/*
 * linux/drivers/input/keyboard/pxa27x_keypad.c
 *
 * Driver for the pxa27x matrix keyboard controller.
 *
 * Created:     Feb 22, 2007
 * Author:      Rodolfo Giometti <giometti@linux.it>
 *
 * Based on a previous implementations by Kevin O'Connor
 * <kevin_at_koconnor.net> and Alex Osborne <bobofdoom@gmail.com> and
 * on some suggestions by Nicolas Pitre <nico@fluxnic.net>.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */


#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/io.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/input/matrix_keypad.h>
#include <linux/slab.h>
#include <linux/of.h>

#include <linux/platform_data/keypad-pxa27x.h>
/*
 * Keypad Controller registers
 */
#define KPC             0x0000 /* Keypad Control register */
#define KPDK            0x0008 /* Keypad Direct Key register */
#define KPREC           0x0010 /* Keypad Rotary Encoder register */
#define KPMK            0x0018 /* Keypad Matrix Key register */
#define KPAS            0x0020 /* Keypad Automatic Scan register */

/* Keypad Automatic Scan Multiple Key Presser register 0-3 */
#define KPASMKP0        0x0028
#define KPASMKP1        0x0030
#define KPASMKP2        0x0038
#define KPASMKP3        0x0040
#define KPKDI           0x0048

/* bit definitions */
#define KPC_MKRN(n)     ((((n) - 1) & 0x7) << 26) /* matrix key row number */
#define KPC_MKCN(n)     ((((n) - 1) & 0x7) << 23) /* matrix key column number */
#define KPC_DKN(n)      ((((n) - 1) & 0x7) << 6)  /* direct key number */

#define KPC_AS          (0x1 << 30)  /* Automatic Scan bit */
#define KPC_ASACT       (0x1 << 29)  /* Automatic Scan on Activity */
#define KPC_MI          (0x1 << 22)  /* Matrix interrupt bit */
#define KPC_IMKP        (0x1 << 21)  /* Ignore Multiple Key Press */

#define KPC_MS(n)       (0x1 << (13 + (n)))     /* Matrix scan line 'n' */
#define KPC_MS_ALL      (0xff << 13)

#define KPC_ME          (0x1 << 12)  /* Matrix Keypad Enable */
#define KPC_MIE         (0x1 << 11)  /* Matrix Interrupt Enable */
#define KPC_DK_DEB_SEL  (0x1 <<  9)  /* Direct Keypad Debounce Select */
#define KPC_DI          (0x1 <<  5)  /* Direct key interrupt bit */
#define KPC_RE_ZERO_DEB (0x1 <<  4)  /* Rotary Encoder Zero Debounce */
#define KPC_REE1        (0x1 <<  3)  /* Rotary Encoder1 Enable */
#define KPC_REE0        (0x1 <<  2)  /* Rotary Encoder0 Enable */
#define KPC_DE          (0x1 <<  1)  /* Direct Keypad Enable */
#define KPC_DIE         (0x1 <<  0)  /* Direct Keypad interrupt Enable */

#define KPDK_DKP        (0x1 << 31)
#define KPDK_DK(n)      ((n) & 0xff)

#define KPREC_OF1       (0x1 << 31)
#define kPREC_UF1       (0x1 << 30)
#define KPREC_OF0       (0x1 << 15)
#define KPREC_UF0       (0x1 << 14)

#define KPREC_RECOUNT0(n)       ((n) & 0xff)
#define KPREC_RECOUNT1(n)       (((n) >> 16) & 0xff)

#define KPMK_MKP        (0x1 << 31)
#define KPAS_SO         (0x1 << 31)
#define KPASMKPx_SO     (0x1 << 31)

#define KPAS_MUKP(n)    (((n) >> 26) & 0x1f)
#define KPAS_RP(n)      (((n) >> 4) & 0xf)
#define KPAS_CP(n)      ((n) & 0xf)

#define KPASMKP_MKC_MASK        (0xff)

#define keypad_readl(off)       __raw_readl(keypad->mmio_base + (off))
#define keypad_writel(off, v)   __raw_writel((v), keypad->mmio_base + (off))

