Merge with http://kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
[linux-2.6] / drivers / hwmon / hdaps.c
1 /*
2  * drivers/hwmon/hdaps.c - driver for IBM's Hard Drive Active Protection System
3  *
4  * Copyright (C) 2005 Robert Love <rml@novell.com>
5  * Copyright (C) 2005 Jesper Juhl <jesper.juhl@gmail.com>
6  *
7  * The HardDisk Active Protection System (hdaps) is present in IBM ThinkPads
8  * starting with the R40, T41, and X40.  It provides a basic two-axis
9  * accelerometer and other data, such as the device's temperature.
10  *
11  * This driver is based on the document by Mark A. Smith available at
12  * http://www.almaden.ibm.com/cs/people/marksmith/tpaps.html and a lot of trial
13  * and error.
14  *
15  * This program is free software; you can redistribute it and/or modify it
16  * under the terms of the GNU General Public License v2 as published by the
17  * Free Software Foundation.
18  *
19  * This program is distributed in the hope that it will be useful, but WITHOUT
20  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
21  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
22  * more details.
23  *
24  * You should have received a copy of the GNU General Public License along with
25  * this program; if not, write to the Free Software Foundation, Inc.,
26  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
27  */
28
29 #include <linux/delay.h>
30 #include <linux/platform_device.h>
31 #include <linux/input.h>
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/timer.h>
35 #include <linux/dmi.h>
36 #include <asm/io.h>
37
38 #define HDAPS_LOW_PORT          0x1600  /* first port used by hdaps */
39 #define HDAPS_NR_PORTS          0x30    /* number of ports: 0x1600 - 0x162f */
40
41 #define HDAPS_PORT_STATE        0x1611  /* device state */
42 #define HDAPS_PORT_YPOS         0x1612  /* y-axis position */
43 #define HDAPS_PORT_XPOS         0x1614  /* x-axis position */
44 #define HDAPS_PORT_TEMP1        0x1616  /* device temperature, in celcius */
45 #define HDAPS_PORT_YVAR         0x1617  /* y-axis variance (what is this?) */
46 #define HDAPS_PORT_XVAR         0x1619  /* x-axis variance (what is this?) */
47 #define HDAPS_PORT_TEMP2        0x161b  /* device temperature (again?) */
48 #define HDAPS_PORT_UNKNOWN      0x161c  /* what is this? */
49 #define HDAPS_PORT_KMACT        0x161d  /* keyboard or mouse activity */
50
51 #define STATE_FRESH             0x50    /* accelerometer data is fresh */
52
53 #define KEYBD_MASK              0x20    /* set if keyboard activity */
54 #define MOUSE_MASK              0x40    /* set if mouse activity */
55 #define KEYBD_ISSET(n)          (!! (n & KEYBD_MASK))   /* keyboard used? */
56 #define MOUSE_ISSET(n)          (!! (n & MOUSE_MASK))   /* mouse used? */
57
58 #define INIT_TIMEOUT_MSECS      4000    /* wait up to 4s for device init ... */
59 #define INIT_WAIT_MSECS         200     /* ... in 200ms increments */
60
61 #define HDAPS_POLL_PERIOD       (HZ/20) /* poll for input every 1/20s */
62 #define HDAPS_INPUT_FUZZ        4       /* input event threshold */
63 #define HDAPS_INPUT_FLAT        4
64
65 static struct timer_list hdaps_timer;
66 static struct platform_device *pdev;
67 static struct input_dev *hdaps_idev;
68 static unsigned int hdaps_invert;
69 static u8 km_activity;
70 static int rest_x;
71 static int rest_y;
72
73 static DECLARE_MUTEX(hdaps_sem);
74
75 /*
76  * __get_latch - Get the value from a given port.  Callers must hold hdaps_sem.
77  */
78 static inline u8 __get_latch(u16 port)
79 {
80         return inb(port) & 0xff;
81 }
82
83 /*
84  * __check_latch - Check a port latch for a given value.  Returns zero if the
85  * port contains the given value.  Callers must hold hdaps_sem.
