omap4-keypad.c

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/*
 * OMAP4 Keypad Driver
 *
 * Copyright (C) 2010 Texas Instruments
 *
 * Author: Abraham Arce <[email protected]>
 * Initial Code: Syed Rafiuddin <[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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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/init.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/errno.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>

#include <linux/platform_data/omap4-keypad.h>

/* OMAP4 registers */
#define OMAP4_KBD_REVISION      0x00
#define OMAP4_KBD_SYSCONFIG     0x10
#define OMAP4_KBD_SYSSTATUS     0x14
#define OMAP4_KBD_IRQSTATUS     0x18
#define OMAP4_KBD_IRQENABLE     0x1C
#define OMAP4_KBD_WAKEUPENABLE      0x20
#define OMAP4_KBD_PENDING       0x24
#define OMAP4_KBD_CTRL          0x28
#define OMAP4_KBD_DEBOUNCINGTIME    0x2C
#define OMAP4_KBD_LONGKEYTIME       0x30
#define OMAP4_KBD_TIMEOUT       0x34
#define OMAP4_KBD_STATEMACHINE      0x38
#define OMAP4_KBD_ROWINPUTS     0x3C
#define OMAP4_KBD_COLUMNOUTPUTS     0x40
#define OMAP4_KBD_FULLCODE31_0      0x44
#define OMAP4_KBD_FULLCODE63_32     0x48

/* OMAP4 bit definitions */
#define OMAP4_DEF_IRQENABLE_EVENTEN (1 << 0)
#define OMAP4_DEF_IRQENABLE_LONGKEY (1 << 1)
#define OMAP4_DEF_IRQENABLE_TIMEOUTEN   (1 << 2)
#define OMAP4_DEF_WUP_EVENT_ENA     (1 << 0)
#define OMAP4_DEF_WUP_LONG_KEY_ENA  (1 << 1)
#define OMAP4_DEF_CTRL_NOSOFTMODE   (1 << 1)
#define OMAP4_DEF_CTRLPTVVALUE      (1 << 2)
#define OMAP4_DEF_CTRLPTV       (1 << 1)

/* OMAP4 values */
#define OMAP4_VAL_IRQDISABLE        0x00
#define OMAP4_VAL_DEBOUNCINGTIME    0x07
#define OMAP4_VAL_FUNCTIONALCFG     0x1E

#define OMAP4_MASK_IRQSTATUSDISABLE 0xFFFF

enum {
    KBD_REVISION_OMAP4 = 0,
    KBD_REVISION_OMAP5,
};

struct omap4_keypad {
    struct input_dev *input;

    void __iomem *base;
    unsigned int irq;

    unsigned int rows;
    unsigned int cols;
    u32 reg_offset;
    u32 irqreg_offset;
    unsigned int row_shift;
    bool no_autorepeat;
    unsigned char key_state[8];
    unsigned short *keymap;
};

static int kbd_readl(struct omap4_keypad *keypad_data, u32 offset)
{
    return __raw_readl(keypad_data->base +
                keypad_data->reg_offset + offset);
}

static void kbd_writel(struct omap4_keypad *keypad_data, u32 offset, u32 value)
{
    __raw_writel(value,
             keypad_data->base + keypad_data->reg_offset + offset);
}

static int kbd_read_irqreg(struct omap4_keypad *keypad_data, u32 offset)
{
    return __raw_readl(keypad_data->base +
                keypad_data->irqreg_offset + offset);
}

static void kbd_write_irqreg(struct omap4_keypad *keypad_data,
                 u32 offset, u32 value)
{
    __raw_writel(value,
             keypad_data->base + keypad_data->irqreg_offset + offset);
}


/* Interrupt handler */
static irqreturn_t omap4_keypad_interrupt(int irq, void *dev_id)
{
    struct omap4_keypad *keypad_data = dev_id;
    struct input_dev *input_dev = keypad_data->input;
    unsigned char key_state[ARRAY_SIZE(keypad_data->key_state)];
    unsigned int col, row, code, changed;
    u32 *new_state = (u32 *) key_state;

    /* Disable interrupts */
    kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
             OMAP4_VAL_IRQDISABLE);

    *new_state = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0);
    *(new_state + 1) = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32);

    for (row = 0; row < keypad_data->rows; row++) {
        changed = key_state[row] ^ keypad_data->key_state[row];
        if (!changed)
            continue;

        for (col = 0; col < keypad_data->cols; col++) {
            if (changed & (1 << col)) {
                code = MATRIX_SCAN_CODE(row, col,
                        keypad_data->row_shift);
                input_event(input_dev, EV_MSC, MSC_SCAN, code);
                input_report_key(input_dev,
                         keypad_data->keymap[code],
                         key_state[row] & (1 << col));
            }
        }
    }

    input_sync(input_dev);

    memcpy(keypad_data->key_state, key_state,
        sizeof(keypad_data->key_state));

