lm8323.c

Go to the documentation of this file.

/*
 * drivers/i2c/chips/lm8323.c
 *
 * Copyright (C) 2007-2009 Nokia Corporation
 *
 * Written by Daniel Stone <[email protected]>
 *            Timo O. Karjalainen <[email protected]>
 *
 * Updated by Felipe Balbi <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation (version 2 of the License only).
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/input.h>
#include <linux/leds.h>
#include <linux/pm.h>
#include <linux/i2c/lm8323.h>
#include <linux/slab.h>

/* Commands to send to the chip. */
#define LM8323_CMD_READ_ID      0x80 /* Read chip ID. */
#define LM8323_CMD_WRITE_CFG        0x81 /* Set configuration item. */
#define LM8323_CMD_READ_INT     0x82 /* Get interrupt status. */
#define LM8323_CMD_RESET        0x83 /* Reset, same as external one */
#define LM8323_CMD_WRITE_PORT_SEL   0x85 /* Set GPIO in/out. */
#define LM8323_CMD_WRITE_PORT_STATE 0x86 /* Set GPIO pullup. */
#define LM8323_CMD_READ_PORT_SEL    0x87 /* Get GPIO in/out. */
#define LM8323_CMD_READ_PORT_STATE  0x88 /* Get GPIO pullup. */
#define LM8323_CMD_READ_FIFO        0x89 /* Read byte from FIFO. */
#define LM8323_CMD_RPT_READ_FIFO    0x8a /* Read FIFO (no increment). */
#define LM8323_CMD_SET_ACTIVE       0x8b /* Set active time. */
#define LM8323_CMD_READ_ERR     0x8c /* Get error status. */
#define LM8323_CMD_READ_ROTATOR     0x8e /* Read rotator status. */
#define LM8323_CMD_SET_DEBOUNCE     0x8f /* Set debouncing time. */
#define LM8323_CMD_SET_KEY_SIZE     0x90 /* Set keypad size. */
#define LM8323_CMD_READ_KEY_SIZE    0x91 /* Get keypad size. */
#define LM8323_CMD_READ_CFG     0x92 /* Get configuration item. */
#define LM8323_CMD_WRITE_CLOCK      0x93 /* Set clock config. */
#define LM8323_CMD_READ_CLOCK       0x94 /* Get clock config. */
#define LM8323_CMD_PWM_WRITE        0x95 /* Write PWM script. */
#define LM8323_CMD_START_PWM        0x96 /* Start PWM engine. */
#define LM8323_CMD_STOP_PWM     0x97 /* Stop PWM engine. */

/* Interrupt status. */
#define INT_KEYPAD          0x01 /* Key event. */
#define INT_ROTATOR         0x02 /* Rotator event. */
#define INT_ERROR           0x08 /* Error: use CMD_READ_ERR. */
#define INT_NOINIT          0x10 /* Lost configuration. */
#define INT_PWM1            0x20 /* PWM1 stopped. */
#define INT_PWM2            0x40 /* PWM2 stopped. */
#define INT_PWM3            0x80 /* PWM3 stopped. */

/* Errors (signalled by INT_ERROR, read with CMD_READ_ERR). */
#define ERR_BADPAR          0x01 /* Bad parameter. */
#define ERR_CMDUNK          0x02 /* Unknown command. */
#define ERR_KEYOVR          0x04 /* Too many keys pressed. */
#define ERR_FIFOOVER            0x40 /* FIFO overflow. */

/* Configuration keys (CMD_{WRITE,READ}_CFG). */
#define CFG_MUX1SEL         0x01 /* Select MUX1_OUT input. */
#define CFG_MUX1EN          0x02 /* Enable MUX1_OUT. */
#define CFG_MUX2SEL         0x04 /* Select MUX2_OUT input. */
#define CFG_MUX2EN          0x08 /* Enable MUX2_OUT. */
#define CFG_PSIZE           0x20 /* Package size (must be 0). */
#define CFG_ROTEN           0x40 /* Enable rotator. */

/* Clock settings (CMD_{WRITE,READ}_CLOCK). */
#define CLK_RCPWM_INTERNAL      0x00
#define CLK_RCPWM_EXTERNAL      0x03
#define CLK_SLOWCLKEN           0x08 /* Enable 32.768kHz clock. */
#define CLK_SLOWCLKOUT          0x40 /* Enable slow pulse output. */