#define MAX_MATRIX_KEY_NUM      (MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
#define MAX_KEYPAD_KEYS         (MAX_MATRIX_KEY_NUM + MAX_DIRECT_KEY_NUM)

struct pxa27x_keypad {
        const struct pxa27x_keypad_platform_data *pdata;

        struct clk *clk;
        struct input_dev *input_dev;
        void __iomem *mmio_base;

        int irq;

        unsigned short keycodes[MAX_KEYPAD_KEYS];
        int rotary_rel_code[2];

        unsigned int row_shift;

        /* state row bits of each column scan */
        uint32_t matrix_key_state[MAX_MATRIX_KEY_COLS];
        uint32_t direct_key_state;

        unsigned int direct_key_mask;
};

#ifdef CONFIG_OF
static int pxa27x_keypad_matrix_key_parse_dt(struct pxa27x_keypad *keypad,
                                struct pxa27x_keypad_platform_data *pdata)
{
        struct input_dev *input_dev = keypad->input_dev;
        struct device *dev = input_dev->dev.parent;
        u32 rows, cols;
        int error;

        error = matrix_keypad_parse_properties(dev, &rows, &cols);
        if (error)
                return error;

        if (rows > MAX_MATRIX_KEY_ROWS || cols > MAX_MATRIX_KEY_COLS) {
                dev_err(dev, "rows or cols exceeds maximum value\n");
                return -EINVAL;
        }

        pdata->matrix_key_rows = rows;
        pdata->matrix_key_cols = cols;

        error = matrix_keypad_build_keymap(NULL, NULL,
                                           pdata->matrix_key_rows,
                                           pdata->matrix_key_cols,
                                           keypad->keycodes, input_dev);
        if (error)
                return error;

        return 0;
}

static int pxa27x_keypad_direct_key_parse_dt(struct pxa27x_keypad *keypad,
                                struct pxa27x_keypad_platform_data *pdata)
{
        struct input_dev *input_dev = keypad->input_dev;
        struct device *dev = input_dev->dev.parent;
        struct device_node *np = dev->of_node;
        const __be16 *prop;
        unsigned short code;
        unsigned int proplen, size;
        int i;
        int error;

        error = of_property_read_u32(np, "marvell,direct-key-count",
                                     &pdata->direct_key_num);
        if (error) {
                /*
                 * If do not have marvel,direct-key-count defined,
                 * it means direct key is not supported.
                 */
                return error == -EINVAL ? 0 : error;
        }

        error = of_property_read_u32(np, "marvell,direct-key-mask",
                                     &pdata->direct_key_mask);
        if (error) {
                if (error != -EINVAL)
                        return error;

                /*
                 * If marvell,direct-key-mask is not defined, driver will use
                 * default value. Default value is set when configure the keypad.
                 */
                pdata->direct_key_mask = 0;
        }

        pdata->direct_key_low_active = of_property_read_bool(np,
                                        "marvell,direct-key-low-active");

        prop = of_get_property(np, "marvell,direct-key-map", &proplen);
        if (!prop)
                return -EINVAL;

        if (proplen % sizeof(u16))
                return -EINVAL;

        size = proplen / sizeof(u16);

        /* Only MAX_DIRECT_KEY_NUM is accepted.*/
        if (size > MAX_DIRECT_KEY_NUM)
                return -EINVAL;

        for (i = 0; i < size; i++) {
                code = be16_to_cpup(prop + i);
                keypad->keycodes[MAX_MATRIX_KEY_NUM + i] = code;
                __set_bit(code, input_dev->keybit);
        }

        return 0;
}

static int pxa27x_keypad_rotary_parse_dt(struct pxa27x_keypad *keypad,
                                struct pxa27x_keypad_platform_data *pdata)
{
        const __be32 *prop;
        int i, relkey_ret;
        unsigned int code, proplen;
        const char *rotaryname[2] = {
                        "marvell,rotary0", "marvell,rotary1"};
        const char relkeyname[] = {"marvell,rotary-rel-key"};
        struct input_dev *input_dev = keypad->input_dev;
        struct device *dev = input_dev->dev.parent;
        struct device_node *np = dev->of_node;

        relkey_ret = of_property_read_u32(np, relkeyname, &code);
        /* if can read correct rotary key-code, we do not need this. */
        if (relkey_ret == 0) {
                unsigned short relcode;

