pmic8xxx-keypad.c

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/* Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 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.
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/mutex.h>

#include <linux/mfd/pm8xxx/core.h>
#include <linux/mfd/pm8xxx/gpio.h>
#include <linux/input/pmic8xxx-keypad.h>

#define PM8XXX_MAX_ROWS     18
#define PM8XXX_MAX_COLS     8
#define PM8XXX_ROW_SHIFT    3
#define PM8XXX_MATRIX_MAX_SIZE  (PM8XXX_MAX_ROWS * PM8XXX_MAX_COLS)

#define PM8XXX_MIN_ROWS     5
#define PM8XXX_MIN_COLS     5

#define MAX_SCAN_DELAY      128
#define MIN_SCAN_DELAY      1

/* in nanoseconds */
#define MAX_ROW_HOLD_DELAY  122000
#define MIN_ROW_HOLD_DELAY  30500

#define MAX_DEBOUNCE_TIME   20
#define MIN_DEBOUNCE_TIME   5

#define KEYP_CTRL           0x148

#define KEYP_CTRL_EVNTS         BIT(0)
#define KEYP_CTRL_EVNTS_MASK        0x3

#define KEYP_CTRL_SCAN_COLS_SHIFT   5
#define KEYP_CTRL_SCAN_COLS_MIN     5
#define KEYP_CTRL_SCAN_COLS_BITS    0x3

#define KEYP_CTRL_SCAN_ROWS_SHIFT   2
#define KEYP_CTRL_SCAN_ROWS_MIN     5
#define KEYP_CTRL_SCAN_ROWS_BITS    0x7

#define KEYP_CTRL_KEYP_EN       BIT(7)

#define KEYP_SCAN           0x149

#define KEYP_SCAN_READ_STATE        BIT(0)
#define KEYP_SCAN_DBOUNCE_SHIFT     1
#define KEYP_SCAN_PAUSE_SHIFT       3
#define KEYP_SCAN_ROW_HOLD_SHIFT    6

#define KEYP_TEST           0x14A

#define KEYP_TEST_CLEAR_RECENT_SCAN BIT(6)
#define KEYP_TEST_CLEAR_OLD_SCAN    BIT(5)
#define KEYP_TEST_READ_RESET        BIT(4)
#define KEYP_TEST_DTEST_EN      BIT(3)
#define KEYP_TEST_ABORT_READ        BIT(0)

#define KEYP_TEST_DBG_SELECT_SHIFT  1

/* bits of these registers represent
 * '0' for key press
 * '1' for key release
 */
#define KEYP_RECENT_DATA        0x14B
#define KEYP_OLD_DATA           0x14C

#define KEYP_CLOCK_FREQ         32768

struct pmic8xxx_kp {
    const struct pm8xxx_keypad_platform_data *pdata;
    struct input_dev *input;
    int key_sense_irq;
    int key_stuck_irq;

    unsigned short keycodes[PM8XXX_MATRIX_MAX_SIZE];

    struct device *dev;
    u16 keystate[PM8XXX_MAX_ROWS];
    u16 stuckstate[PM8XXX_MAX_ROWS];

    u8 ctrl_reg;
};

static int pmic8xxx_kp_write_u8(struct pmic8xxx_kp *kp,
                 u8 data, u16 reg)
{
    int rc;

    rc = pm8xxx_writeb(kp->dev->parent, reg, data);
    return rc;
}

static int pmic8xxx_kp_read(struct pmic8xxx_kp *kp,
                 u8 *data, u16 reg, unsigned num_bytes)
{
    int rc;

    rc = pm8xxx_read_buf(kp->dev->parent, reg, data, num_bytes);
    return rc;
}

static int pmic8xxx_kp_read_u8(struct pmic8xxx_kp *kp,
                 u8 *data, u16 reg)
{
    int rc;

    rc = pmic8xxx_kp_read(kp, data, reg, 1);
    return rc;
}

static u8 pmic8xxx_col_state(struct pmic8xxx_kp *kp, u8 col)
{
    /* all keys pressed on that particular row? */
    if (col == 0x00)
        return 1 << kp->pdata->num_cols;
    else
        return col & ((1 << kp->pdata->num_cols) - 1);
}

