Pull bugzilla-3774 into release branch

[deliverable/linux.git] / drivers / hwmon / applesmc.c

/*
 * drivers/hwmon/applesmc.c - driver for Apple's SMC (accelerometer, temperature
 * sensors, fan control, keyboard backlight control) used in Intel-based Apple
 * computers.
 *
 * Copyright (C) 2007 Nicolas Boichat <nicolas@boichat.ch>
 *
 * Based on hdaps.c driver:
 * Copyright (C) 2005 Robert Love <rml@novell.com>
 * Copyright (C) 2005 Jesper Juhl <jesper.juhl@gmail.com>
 *
 * Fan control based on smcFanControl:
 * Copyright (C) 2006 Hendrik Holtmann <holtmann@mac.com>
 *
 * 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 <linux/mutex.h>
#include <linux/hwmon-sysfs.h>
#include <asm/io.h>
#include <linux/leds.h>
#include <linux/hwmon.h>
#include <linux/workqueue.h>

/* data port used by Apple SMC */
#define APPLESMC_DATA_PORT      0x300
/* command/status port used by Apple SMC */
#define APPLESMC_CMD_PORT       0x304

#define APPLESMC_NR_PORTS       32 /* 0x300-0x31f */

#define APPLESMC_MAX_DATA_LENGTH 32

#define APPLESMC_STATUS_MASK    0x0f
#define APPLESMC_READ_CMD       0x10
#define APPLESMC_WRITE_CMD      0x11
#define APPLESMC_GET_KEY_BY_INDEX_CMD   0x12
#define APPLESMC_GET_KEY_TYPE_CMD       0x13

#define KEY_COUNT_KEY           "#KEY" /* r-o ui32 */

#define LIGHT_SENSOR_LEFT_KEY   "ALV0" /* r-o {alv (6 bytes) */
#define LIGHT_SENSOR_RIGHT_KEY  "ALV1" /* r-o {alv (6 bytes) */
#define BACKLIGHT_KEY           "LKSB" /* w-o {lkb (2 bytes) */

#define CLAMSHELL_KEY           "MSLD" /* r-o ui8 (unused) */

#define MOTION_SENSOR_X_KEY     "MO_X" /* r-o sp78 (2 bytes) */
#define MOTION_SENSOR_Y_KEY     "MO_Y" /* r-o sp78 (2 bytes) */
#define MOTION_SENSOR_Z_KEY     "MO_Z" /* r-o sp78 (2 bytes) */
#define MOTION_SENSOR_KEY       "MOCN" /* r/w ui16 */

#define FANS_COUNT              "FNum" /* r-o ui8 */
#define FANS_MANUAL             "FS! " /* r-w ui16 */
#define FAN_ACTUAL_SPEED        "F0Ac" /* r-o fpe2 (2 bytes) */
#define FAN_MIN_SPEED           "F0Mn" /* r-o fpe2 (2 bytes) */
#define FAN_MAX_SPEED           "F0Mx" /* r-o fpe2 (2 bytes) */
#define FAN_SAFE_SPEED          "F0Sf" /* r-o fpe2 (2 bytes) */
#define FAN_TARGET_SPEED        "F0Tg" /* r-w fpe2 (2 bytes) */
#define FAN_POSITION            "F0ID" /* r-o char[16] */

/*
 * Temperature sensors keys (sp78 - 2 bytes).
 */
static const char* temperature_sensors_sets[][13] = {
/* Set 0: Macbook Pro */
        { "TA0P", "TB0T", "TC0D", "TC0P", "TG0H", "TG0P", "TG0T", "Th0H",
          "Th1H", "Tm0P", "Ts0P", "Ts1P", NULL },
/* Set 1: Macbook set */
        { "TB0T", "TC0D", "TC0P", "TM0P", "TN0P", "TN1P", "Th0H", "Th0S",
          "Th1H", "Ts0P", NULL },
/* Set 2: Macmini set */
        { "TC0D", "TC0P", NULL }
};

/* List of keys used to read/write fan speeds */
static const char* fan_speed_keys[] = {
        FAN_ACTUAL_SPEED,
        FAN_MIN_SPEED,
        FAN_MAX_SPEED,
        FAN_SAFE_SPEED,
        FAN_TARGET_SPEED
};

#define INIT_TIMEOUT_MSECS      5000    /* wait up to 5s for device init ... */
#define INIT_WAIT_MSECS         50      /* ... in 50ms increments */

#define APPLESMC_POLL_PERIOD    (HZ/20) /* poll for input every 1/20s */
#define APPLESMC_INPUT_FUZZ     4       /* input event threshold */
#define APPLESMC_INPUT_FLAT     4

#define SENSOR_X 0
#define SENSOR_Y 1
#define SENSOR_Z 2

/* Structure to be passed to DMI_MATCH function */
struct dmi_match_data {
/* Indicates whether this computer has an accelerometer. */
        int accelerometer;
/* Indicates whether this computer has light sensors and keyboard backlight. */
        int light;
/* Indicates which temperature sensors set to use. */
        int temperature_set;
};

static const int debug;
static struct platform_device *pdev;
static s16 rest_x;
static s16 rest_y;
static struct timer_list applesmc_timer;
static struct input_dev *applesmc_idev;
static struct class_device *hwmon_class_dev;

