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v4.6
  1/*
  2 * 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 <jj@chaosbits.net>
  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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 30
 31#include <linux/delay.h>
 32#include <linux/platform_device.h>
 33#include <linux/input-polldev.h>
 34#include <linux/kernel.h>
 35#include <linux/mutex.h>
 36#include <linux/module.h>
 37#include <linux/timer.h>
 38#include <linux/dmi.h>
 39#include <linux/jiffies.h>
 40#include <linux/io.h>
 41
 42#define HDAPS_LOW_PORT		0x1600	/* first port used by hdaps */
 43#define HDAPS_NR_PORTS		0x30	/* number of ports: 0x1600 - 0x162f */
 44
 45#define HDAPS_PORT_STATE	0x1611	/* device state */
 46#define HDAPS_PORT_YPOS		0x1612	/* y-axis position */
 47#define	HDAPS_PORT_XPOS		0x1614	/* x-axis position */
 48#define HDAPS_PORT_TEMP1	0x1616	/* device temperature, in Celsius */
 49#define HDAPS_PORT_YVAR		0x1617	/* y-axis variance (what is this?) */
 50#define HDAPS_PORT_XVAR		0x1619	/* x-axis variance (what is this?) */
 51#define HDAPS_PORT_TEMP2	0x161b	/* device temperature (again?) */
 52#define HDAPS_PORT_UNKNOWN	0x161c	/* what is this? */
 53#define HDAPS_PORT_KMACT	0x161d	/* keyboard or mouse activity */
 54
 55#define STATE_FRESH		0x50	/* accelerometer data is fresh */
 56
 57#define KEYBD_MASK		0x20	/* set if keyboard activity */
 58#define MOUSE_MASK		0x40	/* set if mouse activity */
 59#define KEYBD_ISSET(n)		(!! (n & KEYBD_MASK))	/* keyboard used? */
 60#define MOUSE_ISSET(n)		(!! (n & MOUSE_MASK))	/* mouse used? */
 61
 62#define INIT_TIMEOUT_MSECS	4000	/* wait up to 4s for device init ... */
 63#define INIT_WAIT_MSECS		200	/* ... in 200ms increments */
 64
 65#define HDAPS_POLL_INTERVAL	50	/* poll for input every 1/20s (50 ms)*/
 66#define HDAPS_INPUT_FUZZ	4	/* input event threshold */
 67#define HDAPS_INPUT_FLAT	4
 68
 69#define HDAPS_X_AXIS		(1 << 0)
 70#define HDAPS_Y_AXIS		(1 << 1)
 71#define HDAPS_BOTH_AXES		(HDAPS_X_AXIS | HDAPS_Y_AXIS)
 72
 73static struct platform_device *pdev;
 74static struct input_polled_dev *hdaps_idev;
 75static unsigned int hdaps_invert;
 76static u8 km_activity;
 77static int rest_x;
 78static int rest_y;
 79
 80static DEFINE_MUTEX(hdaps_mtx);
 81
 82/*
 83 * __get_latch - Get the value from a given port.  Callers must hold hdaps_mtx.
 84 */
 85static inline u8 __get_latch(u16 port)
 86{
 87	return inb(port) & 0xff;
 88}
 89
 90/*
 91 * __check_latch - Check a port latch for a given value.  Returns zero if the
 92 * port contains the given value.  Callers must hold hdaps_mtx.
 93 */
 94static inline int __check_latch(u16 port, u8 val)
 95{
 96	if (__get_latch(port) == val)
 97		return 0;
 98	return -EINVAL;
 99}
100
101/*
102 * __wait_latch - Wait up to 100us for a port latch to get a certain value,
103 * returning zero if the value is obtained.  Callers must hold hdaps_mtx.
104 */
105static int __wait_latch(u16 port, u8 val)
106{
107	unsigned int i;
108
109	for (i = 0; i < 20; i++) {
110		if (!__check_latch(port, val))
111			return 0;
112		udelay(5);
113	}
114
115	return -EIO;
116}
117
118/*
119 * __device_refresh - request a refresh from the accelerometer.  Does not wait
120 * for refresh to complete.  Callers must hold hdaps_mtx.
121 */
122static void __device_refresh(void)
123{
124	udelay(200);
125	if (inb(0x1604) != STATE_FRESH) {
126		outb(0x11, 0x1610);
127		outb(0x01, 0x161f);
128	}
129}
130
131/*
132 * __device_refresh_sync - request a synchronous refresh from the
133 * accelerometer.  We wait for the refresh to complete.  Returns zero if
134 * successful and nonzero on error.  Callers must hold hdaps_mtx.
135 */
136static int __device_refresh_sync(void)
137{
138	__device_refresh();
139	return __wait_latch(0x1604, STATE_FRESH);
140}
141
142/*
143 * __device_complete - indicate to the accelerometer that we are done reading
144 * data, and then initiate an async refresh.  Callers must hold hdaps_mtx.
