bf54x-keys.c

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/*
 * File:         drivers/input/keyboard/bf54x-keys.c
 * Based on:
 * Author:       Michael Hennerich <[email protected]>
 *
 * Created:
 * Description:  keypad driver for Analog Devices Blackfin BF54x Processors
 *
 *
 * Modified:
 *               Copyright 2007-2008 Analog Devices Inc.
 *
 * Bugs:         Enter bugs at http://blackfin.uclinux.org/
 *
 * 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, see the file COPYING, or write
 * to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <linux/module.h>

#include <linux/init.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/pm.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/input.h>

#include <asm/portmux.h>
#include <mach/bf54x_keys.h>

#define DRV_NAME    "bf54x-keys"
#define TIME_SCALE  100 /* 100 ns */
#define MAX_MULT    (0xFF * TIME_SCALE)
#define MAX_RC      8   /* Max Row/Col */

static const u16 per_rows[] = {
    P_KEY_ROW7,
    P_KEY_ROW6,
    P_KEY_ROW5,
    P_KEY_ROW4,
    P_KEY_ROW3,
    P_KEY_ROW2,
    P_KEY_ROW1,
    P_KEY_ROW0,
    0
};

static const u16 per_cols[] = {
    P_KEY_COL7,
    P_KEY_COL6,
    P_KEY_COL5,
    P_KEY_COL4,
    P_KEY_COL3,
    P_KEY_COL2,
    P_KEY_COL1,
    P_KEY_COL0,
    0
};

struct bf54x_kpad {
    struct input_dev *input;
    int irq;
    unsigned short lastkey;
    unsigned short *keycode;
    struct timer_list timer;
    unsigned int keyup_test_jiffies;
    unsigned short kpad_msel;
    unsigned short kpad_prescale;
    unsigned short kpad_ctl;
};

static inline int bfin_kpad_find_key(struct bf54x_kpad *bf54x_kpad,
            struct input_dev *input, u16 keyident)
{
    u16 i;

    for (i = 0; i < input->keycodemax; i++)
        if (bf54x_kpad->keycode[i + input->keycodemax] == keyident)
            return bf54x_kpad->keycode[i];
    return -1;
}

static inline void bfin_keycodecpy(unsigned short *keycode,
            const unsigned int *pdata_kc,
            unsigned short keymapsize)
{
    unsigned int i;

    for (i = 0; i < keymapsize; i++) {
        keycode[i] = pdata_kc[i] & 0xffff;
        keycode[i + keymapsize] = pdata_kc[i] >> 16;
    }
}

static inline u16 bfin_kpad_get_prescale(u32 timescale)
{
    u32 sclk = get_sclk();

    return ((((sclk / 1000) * timescale) / 1024) - 1);
}

static inline u16 bfin_kpad_get_keypressed(struct bf54x_kpad *bf54x_kpad)
{
    return (bfin_read_KPAD_STAT() & KPAD_PRESSED);
}

static inline void bfin_kpad_clear_irq(void)
{
    bfin_write_KPAD_STAT(0xFFFF);
    bfin_write_KPAD_ROWCOL(0xFFFF);
}

static void bfin_kpad_timer(unsigned long data)
{
    struct platform_device *pdev =  (struct platform_device *) data;
    struct bf54x_kpad *bf54x_kpad = platform_get_drvdata(pdev);

    if (bfin_kpad_get_keypressed(bf54x_kpad)) {
        /* Try again later */
        mod_timer(&bf54x_kpad->timer,
              jiffies + bf54x_kpad->keyup_test_jiffies);
        return;
    }

    input_report_key(bf54x_kpad->input, bf54x_kpad->lastkey, 0);
    input_sync(bf54x_kpad->input);

