[linux.git] / drivers / hwmon / hdaps.c

/*
 * drivers/hwmon/hdaps.c - driver for IBM's Hard Drive Active Protection System
 *
 * Copyright (C) 2005 Robert Love <[email protected]>
 * Copyright (C) 2005 Jesper Juhl <[email protected]>
 *
 * The HardDisk Active Protection System (hdaps) is present in IBM ThinkPads
 * starting with the R40, T41, and X40.  It provides a basic two-axis
 * accelerometer and other data, such as the device's temperature.
 *
 * This driver is based on the document by Mark A. Smith available at
 * http://www.almaden.ibm.com/cs/people/marksmith/tpaps.html and a lot of trial
 * and error.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License v2 as published by the
 * Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#include <linux/delay.h>
#include <linux/device.h>
#include <linux/input.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/timer.h>
#include <linux/dmi.h>
#include <asm/io.h>

#define HDAPS_LOW_PORT		0x1600	/* first port used by hdaps */
#define HDAPS_NR_PORTS		0x30	/* number of ports: 0x1600 - 0x162f */

#define HDAPS_PORT_STATE	0x1611	/* device state */
#define HDAPS_PORT_YPOS		0x1612	/* y-axis position */
#define	HDAPS_PORT_XPOS		0x1614	/* x-axis position */
#define HDAPS_PORT_TEMP1	0x1616	/* device temperature, in celcius */
#define HDAPS_PORT_YVAR		0x1617	/* y-axis variance (what is this?) */
#define HDAPS_PORT_XVAR		0x1619	/* x-axis variance (what is this?) */
#define HDAPS_PORT_TEMP2	0x161b	/* device temperature (again?) */
#define HDAPS_PORT_UNKNOWN	0x161c	/* what is this? */
#define HDAPS_PORT_KMACT	0x161d	/* keyboard or mouse activity */

#define STATE_FRESH		0x50	/* accelerometer data is fresh */

#define KEYBD_MASK		0x20	/* set if keyboard activity */
#define MOUSE_MASK		0x40	/* set if mouse activity */
#define KEYBD_ISSET(n)		(!! (n & KEYBD_MASK))	/* keyboard used? */
#define MOUSE_ISSET(n)		(!! (n & MOUSE_MASK))	/* mouse used? */

#define INIT_TIMEOUT_MSECS	4000	/* wait up to 4s for device init ... */
#define INIT_WAIT_MSECS		200	/* ... in 200ms increments */

#define HDAPS_POLL_PERIOD	(HZ/20)	/* poll for input every 1/20s */
#define HDAPS_INPUT_FUZZ	4	/* input event threshold */

static struct timer_list hdaps_timer;
static struct platform_device *pdev;
static unsigned int hdaps_invert;
static u8 km_activity;
static int rest_x;
static int rest_y;

static DECLARE_MUTEX(hdaps_sem);

/*
 * __get_latch - Get the value from a given port.  Callers must hold hdaps_sem.
 */
static inline u8 __get_latch(u16 port)
{
	return inb(port) & 0xff;
}

/*
 * __check_latch - Check a port latch for a given value.  Returns zero if the
 * port contains the given value.  Callers must hold hdaps_sem.
 */
static inline int __check_latch(u16 port, u8 val)
{
	if (__get_latch(port) == val)
		return 0;
	return -EINVAL;
}

/*
 * __wait_latch - Wait up to 100us for a port latch to get a certain value,
 * returning zero if the value is obtained.  Callers must hold hdaps_sem.
 */
static int __wait_latch(u16 port, u8 val)
{
	unsigned int i;

	for (i = 0; i < 20; i++) {
		if (!__check_latch(port, val))
			return 0;
		udelay(5);
	}

	return -EIO;
}

/*
 * __device_refresh - request a refresh from the accelerometer.  Does not wait
 * for refresh to complete.  Callers must hold hdaps_sem.
 */
static void __device_refresh(void)
{
	udelay(200);
	if (inb(0x1604) != STATE_FRESH) {
		outb(0x11, 0x1610);
		outb(0x01, 0x161f);
	}
}

/*
 * __device_refresh_sync - request a synchronous refresh from the
 * accelerometer.  We wait for the refresh to complete.  Returns zero if
 * successful and nonzero on error.  Callers must hold hdaps_sem.
 */
static int __device_refresh_sync(void)
{
	__device_refresh();
	return __wait_latch(0x1604, STATE_FRESH);
}

/*
 * __device_complete - indicate to the accelerometer that we are done reading
 * data, and then initiate an async refresh.  Callers must hold hdaps_sem.
 */
static inline void __device_complete(void)
{
	inb(0x161f);
	inb(0x1604);
	__device_refresh();
}

