1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * hdaps.c - driver for IBM's Hard Drive Active Protection System
4  *
5  * Copyright (C) 2005 Robert Love <rml@novell.com>
6  * Copyright (C) 2005 Jesper Juhl <jj@chaosbits.net>
7  *
8  * The HardDisk Active Protection System (hdaps) is present in IBM ThinkPads
9  * starting with the R40, T41, and X40.  It provides a basic two-axis
10  * accelerometer and other data, such as the device's temperature.
11  *
12  * This driver is based on the document by Mark A. Smith available at
13  * http://www.almaden.ibm.com/cs/people/marksmith/tpaps.html and a lot of trial
14  * and error.
15  */
16 
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 
19 #include <linux/delay.h>
20 #include <linux/platform_device.h>
21 #include <linux/input.h>
22 #include <linux/kernel.h>
23 #include <linux/mutex.h>
24 #include <linux/module.h>
25 #include <linux/timer.h>
26 #include <linux/dmi.h>
27 #include <linux/jiffies.h>
28 #include <linux/io.h>
29 
30 #define HDAPS_LOW_PORT		0x1600	/* first port used by hdaps */
31 #define HDAPS_NR_PORTS		0x30	/* number of ports: 0x1600 - 0x162f */
32 
33 #define HDAPS_PORT_STATE	0x1611	/* device state */
34 #define HDAPS_PORT_YPOS		0x1612	/* y-axis position */
35 #define	HDAPS_PORT_XPOS		0x1614	/* x-axis position */
36 #define HDAPS_PORT_TEMP1	0x1616	/* device temperature, in Celsius */
37 #define HDAPS_PORT_YVAR		0x1617	/* y-axis variance (what is this?) */
38 #define HDAPS_PORT_XVAR		0x1619	/* x-axis variance (what is this?) */
39 #define HDAPS_PORT_TEMP2	0x161b	/* device temperature (again?) */
40 #define HDAPS_PORT_UNKNOWN	0x161c	/* what is this? */
41 #define HDAPS_PORT_KMACT	0x161d	/* keyboard or mouse activity */
42 
43 #define STATE_FRESH		0x50	/* accelerometer data is fresh */
44 
45 #define KEYBD_MASK		0x20	/* set if keyboard activity */
46 #define MOUSE_MASK		0x40	/* set if mouse activity */
47 #define KEYBD_ISSET(n)		(!! (n & KEYBD_MASK))	/* keyboard used? */
48 #define MOUSE_ISSET(n)		(!! (n & MOUSE_MASK))	/* mouse used? */
49 
50 #define INIT_TIMEOUT_MSECS	4000	/* wait up to 4s for device init ... */
51 #define INIT_WAIT_MSECS		200	/* ... in 200ms increments */
52 
53 #define HDAPS_POLL_INTERVAL	50	/* poll for input every 1/20s (50 ms)*/
54 #define HDAPS_INPUT_FUZZ	4	/* input event threshold */
55 #define HDAPS_INPUT_FLAT	4
56 
57 #define HDAPS_X_AXIS		(1 << 0)
58 #define HDAPS_Y_AXIS		(1 << 1)
59 #define HDAPS_BOTH_AXES		(HDAPS_X_AXIS | HDAPS_Y_AXIS)
60 
61 static struct platform_device *pdev;
62 static struct input_dev *hdaps_idev;
63 static unsigned int hdaps_invert;
64 static u8 km_activity;
65 static int rest_x;
66 static int rest_y;
67 
68 static DEFINE_MUTEX(hdaps_mtx);
69 
70 /*
71  * __get_latch - Get the value from a given port.  Callers must hold hdaps_mtx.
72  */
__get_latch(u16 port)73 static inline u8 __get_latch(u16 port)
74 {
75 	return inb(port) & 0xff;
76 }
77 
78 /*
79  * __check_latch - Check a port latch for a given value.  Returns zero if the
80  * port contains the given value.  Callers must hold hdaps_mtx.
81  */
__check_latch(u16 port,u8 val)82 static inline int __check_latch(u16 port, u8 val)
83 {
84 	if (__get_latch(port) == val)
85 		return 0;
86 	return -EINVAL;
87 }
88 
89 /*
90  * __wait_latch - Wait up to 100us for a port latch to get a certain value,
91  * returning zero if the value is obtained.  Callers must hold hdaps_mtx.