/* Indicates whether this computer has an accelerometer. */
static unsigned int applesmc_accelerometer;

/* Indicates whether this computer has light sensors and keyboard backlight. */
static unsigned int applesmc_light;

/* Indicates which temperature sensors set to use. */
static unsigned int applesmc_temperature_set;

static struct mutex applesmc_lock;

/*
 * Last index written to key_at_index sysfs file, and value to use for all other
 * key_at_index_* sysfs files.
 */
static unsigned int key_at_index;

static struct workqueue_struct *applesmc_led_wq;

/*
 * __wait_status - Wait up to 2ms for the status port to get a certain value
 * (masked with 0x0f), returning zero if the value is obtained.  Callers must
 * hold applesmc_lock.
 */
static int __wait_status(u8 val)
{
        unsigned int i;

        val = val & APPLESMC_STATUS_MASK;

        for (i = 0; i < 200; i++) {
                if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == val) {
                        if (debug)
                                printk(KERN_DEBUG
                                                "Waited %d us for status %x\n",
                                                i*10, val);
                        return 0;
                }
                udelay(10);
        }

        printk(KERN_WARNING "applesmc: wait status failed: %x != %x\n",
                                                val, inb(APPLESMC_CMD_PORT));

        return -EIO;
}

/*
 * applesmc_read_key - reads len bytes from a given key, and put them in buffer.
 * Returns zero on success or a negative error on failure. Callers must
 * hold applesmc_lock.
 */
static int applesmc_read_key(const char* key, u8* buffer, u8 len)
{
        int i;

        if (len > APPLESMC_MAX_DATA_LENGTH) {
                printk(KERN_ERR "applesmc_read_key: cannot read more than "
                                        "%d bytes\n", APPLESMC_MAX_DATA_LENGTH);
                return -EINVAL;
        }

        outb(APPLESMC_READ_CMD, APPLESMC_CMD_PORT);
        if (__wait_status(0x0c))
                return -EIO;

        for (i = 0; i < 4; i++) {
                outb(key[i], APPLESMC_DATA_PORT);
                if (__wait_status(0x04))
                        return -EIO;
        }
        if (debug)
                printk(KERN_DEBUG "<%s", key);

        outb(len, APPLESMC_DATA_PORT);
        if (debug)
                printk(KERN_DEBUG ">%x", len);

        for (i = 0; i < len; i++) {
                if (__wait_status(0x05))
                        return -EIO;
                buffer[i] = inb(APPLESMC_DATA_PORT);
                if (debug)
                        printk(KERN_DEBUG "<%x", buffer[i]);
        }
        if (debug)
                printk(KERN_DEBUG "\n");

        return 0;
}

/*
 * applesmc_write_key - writes len bytes from buffer to a given key.
 * Returns zero on success or a negative error on failure. Callers must
 * hold applesmc_lock.
 */
static int applesmc_write_key(const char* key, u8* buffer, u8 len)
{
        int i;

        if (len > APPLESMC_MAX_DATA_LENGTH) {
                printk(KERN_ERR "applesmc_write_key: cannot write more than "
                                        "%d bytes\n", APPLESMC_MAX_DATA_LENGTH);
                return -EINVAL;
        }

        outb(APPLESMC_WRITE_CMD, APPLESMC_CMD_PORT);
        if (__wait_status(0x0c))
                return -EIO;

        for (i = 0; i < 4; i++) {
                outb(key[i], APPLESMC_DATA_PORT);
                if (__wait_status(0x04))
                        return -EIO;
        }

        outb(len, APPLESMC_DATA_PORT);

        for (i = 0; i < len; i++) {
                if (__wait_status(0x04))
                        return -EIO;
                outb(buffer[i], APPLESMC_DATA_PORT);
        }

        return 0;
}

/*
 * applesmc_get_key_at_index - get key at index, and put the result in key
 * (char[6]). Returns zero on success or a negative error on failure. Callers
 * must hold applesmc_lock.
 */
static int applesmc_get_key_at_index(int index, char* key)
{
        int i;
        u8 readkey[4];
        readkey[0] = index >> 24;
        readkey[1] = index >> 16;
        readkey[2] = index >> 8;
        readkey[3] = index;

        outb(APPLESMC_GET_KEY_BY_INDEX_CMD, APPLESMC_CMD_PORT);
        if (__wait_status(0x0c))
                return -EIO;

        for (i = 0; i < 4; i++) {
                outb(readkey[i], APPLESMC_DATA_PORT);
                if (__wait_status(0x04))
                        return -EIO;
        }

        outb(4, APPLESMC_DATA_PORT);

        for (i = 0; i < 4; i++) {
                if (__wait_status(0x05))
                        return -EIO;
                key[i] = inb(APPLESMC_DATA_PORT);
        }
        key[4] = 0;

        return 0;
}

/*
 * applesmc_get_key_type - get key type, and put the result in type (char[6]).
 * Returns zero on success or a negative error on failure. Callers must
 * hold applesmc_lock.
 */
static int applesmc_get_key_type(char* key, char* type)
{
        int i;