/*
 * hdaps_readb_one - reads a byte from a single I/O port, placing the value in
 * the given pointer.  Returns zero on success or a negative error on failure.
 * Can sleep.
 */
static int hdaps_readb_one(unsigned int port, u8 *val)
{
	int ret;

	down(&hdaps_sem);

	/* do a sync refresh -- we need to be sure that we read fresh data */
	ret = __device_refresh_sync();
	if (ret)
		goto out;

	*val = inb(port);
	__device_complete();

out:
	up(&hdaps_sem);
	return ret;
}

/* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
			     int *x, int *y)
{
	/* do a sync refresh -- we need to be sure that we read fresh data */
	if (__device_refresh_sync())
		return -EIO;

	*y = inw(port2);
	*x = inw(port1);
	km_activity = inb(HDAPS_PORT_KMACT);
	__device_complete();

	/* if hdaps_invert is set, negate the two values */
	if (hdaps_invert) {
		*x = -*x;
		*y = -*y;
	}

	return 0;
}

/*
 * hdaps_read_pair - reads the values from a pair of ports, placing the values
 * in the given pointers.  Returns zero on success.  Can sleep.
 */
static int hdaps_read_pair(unsigned int port1, unsigned int port2,
			   int *val1, int *val2)
{
	int ret;

	down(&hdaps_sem);
	ret = __hdaps_read_pair(port1, port2, val1, val2);
	up(&hdaps_sem);

	return ret;
}

/*
 * hdaps_device_init - initialize the accelerometer.  Returns zero on success
 * and negative error code on failure.  Can sleep.
 */
static int hdaps_device_init(void)
{
	int total, ret = -ENXIO;

	down(&hdaps_sem);

	outb(0x13, 0x1610);
	outb(0x01, 0x161f);
	if (__wait_latch(0x161f, 0x00))
		goto out;

	/*
	 * Most ThinkPads return 0x01.
	 *
	 * Others--namely the R50p, T41p, and T42p--return 0x03.  These laptops
	 * have "inverted" axises.
	 *
	 * The 0x02 value occurs when the chip has been previously initialized.
	 */
	if (__check_latch(0x1611, 0x03) &&
		     __check_latch(0x1611, 0x02) &&
		     __check_latch(0x1611, 0x01))
		goto out;

	printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
	       __get_latch(0x1611));

	outb(0x17, 0x1610);
	outb(0x81, 0x1611);
	outb(0x01, 0x161f);
	if (__wait_latch(0x161f, 0x00))
		goto out;
	if (__wait_latch(0x1611, 0x00))
		goto out;
	if (__wait_latch(0x1612, 0x60))
		goto out;
	if (__wait_latch(0x1613, 0x00))
		goto out;
	outb(0x14, 0x1610);
	outb(0x01, 0x1611);
	outb(0x01, 0x161f);
	if (__wait_latch(0x161f, 0x00))
		goto out;
	outb(0x10, 0x1610);
	outb(0xc8, 0x1611);
	outb(0x00, 0x1612);
	outb(0x02, 0x1613);
	outb(0x01, 0x161f);
	if (__wait_latch(0x161f, 0x00))
		goto out;
	if (__device_refresh_sync())
		goto out;
	if (__wait_latch(0x1611, 0x00))
		goto out;

	/* we have done our dance, now let's wait for the applause */
	for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
		int x, y;

		/* a read of the device helps push it into action */
		__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
		if (!__wait_latch(0x1611, 0x02)) {
			ret = 0;
			break;
		}

		msleep(INIT_WAIT_MSECS);
	}

out:
	up(&hdaps_sem);
	return ret;
}


/* Device model stuff */

static int hdaps_probe(struct device *dev)
{
	int ret;

	ret = hdaps_device_init();
	if (ret)
		return ret;

	printk(KERN_INFO "hdaps: device successfully initialized.\n");
	return 0;
}

static int hdaps_resume(struct device *dev)
{
	return hdaps_device_init();
}

static struct device_driver hdaps_driver = {
	.name = "hdaps",
	.bus = &platform_bus_type,
	.owner = THIS_MODULE,
	.probe = hdaps_probe,
	.resume = hdaps_resume
};

/* Input class stuff */

static struct input_dev hdaps_idev = {
	.name = "hdaps",
	.evbit = { BIT(EV_ABS) },
	.absbit = { BIT(ABS_X) | BIT(ABS_Y) },
	.absmin  = { [ABS_X] = -256, [ABS_Y] = -256 },
	.absmax  = { [ABS_X] = 256, [ABS_Y] = 256 },
	.absfuzz = { [ABS_X] = HDAPS_INPUT_FUZZ, [ABS_Y] = HDAPS_INPUT_FUZZ },
	.absflat = { [ABS_X] = HDAPS_INPUT_FUZZ, [ABS_Y] = HDAPS_INPUT_FUZZ },
};