    /* clear pending interrupts */
    kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
             kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));

    /* enable interrupts */
    kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
        OMAP4_DEF_IRQENABLE_EVENTEN |
                OMAP4_DEF_IRQENABLE_LONGKEY);

    return IRQ_HANDLED;
}

static int omap4_keypad_open(struct input_dev *input)
{
    struct omap4_keypad *keypad_data = input_get_drvdata(input);

    pm_runtime_get_sync(input->dev.parent);

    disable_irq(keypad_data->irq);

    kbd_writel(keypad_data, OMAP4_KBD_CTRL,
            OMAP4_VAL_FUNCTIONALCFG);
    kbd_writel(keypad_data, OMAP4_KBD_DEBOUNCINGTIME,
            OMAP4_VAL_DEBOUNCINGTIME);
    kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
            OMAP4_VAL_IRQDISABLE);
    kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
            OMAP4_DEF_IRQENABLE_EVENTEN |
                OMAP4_DEF_IRQENABLE_LONGKEY);
    kbd_writel(keypad_data, OMAP4_KBD_WAKEUPENABLE,
            OMAP4_DEF_WUP_EVENT_ENA | OMAP4_DEF_WUP_LONG_KEY_ENA);

    enable_irq(keypad_data->irq);

    return 0;
}

static void omap4_keypad_close(struct input_dev *input)
{
    struct omap4_keypad *keypad_data = input_get_drvdata(input);

    disable_irq(keypad_data->irq);

    /* Disable interrupts */
    kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
             OMAP4_VAL_IRQDISABLE);

    /* clear pending interrupts */
    kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
             kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));

    enable_irq(keypad_data->irq);

    pm_runtime_put_sync(input->dev.parent);
}

#ifdef CONFIG_OF
static int __devinit omap4_keypad_parse_dt(struct device *dev,
                       struct omap4_keypad *keypad_data)
{
    struct device_node *np = dev->of_node;

    if (!np) {
        dev_err(dev, "missing DT data");
        return -EINVAL;
    }

    of_property_read_u32(np, "keypad,num-rows", &keypad_data->rows);
    of_property_read_u32(np, "keypad,num-columns", &keypad_data->cols);
    if (!keypad_data->rows || !keypad_data->cols) {
        dev_err(dev, "number of keypad rows/columns not specified\n");
        return -EINVAL;
    }

    if (of_get_property(np, "linux,input-no-autorepeat", NULL))
        keypad_data->no_autorepeat = true;

    return 0;
}
#else
static inline int omap4_keypad_parse_dt(struct device *dev,
                    struct omap4_keypad *keypad_data)
{
    return -ENOSYS;
}
#endif

static int __devinit omap4_keypad_probe(struct platform_device *pdev)
{
    const struct omap4_keypad_platform_data *pdata =
                dev_get_platdata(&pdev->dev);
    const struct matrix_keymap_data *keymap_data =
                pdata ? pdata->keymap_data : NULL;
    struct omap4_keypad *keypad_data;
    struct input_dev *input_dev;
    struct resource *res;
    unsigned int max_keys;
    int rev;
    int irq;
    int error;

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!res) {
        dev_err(&pdev->dev, "no base address specified\n");
        return -EINVAL;
    }

    irq = platform_get_irq(pdev, 0);
    if (!irq) {
        dev_err(&pdev->dev, "no keyboard irq assigned\n");
        return -EINVAL;
    }

    keypad_data = kzalloc(sizeof(struct omap4_keypad), GFP_KERNEL);
    if (!keypad_data) {
        dev_err(&pdev->dev, "keypad_data memory allocation failed\n");
        return -ENOMEM;
    }

    keypad_data->irq = irq;

    if (pdata) {
        keypad_data->rows = pdata->rows;
        keypad_data->cols = pdata->cols;
    } else {
        error = omap4_keypad_parse_dt(&pdev->dev, keypad_data);
        if (error)
            return error;
    }

    res = request_mem_region(res->start, resource_size(res), pdev->name);
    if (!res) {
        dev_err(&pdev->dev, "can't request mem region\n");
        error = -EBUSY;
        goto err_free_keypad;
    }

    keypad_data->base = ioremap(res->start, resource_size(res));
    if (!keypad_data->base) {
        dev_err(&pdev->dev, "can't ioremap mem resource\n");
        error = -ENOMEM;
        goto err_release_mem;
    }