        outb(APPLESMC_GET_KEY_TYPE_CMD, APPLESMC_CMD_PORT);
        if (__wait_status(0x0c))
                return -EIO;

        for (i = 0; i < 4; i++) {
                outb(key[i], APPLESMC_DATA_PORT);
                if (__wait_status(0x04))
                        return -EIO;
        }

        outb(5, APPLESMC_DATA_PORT);

        for (i = 0; i < 6; i++) {
                if (__wait_status(0x05))
                        return -EIO;
                type[i] = inb(APPLESMC_DATA_PORT);
        }
        type[5] = 0;

        return 0;
}

/*
 * applesmc_read_motion_sensor - Read motion sensor (X, Y or Z). Callers must
 * hold applesmc_lock.
 */
static int applesmc_read_motion_sensor(int index, s16* value)
{
        u8 buffer[2];
        int ret;

        switch (index) {
        case SENSOR_X:
                ret = applesmc_read_key(MOTION_SENSOR_X_KEY, buffer, 2);
                break;
        case SENSOR_Y:
                ret = applesmc_read_key(MOTION_SENSOR_Y_KEY, buffer, 2);
                break;
        case SENSOR_Z:
                ret = applesmc_read_key(MOTION_SENSOR_Z_KEY, buffer, 2);
                break;
        default:
                ret = -EINVAL;
        }

        *value = ((s16)buffer[0] << 8) | buffer[1];

        return ret;
}

/*
 * applesmc_device_init - initialize the accelerometer.  Returns zero on success
 * and negative error code on failure.  Can sleep.
 */
static int applesmc_device_init(void)
{
        int total, ret = -ENXIO;
        u8 buffer[2];

        if (!applesmc_accelerometer)
                return 0;

        mutex_lock(&applesmc_lock);

        for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
                if (debug)
                        printk(KERN_DEBUG "applesmc try %d\n", total);
                if (!applesmc_read_key(MOTION_SENSOR_KEY, buffer, 2) &&
                                (buffer[0] != 0x00 || buffer[1] != 0x00)) {
                        if (total == INIT_TIMEOUT_MSECS) {
                                printk(KERN_DEBUG "applesmc: device has"
                                                " already been initialized"
                                                " (0x%02x, 0x%02x).\n",
                                                buffer[0], buffer[1]);
                        } else {
                                printk(KERN_DEBUG "applesmc: device"
                                                " successfully initialized"
                                                " (0x%02x, 0x%02x).\n",
                                                buffer[0], buffer[1]);
                        }
                        ret = 0;
                        goto out;
                }
                buffer[0] = 0xe0;
                buffer[1] = 0x00;
                applesmc_write_key(MOTION_SENSOR_KEY, buffer, 2);
                msleep(INIT_WAIT_MSECS);
        }

        printk(KERN_WARNING "applesmc: failed to init the device\n");

out:
        mutex_unlock(&applesmc_lock);
        return ret;
}

/*
 * applesmc_get_fan_count - get the number of fans. Callers must NOT hold
 * applesmc_lock.
 */
static int applesmc_get_fan_count(void)
{
        int ret;
        u8 buffer[1];

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_key(FANS_COUNT, buffer, 1);

        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return buffer[0];
}

/* Device model stuff */
static int applesmc_probe(struct platform_device *dev)
{
        int ret;

        ret = applesmc_device_init();
        if (ret)
                return ret;

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

static int applesmc_resume(struct platform_device *dev)
{
        return applesmc_device_init();
}

static struct platform_driver applesmc_driver = {
        .probe = applesmc_probe,
        .resume = applesmc_resume,
        .driver = {
                .name = "applesmc",
                .owner = THIS_MODULE,
        },
};

/*
 * applesmc_calibrate - Set our "resting" values.  Callers must
 * hold applesmc_lock.
 */
static void applesmc_calibrate(void)
{
        applesmc_read_motion_sensor(SENSOR_X, &rest_x);
        applesmc_read_motion_sensor(SENSOR_Y, &rest_y);
        rest_x = -rest_x;
}

static int applesmc_idev_open(struct input_dev *dev)
{
        add_timer(&applesmc_timer);

        return 0;
}

static void applesmc_idev_close(struct input_dev *dev)
{
        del_timer_sync(&applesmc_timer);
}

static void applesmc_idev_poll(unsigned long unused)
{
        s16 x, y;

        /* Cannot sleep.  Try nonblockingly.  If we fail, try again later. */
        if (!mutex_trylock(&applesmc_lock)) {
                mod_timer(&applesmc_timer, jiffies + APPLESMC_POLL_PERIOD);
                return;
        }

        if (applesmc_read_motion_sensor(SENSOR_X, &x))
                goto out;
        if (applesmc_read_motion_sensor(SENSOR_Y, &y))
                goto out;

        x = -x;
        input_report_abs(applesmc_idev, ABS_X, x - rest_x);
        input_report_abs(applesmc_idev, ABS_Y, y - rest_y);
        input_sync(applesmc_idev);

out:
        mod_timer(&applesmc_timer, jiffies + APPLESMC_POLL_PERIOD);

        mutex_unlock(&applesmc_lock);
}

/* Sysfs Files */

static ssize_t applesmc_name_show(struct device *dev,
                                   struct device_attribute *attr, char *buf)
{
        return snprintf(buf, PAGE_SIZE, "applesmc\n");
}

static ssize_t applesmc_position_show(struct device *dev,
                                   struct device_attribute *attr, char *buf)
{
        int ret;
        s16 x, y, z;