/* The possible addresses corresponding to CONFIG1 and CONFIG2 pin wirings. */
#define LM8323_I2C_ADDR00       (0x84 >> 1) /* 1000 010x */
#define LM8323_I2C_ADDR01       (0x86 >> 1) /* 1000 011x */
#define LM8323_I2C_ADDR10       (0x88 >> 1) /* 1000 100x */
#define LM8323_I2C_ADDR11       (0x8A >> 1) /* 1000 101x */

/* Key event fifo length */
#define LM8323_FIFO_LEN         15

/* Commands for PWM engine; feed in with PWM_WRITE. */
/* Load ramp counter from duty cycle field (range 0 - 0xff). */
#define PWM_SET(v)          (0x4000 | ((v) & 0xff))
/* Go to start of script. */
#define PWM_GOTOSTART           0x0000
/*
 * Stop engine (generates interrupt).  If reset is 1, clear the program
 * counter, else leave it.
 */
#define PWM_END(reset)          (0xc000 | (!!(reset) << 11))
/*
 * Ramp.  If s is 1, divide clock by 512, else divide clock by 16.
 * Take t clock scales (up to 63) per step, for n steps (up to 126).
 * If u is set, ramp up, else ramp down.
 */
#define PWM_RAMP(s, t, n, u)        ((!!(s) << 14) | ((t) & 0x3f) << 8 | \
                     ((n) & 0x7f) | ((u) ? 0 : 0x80))
/*
 * Loop (i.e. jump back to pos) for a given number of iterations (up to 63).
 * If cnt is zero, execute until PWM_END is encountered.
 */
#define PWM_LOOP(cnt, pos)      (0xa000 | (((cnt) & 0x3f) << 7) | \
                     ((pos) & 0x3f))
/*
 * Wait for trigger.  Argument is a mask of channels, shifted by the channel
 * number, e.g. 0xa for channels 3 and 1.  Note that channels are numbered
 * from 1, not 0.
 */
#define PWM_WAIT_TRIG(chans)        (0xe000 | (((chans) & 0x7) << 6))
/* Send trigger.  Argument is same as PWM_WAIT_TRIG. */
#define PWM_SEND_TRIG(chans)        (0xe000 | ((chans) & 0x7))

struct lm8323_pwm {
    int         id;
    int         fade_time;
    int         brightness;
    int         desired_brightness;
    bool            enabled;
    bool            running;
    /* pwm lock */
    struct mutex        lock;
    struct work_struct  work;
    struct led_classdev cdev;
    struct lm8323_chip  *chip;
};

struct lm8323_chip {
    /* device lock */
    struct mutex        lock;
    struct i2c_client   *client;
    struct input_dev    *idev;
    bool            kp_enabled;
    bool            pm_suspend;
    unsigned        keys_down;
    char            phys[32];
    unsigned short      keymap[LM8323_KEYMAP_SIZE];
    int         size_x;
    int         size_y;
    int         debounce_time;
    int         active_time;
    struct lm8323_pwm   pwm[LM8323_NUM_PWMS];
};

#define client_to_lm8323(c) container_of(c, struct lm8323_chip, client)
#define dev_to_lm8323(d)    container_of(d, struct lm8323_chip, client->dev)
#define cdev_to_pwm(c)      container_of(c, struct lm8323_pwm, cdev)
#define work_to_pwm(w)      container_of(w, struct lm8323_pwm, work)

#define LM8323_MAX_DATA 8

/*
 * To write, we just access the chip's address in write mode, and dump the
 * command and data out on the bus.  The command byte and data are taken as
 * sequential u8s out of varargs, to a maximum of LM8323_MAX_DATA.
 */
static int lm8323_write(struct lm8323_chip *lm, int len, ...)
{
    int ret, i;
    va_list ap;
    u8 data[LM8323_MAX_DATA];

    va_start(ap, len);

    if (unlikely(len > LM8323_MAX_DATA)) {
        dev_err(&lm->client->dev, "tried to send %d bytes\n", len);
        va_end(ap);
        return 0;
    }

    for (i = 0; i < len; i++)
        data[i] = va_arg(ap, int);

    va_end(ap);

