xref: /openbmc/linux/drivers/hwmon/applesmc.c (revision ff56535d)
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 <jesper.juhl@gmail.com>
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("%s: 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("%s: 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 			return PTR_ERR(entry);
349 		if (strcmp(entry->key, key) < 0)
350 			begin = middle + 1;
351 		else
352 			end = middle;
353 	}
354 
355 	*lo = begin;
356 	return 0;
357 }
358 
359 static int applesmc_get_upper_bound(unsigned int *hi, const char *key)
360 {
361 	int begin = 0, end = smcreg.key_count;
362 	const struct applesmc_entry *entry;
363 
364 	while (begin != end) {
365 		int middle = begin + (end - begin) / 2;
366 		entry = applesmc_get_entry_by_index(middle);
367 		if (IS_ERR(entry))
368 			return PTR_ERR(entry);
369 		if (strcmp(key, entry->key) < 0)
370 			end = middle;
371 		else
372 			begin = middle + 1;
373 	}
374 
375 	*hi = begin;
376 	return 0;
377 }
378 
379 static const struct applesmc_entry *applesmc_get_entry_by_key(const char *key)
380 {
381 	int begin, end;
382 	int ret;
383 
384 	ret = applesmc_get_lower_bound(&begin, key);
385 	if (ret)
386 		return ERR_PTR(ret);
387 	ret = applesmc_get_upper_bound(&end, key);
388 	if (ret)
389 		return ERR_PTR(ret);
390 	if (end - begin != 1)
391 		return ERR_PTR(-EINVAL);
392 
393 	return applesmc_get_entry_by_index(begin);
394 }
395 
396 static int applesmc_read_key(const char *key, u8 *buffer, u8 len)
397 {
398 	const struct applesmc_entry *entry;
399 
400 	entry = applesmc_get_entry_by_key(key);
401 	if (IS_ERR(entry))
402 		return PTR_ERR(entry);
403 
404 	return applesmc_read_entry(entry, buffer, len);
405 }
406 
407 static int applesmc_write_key(const char *key, const u8 *buffer, u8 len)
408 {
409 	const struct applesmc_entry *entry;
410 
411 	entry = applesmc_get_entry_by_key(key);
412 	if (IS_ERR(entry))
413 		return PTR_ERR(entry);
414 
415 	return applesmc_write_entry(entry, buffer, len);
416 }
417 
418 static int applesmc_has_key(const char *key, bool *value)
419 {
420 	const struct applesmc_entry *entry;
421 
422 	entry = applesmc_get_entry_by_key(key);
423 	if (IS_ERR(entry) && PTR_ERR(entry) != -EINVAL)
424 		return PTR_ERR(entry);
425 
426 	*value = !IS_ERR(entry);
427 	return 0;
428 }
429 
430 /*
431  * applesmc_read_motion_sensor - Read motion sensor (X, Y or Z).
432  */
433 static int applesmc_read_motion_sensor(int index, s16 *value)
434 {
435 	u8 buffer[2];
436 	int ret;
437 
438 	switch (index) {
439 	case SENSOR_X:
440 		ret = applesmc_read_key(MOTION_SENSOR_X_KEY, buffer, 2);
441 		break;
442 	case SENSOR_Y:
443 		ret = applesmc_read_key(MOTION_SENSOR_Y_KEY, buffer, 2);
444 		break;
445 	case SENSOR_Z:
446 		ret = applesmc_read_key(MOTION_SENSOR_Z_KEY, buffer, 2);
447 		break;
448 	default:
449 		ret = -EINVAL;
450 	}
451 
452 	*value = ((s16)buffer[0] << 8) | buffer[1];
453 
454 	return ret;
455 }
456 
457 /*
458  * applesmc_device_init - initialize the accelerometer.  Can sleep.
459  */
460 static void applesmc_device_init(void)
461 {
462 	int total;
463 	u8 buffer[2];
464 
465 	if (!smcreg.has_accelerometer)
466 		return;
467 
468 	for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
469 		if (!applesmc_read_key(MOTION_SENSOR_KEY, buffer, 2) &&
470 				(buffer[0] != 0x00 || buffer[1] != 0x00))
471 			return;
472 		buffer[0] = 0xe0;
473 		buffer[1] = 0x00;
474 		applesmc_write_key(MOTION_SENSOR_KEY, buffer, 2);
475 		msleep(INIT_WAIT_MSECS);
476 	}
477 
478 	pr_warn("failed to init the device\n");
479 }
480 
481 /*
482  * applesmc_init_smcreg_try - Try to initialize register cache. Idempotent.