86  */
87 static inline int __check_latch(u16 port, u8 val)
88 {
89         if (__get_latch(port) == val)
90                 return 0;
91         return -EINVAL;
92 }
93
94 /*
95  * __wait_latch - Wait up to 100us for a port latch to get a certain value,
96  * returning zero if the value is obtained.  Callers must hold hdaps_sem.
97  */
98 static int __wait_latch(u16 port, u8 val)
99 {
100         unsigned int i;
101
102         for (i = 0; i < 20; i++) {
103                 if (!__check_latch(port, val))
104                         return 0;
105                 udelay(5);
106         }
107
108         return -EIO;
109 }
110
111 /*
112  * __device_refresh - request a refresh from the accelerometer.  Does not wait
113  * for refresh to complete.  Callers must hold hdaps_sem.
114  */
115 static void __device_refresh(void)
116 {
117         udelay(200);
118         if (inb(0x1604) != STATE_FRESH) {
119                 outb(0x11, 0x1610);
120                 outb(0x01, 0x161f);
121         }
122 }
123
124 /*
125  * __device_refresh_sync - request a synchronous refresh from the
126  * accelerometer.  We wait for the refresh to complete.  Returns zero if
127  * successful and nonzero on error.  Callers must hold hdaps_sem.
128  */
129 static int __device_refresh_sync(void)
130 {
131         __device_refresh();
132         return __wait_latch(0x1604, STATE_FRESH);
133 }
134
135 /*
136  * __device_complete - indicate to the accelerometer that we are done reading
137  * data, and then initiate an async refresh.  Callers must hold hdaps_sem.
138  */
139 static inline void __device_complete(void)
140 {
141         inb(0x161f);
142         inb(0x1604);
143         __device_refresh();
144 }
145
146 /*
147  * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
148  * the given pointer.  Returns zero on success or a negative error on failure.
149  * Can sleep.
150  */
151 static int hdaps_readb_one(unsigned int port, u8 *val)
152 {
153         int ret;
154
155         down(&hdaps_sem);
156
157         /* do a sync refresh -- we need to be sure that we read fresh data */
158         ret = __device_refresh_sync();
159         if (ret)
160                 goto out;
161
162         *val = inb(port);
163         __device_complete();
164
165 out:
166         up(&hdaps_sem);
167         return ret;
168 }
169
170 /* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
171 static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
172                              int *x, int *y)
173 {
174         /* do a sync refresh -- we need to be sure that we read fresh data */
175         if (__device_refresh_sync())
176                 return -EIO;
177
178         *y = inw(port2);
179         *x = inw(port1);
180         km_activity = inb(HDAPS_PORT_KMACT);
181         __device_complete();
182
183         /* if hdaps_invert is set, negate the two values */
184         if (hdaps_invert) {
185                 *x = -*x;
186                 *y = -*y;
187         }
188
189         return 0;
190 }
191
192 /*
193  * hdaps_read_pair - reads the values from a pair of ports, placing the values
194  * in the given pointers.  Returns zero on success.  Can sleep.
195  */
196 static int hdaps_read_pair(unsigned int port1, unsigned int port2,
197                            int *val1, int *val2)
198 {
199         int ret;
200
201         down(&hdaps_sem);
202         ret = __hdaps_read_pair(port1, port2, val1, val2);
203         up(&hdaps_sem);
204
205         return ret;
206 }
207
208 /*
209  * hdaps_device_init - initialize the accelerometer.  Returns zero on success
210  * and negative error code on failure.  Can sleep.
211  */
212 static int hdaps_device_init(void)
213 {
214         int total, ret = -ENXIO;
215
216         down(&hdaps_sem);
217
218         outb(0x13, 0x1610);
219         outb(0x01, 0x161f);
220         if (__wait_latch(0x161f, 0x00))
221                 goto out;
222
223         /*
224          * Most ThinkPads return 0x01.
225          *
226          * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
227          * have "inverted" axises.