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_motion_sensor(SENSOR_X, &x);
        if (ret)
                goto out;
        ret = applesmc_read_motion_sensor(SENSOR_Y, &y);
        if (ret)
                goto out;
        ret = applesmc_read_motion_sensor(SENSOR_Z, &z);
        if (ret)
                goto out;

out:
        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return snprintf(buf, PAGE_SIZE, "(%d,%d,%d)\n", x, y, z);
}

static ssize_t applesmc_light_show(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        int ret;
        u8 left = 0, right = 0;
        u8 buffer[6];

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, buffer, 6);
        left = buffer[2];
        if (ret)
                goto out;
        ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, 6);
        right = buffer[2];

out:
        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", left, right);
}

/* Displays degree Celsius * 1000 */
static ssize_t applesmc_show_temperature(struct device *dev,
                        struct device_attribute *devattr, char *sysfsbuf)
{
        int ret;
        u8 buffer[2];
        unsigned int temp;
        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
        const char* key =
                temperature_sensors_sets[applesmc_temperature_set][attr->index];

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_key(key, buffer, 2);
        temp = buffer[0]*1000;
        temp += (buffer[1] >> 6) * 250;

        mutex_unlock(&applesmc_lock);

        if (ret)
                return ret;
        else
                return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", temp);
}

static ssize_t applesmc_show_fan_speed(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        int ret;
        unsigned int speed = 0;
        char newkey[5];
        u8 buffer[2];
        struct sensor_device_attribute_2 *sensor_attr =
                                                to_sensor_dev_attr_2(attr);

        newkey[0] = fan_speed_keys[sensor_attr->nr][0];
        newkey[1] = '0' + sensor_attr->index;
        newkey[2] = fan_speed_keys[sensor_attr->nr][2];
        newkey[3] = fan_speed_keys[sensor_attr->nr][3];
        newkey[4] = 0;

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_key(newkey, buffer, 2);
        speed = ((buffer[0] << 8 | buffer[1]) >> 2);

        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
}

static ssize_t applesmc_store_fan_speed(struct device *dev,
                                        struct device_attribute *attr,
                                        const char *sysfsbuf, size_t count)
{
        int ret;
        u32 speed;
        char newkey[5];
        u8 buffer[2];
        struct sensor_device_attribute_2 *sensor_attr =
                                                to_sensor_dev_attr_2(attr);

        speed = simple_strtoul(sysfsbuf, NULL, 10);

        if (speed > 0x4000) /* Bigger than a 14-bit value */
                return -EINVAL;

        newkey[0] = fan_speed_keys[sensor_attr->nr][0];
        newkey[1] = '0' + sensor_attr->index;
        newkey[2] = fan_speed_keys[sensor_attr->nr][2];
        newkey[3] = fan_speed_keys[sensor_attr->nr][3];
        newkey[4] = 0;

        mutex_lock(&applesmc_lock);

        buffer[0] = (speed >> 6) & 0xff;
        buffer[1] = (speed << 2) & 0xff;
        ret = applesmc_write_key(newkey, buffer, 2);

        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return count;
}

static ssize_t applesmc_show_fan_manual(struct device *dev,
                        struct device_attribute *devattr, char *sysfsbuf)
{
        int ret;
        u16 manual = 0;
        u8 buffer[2];
        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
        manual = ((buffer[0] << 8 | buffer[1]) >> attr->index) & 0x01;

        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
}

static ssize_t applesmc_store_fan_manual(struct device *dev,
                                         struct device_attribute *devattr,
                                         const char *sysfsbuf, size_t count)
{
        int ret;
        u8 buffer[2];
        u32 input;
        u16 val;
        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

        input = simple_strtoul(sysfsbuf, NULL, 10);

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
        val = (buffer[0] << 8 | buffer[1]);
        if (ret)
                goto out;

        if (input)
                val = val | (0x01 << attr->index);
        else
                val = val & ~(0x01 << attr->index);

        buffer[0] = (val >> 8) & 0xFF;
        buffer[1] = val & 0xFF;

        ret = applesmc_write_key(FANS_MANUAL, buffer, 2);

out:
        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return count;
}

static ssize_t applesmc_show_fan_position(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        int ret;
        char newkey[5];
        u8 buffer[17];
        struct sensor_device_attribute_2 *sensor_attr =
                                                to_sensor_dev_attr_2(attr);

        newkey[0] = FAN_POSITION[0];
        newkey[1] = '0' + sensor_attr->index;
        newkey[2] = FAN_POSITION[2];
        newkey[3] = FAN_POSITION[3];
        newkey[4] = 0;

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_key(newkey, buffer, 16);
        buffer[16] = 0;

