omap-keypad.c

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/*
 * linux/drivers/input/keyboard/omap-keypad.c
 *
 * OMAP Keypad Driver
 *
 * Copyright (C) 2003 Nokia Corporation
 * Written by Timo Teräs <[email protected]>
 *
 * Added support for H2 & H3 Keypad
 * Copyright (C) 2004 Texas Instruments
 *
 * 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/types.h>
#include <linux/input.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/platform_data/gpio-omap.h>
#include <linux/platform_data/keypad-omap.h>

#undef NEW_BOARD_LEARNING_MODE

static void omap_kp_tasklet(unsigned long);
static void omap_kp_timer(unsigned long);

static unsigned char keypad_state[8];
static DEFINE_MUTEX(kp_enable_mutex);
static int kp_enable = 1;
static int kp_cur_group = -1;

struct omap_kp {
    struct input_dev *input;
    struct timer_list timer;
    int irq;
    unsigned int rows;
    unsigned int cols;
    unsigned long delay;
    unsigned int debounce;
    unsigned short keymap[];
};

static DECLARE_TASKLET_DISABLED(kp_tasklet, omap_kp_tasklet, 0);

static unsigned int *row_gpios;
static unsigned int *col_gpios;

#ifdef CONFIG_ARCH_OMAP2
static void set_col_gpio_val(struct omap_kp *omap_kp, u8 value)
{
    int col;

    for (col = 0; col < omap_kp->cols; col++)
        gpio_set_value(col_gpios[col], value & (1 << col));
}

static u8 get_row_gpio_val(struct omap_kp *omap_kp)
{
    int row;
    u8 value = 0;

    for (row = 0; row < omap_kp->rows; row++) {
        if (gpio_get_value(row_gpios[row]))
            value |= (1 << row);
    }
    return value;
}
#else
#define     set_col_gpio_val(x, y)  do {} while (0)
#define     get_row_gpio_val(x) 0
#endif

static irqreturn_t omap_kp_interrupt(int irq, void *dev_id)
{
    /* disable keyboard interrupt and schedule for handling */
    omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);

    tasklet_schedule(&kp_tasklet);

    return IRQ_HANDLED;
}

static void omap_kp_timer(unsigned long data)
{
    tasklet_schedule(&kp_tasklet);
}

static void omap_kp_scan_keypad(struct omap_kp *omap_kp, unsigned char *state)
{
    int col = 0;

    /* disable keyboard interrupt and schedule for handling */
    omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);

    /* read the keypad status */
    omap_writew(0xff, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
    for (col = 0; col < omap_kp->cols; col++) {
        omap_writew(~(1 << col) & 0xff,
                OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);

        udelay(omap_kp->delay);

        state[col] = ~omap_readw(OMAP1_MPUIO_BASE +
                     OMAP_MPUIO_KBR_LATCH) & 0xff;
    }
    omap_writew(0x00, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
    udelay(2);
}

static void omap_kp_tasklet(unsigned long data)
{
    struct omap_kp *omap_kp_data = (struct omap_kp *) data;
    unsigned short *keycodes = omap_kp_data->input->keycode;
    unsigned int row_shift = get_count_order(omap_kp_data->cols);
    unsigned char new_state[8], changed, key_down = 0;
    int col, row;
    int spurious = 0;

    /* check for any changes */
    omap_kp_scan_keypad(omap_kp_data, new_state);

    /* check for changes and print those */
    for (col = 0; col < omap_kp_data->cols; col++) {
        changed = new_state[col] ^ keypad_state[col];
        key_down |= new_state[col];
        if (changed == 0)
            continue;

        for (row = 0; row < omap_kp_data->rows; row++) {
            int key;
            if (!(changed & (1 << row)))
                continue;
#ifdef NEW_BOARD_LEARNING_MODE
            printk(KERN_INFO "omap-keypad: key %d-%d %s\n", col,
                   row, (new_state[col] & (1 << row)) ?
                   "pressed" : "released");
#else
            key = keycodes[MATRIX_SCAN_CODE(row, col, row_shift)];
            if (key < 0) {
                printk(KERN_WARNING
                      "omap-keypad: Spurious key event %d-%d\n",
                       col, row);
                /* We scan again after a couple of seconds */
                spurious = 1;
                continue;
            }

            if (!(kp_cur_group == (key & GROUP_MASK) ||
                  kp_cur_group == -1))
                continue;

            kp_cur_group = key & GROUP_MASK;
            input_report_key(omap_kp_data->input, key & ~GROUP_MASK,
                     new_state[col] & (1 << row));
#endif
        }
    }
    input_sync(omap_kp_data->input);
    memcpy(keypad_state, new_state, sizeof(keypad_state));

    if (key_down) {
        int delay = HZ / 20;
        /* some key is pressed - keep irq disabled and use timer
         * to poll the keypad */
        if (spurious)
            delay = 2 * HZ;
        mod_timer(&omap_kp_data->timer, jiffies + delay);
    } else {
        /* enable interrupts */
        omap_writew(0, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
        kp_cur_group = -1;
    }
}

static ssize_t omap_kp_enable_show(struct device *dev,
                   struct device_attribute *attr, char *buf)
{
    return sprintf(buf, "%u\n", kp_enable);
}

static ssize_t omap_kp_enable_store(struct device *dev, struct device_attribute *attr,
                    const char *buf, size_t count)
{
    struct omap_kp *omap_kp = dev_get_drvdata(dev);
    int state;

    if (sscanf(buf, "%u", &state) != 1)
        return -EINVAL;

    if ((state != 1) && (state != 0))
        return -EINVAL;

    mutex_lock(&kp_enable_mutex);
    if (state != kp_enable) {
        if (state)
            enable_irq(omap_kp->irq);
        else
            disable_irq(omap_kp->irq);
        kp_enable = state;
    }
    mutex_unlock(&kp_enable_mutex);

    return strnlen(buf, count);
}

static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, omap_kp_enable_show, omap_kp_enable_store);