145 */
146static inline void __device_complete(void)
147{
148	inb(0x161f);
149	inb(0x1604);
150	__device_refresh();
151}
152
153/*
154 * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
155 * the given pointer.  Returns zero on success or a negative error on failure.
156 * Can sleep.
157 */
158static int hdaps_readb_one(unsigned int port, u8 *val)
159{
160	int ret;
161
162	mutex_lock(&hdaps_mtx);
163
164	/* do a sync refresh -- we need to be sure that we read fresh data */
165	ret = __device_refresh_sync();
166	if (ret)
167		goto out;
168
169	*val = inb(port);
170	__device_complete();
171
172out:
173	mutex_unlock(&hdaps_mtx);
174	return ret;
175}
176
177/* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
178static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
179			     int *x, int *y)
180{
181	/* do a sync refresh -- we need to be sure that we read fresh data */
182	if (__device_refresh_sync())
183		return -EIO;
184
185	*y = inw(port2);
186	*x = inw(port1);
187	km_activity = inb(HDAPS_PORT_KMACT);
188	__device_complete();
189
190	/* hdaps_invert is a bitvector to negate the axes */
191	if (hdaps_invert & HDAPS_X_AXIS)
192		*x = -*x;
193	if (hdaps_invert & HDAPS_Y_AXIS)
194		*y = -*y;
195
196	return 0;
197}
198
199/*
200 * hdaps_read_pair - reads the values from a pair of ports, placing the values
201 * in the given pointers.  Returns zero on success.  Can sleep.
202 */
203static int hdaps_read_pair(unsigned int port1, unsigned int port2,
204			   int *val1, int *val2)
205{
206	int ret;
207
208	mutex_lock(&hdaps_mtx);
209	ret = __hdaps_read_pair(port1, port2, val1, val2);
210	mutex_unlock(&hdaps_mtx);
211
212	return ret;
213}
214
215/*
216 * hdaps_device_init - initialize the accelerometer.  Returns zero on success
217 * and negative error code on failure.  Can sleep.
218 */
219static int hdaps_device_init(void)
220{
221	int total, ret = -ENXIO;
222
223	mutex_lock(&hdaps_mtx);
224
225	outb(0x13, 0x1610);
226	outb(0x01, 0x161f);
227	if (__wait_latch(0x161f, 0x00))
228		goto out;
229
230	/*
231	 * Most ThinkPads return 0x01.
232	 *
233	 * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
234	 * have "inverted" axises.
235	 *
236	 * The 0x02 value occurs when the chip has been previously initialized.
237	 */
238	if (__check_latch(0x1611, 0x03) &&
239		     __check_latch(0x1611, 0x02) &&
240		     __check_latch(0x1611, 0x01))
241		goto out;
242
243	printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x)\n",
244	       __get_latch(0x1611));
245
246	outb(0x17, 0x1610);
247	outb(0x81, 0x1611);
248	outb(0x01, 0x161f);
249	if (__wait_latch(0x161f, 0x00))
250		goto out;
251	if (__wait_latch(0x1611, 0x00))
252		goto out;
253	if (__wait_latch(0x1612, 0x60))
254		goto out;
255	if (__wait_latch(0x1613, 0x00))
256		goto out;
257	outb(0x14, 0x1610);
258	outb(0x01, 0x1611);
259	outb(0x01, 0x161f);
260	if (__wait_latch(0x161f, 0x00))
261		goto out;
262	outb(0x10, 0x1610);
263	outb(0xc8, 0x1611);
264	outb(0x00, 0x1612);
265	outb(0x02, 0x1613);
266	outb(0x01, 0x161f);
267	if (__wait_latch(0x161f, 0x00))
268		goto out;
269	if (__device_refresh_sync())
270		goto out;
271	if (__wait_latch(0x1611, 0x00))
272		goto out;
273
274	/* we have done our dance, now let's wait for the applause */
275	for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
276		int x, y;
277
278		/* a read of the device helps push it into action */
279		__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
280		if (!__wait_latch(0x1611, 0x02)) {
281			ret = 0;
282			break;
283		}
284
285		msleep(INIT_WAIT_MSECS);
286	}
287
288out:
289	mutex_unlock(&hdaps_mtx);
290	return ret;
291}
292
293
294/* Device model stuff */
295
296static int hdaps_probe(struct platform_device *dev)
297{
298	int ret;
299
300	ret = hdaps_device_init();
301	if (ret)
302		return ret;
303
304	pr_info("device successfully initialized\n");
305	return 0;
306}
307
308#ifdef CONFIG_PM_SLEEP
309static int hdaps_resume(struct device *dev)
310{
311	return hdaps_device_init();
312}
313#endif
314
315static SIMPLE_DEV_PM_OPS(hdaps_pm, NULL, hdaps_resume);
316
317static struct platform_driver hdaps_driver = {
318	.probe = hdaps_probe,
 
319	.driver	= {
320		.name = "hdaps",
321		.pm = &hdaps_pm,
322	},
323};
324
325/*
326 * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_mtx.
