/*
 * twl4030-vibra.c - TWL4030 Vibrator driver
 *
 * Copyright (C) 2008-2010 Nokia Corporation
 *
 * Written by Henrik Saari <henrik.saari@nokia.com>
 * Updates by Felipe Balbi <felipe.balbi@nokia.com>
 * Input by Jari Vanhala <ext-jari.vanhala@nokia.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License 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.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/workqueue.h>
#include <linux/i2c/twl.h>
#include <linux/mfd/twl4030-audio.h>
#include <linux/input.h>
#include <linux/slab.h>

/* MODULE ID2 */
#define LEDEN           0x00

/* ForceFeedback */
#define EFFECT_DIR_180_DEG      0x8000 /* range is 0 - 0xFFFF */

struct vibra_info {
        struct device           *dev;
        struct input_dev        *input_dev;

        struct work_struct      play_work;

        bool                    enabled;
        int                     speed;
        int                     direction;

        bool                    coexist;
};

static void vibra_disable_leds(void)
{
        u8 reg;

        /* Disable LEDA & LEDB, cannot be used with vibra (PWM) */
        twl_i2c_read_u8(TWL4030_MODULE_LED, &reg, LEDEN);
        reg &= ~0x03;
        twl_i2c_write_u8(TWL4030_MODULE_LED, LEDEN, reg);
}

/* Powers H-Bridge and enables audio clk */
static void vibra_enable(struct vibra_info *info)
{
        u8 reg;

        twl4030_audio_enable_resource(TWL4030_AUDIO_RES_POWER);

        /* turn H-Bridge on */
        twl_i2c_read_u8(TWL4030_MODULE_AUDIO_VOICE,
                        &reg, TWL4030_REG_VIBRA_CTL);
        twl_i2c_write_u8(TWL4030_MODULE_AUDIO_VOICE,
                         (reg | TWL4030_VIBRA_EN), TWL4030_REG_VIBRA_CTL);

        twl4030_audio_enable_resource(TWL4030_AUDIO_RES_APLL);

        info->enabled = true;
}

static void vibra_disable(struct vibra_info *info)
{
        u8 reg;

        /* Power down H-Bridge */
        twl_i2c_read_u8(TWL4030_MODULE_AUDIO_VOICE,
                        &reg, TWL4030_REG_VIBRA_CTL);
        twl_i2c_write_u8(TWL4030_MODULE_AUDIO_VOICE,
                         (reg & ~TWL4030_VIBRA_EN), TWL4030_REG_VIBRA_CTL);

        twl4030_audio_disable_resource(TWL4030_AUDIO_RES_APLL);
        twl4030_audio_disable_resource(TWL4030_AUDIO_RES_POWER);

        info->enabled = false;
}

static void vibra_play_work(struct work_struct *work)
{
        struct vibra_info *info = container_of(work,
                        struct vibra_info, play_work);
        int dir;
        int pwm;
        u8 reg;

        dir = info->direction;
        pwm = info->speed;

        twl_i2c_read_u8(TWL4030_MODULE_AUDIO_VOICE,
                        &reg, TWL4030_REG_VIBRA_CTL);
        if (pwm && (!info->coexist || !(reg & TWL4030_VIBRA_SEL))) {

                if (!info->enabled)
                        vibra_enable(info);

                /* set vibra rotation direction */
                twl_i2c_read_u8(TWL4030_MODULE_AUDIO_VOICE,
                                &reg, TWL4030_REG_VIBRA_CTL);
                reg = (dir) ? (reg | TWL4030_VIBRA_DIR) :
                        (reg & ~TWL4030_VIBRA_DIR);
                twl_i2c_write_u8(TWL4030_MODULE_AUDIO_VOICE,
                                 reg, TWL4030_REG_VIBRA_CTL);

