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>
36 #include <linux/jiffies.h>
39 #define HDAPS_LOW_PORT 0x1600 /* first port used by hdaps */
40 #define HDAPS_NR_PORTS 0x30 /* number of ports: 0x1600 - 0x162f */
42 #define HDAPS_PORT_STATE 0x1611 /* device state */
43 #define HDAPS_PORT_YPOS 0x1612 /* y-axis position */
44 #define HDAPS_PORT_XPOS 0x1614 /* x-axis position */
45 #define HDAPS_PORT_TEMP1 0x1616 /* device temperature, in Celsius */
46 #define HDAPS_PORT_YVAR 0x1617 /* y-axis variance (what is this?) */
47 #define HDAPS_PORT_XVAR 0x1619 /* x-axis variance (what is this?) */
48 #define HDAPS_PORT_TEMP2 0x161b /* device temperature (again?) */
49 #define HDAPS_PORT_UNKNOWN 0x161c /* what is this? */
50 #define HDAPS_PORT_KMACT 0x161d /* keyboard or mouse activity */
52 #define STATE_FRESH 0x50 /* accelerometer data is fresh */
54 #define KEYBD_MASK 0x20 /* set if keyboard activity */
55 #define MOUSE_MASK 0x40 /* set if mouse activity */
56 #define KEYBD_ISSET(n) (!! (n & KEYBD_MASK)) /* keyboard used? */
57 #define MOUSE_ISSET(n) (!! (n & MOUSE_MASK)) /* mouse used? */
59 #define INIT_TIMEOUT_MSECS 4000 /* wait up to 4s for device init ... */
60 #define INIT_WAIT_MSECS 200 /* ... in 200ms increments */
62 #define HDAPS_POLL_PERIOD (HZ/20) /* poll for input every 1/20s */
63 #define HDAPS_INPUT_FUZZ 4 /* input event threshold */
64 #define HDAPS_INPUT_FLAT 4
66 static struct timer_list hdaps_timer;
67 static struct platform_device *pdev;
68 static struct input_dev *hdaps_idev;
69 static unsigned int hdaps_invert;
70 static u8 km_activity;
74 static DECLARE_MUTEX(hdaps_sem);
77 * __get_latch - Get the value from a given port. Callers must hold hdaps_sem.
79 static inline u8 __get_latch(u16 port)
81 return inb(port) & 0xff;
85 * __check_latch - Check a port latch for a given value. Returns zero if the
86 * port contains the given value. Callers must hold hdaps_sem.
88 static inline int __check_latch(u16 port, u8 val)
90 if (__get_latch(port) == val)
96 * __wait_latch - Wait up to 100us for a port latch to get a certain value,
97 * returning zero if the value is obtained. Callers must hold hdaps_sem.
99 static int __wait_latch(u16 port, u8 val)
103 for (i = 0; i < 20; i++) {
104 if (!__check_latch(port, val))
113 * __device_refresh - request a refresh from the accelerometer. Does not wait
114 * for refresh to complete. Callers must hold hdaps_sem.
116 static void __device_refresh(void)
119 if (inb(0x1604) != STATE_FRESH) {
126 * __device_refresh_sync - request a synchronous refresh from the
127 * accelerometer. We wait for the refresh to complete. Returns zero if
128 * successful and nonzero on error. Callers must hold hdaps_sem.
130 static int __device_refresh_sync(void)
133 return __wait_latch(0x1604, STATE_FRESH);
137 * __device_complete - indicate to the accelerometer that we are done reading
138 * data, and then initiate an async refresh. Callers must hold hdaps_sem.
140 static inline void __device_complete(void)
148 * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
149 * the given pointer. Returns zero on success or a negative error on failure.
152 static int hdaps_readb_one(unsigned int port, u8 *val)
158 /* do a sync refresh -- we need to be sure that we read fresh data */
159 ret = __device_refresh_sync();
171 /* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
172 static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
175 /* do a sync refresh -- we need to be sure that we read fresh data */
176 if (__device_refresh_sync())
181 km_activity = inb(HDAPS_PORT_KMACT);
184 /* if hdaps_invert is set, negate the two values */
194 * hdaps_read_pair - reads the values from a pair of ports, placing the values
195 * in the given pointers. Returns zero on success. Can sleep.
197 static int hdaps_read_pair(unsigned int port1, unsigned int port2,
198 int *val1, int *val2)
203 ret = __hdaps_read_pair(port1, port2, val1, val2);
210 * hdaps_device_init - initialize the accelerometer. Returns zero on success
211 * and negative error code on failure. Can sleep.