                /* rotary0 taks lower half, rotary1 taks upper half. */
                relcode = code & 0xffff;
                pdata->rotary0_rel_code = (code & 0xffff);
                __set_bit(relcode, input_dev->relbit);

                relcode = code >> 16;
                pdata->rotary1_rel_code = relcode;
                __set_bit(relcode, input_dev->relbit);
        }

        for (i = 0; i < 2; i++) {
                prop = of_get_property(np, rotaryname[i], &proplen);
                /*
                 * If the prop is not set, it means keypad does not need
                 * initialize the rotaryX.
                 */
                if (!prop)
                        continue;

                code = be32_to_cpup(prop);
                /*
                 * Not all up/down key code are valid.
                 * Now we depends on direct-rel-code.
                 */
                if ((!(code & 0xffff) || !(code >> 16)) && relkey_ret) {
                        return relkey_ret;
                } else {
                        unsigned int n = MAX_MATRIX_KEY_NUM + (i << 1);
                        unsigned short keycode;

                        keycode = code & 0xffff;
                        keypad->keycodes[n] = keycode;
                        __set_bit(keycode, input_dev->keybit);

                        keycode = code >> 16;
                        keypad->keycodes[n + 1] = keycode;
                        __set_bit(keycode, input_dev->keybit);

                        if (i == 0)
                                pdata->rotary0_rel_code = -1;
                        else
                                pdata->rotary1_rel_code = -1;
                }
                if (i == 0)
                        pdata->enable_rotary0 = 1;
                else
                        pdata->enable_rotary1 = 1;
        }

        keypad->rotary_rel_code[0] = pdata->rotary0_rel_code;
        keypad->rotary_rel_code[1] = pdata->rotary1_rel_code;

        return 0;
}

static int pxa27x_keypad_build_keycode_from_dt(struct pxa27x_keypad *keypad)
{
        struct input_dev *input_dev = keypad->input_dev;
        struct device *dev = input_dev->dev.parent;
        struct device_node *np = dev->of_node;
        struct pxa27x_keypad_platform_data *pdata;
        int error;

        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
        if (!pdata) {
                dev_err(dev, "failed to allocate memory for pdata\n");
                return -ENOMEM;
        }

        error = pxa27x_keypad_matrix_key_parse_dt(keypad, pdata);
        if (error) {
                dev_err(dev, "failed to parse matrix key\n");
                return error;
        }

        error = pxa27x_keypad_direct_key_parse_dt(keypad, pdata);
        if (error) {
                dev_err(dev, "failed to parse direct key\n");
                return error;
        }

        error = pxa27x_keypad_rotary_parse_dt(keypad, pdata);
        if (error) {
                dev_err(dev, "failed to parse rotary key\n");
                return error;
        }

        error = of_property_read_u32(np, "marvell,debounce-interval",
                                     &pdata->debounce_interval);
        if (error) {
                dev_err(dev, "failed to parse debounce-interval\n");
                return error;
        }

        /*
         * The keycodes may not only includes matrix key but also the direct
         * key or rotary key.
         */
        input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);

        keypad->pdata = pdata;
        return 0;
}

#else

static int pxa27x_keypad_build_keycode_from_dt(struct pxa27x_keypad *keypad)
{
        dev_info(keypad->input_dev->dev.parent, "missing platform data\n");

        return -EINVAL;
}

#endif

static int pxa27x_keypad_build_keycode(struct pxa27x_keypad *keypad)
{
        const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
        struct input_dev *input_dev = keypad->input_dev;
        unsigned short keycode;
        int i;
        int error;

        error = matrix_keypad_build_keymap(pdata->matrix_keymap_data, NULL,
                                           pdata->matrix_key_rows,
                                           pdata->matrix_key_cols,
                                           keypad->keycodes, input_dev);
        if (error)
                return error;