    /*
     * If the host is asleep while we send the data, we can get a NACK
     * back while it wakes up, so try again, once.
     */
    ret = i2c_master_send(lm->client, data, len);
    if (unlikely(ret == -EREMOTEIO))
        ret = i2c_master_send(lm->client, data, len);
    if (unlikely(ret != len))
        dev_err(&lm->client->dev, "sent %d bytes of %d total\n",
            len, ret);

    return ret;
}

/*
 * To read, we first send the command byte to the chip and end the transaction,
 * then access the chip in read mode, at which point it will send the data.
 */
static int lm8323_read(struct lm8323_chip *lm, u8 cmd, u8 *buf, int len)
{
    int ret;

    /*
     * If the host is asleep while we send the byte, we can get a NACK
     * back while it wakes up, so try again, once.
     */
    ret = i2c_master_send(lm->client, &cmd, 1);
    if (unlikely(ret == -EREMOTEIO))
        ret = i2c_master_send(lm->client, &cmd, 1);
    if (unlikely(ret != 1)) {
        dev_err(&lm->client->dev, "sending read cmd 0x%02x failed\n",
            cmd);
        return 0;
    }

    ret = i2c_master_recv(lm->client, buf, len);
    if (unlikely(ret != len))
        dev_err(&lm->client->dev, "wanted %d bytes, got %d\n",
            len, ret);

    return ret;
}

/*
 * Set the chip active time (idle time before it enters halt).
 */
static void lm8323_set_active_time(struct lm8323_chip *lm, int time)
{
    lm8323_write(lm, 2, LM8323_CMD_SET_ACTIVE, time >> 2);
}

/*
 * The signals are AT-style: the low 7 bits are the keycode, and the top
 * bit indicates the state (1 for down, 0 for up).
 */
static inline u8 lm8323_whichkey(u8 event)
{
    return event & 0x7f;
}

static inline int lm8323_ispress(u8 event)
{
    return (event & 0x80) ? 1 : 0;
}

static void process_keys(struct lm8323_chip *lm)
{
    u8 event;
    u8 key_fifo[LM8323_FIFO_LEN + 1];
    int old_keys_down = lm->keys_down;
    int ret;
    int i = 0;

    /*
     * Read all key events from the FIFO at once. Next READ_FIFO clears the
     * FIFO even if we didn't read all events previously.
     */
    ret = lm8323_read(lm, LM8323_CMD_READ_FIFO, key_fifo, LM8323_FIFO_LEN);

    if (ret < 0) {
        dev_err(&lm->client->dev, "Failed reading fifo \n");
        return;
    }
    key_fifo[ret] = 0;

    while ((event = key_fifo[i++])) {
        u8 key = lm8323_whichkey(event);
        int isdown = lm8323_ispress(event);
        unsigned short keycode = lm->keymap[key];

        dev_vdbg(&lm->client->dev, "key 0x%02x %s\n",
             key, isdown ? "down" : "up");

        if (lm->kp_enabled) {
            input_event(lm->idev, EV_MSC, MSC_SCAN, key);
            input_report_key(lm->idev, keycode, isdown);
            input_sync(lm->idev);
        }

        if (isdown)
            lm->keys_down++;
        else
            lm->keys_down--;
    }

    /*
     * Errata: We need to ensure that the chip never enters halt mode
     * during a keypress, so set active time to 0.  When it's released,
     * we can enter halt again, so set the active time back to normal.
     */
    if (!old_keys_down && lm->keys_down)
        lm8323_set_active_time(lm, 0);
    if (old_keys_down && !lm->keys_down)
        lm8323_set_active_time(lm, lm->active_time);
}

static void lm8323_process_error(struct lm8323_chip *lm)
{
    u8 error;

    if (lm8323_read(lm, LM8323_CMD_READ_ERR, &error, 1) == 1) {
        if (error & ERR_FIFOOVER)
            dev_vdbg(&lm->client->dev, "fifo overflow!\n");
        if (error & ERR_KEYOVR)
            dev_vdbg(&lm->client->dev,
                    "more than two keys pressed\n");
        if (error & ERR_CMDUNK)
            dev_vdbg(&lm->client->dev,
                    "unknown command submitted\n");
        if (error & ERR_BADPAR)
            dev_vdbg(&lm->client->dev, "bad command parameter\n");
    }
}

static void lm8323_reset(struct lm8323_chip *lm)
{
    /* The docs say we must pass 0xAA as the data byte. */
    lm8323_write(lm, 2, LM8323_CMD_RESET, 0xAA);
}

static int lm8323_configure(struct lm8323_chip *lm)
{
    int keysize = (lm->size_x << 4) | lm->size_y;
    int clock = (CLK_SLOWCLKEN | CLK_RCPWM_EXTERNAL);
    int debounce = lm->debounce_time >> 2;
    int active = lm->active_time >> 2;