213 static int hdaps_device_init(void)
215 int total, ret = -ENXIO;
221 if (__wait_latch(0x161f, 0x00))
225 * Most ThinkPads return 0x01.
227 * Others--namely the R50p, T41p, and T42p--return 0x03. These laptops
228 * have "inverted" axises.
230 * The 0x02 value occurs when the chip has been previously initialized.
232 if (__check_latch(0x1611, 0x03) &&
233 __check_latch(0x1611, 0x02) &&
234 __check_latch(0x1611, 0x01))
237 printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
238 __get_latch(0x1611));
243 if (__wait_latch(0x161f, 0x00))
245 if (__wait_latch(0x1611, 0x00))
247 if (__wait_latch(0x1612, 0x60))
249 if (__wait_latch(0x1613, 0x00))
254 if (__wait_latch(0x161f, 0x00))
261 if (__wait_latch(0x161f, 0x00))
263 if (__device_refresh_sync())
265 if (__wait_latch(0x1611, 0x00))
268 /* we have done our dance, now let's wait for the applause */
269 for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
272 /* a read of the device helps push it into action */
273 __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
274 if (!__wait_latch(0x1611, 0x02)) {
279 msleep(INIT_WAIT_MSECS);
288 /* Device model stuff */
290 static int hdaps_probe(struct platform_device *dev)
294 ret = hdaps_device_init();
298 printk(KERN_INFO "hdaps: device successfully initialized.\n");
302 static int hdaps_resume(struct platform_device *dev)
304 return hdaps_device_init();
307 static struct platform_driver hdaps_driver = {
308 .probe = hdaps_probe,
309 .resume = hdaps_resume,
312 .owner = THIS_MODULE,
317 * hdaps_calibrate - Set our "resting" values. Callers must hold hdaps_sem.
319 static void hdaps_calibrate(void)
321 __hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
324 static void hdaps_mousedev_poll(unsigned long unused)
328 /* Cannot sleep. Try nonblockingly. If we fail, try again later. */
329 if (down_trylock(&hdaps_sem)) {
330 mod_timer(&hdaps_timer,jiffies + HDAPS_POLL_PERIOD);
334 if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
337 input_report_abs(hdaps_idev, ABS_X, x - rest_x);
338 input_report_abs(hdaps_idev, ABS_Y, y - rest_y);
339 input_sync(hdaps_idev);
341 mod_timer(&hdaps_timer, jiffies + HDAPS_POLL_PERIOD);
350 static ssize_t hdaps_position_show(struct device *dev,
351 struct device_attribute *attr, char *buf)
355 ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
359 return sprintf(buf, "(%d,%d)\n", x, y);
362 static ssize_t hdaps_variance_show(struct device *dev,
363 struct device_attribute *attr, char *buf)
367 ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
371 return sprintf(buf, "(%d,%d)\n", x, y);
374 static ssize_t hdaps_temp1_show(struct device *dev,
375 struct device_attribute *attr, char *buf)
380 ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
384 return sprintf(buf, "%u\n", temp);
387 static ssize_t hdaps_temp2_show(struct device *dev,
388 struct device_attribute *attr, char *buf)
393 ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
397 return sprintf(buf, "%u\n", temp);
400 static ssize_t hdaps_keyboard_activity_show(struct device *dev,
401 struct device_attribute *attr,
404 return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
407 static ssize_t hdaps_mouse_activity_show(struct device *dev,
408 struct device_attribute *attr,
411 return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
414 static ssize_t hdaps_calibrate_show(struct device *dev,
415 struct device_attribute *attr, char *buf)
417 return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
420 static ssize_t hdaps_calibrate_store(struct device *dev,
421 struct device_attribute *attr,
422 const char *buf, size_t count)
431 static ssize_t hdaps_invert_show(struct device *dev,
432 struct device_attribute *attr, char *buf)
434 return sprintf(buf, "%u\n", hdaps_invert);
437 static ssize_t hdaps_invert_store(struct device *dev,
438 struct device_attribute *attr,
439 const char *buf, size_t count)
443 if (sscanf(buf, "%d", &invert) != 1 || (invert != 1 && invert != 0))
446 hdaps_invert = invert;
452 static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
453 static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
454 static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
455 static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
456 static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
457 static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
458 static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
459 static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
461 static struct attribute *hdaps_attributes[] = {
