2 * drivers/hwmon/hdaps.c - driver for IBM's Hard Drive Active Protection System
4 * Copyright (C) 2005 Robert Love <rml@novell.com>
5 * Copyright (C) 2005 Jesper Juhl <jesper.juhl@gmail.com>
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.
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
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.
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
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
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>
38 #define HDAPS_LOW_PORT 0x1600 /* first port used by hdaps */
39 #define HDAPS_NR_PORTS 0x30 /* number of ports: 0x1600 - 0x162f */
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 */
51 #define STATE_FRESH 0x50 /* accelerometer data is fresh */
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? */
58 #define INIT_TIMEOUT_MSECS 4000 /* wait up to 4s for device init ... */
59 #define INIT_WAIT_MSECS 200 /* ... in 200ms increments */
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
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
;
73 static DECLARE_MUTEX(hdaps_sem
);
76 * __get_latch - Get the value from a given port. Callers must hold hdaps_sem.
78 static inline u8
__get_latch(u16 port
)
80 return inb(port
) & 0xff;
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.
87 static inline int __check_latch(u16 port
, u8 val
)
89 if (__get_latch(port
) == val
)
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.
98 static int __wait_latch(u16 port
, u8 val
)
102 for (i
= 0; i
< 20; i
++) {
103 if (!__check_latch(port
, val
))
112 * __device_refresh - request a refresh from the accelerometer. Does not wait
113 * for refresh to complete. Callers must hold hdaps_sem.
115 static void __device_refresh(void)
118 if (inb(0x1604) != STATE_FRESH
) {
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.
129 static int __device_refresh_sync(void)
132 return __wait_latch(0x1604, STATE_FRESH
);
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.
139 static inline void __device_complete(void)
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.
151 static int hdaps_readb_one(unsigned int port
, u8
*val
)
157 /* do a sync refresh -- we need to be sure that we read fresh data */
158 ret
= __device_refresh_sync();
170 /* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
171 static int __hdaps_read_pair(unsigned int port1
, unsigned int port2
,
174 /* do a sync refresh -- we need to be sure that we read fresh data */
175 if (__device_refresh_sync())
180 km_activity
= inb(HDAPS_PORT_KMACT
);
183 /* if hdaps_invert is set, negate the two values */
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.
196 static int hdaps_read_pair(unsigned int port1
, unsigned int port2
,
197 int *val1
, int *val2
)
202 ret
= __hdaps_read_pair(port1
, port2
, val1
, val2
);
209 * hdaps_device_init - initialize the accelerometer. Returns zero on success
210 * and negative error code on failure. Can sleep.
212 static int hdaps_device_init(void)
214 int total
, ret
= -ENXIO
;
220 if (__wait_latch(0x161f, 0x00))
224 * Most ThinkPads return 0x01.
226 * Others--namely the R50p, T41p, and T42p--return 0x03. These laptops
227 * have "inverted" axises.
229 * The 0x02 value occurs when the chip has been previously initialized.
231 if (__check_latch(0x1611, 0x03) &&
232 __check_latch(0x1611, 0x02) &&
233 __check_latch(0x1611, 0x01))
236 printk(KERN_DEBUG
"hdaps: initial latch check good (0x%02x).\n",
237 __get_latch(0x1611));
242 if (__wait_latch(0x161f, 0x00))
244 if (__wait_latch(0x1611, 0x00))
246 if (__wait_latch(0x1612, 0x60))
248 if (__wait_latch(0x1613, 0x00))
253 if (__wait_latch(0x161f, 0x00))
260 if (__wait_latch(0x161f, 0x00))
262 if (__device_refresh_sync())
264 if (__wait_latch(0x1611, 0x00))
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
) {
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)) {
278 msleep(INIT_WAIT_MSECS
);
287 /* Device model stuff */
289 static int hdaps_probe(struct platform_device
*dev
)
293 ret
= hdaps_device_init();
297 printk(KERN_INFO
"hdaps: device successfully initialized.\n");
301 static int hdaps_resume(struct platform_device
*dev
)
303 return hdaps_device_init();
306 static struct platform_driver hdaps_driver
= {
307 .probe
= hdaps_probe
,
308 .resume
= hdaps_resume
,
311 .owner
= THIS_MODULE
,
316 * hdaps_calibrate - Set our "resting" values. Callers must hold hdaps_sem.