    /*
     * Active time must be greater than the debounce time: if it's
     * a close-run thing, give ourselves a 12ms buffer.
     */
    if (debounce >= active)
        active = debounce + 3;

    lm8323_write(lm, 2, LM8323_CMD_WRITE_CFG, 0);
    lm8323_write(lm, 2, LM8323_CMD_WRITE_CLOCK, clock);
    lm8323_write(lm, 2, LM8323_CMD_SET_KEY_SIZE, keysize);
    lm8323_set_active_time(lm, lm->active_time);
    lm8323_write(lm, 2, LM8323_CMD_SET_DEBOUNCE, debounce);
    lm8323_write(lm, 3, LM8323_CMD_WRITE_PORT_STATE, 0xff, 0xff);
    lm8323_write(lm, 3, LM8323_CMD_WRITE_PORT_SEL, 0, 0);

    /*
     * Not much we can do about errors at this point, so just hope
     * for the best.
     */

    return 0;
}

static void pwm_done(struct lm8323_pwm *pwm)
{
    mutex_lock(&pwm->lock);
    pwm->running = false;
    if (pwm->desired_brightness != pwm->brightness)
        schedule_work(&pwm->work);
    mutex_unlock(&pwm->lock);
}

/*
 * Bottom half: handle the interrupt by posting key events, or dealing with
 * errors appropriately.
 */
static irqreturn_t lm8323_irq(int irq, void *_lm)
{
    struct lm8323_chip *lm = _lm;
    u8 ints;
    int i;

    mutex_lock(&lm->lock);

    while ((lm8323_read(lm, LM8323_CMD_READ_INT, &ints, 1) == 1) && ints) {
        if (likely(ints & INT_KEYPAD))
            process_keys(lm);
        if (ints & INT_ROTATOR) {
            /* We don't currently support the rotator. */
            dev_vdbg(&lm->client->dev, "rotator fired\n");
        }
        if (ints & INT_ERROR) {
            dev_vdbg(&lm->client->dev, "error!\n");
            lm8323_process_error(lm);
        }
        if (ints & INT_NOINIT) {
            dev_err(&lm->client->dev, "chip lost config; "
                          "reinitialising\n");
            lm8323_configure(lm);
        }
        for (i = 0; i < LM8323_NUM_PWMS; i++) {
            if (ints & (1 << (INT_PWM1 + i))) {
                dev_vdbg(&lm->client->dev,
                     "pwm%d engine completed\n", i);
                pwm_done(&lm->pwm[i]);
            }
        }
    }

    mutex_unlock(&lm->lock);

    return IRQ_HANDLED;
}

/*
 * Read the chip ID.
 */
static int lm8323_read_id(struct lm8323_chip *lm, u8 *buf)
{
    int bytes;

    bytes = lm8323_read(lm, LM8323_CMD_READ_ID, buf, 2);
    if (unlikely(bytes != 2))
        return -EIO;

    return 0;
}

static void lm8323_write_pwm_one(struct lm8323_pwm *pwm, int pos, u16 cmd)
{
    lm8323_write(pwm->chip, 4, LM8323_CMD_PWM_WRITE, (pos << 2) | pwm->id,
             (cmd & 0xff00) >> 8, cmd & 0x00ff);
}