        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", buffer+4);
}

static ssize_t applesmc_calibrate_show(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", rest_x, rest_y);
}

static ssize_t applesmc_calibrate_store(struct device *dev,
        struct device_attribute *attr, const char *sysfsbuf, size_t count)
{
        mutex_lock(&applesmc_lock);
        applesmc_calibrate();
        mutex_unlock(&applesmc_lock);

        return count;
}

/* Store the next backlight value to be written by the work */
static unsigned int backlight_value;

static void applesmc_backlight_set(struct work_struct *work)
{
        u8 buffer[2];

        mutex_lock(&applesmc_lock);
        buffer[0] = backlight_value;
        buffer[1] = 0x00;
        applesmc_write_key(BACKLIGHT_KEY, buffer, 2);
        mutex_unlock(&applesmc_lock);
}
static DECLARE_WORK(backlight_work, &applesmc_backlight_set);

static void applesmc_brightness_set(struct led_classdev *led_cdev,
                                                enum led_brightness value)
{
        int ret;

        backlight_value = value;
        ret = queue_work(applesmc_led_wq, &backlight_work);

        if (debug && (!ret))
                printk(KERN_DEBUG "applesmc: work was already on the queue.\n");
}

static ssize_t applesmc_key_count_show(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        int ret;
        u8 buffer[4];
        u32 count;

        mutex_lock(&applesmc_lock);

        ret = applesmc_read_key(KEY_COUNT_KEY, buffer, 4);
        count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
                                                ((u32)buffer[2]<<8) + buffer[3];

        mutex_unlock(&applesmc_lock);
        if (ret)
                return ret;
        else
                return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
}

static ssize_t applesmc_key_at_index_read_show(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        char key[5];
        char info[6];
        int ret;

        mutex_lock(&applesmc_lock);

        ret = applesmc_get_key_at_index(key_at_index, key);

        if (ret || !key[0]) {
                mutex_unlock(&applesmc_lock);

                return -EINVAL;
        }

        ret = applesmc_get_key_type(key, info);

        if (ret) {
                mutex_unlock(&applesmc_lock);

                return ret;
        }

        /*
         * info[0] maximum value (APPLESMC_MAX_DATA_LENGTH) is much lower than
         * PAGE_SIZE, so we don't need any checks before writing to sysfsbuf.
         */
        ret = applesmc_read_key(key, sysfsbuf, info[0]);

        mutex_unlock(&applesmc_lock);

        if (!ret) {
                return info[0];
        }
        else {
                return ret;
        }
}

static ssize_t applesmc_key_at_index_data_length_show(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        char key[5];
        char info[6];
        int ret;

        mutex_lock(&applesmc_lock);

        ret = applesmc_get_key_at_index(key_at_index, key);

        if (ret || !key[0]) {
                mutex_unlock(&applesmc_lock);

                return -EINVAL;
        }

        ret = applesmc_get_key_type(key, info);

        mutex_unlock(&applesmc_lock);

        if (!ret)
                return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", info[0]);
        else
                return ret;
}

static ssize_t applesmc_key_at_index_type_show(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        char key[5];
        char info[6];
        int ret;

        mutex_lock(&applesmc_lock);

        ret = applesmc_get_key_at_index(key_at_index, key);

        if (ret || !key[0]) {
                mutex_unlock(&applesmc_lock);

                return -EINVAL;
        }

        ret = applesmc_get_key_type(key, info);

        mutex_unlock(&applesmc_lock);

        if (!ret)
                return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", info+1);
        else
                return ret;
}

static ssize_t applesmc_key_at_index_name_show(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        char key[5];
        int ret;

        mutex_lock(&applesmc_lock);

        ret = applesmc_get_key_at_index(key_at_index, key);

        mutex_unlock(&applesmc_lock);

        if (!ret && key[0])
                return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", key);
        else
                return -EINVAL;
}

static ssize_t applesmc_key_at_index_show(struct device *dev,
                                struct device_attribute *attr, char *sysfsbuf)
{
        return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", key_at_index);
}

static ssize_t applesmc_key_at_index_store(struct device *dev,
        struct device_attribute *attr, const char *sysfsbuf, size_t count)
{
        mutex_lock(&applesmc_lock);

        key_at_index = simple_strtoul(sysfsbuf, NULL, 10);

        mutex_unlock(&applesmc_lock);

        return count;
}

static struct led_classdev applesmc_backlight = {
        .name                   = "smc:kbd_backlight",
        .default_trigger        = "nand-disk",
        .brightness_set         = applesmc_brightness_set,
};

static DEVICE_ATTR(name, 0444, applesmc_name_show, NULL);

static DEVICE_ATTR(position, 0444, applesmc_position_show, NULL);
static DEVICE_ATTR(calibrate, 0644,
                        applesmc_calibrate_show, applesmc_calibrate_store);

static struct attribute *accelerometer_attributes[] = {
        &dev_attr_position.attr,
        &dev_attr_calibrate.attr,
        NULL
};

static const struct attribute_group accelerometer_attributes_group =
        { .attrs = accelerometer_attributes };

static DEVICE_ATTR(light, 0444, applesmc_light_show, NULL);