483  */
484 static int applesmc_init_smcreg_try(void)
485 {
486 	struct applesmc_registers *s = &smcreg;
487 	bool left_light_sensor, right_light_sensor;
488 	u8 tmp[1];
489 	int ret;
490 
491 	if (s->init_complete)
492 		return 0;
493 
494 	ret = read_register_count(&s->key_count);
495 	if (ret)
496 		return ret;
497 
498 	if (!s->cache)
499 		s->cache = kcalloc(s->key_count, sizeof(*s->cache), GFP_KERNEL);
500 	if (!s->cache)
501 		return -ENOMEM;
502 
503 	ret = applesmc_read_key(FANS_COUNT, tmp, 1);
504 	if (ret)
505 		return ret;
506 	s->fan_count = tmp[0];
507 
508 	ret = applesmc_get_lower_bound(&s->temp_begin, "T");
509 	if (ret)
510 		return ret;
511 	ret = applesmc_get_lower_bound(&s->temp_end, "U");
512 	if (ret)
513 		return ret;
514 	s->temp_count = s->temp_end - s->temp_begin;
515 
516 	ret = applesmc_has_key(LIGHT_SENSOR_LEFT_KEY, &left_light_sensor);
517 	if (ret)
518 		return ret;
519 	ret = applesmc_has_key(LIGHT_SENSOR_RIGHT_KEY, &right_light_sensor);
520 	if (ret)
521 		return ret;
522 	ret = applesmc_has_key(MOTION_SENSOR_KEY, &s->has_accelerometer);
523 	if (ret)
524 		return ret;
525 	ret = applesmc_has_key(BACKLIGHT_KEY, &s->has_key_backlight);
526 	if (ret)
527 		return ret;
528 
529 	s->num_light_sensors = left_light_sensor + right_light_sensor;
530 	s->init_complete = true;
531 
532 	pr_info("key=%d fan=%d temp=%d acc=%d lux=%d kbd=%d\n",
533 	       s->key_count, s->fan_count, s->temp_count,
534 	       s->has_accelerometer,
535 	       s->num_light_sensors,
536 	       s->has_key_backlight);
537 
538 	return 0;
539 }
540 
541 /*
542  * applesmc_init_smcreg - Initialize register cache.
543  *
544  * Retries until initialization is successful, or the operation times out.
545  *
546  */
547 static int applesmc_init_smcreg(void)
548 {
549 	int ms, ret;
550 
551 	for (ms = 0; ms < INIT_TIMEOUT_MSECS; ms += INIT_WAIT_MSECS) {
552 		ret = applesmc_init_smcreg_try();
553 		if (!ret) {
554 			if (ms)
555 				pr_info("init_smcreg() took %d ms\n", ms);
556 			return 0;
557 		}
558 		msleep(INIT_WAIT_MSECS);
559 	}
560 
561 	kfree(smcreg.cache);
562 	smcreg.cache = NULL;
563 
564 	return ret;
565 }
566 
567 static void applesmc_destroy_smcreg(void)
568 {
569 	kfree(smcreg.cache);
570 	smcreg.cache = NULL;
571 	smcreg.init_complete = false;
572 }
573 
574 /* Device model stuff */
575 static int applesmc_probe(struct platform_device *dev)
576 {
577 	int ret;
578 
579 	ret = applesmc_init_smcreg();
580 	if (ret)
581 		return ret;
582 
583 	applesmc_device_init();
584 
585 	return 0;
586 }
587 
588 /* Synchronize device with memorized backlight state */
589 static int applesmc_pm_resume(struct device *dev)
590 {
591 	if (smcreg.has_key_backlight)
592 		applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
593 	return 0;
594 }
595 
596 /* Reinitialize device on resume from hibernation */
597 static int applesmc_pm_restore(struct device *dev)
598 {
599 	applesmc_device_init();
600 	return applesmc_pm_resume(dev);
601 }
602 
603 static const struct dev_pm_ops applesmc_pm_ops = {
604 	.resume = applesmc_pm_resume,
605 	.restore = applesmc_pm_restore,
606 };
607 
608 static struct platform_driver applesmc_driver = {
609 	.probe = applesmc_probe,
610 	.driver	= {
611 		.name = "applesmc",
612 		.owner = THIS_MODULE,
613 		.pm = &applesmc_pm_ops,
614 	},
615 };
616 
617 /*
618  * applesmc_calibrate - Set our "resting" values.  Callers must
619  * hold applesmc_lock.