    /* Clear IRQ Status */

    bfin_kpad_clear_irq();
    enable_irq(bf54x_kpad->irq);
}

static irqreturn_t bfin_kpad_isr(int irq, void *dev_id)
{
    struct platform_device *pdev = dev_id;
    struct bf54x_kpad *bf54x_kpad = platform_get_drvdata(pdev);
    struct input_dev *input = bf54x_kpad->input;
    int key;
    u16 rowcol = bfin_read_KPAD_ROWCOL();

    key = bfin_kpad_find_key(bf54x_kpad, input, rowcol);

    input_report_key(input, key, 1);
    input_sync(input);

    if (bfin_kpad_get_keypressed(bf54x_kpad)) {
        disable_irq_nosync(bf54x_kpad->irq);
        bf54x_kpad->lastkey = key;
        mod_timer(&bf54x_kpad->timer,
              jiffies + bf54x_kpad->keyup_test_jiffies);
    } else {
        input_report_key(input, key, 0);
        input_sync(input);

        bfin_kpad_clear_irq();
    }

    return IRQ_HANDLED;
}

static int __devinit bfin_kpad_probe(struct platform_device *pdev)
{
    struct bf54x_kpad *bf54x_kpad;
    struct bfin_kpad_platform_data *pdata = pdev->dev.platform_data;
    struct input_dev *input;
    int i, error;

    if (!pdata->rows || !pdata->cols || !pdata->keymap) {
        dev_err(&pdev->dev, "no rows, cols or keymap from pdata\n");
        return -EINVAL;
    }

    if (!pdata->keymapsize ||
        pdata->keymapsize > (pdata->rows * pdata->cols)) {
        dev_err(&pdev->dev, "invalid keymapsize\n");
        return -EINVAL;
    }

    bf54x_kpad = kzalloc(sizeof(struct bf54x_kpad), GFP_KERNEL);
    if (!bf54x_kpad)
        return -ENOMEM;

    platform_set_drvdata(pdev, bf54x_kpad);

    /* Allocate memory for keymap followed by private LUT */
    bf54x_kpad->keycode = kmalloc(pdata->keymapsize *
                    sizeof(unsigned short) * 2, GFP_KERNEL);
    if (!bf54x_kpad->keycode) {
        error = -ENOMEM;
        goto out;
    }

    if (!pdata->debounce_time || pdata->debounce_time > MAX_MULT ||
        !pdata->coldrive_time || pdata->coldrive_time > MAX_MULT) {
        dev_warn(&pdev->dev,
            "invalid platform debounce/columndrive time\n");
        bfin_write_KPAD_MSEL(0xFF0);    /* Default MSEL */
    } else {
        bfin_write_KPAD_MSEL(
            ((pdata->debounce_time / TIME_SCALE)
                        & DBON_SCALE) |
            (((pdata->coldrive_time / TIME_SCALE) << 8)
                        & COLDRV_SCALE));

    }

    if (!pdata->keyup_test_interval)
        bf54x_kpad->keyup_test_jiffies = msecs_to_jiffies(50);
    else
        bf54x_kpad->keyup_test_jiffies =
            msecs_to_jiffies(pdata->keyup_test_interval);

    if (peripheral_request_list((u16 *)&per_rows[MAX_RC - pdata->rows],
                    DRV_NAME)) {
        dev_err(&pdev->dev, "requesting peripherals failed\n");
        error = -EFAULT;
        goto out0;
    }

    if (peripheral_request_list((u16 *)&per_cols[MAX_RC - pdata->cols],
                    DRV_NAME)) {
        dev_err(&pdev->dev, "requesting peripherals failed\n");
        error = -EFAULT;
        goto out1;
    }

    bf54x_kpad->irq = platform_get_irq(pdev, 0);
    if (bf54x_kpad->irq < 0) {
        error = -ENODEV;
        goto out2;
    }

    error = request_irq(bf54x_kpad->irq, bfin_kpad_isr,
                0, DRV_NAME, pdev);
    if (error) {
        dev_err(&pdev->dev, "unable to claim irq %d\n",
            bf54x_kpad->irq);
        goto out2;
    }

    input = input_allocate_device();
    if (!input) {
        error = -ENOMEM;
        goto out3;
    }

    bf54x_kpad->input = input;

    input->name = pdev->name;
    input->phys = "bf54x-keys/input0";
    input->dev.parent = &pdev->dev;

    input_set_drvdata(input, bf54x_kpad);

    input->id.bustype = BUS_HOST;
    input->id.vendor = 0x0001;
    input->id.product = 0x0001;
    input->id.version = 0x0100;

    input->keycodesize = sizeof(unsigned short);
    input->keycodemax = pdata->keymapsize;
    input->keycode = bf54x_kpad->keycode;

    bfin_keycodecpy(bf54x_kpad->keycode, pdata->keymap, pdata->keymapsize);