static DEVICE_ATTR(key_count, 0444, applesmc_key_count_show, NULL);
static DEVICE_ATTR(key_at_index, 0644,
                applesmc_key_at_index_show, applesmc_key_at_index_store);
static DEVICE_ATTR(key_at_index_name, 0444,
                                        applesmc_key_at_index_name_show, NULL);
static DEVICE_ATTR(key_at_index_type, 0444,
                                        applesmc_key_at_index_type_show, NULL);
static DEVICE_ATTR(key_at_index_data_length, 0444,
                                applesmc_key_at_index_data_length_show, NULL);
static DEVICE_ATTR(key_at_index_data, 0444,
                                applesmc_key_at_index_read_show, NULL);

static struct attribute *key_enumeration_attributes[] = {
        &dev_attr_key_count.attr,
        &dev_attr_key_at_index.attr,
        &dev_attr_key_at_index_name.attr,
        &dev_attr_key_at_index_type.attr,
        &dev_attr_key_at_index_data_length.attr,
        &dev_attr_key_at_index_data.attr,
        NULL
};

static const struct attribute_group key_enumeration_group =
        { .attrs = key_enumeration_attributes };

/*
 * Macro defining SENSOR_DEVICE_ATTR for a fan sysfs entries.
 *  - show actual speed
 *  - show/store minimum speed
 *  - show maximum speed
 *  - show safe speed
 *  - show/store target speed
 *  - show/store manual mode
 */
#define sysfs_fan_speeds_offset(offset) \
static SENSOR_DEVICE_ATTR_2(fan##offset##_input, S_IRUGO, \
                        applesmc_show_fan_speed, NULL, 0, offset-1); \
\
static SENSOR_DEVICE_ATTR_2(fan##offset##_min, S_IRUGO | S_IWUSR, \
        applesmc_show_fan_speed, applesmc_store_fan_speed, 1, offset-1); \
\
static SENSOR_DEVICE_ATTR_2(fan##offset##_max, S_IRUGO, \
                        applesmc_show_fan_speed, NULL, 2, offset-1); \
\
static SENSOR_DEVICE_ATTR_2(fan##offset##_safe, S_IRUGO, \
                        applesmc_show_fan_speed, NULL, 3, offset-1); \
\
static SENSOR_DEVICE_ATTR_2(fan##offset##_output, S_IRUGO | S_IWUSR, \
        applesmc_show_fan_speed, applesmc_store_fan_speed, 4, offset-1); \
\
static SENSOR_DEVICE_ATTR(fan##offset##_manual, S_IRUGO | S_IWUSR, \
        applesmc_show_fan_manual, applesmc_store_fan_manual, offset-1); \
\
static SENSOR_DEVICE_ATTR(fan##offset##_label, S_IRUGO, \
        applesmc_show_fan_position, NULL, offset-1); \
\
static struct attribute *fan##offset##_attributes[] = { \
        &sensor_dev_attr_fan##offset##_input.dev_attr.attr, \
        &sensor_dev_attr_fan##offset##_min.dev_attr.attr, \
        &sensor_dev_attr_fan##offset##_max.dev_attr.attr, \
        &sensor_dev_attr_fan##offset##_safe.dev_attr.attr, \
        &sensor_dev_attr_fan##offset##_output.dev_attr.attr, \
        &sensor_dev_attr_fan##offset##_manual.dev_attr.attr, \
        &sensor_dev_attr_fan##offset##_label.dev_attr.attr, \
        NULL \
};

/*
 * Create the needed functions for each fan using the macro defined above
 * (2 fans are supported)
 */
sysfs_fan_speeds_offset(1);
sysfs_fan_speeds_offset(2);

static const struct attribute_group fan_attribute_groups[] = {
        { .attrs = fan1_attributes },
        { .attrs = fan2_attributes }
};

/*
 * Temperature sensors sysfs entries.
 */
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 0);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 1);
static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 2);
static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 3);
static SENSOR_DEVICE_ATTR(temp5_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 4);
static SENSOR_DEVICE_ATTR(temp6_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 5);
static SENSOR_DEVICE_ATTR(temp7_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 6);
static SENSOR_DEVICE_ATTR(temp8_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 7);
static SENSOR_DEVICE_ATTR(temp9_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 8);
static SENSOR_DEVICE_ATTR(temp10_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 9);
static SENSOR_DEVICE_ATTR(temp11_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 10);
static SENSOR_DEVICE_ATTR(temp12_input, S_IRUGO,
                                        applesmc_show_temperature, NULL, 11);

static struct attribute *temperature_attributes[] = {
        &sensor_dev_attr_temp1_input.dev_attr.attr,
        &sensor_dev_attr_temp2_input.dev_attr.attr,
        &sensor_dev_attr_temp3_input.dev_attr.attr,
        &sensor_dev_attr_temp4_input.dev_attr.attr,
        &sensor_dev_attr_temp5_input.dev_attr.attr,
        &sensor_dev_attr_temp6_input.dev_attr.attr,
        &sensor_dev_attr_temp7_input.dev_attr.attr,
        &sensor_dev_attr_temp8_input.dev_attr.attr,
        &sensor_dev_attr_temp9_input.dev_attr.attr,
        &sensor_dev_attr_temp10_input.dev_attr.attr,
        &sensor_dev_attr_temp11_input.dev_attr.attr,
        &sensor_dev_attr_temp12_input.dev_attr.attr,
        NULL
};

static const struct attribute_group temperature_attributes_group =
        { .attrs = temperature_attributes };