                /* set PWM, 1 = max, 255 = min */
                twl_i2c_write_u8(TWL4030_MODULE_AUDIO_VOICE,
                                 256 - pwm, TWL4030_REG_VIBRA_SET);
        } else {
                if (info->enabled)
                        vibra_disable(info);
        }
}

/*** Input/ForceFeedback ***/

static int vibra_play(struct input_dev *input, void *data,
                      struct ff_effect *effect)
{
        struct vibra_info *info = input_get_drvdata(input);

        info->speed = effect->u.rumble.strong_magnitude >> 8;
        if (!info->speed)
                info->speed = effect->u.rumble.weak_magnitude >> 9;
        info->direction = effect->direction < EFFECT_DIR_180_DEG ? 0 : 1;
        schedule_work(&info->play_work);
        return 0;
}

static void twl4030_vibra_close(struct input_dev *input)
{
        struct vibra_info *info = input_get_drvdata(input);

        cancel_work_sync(&info->play_work);

        if (info->enabled)
                vibra_disable(info);
}

/*** Module ***/
static int __maybe_unused twl4030_vibra_suspend(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct vibra_info *info = platform_get_drvdata(pdev);

        if (info->enabled)
                vibra_disable(info);

        return 0;
}

static int __maybe_unused twl4030_vibra_resume(struct device *dev)
{
        vibra_disable_leds();
        return 0;
}

static SIMPLE_DEV_PM_OPS(twl4030_vibra_pm_ops,
                         twl4030_vibra_suspend, twl4030_vibra_resume);

static bool twl4030_vibra_check_coexist(struct twl4030_vibra_data *pdata,
                              struct device_node *node)
{
        if (pdata && pdata->coexist)
                return true;

        node = of_find_node_by_name(node, "codec");
        if (node) {
                of_node_put(node);
                return true;
        }

        return false;
}

static int twl4030_vibra_probe(struct platform_device *pdev)
{
        struct twl4030_vibra_data *pdata = dev_get_platdata(&pdev->dev);
        struct device_node *twl4030_core_node = pdev->dev.parent->of_node;
        struct vibra_info *info;
        int ret;

        if (!pdata && !twl4030_core_node) {
                dev_dbg(&pdev->dev, "platform_data not available\n");
                return -EINVAL;
        }

        info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
        if (!info)
                return -ENOMEM;

        info->dev = &pdev->dev;
        info->coexist = twl4030_vibra_check_coexist(pdata, twl4030_core_node);
        INIT_WORK(&info->play_work, vibra_play_work);

        info->input_dev = devm_input_allocate_device(&pdev->dev);
        if (info->input_dev == NULL) {
                dev_err(&pdev->dev, "couldn't allocate input device\n");
                return -ENOMEM;
        }

        input_set_drvdata(info->input_dev, info);

        info->input_dev->name = "twl4030:vibrator";
        info->input_dev->id.version = 1;
        info->input_dev->close = twl4030_vibra_close;
        __set_bit(FF_RUMBLE, info->input_dev->ffbit);

        ret = input_ff_create_memless(info->input_dev, NULL, vibra_play);
        if (ret < 0) {
                dev_dbg(&pdev->dev, "couldn't register vibrator to FF\n");
                return ret;
        }

        ret = input_register_device(info->input_dev);
        if (ret < 0) {
                dev_dbg(&pdev->dev, "couldn't register input device\n");
                goto err_iff;
        }

        vibra_disable_leds();

        platform_set_drvdata(pdev, info);
        return 0;

err_iff:
        input_ff_destroy(info->input_dev);
        return ret;
}

static struct platform_driver twl4030_vibra_driver = {
        .probe          = twl4030_vibra_probe,
        .driver         = {
                .name   = "twl4030-vibra",
                .pm     = &twl4030_vibra_pm_ops,
        },
};
module_platform_driver(twl4030_vibra_driver);

MODULE_ALIAS("platform:twl4030-vibra");
MODULE_DESCRIPTION("TWL4030 Vibra driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Nokia Corporation");