620  */
621 static void applesmc_calibrate(void)
622 {
623 	applesmc_read_motion_sensor(SENSOR_X, &rest_x);
624 	applesmc_read_motion_sensor(SENSOR_Y, &rest_y);
625 	rest_x = -rest_x;
626 }
627 
628 static void applesmc_idev_poll(struct input_polled_dev *dev)
629 {
630 	struct input_dev *idev = dev->input;
631 	s16 x, y;
632 
633 	if (applesmc_read_motion_sensor(SENSOR_X, &x))
634 		return;
635 	if (applesmc_read_motion_sensor(SENSOR_Y, &y))
636 		return;
637 
638 	x = -x;
639 	input_report_abs(idev, ABS_X, x - rest_x);
640 	input_report_abs(idev, ABS_Y, y - rest_y);
641 	input_sync(idev);
642 }
643 
644 /* Sysfs Files */
645 
646 static ssize_t applesmc_name_show(struct device *dev,
647 				   struct device_attribute *attr, char *buf)
648 {
649 	return snprintf(buf, PAGE_SIZE, "applesmc\n");
650 }
651 
652 static ssize_t applesmc_position_show(struct device *dev,
653 				   struct device_attribute *attr, char *buf)
654 {
655 	int ret;
656 	s16 x, y, z;
657 
658 	ret = applesmc_read_motion_sensor(SENSOR_X, &x);
659 	if (ret)
660 		goto out;
661 	ret = applesmc_read_motion_sensor(SENSOR_Y, &y);
662 	if (ret)
663 		goto out;
664 	ret = applesmc_read_motion_sensor(SENSOR_Z, &z);
665 	if (ret)
666 		goto out;
667 
668 out:
669 	if (ret)
670 		return ret;
671 	else
672 		return snprintf(buf, PAGE_SIZE, "(%d,%d,%d)\n", x, y, z);
673 }
674 
675 static ssize_t applesmc_light_show(struct device *dev,
676 				struct device_attribute *attr, char *sysfsbuf)
677 {
678 	const struct applesmc_entry *entry;
679 	static int data_length;
680 	int ret;
681 	u8 left = 0, right = 0;
682 	u8 buffer[10];
683 
684 	if (!data_length) {
685 		entry = applesmc_get_entry_by_key(LIGHT_SENSOR_LEFT_KEY);
686 		if (IS_ERR(entry))
687 			return PTR_ERR(entry);
688 		if (entry->len > 10)
689 			return -ENXIO;
690 		data_length = entry->len;
691 		pr_info("light sensor data length set to %d\n", data_length);
692 	}
693 
694 	ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, buffer, data_length);
695 	/* newer macbooks report a single 10-bit bigendian value */
696 	if (data_length == 10) {
697 		left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2;
698 		goto out;
699 	}
700 	left = buffer[2];
701 	if (ret)
702 		goto out;
703 	ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length);
704 	right = buffer[2];
705 
706 out:
707 	if (ret)
708 		return ret;
709 	else
710 		return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", left, right);
711 }
712 
713 /* Displays sensor key as label */
714 static ssize_t applesmc_show_sensor_label(struct device *dev,
715 			struct device_attribute *devattr, char *sysfsbuf)
716 {
717 	int index = smcreg.temp_begin + to_index(devattr);
718 	const struct applesmc_entry *entry;
719 
720 	entry = applesmc_get_entry_by_index(index);
721 	if (IS_ERR(entry))
722 		return PTR_ERR(entry);
723 
724 	return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
725 }
726 
727 /* Displays degree Celsius * 1000 */
728 static ssize_t applesmc_show_temperature(struct device *dev,
729 			struct device_attribute *devattr, char *sysfsbuf)
730 {
731 	int index = smcreg.temp_begin + to_index(devattr);
732 	const struct applesmc_entry *entry;
733 	int ret;
734 	u8 buffer[2];
735 	unsigned int temp;
736 
737 	entry = applesmc_get_entry_by_index(index);