/* Module stuff */

/*
 * applesmc_dmi_match - found a match.  return one, short-circuiting the hunt.
 */
static int applesmc_dmi_match(struct dmi_system_id *id)
{
        int i = 0;
        struct dmi_match_data* dmi_data = id->driver_data;
        printk(KERN_INFO "applesmc: %s detected:\n", id->ident);
        applesmc_accelerometer = dmi_data->accelerometer;
        printk(KERN_INFO "applesmc:  - Model %s accelerometer\n",
                                applesmc_accelerometer ? "with" : "without");
        applesmc_light = dmi_data->light;
        printk(KERN_INFO "applesmc:  - Model %s light sensors and backlight\n",
                                        applesmc_light ? "with" : "without");

        applesmc_temperature_set =  dmi_data->temperature_set;
        while (temperature_sensors_sets[applesmc_temperature_set][i] != NULL)
                i++;
        printk(KERN_INFO "applesmc:  - Model with %d temperature sensors\n", i);
        return 1;
}

/* Create accelerometer ressources */
static int applesmc_create_accelerometer(void)
{
        int ret;

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

        applesmc_idev = input_allocate_device();
        if (!applesmc_idev) {
                ret = -ENOMEM;
                goto out_sysfs;
        }

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

        /* initialize the input class */
        applesmc_idev->name = "applesmc";
        applesmc_idev->id.bustype = BUS_HOST;
        applesmc_idev->dev.parent = &pdev->dev;
        applesmc_idev->evbit[0] = BIT(EV_ABS);
        applesmc_idev->open = applesmc_idev_open;
        applesmc_idev->close = applesmc_idev_close;
        input_set_abs_params(applesmc_idev, ABS_X,
                        -256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);
        input_set_abs_params(applesmc_idev, ABS_Y,
                        -256, 256, APPLESMC_INPUT_FUZZ, APPLESMC_INPUT_FLAT);

        ret = input_register_device(applesmc_idev);
        if (ret)
                goto out_idev;

        /* start up our timer for the input device */
        init_timer(&applesmc_timer);
        applesmc_timer.function = applesmc_idev_poll;
        applesmc_timer.expires = jiffies + APPLESMC_POLL_PERIOD;

        return 0;

out_idev:
        input_free_device(applesmc_idev);

out_sysfs:
        sysfs_remove_group(&pdev->dev.kobj, &accelerometer_attributes_group);

out:
        printk(KERN_WARNING "applesmc: driver init failed (ret=%d)!\n", ret);
        return ret;
}

/* Release all ressources used by the accelerometer */
static void applesmc_release_accelerometer(void)
{
        del_timer_sync(&applesmc_timer);
        input_unregister_device(applesmc_idev);
        sysfs_remove_group(&pdev->dev.kobj, &accelerometer_attributes_group);
}

static __initdata struct dmi_match_data applesmc_dmi_data[] = {
/* MacBook Pro: accelerometer, backlight and temperature set 0 */
        { .accelerometer = 1, .light = 1, .temperature_set = 0 },
/* MacBook: accelerometer and temperature set 1 */
        { .accelerometer = 1, .light = 0, .temperature_set = 1 },
/* MacMini: temperature set 2 */
        { .accelerometer = 0, .light = 0, .temperature_set = 2 },
};

/* Note that DMI_MATCH(...,"MacBook") will match "MacBookPro1,1".
 * So we need to put "Apple MacBook Pro" before "Apple MacBook". */
static __initdata struct dmi_system_id applesmc_whitelist[] = {
        { applesmc_dmi_match, "Apple MacBook Pro", {
          DMI_MATCH(DMI_BOARD_VENDOR,"Apple"),
          DMI_MATCH(DMI_PRODUCT_NAME,"MacBookPro") },
                (void*)&applesmc_dmi_data[0]},
        { applesmc_dmi_match, "Apple MacBook", {
          DMI_MATCH(DMI_BOARD_VENDOR,"Apple"),
          DMI_MATCH(DMI_PRODUCT_NAME,"MacBook") },
                (void*)&applesmc_dmi_data[1]},
        { applesmc_dmi_match, "Apple Macmini", {
          DMI_MATCH(DMI_BOARD_VENDOR,"Apple"),
          DMI_MATCH(DMI_PRODUCT_NAME,"Macmini") },
                (void*)&applesmc_dmi_data[2]},
        { .ident = NULL }
};

static int __init applesmc_init(void)
{
        int ret;
        int count;
        int i;

        mutex_init(&applesmc_lock);

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

        if (!request_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS,
                                                                "applesmc")) {
                ret = -ENXIO;
                goto out;
        }

        ret = platform_driver_register(&applesmc_driver);
        if (ret)
                goto out_region;

        pdev = platform_device_register_simple("applesmc", APPLESMC_DATA_PORT,
                                               NULL, 0);
        if (IS_ERR(pdev)) {
                ret = PTR_ERR(pdev);
                goto out_driver;
        }

        ret = sysfs_create_file(&pdev->dev.kobj, &dev_attr_name.attr);
        if (ret)
                goto out_device;