        /*
         * The keycodes may not only include matrix keys but also the direct
         * or rotary keys.
         */
        input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);

        /* For direct keys. */
        for (i = 0; i < pdata->direct_key_num; i++) {
                keycode = pdata->direct_key_map[i];
                keypad->keycodes[MAX_MATRIX_KEY_NUM + i] = keycode;
                __set_bit(keycode, input_dev->keybit);
        }

        if (pdata->enable_rotary0) {
                if (pdata->rotary0_up_key && pdata->rotary0_down_key) {
                        keycode = pdata->rotary0_up_key;
                        keypad->keycodes[MAX_MATRIX_KEY_NUM + 0] = keycode;
                        __set_bit(keycode, input_dev->keybit);

                        keycode = pdata->rotary0_down_key;
                        keypad->keycodes[MAX_MATRIX_KEY_NUM + 1] = keycode;
                        __set_bit(keycode, input_dev->keybit);

                        keypad->rotary_rel_code[0] = -1;
                } else {
                        keypad->rotary_rel_code[0] = pdata->rotary0_rel_code;
                        __set_bit(pdata->rotary0_rel_code, input_dev->relbit);
                }
        }

        if (pdata->enable_rotary1) {
                if (pdata->rotary1_up_key && pdata->rotary1_down_key) {
                        keycode = pdata->rotary1_up_key;
                        keypad->keycodes[MAX_MATRIX_KEY_NUM + 2] = keycode;
                        __set_bit(keycode, input_dev->keybit);

                        keycode = pdata->rotary1_down_key;
                        keypad->keycodes[MAX_MATRIX_KEY_NUM + 3] = keycode;
                        __set_bit(keycode, input_dev->keybit);

                        keypad->rotary_rel_code[1] = -1;
                } else {
                        keypad->rotary_rel_code[1] = pdata->rotary1_rel_code;
                        __set_bit(pdata->rotary1_rel_code, input_dev->relbit);
                }
        }

        __clear_bit(KEY_RESERVED, input_dev->keybit);

        return 0;
}

static void pxa27x_keypad_scan_matrix(struct pxa27x_keypad *keypad)
{
        const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
        struct input_dev *input_dev = keypad->input_dev;
        int row, col, num_keys_pressed = 0;
        uint32_t new_state[MAX_MATRIX_KEY_COLS];
        uint32_t kpas = keypad_readl(KPAS);

        num_keys_pressed = KPAS_MUKP(kpas);

        memset(new_state, 0, sizeof(new_state));

        if (num_keys_pressed == 0)
                goto scan;

        if (num_keys_pressed == 1) {
                col = KPAS_CP(kpas);
                row = KPAS_RP(kpas);

                /* if invalid row/col, treat as no key pressed */
                if (col >= pdata->matrix_key_cols ||
                    row >= pdata->matrix_key_rows)
                        goto scan;

                new_state[col] = (1 << row);
                goto scan;
        }

        if (num_keys_pressed > 1) {
                uint32_t kpasmkp0 = keypad_readl(KPASMKP0);
                uint32_t kpasmkp1 = keypad_readl(KPASMKP1);
                uint32_t kpasmkp2 = keypad_readl(KPASMKP2);
                uint32_t kpasmkp3 = keypad_readl(KPASMKP3);

                new_state[0] = kpasmkp0 & KPASMKP_MKC_MASK;
                new_state[1] = (kpasmkp0 >> 16) & KPASMKP_MKC_MASK;
                new_state[2] = kpasmkp1 & KPASMKP_MKC_MASK;
                new_state[3] = (kpasmkp1 >> 16) & KPASMKP_MKC_MASK;
                new_state[4] = kpasmkp2 & KPASMKP_MKC_MASK;
                new_state[5] = (kpasmkp2 >> 16) & KPASMKP_MKC_MASK;
                new_state[6] = kpasmkp3 & KPASMKP_MKC_MASK;
                new_state[7] = (kpasmkp3 >> 16) & KPASMKP_MKC_MASK;
        }
scan:
        for (col = 0; col < pdata->matrix_key_cols; col++) {
                uint32_t bits_changed;
                int code;

                bits_changed = keypad->matrix_key_state[col] ^ new_state[col];
                if (bits_changed == 0)
                        continue;

                for (row = 0; row < pdata->matrix_key_rows; row++) {
                        if ((bits_changed & (1 << row)) == 0)
                                continue;