738 	if (IS_ERR(entry))
739 		return PTR_ERR(entry);
740 	if (entry->len > 2)
741 		return -EINVAL;
742 
743 	ret = applesmc_read_entry(entry, buffer, entry->len);
744 	if (ret)
745 		return ret;
746 
747 	if (entry->len == 2) {
748 		temp = buffer[0] * 1000;
749 		temp += (buffer[1] >> 6) * 250;
750 	} else {
751 		temp = buffer[0] * 4000;
752 	}
753 
754 	return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", temp);
755 }
756 
757 static ssize_t applesmc_show_fan_speed(struct device *dev,
758 				struct device_attribute *attr, char *sysfsbuf)
759 {
760 	int ret;
761 	unsigned int speed = 0;
762 	char newkey[5];
763 	u8 buffer[2];
764 
765 	sprintf(newkey, fan_speed_fmt[to_option(attr)], to_index(attr));
766 
767 	ret = applesmc_read_key(newkey, buffer, 2);
768 	speed = ((buffer[0] << 8 | buffer[1]) >> 2);
769 
770 	if (ret)
771 		return ret;
772 	else
773 		return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
774 }
775 
776 static ssize_t applesmc_store_fan_speed(struct device *dev,
777 					struct device_attribute *attr,
778 					const char *sysfsbuf, size_t count)
779 {
780 	int ret;
781 	unsigned long speed;
782 	char newkey[5];
783 	u8 buffer[2];
784 
785 	if (strict_strtoul(sysfsbuf, 10, &speed) < 0 || speed >= 0x4000)
786 		return -EINVAL;		/* Bigger than a 14-bit value */
787 
788 	sprintf(newkey, fan_speed_fmt[to_option(attr)], to_index(attr));
789 
790 	buffer[0] = (speed >> 6) & 0xff;
791 	buffer[1] = (speed << 2) & 0xff;
792 	ret = applesmc_write_key(newkey, buffer, 2);
793 
794 	if (ret)
795 		return ret;
796 	else
797 		return count;
798 }
799 
800 static ssize_t applesmc_show_fan_manual(struct device *dev,
801 			struct device_attribute *attr, char *sysfsbuf)
802 {
803 	int ret;
804 	u16 manual = 0;
805 	u8 buffer[2];
806 
807 	ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
808 	manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01;
809 
810 	if (ret)
811 		return ret;
812 	else
813 		return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
814 }
815 
816 static ssize_t applesmc_store_fan_manual(struct device *dev,
817 					 struct device_attribute *attr,
818 					 const char *sysfsbuf, size_t count)
819 {
820 	int ret;
821 	u8 buffer[2];
822 	unsigned long input;
823 	u16 val;
824 
825 	if (strict_strtoul(sysfsbuf, 10, &input) < 0)
826 		return -EINVAL;
827 
828 	ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
829 	val = (buffer[0] << 8 | buffer[1]);
830 	if (ret)
831 		goto out;
832 
833 	if (input)
834 		val = val | (0x01 << to_index(attr));
835 	else
836 		val = val & ~(0x01 << to_index(attr));
837 
838 	buffer[0] = (val >> 8) & 0xFF;
839 	buffer[1] = val & 0xFF;
840 
841 	ret = applesmc_write_key(FANS_MANUAL, buffer, 2);
842 
843 out:
844 	if (ret)
845 		return ret;
846 	else
847 		return count;
848 }
849 
850 static ssize_t applesmc_show_fan_position(struct device *dev,
851 				struct device_attribute *attr, char *sysfsbuf)
852 {
853 	int ret;
854 	char newkey[5];
855 	u8 buffer[17];
856 
857 	sprintf(newkey, FAN_ID_FMT, to_index(attr));
858 
859 	ret = applesmc_read_key(newkey, buffer, 16);
860 	buffer[16] = 0;
861 
862 	if (ret)
863 		return ret;
864 	else
865 		return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", buffer+4);
866 }
867 
868 static ssize_t applesmc_calibrate_show(struct device *dev,