/*
 * Synchronous read protocol for RevB0 onwards:
 *
 * 1. Write '1' to ReadState bit in KEYP_SCAN register
 * 2. Wait 2*32KHz clocks, so that HW can successfully enter read mode
 *    synchronously
 * 3. Read rows in old array first if events are more than one
 * 4. Read rows in recent array
 * 5. Wait 4*32KHz clocks
 * 6. Write '0' to ReadState bit of KEYP_SCAN register so that hw can
 *    synchronously exit read mode.
 */
static int pmic8xxx_chk_sync_read(struct pmic8xxx_kp *kp)
{
    int rc;
    u8 scan_val;

    rc = pmic8xxx_kp_read_u8(kp, &scan_val, KEYP_SCAN);
    if (rc < 0) {
        dev_err(kp->dev, "Error reading KEYP_SCAN reg, rc=%d\n", rc);
        return rc;
    }

    scan_val |= 0x1;

    rc = pmic8xxx_kp_write_u8(kp, scan_val, KEYP_SCAN);
    if (rc < 0) {
        dev_err(kp->dev, "Error writing KEYP_SCAN reg, rc=%d\n", rc);
        return rc;
    }

    /* 2 * 32KHz clocks */
    udelay((2 * DIV_ROUND_UP(USEC_PER_SEC, KEYP_CLOCK_FREQ)) + 1);

    return rc;
}

static int pmic8xxx_kp_read_data(struct pmic8xxx_kp *kp, u16 *state,
                    u16 data_reg, int read_rows)
{
    int rc, row;
    u8 new_data[PM8XXX_MAX_ROWS];

    rc = pmic8xxx_kp_read(kp, new_data, data_reg, read_rows);
    if (rc)
        return rc;

    for (row = 0; row < kp->pdata->num_rows; row++) {
        dev_dbg(kp->dev, "new_data[%d] = %d\n", row,
                    new_data[row]);
        state[row] = pmic8xxx_col_state(kp, new_data[row]);
    }

    return rc;
}

static int pmic8xxx_kp_read_matrix(struct pmic8xxx_kp *kp, u16 *new_state,
                     u16 *old_state)
{
    int rc, read_rows;
    u8 scan_val;

    if (kp->pdata->num_rows < PM8XXX_MIN_ROWS)
        read_rows = PM8XXX_MIN_ROWS;
    else
        read_rows = kp->pdata->num_rows;

    pmic8xxx_chk_sync_read(kp);

    if (old_state) {
        rc = pmic8xxx_kp_read_data(kp, old_state, KEYP_OLD_DATA,
                        read_rows);
        if (rc < 0) {
            dev_err(kp->dev,
                "Error reading KEYP_OLD_DATA, rc=%d\n", rc);
            return rc;
        }
    }

    rc = pmic8xxx_kp_read_data(kp, new_state, KEYP_RECENT_DATA,
                     read_rows);
    if (rc < 0) {
        dev_err(kp->dev,
            "Error reading KEYP_RECENT_DATA, rc=%d\n", rc);
        return rc;
    }

