lis3lv02d_spi.c

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/*
 * lis3lv02d_spi - SPI glue layer for lis3lv02d
 *
 * Copyright (c) 2009 Daniel Mack <[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
 *  publishhed by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/spi/spi.h>
#include <linux/pm.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/of_device.h>

#include "lis3lv02d.h"

#define DRV_NAME    "lis3lv02d_spi"
#define LIS3_SPI_READ   0x80

static int lis3_spi_read(struct lis3lv02d *lis3, int reg, u8 *v)
{
    struct spi_device *spi = lis3->bus_priv;
    int ret = spi_w8r8(spi, reg | LIS3_SPI_READ);
    if (ret < 0)
        return -EINVAL;

    *v = (u8) ret;
    return 0;
}

static int lis3_spi_write(struct lis3lv02d *lis3, int reg, u8 val)
{
    u8 tmp[2] = { reg, val };
    struct spi_device *spi = lis3->bus_priv;
    return spi_write(spi, tmp, sizeof(tmp));
}

static int lis3_spi_init(struct lis3lv02d *lis3)
{
    u8 reg;
    int ret;

    /* power up the device */
    ret = lis3->read(lis3, CTRL_REG1, &reg);
    if (ret < 0)
        return ret;

    reg |= CTRL1_PD0 | CTRL1_Xen | CTRL1_Yen | CTRL1_Zen;
    return lis3->write(lis3, CTRL_REG1, reg);
}

static union axis_conversion lis3lv02d_axis_normal =
    { .as_array = { 1, 2, 3 } };

#ifdef CONFIG_OF
static struct of_device_id lis302dl_spi_dt_ids[] = {
    { .compatible = "st,lis302dl-spi" },
    {}
};
MODULE_DEVICE_TABLE(of, lis302dl_spi_dt_ids);
#endif

static int __devinit lis302dl_spi_probe(struct spi_device *spi)
{
    int ret;

    spi->bits_per_word = 8;
    spi->mode = SPI_MODE_0;
    ret = spi_setup(spi);
    if (ret < 0)
        return ret;

    lis3_dev.bus_priv   = spi;
    lis3_dev.init       = lis3_spi_init;
    lis3_dev.read       = lis3_spi_read;
    lis3_dev.write      = lis3_spi_write;
    lis3_dev.irq        = spi->irq;
    lis3_dev.ac     = lis3lv02d_axis_normal;
    lis3_dev.pdata      = spi->dev.platform_data;

#ifdef CONFIG_OF
    if (of_match_device(lis302dl_spi_dt_ids, &spi->dev)) {
        lis3_dev.of_node = spi->dev.of_node;
        ret = lis3lv02d_init_dt(&lis3_dev);
        if (ret)
            return ret;
    }
#endif
    spi_set_drvdata(spi, &lis3_dev);

    return lis3lv02d_init_device(&lis3_dev);
}

static int __devexit lis302dl_spi_remove(struct spi_device *spi)
{
    struct lis3lv02d *lis3 = spi_get_drvdata(spi);
    lis3lv02d_joystick_disable(lis3);
    lis3lv02d_poweroff(lis3);

    return lis3lv02d_remove_fs(&lis3_dev);
}

#ifdef CONFIG_PM_SLEEP
static int lis3lv02d_spi_suspend(struct device *dev)
{
    struct spi_device *spi = to_spi_device(dev);
    struct lis3lv02d *lis3 = spi_get_drvdata(spi);

    if (!lis3->pdata || !lis3->pdata->wakeup_flags)
        lis3lv02d_poweroff(&lis3_dev);

    return 0;
}

static int lis3lv02d_spi_resume(struct device *dev)
{
    struct spi_device *spi = to_spi_device(dev);
    struct lis3lv02d *lis3 = spi_get_drvdata(spi);

    if (!lis3->pdata || !lis3->pdata->wakeup_flags)
        lis3lv02d_poweron(lis3);

    return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(lis3lv02d_spi_pm, lis3lv02d_spi_suspend,
             lis3lv02d_spi_resume);

static struct spi_driver lis302dl_spi_driver = {
    .driver  = {
        .name   = DRV_NAME,
        .owner  = THIS_MODULE,
        .pm = &lis3lv02d_spi_pm,
        .of_match_table = of_match_ptr(lis302dl_spi_dt_ids),
    },
    .probe  = lis302dl_spi_probe,
    .remove = __devexit_p(lis302dl_spi_remove),
};

module_spi_driver(lis302dl_spi_driver);

MODULE_AUTHOR("Daniel Mack <[email protected]>");
MODULE_DESCRIPTION("lis3lv02d SPI glue layer");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:" DRV_NAME);