327 */
328static void hdaps_calibrate(void)
329{
330	__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
331}
332
333static void hdaps_mousedev_poll(struct input_polled_dev *dev)
334{
335	struct input_dev *input_dev = dev->input;
336	int x, y;
337
338	mutex_lock(&hdaps_mtx);
339
340	if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
341		goto out;
342
343	input_report_abs(input_dev, ABS_X, x - rest_x);
344	input_report_abs(input_dev, ABS_Y, y - rest_y);
345	input_sync(input_dev);
346
347out:
348	mutex_unlock(&hdaps_mtx);
349}
350
351
352/* Sysfs Files */
353
354static ssize_t hdaps_position_show(struct device *dev,
355				   struct device_attribute *attr, char *buf)
356{
357	int ret, x, y;
358
359	ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
360	if (ret)
361		return ret;
362
363	return sprintf(buf, "(%d,%d)\n", x, y);
364}
365
366static ssize_t hdaps_variance_show(struct device *dev,
367				   struct device_attribute *attr, char *buf)
368{
369	int ret, x, y;
370
371	ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
372	if (ret)
373		return ret;
374
375	return sprintf(buf, "(%d,%d)\n", x, y);
376}
377
378static ssize_t hdaps_temp1_show(struct device *dev,
379				struct device_attribute *attr, char *buf)
380{
381	u8 uninitialized_var(temp);
382	int ret;
383
384	ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
385	if (ret)
386		return ret;
387
388	return sprintf(buf, "%u\n", temp);
389}
390
391static ssize_t hdaps_temp2_show(struct device *dev,
392				struct device_attribute *attr, char *buf)
393{
394	u8 uninitialized_var(temp);
395	int ret;
396
397	ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
398	if (ret)
399		return ret;
400
401	return sprintf(buf, "%u\n", temp);
402}
403
404static ssize_t hdaps_keyboard_activity_show(struct device *dev,
405					    struct device_attribute *attr,
406					    char *buf)
407{
408	return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
409}
410
411static ssize_t hdaps_mouse_activity_show(struct device *dev,
412					 struct device_attribute *attr,
413					 char *buf)
414{
415	return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
416}
417
418static ssize_t hdaps_calibrate_show(struct device *dev,
419				    struct device_attribute *attr, char *buf)
420{
421	return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
422}
423
424static ssize_t hdaps_calibrate_store(struct device *dev,
425				     struct device_attribute *attr,
426				     const char *buf, size_t count)
427{
428	mutex_lock(&hdaps_mtx);
429	hdaps_calibrate();
430	mutex_unlock(&hdaps_mtx);
431
432	return count;
433}
434
435static ssize_t hdaps_invert_show(struct device *dev,
436				 struct device_attribute *attr, char *buf)
437{
438	return sprintf(buf, "%u\n", hdaps_invert);
439}
440
441static ssize_t hdaps_invert_store(struct device *dev,
442				  struct device_attribute *attr,
443				  const char *buf, size_t count)
444{
445	int invert;
446
447	if (sscanf(buf, "%d", &invert) != 1 ||
448	    invert < 0 || invert > HDAPS_BOTH_AXES)
449		return -EINVAL;
450
451	hdaps_invert = invert;
452	hdaps_calibrate();
453
454	return count;
455}
456
457static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
458static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
459static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
460static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
461static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
462static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
463static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
464static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
465
466static struct attribute *hdaps_attributes[] = {
467	&dev_attr_position.attr,
468	&dev_attr_variance.attr,
469	&dev_attr_temp1.attr,
470	&dev_attr_temp2.attr,
471	&dev_attr_keyboard_activity.attr,
472	&dev_attr_mouse_activity.attr,
473	&dev_attr_calibrate.attr,
474	&dev_attr_invert.attr,
475	NULL,
476};
477
478static struct attribute_group hdaps_attribute_group = {
479	.attrs = hdaps_attributes,
480};
481
482
483/* Module stuff */
484
485/* hdaps_dmi_match - found a match.  return one, short-circuiting the hunt. */
486static int __init hdaps_dmi_match(const struct dmi_system_id *id)
487{
488	pr_info("%s detected\n", id->ident);
489	return 1;
490}
491
492/* hdaps_dmi_match_invert - found an inverted match. */
493static int __init hdaps_dmi_match_invert(const struct dmi_system_id *id)