                        code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);

                        input_event(input_dev, EV_MSC, MSC_SCAN, code);
                        input_report_key(input_dev, keypad->keycodes[code],
                                         new_state[col] & (1 << row));
                }
        }
        input_sync(input_dev);
        memcpy(keypad->matrix_key_state, new_state, sizeof(new_state));
}

#define DEFAULT_KPREC   (0x007f007f)

static inline int rotary_delta(uint32_t kprec)
{
        if (kprec & KPREC_OF0)
                return (kprec & 0xff) + 0x7f;
        else if (kprec & KPREC_UF0)
                return (kprec & 0xff) - 0x7f - 0xff;
        else
                return (kprec & 0xff) - 0x7f;
}

static void report_rotary_event(struct pxa27x_keypad *keypad, int r, int delta)
{
        struct input_dev *dev = keypad->input_dev;

        if (delta == 0)
                return;

        if (keypad->rotary_rel_code[r] == -1) {
                int code = MAX_MATRIX_KEY_NUM + 2 * r + (delta > 0 ? 0 : 1);
                unsigned char keycode = keypad->keycodes[code];

                /* simulate a press-n-release */
                input_event(dev, EV_MSC, MSC_SCAN, code);
                input_report_key(dev, keycode, 1);
                input_sync(dev);
                input_event(dev, EV_MSC, MSC_SCAN, code);
                input_report_key(dev, keycode, 0);
                input_sync(dev);
        } else {
                input_report_rel(dev, keypad->rotary_rel_code[r], delta);
                input_sync(dev);
        }
}

static void pxa27x_keypad_scan_rotary(struct pxa27x_keypad *keypad)
{
        const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
        uint32_t kprec;

        /* read and reset to default count value */
        kprec = keypad_readl(KPREC);
        keypad_writel(KPREC, DEFAULT_KPREC);

        if (pdata->enable_rotary0)
                report_rotary_event(keypad, 0, rotary_delta(kprec));

        if (pdata->enable_rotary1)
                report_rotary_event(keypad, 1, rotary_delta(kprec >> 16));
}

static void pxa27x_keypad_scan_direct(struct pxa27x_keypad *keypad)
{
        const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
        struct input_dev *input_dev = keypad->input_dev;
        unsigned int new_state;
        uint32_t kpdk, bits_changed;
        int i;

        kpdk = keypad_readl(KPDK);

        if (pdata->enable_rotary0 || pdata->enable_rotary1)
                pxa27x_keypad_scan_rotary(keypad);

        /*
         * The KPDR_DK only output the key pin level, so it relates to board,
         * and low level may be active.
         */
        if (pdata->direct_key_low_active)
                new_state = ~KPDK_DK(kpdk) & keypad->direct_key_mask;
        else
                new_state = KPDK_DK(kpdk) & keypad->direct_key_mask;

        bits_changed = keypad->direct_key_state ^ new_state;

        if (bits_changed == 0)
                return;

        for (i = 0; i < pdata->direct_key_num; i++) {
                if (bits_changed & (1 << i)) {
                        int code = MAX_MATRIX_KEY_NUM + i;