/*
 * Write a script into a given PWM engine, concluding with PWM_END.
 * If 'kill' is nonzero, the engine will be shut down at the end
 * of the script, producing a zero output. Otherwise the engine
 * will be kept running at the final PWM level indefinitely.
 */
static void lm8323_write_pwm(struct lm8323_pwm *pwm, int kill,
                 int len, const u16 *cmds)
{
    int i;

    for (i = 0; i < len; i++)
        lm8323_write_pwm_one(pwm, i, cmds[i]);

    lm8323_write_pwm_one(pwm, i++, PWM_END(kill));
    lm8323_write(pwm->chip, 2, LM8323_CMD_START_PWM, pwm->id);
    pwm->running = true;
}

static void lm8323_pwm_work(struct work_struct *work)
{
    struct lm8323_pwm *pwm = work_to_pwm(work);
    int div512, perstep, steps, hz, up, kill;
    u16 pwm_cmds[3];
    int num_cmds = 0;

    mutex_lock(&pwm->lock);

    /*
     * Do nothing if we're already at the requested level,
     * or previous setting is not yet complete. In the latter
     * case we will be called again when the previous PWM script
     * finishes.
     */
    if (pwm->running || pwm->desired_brightness == pwm->brightness)
        goto out;

    kill = (pwm->desired_brightness == 0);
    up = (pwm->desired_brightness > pwm->brightness);
    steps = abs(pwm->desired_brightness - pwm->brightness);

    /*
     * Convert time (in ms) into a divisor (512 or 16 on a refclk of
     * 32768Hz), and number of ticks per step.
     */
    if ((pwm->fade_time / steps) > (32768 / 512)) {
        div512 = 1;
        hz = 32768 / 512;
    } else {
        div512 = 0;
        hz = 32768 / 16;
    }

    perstep = (hz * pwm->fade_time) / (steps * 1000);

    if (perstep == 0)
        perstep = 1;
    else if (perstep > 63)
        perstep = 63;

    while (steps) {
        int s;

        s = min(126, steps);
        pwm_cmds[num_cmds++] = PWM_RAMP(div512, perstep, s, up);
        steps -= s;
    }

    lm8323_write_pwm(pwm, kill, num_cmds, pwm_cmds);
    pwm->brightness = pwm->desired_brightness;

 out:
    mutex_unlock(&pwm->lock);
}

static void lm8323_pwm_set_brightness(struct led_classdev *led_cdev,
                      enum led_brightness brightness)
{
    struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
    struct lm8323_chip *lm = pwm->chip;

    mutex_lock(&pwm->lock);
    pwm->desired_brightness = brightness;
    mutex_unlock(&pwm->lock);

    if (in_interrupt()) {
        schedule_work(&pwm->work);
    } else {
        /*
         * Schedule PWM work as usual unless we are going into suspend
         */
        mutex_lock(&lm->lock);
        if (likely(!lm->pm_suspend))
            schedule_work(&pwm->work);
        else
            lm8323_pwm_work(&pwm->work);
        mutex_unlock(&lm->lock);
    }
}

static ssize_t lm8323_pwm_show_time(struct device *dev,
        struct device_attribute *attr, char *buf)
{
    struct led_classdev *led_cdev = dev_get_drvdata(dev);
    struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);

    return sprintf(buf, "%d\n", pwm->fade_time);
}

static ssize_t lm8323_pwm_store_time(struct device *dev,
        struct device_attribute *attr, const char *buf, size_t len)
{
    struct led_classdev *led_cdev = dev_get_drvdata(dev);
    struct lm8323_pwm *pwm = cdev_to_pwm(led_cdev);
    int ret, time;

    ret = kstrtoint(buf, 10, &time);
    /* Numbers only, please. */
    if (ret)
        return ret;

    pwm->fade_time = time;

    return strlen(buf);
}
static DEVICE_ATTR(time, 0644, lm8323_pwm_show_time, lm8323_pwm_store_time);

static int init_pwm(struct lm8323_chip *lm, int id, struct device *dev,
            const char *name)
{
    struct lm8323_pwm *pwm;

