summaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/hdaps.c
blob: 4c56411f399316c8bb11833beda296a351c34537 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
/*
 * drivers/hwmon/hdaps.c - driver for IBM's Hard Drive Active Protection System
 *
 * Copyright (C) 2005 Robert Love <rml@novell.com>
 * Copyright (C) 2005 Jesper Juhl <jesper.juhl@gmail.com>
 *
 * The HardDisk Active Protection System (hdaps) is present in the IBM ThinkPad
 * T41, T42, T43, R50, R50p, R51, and X40, at least.  It provides a basic
 * two-axis accelerometer and other data, such as the device's temperature.
 *
 * This driver is based on the document by Mark A. Smith available at
 * http://www.almaden.ibm.com/cs/people/marksmith/tpaps.html and a lot of trial
 * and error.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License v2 as published by the
 * Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#include <linux/delay.h>
#include <linux/device.h>
#include <linux/input.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/timer.h>
#include <linux/dmi.h>
#include <asm/io.h>

#define HDAPS_LOW_PORT		0x1600	/* first port used by hdaps */
#define HDAPS_NR_PORTS		0x30	/* number of ports: 0x1600 - 0x162f */

#define HDAPS_PORT_STATE	0x1611	/* device state */
#define HDAPS_PORT_YPOS		0x1612	/* y-axis position */
#define	HDAPS_PORT_XPOS		0x1614	/* x-axis position */
#define HDAPS_PORT_TEMP1	0x1616	/* device temperature, in celcius */
#define HDAPS_PORT_YVAR		0x1617	/* y-axis variance (what is this?) */
#define HDAPS_PORT_XVAR		0x1619	/* x-axis variance (what is this?) */
#define HDAPS_PORT_TEMP2	0x161b	/* device temperature (again?) */
#define HDAPS_PORT_UNKNOWN	0x161c	/* what is this? */
#define HDAPS_PORT_KMACT	0x161d	/* keyboard or mouse activity */

#define STATE_FRESH		0x50	/* accelerometer data is fresh */

#define KEYBD_MASK		0x20	/* set if keyboard activity */
#define MOUSE_MASK		0x40	/* set if mouse activity */
#define KEYBD_ISSET(n)		(!! (n & KEYBD_MASK))	/* keyboard used? */
#define MOUSE_ISSET(n)		(!! (n & MOUSE_MASK))	/* mouse used? */

#define INIT_TIMEOUT_MSECS	4000	/* wait up to 4s for device init ... */
#define INIT_WAIT_MSECS		200	/* ... in 200ms increments */

#define HDAPS_POLL_PERIOD	(HZ/20)	/* poll for input every 1/20s */
#define HDAPS_INPUT_FUZZ	4	/* input event threshold */

static struct timer_list hdaps_timer;
static struct platform_device *pdev;
static unsigned int hdaps_invert;
static u8 km_activity;
static int rest_x;
static int rest_y;

static DECLARE_MUTEX(hdaps_sem);

/*
 * __get_latch - Get the value from a given port.  Callers must hold hdaps_sem.
 */
static inline u8 __get_latch(u16 port)
{
	return inb(port) & 0xff;
}

/*
 * __check_latch - Check a port latch for a given value.  Returns zero if the
 * port contains the given value.  Callers must hold hdaps_sem.
 */
static inline int __check_latch(u16 port, u8 val)
{
	if (__get_latch(port) == val)
		return 0;
	return -EINVAL;
}

/*
 * __wait_latch - Wait up to 100us for a port latch to get a certain value,
 * returning zero if the value is obtained.  Callers must hold hdaps_sem.
 */
static int __wait_latch(u16 port, u8 val)
{
	unsigned int i;

	for (i = 0; i < 20; i++) {
		if (!__check_latch(port, val))
			return 0;
		udelay(5);
	}

	return -EIO;
}

/*
 * __device_refresh - request a refresh from the accelerometer.  Does not wait
 * for refresh to complete.  Callers must hold hdaps_sem.
 */
static void __device_refresh(void)
{
	udelay(200);
	if (inb(0x1604) != STATE_FRESH) {
		outb(0x11, 0x1610);
		outb(0x01, 0x161f);
	}
}