#ifdef CONFIG_PM
static int omap_kp_suspend(struct platform_device *dev, pm_message_t state)
{
    /* Nothing yet */

    return 0;
}

static int omap_kp_resume(struct platform_device *dev)
{
    /* Nothing yet */

    return 0;
}
#else
#define omap_kp_suspend NULL
#define omap_kp_resume  NULL
#endif

static int __devinit omap_kp_probe(struct platform_device *pdev)
{
    struct omap_kp *omap_kp;
    struct input_dev *input_dev;
    struct omap_kp_platform_data *pdata =  pdev->dev.platform_data;
    int i, col_idx, row_idx, ret;
    unsigned int row_shift, keycodemax;

    if (!pdata->rows || !pdata->cols || !pdata->keymap_data) {
        printk(KERN_ERR "No rows, cols or keymap_data from pdata\n");
        return -EINVAL;
    }

    row_shift = get_count_order(pdata->cols);
    keycodemax = pdata->rows << row_shift;

    omap_kp = kzalloc(sizeof(struct omap_kp) +
            keycodemax * sizeof(unsigned short), GFP_KERNEL);
    input_dev = input_allocate_device();
    if (!omap_kp || !input_dev) {
        kfree(omap_kp);
        input_free_device(input_dev);
        return -ENOMEM;
    }

    platform_set_drvdata(pdev, omap_kp);

    omap_kp->input = input_dev;

    /* Disable the interrupt for the MPUIO keyboard */
    omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);

    if (pdata->delay)
        omap_kp->delay = pdata->delay;

    if (pdata->row_gpios && pdata->col_gpios) {
        row_gpios = pdata->row_gpios;
        col_gpios = pdata->col_gpios;
    }

    omap_kp->rows = pdata->rows;
    omap_kp->cols = pdata->cols;

    col_idx = 0;
    row_idx = 0;

    setup_timer(&omap_kp->timer, omap_kp_timer, (unsigned long)omap_kp);

    /* get the irq and init timer*/
    tasklet_enable(&kp_tasklet);
    kp_tasklet.data = (unsigned long) omap_kp;

    ret = device_create_file(&pdev->dev, &dev_attr_enable);
    if (ret < 0)
        goto err2;

    /* setup input device */
    input_dev->name = "omap-keypad";
    input_dev->phys = "omap-keypad/input0";
    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 = 0x0100;

    if (pdata->rep)
        __set_bit(EV_REP, input_dev->evbit);

    ret = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
                     pdata->rows, pdata->cols,
                     omap_kp->keymap, input_dev);
    if (ret < 0)
        goto err3;

    ret = input_register_device(omap_kp->input);
    if (ret < 0) {
        printk(KERN_ERR "Unable to register omap-keypad input device\n");
        goto err3;
    }

    if (pdata->dbounce)
        omap_writew(0xff, OMAP1_MPUIO_BASE + OMAP_MPUIO_GPIO_DEBOUNCING);

    /* scan current status and enable interrupt */
    omap_kp_scan_keypad(omap_kp, keypad_state);
    omap_kp->irq = platform_get_irq(pdev, 0);
    if (omap_kp->irq >= 0) {
        if (request_irq(omap_kp->irq, omap_kp_interrupt, 0,
                "omap-keypad", omap_kp) < 0)
            goto err4;
    }
    omap_writew(0, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);

    return 0;

err4:
    input_unregister_device(omap_kp->input);
    input_dev = NULL;
err3:
    device_remove_file(&pdev->dev, &dev_attr_enable);
err2:
    for (i = row_idx - 1; i >= 0; i--)
        gpio_free(row_gpios[i]);
    for (i = col_idx - 1; i >= 0; i--)
        gpio_free(col_gpios[i]);

    kfree(omap_kp);
    input_free_device(input_dev);

    return -EINVAL;
}

static int __devexit omap_kp_remove(struct platform_device *pdev)
{
    struct omap_kp *omap_kp = platform_get_drvdata(pdev);

    /* disable keypad interrupt handling */
    tasklet_disable(&kp_tasklet);
    omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
    free_irq(omap_kp->irq, omap_kp);

    del_timer_sync(&omap_kp->timer);
    tasklet_kill(&kp_tasklet);

    /* unregister everything */
    input_unregister_device(omap_kp->input);

    kfree(omap_kp);

    return 0;
}

static struct platform_driver omap_kp_driver = {
    .probe      = omap_kp_probe,
    .remove     = __devexit_p(omap_kp_remove),
    .suspend    = omap_kp_suspend,
    .resume     = omap_kp_resume,
    .driver     = {
        .name   = "omap-keypad",
        .owner  = THIS_MODULE,
    },
};
module_platform_driver(omap_kp_driver);

MODULE_AUTHOR("Timo Teräs");
MODULE_DESCRIPTION("OMAP Keypad Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:omap-keypad");