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linux/drivers/hwmon/lis3lv02d_spi.c
Daniel Mack 2cd9645e2f lis3: add power management functions
This enabled power management functions for the SPI transport layer of the
lis3 devices.  The device's suspend mode is only entered in case no wakeup
threshold has been given.  In this case, the device is supposed to wake up
the system and must thus not be put to deep sleep.

[randy.dunlap@oracle.com: fix lis3-spi for CONFIG_PM=n]
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Eric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:49 -07:00

144 lines
3.0 KiB
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/init.h>
#include <linux/err.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/spi/spi.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;
return lis3->write(lis3, CTRL_REG1, reg);
}
static struct axis_conversion lis3lv02d_axis_normal = { 1, 2, 3 };
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;
spi_set_drvdata(spi, &lis3_dev);
ret = lis3lv02d_init_device(&lis3_dev);
return ret;
}
static int __devexit lis302dl_spi_remove(struct spi_device *spi)
{
struct lis3lv02d *lis3 = spi_get_drvdata(spi);
lis3lv02d_joystick_disable();
lis3lv02d_poweroff(lis3);
return 0;
}
#ifdef CONFIG_PM
static int lis3lv02d_spi_suspend(struct spi_device *spi, pm_message_t mesg)
{
struct lis3lv02d *lis3 = spi_get_drvdata(spi);
if (!lis3->pdata->wakeup_flags)
lis3lv02d_poweroff(&lis3_dev);
return 0;
}
static int lis3lv02d_spi_resume(struct spi_device *spi)
{
struct lis3lv02d *lis3 = spi_get_drvdata(spi);
if (!lis3->pdata->wakeup_flags)
lis3lv02d_poweron(lis3);
return 0;
}
#else
#define lis3lv02d_spi_suspend NULL
#define lis3lv02d_spi_resume NULL
#endif
static struct spi_driver lis302dl_spi_driver = {
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
},
.probe = lis302dl_spi_probe,
.remove = __devexit_p(lis302dl_spi_remove),
.suspend = lis3lv02d_spi_suspend,
.resume = lis3lv02d_spi_resume,
};
static int __init lis302dl_init(void)
{
return spi_register_driver(&lis302dl_spi_driver);
}
static void __exit lis302dl_exit(void)
{
spi_unregister_driver(&lis302dl_spi_driver);
}
module_init(lis302dl_init);
module_exit(lis302dl_exit);
MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
MODULE_DESCRIPTION("lis3lv02d SPI glue layer");
MODULE_LICENSE("GPL");