Linux v2.6.18-rc5

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

/*
 * drivers/hwmon/hdaps.c - driver for IBM's Hard Drive Active Protection System
 *
 * Copyright (C) 2005 Robert Love <rml@novell.com>
 * Copyright (C) 2005 Jesper Juhl <jesper.juhl@gmail.com>
 *
 * 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/platform_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 Celsius */
#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 */
#define HDAPS_INPUT_FLAT        4

static struct timer_list hdaps_timer;
static struct platform_device *pdev;
static struct input_dev *hdaps_idev;
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 platform_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 platform_device *dev)
{
        return hdaps_device_init();
}

static struct platform_driver hdaps_driver = {
        .probe = hdaps_probe,
        .resume = hdaps_resume,
        .driver = {
                .name = "hdaps",
                .owner = THIS_MODULE,
        },
};

/*
 * 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)   \
        }                                               \
}

#define HDAPS_DMI_MATCH_LENOVO(model)   {               \
        .ident = "Lenovo " model,                       \
        .callback = hdaps_dmi_match_invert,             \
        .matches = {                                    \
                DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"),  \
                DMI_MATCH(DMI_PRODUCT_VERSION, model)   \
        }                                               \
}

static int __init hdaps_init(void)
{
        int ret;

        /* Note that HDAPS_DMI_MATCH_NORMAL("ThinkPad T42") would match
          "ThinkPad T42p", so the order of the entries matters */
        struct dmi_system_id hdaps_whitelist[] = {
                HDAPS_DMI_MATCH_NORMAL("ThinkPad H"),
                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_NORMAL("ThinkPad H"),    /* R52 (1846AQG) */
                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_LENOVO("ThinkPad T60p"),
                HDAPS_DMI_MATCH_NORMAL("ThinkPad X40"),
                HDAPS_DMI_MATCH_NORMAL("ThinkPad X41"),
                HDAPS_DMI_MATCH_LENOVO("ThinkPad X60"),
                HDAPS_DMI_MATCH_NORMAL("ThinkPad Z60m"),
                { .ident = NULL }
        };

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

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

        ret = platform_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;

        hdaps_idev = input_allocate_device();
        if (!hdaps_idev) {
                ret = -ENOMEM;
                goto out_group;
        }

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

        /* initialize the input class */
        hdaps_idev->name = "hdaps";
        hdaps_idev->cdev.dev = &pdev->dev;
        hdaps_idev->evbit[0] = BIT(EV_ABS);
        input_set_abs_params(hdaps_idev, ABS_X,
                        -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);
        input_set_abs_params(hdaps_idev, ABS_Y,
                        -256, 256, HDAPS_INPUT_FUZZ, HDAPS_INPUT_FLAT);

        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_group:
        sysfs_remove_group(&pdev->dev.kobj, &hdaps_attribute_group);
out_device:
        platform_device_unregister(pdev);
out_driver:
        platform_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);
        platform_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");