869 				struct device_attribute *attr, char *sysfsbuf)
870 {
871 	return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", rest_x, rest_y);
872 }
873 
874 static ssize_t applesmc_calibrate_store(struct device *dev,
875 	struct device_attribute *attr, const char *sysfsbuf, size_t count)
876 {
877 	applesmc_calibrate();
878 
879 	return count;
880 }
881 
882 static void applesmc_backlight_set(struct work_struct *work)
883 {
884 	applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
885 }
886 static DECLARE_WORK(backlight_work, &applesmc_backlight_set);
887 
888 static void applesmc_brightness_set(struct led_classdev *led_cdev,
889 						enum led_brightness value)
890 {
891 	int ret;
892 
893 	backlight_state[0] = value;
894 	ret = queue_work(applesmc_led_wq, &backlight_work);
895 
896 	if (debug && (!ret))
897 		printk(KERN_DEBUG "applesmc: work was already on the queue.\n");
898 }
899 
900 static ssize_t applesmc_key_count_show(struct device *dev,
901 				struct device_attribute *attr, char *sysfsbuf)
902 {
903 	int ret;
904 	u8 buffer[4];
905 	u32 count;
906 
907 	ret = applesmc_read_key(KEY_COUNT_KEY, buffer, 4);
908 	count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
909 						((u32)buffer[2]<<8) + buffer[3];
910 
911 	if (ret)
912 		return ret;
913 	else
914 		return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
915 }
916 
917 static ssize_t applesmc_key_at_index_read_show(struct device *dev,
918 				struct device_attribute *attr, char *sysfsbuf)
919 {
920 	const struct applesmc_entry *entry;
921 	int ret;
922 
923 	entry = applesmc_get_entry_by_index(key_at_index);
924 	if (IS_ERR(entry))
925 		return PTR_ERR(entry);
926 	ret = applesmc_read_entry(entry, sysfsbuf, entry->len);
927 	if (ret)
928 		return ret;
929 
930 	return entry->len;
931 }
932 
933 static ssize_t applesmc_key_at_index_data_length_show(struct device *dev,
934 				struct device_attribute *attr, char *sysfsbuf)
935 {
936 	const struct applesmc_entry *entry;
937 
938 	entry = applesmc_get_entry_by_index(key_at_index);
939 	if (IS_ERR(entry))
940 		return PTR_ERR(entry);
941 
942 	return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", entry->len);
943 }
944 
945 static ssize_t applesmc_key_at_index_type_show(struct device *dev,
946 				struct device_attribute *attr, char *sysfsbuf)
947 {
948 	const struct applesmc_entry *entry;
949 
950 	entry = applesmc_get_entry_by_index(key_at_index);
951 	if (IS_ERR(entry))
952 		return PTR_ERR(entry);
953 
954 	return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->type);
955 }
956 
957 static ssize_t applesmc_key_at_index_name_show(struct device *dev,
958 				struct device_attribute *attr, char *sysfsbuf)
959 {
960 	const struct applesmc_entry *entry;
961 
962 	entry = applesmc_get_entry_by_index(key_at_index);
963 	if (IS_ERR(entry))
964 		return PTR_ERR(entry);
965 
966 	return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
967 }
968 
969 static ssize_t applesmc_key_at_index_show(struct device *dev,
970 				struct device_attribute *attr, char *sysfsbuf)
971 {
972 	return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", key_at_index);
973 }
974 
975 static ssize_t applesmc_key_at_index_store(struct device *dev,
976 	struct device_attribute *attr, const char *sysfsbuf, size_t count)