462 &dev_attr_position.attr,
463 &dev_attr_variance.attr,
464 &dev_attr_temp1.attr,
465 &dev_attr_temp2.attr,
466 &dev_attr_keyboard_activity.attr,
467 &dev_attr_mouse_activity.attr,
468 &dev_attr_calibrate.attr,
469 &dev_attr_invert.attr,
473 static struct attribute_group hdaps_attribute_group = {
474 .attrs = hdaps_attributes,
480 /* hdaps_dmi_match - found a match. return one, short-circuiting the hunt. */
481 static int __init hdaps_dmi_match(struct dmi_system_id *id)
483 printk(KERN_INFO "hdaps: %s detected.\n", id->ident);
487 /* hdaps_dmi_match_invert - found an inverted match. */
488 static int __init hdaps_dmi_match_invert(struct dmi_system_id *id)
491 printk(KERN_INFO "hdaps: inverting axis readings.\n");
492 return hdaps_dmi_match(id);
495 #define HDAPS_DMI_MATCH_NORMAL(vendor, model) { \
496 .ident = vendor " " model, \
497 .callback = hdaps_dmi_match, \
499 DMI_MATCH(DMI_BOARD_VENDOR, vendor), \
500 DMI_MATCH(DMI_PRODUCT_VERSION, model) \
504 #define HDAPS_DMI_MATCH_INVERT(vendor, model) { \
505 .ident = vendor " " model, \
506 .callback = hdaps_dmi_match_invert, \
508 DMI_MATCH(DMI_BOARD_VENDOR, vendor), \
509 DMI_MATCH(DMI_PRODUCT_VERSION, model) \
513 /* Note that HDAPS_DMI_MATCH_NORMAL("ThinkPad T42") would match
514 "ThinkPad T42p", so the order of the entries matters.
515 If your ThinkPad is not recognized, please update to latest
516 BIOS. This is especially the case for some R52 ThinkPads. */
517 static struct dmi_system_id __initdata hdaps_whitelist[] = {
518 HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad R50p"),
519 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R50"),
520 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R51"),
521 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R52"),
522 HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T41p"),
523 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T41"),
524 HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T42p"),
525 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T42"),
526 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T43"),
527 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T60"),
528 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X40"),
529 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X41"),
530 HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X60"),
531 HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad Z60m"),
535 static int __init hdaps_init(void)
539 if (!dmi_check_system(hdaps_whitelist)) {
540 printk(KERN_WARNING "hdaps: supported laptop not found!\n");
545 if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
550 ret = platform_driver_register(&hdaps_driver);
554 pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
560 ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
564 hdaps_idev = input_allocate_device();
570 /* initial calibrate for the input device */
573 /* initialize the input class */
574 hdaps_idev->name = "hdaps";
575 hdaps_idev->cdev.dev = &pdev->dev;
576 hdaps_idev->evbit[0] = BIT(EV_ABS);
577 input_set_abs_params(hdaps_idev, ABS_X,
578 -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
579 input_set_abs_params(hdaps_idev, ABS_Y,
580 -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
582 ret = input_register_device(hdaps_idev);
586 /* start up our timer for the input device */
587 init_timer(&hdaps_timer);
588 hdaps_timer.function = hdaps_mousedev_poll;
589 hdaps_timer.expires = jiffies + HDAPS_POLL_PERIOD;
590 add_timer(&hdaps_timer);
592 printk(KERN_INFO "hdaps: driver successfully loaded.\n");
596 input_free_device(hdaps_idev);
598 sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
600 platform_device_unregister(pdev);
602 platform_driver_unregister(&hdaps_driver);
604 release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
606 printk(KERN_WARNING "hdaps: driver init failed (ret=%d)!\n", ret);
610 static void __exit hdaps_exit(void)
612 del_timer_sync(&hdaps_timer);
613 input_unregister_device(hdaps_idev);
614 sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
615 platform_device_unregister(pdev);
616 platform_driver_unregister(&hdaps_driver);
617 release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
619 printk(KERN_INFO "hdaps: driver unloaded.\n");
622 module_init(hdaps_init);
623 module_exit(hdaps_exit);
625 module_param_named(invert, hdaps_invert, bool, 0);
626 MODULE_PARM_DESC(invert, "invert data along each axis");
628 MODULE_AUTHOR("Robert Love");
629 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
630 MODULE_LICENSE("GPL v2");