318 static void hdaps_calibrate(void)
320 __hdaps_read_pair(HDAPS_PORT_XPOS
, HDAPS_PORT_YPOS
, &rest_x
, &rest_y
);
323 static void hdaps_mousedev_poll(unsigned long unused
)
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
);
333 if (__hdaps_read_pair(HDAPS_PORT_XPOS
, HDAPS_PORT_YPOS
, &x
, &y
))
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
);
340 mod_timer(&hdaps_timer
, jiffies
+ HDAPS_POLL_PERIOD
);
349 static ssize_t
hdaps_position_show(struct device
*dev
,
350 struct device_attribute
*attr
, char *buf
)
354 ret
= hdaps_read_pair(HDAPS_PORT_XPOS
, HDAPS_PORT_YPOS
, &x
, &y
);
358 return sprintf(buf
, "(%d,%d)\n", x
, y
);
361 static ssize_t
hdaps_variance_show(struct device
*dev
,
362 struct device_attribute
*attr
, char *buf
)
366 ret
= hdaps_read_pair(HDAPS_PORT_XVAR
, HDAPS_PORT_YVAR
, &x
, &y
);
370 return sprintf(buf
, "(%d,%d)\n", x
, y
);
373 static ssize_t
hdaps_temp1_show(struct device
*dev
,
374 struct device_attribute
*attr
, char *buf
)
379 ret
= hdaps_readb_one(HDAPS_PORT_TEMP1
, &temp
);
383 return sprintf(buf
, "%u\n", temp
);
386 static ssize_t
hdaps_temp2_show(struct device
*dev
,
387 struct device_attribute
*attr
, char *buf
)
392 ret
= hdaps_readb_one(HDAPS_PORT_TEMP2
, &temp
);
396 return sprintf(buf
, "%u\n", temp
);
399 static ssize_t
hdaps_keyboard_activity_show(struct device
*dev
,
400 struct device_attribute
*attr
,
403 return sprintf(buf
, "%u\n", KEYBD_ISSET(km_activity
));
406 static ssize_t
hdaps_mouse_activity_show(struct device
*dev
,
407 struct device_attribute
*attr
,
410 return sprintf(buf
, "%u\n", MOUSE_ISSET(km_activity
));
413 static ssize_t
hdaps_calibrate_show(struct device
*dev
,
414 struct device_attribute
*attr
, char *buf
)
416 return sprintf(buf
, "(%d,%d)\n", rest_x
, rest_y
);
419 static ssize_t
hdaps_calibrate_store(struct device
*dev
,
420 struct device_attribute
*attr
,
421 const char *buf
, size_t count
)
430 static ssize_t
hdaps_invert_show(struct device
*dev
,
431 struct device_attribute
*attr
, char *buf
)
433 return sprintf(buf
, "%u\n", hdaps_invert
);
436 static ssize_t
hdaps_invert_store(struct device
*dev
,
437 struct device_attribute
*attr
,
438 const char *buf
, size_t count
)
442 if (sscanf(buf
, "%d", &invert
) != 1 || (invert
!= 1 && invert
!= 0))
445 hdaps_invert
= invert
;
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
);
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
,
472 static struct attribute_group hdaps_attribute_group
= {
473 .attrs
= hdaps_attributes
,
479 /* hdaps_dmi_match - found a match. return one, short-circuiting the hunt. */
480 static int hdaps_dmi_match(struct dmi_system_id
*id
)
482 printk(KERN_INFO
"hdaps: %s detected.\n", id
->ident
);
486 /* hdaps_dmi_match_invert - found an inverted match. */
487 static int hdaps_dmi_match_invert(struct dmi_system_id
*id
)
490 printk(KERN_INFO
"hdaps: inverting axis readings.\n");
491 return hdaps_dmi_match(id
);
494 #define HDAPS_DMI_MATCH_NORMAL(model) { \
495 .ident = "IBM " model, \
496 .callback = hdaps_dmi_match, \
498 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"), \
499 DMI_MATCH(DMI_PRODUCT_VERSION, model) \
503 #define HDAPS_DMI_MATCH_INVERT(model) { \
504 .ident = "IBM " model, \
505 .callback = hdaps_dmi_match_invert, \