    /* 4 * 32KHz clocks */
    udelay((4 * DIV_ROUND_UP(USEC_PER_SEC, KEYP_CLOCK_FREQ)) + 1);

    rc = pmic8xxx_kp_read_u8(kp, &scan_val, KEYP_SCAN);
    if (rc < 0) {
        dev_err(kp->dev, "Error reading KEYP_SCAN reg, rc=%d\n", rc);
        return rc;
    }

    scan_val &= 0xFE;
    rc = pmic8xxx_kp_write_u8(kp, scan_val, KEYP_SCAN);
    if (rc < 0)
        dev_err(kp->dev, "Error writing KEYP_SCAN reg, rc=%d\n", rc);

    return rc;
}

static void __pmic8xxx_kp_scan_matrix(struct pmic8xxx_kp *kp, u16 *new_state,
                     u16 *old_state)
{
    int row, col, code;

    for (row = 0; row < kp->pdata->num_rows; row++) {
        int bits_changed = new_state[row] ^ old_state[row];

        if (!bits_changed)
            continue;

        for (col = 0; col < kp->pdata->num_cols; col++) {
            if (!(bits_changed & (1 << col)))
                continue;

            dev_dbg(kp->dev, "key [%d:%d] %s\n", row, col,
                    !(new_state[row] & (1 << col)) ?
                    "pressed" : "released");

            code = MATRIX_SCAN_CODE(row, col, PM8XXX_ROW_SHIFT);

            input_event(kp->input, EV_MSC, MSC_SCAN, code);
            input_report_key(kp->input,
                    kp->keycodes[code],
                    !(new_state[row] & (1 << col)));

            input_sync(kp->input);
        }
    }
}

static bool pmic8xxx_detect_ghost_keys(struct pmic8xxx_kp *kp, u16 *new_state)
{
    int row, found_first = -1;
    u16 check, row_state;

    check = 0;
    for (row = 0; row < kp->pdata->num_rows; row++) {
        row_state = (~new_state[row]) &
                 ((1 << kp->pdata->num_cols) - 1);

        if (hweight16(row_state) > 1) {
            if (found_first == -1)
                found_first = row;
            if (check & row_state) {
                dev_dbg(kp->dev, "detected ghost key on row[%d]"
                     " and row[%d]\n", found_first, row);
                return true;
            }
        }
        check |= row_state;
    }
    return false;
}

static int pmic8xxx_kp_scan_matrix(struct pmic8xxx_kp *kp, unsigned int events)
{
    u16 new_state[PM8XXX_MAX_ROWS];
    u16 old_state[PM8XXX_MAX_ROWS];
    int rc;

    switch (events) {
    case 0x1:
        rc = pmic8xxx_kp_read_matrix(kp, new_state, NULL);
        if (rc < 0)
            return rc;

        /* detecting ghost key is not an error */
        if (pmic8xxx_detect_ghost_keys(kp, new_state))
            return 0;
        __pmic8xxx_kp_scan_matrix(kp, new_state, kp->keystate);
        memcpy(kp->keystate, new_state, sizeof(new_state));
    break;
    case 0x3: /* two events - eventcounter is gray-coded */
        rc = pmic8xxx_kp_read_matrix(kp, new_state, old_state);
        if (rc < 0)
            return rc;

        __pmic8xxx_kp_scan_matrix(kp, old_state, kp->keystate);
        __pmic8xxx_kp_scan_matrix(kp, new_state, old_state);
        memcpy(kp->keystate, new_state, sizeof(new_state));
    break;
    case 0x2:
        dev_dbg(kp->dev, "Some key events were lost\n");
        rc = pmic8xxx_kp_read_matrix(kp, new_state, old_state);
        if (rc < 0)
            return rc;
        __pmic8xxx_kp_scan_matrix(kp, old_state, kp->keystate);
        __pmic8xxx_kp_scan_matrix(kp, new_state, old_state);
        memcpy(kp->keystate, new_state, sizeof(new_state));
    break;
    default:
        rc = -EINVAL;
    }
    return rc;
}