92  */
__wait_latch(u16 port,u8 val)93 static int __wait_latch(u16 port, u8 val)
94 {
95 	unsigned int i;
96 
97 	for (i = 0; i < 20; i++) {
98 		if (!__check_latch(port, val))
99 			return 0;
100 		udelay(5);
101 	}
102 
103 	return -EIO;
104 }
105 
106 /*
107  * __device_refresh - request a refresh from the accelerometer.  Does not wait
108  * for refresh to complete.  Callers must hold hdaps_mtx.
109  */
__device_refresh(void)110 static void __device_refresh(void)
111 {
112 	udelay(200);
113 	if (inb(0x1604) != STATE_FRESH) {
114 		outb(0x11, 0x1610);
115 		outb(0x01, 0x161f);
116 	}
117 }
118 
119 /*
120  * __device_refresh_sync - request a synchronous refresh from the
121  * accelerometer.  We wait for the refresh to complete.  Returns zero if
122  * successful and nonzero on error.  Callers must hold hdaps_mtx.
123  */
__device_refresh_sync(void)124 static int __device_refresh_sync(void)
125 {
126 	__device_refresh();
127 	return __wait_latch(0x1604, STATE_FRESH);
128 }
129 
130 /*
131  * __device_complete - indicate to the accelerometer that we are done reading
132  * data, and then initiate an async refresh.  Callers must hold hdaps_mtx.
133  */
__device_complete(void)134 static inline void __device_complete(void)
135 {
136 	inb(0x161f);
137 	inb(0x1604);
138 	__device_refresh();
139 }
140 
141 /*
142  * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
143  * the given pointer.  Returns zero on success or a negative error on failure.
144  * Can sleep.
145  */
hdaps_readb_one(unsigned int port,u8 * val)146 static int hdaps_readb_one(unsigned int port, u8 *val)
147 {
148 	int ret;
149 
150 	mutex_lock(&hdaps_mtx);
151 
152 	/* do a sync refresh -- we need to be sure that we read fresh data */
153 	ret = __device_refresh_sync();
154 	if (ret)
155 		goto out;
156 
157 	*val = inb(port);
158 	__device_complete();
159 
160 out:
161 	mutex_unlock(&hdaps_mtx);
162 	return ret;
163 }
164 
165 /* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
__hdaps_read_pair(unsigned int port1,unsigned int port2,int * x,int * y)166 static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
167 			     int *x, int *y)
168 {
169 	/* do a sync refresh -- we need to be sure that we read fresh data */
170 	if (__device_refresh_sync())
171 		return -EIO;
172 
173 	*y = inw(port2);
174 	*x = inw(port1);
175 	km_activity = inb(HDAPS_PORT_KMACT);
176 	__device_complete();
177 
178 	/* hdaps_invert is a bitvector to negate the axes */
179 	if (hdaps_invert & HDAPS_X_AXIS)
180 		*x = -*x;
181 	if (hdaps_invert & HDAPS_Y_AXIS)
182 		*y = -*y;
183 
184 	return 0;
185 }
186 
187 /*
188  * hdaps_read_pair - reads the values from a pair of ports, placing the values
189  * in the given pointers.  Returns zero on success.  Can sleep.
190  */
hdaps_read_pair(unsigned int port1,unsigned int port2,int * val1,int * val2)191 static int hdaps_read_pair(unsigned int port1, unsigned int port2,
192 			   int *val1, int *val2)
193 {
194 	int ret;
195 
196 	mutex_lock(&hdaps_mtx);
197 	ret = __hdaps_read_pair(port1, port2, val1, val2);
198 	mutex_unlock(&hdaps_mtx);
199 
200 	return ret;
201 }
202 
203 /*
204  * hdaps_device_init - initialize the accelerometer.  Returns zero on success
205  * and negative error code on failure.  Can sleep.
206  */
hdaps_device_init(void)207 static int hdaps_device_init(void)
208 {
209 	int total, ret = -ENXIO;
210 
211 	mutex_lock(&hdaps_mtx);
212 
213 	outb(0x13, 0x1610);
214 	outb(0x01, 0x161f);
215 	if (__wait_latch(0x161f, 0x00))
216 		goto out;
217 
218 	/*
219 	 * Most ThinkPads return 0x01.
220 	 *
221 	 * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
222 	 * have "inverted" axises.
223 	 *
224 	 * The 0x02 value occurs when the chip has been previously initialized.