/*
 * __device_refresh_sync - request a synchronous refresh from the
 * accelerometer.  We wait for the refresh to complete.  Returns zero if
 * successful and nonzero on error.  Callers must hold hdaps_sem.
 */
static int __device_refresh_sync(void)
{
	__device_refresh();
	return __wait_latch(0x1604, STATE_FRESH);
}

/*
 * __device_complete - indicate to the accelerometer that we are done reading
 * data, and then initiate an async refresh.  Callers must hold hdaps_sem.
 */
static inline void __device_complete(void)
{
	inb(0x161f);
	inb(0x1604);
	__device_refresh();
}

/*
 * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
 * the given pointer.  Returns zero on success or a negative error on failure.
 * Can sleep.
 */
static int hdaps_readb_one(unsigned int port, u8 *val)
{
	int ret;

	down(&hdaps_sem);

	/* do a sync refresh -- we need to be sure that we read fresh data */
	ret = __device_refresh_sync();
	if (ret)
		goto out;

	*val = inb(port);
	__device_complete();

out:
	up(&hdaps_sem);
	return ret;
}

/* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
			     int *x, int *y)
{
	/* do a sync refresh -- we need to be sure that we read fresh data */
	if (__device_refresh_sync())
		return -EIO;

	*y = inw(port2);
	*x = inw(port1);
	km_activity = inb(HDAPS_PORT_KMACT);
	__device_complete();

	/* if hdaps_invert is set, negate the two values */
	if (hdaps_invert) {
		*x = -*x;
		*y = -*y;
	}

	return 0;
}

/*
 * hdaps_read_pair - reads the values from a pair of ports, placing the values
 * in the given pointers.  Returns zero on success.  Can sleep.
 */
static int hdaps_read_pair(unsigned int port1, unsigned int port2,
			   int *val1, int *val2)
{
	int ret;

	down(&hdaps_sem);
	ret = __hdaps_read_pair(port1, port2, val1, val2);
	up(&hdaps_sem);

	return ret;
}

/*
 * hdaps_device_init - initialize the accelerometer.  Returns zero on success
 * and negative error code on failure.  Can sleep.
 */
static int hdaps_device_init(void)
{
	int total, ret = -ENXIO;

	down(&hdaps_sem);

	outb(0x13, 0x1610);
	outb(0x01, 0x161f);
	if (__wait_latch(0x161f, 0x00))
		goto out;

	/*
	 * Most ThinkPads return 0x01.
	 *
	 * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
	 * have "inverted" axises.
	 *
	 * The 0x02 value occurs when the chip has been previously initialized.
	 */
	if (__check_latch(0x1611, 0x03) &&
		     __check_latch(0x1611, 0x02) &&
		     __check_latch(0x1611, 0x01))
		goto out;

	printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
	       __get_latch(0x1611));

	outb(0x17, 0x1610);
	outb(0x81, 0x1611);
	outb(0x01, 0x161f);
	if (__wait_latch(0x161f, 0x00))
		goto out;
	if (__wait_latch(0x1611, 0x00))
		goto out;
	if (__wait_latch(0x1612, 0x60))
		goto out;
	if (__wait_latch(0x1613, 0x00))
		goto out;
	outb(0x14, 0x1610);
	outb(0x01, 0x1611);
	outb(0x01, 0x161f);
	if (__wait_latch(0x161f, 0x00))
		goto out;
	outb(0x10, 0x1610);
	outb(0xc8, 0x1611);
	outb(0x00, 0x1612);
	outb(0x02, 0x1613);
	outb(0x01, 0x161f);
	if (__wait_latch(0x161f, 0x00))
		goto out;
	if (__device_refresh_sync())
		goto out;
	if (__wait_latch(0x1611, 0x00))
		goto out;

	/* we have done our dance, now let's wait for the applause */
	for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
		int x, y;