        /* Create key enumeration sysfs files */
        ret = sysfs_create_group(&pdev->dev.kobj, &key_enumeration_group);
        if (ret)
                goto out_name;

        /* create fan files */
        count = applesmc_get_fan_count();
        if (count < 0) {
                printk(KERN_ERR "applesmc: Cannot get the number of fans.\n");
        } else {
                printk(KERN_INFO "applesmc: %d fans found.\n", count);

                switch (count) {
                default:
                        printk(KERN_WARNING "applesmc: More than 2 fans found,"
                                        " but at most 2 fans are supported"
                                                " by the driver.\n");
                case 2:
                        ret = sysfs_create_group(&pdev->dev.kobj,
                                                 &fan_attribute_groups[1]);
                        if (ret)
                                goto out_key_enumeration;
                case 1:
                        ret = sysfs_create_group(&pdev->dev.kobj,
                                                 &fan_attribute_groups[0]);
                        if (ret)
                                goto out_fan_1;
                case 0:
                        ;
                }
        }

        for (i = 0;
             temperature_sensors_sets[applesmc_temperature_set][i] != NULL;
             i++) {
                if (temperature_attributes[i] == NULL) {
                        printk(KERN_ERR "applesmc: More temperature sensors "
                                "in temperature_sensors_sets (at least %i)"
                                "than available sysfs files in "
                                "temperature_attributes (%i), please report "
                                "this bug.\n", i, i-1);
                        goto out_temperature;
                }
                ret = sysfs_create_file(&pdev->dev.kobj,
                                                temperature_attributes[i]);
                if (ret)
                        goto out_temperature;
        }

        if (applesmc_accelerometer) {
                ret = applesmc_create_accelerometer();
                if (ret)
                        goto out_temperature;
        }

        if (applesmc_light) {
                /* Add light sensor file */
                ret = sysfs_create_file(&pdev->dev.kobj, &dev_attr_light.attr);
                if (ret)
                        goto out_accelerometer;

                /* Create the workqueue */
                applesmc_led_wq = create_singlethread_workqueue("applesmc-led");
                if (!applesmc_led_wq) {
                        ret = -ENOMEM;
                        goto out_light_sysfs;
                }

                /* register as a led device */
                ret = led_classdev_register(&pdev->dev, &applesmc_backlight);
                if (ret < 0)
                        goto out_light_wq;
        }

        hwmon_class_dev = hwmon_device_register(&pdev->dev);
        if (IS_ERR(hwmon_class_dev)) {
                ret = PTR_ERR(hwmon_class_dev);
                goto out_light_ledclass;
        }

        printk(KERN_INFO "applesmc: driver successfully loaded.\n");

        return 0;

out_light_ledclass:
        if (applesmc_light)
                led_classdev_unregister(&applesmc_backlight);
out_light_wq:
        if (applesmc_light)
                destroy_workqueue(applesmc_led_wq);
out_light_sysfs:
        if (applesmc_light)
                sysfs_remove_file(&pdev->dev.kobj, &dev_attr_light.attr);
out_accelerometer:
        if (applesmc_accelerometer)
                applesmc_release_accelerometer();
out_temperature:
        sysfs_remove_group(&pdev->dev.kobj, &temperature_attributes_group);
        sysfs_remove_group(&pdev->dev.kobj, &fan_attribute_groups[0]);
out_fan_1:
        sysfs_remove_group(&pdev->dev.kobj, &fan_attribute_groups[1]);
out_key_enumeration:
        sysfs_remove_group(&pdev->dev.kobj, &key_enumeration_group);
out_name:
        sysfs_remove_file(&pdev->dev.kobj, &dev_attr_name.attr);
out_device:
        platform_device_unregister(pdev);
out_driver:
        platform_driver_unregister(&applesmc_driver);
out_region:
        release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
out:
        printk(KERN_WARNING "applesmc: driver init failed (ret=%d)!\n", ret);
        return ret;
}

static void __exit applesmc_exit(void)
{
        hwmon_device_unregister(hwmon_class_dev);
        if (applesmc_light) {
                led_classdev_unregister(&applesmc_backlight);
                destroy_workqueue(applesmc_led_wq);
                sysfs_remove_file(&pdev->dev.kobj, &dev_attr_light.attr);
        }
        if (applesmc_accelerometer)
                applesmc_release_accelerometer();
        sysfs_remove_group(&pdev->dev.kobj, &temperature_attributes_group);
        sysfs_remove_group(&pdev->dev.kobj, &fan_attribute_groups[0]);
        sysfs_remove_group(&pdev->dev.kobj, &fan_attribute_groups[1]);
        sysfs_remove_group(&pdev->dev.kobj, &key_enumeration_group);
        sysfs_remove_file(&pdev->dev.kobj, &dev_attr_name.attr);
        platform_device_unregister(pdev);
        platform_driver_unregister(&applesmc_driver);
        release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);

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

module_init(applesmc_init);
module_exit(applesmc_exit);

MODULE_AUTHOR("Nicolas Boichat");
MODULE_DESCRIPTION("Apple SMC");
MODULE_LICENSE("GPL v2");