/*
 * hdaps_calibrate - Set our "resting" values.  Callers must hold hdaps_sem.
 */
static void hdaps_calibrate(void)
{
	__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
}

static void hdaps_mousedev_poll(unsigned long unused)
{
	int x, y;

	/* Cannot sleep.  Try nonblockingly.  If we fail, try again later. */
	if (down_trylock(&hdaps_sem)) {
		mod_timer(&hdaps_timer,jiffies + HDAPS_POLL_PERIOD);
		return;
	}

	if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
		goto out;

	input_report_abs(&hdaps_idev, ABS_X, x - rest_x);
	input_report_abs(&hdaps_idev, ABS_Y, y - rest_y);
	input_sync(&hdaps_idev);

	mod_timer(&hdaps_timer, jiffies + HDAPS_POLL_PERIOD);

out:
	up(&hdaps_sem);
}


/* Sysfs Files */

static ssize_t hdaps_position_show(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	int ret, x, y;

	ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
	if (ret)
		return ret;

	return sprintf(buf, "(%d,%d)\n", x, y);
}

static ssize_t hdaps_variance_show(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	int ret, x, y;

	ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
	if (ret)
		return ret;

	return sprintf(buf, "(%d,%d)\n", x, y);
}

static ssize_t hdaps_temp1_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	u8 temp;
	int ret;

	ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%u\n", temp);
}

static ssize_t hdaps_temp2_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	u8 temp;
	int ret;

	ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%u\n", temp);
}

static ssize_t hdaps_keyboard_activity_show(struct device *dev,
					    struct device_attribute *attr,
					    char *buf)
{
	return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
}

static ssize_t hdaps_mouse_activity_show(struct device *dev,
					 struct device_attribute *attr,
					 char *buf)
{
	return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
}

static ssize_t hdaps_calibrate_show(struct device *dev,
				    struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
}

static ssize_t hdaps_calibrate_store(struct device *dev,
				     struct device_attribute *attr,
				     const char *buf, size_t count)
{
	down(&hdaps_sem);
	hdaps_calibrate();
	up(&hdaps_sem);

	return count;
}

static ssize_t hdaps_invert_show(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "%u\n", hdaps_invert);
}

static ssize_t hdaps_invert_store(struct device *dev,
				  struct device_attribute *attr,
				  const char *buf, size_t count)
{
	int invert;

	if (sscanf(buf, "%d", &invert) != 1 || (invert != 1 && invert != 0))
		return -EINVAL;

	hdaps_invert = invert;
	hdaps_calibrate();

	return count;
}

static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);

static struct attribute *hdaps_attributes[] = {
	&dev_attr_position.attr,
	&dev_attr_variance.attr,
	&dev_attr_temp1.attr,
	&dev_attr_temp2.attr,
	&dev_attr_keyboard_activity.attr,
	&dev_attr_mouse_activity.attr,
	&dev_attr_calibrate.attr,
	&dev_attr_invert.attr,
	NULL,
};

static struct attribute_group hdaps_attribute_group = {
	.attrs = hdaps_attributes,
};


/* Module stuff */

/* hdaps_dmi_match - found a match.  return one, short-circuiting the hunt. */
static int hdaps_dmi_match(struct dmi_system_id *id)
{
	printk(KERN_INFO "hdaps: %s detected.\n", id->ident);
	return 1;
}

/* hdaps_dmi_match_invert - found an inverted match. */
static int hdaps_dmi_match_invert(struct dmi_system_id *id)
{
	hdaps_invert = 1;
	printk(KERN_INFO "hdaps: inverting axis readings.\n");
	return hdaps_dmi_match(id);
}

#define HDAPS_DMI_MATCH_NORMAL(model)	{		\
	.ident = "IBM " model,				\
	.callback = hdaps_dmi_match,			\
	.matches = {					\
		DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),	\
		DMI_MATCH(DMI_PRODUCT_VERSION, model)	\
	}						\
}

#define HDAPS_DMI_MATCH_INVERT(model)	{		\
	.ident = "IBM " model,				\
	.callback = hdaps_dmi_match_invert,		\
	.matches = {					\
		DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),	\
		DMI_MATCH(DMI_PRODUCT_VERSION, model)	\
	}						\
}

static int __init hdaps_init(void)
{
	int ret;

	/* Note that DMI_MATCH(...,"ThinkPad T42") will match "ThinkPad T42p" */
	struct dmi_system_id hdaps_whitelist[] = {
		HDAPS_DMI_MATCH_INVERT("ThinkPad R50p"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad R50"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad R51"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad R52"),
		HDAPS_DMI_MATCH_INVERT("ThinkPad T41p"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad T41"),
		HDAPS_DMI_MATCH_INVERT("ThinkPad T42p"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad T42"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad T43"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad X40"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad X41 Tablet"),
		HDAPS_DMI_MATCH_NORMAL("ThinkPad X41"),
		{ .ident = NULL }
	};

	if (!dmi_check_system(hdaps_whitelist)) {
		printk(KERN_WARNING "hdaps: supported laptop not found!\n");
		ret = -ENXIO;
		goto out;
	}

	if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
		ret = -ENXIO;
		goto out;
	}

	ret = driver_register(&hdaps_driver);
	if (ret)
		goto out_region;

	pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
	if (IS_ERR(pdev)) {
		ret = PTR_ERR(pdev);
		goto out_driver;
	}

	ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
	if (ret)
		goto out_device;

	/* initial calibrate for the input device */
	hdaps_calibrate();

	/* initialize the input class */
	hdaps_idev.dev = &pdev->dev;
	input_register_device(&hdaps_idev);

	/* start up our timer for the input device */
	init_timer(&hdaps_timer);
	hdaps_timer.function = hdaps_mousedev_poll;
	hdaps_timer.expires = jiffies + HDAPS_POLL_PERIOD;
	add_timer(&hdaps_timer);

	printk(KERN_INFO "hdaps: driver successfully loaded.\n");
	return 0;

out_device:
	platform_device_unregister(pdev);
out_driver:
	driver_unregister(&hdaps_driver);
out_region:
	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
out:
	printk(KERN_WARNING "hdaps: driver init failed (ret=%d)!\n", ret);
	return ret;
}

static void __exit hdaps_exit(void)
{
	del_timer_sync(&hdaps_timer);
	input_unregister_device(&hdaps_idev);
	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
	platform_device_unregister(pdev);
	driver_unregister(&hdaps_driver);
	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);

	printk(KERN_INFO "hdaps: driver unloaded.\n");
}

module_init(hdaps_init);
module_exit(hdaps_exit);

module_param_named(invert, hdaps_invert, bool, 0);
MODULE_PARM_DESC(invert, "invert data along each axis");