/*
 * NOTE: We are reading recent and old data registers blindly
 * whenever key-stuck interrupt happens, because events counter doesn't
 * get updated when this interrupt happens due to key stuck doesn't get
 * considered as key state change.
 *
 * We are not using old data register contents after they are being read
 * because it might report the key which was pressed before the key being stuck
 * as stuck key because it's pressed status is stored in the old data
 * register.
 */
static irqreturn_t pmic8xxx_kp_stuck_irq(int irq, void *data)
{
    u16 new_state[PM8XXX_MAX_ROWS];
    u16 old_state[PM8XXX_MAX_ROWS];
    int rc;
    struct pmic8xxx_kp *kp = data;

    rc = pmic8xxx_kp_read_matrix(kp, new_state, old_state);
    if (rc < 0) {
        dev_err(kp->dev, "failed to read keypad matrix\n");
        return IRQ_HANDLED;
    }

    __pmic8xxx_kp_scan_matrix(kp, new_state, kp->stuckstate);

    return IRQ_HANDLED;
}

static irqreturn_t pmic8xxx_kp_irq(int irq, void *data)
{
    struct pmic8xxx_kp *kp = data;
    u8 ctrl_val, events;
    int rc;

    rc = pmic8xxx_kp_read(kp, &ctrl_val, KEYP_CTRL, 1);
    if (rc < 0) {
        dev_err(kp->dev, "failed to read keyp_ctrl register\n");
        return IRQ_HANDLED;
    }

    events = ctrl_val & KEYP_CTRL_EVNTS_MASK;

    rc = pmic8xxx_kp_scan_matrix(kp, events);
    if (rc < 0)
        dev_err(kp->dev, "failed to scan matrix\n");

    return IRQ_HANDLED;
}

static int __devinit pmic8xxx_kpd_init(struct pmic8xxx_kp *kp)
{
    int bits, rc, cycles;
    u8 scan_val = 0, ctrl_val = 0;
    static const u8 row_bits[] = {
        0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 7, 7, 7,
    };

    /* Find column bits */
    if (kp->pdata->num_cols < KEYP_CTRL_SCAN_COLS_MIN)
        bits = 0;
    else
        bits = kp->pdata->num_cols - KEYP_CTRL_SCAN_COLS_MIN;
    ctrl_val = (bits & KEYP_CTRL_SCAN_COLS_BITS) <<
        KEYP_CTRL_SCAN_COLS_SHIFT;

    /* Find row bits */
    if (kp->pdata->num_rows < KEYP_CTRL_SCAN_ROWS_MIN)
        bits = 0;
    else
        bits = row_bits[kp->pdata->num_rows - KEYP_CTRL_SCAN_ROWS_MIN];

    ctrl_val |= (bits << KEYP_CTRL_SCAN_ROWS_SHIFT);

    rc = pmic8xxx_kp_write_u8(kp, ctrl_val, KEYP_CTRL);
    if (rc < 0) {
        dev_err(kp->dev, "Error writing KEYP_CTRL reg, rc=%d\n", rc);
        return rc;
    }

    bits = (kp->pdata->debounce_ms / 5) - 1;

    scan_val |= (bits << KEYP_SCAN_DBOUNCE_SHIFT);

    bits = fls(kp->pdata->scan_delay_ms) - 1;
    scan_val |= (bits << KEYP_SCAN_PAUSE_SHIFT);

    /* Row hold time is a multiple of 32KHz cycles. */
    cycles = (kp->pdata->row_hold_ns * KEYP_CLOCK_FREQ) / NSEC_PER_SEC;

    scan_val |= (cycles << KEYP_SCAN_ROW_HOLD_SHIFT);

    rc = pmic8xxx_kp_write_u8(kp, scan_val, KEYP_SCAN);
    if (rc)
        dev_err(kp->dev, "Error writing KEYP_SCAN reg, rc=%d\n", rc);

    return rc;