225 	 */
226 	if (__check_latch(0x1611, 0x03) &&
227 		     __check_latch(0x1611, 0x02) &&
228 		     __check_latch(0x1611, 0x01))
229 		goto out;
230 
231 	printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x)\n",
232 	       __get_latch(0x1611));
233 
234 	outb(0x17, 0x1610);
235 	outb(0x81, 0x1611);
236 	outb(0x01, 0x161f);
237 	if (__wait_latch(0x161f, 0x00))
238 		goto out;
239 	if (__wait_latch(0x1611, 0x00))
240 		goto out;
241 	if (__wait_latch(0x1612, 0x60))
242 		goto out;
243 	if (__wait_latch(0x1613, 0x00))
244 		goto out;
245 	outb(0x14, 0x1610);
246 	outb(0x01, 0x1611);
247 	outb(0x01, 0x161f);
248 	if (__wait_latch(0x161f, 0x00))
249 		goto out;
250 	outb(0x10, 0x1610);
251 	outb(0xc8, 0x1611);
252 	outb(0x00, 0x1612);
253 	outb(0x02, 0x1613);
254 	outb(0x01, 0x161f);
255 	if (__wait_latch(0x161f, 0x00))
256 		goto out;
257 	if (__device_refresh_sync())
258 		goto out;
259 	if (__wait_latch(0x1611, 0x00))
260 		goto out;
261 
262 	/* we have done our dance, now let's wait for the applause */
263 	for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
264 		int x, y;
265 
266 		/* a read of the device helps push it into action */
267 		__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
268 		if (!__wait_latch(0x1611, 0x02)) {
269 			ret = 0;
270 			break;
271 		}
272 
273 		msleep(INIT_WAIT_MSECS);
274 	}
275 
276 out:
277 	mutex_unlock(&hdaps_mtx);
278 	return ret;
279 }
280 
281 
282 /* Device model stuff */
283 
hdaps_probe(struct platform_device * dev)284 static int hdaps_probe(struct platform_device *dev)
285 {
286 	int ret;
287 
288 	ret = hdaps_device_init();
289 	if (ret)
290 		return ret;
291 
292 	pr_info("device successfully initialized\n");
293 	return 0;
294 }
295 
296 #ifdef CONFIG_PM_SLEEP
hdaps_resume(struct device * dev)297 static int hdaps_resume(struct device *dev)
298 {
299 	return hdaps_device_init();
300 }
301 #endif
302 
303 static SIMPLE_DEV_PM_OPS(hdaps_pm, NULL, hdaps_resume);
304 
305 static struct platform_driver hdaps_driver = {
306 	.probe = hdaps_probe,
307 	.driver	= {
308 		.name = "hdaps",
309 		.pm = &hdaps_pm,
310 	},
311 };
312 
313 /*
314  * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_mtx.
315  */
hdaps_calibrate(void)316 static void hdaps_calibrate(void)
317 {
318 	__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
319 }
320 
hdaps_mousedev_poll(struct input_dev * input_dev)321 static void hdaps_mousedev_poll(struct input_dev *input_dev)
322 {
323 	int x, y;
324 
325 	mutex_lock(&hdaps_mtx);
326 
327 	if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
328 		goto out;
329 
330 	input_report_abs(input_dev, ABS_X, x - rest_x);
331 	input_report_abs(input_dev, ABS_Y, y - rest_y);
332 	input_sync(input_dev);
333 
334 out:
335 	mutex_unlock(&hdaps_mtx);
336 }
337 
338 
339 /* Sysfs Files */
340 
hdaps_position_show(struct device * dev,struct device_attribute * attr,char * buf)341 static ssize_t hdaps_position_show(struct device *dev,
342 				   struct device_attribute *attr, char *buf)
343 {
344 	int ret, x, y;
345 
346 	ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
347 	if (ret)
348 		return ret;
349 
350 	return sprintf(buf, "(%d,%d)\n", x, y);
351 }
352 
hdaps_variance_show(struct device * dev,struct device_attribute * attr,char * buf)353 static ssize_t hdaps_variance_show(struct device *dev,
354 				   struct device_attribute *attr, char *buf)
355 {
356 	int ret, x, y;
357 
358 	ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
359 	if (ret)
360 		return ret;
361 
362 	return sprintf(buf, "(%d,%d)\n", x, y);
363 }
364 
hdaps_temp1_show(struct device * dev,struct device_attribute * attr,char * buf)365 static ssize_t hdaps_temp1_show(struct device *dev,
366 				struct device_attribute *attr, char *buf)
367 {
368 	u8 temp;
369 	int ret;
370 
371 	ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
372 	if (ret)
373 		return ret;
374 
375 	return sprintf(buf, "%u\n", temp);
376 }
377 
hdaps_temp2_show(struct device * dev,struct device_attribute * attr,char * buf)378 static ssize_t hdaps_temp2_show(struct device *dev,
379 				struct device_attribute *attr, char *buf)
380 {
381 	u8 temp;
382 	int ret;
383 
384 	ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