228          *
229          * The 0x02 value occurs when the chip has been previously initialized.
230          */
231         if (__check_latch(0x1611, 0x03) &&
232                      __check_latch(0x1611, 0x02) &&
233                      __check_latch(0x1611, 0x01))
234                 goto out;
235
236         printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
237                __get_latch(0x1611));
238
239         outb(0x17, 0x1610);
240         outb(0x81, 0x1611);
241         outb(0x01, 0x161f);
242         if (__wait_latch(0x161f, 0x00))
243                 goto out;
244         if (__wait_latch(0x1611, 0x00))
245                 goto out;
246         if (__wait_latch(0x1612, 0x60))
247                 goto out;
248         if (__wait_latch(0x1613, 0x00))
249                 goto out;
250         outb(0x14, 0x1610);
251         outb(0x01, 0x1611);
252         outb(0x01, 0x161f);
253         if (__wait_latch(0x161f, 0x00))
254                 goto out;
255         outb(0x10, 0x1610);
256         outb(0xc8, 0x1611);
257         outb(0x00, 0x1612);
258         outb(0x02, 0x1613);
259         outb(0x01, 0x161f);
260         if (__wait_latch(0x161f, 0x00))
261                 goto out;
262         if (__device_refresh_sync())
263                 goto out;
264         if (__wait_latch(0x1611, 0x00))
265                 goto out;
266
267         /* we have done our dance, now let's wait for the applause */
268         for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
269                 int x, y;
270
271                 /* a read of the device helps push it into action */
272                 __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
273                 if (!__wait_latch(0x1611, 0x02)) {
274                         ret = 0;
275                         break;
276                 }
277
278                 msleep(INIT_WAIT_MSECS);
279         }
280
281 out:
282         up(&hdaps_sem);
283         return ret;
284 }
285
286
287 /* Device model stuff */
288
289 static int hdaps_probe(struct platform_device *dev)
290 {
291         int ret;
292
293         ret = hdaps_device_init();
294         if (ret)
295                 return ret;
296
297         printk(KERN_INFO "hdaps: device successfully initialized.\n");
298         return 0;
299 }
300
301 static int hdaps_resume(struct platform_device *dev)
302 {
303         return hdaps_device_init();
304 }
305
306 static struct platform_driver hdaps_driver = {
307         .probe = hdaps_probe,
308         .resume = hdaps_resume,
309         .driver = {
310                 .name = "hdaps",
311                 .owner = THIS_MODULE,
312         },
313 };
314
315 /*
316  * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_sem.
317  */
318 static void hdaps_calibrate(void)
319 {
320         __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
321 }
322
323 static void hdaps_mousedev_poll(unsigned long unused)
324 {
325         int x, y;
326
327         /* Cannot sleep.  Try nonblockingly.  If we fail, try again later. */
328         if (down_trylock(&hdaps_sem)) {
329                 mod_timer(&hdaps_timer,jiffies + HDAPS_POLL_PERIOD);
330                 return;
331         }
332
333         if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
334                 goto out;
335
336         input_report_abs(hdaps_idev, ABS_X, x - rest_x);
337         input_report_abs(hdaps_idev, ABS_Y, y - rest_y);
338         input_sync(hdaps_idev);
339
340         mod_timer(&hdaps_timer, jiffies + HDAPS_POLL_PERIOD);
341
342 out:
343         up(&hdaps_sem);
344 }
345
346
347 /* Sysfs Files */
348
349 static ssize_t hdaps_position_show(struct device *dev,
350                                    struct device_attribute *attr, char *buf)
351 {
352         int ret, x, y;
353
354         ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
355         if (ret)
356                 return ret;
357
358         return sprintf(buf, "(%d,%d)\n", x, y);
359 }
360
361 static ssize_t hdaps_variance_show(struct device *dev,
362                                    struct device_attribute *attr, char *buf)
363 {
364         int ret, x, y;
365
366         ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
367         if (ret)
368                 return ret;
369
370         return sprintf(buf, "(%d,%d)\n", x, y);
371 }
372
373 static ssize_t hdaps_temp1_show(struct device *dev,
374                                 struct device_attribute *attr, char *buf)
375 {
376         u8 temp;