    BUG_ON(id > 3);

    pwm = &lm->pwm[id - 1];

    pwm->id = id;
    pwm->fade_time = 0;
    pwm->brightness = 0;
    pwm->desired_brightness = 0;
    pwm->running = false;
    pwm->enabled = false;
    INIT_WORK(&pwm->work, lm8323_pwm_work);
    mutex_init(&pwm->lock);
    pwm->chip = lm;

    if (name) {
        pwm->cdev.name = name;
        pwm->cdev.brightness_set = lm8323_pwm_set_brightness;
        if (led_classdev_register(dev, &pwm->cdev) < 0) {
            dev_err(dev, "couldn't register PWM %d\n", id);
            return -1;
        }
        if (device_create_file(pwm->cdev.dev,
                    &dev_attr_time) < 0) {
            dev_err(dev, "couldn't register time attribute\n");
            led_classdev_unregister(&pwm->cdev);
            return -1;
        }
        pwm->enabled = true;
    }

    return 0;
}

static struct i2c_driver lm8323_i2c_driver;

static ssize_t lm8323_show_disable(struct device *dev,
                   struct device_attribute *attr, char *buf)
{
    struct lm8323_chip *lm = dev_get_drvdata(dev);

    return sprintf(buf, "%u\n", !lm->kp_enabled);
}

static ssize_t lm8323_set_disable(struct device *dev,
                  struct device_attribute *attr,
                  const char *buf, size_t count)
{
    struct lm8323_chip *lm = dev_get_drvdata(dev);
    int ret;
    unsigned int i;

    ret = kstrtouint(buf, 10, &i);

    mutex_lock(&lm->lock);
    lm->kp_enabled = !i;
    mutex_unlock(&lm->lock);

    return count;
}
static DEVICE_ATTR(disable_kp, 0644, lm8323_show_disable, lm8323_set_disable);

static int __devinit lm8323_probe(struct i2c_client *client,
                  const struct i2c_device_id *id)
{
    struct lm8323_platform_data *pdata = client->dev.platform_data;
    struct input_dev *idev;
    struct lm8323_chip *lm;
    int pwm;
    int i, err;
    unsigned long tmo;
    u8 data[2];

    if (!pdata || !pdata->size_x || !pdata->size_y) {
        dev_err(&client->dev, "missing platform_data\n");
        return -EINVAL;
    }

    if (pdata->size_x > 8) {
        dev_err(&client->dev, "invalid x size %d specified\n",
            pdata->size_x);
        return -EINVAL;
    }

    if (pdata->size_y > 12) {
        dev_err(&client->dev, "invalid y size %d specified\n",
            pdata->size_y);
        return -EINVAL;
    }

    lm = kzalloc(sizeof *lm, GFP_KERNEL);
    idev = input_allocate_device();
    if (!lm || !idev) {
        err = -ENOMEM;
        goto fail1;
    }

    lm->client = client;
    lm->idev = idev;
    mutex_init(&lm->lock);

    lm->size_x = pdata->size_x;
    lm->size_y = pdata->size_y;
    dev_vdbg(&client->dev, "Keypad size: %d x %d\n",
         lm->size_x, lm->size_y);

    lm->debounce_time = pdata->debounce_time;
    lm->active_time = pdata->active_time;

    lm8323_reset(lm);

    /* Nothing's set up to service the IRQ yet, so just spin for max.
     * 100ms until we can configure. */
    tmo = jiffies + msecs_to_jiffies(100);
    while (lm8323_read(lm, LM8323_CMD_READ_INT, data, 1) == 1) {
        if (data[0] & INT_NOINIT)
            break;

        if (time_after(jiffies, tmo)) {
            dev_err(&client->dev,
                "timeout waiting for initialisation\n");
            break;
        }

        msleep(1);
    }

    lm8323_configure(lm);

    /* If a true probe check the device */
    if (lm8323_read_id(lm, data) != 0) {
        dev_err(&client->dev, "device not found\n");
        err = -ENODEV;
        goto fail1;
    }

    for (pwm = 0; pwm < LM8323_NUM_PWMS; pwm++) {
        err = init_pwm(lm, pwm + 1, &client->dev,
                   pdata->pwm_names[pwm]);
        if (err < 0)
            goto fail2;
    }

    lm->kp_enabled = true;
    err = device_create_file(&client->dev, &dev_attr_disable_kp);
    if (err < 0)
        goto fail2;

    idev->name = pdata->name ? : "LM8323 keypad";
    snprintf(lm->phys, sizeof(lm->phys),
         "%s/input-kp", dev_name(&client->dev));
    idev->phys = lm->phys;