977 {
978 	unsigned long newkey;
979 
980 	if (strict_strtoul(sysfsbuf, 10, &newkey) < 0
981 	    || newkey >= smcreg.key_count)
982 		return -EINVAL;
983 
984 	key_at_index = newkey;
985 	return count;
986 }
987 
988 static struct led_classdev applesmc_backlight = {
989 	.name			= "smc::kbd_backlight",
990 	.default_trigger	= "nand-disk",
991 	.brightness_set		= applesmc_brightness_set,
992 };
993 
994 static struct applesmc_node_group info_group[] = {
995 	{ "name", applesmc_name_show },
996 	{ "key_count", applesmc_key_count_show },
997 	{ "key_at_index", applesmc_key_at_index_show, applesmc_key_at_index_store },
998 	{ "key_at_index_name", applesmc_key_at_index_name_show },
999 	{ "key_at_index_type", applesmc_key_at_index_type_show },
1000 	{ "key_at_index_data_length", applesmc_key_at_index_data_length_show },
1001 	{ "key_at_index_data", applesmc_key_at_index_read_show },
1002 	{ }
1003 };
1004 
1005 static struct applesmc_node_group accelerometer_group[] = {
1006 	{ "position", applesmc_position_show },
1007 	{ "calibrate", applesmc_calibrate_show, applesmc_calibrate_store },
1008 	{ }
1009 };
1010 
1011 static struct applesmc_node_group light_sensor_group[] = {
1012 	{ "light", applesmc_light_show },
1013 	{ }
1014 };
1015 
1016 static struct applesmc_node_group fan_group[] = {
1017 	{ "fan%d_label", applesmc_show_fan_position },
1018 	{ "fan%d_input", applesmc_show_fan_speed, NULL, 0 },
1019 	{ "fan%d_min", applesmc_show_fan_speed, applesmc_store_fan_speed, 1 },
1020 	{ "fan%d_max", applesmc_show_fan_speed, NULL, 2 },
1021 	{ "fan%d_safe", applesmc_show_fan_speed, NULL, 3 },
1022 	{ "fan%d_output", applesmc_show_fan_speed, applesmc_store_fan_speed, 4 },
1023 	{ "fan%d_manual", applesmc_show_fan_manual, applesmc_store_fan_manual },
1024 	{ }
1025 };
1026 
1027 static struct applesmc_node_group temp_group[] = {
1028 	{ "temp%d_label", applesmc_show_sensor_label },
1029 	{ "temp%d_input", applesmc_show_temperature },
1030 	{ }
1031 };
1032 
1033 /* Module stuff */
1034 
1035 /*
1036  * applesmc_destroy_nodes - remove files and free associated memory
1037  */
1038 static void applesmc_destroy_nodes(struct applesmc_node_group *groups)
1039 {
1040 	struct applesmc_node_group *grp;
1041 	struct applesmc_dev_attr *node;
1042 
1043 	for (grp = groups; grp->nodes; grp++) {
1044 		for (node = grp->nodes; node->sda.dev_attr.attr.name; node++)
1045 			sysfs_remove_file(&pdev->dev.kobj,
1046 					  &node->sda.dev_attr.attr);
1047 		kfree(grp->nodes);
1048 		grp->nodes = NULL;
1049 	}
1050 }
1051 
1052 /*
1053  * applesmc_create_nodes - create a two-dimensional group of sysfs files
1054  */
1055 static int applesmc_create_nodes(struct applesmc_node_group *groups, int num)
1056 {
1057 	struct applesmc_node_group *grp;
1058 	struct applesmc_dev_attr *node;
1059 	struct attribute *attr;
1060 	int ret, i;
1061 
1062 	for (grp = groups; grp->format; grp++) {
1063 		grp->nodes = kcalloc(num + 1, sizeof(*node), GFP_KERNEL);
1064 		if (!grp->nodes) {
1065 			ret = -ENOMEM;
1066 			goto out;
1067 		}
1068 		for (i = 0; i < num; i++) {
1069 			node = &grp->nodes[i];
1070 			sprintf(node->name, grp->format, i + 1);
1071 			node->sda.index = (grp->option << 16) | (i & 0xffff);
1072 			node->sda.dev_attr.show = grp->show;
