w90p910_keypad.c

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/*
 * Copyright (c) 2008-2009 Nuvoton technology corporation.
 *
 * Wan ZongShun <[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.
 *
 */

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

#include <linux/platform_data/keypad-w90p910.h>

/* Keypad Interface Control Registers */
#define KPI_CONF        0x00
#define KPI_3KCONF      0x04
#define KPI_LPCONF      0x08
#define KPI_STATUS      0x0C

#define IS1KEY          (0x01 << 16)
#define INTTR           (0x01 << 21)
#define KEY0R           (0x0f << 3)
#define KEY0C           0x07
#define DEBOUNCE_BIT        0x08
#define KSIZE0          (0x01 << 16)
#define KSIZE1          (0x01 << 17)
#define KPSEL           (0x01 << 19)
#define ENKP            (0x01 << 18)

#define KGET_RAW(n)     (((n) & KEY0R) >> 3)
#define KGET_COLUMN(n)      ((n) & KEY0C)

#define W90P910_NUM_ROWS    8
#define W90P910_NUM_COLS    8
#define W90P910_ROW_SHIFT   3

struct w90p910_keypad {
    const struct w90p910_keypad_platform_data *pdata;
    struct clk *clk;
    struct input_dev *input_dev;
    void __iomem *mmio_base;
    int irq;
    unsigned short keymap[W90P910_NUM_ROWS * W90P910_NUM_COLS];
};

static void w90p910_keypad_scan_matrix(struct w90p910_keypad *keypad,
                            unsigned int status)
{
    struct input_dev *input_dev = keypad->input_dev;
    unsigned int row = KGET_RAW(status);
    unsigned int col = KGET_COLUMN(status);
    unsigned int code = MATRIX_SCAN_CODE(row, col, W90P910_ROW_SHIFT);
    unsigned int key = keypad->keymap[code];

    input_event(input_dev, EV_MSC, MSC_SCAN, code);
    input_report_key(input_dev, key, 1);
    input_sync(input_dev);

    input_event(input_dev, EV_MSC, MSC_SCAN, code);
    input_report_key(input_dev, key, 0);
    input_sync(input_dev);
}

static irqreturn_t w90p910_keypad_irq_handler(int irq, void *dev_id)
{
    struct w90p910_keypad *keypad = dev_id;
    unsigned int  kstatus, val;

    kstatus = __raw_readl(keypad->mmio_base + KPI_STATUS);

    val = INTTR | IS1KEY;

    if (kstatus & val)
        w90p910_keypad_scan_matrix(keypad, kstatus);

    return IRQ_HANDLED;
}

static int w90p910_keypad_open(struct input_dev *dev)
{
    struct w90p910_keypad *keypad = input_get_drvdata(dev);
    const struct w90p910_keypad_platform_data *pdata = keypad->pdata;
    unsigned int val, config;

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

    val = __raw_readl(keypad->mmio_base + KPI_CONF);
    val |= (KPSEL | ENKP);
    val &= ~(KSIZE0 | KSIZE1);

    config = pdata->prescale | (pdata->debounce << DEBOUNCE_BIT);

    val |= config;

    __raw_writel(val, keypad->mmio_base + KPI_CONF);

    return 0;
}

static void w90p910_keypad_close(struct input_dev *dev)
{
    struct w90p910_keypad *keypad = input_get_drvdata(dev);

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

static int __devinit w90p910_keypad_probe(struct platform_device *pdev)
{
    const struct w90p910_keypad_platform_data *pdata =
                        pdev->dev.platform_data;
    const struct matrix_keymap_data *keymap_data;
    struct w90p910_keypad *keypad;
    struct input_dev *input_dev;
    struct resource *res;
    int irq;
    int error;

    if (!pdata) {
        dev_err(&pdev->dev, "no platform data defined\n");
        return -EINVAL;
    }

    keymap_data = pdata->keymap_data;

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

    keypad = kzalloc(sizeof(struct w90p910_keypad), GFP_KERNEL);
    input_dev = input_allocate_device();
    if (!keypad || !input_dev) {
        dev_err(&pdev->dev, "failed to allocate driver data\n");
        error = -ENOMEM;
        goto failed_free;
    }

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

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

    res = request_mem_region(res->start, resource_size(res), pdev->name);
    if (res == NULL) {
        dev_err(&pdev->dev, "failed to request I/O memory\n");
        error = -EBUSY;
        goto failed_free;
    }

    keypad->mmio_base = ioremap(res->start, resource_size(res));
    if (keypad->mmio_base == NULL) {
        dev_err(&pdev->dev, "failed to remap I/O memory\n");
        error = -ENXIO;
        goto failed_free_res;
    }

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

    /* set multi-function pin for w90p910 kpi. */
    mfp_set_groupi(&pdev->dev);

    input_dev->name = pdev->name;
    input_dev->id.bustype = BUS_HOST;
    input_dev->open = w90p910_keypad_open;
    input_dev->close = w90p910_keypad_close;
    input_dev->dev.parent = &pdev->dev;

    error = matrix_keypad_build_keymap(keymap_data, NULL,
                       W90P910_NUM_ROWS, W90P910_NUM_COLS,
                       keypad->keymap, input_dev);
    if (error) {
        dev_err(&pdev->dev, "failed to build keymap\n");
        goto failed_put_clk;
    }

    error = request_irq(keypad->irq, w90p910_keypad_irq_handler,
                0, pdev->name, keypad);
    if (error) {
        dev_err(&pdev->dev, "failed to request IRQ\n");
        goto failed_put_clk;
    }

    __set_bit(EV_REP, input_dev->evbit);
    input_set_capability(input_dev, EV_MSC, MSC_SCAN);
    input_set_drvdata(input_dev, keypad);

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

    platform_set_drvdata(pdev, keypad);
    return 0;

failed_free_irq:
    free_irq(irq, pdev);
failed_put_clk:
    clk_put(keypad->clk);
failed_free_io:
    iounmap(keypad->mmio_base);
failed_free_res:
    release_mem_region(res->start, resource_size(res));
failed_free:
    input_free_device(input_dev);
    kfree(keypad);
    return error;
}

static int __devexit w90p910_keypad_remove(struct platform_device *pdev)
{
    struct w90p910_keypad *keypad = platform_get_drvdata(pdev);
    struct resource *res;

    free_irq(keypad->irq, pdev);

    clk_put(keypad->clk);

    input_unregister_device(keypad->input_dev);

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

    platform_set_drvdata(pdev, NULL);
    kfree(keypad);

    return 0;
}

static struct platform_driver w90p910_keypad_driver = {
    .probe      = w90p910_keypad_probe,
    .remove     = __devexit_p(w90p910_keypad_remove),
    .driver     = {
        .name   = "nuc900-kpi",
        .owner  = THIS_MODULE,
    },
};
module_platform_driver(w90p910_keypad_driver);

MODULE_AUTHOR("Wan ZongShun <[email protected]>");
MODULE_DESCRIPTION("w90p910 keypad driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:nuc900-keypad");