385 	if (ret)
386 		return ret;
387 
388 	return sprintf(buf, "%u\n", temp);
389 }
390 
hdaps_keyboard_activity_show(struct device * dev,struct device_attribute * attr,char * buf)391 static ssize_t hdaps_keyboard_activity_show(struct device *dev,
392 					    struct device_attribute *attr,
393 					    char *buf)
394 {
395 	return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
396 }
397 
hdaps_mouse_activity_show(struct device * dev,struct device_attribute * attr,char * buf)398 static ssize_t hdaps_mouse_activity_show(struct device *dev,
399 					 struct device_attribute *attr,
400 					 char *buf)
401 {
402 	return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
403 }
404 
hdaps_calibrate_show(struct device * dev,struct device_attribute * attr,char * buf)405 static ssize_t hdaps_calibrate_show(struct device *dev,
406 				    struct device_attribute *attr, char *buf)
407 {
408 	return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
409 }
410 
hdaps_calibrate_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)411 static ssize_t hdaps_calibrate_store(struct device *dev,
412 				     struct device_attribute *attr,
413 				     const char *buf, size_t count)
414 {
415 	mutex_lock(&hdaps_mtx);
416 	hdaps_calibrate();
417 	mutex_unlock(&hdaps_mtx);
418 
419 	return count;
420 }
421 
hdaps_invert_show(struct device * dev,struct device_attribute * attr,char * buf)422 static ssize_t hdaps_invert_show(struct device *dev,
423 				 struct device_attribute *attr, char *buf)
424 {
425 	return sprintf(buf, "%u\n", hdaps_invert);
426 }
427 
hdaps_invert_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)428 static ssize_t hdaps_invert_store(struct device *dev,
429 				  struct device_attribute *attr,
430 				  const char *buf, size_t count)
431 {
432 	int invert;
433 
434 	if (sscanf(buf, "%d", &invert) != 1 ||
435 	    invert < 0 || invert > HDAPS_BOTH_AXES)
436 		return -EINVAL;
437 
438 	hdaps_invert = invert;
439 	hdaps_calibrate();
440 
441 	return count;
442 }
443 
444 static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
445 static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
446 static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
447 static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
448 static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
449 static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
450 static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
451 static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
452 
453 static struct attribute *hdaps_attributes[] = {
454 	&dev_attr_position.attr,
455 	&dev_attr_variance.attr,
456 	&dev_attr_temp1.attr,
457 	&dev_attr_temp2.attr,
458 	&dev_attr_keyboard_activity.attr,
459 	&dev_attr_mouse_activity.attr,
460 	&dev_attr_calibrate.attr,
461 	&dev_attr_invert.attr,
462 	NULL,
463 };
464 
465 static const struct attribute_group hdaps_attribute_group = {
466 	.attrs = hdaps_attributes,
467 };
468 
469 
470 /* Module stuff */
471 
472 /* hdaps_dmi_match - found a match.  return one, short-circuiting the hunt. */
hdaps_dmi_match(const struct dmi_system_id * id)473 static int __init hdaps_dmi_match(const struct dmi_system_id *id)
474 {
475 	pr_info("%s detected\n", id->ident);
476 	return 1;
477 }
478 
479 /* hdaps_dmi_match_invert - found an inverted match. */
hdaps_dmi_match_invert(const struct dmi_system_id * id)480 static int __init hdaps_dmi_match_invert(const struct dmi_system_id *id)
481 {
482 	hdaps_invert = (unsigned long)id->driver_data;
483 	pr_info("inverting axis (%u) readings\n", hdaps_invert);
484 	return hdaps_dmi_match(id);
485 }
486 
487 #define HDAPS_DMI_MATCH_INVERT(vendor, model, axes) {	\
488 	.ident = vendor " " model,			\
489 	.callback = hdaps_dmi_match_invert,		\
490 	.driver_data = (void *)axes,			\
491 	.matches = {					\
492 		DMI_MATCH(DMI_BOARD_VENDOR, vendor),	\
493 		DMI_MATCH(DMI_PRODUCT_VERSION, model)	\
494 	}						\
495 }
496 
497 #define HDAPS_DMI_MATCH_NORMAL(vendor, model)		\
498 	HDAPS_DMI_MATCH_INVERT(vendor, model, 0)
499 
500 /* Note that HDAPS_DMI_MATCH_NORMAL("ThinkPad T42") would match
501    "ThinkPad T42p", so the order of the entries matters.