		/* a read of the device helps push it into action */
		__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
		if (!__wait_latch(0x1611, 0x02)) {
			ret = 0;
			break;
		}

		msleep(INIT_WAIT_MSECS);
	}

out:
	up(&hdaps_sem);
	return ret;
}


/* Device model stuff */

static int hdaps_probe(struct device *dev)
{
	int ret;

	ret = hdaps_device_init();
	if (ret)
		return ret;

	printk(KERN_INFO "hdaps: device successfully initialized.\n");
	return 0;
}

static int hdaps_resume(struct device *dev, u32 level)
{
	if (level == RESUME_ENABLE)
		return hdaps_device_init();
	return 0;
}

static struct device_driver hdaps_driver = {
	.name = "hdaps",
	.bus = &platform_bus_type,
	.owner = THIS_MODULE,
	.probe = hdaps_probe,
	.resume = hdaps_resume
};

/* Input class stuff */

static struct input_dev hdaps_idev = {
	.name = "hdaps",
	.evbit = { BIT(EV_ABS) },
	.absbit = { BIT(ABS_X) | BIT(ABS_Y) },
	.absmin  = { [ABS_X] = -256, [ABS_Y] = -256 },
	.absmax  = { [ABS_X] = 256, [ABS_Y] = 256 },
	.absfuzz = { [ABS_X] = HDAPS_INPUT_FUZZ, [ABS_Y] = HDAPS_INPUT_FUZZ },
	.absflat = { [ABS_X] = HDAPS_INPUT_FUZZ, [ABS_Y] = HDAPS_INPUT_FUZZ },
};

/*
 * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_sem.
 */
static void hdaps_calibrate(void)
{
	__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
}

static void hdaps_mousedev_poll(unsigned long unused)
{
	int x, y;

	/* Cannot sleep.  Try nonblockingly.  If we fail, try again later. */
	if (down_trylock(&hdaps_sem)) {
		mod_timer(&hdaps_timer,jiffies + HDAPS_POLL_PERIOD);
		return;
	}

	if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
		goto out;

	input_report_abs(&hdaps_idev, ABS_X, x - rest_x);
	input_report_abs(&hdaps_idev, ABS_Y, y - rest_y);
	input_sync(&hdaps_idev);

	mod_timer(&hdaps_timer, jiffies + HDAPS_POLL_PERIOD);

out:
	up(&hdaps_sem);
}


/* Sysfs Files */

static ssize_t hdaps_position_show(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	int ret, x, y;

	ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
	if (ret)
		return ret;

	return sprintf(buf, "(%d,%d)\n", x, y);
}

static ssize_t hdaps_variance_show(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	int ret, x, y;

	ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
	if (ret)
		return ret;

	return sprintf(buf, "(%d,%d)\n", x, y);
}

static ssize_t hdaps_temp1_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	u8 temp;
	int ret;

	ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%u\n", temp);
}

static ssize_t hdaps_temp2_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	u8 temp;
	int ret;

	ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%u\n", temp);
}

static ssize_t hdaps_keyboard_activity_show(struct device *dev,
					    struct device_attribute *attr,
					    char *buf)
{
	return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
}

static ssize_t hdaps_mouse_activity_show(struct device *dev,
					 struct device_attribute *attr,
					 char *buf)
{
	return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
}

static ssize_t hdaps_calibrate_show(struct device *dev,
				    struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
}

static ssize_t hdaps_calibrate_store(struct device *dev,
				     struct device_attribute *attr,
				     const char *buf, size_t count)
{
	down(&hdaps_sem);
	hdaps_calibrate();
	up(&hdaps_sem);

	return count;
}

static ssize_t hdaps_invert_show(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "%u\n", hdaps_invert);
}

static ssize_t hdaps_invert_store(struct device *dev,
				  struct device_attribute *attr,
				  const char *buf, size_t count)
{
	int invert;

	if (sscanf(buf, "%d", &invert) != 1 || (invert != 1 && invert != 0))
		return -EINVAL;

	hdaps_invert = invert;
	hdaps_calibrate();

	return count;
}

static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);

static struct attribute *hdaps_attributes[] = {
	&dev_attr_position.attr,
	&dev_attr_variance.attr,
	&dev_attr_temp1.attr,
	&dev_attr_temp2.attr,
	&dev_attr_keyboard_activity.attr,
	&dev_attr_mouse_activity.attr,
	&dev_attr_calibrate.attr,
	&dev_attr_invert.attr,
	NULL,
};

static struct attribute_group hdaps_attribute_group = {
	.attrs = hdaps_attributes,
};