    idev->evbit[0] = BIT(EV_KEY) | BIT(EV_MSC);
    __set_bit(MSC_SCAN, idev->mscbit);
    for (i = 0; i < LM8323_KEYMAP_SIZE; i++) {
        __set_bit(pdata->keymap[i], idev->keybit);
        lm->keymap[i] = pdata->keymap[i];
    }
    __clear_bit(KEY_RESERVED, idev->keybit);

    if (pdata->repeat)
        __set_bit(EV_REP, idev->evbit);

    err = input_register_device(idev);
    if (err) {
        dev_dbg(&client->dev, "error registering input device\n");
        goto fail3;
    }

    err = request_threaded_irq(client->irq, NULL, lm8323_irq,
              IRQF_TRIGGER_LOW|IRQF_ONESHOT, "lm8323", lm);
    if (err) {
        dev_err(&client->dev, "could not get IRQ %d\n", client->irq);
        goto fail4;
    }

    i2c_set_clientdata(client, lm);

    device_init_wakeup(&client->dev, 1);
    enable_irq_wake(client->irq);

    return 0;

fail4:
    input_unregister_device(idev);
    idev = NULL;
fail3:
    device_remove_file(&client->dev, &dev_attr_disable_kp);
fail2:
    while (--pwm >= 0)
        if (lm->pwm[pwm].enabled) {
            device_remove_file(lm->pwm[pwm].cdev.dev,
                       &dev_attr_time);
            led_classdev_unregister(&lm->pwm[pwm].cdev);
        }
fail1:
    input_free_device(idev);
    kfree(lm);
    return err;
}

static int __devexit lm8323_remove(struct i2c_client *client)
{
    struct lm8323_chip *lm = i2c_get_clientdata(client);
    int i;

    disable_irq_wake(client->irq);
    free_irq(client->irq, lm);

    input_unregister_device(lm->idev);

    device_remove_file(&lm->client->dev, &dev_attr_disable_kp);

    for (i = 0; i < 3; i++)
        if (lm->pwm[i].enabled) {
            device_remove_file(lm->pwm[i].cdev.dev, &dev_attr_time);
            led_classdev_unregister(&lm->pwm[i].cdev);
        }

    kfree(lm);

    return 0;
}

#ifdef CONFIG_PM_SLEEP
/*
 * We don't need to explicitly suspend the chip, as it already switches off
 * when there's no activity.
 */
static int lm8323_suspend(struct device *dev)
{
    struct i2c_client *client = to_i2c_client(dev);
    struct lm8323_chip *lm = i2c_get_clientdata(client);
    int i;

    irq_set_irq_wake(client->irq, 0);
    disable_irq(client->irq);

    mutex_lock(&lm->lock);
    lm->pm_suspend = true;
    mutex_unlock(&lm->lock);

    for (i = 0; i < 3; i++)
        if (lm->pwm[i].enabled)
            led_classdev_suspend(&lm->pwm[i].cdev);

    return 0;
}

static int lm8323_resume(struct device *dev)
{
    struct i2c_client *client = to_i2c_client(dev);
    struct lm8323_chip *lm = i2c_get_clientdata(client);
    int i;

    mutex_lock(&lm->lock);
    lm->pm_suspend = false;
    mutex_unlock(&lm->lock);

    for (i = 0; i < 3; i++)
        if (lm->pwm[i].enabled)
            led_classdev_resume(&lm->pwm[i].cdev);

    enable_irq(client->irq);
    irq_set_irq_wake(client->irq, 1);

    return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(lm8323_pm_ops, lm8323_suspend, lm8323_resume);

static const struct i2c_device_id lm8323_id[] = {
    { "lm8323", 0 },
    { }
};

static struct i2c_driver lm8323_i2c_driver = {
    .driver = {
        .name   = "lm8323",
        .pm = &lm8323_pm_ops,
    },
    .probe      = lm8323_probe,
    .remove     = __devexit_p(lm8323_remove),
    .id_table   = lm8323_id,
};
MODULE_DEVICE_TABLE(i2c, lm8323_id);

module_i2c_driver(lm8323_i2c_driver);

MODULE_AUTHOR("Timo O. Karjalainen <[email protected]>");
MODULE_AUTHOR("Daniel Stone");
MODULE_AUTHOR("Felipe Balbi <[email protected]>");
MODULE_DESCRIPTION("LM8323 keypad driver");
MODULE_LICENSE("GPL");