}

static int  __devinit pmic8xxx_kp_config_gpio(int gpio_start, int num_gpios,
            struct pmic8xxx_kp *kp, struct pm_gpio *gpio_config)
{
    int rc, i;

    if (gpio_start < 0 || num_gpios < 0)
        return -EINVAL;

    for (i = 0; i < num_gpios; i++) {
        rc = pm8xxx_gpio_config(gpio_start + i, gpio_config);
        if (rc) {
            dev_err(kp->dev, "%s: FAIL pm8xxx_gpio_config():"
                    "for PM GPIO [%d] rc=%d.\n",
                    __func__, gpio_start + i, rc);
            return rc;
        }
     }

    return 0;
}

static int pmic8xxx_kp_enable(struct pmic8xxx_kp *kp)
{
    int rc;

    kp->ctrl_reg |= KEYP_CTRL_KEYP_EN;

    rc = pmic8xxx_kp_write_u8(kp, kp->ctrl_reg, KEYP_CTRL);
    if (rc < 0)
        dev_err(kp->dev, "Error writing KEYP_CTRL reg, rc=%d\n", rc);

    return rc;
}

static int pmic8xxx_kp_disable(struct pmic8xxx_kp *kp)
{
    int rc;

    kp->ctrl_reg &= ~KEYP_CTRL_KEYP_EN;

    rc = pmic8xxx_kp_write_u8(kp, kp->ctrl_reg, KEYP_CTRL);
    if (rc < 0)
        return rc;

    return rc;
}

static int pmic8xxx_kp_open(struct input_dev *dev)
{
    struct pmic8xxx_kp *kp = input_get_drvdata(dev);

    return pmic8xxx_kp_enable(kp);
}

static void pmic8xxx_kp_close(struct input_dev *dev)
{
    struct pmic8xxx_kp *kp = input_get_drvdata(dev);

    pmic8xxx_kp_disable(kp);
}

/*
 * keypad controller should be initialized in the following sequence
 * only, otherwise it might get into FSM stuck state.
 *
 * - Initialize keypad control parameters, like no. of rows, columns,
 *   timing values etc.,
 * - configure rows and column gpios pull up/down.
 * - set irq edge type.
 * - enable the keypad controller.
 */
static int __devinit pmic8xxx_kp_probe(struct platform_device *pdev)
{
    const struct pm8xxx_keypad_platform_data *pdata =
                    dev_get_platdata(&pdev->dev);
    const struct matrix_keymap_data *keymap_data;
    struct pmic8xxx_kp *kp;
    int rc;
    u8 ctrl_val;

    struct pm_gpio kypd_drv = {
        .direction  = PM_GPIO_DIR_OUT,
        .output_buffer  = PM_GPIO_OUT_BUF_OPEN_DRAIN,
        .output_value   = 0,
        .pull       = PM_GPIO_PULL_NO,
        .vin_sel    = PM_GPIO_VIN_S3,
        .out_strength   = PM_GPIO_STRENGTH_LOW,
        .function   = PM_GPIO_FUNC_1,
        .inv_int_pol    = 1,
    };

    struct pm_gpio kypd_sns = {
        .direction  = PM_GPIO_DIR_IN,
        .pull       = PM_GPIO_PULL_UP_31P5,
        .vin_sel    = PM_GPIO_VIN_S3,
        .out_strength   = PM_GPIO_STRENGTH_NO,
        .function   = PM_GPIO_FUNC_NORMAL,
        .inv_int_pol    = 1,
    };


    if (!pdata || !pdata->num_cols || !pdata->num_rows ||
        pdata->num_cols > PM8XXX_MAX_COLS ||
        pdata->num_rows > PM8XXX_MAX_ROWS ||
        pdata->num_cols < PM8XXX_MIN_COLS) {
        dev_err(&pdev->dev, "invalid platform data\n");
        return -EINVAL;
    }

    if (!pdata->scan_delay_ms ||
        pdata->scan_delay_ms > MAX_SCAN_DELAY ||
        pdata->scan_delay_ms < MIN_SCAN_DELAY ||
        !is_power_of_2(pdata->scan_delay_ms)) {
        dev_err(&pdev->dev, "invalid keypad scan time supplied\n");
        return -EINVAL;
    }