MODULE_AUTHOR("Robert Love");
MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
860e1d6b RL	1	/*
	2	* drivers/hwmon/hdaps.c - driver for IBM's Hard Drive Active Protection System
	3	*
	4	* Copyright (C) 2005 Robert Love <[email protected]>
	5	* Copyright (C) 2005 Jesper Juhl <[email protected]>
	6	*
4c87b74c RL	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.
860e1d6b	10	*
393ad299	11	* This driver is based on the document by Mark A. Smith available at
860e1d6b RL	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/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 */
393ad299	39	#define HDAPS_NR_PORTS 0x30 /* number of ports: 0x1600 - 0x162f */
860e1d6b RL	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
393ad299	51	#define STATE_FRESH 0x50 /* accelerometer data is fresh */
860e1d6b RL	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
393ad299 RL	61	#define HDAPS_POLL_PERIOD (HZ/20) /* poll for input every 1/20s */
	62	#define HDAPS_INPUT_FUZZ 4 /* input event threshold */
	63
860e1d6b	64	static struct timer_list hdaps_timer;
393ad299	65	static struct platform_device *pdev;
860e1d6b RL	66	static unsigned int hdaps_invert;
	67	static u8 km_activity;
	68	static int rest_x;
	69	static int rest_y;
	70
	71	static DECLARE_MUTEX(hdaps_sem);
	72
	73	/*
	74	* __get_latch - Get the value from a given port. Callers must hold hdaps_sem.
	75	*/
	76	static inline u8 __get_latch(u16 port)
	77	{
393ad299	78	return inb(port) & 0xff;
860e1d6b RL	79	}
	80
	81	/*
393ad299 RL	82	* __check_latch - Check a port latch for a given value. Returns zero if the
393ad299 RL	83	* port contains the given value. Callers must hold hdaps_sem.
860e1d6b	84	*/
393ad299	85	static inline int __check_latch(u16 port, u8 val)
860e1d6b RL	86	{
	87	if (__get_latch(port) == val)
	88	return 0;
	89	return -EINVAL;
	90	}
	91
	92	/*
	93	* __wait_latch - Wait up to 100us for a port latch to get a certain value,
	94	* returning zero if the value is obtained. Callers must hold hdaps_sem.
	95	*/
393ad299	96	static int __wait_latch(u16 port, u8 val)
860e1d6b RL	97	{
	98	unsigned int i;
	99
	100	for (i = 0; i < 20; i++) {
	101	if (!__check_latch(port, val))
	102	return 0;
	103	udelay(5);
	104	}
	105
393ad299	106	return -EIO;
860e1d6b RL	107	}
	108
	109	/*
393ad299 RL	110	* __device_refresh - request a refresh from the accelerometer. Does not wait
393ad299 RL	111	* for refresh to complete. Callers must hold hdaps_sem.
860e1d6b	112	*/
393ad299	113	static void __device_refresh(void)
860e1d6b	114	{
393ad299 RL	115	udelay(200);
	116	if (inb(0x1604) != STATE_FRESH) {
	117	outb(0x11, 0x1610);
	118	outb(0x01, 0x161f);
	119	}
	120	}
860e1d6b	121
393ad299 RL	122	/*
	123	* __device_refresh_sync - request a synchronous refresh from the
	124	* accelerometer. We wait for the refresh to complete. Returns zero if
	125	* successful and nonzero on error. Callers must hold hdaps_sem.
	126	*/
	127	static int __device_refresh_sync(void)
	128	{
	129	__device_refresh();
860e1d6b RL	130	return __wait_latch(0x1604, STATE_FRESH);
	131	}
	132
	133	/*
393ad299	134	* __device_complete - indicate to the accelerometer that we are done reading
860e1d6b RL	135	* data, and then initiate an async refresh. Callers must hold hdaps_sem.
	136	*/
	137	static inline void __device_complete(void)
	138	{
	139	inb(0x161f);
	140	inb(0x1604);
393ad299	141	__device_refresh();
860e1d6b RL	142	}
	143
	144	/*
	145	* hdaps_readb_one - reads a byte from a single I/O port, placing the value in
	146	* the given pointer. Returns zero on success or a negative error on failure.
	147	* Can sleep.
	148	*/
	149	static int hdaps_readb_one(unsigned int port, u8 *val)
	150	{
	151	int ret;
	152
	153	down(&hdaps_sem);
860e1d6b	154
393ad299 RL	155	/* do a sync refresh -- we need to be sure that we read fresh data */
	156	ret = __device_refresh_sync();
	157	if (ret)
	158	goto out;
	159
	160	*val = inb(port);
	161	__device_complete();
	162
	163	out:
	164	up(&hdaps_sem);
860e1d6b RL	165	return ret;
	166	}
	167
393ad299	168	/* __hdaps_read_pair - internal lockless helper for hdaps_read_pair(). */
860e1d6b RL	169	static int __hdaps_read_pair(unsigned int port1, unsigned int port2,
	170	int x, int y)
	171	{