377         int ret;
378
379         ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
380         if (ret < 0)
381                 return ret;
382
383         return sprintf(buf, "%u\n", temp);
384 }
385
386 static ssize_t hdaps_temp2_show(struct device *dev,
387                                 struct device_attribute *attr, char *buf)
388 {
389         u8 temp;
390         int ret;
391
392         ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
393         if (ret < 0)
394                 return ret;
395
396         return sprintf(buf, "%u\n", temp);
397 }
398
399 static ssize_t hdaps_keyboard_activity_show(struct device *dev,
400                                             struct device_attribute *attr,
401                                             char *buf)
402 {
403         return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
404 }
405
406 static ssize_t hdaps_mouse_activity_show(struct device *dev,
407                                          struct device_attribute *attr,
408                                          char *buf)
409 {
410         return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
411 }
412
413 static ssize_t hdaps_calibrate_show(struct device *dev,
414                                     struct device_attribute *attr, char *buf)
415 {
416         return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
417 }
418
419 static ssize_t hdaps_calibrate_store(struct device *dev,
420                                      struct device_attribute *attr,
421                                      const char *buf, size_t count)
422 {
423         down(&hdaps_sem);
424         hdaps_calibrate();
425         up(&hdaps_sem);
426
427         return count;
428 }
429
430 static ssize_t hdaps_invert_show(struct device *dev,
431                                  struct device_attribute *attr, char *buf)
432 {
433         return sprintf(buf, "%u\n", hdaps_invert);
434 }
435
436 static ssize_t hdaps_invert_store(struct device *dev,
437                                   struct device_attribute *attr,
438                                   const char *buf, size_t count)
439 {
440         int invert;
441
442         if (sscanf(buf, "%d", &invert) != 1 || (invert != 1 && invert != 0))
443                 return -EINVAL;
444
445         hdaps_invert = invert;
446         hdaps_calibrate();
447
448         return count;
449 }
450
451 static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
452 static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
453 static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
454 static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
455 static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
456 static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
457 static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
458 static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
459
460 static struct attribute *hdaps_attributes[] = {
461         &dev_attr_position.attr,
462         &dev_attr_variance.attr,
463         &dev_attr_temp1.attr,
464         &dev_attr_temp2.attr,
465         &dev_attr_keyboard_activity.attr,
466         &dev_attr_mouse_activity.attr,
467         &dev_attr_calibrate.attr,
468         &dev_attr_invert.attr,
469         NULL,
470 };
471
472 static struct attribute_group hdaps_attribute_group = {
473         .attrs = hdaps_attributes,
474 };
475
476
477 /* Module stuff */
478
479 /* hdaps_dmi_match - found a match.  return one, short-circuiting the hunt. */
480 static int hdaps_dmi_match(struct dmi_system_id *id)
481 {
482         printk(KERN_INFO "hdaps: %s detected.\n", id->ident);
483         return 1;
484 }
485
486 /* hdaps_dmi_match_invert - found an inverted match. */
487 static int hdaps_dmi_match_invert(struct dmi_system_id *id)
488 {
489         hdaps_invert = 1;
490         printk(KERN_INFO "hdaps: inverting axis readings.\n");
491         return hdaps_dmi_match(id);
492 }
493
494 #define HDAPS_DMI_MATCH_NORMAL(model)   {               \
495         .ident = "IBM " model,                          \
496         .callback = hdaps_dmi_match,                    \
497         .matches = {                                    \
498                 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),     \
499                 DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
500         }                                               \
501 }
502
503 #define HDAPS_DMI_MATCH_INVERT(model)   {               \