    if (!pdata->row_hold_ns ||
        pdata->row_hold_ns > MAX_ROW_HOLD_DELAY ||
        pdata->row_hold_ns < MIN_ROW_HOLD_DELAY ||
        ((pdata->row_hold_ns % MIN_ROW_HOLD_DELAY) != 0)) {
        dev_err(&pdev->dev, "invalid keypad row hold time supplied\n");
        return -EINVAL;
    }

    if (!pdata->debounce_ms ||
        ((pdata->debounce_ms % 5) != 0) ||
        pdata->debounce_ms > MAX_DEBOUNCE_TIME ||
        pdata->debounce_ms < MIN_DEBOUNCE_TIME) {
        dev_err(&pdev->dev, "invalid debounce time supplied\n");
        return -EINVAL;
    }

    keymap_data = pdata->keymap_data;
    if (!keymap_data) {
        dev_err(&pdev->dev, "no keymap data supplied\n");
        return -EINVAL;
    }

    kp = kzalloc(sizeof(*kp), GFP_KERNEL);
    if (!kp)
        return -ENOMEM;

    platform_set_drvdata(pdev, kp);

    kp->pdata   = pdata;
    kp->dev     = &pdev->dev;

    kp->input = input_allocate_device();
    if (!kp->input) {
        dev_err(&pdev->dev, "unable to allocate input device\n");
        rc = -ENOMEM;
        goto err_alloc_device;
    }

    kp->key_sense_irq = platform_get_irq(pdev, 0);
    if (kp->key_sense_irq < 0) {
        dev_err(&pdev->dev, "unable to get keypad sense irq\n");
        rc = -ENXIO;
        goto err_get_irq;
    }

    kp->key_stuck_irq = platform_get_irq(pdev, 1);
    if (kp->key_stuck_irq < 0) {
        dev_err(&pdev->dev, "unable to get keypad stuck irq\n");
        rc = -ENXIO;
        goto err_get_irq;
    }

    kp->input->name = pdata->input_name ? : "PMIC8XXX keypad";
    kp->input->phys = pdata->input_phys_device ? : "pmic8xxx_keypad/input0";

    kp->input->dev.parent   = &pdev->dev;

    kp->input->id.bustype   = BUS_I2C;
    kp->input->id.version   = 0x0001;
    kp->input->id.product   = 0x0001;
    kp->input->id.vendor    = 0x0001;

    kp->input->open     = pmic8xxx_kp_open;
    kp->input->close    = pmic8xxx_kp_close;

    rc = matrix_keypad_build_keymap(keymap_data, NULL,
                    PM8XXX_MAX_ROWS, PM8XXX_MAX_COLS,
                    kp->keycodes, kp->input);
    if (rc) {
        dev_err(&pdev->dev, "failed to build keymap\n");
        goto err_get_irq;
    }

    if (pdata->rep)
        __set_bit(EV_REP, kp->input->evbit);
    input_set_capability(kp->input, EV_MSC, MSC_SCAN);

    input_set_drvdata(kp->input, kp);

    /* initialize keypad state */
    memset(kp->keystate, 0xff, sizeof(kp->keystate));
    memset(kp->stuckstate, 0xff, sizeof(kp->stuckstate));

    rc = pmic8xxx_kpd_init(kp);
    if (rc < 0) {
        dev_err(&pdev->dev, "unable to initialize keypad controller\n");
        goto err_get_irq;
    }

    rc = pmic8xxx_kp_config_gpio(pdata->cols_gpio_start,
                    pdata->num_cols, kp, &kypd_sns);
    if (rc < 0) {
        dev_err(&pdev->dev, "unable to configure keypad sense lines\n");
        goto err_gpio_config;
    }

    rc = pmic8xxx_kp_config_gpio(pdata->rows_gpio_start,
                    pdata->num_rows, kp, &kypd_drv);
    if (rc < 0) {
        dev_err(&pdev->dev, "unable to configure keypad drive lines\n");
        goto err_gpio_config;
    }