/* Module stuff */

/*
 * XXX: We should be able to return nonzero and halt the detection process.
 * But there is a bug in dmi_check_system() where a nonzero return from the
 * first match will result in a return of failure from dmi_check_system().
 * I fixed this; the patch is 2.6-git.  Once in a released tree, we can make
 * hdaps_dmi_match_invert() return hdaps_dmi_match(), which in turn returns 1.
 */
static int hdaps_dmi_match(struct dmi_system_id *id)
{
	printk(KERN_INFO "hdaps: %s detected.\n", id->ident);
	return 0;
}

static int hdaps_dmi_match_invert(struct dmi_system_id *id)
{
	hdaps_invert = 1;
	printk(KERN_INFO "hdaps: inverting axis readings.\n");
	return 0;
}

#define HDAPS_DMI_MATCH_NORMAL(model)	{		\
	.ident = "IBM " model,				\
	.callback = hdaps_dmi_match,			\
	.matches = {					\
		DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),	\
		DMI_MATCH(DMI_PRODUCT_VERSION, model)	\
	}						\
}

#define HDAPS_DMI_MATCH_INVERT(model)	{		\
	.ident = "IBM " model,				\
	.callback = hdaps_dmi_match_invert,		\
	.matches = {					\
		DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),	\
		DMI_MATCH(DMI_PRODUCT_VERSION, model)	\
	}						\
}

static int __init hdaps_init(void)
{
	int ret;

	/* Note that DMI_MATCH(...,"ThinkPad T42") will match "ThinkPad T42p" */
	struct dmi_system_id hdaps_whitelist[] = {
		HDAPS_DMI_MATCH_INVERT("ThinkPad R50p"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad R50"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad R51"),
		HDAPS_DMI_MATCH_INVERT("ThinkPad T41p"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad T41"),
		HDAPS_DMI_MATCH_INVERT("ThinkPad T42p"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad T42"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad T43"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad X40"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad X41 Tablet"),
		{ .ident = NULL }
	};

	if (!dmi_check_system(hdaps_whitelist)) {
		printk(KERN_WARNING "hdaps: supported laptop not found!\n");
		ret = -ENXIO;
		goto out;
	}

	if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
		ret = -ENXIO;
		goto out;
	}

	ret = driver_register(&hdaps_driver);
	if (ret)
		goto out_region;

	pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
	if (IS_ERR(pdev)) {
		ret = PTR_ERR(pdev);
		goto out_driver;
	}

	ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
	if (ret)
		goto out_device;

	/* initial calibrate for the input device */
	hdaps_calibrate();

	/* initialize the input class */
	hdaps_idev.dev = &pdev->dev;
	input_register_device(&hdaps_idev);

	/* start up our timer for the input device */
	init_timer(&hdaps_timer);
	hdaps_timer.function = hdaps_mousedev_poll;
	hdaps_timer.expires = jiffies + HDAPS_POLL_PERIOD;
	add_timer(&hdaps_timer);

	printk(KERN_INFO "hdaps: driver successfully loaded.\n");
	return 0;

out_device:
	platform_device_unregister(pdev);
out_driver:
	driver_unregister(&hdaps_driver);
out_region:
	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
out:
	printk(KERN_WARNING "hdaps: driver init failed (ret=%d)!\n", ret);
	return ret;
}

static void __exit hdaps_exit(void)
{
	del_timer_sync(&hdaps_timer);
	input_unregister_device(&hdaps_idev);
	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
	platform_device_unregister(pdev);
	driver_unregister(&hdaps_driver);
	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);

	printk(KERN_INFO "hdaps: driver unloaded.\n");
}

module_init(hdaps_init);
module_exit(hdaps_exit);

module_param_named(invert, hdaps_invert, bool, 0);
MODULE_PARM_DESC(invert, "invert data along each axis");

MODULE_AUTHOR("Robert Love");
MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
MODULE_LICENSE("GPL v2");