504         .ident = "IBM " model,                          \
505         .callback = hdaps_dmi_match_invert,             \
506         .matches = {                                    \
507                 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),     \
508                 DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
509         }                                               \
510 }
511
512 static int __init hdaps_init(void)
513 {
514         int ret;
515
516         /* Note that DMI_MATCH(...,"ThinkPad T42") will match "ThinkPad T42p" */
517         struct dmi_system_id hdaps_whitelist[] = {
518                 HDAPS_DMI_MATCH_INVERT("ThinkPad R50p"),
519                 HDAPS_DMI_MATCH_NORMAL("ThinkPad R50"),
520                 HDAPS_DMI_MATCH_NORMAL("ThinkPad R51"),
521                 HDAPS_DMI_MATCH_NORMAL("ThinkPad R52"),
522                 HDAPS_DMI_MATCH_INVERT("ThinkPad T41p"),
523                 HDAPS_DMI_MATCH_NORMAL("ThinkPad T41"),
524                 HDAPS_DMI_MATCH_INVERT("ThinkPad T42p"),
525                 HDAPS_DMI_MATCH_NORMAL("ThinkPad T42"),
526                 HDAPS_DMI_MATCH_NORMAL("ThinkPad T43"),
527                 HDAPS_DMI_MATCH_NORMAL("ThinkPad X40"),
528                 HDAPS_DMI_MATCH_NORMAL("ThinkPad X41 Tablet"),
529                 HDAPS_DMI_MATCH_NORMAL("ThinkPad X41"),
530                 { .ident = NULL }
531         };
532
533         if (!dmi_check_system(hdaps_whitelist)) {
534                 printk(KERN_WARNING "hdaps: supported laptop not found!\n");
535                 ret = -ENXIO;
536                 goto out;
537         }
538
539         if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
540                 ret = -ENXIO;
541                 goto out;
542         }
543
544         ret = platform_driver_register(&hdaps_driver);
545         if (ret)
546                 goto out_region;
547
548         pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
549         if (IS_ERR(pdev)) {
550                 ret = PTR_ERR(pdev);
551                 goto out_driver;
552         }
553
554         ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
555         if (ret)
556                 goto out_device;
557
558         hdaps_idev = input_allocate_device();
559         if (!hdaps_idev) {
560                 ret = -ENOMEM;
561                 goto out_group;
562         }
563
564         /* initial calibrate for the input device */
565         hdaps_calibrate();
566
567         /* initialize the input class */
568         hdaps_idev->name = "hdaps";
569         hdaps_idev->cdev.dev = &pdev->dev;
570         hdaps_idev->evbit[0] = BIT(EV_ABS);
571         input_set_abs_params(hdaps_idev, ABS_X,
572                         -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
573         input_set_abs_params(hdaps_idev, ABS_X,
574                         -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
575
576         input_register_device(hdaps_idev);
577
578         /* start up our timer for the input device */
579         init_timer(&hdaps_timer);
580         hdaps_timer.function = hdaps_mousedev_poll;
581         hdaps_timer.expires = jiffies + HDAPS_POLL_PERIOD;
582         add_timer(&hdaps_timer);
583
584         printk(KERN_INFO "hdaps: driver successfully loaded.\n");
585         return 0;
586
587 out_group:
588         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
589 out_device:
590         platform_device_unregister(pdev);
591 out_driver:
592         platform_driver_unregister(&hdaps_driver);
593 out_region:
594         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
595 out:
596         printk(KERN_WARNING "hdaps: driver init failed (ret=%d)!\n", ret);
597         return ret;
598 }
599
600 static void __exit hdaps_exit(void)
601 {
602         del_timer_sync(&hdaps_timer);
603         input_unregister_device(hdaps_idev);
604         sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
605         platform_device_unregister(pdev);
606         platform_driver_unregister(&hdaps_driver);
607         release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
608
609         printk(KERN_INFO "hdaps: driver unloaded.\n");
610 }
611
612 module_init(hdaps_init);
613 module_exit(hdaps_exit);
614
615 module_param_named(invert, hdaps_invert, bool, 0);
616 MODULE_PARM_DESC(invert, "invert data along each axis");
617
618 MODULE_AUTHOR("Robert Love");
619 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
620 MODULE_LICENSE("GPL v2");