    /* setup input device */
    __set_bit(EV_KEY, input->evbit);

    if (pdata->repeat)
        __set_bit(EV_REP, input->evbit);

    for (i = 0; i < input->keycodemax; i++)
        __set_bit(bf54x_kpad->keycode[i] & KEY_MAX, input->keybit);
    __clear_bit(KEY_RESERVED, input->keybit);

    error = input_register_device(input);
    if (error) {
        dev_err(&pdev->dev, "unable to register input device\n");
        goto out4;
    }

    /* Init Keypad Key Up/Release test timer */

    setup_timer(&bf54x_kpad->timer, bfin_kpad_timer, (unsigned long) pdev);

    bfin_write_KPAD_PRESCALE(bfin_kpad_get_prescale(TIME_SCALE));

    bfin_write_KPAD_CTL((((pdata->cols - 1) << 13) & KPAD_COLEN) |
                (((pdata->rows - 1) << 10) & KPAD_ROWEN) |
                (2 & KPAD_IRQMODE));

    bfin_write_KPAD_CTL(bfin_read_KPAD_CTL() | KPAD_EN);

    device_init_wakeup(&pdev->dev, 1);

    return 0;

out4:
    input_free_device(input);
out3:
    free_irq(bf54x_kpad->irq, pdev);
out2:
    peripheral_free_list((u16 *)&per_cols[MAX_RC - pdata->cols]);
out1:
    peripheral_free_list((u16 *)&per_rows[MAX_RC - pdata->rows]);
out0:
    kfree(bf54x_kpad->keycode);
out:
    kfree(bf54x_kpad);
    platform_set_drvdata(pdev, NULL);

    return error;
}

static int __devexit bfin_kpad_remove(struct platform_device *pdev)
{
    struct bfin_kpad_platform_data *pdata = pdev->dev.platform_data;
    struct bf54x_kpad *bf54x_kpad = platform_get_drvdata(pdev);

    del_timer_sync(&bf54x_kpad->timer);
    free_irq(bf54x_kpad->irq, pdev);

    input_unregister_device(bf54x_kpad->input);

    peripheral_free_list((u16 *)&per_rows[MAX_RC - pdata->rows]);
    peripheral_free_list((u16 *)&per_cols[MAX_RC - pdata->cols]);

    kfree(bf54x_kpad->keycode);
    kfree(bf54x_kpad);
    platform_set_drvdata(pdev, NULL);

    return 0;
}

#ifdef CONFIG_PM
static int bfin_kpad_suspend(struct platform_device *pdev, pm_message_t state)
{
    struct bf54x_kpad *bf54x_kpad = platform_get_drvdata(pdev);

    bf54x_kpad->kpad_msel = bfin_read_KPAD_MSEL();
    bf54x_kpad->kpad_prescale = bfin_read_KPAD_PRESCALE();
    bf54x_kpad->kpad_ctl = bfin_read_KPAD_CTL();

    if (device_may_wakeup(&pdev->dev))
        enable_irq_wake(bf54x_kpad->irq);

    return 0;
}

static int bfin_kpad_resume(struct platform_device *pdev)
{
    struct bf54x_kpad *bf54x_kpad = platform_get_drvdata(pdev);

    bfin_write_KPAD_MSEL(bf54x_kpad->kpad_msel);
    bfin_write_KPAD_PRESCALE(bf54x_kpad->kpad_prescale);
    bfin_write_KPAD_CTL(bf54x_kpad->kpad_ctl);

    if (device_may_wakeup(&pdev->dev))
        disable_irq_wake(bf54x_kpad->irq);

    return 0;
}
#else
# define bfin_kpad_suspend NULL
# define bfin_kpad_resume  NULL
#endif

static struct platform_driver bfin_kpad_device_driver = {
    .driver     = {
        .name   = DRV_NAME,
        .owner  = THIS_MODULE,
    },
    .probe      = bfin_kpad_probe,
    .remove     = __devexit_p(bfin_kpad_remove),
    .suspend    = bfin_kpad_suspend,
    .resume     = bfin_kpad_resume,
};
module_platform_driver(bfin_kpad_device_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michael Hennerich <[email protected]>");
MODULE_DESCRIPTION("Keypad driver for BF54x Processors");
MODULE_ALIAS("platform:bf54x-keys");