                        input_event(input_dev, EV_MSC, MSC_SCAN, code);
                        input_report_key(input_dev, keypad->keycodes[code],
                                         new_state & (1 << i));
                }
        }
        input_sync(input_dev);
        keypad->direct_key_state = new_state;
}

static void clear_wakeup_event(struct pxa27x_keypad *keypad)
{
        const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;

        if (pdata->clear_wakeup_event)
                (pdata->clear_wakeup_event)();
}

static irqreturn_t pxa27x_keypad_irq_handler(int irq, void *dev_id)
{
        struct pxa27x_keypad *keypad = dev_id;
        unsigned long kpc = keypad_readl(KPC);

        clear_wakeup_event(keypad);

        if (kpc & KPC_DI)
                pxa27x_keypad_scan_direct(keypad);

        if (kpc & KPC_MI)
                pxa27x_keypad_scan_matrix(keypad);

        return IRQ_HANDLED;
}

static void pxa27x_keypad_config(struct pxa27x_keypad *keypad)
{
        const struct pxa27x_keypad_platform_data *pdata = keypad->pdata;
        unsigned int mask = 0, direct_key_num = 0;
        unsigned long kpc = 0;

        /* clear pending interrupt bit */
        keypad_readl(KPC);

        /* enable matrix keys with automatic scan */
        if (pdata->matrix_key_rows && pdata->matrix_key_cols) {
                kpc |= KPC_ASACT | KPC_MIE | KPC_ME | KPC_MS_ALL;
                kpc |= KPC_MKRN(pdata->matrix_key_rows) |
                       KPC_MKCN(pdata->matrix_key_cols);
        }

        /* enable rotary key, debounce interval same as direct keys */
        if (pdata->enable_rotary0) {
                mask |= 0x03;
                direct_key_num = 2;
                kpc |= KPC_REE0;
        }

        if (pdata->enable_rotary1) {
                mask |= 0x0c;
                direct_key_num = 4;
                kpc |= KPC_REE1;
        }

        if (pdata->direct_key_num > direct_key_num)
                direct_key_num = pdata->direct_key_num;

        /*
         * Direct keys usage may not start from KP_DKIN0, check the platfrom
         * mask data to config the specific.
         */
        if (pdata->direct_key_mask)
                keypad->direct_key_mask = pdata->direct_key_mask;
        else
                keypad->direct_key_mask = ((1 << direct_key_num) - 1) & ~mask;

        /* enable direct key */
        if (direct_key_num)
                kpc |= KPC_DE | KPC_DIE | KPC_DKN(direct_key_num);

        keypad_writel(KPC, kpc | KPC_RE_ZERO_DEB);
        keypad_writel(KPREC, DEFAULT_KPREC);
        keypad_writel(KPKDI, pdata->debounce_interval);
}

static int pxa27x_keypad_open(struct input_dev *dev)
{
        struct pxa27x_keypad *keypad = input_get_drvdata(dev);

        /* Enable unit clock */
        clk_prepare_enable(keypad->clk);
        pxa27x_keypad_config(keypad);

        return 0;
}

static void pxa27x_keypad_close(struct input_dev *dev)
{
        struct pxa27x_keypad *keypad = input_get_drvdata(dev);

        /* Disable clock unit */
        clk_disable_unprepare(keypad->clk);
}

#ifdef CONFIG_PM_SLEEP
static int pxa27x_keypad_suspend(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct pxa27x_keypad *keypad = platform_get_drvdata(pdev);

        /*
         * If the keypad is used a wake up source, clock can not be disabled.
         * Or it can not detect the key pressing.
         */
        if (device_may_wakeup(&pdev->dev))
                enable_irq_wake(keypad->irq);
        else
                clk_disable_unprepare(keypad->clk);

        return 0;
}

static int pxa27x_keypad_resume(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct pxa27x_keypad *keypad = platform_get_drvdata(pdev);
        struct input_dev *input_dev = keypad->input_dev;

        /*
         * If the keypad is used as wake up source, the clock is not turned
         * off. So do not need configure it again.
         */
        if (device_may_wakeup(&pdev->dev)) {
                disable_irq_wake(keypad->irq);
        } else {
                mutex_lock(&input_dev->mutex);

                if (input_dev->users) {
                        /* Enable unit clock */
                        clk_prepare_enable(keypad->clk);
                        pxa27x_keypad_config(keypad);
                }

                mutex_unlock(&input_dev->mutex);
        }

        return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(pxa27x_keypad_pm_ops,
                         pxa27x_keypad_suspend, pxa27x_keypad_resume);


static int pxa27x_keypad_probe(struct platform_device *pdev)
{
        const struct pxa27x_keypad_platform_data *pdata =
                                        dev_get_platdata(&pdev->dev);
        struct device_node *np = pdev->dev.of_node;
        struct pxa27x_keypad *keypad;
        struct input_dev *input_dev;
        struct resource *res;
        int irq, error;