494{
495	hdaps_invert = (unsigned long)id->driver_data;
496	pr_info("inverting axis (%u) readings\n", hdaps_invert);
497	return hdaps_dmi_match(id);
498}
499
500#define HDAPS_DMI_MATCH_INVERT(vendor, model, axes) {	\
501	.ident = vendor " " model,			\
502	.callback = hdaps_dmi_match_invert,		\
503	.driver_data = (void *)axes,			\
504	.matches = {					\
505		DMI_MATCH(DMI_BOARD_VENDOR, vendor),	\
506		DMI_MATCH(DMI_PRODUCT_VERSION, model)	\
507	}						\
508}
509
510#define HDAPS_DMI_MATCH_NORMAL(vendor, model)		\
511	HDAPS_DMI_MATCH_INVERT(vendor, model, 0)
512
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. */
517static struct dmi_system_id __initdata hdaps_whitelist[] = {
518	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad R50p", HDAPS_BOTH_AXES),
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("LENOVO", "ThinkPad R61i", HDAPS_BOTH_AXES),
523	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61", HDAPS_BOTH_AXES),
524	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T41p", HDAPS_BOTH_AXES),
525	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T41"),
526	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T42p", HDAPS_BOTH_AXES),
527	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T42"),
528	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T43"),
529	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T400", HDAPS_BOTH_AXES),
530	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T60", HDAPS_BOTH_AXES),
531	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61p", HDAPS_BOTH_AXES),
532	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61", HDAPS_BOTH_AXES),
533	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X40"),
534	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad X41", HDAPS_Y_AXIS),
535	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X60", HDAPS_BOTH_AXES),
536	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61s", HDAPS_BOTH_AXES),
537	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61", HDAPS_BOTH_AXES),
538	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad Z60m"),
539	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61m", HDAPS_BOTH_AXES),
540	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61p", HDAPS_BOTH_AXES),
541	{ .ident = NULL }
542};
543
544static int __init hdaps_init(void)
545{
546	struct input_dev *idev;
547	int ret;
548
549	if (!dmi_check_system(hdaps_whitelist)) {
550		pr_warn("supported laptop not found!\n");
551		ret = -ENODEV;
552		goto out;
553	}
554
555	if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
556		ret = -ENXIO;
557		goto out;
558	}
559
560	ret = platform_driver_register(&hdaps_driver);
561	if (ret)
562		goto out_region;
563
564	pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
565	if (IS_ERR(pdev)) {
566		ret = PTR_ERR(pdev);
567		goto out_driver;
568	}
569
570	ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
571	if (ret)
572		goto out_device;
573
574	hdaps_idev = input_allocate_polled_device();
575	if (!hdaps_idev) {
576		ret = -ENOMEM;
577		goto out_group;
578	}
579
580	hdaps_idev->poll = hdaps_mousedev_poll;
581	hdaps_idev->poll_interval = HDAPS_POLL_INTERVAL;
582
583	/* initial calibrate for the input device */
584	hdaps_calibrate();
585
586	/* initialize the input class */
587	idev = hdaps_idev->input;
588	idev->name = "hdaps";
589	idev->phys = "isa1600/input0";
590	idev->id.bustype = BUS_ISA;
591	idev->dev.parent = &pdev->dev;
592	idev->evbit[0] = BIT_MASK(EV_ABS);
593	input_set_abs_params(idev, ABS_X,
594			-256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
595	input_set_abs_params(idev, ABS_Y,
596			-256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
597
598	ret = input_register_polled_device(hdaps_idev);
599	if (ret)
600		goto out_idev;
601
602	pr_info("driver successfully loaded\n");
603	return 0;
604
605out_idev:
606	input_free_polled_device(hdaps_idev);
607out_group:
608	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
609out_device:
610	platform_device_unregister(pdev);
611out_driver:
612	platform_driver_unregister(&hdaps_driver);
613out_region:
614	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
615out:
616	pr_warn("driver init failed (ret=%d)!\n", ret);
617	return ret;
618}
619
620static void __exit hdaps_exit(void)
621{
622	input_unregister_polled_device(hdaps_idev);
623	input_free_polled_device(hdaps_idev);
624	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