1073 			node->sda.dev_attr.store = grp->store;
1074 			attr = &node->sda.dev_attr.attr;
1075 			sysfs_attr_init(attr);
1076 			attr->name = node->name;
1077 			attr->mode = S_IRUGO | (grp->store ? S_IWUSR : 0);
1078 			ret = sysfs_create_file(&pdev->dev.kobj, attr);
1079 			if (ret) {
1080 				attr->name = NULL;
1081 				goto out;
1082 			}
1083 		}
1084 	}
1085 
1086 	return 0;
1087 out:
1088 	applesmc_destroy_nodes(groups);
1089 	return ret;
1090 }
1091 
1092 /* Create accelerometer ressources */
1093 static int applesmc_create_accelerometer(void)
1094 {
1095 	struct input_dev *idev;
1096 	int ret;
1097 
1098 	if (!smcreg.has_accelerometer)
1099 		return 0;
1100 
1101 	ret = applesmc_create_nodes(accelerometer_group, 1);
1102 	if (ret)
1103 		goto out;
1104 
1105 	applesmc_idev = input_allocate_polled_device();
1106 	if (!applesmc_idev) {
1107 		ret = -ENOMEM;
1108 		goto out_sysfs;
1109 	}
1110 
1111 	applesmc_idev->poll = applesmc_idev_poll;
1112 	applesmc_idev->poll_interval = APPLESMC_POLL_INTERVAL;
1113 
1114 	/* initial calibrate for the input device */
1115 	applesmc_calibrate();
1116 
1117 	/* initialize the input device */
1118 	idev = applesmc_idev->input;
1119 	idev->name = "applesmc";
1120 	idev->id.bustype = BUS_HOST;
1121 	idev->dev.parent = &pdev->dev;
1122 	idev->evbit[0] = BIT_MASK(EV_ABS);
1123 	input_set_abs_params(idev, ABS_X,
1124 			-256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
1125 	input_set_abs_params(idev, ABS_Y,
1126 			-256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
1127 
1128 	ret = input_register_polled_device(applesmc_idev);
1129 	if (ret)
1130 		goto out_idev;
1131 
1132 	return 0;
1133 
1134 out_idev:
1135 	input_free_polled_device(applesmc_idev);
1136 
1137 out_sysfs:
1138 	applesmc_destroy_nodes(accelerometer_group);
1139 
1140 out:
1141 	pr_warn("driver init failed (ret=%d)!\n", ret);
1142 	return ret;
1143 }
1144 
1145 /* Release all ressources used by the accelerometer */
1146 static void applesmc_release_accelerometer(void)
1147 {
1148 	if (!smcreg.has_accelerometer)
1149 		return;
1150 	input_unregister_polled_device(applesmc_idev);
1151 	input_free_polled_device(applesmc_idev);
1152 	applesmc_destroy_nodes(accelerometer_group);
1153 }
1154 
1155 static int applesmc_create_light_sensor(void)
1156 {
1157 	if (!smcreg.num_light_sensors)
1158 		return 0;
1159 	return applesmc_create_nodes(light_sensor_group, 1);
1160 }
1161 
1162 static void applesmc_release_light_sensor(void)
1163 {
1164 	if (!smcreg.num_light_sensors)
1165 		return;
1166 	applesmc_destroy_nodes(light_sensor_group);
1167 }
1168 
1169 static int applesmc_create_key_backlight(void)
1170 {
1171 	if (!smcreg.has_key_backlight)
1172 		return 0;
1173 	applesmc_led_wq = create_singlethread_workqueue("applesmc-led");
1174 	if (!applesmc_led_wq)
1175 		return -ENOMEM;
1176 	return led_classdev_register(&pdev->dev, &applesmc_backlight);
1177 }
1178 
1179 static void applesmc_release_key_backlight(void)
1180 {
1181 	if (!smcreg.has_key_backlight)
1182 		return;
1183 	led_classdev_unregister(&applesmc_backlight);
1184 	destroy_workqueue(applesmc_led_wq);
1185 }
1186 
1187 static int applesmc_dmi_match(const struct dmi_system_id *id)
1188 {
1189 	return 1;
1190 }
1191 
1192 /* Note that DMI_MATCH(...,"MacBook") will match "MacBookPro1,1".