502    If your ThinkPad is not recognized, please update to latest
503    BIOS. This is especially the case for some R52 ThinkPads. */
504 static const struct dmi_system_id hdaps_whitelist[] __initconst = {
505 	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad R50p", HDAPS_BOTH_AXES),
506 	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R50"),
507 	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R51"),
508 	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad R52"),
509 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61i", HDAPS_BOTH_AXES),
510 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad R61", HDAPS_BOTH_AXES),
511 	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T41p", HDAPS_BOTH_AXES),
512 	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T41"),
513 	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad T42p", HDAPS_BOTH_AXES),
514 	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T42"),
515 	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad T43"),
516 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T400", HDAPS_BOTH_AXES),
517 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T60", HDAPS_BOTH_AXES),
518 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61p", HDAPS_BOTH_AXES),
519 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad T61", HDAPS_BOTH_AXES),
520 	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad X40"),
521 	HDAPS_DMI_MATCH_INVERT("IBM", "ThinkPad X41", HDAPS_Y_AXIS),
522 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X60", HDAPS_BOTH_AXES),
523 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61s", HDAPS_BOTH_AXES),
524 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad X61", HDAPS_BOTH_AXES),
525 	HDAPS_DMI_MATCH_NORMAL("IBM", "ThinkPad Z60m"),
526 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61m", HDAPS_BOTH_AXES),
527 	HDAPS_DMI_MATCH_INVERT("LENOVO", "ThinkPad Z61p", HDAPS_BOTH_AXES),
528 	{ .ident = NULL }
529 };
530 
hdaps_init(void)531 static int __init hdaps_init(void)
532 {
533 	int ret;
534 
535 	if (!dmi_check_system(hdaps_whitelist)) {
536 		pr_warn("supported laptop not found!\n");
537 		ret = -ENODEV;
538 		goto out;
539 	}
540 
541 	if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
542 		ret = -ENXIO;
543 		goto out;
544 	}
545 
546 	ret = platform_driver_register(&hdaps_driver);
547 	if (ret)
548 		goto out_region;
549 
550 	pdev = platform_device_register_simple("hdaps", PLATFORM_DEVID_NONE, NULL, 0);
551 	if (IS_ERR(pdev)) {
552 		ret = PTR_ERR(pdev);
553 		goto out_driver;
554 	}
555 
556 	ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
557 	if (ret)
558 		goto out_device;
559 
560 	hdaps_idev = input_allocate_device();
561 	if (!hdaps_idev) {
562 		ret = -ENOMEM;
563 		goto out_group;
564 	}
565 
566 	/* initial calibrate for the input device */
567 	hdaps_calibrate();
568 
569 	/* initialize the input class */
570 	hdaps_idev->name = "hdaps";
571 	hdaps_idev->phys = "isa1600/input0";
572 	hdaps_idev->id.bustype = BUS_ISA;
573 	hdaps_idev->dev.parent = &pdev->dev;
574 	input_set_abs_params(hdaps_idev, ABS_X,
575 			-256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
576 	input_set_abs_params(hdaps_idev, ABS_Y,
577 			-256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
578 
579 	ret = input_setup_polling(hdaps_idev, hdaps_mousedev_poll);
580 	if (ret)
581 		goto out_idev;
582 
583 	input_set_poll_interval(hdaps_idev, HDAPS_POLL_INTERVAL);
584 
585 	ret = input_register_device(hdaps_idev);
586 	if (ret)
587 		goto out_idev;
588 
589 	pr_info("driver successfully loaded\n");
590 	return 0;
591 
592 out_idev:
593 	input_free_device(hdaps_idev);
594 out_group:
595 	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
596 out_device:
597 	platform_device_unregister(pdev);
598 out_driver:
599 	platform_driver_unregister(&hdaps_driver);
600 out_region:
601 	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
602 out:
603 	pr_warn("driver init failed (ret=%d)!\n", ret);
604 	return ret;
605 }
606 
hdaps_exit(void)607 static void __exit hdaps_exit(void)
608 {
609 	input_unregister_device(hdaps_idev);
610 	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
611 	platform_device_unregister(pdev);
612 	platform_driver_unregister(&hdaps_driver);
613 	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
614 
615 	pr_info("driver unloaded\n");
616 }
617 
618 module_init(hdaps_init);
619 module_exit(hdaps_exit);
620 
621 module_param_named(invert, hdaps_invert, int, 0);
622 MODULE_PARM_DESC(invert, "invert data along each axis. 1 invert x-axis, "
623 		 "2 invert y-axis, 3 invert both axes.");
624 
625 MODULE_AUTHOR("Robert Love");
626 MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
627 MODULE_LICENSE("GPL v2");
628