625	platform_device_unregister(pdev);
626	platform_driver_unregister(&hdaps_driver);
627	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
628
629	pr_info("driver unloaded\n");
630}
631
632module_init(hdaps_init);
633module_exit(hdaps_exit);
634
635module_param_named(invert, hdaps_invert, int, 0);
636MODULE_PARM_DESC(invert, "invert data along each axis. 1 invert x-axis, "
637		 "2 invert y-axis, 3 invert both axes.");
638
639MODULE_AUTHOR("Robert Love");
640MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
641MODULE_LICENSE("GPL v2");
v3.1
  1/*
  2 * 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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 30
 31#include <linux/delay.h>
 32#include <linux/platform_device.h>
 33#include <linux/input-polldev.h>
 34#include <linux/kernel.h>
 35#include <linux/mutex.h>
 36#include <linux/module.h>
 37#include <linux/timer.h>
 38#include <linux/dmi.h>
 39#include <linux/jiffies.h>
 40#include <linux/io.h>
 41
 42#define HDAPS_LOW_PORT		0x1600	/* first port used by hdaps */
 43#define HDAPS_NR_PORTS		0x30	/* number of ports: 0x1600 - 0x162f */
 44
 45#define HDAPS_PORT_STATE	0x1611	/* device state */
 46#define HDAPS_PORT_YPOS		0x1612	/* y-axis position */
 47#define	HDAPS_PORT_XPOS		0x1614	/* x-axis position */
 48#define HDAPS_PORT_TEMP1	0x1616	/* device temperature, in Celsius */
 49#define HDAPS_PORT_YVAR		0x1617	/* y-axis variance (what is this?) */
 50#define HDAPS_PORT_XVAR		0x1619	/* x-axis variance (what is this?) */
 51#define HDAPS_PORT_TEMP2	0x161b	/* device temperature (again?) */
 52#define HDAPS_PORT_UNKNOWN	0x161c	/* what is this? */
 53#define HDAPS_PORT_KMACT	0x161d	/* keyboard or mouse activity */
 54
 55#define STATE_FRESH		0x50	/* accelerometer data is fresh */
 56
 57#define KEYBD_MASK		0x20	/* set if keyboard activity */
 58#define MOUSE_MASK		0x40	/* set if mouse activity */
 59#define KEYBD_ISSET(n)		(!! (n & KEYBD_MASK))	/* keyboard used? */
 60#define MOUSE_ISSET(n)		(!! (n & MOUSE_MASK))	/* mouse used? */
 61
 62#define INIT_TIMEOUT_MSECS	4000	/* wait up to 4s for device init ... */
 63#define INIT_WAIT_MSECS		200	/* ... in 200ms increments */
 64
 65#define HDAPS_POLL_INTERVAL	50	/* poll for input every 1/20s (50 ms)*/
 66#define HDAPS_INPUT_FUZZ	4	/* input event threshold */
 67#define HDAPS_INPUT_FLAT	4
 68
 69#define HDAPS_X_AXIS		(1 << 0)
 70#define HDAPS_Y_AXIS		(1 << 1)
 71#define HDAPS_BOTH_AXES		(HDAPS_X_AXIS | HDAPS_Y_AXIS)
 72
 73static struct platform_device *pdev;
 74static struct input_polled_dev *hdaps_idev;
 75static unsigned int hdaps_invert;
 76static u8 km_activity;
 77static int rest_x;
 78static int rest_y;
 79
 80static DEFINE_MUTEX(hdaps_mtx);
 81
 82/*
 83 * __get_latch - Get the value from a given port.  Callers must hold hdaps_mtx.
 84 */
 85static inline u8 __get_latch(u16 port)
 86{
 87	return inb(port) & 0xff;
 88}
 89
 90/*
 91 * __check_latch - Check a port latch for a given value.  Returns zero if the
 92 * port contains the given value.  Callers must hold hdaps_mtx.
 93 */
 94static inline int __check_latch(u16 port, u8 val)
 95{
 96	if (__get_latch(port) == val)
 97		return 0;
 98	return -EINVAL;
 99}
100
101/*
102 * __wait_latch - Wait up to 100us for a port latch to get a certain value,
103 * returning zero if the value is obtained.  Callers must hold hdaps_mtx.
104 */
105static int __wait_latch(u16 port, u8 val)
106{
107	unsigned int i;
108
109	for (i = 0; i < 20; i++) {
110		if (!__check_latch(port, val))
111			return 0;
112		udelay(5);
113	}
114
115	return -EIO;
116}
117
118/*
119 * __device_refresh - request a refresh from the accelerometer.  Does not wait
120 * for refresh to complete.  Callers must hold hdaps_mtx.
121 */
122static void __device_refresh(void)
123{
124	udelay(200);
125	if (inb(0x1604) != STATE_FRESH) {
126		outb(0x11, 0x1610);
127		outb(0x01, 0x161f);
128	}
129}
130
131/*
132 * __device_refresh_sync - request a synchronous refresh from the
133 * accelerometer.  We wait for the refresh to complete.  Returns zero if
134 * successful and nonzero on error.  Callers must hold hdaps_mtx.
135 */
136static int __device_refresh_sync(void)
137{
138	__device_refresh();
139	return __wait_latch(0x1604, STATE_FRESH);
140}
141
142/*
143 * __device_complete - indicate to the accelerometer that we are done reading
144 * data, and then initiate an async refresh.  Callers must hold hdaps_mtx.