	172	/* do a sync refresh -- we need to be sure that we read fresh data */
393ad299	173	if (__device_refresh_sync())
860e1d6b RL	174	return -EIO;
	175
	176	*y = inw(port2);
	177	*x = inw(port1);
	178	km_activity = inb(HDAPS_PORT_KMACT);
	179	__device_complete();
	180
	181	/* if hdaps_invert is set, negate the two values */
	182	if (hdaps_invert) {
	183	x = -x;
	184	y = -y;
	185	}
	186
	187	return 0;
	188	}
	189
	190	/*
	191	* hdaps_read_pair - reads the values from a pair of ports, placing the values
	192	* in the given pointers. Returns zero on success. Can sleep.
	193	*/
	194	static int hdaps_read_pair(unsigned int port1, unsigned int port2,
	195	int val1, int val2)
	196	{
	197	int ret;
	198
	199	down(&hdaps_sem);
	200	ret = __hdaps_read_pair(port1, port2, val1, val2);
	201	up(&hdaps_sem);
	202
	203	return ret;
	204	}
	205
393ad299 RL	206	/*
	207	* hdaps_device_init - initialize the accelerometer. Returns zero on success
	208	* and negative error code on failure. Can sleep.
	209	*/
860e1d6b RL	210	static int hdaps_device_init(void)
860e1d6b RL	211	{
393ad299	212	int total, ret = -ENXIO;
860e1d6b RL	213
	214	down(&hdaps_sem);
	215
	216	outb(0x13, 0x1610);
	217	outb(0x01, 0x161f);
	218	if (__wait_latch(0x161f, 0x00))
	219	goto out;
	220
	221	/*
393ad299 RL	222	* Most ThinkPads return 0x01.
	223	*
	224	* Others--namely the R50p, T41p, and T42p--return 0x03. These laptops
	225	* have "inverted" axises.
860e1d6b RL	226	*
	227	* The 0x02 value occurs when the chip has been previously initialized.
	228	*/
	229	if (__check_latch(0x1611, 0x03) &&
	230	__check_latch(0x1611, 0x02) &&
	231	__check_latch(0x1611, 0x01))
	232	goto out;
	233
	234	printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
	235	__get_latch(0x1611));
	236
	237	outb(0x17, 0x1610);
	238	outb(0x81, 0x1611);
	239	outb(0x01, 0x161f);
	240	if (__wait_latch(0x161f, 0x00))
	241	goto out;
	242	if (__wait_latch(0x1611, 0x00))
	243	goto out;
	244	if (__wait_latch(0x1612, 0x60))
	245	goto out;
	246	if (__wait_latch(0x1613, 0x00))
	247	goto out;
	248	outb(0x14, 0x1610);
	249	outb(0x01, 0x1611);
	250	outb(0x01, 0x161f);
	251	if (__wait_latch(0x161f, 0x00))
	252	goto out;
	253	outb(0x10, 0x1610);
	254	outb(0xc8, 0x1611);
	255	outb(0x00, 0x1612);
	256	outb(0x02, 0x1613);
	257	outb(0x01, 0x161f);
	258	if (__wait_latch(0x161f, 0x00))
	259	goto out;
393ad299	260	if (__device_refresh_sync())
860e1d6b RL	261	goto out;
	262	if (__wait_latch(0x1611, 0x00))
	263	goto out;
	264
	265	/* we have done our dance, now let's wait for the applause */
393ad299 RL	266	for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
393ad299 RL	267	int x, y;
860e1d6b RL	268
860e1d6b RL	269	/* a read of the device helps push it into action */
393ad299	270	__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
860e1d6b RL	271	if (!__wait_latch(0x1611, 0x02)) {
	272	ret = 0;
	273	break;
	274	}
	275
	276	msleep(INIT_WAIT_MSECS);
860e1d6b RL	277	}
	278
	279	out:
	280	up(&hdaps_sem);
	281	return ret;
	282	}
	283
	284
860e1d6b RL	285	/* Device model stuff */
	286
	287	static int hdaps_probe(struct device *dev)
	288	{
	289	int ret;
	290
	291	ret = hdaps_device_init();
	292	if (ret)
	293	return ret;
	294
	295	printk(KERN_INFO "hdaps: device successfully initialized.\n");
	296	return 0;
	297	}
	298
9480e307	299	static int hdaps_resume(struct device *dev)
860e1d6b	300	{
9480e307	301	return hdaps_device_init();
860e1d6b RL	302	}
	303
	304	static struct device_driver hdaps_driver = {
	305	.name = "hdaps",
	306	.bus = &platform_bus_type,
	307	.owner = THIS_MODULE,
	308	.probe = hdaps_probe,
	309	.resume = hdaps_resume
	310	};
	311
393ad299 RL	312	/* Input class stuff */
	313
	314	static struct input_dev hdaps_idev = {
	315	.name = "hdaps",
	316	.evbit = { BIT(EV_ABS) },
	317	.absbit = { BIT(ABS_X) \| BIT(ABS_Y) },
	318	.absmin = { [ABS_X] = -256, [ABS_Y] = -256 },
	319	.absmax = { [ABS_X] = 256, [ABS_Y] = 256 },
	320	.absfuzz = { [ABS_X] = HDAPS_INPUT_FUZZ, [ABS_Y] = HDAPS_INPUT_FUZZ },
	321	.absflat = { [ABS_X] = HDAPS_INPUT_FUZZ, [ABS_Y] = HDAPS_INPUT_FUZZ },
	322	};
	323
	324	/*
	325	* hdaps_calibrate - Set our "resting" values. Callers must hold hdaps_sem.
	326	*/
	327	static void hdaps_calibrate(void)
	328	{