        /* Driver need build keycode from device tree or pdata */
        if (!np && !pdata)
                return -EINVAL;

        irq = platform_get_irq(pdev, 0);
        if (irq < 0) {
                dev_err(&pdev->dev, "failed to get keypad irq\n");
                return -ENXIO;
        }

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (res == NULL) {
                dev_err(&pdev->dev, "failed to get I/O memory\n");
                return -ENXIO;
        }

        keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad),
                              GFP_KERNEL);
        if (!keypad)
                return -ENOMEM;

        input_dev = devm_input_allocate_device(&pdev->dev);
        if (!input_dev)
                return -ENOMEM;

        keypad->pdata = pdata;
        keypad->input_dev = input_dev;
        keypad->irq = irq;

        keypad->mmio_base = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(keypad->mmio_base))
                return PTR_ERR(keypad->mmio_base);

        keypad->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(keypad->clk)) {
                dev_err(&pdev->dev, "failed to get keypad clock\n");
                return PTR_ERR(keypad->clk);
        }

        input_dev->name = pdev->name;
        input_dev->id.bustype = BUS_HOST;
        input_dev->open = pxa27x_keypad_open;
        input_dev->close = pxa27x_keypad_close;
        input_dev->dev.parent = &pdev->dev;

        input_dev->keycode = keypad->keycodes;
        input_dev->keycodesize = sizeof(keypad->keycodes[0]);
        input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);

        input_set_drvdata(input_dev, keypad);

        input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
        input_set_capability(input_dev, EV_MSC, MSC_SCAN);

        if (pdata) {
                error = pxa27x_keypad_build_keycode(keypad);
        } else {
                error = pxa27x_keypad_build_keycode_from_dt(keypad);
                /*
                 * Data that we get from DT resides in dynamically
                 * allocated memory so we need to update our pdata
                 * pointer.
                 */
                pdata = keypad->pdata;
        }
        if (error) {
                dev_err(&pdev->dev, "failed to build keycode\n");
                return error;
        }

        keypad->row_shift = get_count_order(pdata->matrix_key_cols);

        if ((pdata->enable_rotary0 && keypad->rotary_rel_code[0] != -1) ||
            (pdata->enable_rotary1 && keypad->rotary_rel_code[1] != -1)) {
                input_dev->evbit[0] |= BIT_MASK(EV_REL);
        }

        error = devm_request_irq(&pdev->dev, irq, pxa27x_keypad_irq_handler,
                                 0, pdev->name, keypad);
        if (error) {
                dev_err(&pdev->dev, "failed to request IRQ\n");
                return error;
        }

        /* Register the input device */
        error = input_register_device(input_dev);
        if (error) {
                dev_err(&pdev->dev, "failed to register input device\n");
                return error;
        }

        platform_set_drvdata(pdev, keypad);
        device_init_wakeup(&pdev->dev, 1);

        return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id pxa27x_keypad_dt_match[] = {
        { .compatible = "marvell,pxa27x-keypad" },
        {},
};
MODULE_DEVICE_TABLE(of, pxa27x_keypad_dt_match);
#endif

static struct platform_driver pxa27x_keypad_driver = {
        .probe          = pxa27x_keypad_probe,
        .driver         = {
                .name   = "pxa27x-keypad",
                .of_match_table = of_match_ptr(pxa27x_keypad_dt_match),
                .pm     = &pxa27x_keypad_pm_ops,
        },
};
module_platform_driver(pxa27x_keypad_driver);

MODULE_DESCRIPTION("PXA27x Keypad Controller Driver");
MODULE_LICENSE("GPL");
/* work with hotplug and coldplug */
MODULE_ALIAS("platform:pxa27x-keypad");