drivers/misc/lis3lv02d/lis3lv02d_spi.c

/*
 * lis3lv02d_spi - SPI glue layer for lis3lv02d
 *
 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
 *
 *  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/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 const struct of_device_id lis302dl_spi_dt_ids[] = {
	{ .compatible = "st,lis302dl-spi" },
	{}
};
MODULE_DEVICE_TABLE(of, lis302dl_spi_dt_ids);
#endif

static int 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 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,
		.pm	= &lis3lv02d_spi_pm,
		.of_match_table = of_match_ptr(lis302dl_spi_dt_ids),
	},
	.probe	= lis302dl_spi_probe,
	.remove	= lis302dl_spi_remove,
};

module_spi_driver(lis302dl_spi_driver);

MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
MODULE_DESCRIPTION("lis3lv02d SPI glue layer");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:" DRV_NAME);