroy_nodes(info_group);
1326 	applesmc_destroy_smcreg();
1327 	platform_device_unregister(pdev);
1328 	platform_driver_unregister(&applesmc_driver);
1329 	release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
1330 }
1331 
1332 module_init(applesmc_init);
1333 module_exit(applesmc_exit);
1334 
1335 MODULE_AUTHOR("Nicolas Boichat");
1336 MODULE_DESCRIPTION("Apple SMC");
1337 MODULE_LICENSE("GPL v2");
1338 MODULE_DEVICE_TABLE(dmi, applesmc_whitelist);
1339