145 */
146static inline void __device_complete(void)
147{
148	inb(0x161f);
149	inb(0x1604);
150	__device_refresh();
151}
152
153/*
154 * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
155 * the given pointer.  Returns zero on success or a negative error on failure.
156 * Can sleep.
157 */
158static int hdaps_readb_one(unsigned int port, u8 *val)
159{
160	int ret;
161
162	mutex_lock(&hdaps_mtx);
163
164	/* do a sync refresh -- we need to be sure that we read fresh data */
165	ret = __device_refresh_sync();
166	if (ret)
167		goto out;
168
169	*val = inb(port);
170	__device_complete();
171
172out:
173	mutex_unlock(&hdaps_mtx);
174	return ret;
175}
176
177/* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
178static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
179			     int *x, int *y)
180{
181	/* do a sync refresh -- we need to be sure that we read fresh data */
182	if (__device_refresh_sync())
183		return -EIO;
184
185	*y = inw(port2);
186	*x = inw(port1);
187	km_activity = inb(HDAPS_PORT_KMACT);
188	__device_complete();
189
190	/* hdaps_invert is a bitvector to negate the axes */
191	if (hdaps_invert & HDAPS_X_AXIS)
192		*x = -*x;
193	if (hdaps_invert & HDAPS_Y_AXIS)
194		*y = -*y;
195
196	return 0;
197}
198
199/*
200 * hdaps_read_pair - reads the values from a pair of ports, placing the values
201 * in the given pointers.  Returns zero on success.  Can sleep.
202 */
203static int hdaps_read_pair(unsigned int port1, unsigned int port2,
204			   int *val1, int *val2)
205{
206	int ret;
207
208	mutex_lock(&hdaps_mtx);
209	ret = __hdaps_read_pair(port1, port2, val1, val2);
210	mutex_unlock(&hdaps_mtx);
211
212	return ret;
213}
214
215/*
216 * hdaps_device_init - initialize the accelerometer.  Returns zero on success
217 * and negative error code on failure.  Can sleep.
218 */
219static int hdaps_device_init(void)
220{
221	int total, ret = -ENXIO;
222
223	mutex_lock(&hdaps_mtx);
224
225	outb(0x13, 0x1610);
226	outb(0x01, 0x161f);
227	if (__wait_latch(0x161f, 0x00))
228		goto out;
229
230	/*
231	 * Most ThinkPads return 0x01.
232	 *
233	 * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
234	 * have "inverted" axises.
235	 *
236	 * The 0x02 value occurs when the chip has been previously initialized.
237	 */
238	if (__check_latch(0x1611, 0x03) &&
239		     __check_latch(0x1611, 0x02) &&
240		     __check_latch(0x1611, 0x01))
241		goto out;
242
243	printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x)\n",
244	       __get_latch(0x1611));
245
246	outb(0x17, 0x1610);
247	outb(0x81, 0x1611);
248	outb(0x01, 0x161f);
249	if (__wait_latch(0x161f, 0x00))
250		goto out;
251	if (__wait_latch(0x1611, 0x00))
252		goto out;
253	if (__wait_latch(0x1612, 0x60))
254		goto out;
255	if (__wait_latch(0x1613, 0x00))
256		goto out;
257	outb(0x14, 0x1610);
258	outb(0x01, 0x1611);
259	outb(0x01, 0x161f);
260	if (__wait_latch(0x161f, 0x00))
261		goto out;
262	outb(0x10, 0x1610);
263	outb(0xc8, 0x1611);
264	outb(0x00, 0x1612);
265	outb(0x02, 0x1613);
266	outb(0x01, 0x161f);
267	if (__wait_latch(0x161f, 0x00))
268		goto out;
269	if (__device_refresh_sync())
270		goto out;
271	if (__wait_latch(0x1611, 0x00))
272		goto out;
273
274	/* we have done our dance, now let's wait for the applause */
275	for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
276		int x, y;
277
278		/* a read of the device helps push it into action */
279		__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
280		if (!__wait_latch(0x1611, 0x02)) {
281			ret = 0;
282			break;
283		}
284
285		msleep(INIT_WAIT_MSECS);
286	}
287
288out:
289	mutex_unlock(&hdaps_mtx);
290	return ret;
291}
292
293
294/* Device model stuff */
295
296static int hdaps_probe(struct platform_device *dev)
297{
298	int ret;
299
300	ret = hdaps_device_init();
301	if (ret)
302		return ret;
303
304	pr_info("device successfully initialized\n");
305	return 0;
306}
307
308static int hdaps_resume(struct platform_device *dev)
 
309{
310	return hdaps_device_init();
311}
 
 
 
312
313static struct platform_driver hdaps_driver = {
314	.probe = hdaps_probe,
315	.resume = hdaps_resume,
316	.driver	= {
317		.name = "hdaps",
318		.owner = THIS_MODULE,
319	},
320};
321
322/*
323 * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_mtx.