	329	__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &rest_x, &rest_y);
	330	}
	331
	332	static void hdaps_mousedev_poll(unsigned long unused)
	333	{
	334	int x, y;
	335
	336	/* Cannot sleep. Try nonblockingly. If we fail, try again later. */
	337	if (down_trylock(&hdaps_sem)) {
	338	mod_timer(&hdaps_timer,jiffies + HDAPS_POLL_PERIOD);
	339	return;
	340	}
	341
	342	if (__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y))
	343	goto out;
	344
	345	input_report_abs(&hdaps_idev, ABS_X, x - rest_x);
	346	input_report_abs(&hdaps_idev, ABS_Y, y - rest_y);
	347	input_sync(&hdaps_idev);
	348
	349	mod_timer(&hdaps_timer, jiffies + HDAPS_POLL_PERIOD);
	350
	351	out:
	352	up(&hdaps_sem);
	353	}
	354
860e1d6b RL	355
	356	/* Sysfs Files */
	357
	358	static ssize_t hdaps_position_show(struct device *dev,
	359	struct device_attribute attr, char buf)
	360	{
	361	int ret, x, y;
	362
	363	ret = hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
	364	if (ret)
	365	return ret;
	366
	367	return sprintf(buf, "(%d,%d)\n", x, y);
	368	}
	369
	370	static ssize_t hdaps_variance_show(struct device *dev,
	371	struct device_attribute attr, char buf)
	372	{
	373	int ret, x, y;
	374
	375	ret = hdaps_read_pair(HDAPS_PORT_XVAR, HDAPS_PORT_YVAR, &x, &y);
	376	if (ret)
	377	return ret;
	378
	379	return sprintf(buf, "(%d,%d)\n", x, y);
	380	}
	381
	382	static ssize_t hdaps_temp1_show(struct device *dev,
	383	struct device_attribute attr, char buf)
	384	{
	385	u8 temp;
	386	int ret;
	387
	388	ret = hdaps_readb_one(HDAPS_PORT_TEMP1, &temp);
	389	if (ret < 0)
	390	return ret;
	391
	392	return sprintf(buf, "%u\n", temp);
	393	}
	394
	395	static ssize_t hdaps_temp2_show(struct device *dev,
	396	struct device_attribute attr, char buf)
	397	{
	398	u8 temp;
	399	int ret;
	400
	401	ret = hdaps_readb_one(HDAPS_PORT_TEMP2, &temp);
	402	if (ret < 0)
	403	return ret;
	404
	405	return sprintf(buf, "%u\n", temp);
	406	}
	407
	408	static ssize_t hdaps_keyboard_activity_show(struct device *dev,
	409	struct device_attribute *attr,
	410	char *buf)
	411	{
	412	return sprintf(buf, "%u\n", KEYBD_ISSET(km_activity));
	413	}
	414
	415	static ssize_t hdaps_mouse_activity_show(struct device *dev,
	416	struct device_attribute *attr,
	417	char *buf)
	418	{
419	return sprintf(buf, "%u\n", MOUSE_ISSET(km_activity));
420	}
421
422	static ssize_t hdaps_calibrate_show(struct device *dev,
423	struct device_attribute attr, char buf)
424	{
425	return sprintf(buf, "(%d,%d)\n", rest_x, rest_y);
426	}
427
428	static ssize_t hdaps_calibrate_store(struct device *dev,
429	struct device_attribute *attr,
430	const char *buf, size_t count)
431	{
432	down(&hdaps_sem);
433	hdaps_calibrate();
434	up(&hdaps_sem);
435
436	return count;
437	}
438
439	static ssize_t hdaps_invert_show(struct device *dev,
440	struct device_attribute attr, char buf)
441	{
442	return sprintf(buf, "%u\n", hdaps_invert);
443	}
444
445	static ssize_t hdaps_invert_store(struct device *dev,
446	struct device_attribute *attr,
447	const char *buf, size_t count)
448	{
449	int invert;
450
451	if (sscanf(buf, "%d", &invert) != 1 \|\| (invert != 1 && invert != 0))
452	return -EINVAL;
453
454	hdaps_invert = invert;
455	hdaps_calibrate();
456
457	return count;
458	}
459
860e1d6b RL	460	static DEVICE_ATTR(position, 0444, hdaps_position_show, NULL);
	461	static DEVICE_ATTR(variance, 0444, hdaps_variance_show, NULL);
	462	static DEVICE_ATTR(temp1, 0444, hdaps_temp1_show, NULL);
	463	static DEVICE_ATTR(temp2, 0444, hdaps_temp2_show, NULL);
	464	static DEVICE_ATTR(keyboard_activity, 0444, hdaps_keyboard_activity_show, NULL);
	465	static DEVICE_ATTR(mouse_activity, 0444, hdaps_mouse_activity_show, NULL);
	466	static DEVICE_ATTR(calibrate, 0644, hdaps_calibrate_show,hdaps_calibrate_store);
	467	static DEVICE_ATTR(invert, 0644, hdaps_invert_show, hdaps_invert_store);
860e1d6b RL	468
	469	static struct attribute *hdaps_attributes[] = {
	470	&dev_attr_position.attr,
	471	&dev_attr_variance.attr,
	472	&dev_attr_temp1.attr,
	473	&dev_attr_temp2.attr,
	474	&dev_attr_keyboard_activity.attr,
	475	&dev_attr_mouse_activity.attr,
	476	&dev_attr_calibrate.attr,
860e1d6b RL	477	&dev_attr_invert.attr,
	478	NULL,
	479	};
	480
	481	static struct attribute_group hdaps_attribute_group = {