1193  * So we need to put "Apple MacBook Pro" before "Apple MacBook". */
1194 static __initdata struct dmi_system_id applesmc_whitelist[] = {
1195 	{ applesmc_dmi_match, "Apple MacBook Air", {
1196 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1197 	  DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir") },
1198 	},
1199 	{ applesmc_dmi_match, "Apple MacBook Pro", {
1200 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1201 	  DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro") },
1202 	},
1203 	{ applesmc_dmi_match, "Apple MacBook", {
1204 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1205 	  DMI_MATCH(DMI_PRODUCT_NAME, "MacBook") },
1206 	},
1207 	{ applesmc_dmi_match, "Apple Macmini", {
1208 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1209 	  DMI_MATCH(DMI_PRODUCT_NAME, "Macmini") },
1210 	},
1211 	{ applesmc_dmi_match, "Apple MacPro", {
1212 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1213 	  DMI_MATCH(DMI_PRODUCT_NAME, "MacPro") },
1214 	},
1215 	{ applesmc_dmi_match, "Apple iMac", {
1216 	  DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
1217 	  DMI_MATCH(DMI_PRODUCT_NAME, "iMac") },
1218 	},
1219 	{ .ident = NULL }
1220 };
1221 
1222 static int __init applesmc_init(void)
1223 {
1224 	int ret;
1225 
1226 	if (!dmi_check_system(applesmc_whitelist)) {
1227 		pr_warn("supported laptop not found!\n");
1228 		ret = -ENODEV;
1229 		goto out;
1230 	}
1231 
1232 	if (!request_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS,
1233 								"applesmc")) {
1234 		ret = -ENXIO;
1235 		goto out;
1236 	}
1237 
1238 	ret = platform_driver_register(&applesmc_driver);
1239 	if (ret)
1240 		goto out_region;
1241 
1242 	pdev = platform_device_register_simple("applesmc", APPLESMC_DATA_PORT,
1243 					       NULL, 0);
1244 	if (IS_ERR(pdev)) {
1245 		ret = PTR_ERR(pdev);
1246 		goto out_driver;
1247 	}
1248 
1249 	/* create register cache */
1250 	ret = applesmc_init_smcreg();
1251 	if (ret)
1252 		goto out_device;
1253 
1254 	ret = applesmc_create_nodes(info_group, 1);
1255 	if (ret)
1256 		goto out_smcreg;
1257 
1258 	ret = applesmc_create_nodes(fan_group, smcreg.fan_count);
1259 	if (ret)
1260 		goto out_info;
1261 
1262 	ret = applesmc_create_nodes(temp_group, smcreg.temp_count);
1263 	if (ret)
1264 		goto out_fans;
1265 
1266 	ret = applesmc_create_accelerometer();
1267 	if (ret)
1268 		goto out_temperature;
1269 
1270 	ret = applesmc_create_light_sensor();
1271 	if (ret)
1272 		goto out_accelerometer;
1273 
1274 	ret = applesmc_create_key_backlight();
1275 	if (ret)
1276 		goto out_light_sysfs;
1277 
1278 	hwmon_dev = hwmon_device_register(&pdev->dev);
1279 	if (IS_ERR(hwmon_dev)) {
1280 		ret = PTR_ERR(hwmon_dev);
1281 		goto out_light_ledclass;
1282 	}
1283 
1284 	return 0;
1285 
1286 out_light_ledclass:
1287 	applesmc_release_key_backlight();
1288 out_light_sysfs:
1289 	applesmc_release_light_sensor();
1290 out_accelerometer:
1291 	applesmc_release_accelerometer();
1292 out_temperature:
1293 	applesmc_destroy_nodes(temp_group);
1294 out_fans:
1295 	applesmc_destroy_nodes(fan_group);
1296 out_info:
1297 	applesmc_destroy_nodes(info_group);
1298 out_smcreg:
1299 	applesmc_destroy_smcreg();
1300 out_device:
1301 	platform_device_unregister(pdev);
1302 out_driver:
1303 	platform_driver_unregister(&applesmc_driver);
1304 out_region:
1305 	release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
1306 out:
1307 	pr_warn("driver init failed (ret=%d)!\n", ret);
1308 	return ret;
1309 }
1310 
1311 static void __exit applesmc_exit(void)
1312 {
1313 	hwmon_device_unregister(hwmon_dev);
1314 	applesmc_release_key_backlight();
1315 	applesmc_release_light_sensor();
1316 	applesmc_release_accelerometer();
1317 	applesmc_destroy_nodes(temp_group);
1318 	applesmc_destroy_nodes(fan_group);
1319 	applesmc_destroy_nodes(info_group);
1320 	applesmc_destroy_smcreg();
1321 	platform_device_unregister(pdev);
1322 	platform_driver_unregister(&applesmc_driver);
1323 	release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
1324 }
1325 
1326 module_init(applesmc_init);
1327 module_exit(applesmc_exit);
1328 
1329 MODULE_AUTHOR("Nicolas Boichat");
1330 MODULE_DESCRIPTION("Apple SMC");
1331 MODULE_LICENSE("GPL v2");
1332 MODULE_DEVICE_TABLE(dmi, applesmc_whitelist);
1333