gp2ap002a00f.c

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/*
 * Copyright (C) 2011 Sony Ericsson Mobile Communications Inc.
 *
 * Author: Courtney Cavin <[email protected]>
 * Prepared for up-stream by: Oskar Andero <[email protected]>
 *
 * 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.
 */

#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/input/gp2ap002a00f.h>

struct gp2a_data {
    struct input_dev *input;
    const struct gp2a_platform_data *pdata;
    struct i2c_client *i2c_client;
};

enum gp2a_addr {
    GP2A_ADDR_PROX  = 0x0,
    GP2A_ADDR_GAIN  = 0x1,
    GP2A_ADDR_HYS   = 0x2,
    GP2A_ADDR_CYCLE = 0x3,
    GP2A_ADDR_OPMOD = 0x4,
    GP2A_ADDR_CON   = 0x6
};

enum gp2a_controls {
    /* Software Shutdown control: 0 = shutdown, 1 = normal operation */
    GP2A_CTRL_SSD   = 0x01
};

static int gp2a_report(struct gp2a_data *dt)
{
    int vo = gpio_get_value(dt->pdata->vout_gpio);

    input_report_switch(dt->input, SW_FRONT_PROXIMITY, !vo);
    input_sync(dt->input);

    return 0;
}

static irqreturn_t gp2a_irq(int irq, void *handle)
{
    struct gp2a_data *dt = handle;

    gp2a_report(dt);

    return IRQ_HANDLED;
}

static int gp2a_enable(struct gp2a_data *dt)
{
    return i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_OPMOD,
                     GP2A_CTRL_SSD);
}

static int gp2a_disable(struct gp2a_data *dt)
{
    return i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_OPMOD,
                     0x00);
}

static int gp2a_device_open(struct input_dev *dev)
{
    struct gp2a_data *dt = input_get_drvdata(dev);
    int error;

    error = gp2a_enable(dt);
    if (error < 0) {
        dev_err(&dt->i2c_client->dev,
            "unable to activate, err %d\n", error);
        return error;
    }

    gp2a_report(dt);

    return 0;
}

static void gp2a_device_close(struct input_dev *dev)
{
    struct gp2a_data *dt = input_get_drvdata(dev);
    int error;

    error = gp2a_disable(dt);
    if (error < 0)
        dev_err(&dt->i2c_client->dev,
            "unable to deactivate, err %d\n", error);
}

static int __devinit gp2a_initialize(struct gp2a_data *dt)
{
    int error;

    error = i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_GAIN,
                      0x08);
    if (error < 0)
        return error;

    error = i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_HYS,
                      0xc2);
    if (error < 0)
        return error;

    error = i2c_smbus_write_byte_data(dt->i2c_client, GP2A_ADDR_CYCLE,
                      0x04);
    if (error < 0)
        return error;

    error = gp2a_disable(dt);

    return error;
}

static int __devinit gp2a_probe(struct i2c_client *client,
                const struct i2c_device_id *id)
{
    const struct gp2a_platform_data *pdata = client->dev.platform_data;
    struct gp2a_data *dt;
    int error;

    if (!pdata)
        return -EINVAL;

    if (pdata->hw_setup) {
        error = pdata->hw_setup(client);
        if (error < 0)
            return error;
    }

    error = gpio_request_one(pdata->vout_gpio, GPIOF_IN, GP2A_I2C_NAME);
    if (error)
        goto err_hw_shutdown;

    dt = kzalloc(sizeof(struct gp2a_data), GFP_KERNEL);
    if (!dt) {
        error = -ENOMEM;
        goto err_free_gpio;
    }

    dt->pdata = pdata;
    dt->i2c_client = client;

    error = gp2a_initialize(dt);
    if (error < 0)
        goto err_free_mem;

    dt->input = input_allocate_device();
    if (!dt->input) {
        error = -ENOMEM;
        goto err_free_mem;
    }

    input_set_drvdata(dt->input, dt);

    dt->input->open = gp2a_device_open;
    dt->input->close = gp2a_device_close;
    dt->input->name = GP2A_I2C_NAME;
    dt->input->id.bustype = BUS_I2C;
    dt->input->dev.parent = &client->dev;

    input_set_capability(dt->input, EV_SW, SW_FRONT_PROXIMITY);

    error = request_threaded_irq(client->irq, NULL, gp2a_irq,
            IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
                IRQF_ONESHOT,
            GP2A_I2C_NAME, dt);
    if (error) {
        dev_err(&client->dev, "irq request failed\n");
        goto err_free_input_dev;
    }

    error = input_register_device(dt->input);
    if (error) {
        dev_err(&client->dev, "device registration failed\n");
        goto err_free_irq;
    }

    device_init_wakeup(&client->dev, pdata->wakeup);
    i2c_set_clientdata(client, dt);

    return 0;

err_free_irq:
    free_irq(client->irq, dt);
err_free_input_dev:
    input_free_device(dt->input);
err_free_mem:
    kfree(dt);
err_free_gpio:
    gpio_free(pdata->vout_gpio);
err_hw_shutdown:
    if (pdata->hw_shutdown)
        pdata->hw_shutdown(client);
    return error;
}

static int __devexit gp2a_remove(struct i2c_client *client)
{
    struct gp2a_data *dt = i2c_get_clientdata(client);
    const struct gp2a_platform_data *pdata = dt->pdata;

    device_init_wakeup(&client->dev, false);

    free_irq(client->irq, dt);

    input_unregister_device(dt->input);
    kfree(dt);

    gpio_free(pdata->vout_gpio);

    if (pdata->hw_shutdown)
        pdata->hw_shutdown(client);

    return 0;
}

#ifdef CONFIG_PM_SLEEP
static int gp2a_suspend(struct device *dev)
{
    struct i2c_client *client = to_i2c_client(dev);
    struct gp2a_data *dt = i2c_get_clientdata(client);
    int retval = 0;

    if (device_may_wakeup(&client->dev)) {
        enable_irq_wake(client->irq);
    } else {
        mutex_lock(&dt->input->mutex);
        if (dt->input->users)
            retval = gp2a_disable(dt);
        mutex_unlock(&dt->input->mutex);
    }

    return retval;
}

static int gp2a_resume(struct device *dev)
{
    struct i2c_client *client = to_i2c_client(dev);
    struct gp2a_data *dt = i2c_get_clientdata(client);
    int retval = 0;

    if (device_may_wakeup(&client->dev)) {
        disable_irq_wake(client->irq);
    } else {
        mutex_lock(&dt->input->mutex);
        if (dt->input->users)
            retval = gp2a_enable(dt);
        mutex_unlock(&dt->input->mutex);
    }

    return retval;
}
#endif

static SIMPLE_DEV_PM_OPS(gp2a_pm, gp2a_suspend, gp2a_resume);

static const struct i2c_device_id gp2a_i2c_id[] = {
    { GP2A_I2C_NAME, 0 },
    { }
};

static struct i2c_driver gp2a_i2c_driver = {
    .driver = {
        .name   = GP2A_I2C_NAME,
        .owner  = THIS_MODULE,
        .pm = &gp2a_pm,
    },
    .probe      = gp2a_probe,
    .remove     = __devexit_p(gp2a_remove),
    .id_table   = gp2a_i2c_id,
};

module_i2c_driver(gp2a_i2c_driver);

MODULE_AUTHOR("Courtney Cavin <[email protected]>");
MODULE_DESCRIPTION("Sharp GP2AP002A00F I2C Proximity/Opto sensor driver");
MODULE_LICENSE("GPL v2");