    /*
     * Enable clocks for the keypad module so that we can read
     * revision register.
     */
    pm_runtime_enable(&pdev->dev);
    error = pm_runtime_get_sync(&pdev->dev);
    if (error) {
        dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
        goto err_unmap;
    }
    rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
    rev &= 0x03 << 30;
    rev >>= 30;
    switch (rev) {
    case KBD_REVISION_OMAP4:
        keypad_data->reg_offset = 0x00;
        keypad_data->irqreg_offset = 0x00;
        break;
    case KBD_REVISION_OMAP5:
        keypad_data->reg_offset = 0x10;
        keypad_data->irqreg_offset = 0x0c;
        break;
    default:
        dev_err(&pdev->dev,
            "Keypad reports unsupported revision %d", rev);
        error = -EINVAL;
        goto err_pm_put_sync;
    }

    /* input device allocation */
    keypad_data->input = input_dev = input_allocate_device();
    if (!input_dev) {
        error = -ENOMEM;
        goto err_pm_put_sync;
    }

    input_dev->name = pdev->name;
    input_dev->dev.parent = &pdev->dev;
    input_dev->id.bustype = BUS_HOST;
    input_dev->id.vendor = 0x0001;
    input_dev->id.product = 0x0001;
    input_dev->id.version = 0x0001;

    input_dev->open = omap4_keypad_open;
    input_dev->close = omap4_keypad_close;

    input_set_capability(input_dev, EV_MSC, MSC_SCAN);
    if (!keypad_data->no_autorepeat)
        __set_bit(EV_REP, input_dev->evbit);

    input_set_drvdata(input_dev, keypad_data);

    keypad_data->row_shift = get_count_order(keypad_data->cols);
    max_keys = keypad_data->rows << keypad_data->row_shift;
    keypad_data->keymap = kzalloc(max_keys * sizeof(keypad_data->keymap[0]),
                      GFP_KERNEL);
    if (!keypad_data->keymap) {
        dev_err(&pdev->dev, "Not enough memory for keymap\n");
        error = -ENOMEM;
        goto err_free_input;
    }

    error = matrix_keypad_build_keymap(keymap_data, NULL,
                       keypad_data->rows, keypad_data->cols,
                       keypad_data->keymap, input_dev);
    if (error) {
        dev_err(&pdev->dev, "failed to build keymap\n");
        goto err_free_keymap;
    }

    error = request_irq(keypad_data->irq, omap4_keypad_interrupt,
                 IRQF_TRIGGER_RISING,
                 "omap4-keypad", keypad_data);
    if (error) {
        dev_err(&pdev->dev, "failed to register interrupt\n");
        goto err_free_input;
    }

    pm_runtime_put_sync(&pdev->dev);

    error = input_register_device(keypad_data->input);
    if (error < 0) {
        dev_err(&pdev->dev, "failed to register input device\n");
        goto err_pm_disable;
    }

    platform_set_drvdata(pdev, keypad_data);
    return 0;

err_pm_disable:
    pm_runtime_disable(&pdev->dev);
    free_irq(keypad_data->irq, keypad_data);
err_free_keymap:
    kfree(keypad_data->keymap);
err_free_input:
    input_free_device(input_dev);
err_pm_put_sync:
    pm_runtime_put_sync(&pdev->dev);
err_unmap:
    iounmap(keypad_data->base);
err_release_mem:
    release_mem_region(res->start, resource_size(res));
err_free_keypad:
    kfree(keypad_data);
    return error;
}

static int __devexit omap4_keypad_remove(struct platform_device *pdev)
{
    struct omap4_keypad *keypad_data = platform_get_drvdata(pdev);
    struct resource *res;

    free_irq(keypad_data->irq, keypad_data);

    pm_runtime_disable(&pdev->dev);

    input_unregister_device(keypad_data->input);

    iounmap(keypad_data->base);

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    release_mem_region(res->start, resource_size(res));

    kfree(keypad_data->keymap);
    kfree(keypad_data);

    platform_set_drvdata(pdev, NULL);

    return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id omap_keypad_dt_match[] = {
    { .compatible = "ti,omap4-keypad" },
    {},
};
MODULE_DEVICE_TABLE(of, omap_keypad_dt_match);
#endif

static struct platform_driver omap4_keypad_driver = {
    .probe      = omap4_keypad_probe,
    .remove     = __devexit_p(omap4_keypad_remove),
    .driver     = {
        .name   = "omap4-keypad",
        .owner  = THIS_MODULE,
        .of_match_table = of_match_ptr(omap_keypad_dt_match),
    },
};
module_platform_driver(omap4_keypad_driver);

MODULE_AUTHOR("Texas Instruments");
MODULE_DESCRIPTION("OMAP4 Keypad Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:omap4-keypad");