    rc = request_any_context_irq(kp->key_sense_irq, pmic8xxx_kp_irq,
                 IRQF_TRIGGER_RISING, "pmic-keypad", kp);
    if (rc < 0) {
        dev_err(&pdev->dev, "failed to request keypad sense irq\n");
        goto err_get_irq;
    }

    rc = request_any_context_irq(kp->key_stuck_irq, pmic8xxx_kp_stuck_irq,
                 IRQF_TRIGGER_RISING, "pmic-keypad-stuck", kp);
    if (rc < 0) {
        dev_err(&pdev->dev, "failed to request keypad stuck irq\n");
        goto err_req_stuck_irq;
    }

    rc = pmic8xxx_kp_read_u8(kp, &ctrl_val, KEYP_CTRL);
    if (rc < 0) {
        dev_err(&pdev->dev, "failed to read KEYP_CTRL register\n");
        goto err_pmic_reg_read;
    }

    kp->ctrl_reg = ctrl_val;

    rc = input_register_device(kp->input);
    if (rc < 0) {
        dev_err(&pdev->dev, "unable to register keypad input device\n");
        goto err_pmic_reg_read;
    }

    device_init_wakeup(&pdev->dev, pdata->wakeup);

    return 0;

err_pmic_reg_read:
    free_irq(kp->key_stuck_irq, kp);
err_req_stuck_irq:
    free_irq(kp->key_sense_irq, kp);
err_gpio_config:
err_get_irq:
    input_free_device(kp->input);
err_alloc_device:
    platform_set_drvdata(pdev, NULL);
    kfree(kp);
    return rc;
}

static int __devexit pmic8xxx_kp_remove(struct platform_device *pdev)
{
    struct pmic8xxx_kp *kp = platform_get_drvdata(pdev);

    device_init_wakeup(&pdev->dev, 0);
    free_irq(kp->key_stuck_irq, kp);
    free_irq(kp->key_sense_irq, kp);
    input_unregister_device(kp->input);
    kfree(kp);

    platform_set_drvdata(pdev, NULL);
    return 0;
}

#ifdef CONFIG_PM_SLEEP
static int pmic8xxx_kp_suspend(struct device *dev)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct pmic8xxx_kp *kp = platform_get_drvdata(pdev);
    struct input_dev *input_dev = kp->input;

    if (device_may_wakeup(dev)) {
        enable_irq_wake(kp->key_sense_irq);
    } else {
        mutex_lock(&input_dev->mutex);

        if (input_dev->users)
            pmic8xxx_kp_disable(kp);

        mutex_unlock(&input_dev->mutex);
    }

    return 0;
}

static int pmic8xxx_kp_resume(struct device *dev)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct pmic8xxx_kp *kp = platform_get_drvdata(pdev);
    struct input_dev *input_dev = kp->input;

    if (device_may_wakeup(dev)) {
        disable_irq_wake(kp->key_sense_irq);
    } else {
        mutex_lock(&input_dev->mutex);

        if (input_dev->users)
            pmic8xxx_kp_enable(kp);

        mutex_unlock(&input_dev->mutex);
    }

    return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(pm8xxx_kp_pm_ops,
             pmic8xxx_kp_suspend, pmic8xxx_kp_resume);

static struct platform_driver pmic8xxx_kp_driver = {
    .probe      = pmic8xxx_kp_probe,
    .remove     = __devexit_p(pmic8xxx_kp_remove),
    .driver     = {
        .name = PM8XXX_KEYPAD_DEV_NAME,
        .owner = THIS_MODULE,
        .pm = &pm8xxx_kp_pm_ops,
    },
};
module_platform_driver(pmic8xxx_kp_driver);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("PMIC8XXX keypad driver");
MODULE_VERSION("1.0");
MODULE_ALIAS("platform:pmic8xxx_keypad");
MODULE_AUTHOR("Trilok Soni <[email protected]>");