pm8xxx-vibrator.c

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/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/mfd/pm8xxx/core.h>

#define VIB_DRV         0x4A

#define VIB_DRV_SEL_MASK    0xf8
#define VIB_DRV_SEL_SHIFT   0x03
#define VIB_DRV_EN_MANUAL_MASK  0xfc

#define VIB_MAX_LEVEL_mV    (3100)
#define VIB_MIN_LEVEL_mV    (1200)
#define VIB_MAX_LEVELS      (VIB_MAX_LEVEL_mV - VIB_MIN_LEVEL_mV)

#define MAX_FF_SPEED        0xff

struct pm8xxx_vib {
    struct input_dev *vib_input_dev;
    struct work_struct work;
    struct device *dev;
    int speed;
    int level;
    bool active;
    u8  reg_vib_drv;
};

static int pm8xxx_vib_read_u8(struct pm8xxx_vib *vib,
                 u8 *data, u16 reg)
{
    int rc;

    rc = pm8xxx_readb(vib->dev->parent, reg, data);
    if (rc < 0)
        dev_warn(vib->dev, "Error reading pm8xxx reg 0x%x(0x%x)\n",
                reg, rc);
    return rc;
}

static int pm8xxx_vib_write_u8(struct pm8xxx_vib *vib,
                 u8 data, u16 reg)
{
    int rc;

    rc = pm8xxx_writeb(vib->dev->parent, reg, data);
    if (rc < 0)
        dev_warn(vib->dev, "Error writing pm8xxx reg 0x%x(0x%x)\n",
                reg, rc);
    return rc;
}

static int pm8xxx_vib_set(struct pm8xxx_vib *vib, bool on)
{
    int rc;
    u8 val = vib->reg_vib_drv;

    if (on)
        val |= ((vib->level << VIB_DRV_SEL_SHIFT) & VIB_DRV_SEL_MASK);
    else
        val &= ~VIB_DRV_SEL_MASK;

    rc = pm8xxx_vib_write_u8(vib, val, VIB_DRV);
    if (rc < 0)
        return rc;

    vib->reg_vib_drv = val;
    return 0;
}

static void pm8xxx_work_handler(struct work_struct *work)
{
    struct pm8xxx_vib *vib = container_of(work, struct pm8xxx_vib, work);
    int rc;
    u8 val;

    rc = pm8xxx_vib_read_u8(vib, &val, VIB_DRV);
    if (rc < 0)
        return;

    /*
     * pmic vibrator supports voltage ranges from 1.2 to 3.1V, so
     * scale the level to fit into these ranges.
     */
    if (vib->speed) {
        vib->active = true;
        vib->level = ((VIB_MAX_LEVELS * vib->speed) / MAX_FF_SPEED) +
                        VIB_MIN_LEVEL_mV;
        vib->level /= 100;
    } else {
        vib->active = false;
        vib->level = VIB_MIN_LEVEL_mV / 100;
    }

    pm8xxx_vib_set(vib, vib->active);
}

static void pm8xxx_vib_close(struct input_dev *dev)
{
    struct pm8xxx_vib *vib = input_get_drvdata(dev);

    cancel_work_sync(&vib->work);
    if (vib->active)
        pm8xxx_vib_set(vib, false);
}

static int pm8xxx_vib_play_effect(struct input_dev *dev, void *data,
                  struct ff_effect *effect)
{
    struct pm8xxx_vib *vib = input_get_drvdata(dev);

    vib->speed = effect->u.rumble.strong_magnitude >> 8;
    if (!vib->speed)
        vib->speed = effect->u.rumble.weak_magnitude >> 9;

    schedule_work(&vib->work);

    return 0;
}

static int __devinit pm8xxx_vib_probe(struct platform_device *pdev)

{
    struct pm8xxx_vib *vib;
    struct input_dev *input_dev;
    int error;
    u8 val;

    vib = kzalloc(sizeof(*vib), GFP_KERNEL);
    input_dev = input_allocate_device();
    if (!vib || !input_dev) {
        dev_err(&pdev->dev, "couldn't allocate memory\n");
        error = -ENOMEM;
        goto err_free_mem;
    }

    INIT_WORK(&vib->work, pm8xxx_work_handler);
    vib->dev = &pdev->dev;
    vib->vib_input_dev = input_dev;

    /* operate in manual mode */
    error = pm8xxx_vib_read_u8(vib, &val, VIB_DRV);
    if (error < 0)
        goto err_free_mem;
    val &= ~VIB_DRV_EN_MANUAL_MASK;
    error = pm8xxx_vib_write_u8(vib, val, VIB_DRV);
    if (error < 0)
        goto err_free_mem;

    vib->reg_vib_drv = val;

    input_dev->name = "pm8xxx_vib_ffmemless";
    input_dev->id.version = 1;
    input_dev->dev.parent = &pdev->dev;
    input_dev->close = pm8xxx_vib_close;
    input_set_drvdata(input_dev, vib);
    input_set_capability(vib->vib_input_dev, EV_FF, FF_RUMBLE);

    error = input_ff_create_memless(input_dev, NULL,
                    pm8xxx_vib_play_effect);
    if (error) {
        dev_err(&pdev->dev,
            "couldn't register vibrator as FF device\n");
        goto err_free_mem;
    }

    error = input_register_device(input_dev);
    if (error) {
        dev_err(&pdev->dev, "couldn't register input device\n");
        goto err_destroy_memless;
    }

    platform_set_drvdata(pdev, vib);
    return 0;

err_destroy_memless:
    input_ff_destroy(input_dev);
err_free_mem:
    input_free_device(input_dev);
    kfree(vib);

    return error;
}

static int __devexit pm8xxx_vib_remove(struct platform_device *pdev)
{
    struct pm8xxx_vib *vib = platform_get_drvdata(pdev);

    input_unregister_device(vib->vib_input_dev);
    kfree(vib);

    platform_set_drvdata(pdev, NULL);

    return 0;
}

#ifdef CONFIG_PM_SLEEP
static int pm8xxx_vib_suspend(struct device *dev)
{
    struct pm8xxx_vib *vib = dev_get_drvdata(dev);

    /* Turn off the vibrator */
    pm8xxx_vib_set(vib, false);

    return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(pm8xxx_vib_pm_ops, pm8xxx_vib_suspend, NULL);

static struct platform_driver pm8xxx_vib_driver = {
    .probe      = pm8xxx_vib_probe,
    .remove     = __devexit_p(pm8xxx_vib_remove),
    .driver     = {
        .name   = "pm8xxx-vib",
        .owner  = THIS_MODULE,
        .pm = &pm8xxx_vib_pm_ops,
    },
};
module_platform_driver(pm8xxx_vib_driver);

MODULE_ALIAS("platform:pm8xxx_vib");
MODULE_DESCRIPTION("PMIC8xxx vibrator driver based on ff-memless framework");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Amy Maloche <[email protected]>");