	482	.attrs = hdaps_attributes,
	483	};
	484
	485
	486	/* Module stuff */
	487
4c87b74c	488	/* hdaps_dmi_match - found a match. return one, short-circuiting the hunt. */
860e1d6b RL	489	static int hdaps_dmi_match(struct dmi_system_id *id)
	490	{
	491	printk(KERN_INFO "hdaps: %s detected.\n", id->ident);
4c87b74c	492	return 1;
860e1d6b RL	493	}
860e1d6b RL	494
4c87b74c	495	/* hdaps_dmi_match_invert - found an inverted match. */
860e1d6b RL	496	static int hdaps_dmi_match_invert(struct dmi_system_id *id)
	497	{
	498	hdaps_invert = 1;
	499	printk(KERN_INFO "hdaps: inverting axis readings.\n");
4c87b74c	500	return hdaps_dmi_match(id);
860e1d6b RL	501	}
	502
	503	#define HDAPS_DMI_MATCH_NORMAL(model) { \
	504	.ident = "IBM " model, \
	505	.callback = hdaps_dmi_match, \
	506	.matches = { \
	507	DMI_MATCH(DMI_BOARD_VENDOR, "IBM"), \
	508	DMI_MATCH(DMI_PRODUCT_VERSION, model) \
	509	} \
	510	}
	511
	512	#define HDAPS_DMI_MATCH_INVERT(model) { \
	513	.ident = "IBM " model, \
	514	.callback = hdaps_dmi_match_invert, \
	515	.matches = { \
	516	DMI_MATCH(DMI_BOARD_VENDOR, "IBM"), \
	517	DMI_MATCH(DMI_PRODUCT_VERSION, model) \
	518	} \
	519	}
	520
	521	static int __init hdaps_init(void)
	522	{
	523	int ret;
	524
	525	/* Note that DMI_MATCH(...,"ThinkPad T42") will match "ThinkPad T42p" */
	526	struct dmi_system_id hdaps_whitelist[] = {
	527	HDAPS_DMI_MATCH_INVERT("ThinkPad R50p"),
	528	HDAPS_DMI_MATCH_NORMAL("ThinkPad R50"),
	529	HDAPS_DMI_MATCH_NORMAL("ThinkPad R51"),
4c87b74c	530	HDAPS_DMI_MATCH_NORMAL("ThinkPad R52"),
860e1d6b RL	531	HDAPS_DMI_MATCH_INVERT("ThinkPad T41p"),
	532	HDAPS_DMI_MATCH_NORMAL("ThinkPad T41"),
	533	HDAPS_DMI_MATCH_INVERT("ThinkPad T42p"),
	534	HDAPS_DMI_MATCH_NORMAL("ThinkPad T42"),
	535	HDAPS_DMI_MATCH_NORMAL("ThinkPad T43"),
	536	HDAPS_DMI_MATCH_NORMAL("ThinkPad X40"),
393ad299	537	HDAPS_DMI_MATCH_NORMAL("ThinkPad X41 Tablet"),
4c87b74c	538	HDAPS_DMI_MATCH_NORMAL("ThinkPad X41"),
860e1d6b RL	539	{ .ident = NULL }
	540	};
	541
	542	if (!dmi_check_system(hdaps_whitelist)) {
	543	printk(KERN_WARNING "hdaps: supported laptop not found!\n");
	544	ret = -ENXIO;
	545	goto out;
	546	}
	547
	548	if (!request_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS, "hdaps")) {
	549	ret = -ENXIO;
	550	goto out;
	551	}
	552
	553	ret = driver_register(&hdaps_driver);
	554	if (ret)
	555	goto out_region;
	556
	557	pdev = platform_device_register_simple("hdaps", -1, NULL, 0);
	558	if (IS_ERR(pdev)) {
	559	ret = PTR_ERR(pdev);
	560	goto out_driver;
	561	}
	562
	563	ret = sysfs_create_group(&pdev->dev.kobj, &hdaps_attribute_group);
	564	if (ret)
	565	goto out_device;
	566
393ad299 RL	567	/* initial calibrate for the input device */
	568	hdaps_calibrate();
	569
	570	/* initialize the input class */
	571	hdaps_idev.dev = &pdev->dev;
	572	input_register_device(&hdaps_idev);
	573
	574	/* start up our timer for the input device */
	575	init_timer(&hdaps_timer);
	576	hdaps_timer.function = hdaps_mousedev_poll;
	577	hdaps_timer.expires = jiffies + HDAPS_POLL_PERIOD;
	578	add_timer(&hdaps_timer);
860e1d6b RL	579
	580	printk(KERN_INFO "hdaps: driver successfully loaded.\n");
	581	return 0;
	582
	583	out_device:
	584	platform_device_unregister(pdev);
	585	out_driver:
	586	driver_unregister(&hdaps_driver);
	587	out_region:
	588	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
	589	out:
	590	printk(KERN_WARNING "hdaps: driver init failed (ret=%d)!\n", ret);
	591	return ret;
	592	}
	593
	594	static void __exit hdaps_exit(void)
	595	{
393ad299 RL	596	del_timer_sync(&hdaps_timer);
393ad299 RL	597	input_unregister_device(&hdaps_idev);
860e1d6b RL	598	sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
	599	platform_device_unregister(pdev);
	600	driver_unregister(&hdaps_driver);
	601	release_region(HDAPS_LOW_PORT, HDAPS_NR_PORTS);
	602
	603	printk(KERN_INFO "hdaps: driver unloaded.\n");
	604	}
	605
	606	module_init(hdaps_init);
	607	module_exit(hdaps_exit);
	608
860e1d6b RL	609	module_param_named(invert, hdaps_invert, bool, 0);
	610	MODULE_PARM_DESC(invert, "invert data along each axis");
	611
	612	MODULE_AUTHOR("Robert Love");
	613	MODULE_DESCRIPTION("IBM Hard Drive Active Protection System (HDAPS) driver");
	614	MODULE_LICENSE("GPL v2");