507 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"), \
508 DMI_MATCH(DMI_PRODUCT_VERSION, model) \
512 #define HDAPS_DMI_MATCH_LENOVO(model) { \
513 .ident = "Lenovo " model, \
514 .callback = hdaps_dmi_match_invert, \
516 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"), \
517 DMI_MATCH(DMI_PRODUCT_VERSION, model) \
521 static int __init
hdaps_init(void)
525 /* Note that DMI_MATCH(...,"ThinkPad T42") will match "ThinkPad T42p" */
526 struct dmi_system_id hdaps_whitelist
[] = {
527 HDAPS_DMI_MATCH_NORMAL("ThinkPad H"),
528 HDAPS_DMI_MATCH_INVERT("ThinkPad R50p"),
529 HDAPS_DMI_MATCH_NORMAL("ThinkPad R50"),
530 HDAPS_DMI_MATCH_NORMAL("ThinkPad R51"),
531 HDAPS_DMI_MATCH_NORMAL("ThinkPad R52"),
532 HDAPS_DMI_MATCH_INVERT("ThinkPad T41p"),
533 HDAPS_DMI_MATCH_NORMAL("ThinkPad T41"),
534 HDAPS_DMI_MATCH_INVERT("ThinkPad T42p"),
535 HDAPS_DMI_MATCH_NORMAL("ThinkPad T42"),
536 HDAPS_DMI_MATCH_NORMAL("ThinkPad T43"),
537 HDAPS_DMI_MATCH_LENOVO("ThinkPad T60p"),
538 HDAPS_DMI_MATCH_NORMAL("ThinkPad X40"),
539 HDAPS_DMI_MATCH_NORMAL("ThinkPad X41 Tablet"),
540 HDAPS_DMI_MATCH_NORMAL("ThinkPad X41"),
541 HDAPS_DMI_MATCH_LENOVO("ThinkPad X60"),
545 if (!dmi_check_system(hdaps_whitelist
)) {
546 printk(KERN_WARNING
"hdaps: supported laptop not found!\n");
551 if (!request_region(HDAPS_LOW_PORT
, HDAPS_NR_PORTS
, "hdaps")) {
556 ret
= platform_driver_register(&hdaps_driver
);
560 pdev
= platform_device_register_simple("hdaps", -1, NULL
, 0);
566 ret
= sysfs_create_group(&pdev
->dev
.kobj
, &hdaps_attribute_group
);
570 hdaps_idev
= input_allocate_device();
576 /* initial calibrate for the input device */
579 /* initialize the input class */
580 hdaps_idev
->name
= "hdaps";
581 hdaps_idev
->cdev
.dev
= &pdev
->dev
;
582 hdaps_idev
->evbit
[0] = BIT(EV_ABS
);
583 input_set_abs_params(hdaps_idev
, ABS_X
,
584 -256, 256, HDAPS_INPUT_FUZZ
, HDAPS_INPUT_FLAT
);
585 input_set_abs_params(hdaps_idev
, ABS_Y
,
586 -256, 256, HDAPS_INPUT_FUZZ
, HDAPS_INPUT_FLAT
);
588 input_register_device(hdaps_idev
);
590 /* start up our timer for the input device */
591 init_timer(&hdaps_timer
);
592 hdaps_timer
.function
= hdaps_mousedev_poll
;
593 hdaps_timer
.expires
= jiffies
+ HDAPS_POLL_PERIOD
;
594 add_timer(&hdaps_timer
);
596 printk(KERN_INFO
"hdaps: driver successfully loaded.\n");
600 sysfs_remove_group(&pdev
->dev
.kobj
, &hdaps_attribute_group
);
602 platform_device_unregister(pdev
);
604 platform_driver_unregister(&hdaps_driver
);
606 release_region(HDAPS_LOW_PORT
, HDAPS_NR_PORTS
);
608 printk(KERN_WARNING
"hdaps: driver init failed (ret=%d)!\n", ret
);
612 static void __exit
hdaps_exit(void)
614 del_timer_sync(&hdaps_timer
);
615 input_unregister_device(hdaps_idev
);
616 sysfs_remove_group(&pdev
->dev
.kobj
, &hdaps_attribute_group
);
617 platform_device_unregister(pdev
);
618 platform_driver_unregister(&hdaps_driver
);
619 release_region(HDAPS_LOW_PORT
, HDAPS_NR_PORTS
);
621 printk(KERN_INFO
"hdaps: driver unloaded.\n");
624 module_init(hdaps_init
);
625 module_exit(hdaps_exit
);
627 module_param_named(invert
, hdaps_invert
, bool, 0);
628 MODULE_PARM_DESC(invert
, "invert data along each axis");
630 MODULE_AUTHOR("Robert Love");
631 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
632 MODULE_LICENSE("GPL v2");