324 */
325static void hdaps_calibrate(void)
326{
327	__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
328}
329
330static void hdaps_mousedev_poll(struct input_polled_dev *dev)
331{
332	struct input_dev *input_dev = dev->input;
333	int x, y;
334
335	mutex_lock(&hdaps_mtx);
336
337	if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
338		goto out;
339
340	input_report_abs(input_dev, ABS_X, x - rest_x);
341	input_report_abs(input_dev, ABS_Y, y - rest_y);
342	input_sync(input_dev);
343
344out:
345	mutex_unlock(&hdaps_mtx);
346}
347
348
349/* Sysfs Files */
350
351static ssize_t hdaps_position_show(struct device *dev,
352				   struct device_attribute *attr, char *buf)
353{
354	int ret, x, y;
355
356	ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
357	if (ret)
358		return ret;
359
360	return sprintf(buf, "(%d,%d)\n", x, y);
361}
362
363static ssize_t hdaps_variance_show(struct device *dev,
364				   struct device_attribute *attr, char *buf)
365{
366	int ret, x, y;
367
368	ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
369	if (ret)
370		return ret;
371
372	return sprintf(buf, "(%d,%d)\n", x, y);
373}
374
375static ssize_t hdaps_temp1_show(struct device *dev,
376				struct device_attribute *attr, char *buf)
377{
378	u8 temp;
379	int ret;
380
381	ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
382	if (ret < 0)
383		return ret;
384
385	return sprintf(buf, "%u\n", temp);
386}
387
388static ssize_t hdaps_temp2_show(struct device *dev,
389				struct device_attribute *attr, char *buf)
390{
391	u8 temp;
392	int ret;
393
394	ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
395	if (ret < 0)
396		return ret;
397
398	return sprintf(buf, "%u\n", temp);
399}
400
401static ssize_t hdaps_keyboard_activity_show(struct device *dev,
402					    struct device_attribute *attr,
403					    char *buf)
404{
405	return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
406}
407
408static ssize_t hdaps_mouse_activity_show(struct device *dev,
409					 struct device_attribute *attr,
410					 char *buf)
411{
412	return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
413}
414
415static ssize_t hdaps_calibrate_show(struct device *dev,
416				    struct device_attribute *attr, char *buf)
417{
418	return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
419}
420
421static ssize_t hdaps_calibrate_store(struct device *dev,
422				     struct device_attribute *attr,
423				     const char *buf, size_t count)
424{
425	mutex_lock(&hdaps_mtx);
426	hdaps_calibrate();
427	mutex_unlock(&hdaps_mtx);
428
429	return count;
430}
431
432static ssize_t hdaps_invert_show(struct device *dev,
433				 struct device_attribute *attr, char *buf)
434{
435	return sprintf(buf, "%u\n", hdaps_invert);
436}
437
438static ssize_t hdaps_invert_store(struct device *dev,
439				  struct device_attribute *attr,
440				  const char *buf, size_t count)
441{
442	int invert;
443
444	if (sscanf(buf, "%d", &invert) != 1 ||
445	    invert < 0 || invert > HDAPS_BOTH_AXES)
446		return -EINVAL;
447
448	hdaps_invert = invert;
449	hdaps_calibrate();
450
451	return count;
452}
453
454static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
455static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
456static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
457static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
458static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
459static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
460static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
461static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
462
463static struct attribute *hdaps_attributes[] = {
464	&dev_attr_position.attr,
465	&dev_attr_variance.attr,
466	&dev_attr_temp1.attr,
467	&dev_attr_temp2.attr,
468	&dev_attr_keyboard_activity.attr,
469	&dev_attr_mouse_activity.attr,
470	&dev_attr_calibrate.attr,
471	&dev_attr_invert.attr,
472	NULL,
473};
474
475static struct attribute_group hdaps_attribute_group = {
476	.attrs = hdaps_attributes,
477};
478
479
480/* Module stuff */
481
482/* hdaps_dmi_match - found a match.  return one, short-circuiting the hunt. */
483static int __init hdaps_dmi_match(const struct dmi_system_id *id)
484{
485	pr_info("%s detected\n", id->ident);
486	return 1;
487}
488
489/* hdaps_dmi_match_invert - found an inverted match. */
490static int __init hdaps_dmi_match_invert(const struct dmi_system_id *id)
491{
492	hdaps_invert = (unsigned long)id->driver_data;
493	pr_info("inverting axis (%u) readings\n", hdaps_invert);
494	return hdaps_dmi_match(id);
495}
496
497#define HDAPS_DMI_MATCH_INVERT(vendor, model, axes) {	\
498	.ident = vendor " " model,			\
499	.callback = hdaps_dmi_match_invert,		\
500	.driver_data = (void *)axes,			\
501	.matches = {					\
502		DMI_MATCH(DMI_BOARD_VENDOR, vendor),	\
503		DMI_MATCH(DMI_PRODUCT_VERSION, model)	\
504	}						\
505}
506
507#define HDAPS_DMI_MATCH_NORMAL(vendor, model)		\
508	HDAPS_DMI_MATCH_INVERT(vendor, model, 0)
509
510/* Note that HDAPS_DMI_MATCH_NORMAL("ThinkPad T42") would match
511   "ThinkPad T42p", so the order of the entries matters.
512   If your ThinkPad is not recognized, please update to latest
513   BIOS. This is especially the case for some R52 ThinkPads. */
514static struct dmi_system_id __initdata hdaps_whitelist[] = {
515	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad R50p", HDAPS_BOTH_AXES),
516	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R50"),
517	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R51"),
518	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R52"),
519	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61i", HDAPS_BOTH_AXES),
520	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61", HDAPS_BOTH_AXES),
521	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T41p", HDAPS_BOTH_AXES),
522	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T41"),
523	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T42p", HDAPS_BOTH_AXES),
524	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T42"),
525	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T43"),
526	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T400", HDAPS_BOTH_AXES),
527	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T60", HDAPS_BOTH_AXES),
528	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61p", HDAPS_BOTH_AXES),
529	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61", HDAPS_BOTH_AXES),
530	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X40"),
531	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad X41", HDAPS_Y_AXIS),
532	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X60", HDAPS_BOTH_AXES),
533	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61s", HDAPS_BOTH_AXES),
534	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61", HDAPS_BOTH_AXES),
535	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad Z60m"),
536	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61m", HDAPS_BOTH_AXES),
537	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61p", HDAPS_BOTH_AXES),
538	{ .ident = NULL }
539};
540
541static int __init hdaps_init(void)
542{
543	struct input_dev *idev;
544	int ret;
545
546	if (!dmi_check_system(hdaps_whitelist)) {
547		pr_warn("supported laptop not found!\n");
548		ret = -ENODEV;
549		goto out;
550	}
551
552	if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
553		ret = -ENXIO;
554		goto out;
555	}
556
557	ret = platform_driver_register(&hdaps_driver);
558	if (ret)
559		goto out_region;
560
561	pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
562	if (IS_ERR(pdev)) {
563		ret = PTR_ERR(pdev);
564		goto out_driver;
565	}
566
567	ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
568	if (ret)
569		goto out_device;
570
571	hdaps_idev = input_allocate_polled_device();
572	if (!hdaps_idev) {
573		ret = -ENOMEM;
574		goto out_group;
575	}
576
577	hdaps_idev->poll = hdaps_mousedev_poll;
578	hdaps_idev->poll_interval = HDAPS_POLL_INTERVAL;
579
580	/* initial calibrate for the input device */
581	hdaps_calibrate();
582
583	/* initialize the input class */
584	idev = hdaps_idev->input;
585	idev->name = "hdaps";
586	idev->phys = "isa1600/input0";
587	idev->id.bustype = BUS_ISA;
588	idev->dev.parent = &pdev->dev;
589	idev->evbit[0] = BIT_MASK(EV_ABS);
590	input_set_abs_params(idev, ABS_X,
591			-256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
592	input_set_abs_params(idev, ABS_Y,
593			-256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
594
595	ret = input_register_polled_device(hdaps_idev);
596	if (ret)
597		goto out_idev;
598
599	pr_info("driver successfully loaded\n");
600	return 0;
601
602out_idev:
603	input_free_polled_device(hdaps_idev);
604out_group:
605	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
606out_device:
607	platform_device_unregister(pdev);
608out_driver:
609	platform_driver_unregister(&hdaps_driver);
610out_region:
611	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
612out:
613	pr_warn("driver init failed (ret=%d)!\n", ret);
614	return ret;
615}
616
617static void __exit hdaps_exit(void)
618{
619	input_unregister_polled_device(hdaps_idev);
620	input_free_polled_device(hdaps_idev);
621	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
622	platform_device_unregister(pdev);
623	platform_driver_unregister(&hdaps_driver);
624	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
625
626	pr_info("driver unloaded\n");
627}
628
629module_init(hdaps_init);
630module_exit(hdaps_exit);
631
632module_param_named(invert, hdaps_invert, int, 0);
633MODULE_PARM_DESC(invert, "invert data along each axis. 1 invert x-axis, "
634		 "2 invert y-axis, 3 invert both axes.");
635
636MODULE_AUTHOR("Robert Love");
637MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
638MODULE_LICENSE("GPL v2");