wifipineapple-openwrt/target/linux/s3c24xx/files-2.6.30/arch/arm/mach-s3c2442/gta02-pm-gps.c

243 lines
5.9 KiB
C

/*
* GPS Power Management code for the Openmoko Freerunner GSM Phone
*
* (C) 2007-2009 by Openmoko Inc.
* Author: Harald Welte <laforge@openmoko.org>
* All rights reserved.
*
* 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/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <mach/hardware.h>
#include <mach/cpu.h>
#include <asm/mach-types.h>
#include <mach/gta02.h>
#include <linux/mfd/pcf50633/core.h>
#include <linux/mfd/pcf50633/pmic.h>
#include <linux/regulator/consumer.h>
#include <linux/err.h>
struct gta02_pm_gps_data {
#ifdef CONFIG_PM
int keep_on_in_suspend;
#endif
int power_was_on;
struct regulator *regulator;
};
static struct gta02_pm_gps_data gta02_gps;
int gta02_pm_gps_is_on(void)
{
return gta02_gps.power_was_on;
}
EXPORT_SYMBOL_GPL(gta02_pm_gps_is_on);
/* This is the POWERON pin */
static void gps_pwron_set(int on)
{
if (on) {
/* return UART pins to being UART pins */
s3c2410_gpio_cfgpin(S3C2410_GPH4, S3C2410_GPH4_TXD1);
/* remove pulldown now it won't be floating any more */
s3c2410_gpio_pullup(S3C2410_GPH5, 0);
if (!gta02_gps.power_was_on)
regulator_enable(gta02_gps.regulator);
} else {
/*
* take care not to power unpowered GPS from UART TX
* return them to GPIO and force low
*/
s3c2410_gpio_cfgpin(S3C2410_GPH4, S3C2410_GPH4_OUTP);
s3c2410_gpio_setpin(S3C2410_GPH4, 0);
/* don't let RX from unpowered GPS float */
s3c2410_gpio_pullup(S3C2410_GPH5, 1);
if (gta02_gps.power_was_on)
regulator_disable(gta02_gps.regulator);
}
}
static int gps_pwron_get(void)
{
return regulator_is_enabled(gta02_gps.regulator);
}
#ifdef CONFIG_PM
/* This is the flag for keeping gps ON during suspend */
static void gps_keep_on_in_suspend_set(int on)
{
gta02_gps.keep_on_in_suspend = on;
}
static int gps_keep_on_in_suspend_get(void)
{
return gta02_gps.keep_on_in_suspend;
}
#endif
static ssize_t power_gps_read(struct device *dev,
struct device_attribute *attr, char *buf)
{
int ret = 0;
if (!strcmp(attr->attr.name, "power_on") ||
!strcmp(attr->attr.name, "pwron")) {
ret = gps_pwron_get();
#ifdef CONFIG_PM
} else if (!strcmp(attr->attr.name, "keep_on_in_suspend")) {
ret = gps_keep_on_in_suspend_get();
#endif
}
if (ret)
return strlcpy(buf, "1\n", 3);
else
return strlcpy(buf, "0\n", 3);
}
static ssize_t power_gps_write(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
{
unsigned long on = simple_strtoul(buf, NULL, 10);
if (!strcmp(attr->attr.name, "power_on") ||
!strcmp(attr->attr.name, "pwron")) {
gps_pwron_set(on);
gta02_gps.power_was_on = !!on;
#ifdef CONFIG_PM
} else if (!strcmp(attr->attr.name, "keep_on_in_suspend")) {
gps_keep_on_in_suspend_set(on);
#endif
}
return count;
}
#ifdef CONFIG_PM
static int gta02_pm_gps_suspend(struct platform_device *pdev,
pm_message_t state)
{
if (!gta02_gps.keep_on_in_suspend ||
!gta02_gps.power_was_on)
gps_pwron_set(0);
else
dev_warn(&pdev->dev, "GTA02: keeping gps ON "
"during suspend\n");
return 0;
}
static int gta02_pm_gps_resume(struct platform_device *pdev)
{
if (!gta02_gps.keep_on_in_suspend && gta02_gps.power_was_on)
gps_pwron_set(1);
return 0;
}
static DEVICE_ATTR(keep_on_in_suspend, 0644, power_gps_read, power_gps_write);
#else
#define gta02_pm_gps_suspend NULL
#define gta02_pm_gps_resume NULL
#endif
static DEVICE_ATTR(power_on, 0644, power_gps_read, power_gps_write);
static struct attribute *gta02_gps_sysfs_entries[] = {
&dev_attr_power_on.attr,
#ifdef CONFIG_PM
&dev_attr_keep_on_in_suspend.attr,
#endif
NULL
};
static struct attribute_group gta02_gps_attr_group = {
.name = NULL,
.attrs = gta02_gps_sysfs_entries,
};
static int __init gta02_pm_gps_probe(struct platform_device *pdev)
{
gta02_gps.regulator = regulator_get(&pdev->dev, "RF_3V");
if (IS_ERR(gta02_gps.regulator)) {
dev_err(&pdev->dev, "probe failed %ld\n",
PTR_ERR(gta02_gps.regulator));
return PTR_ERR(gta02_gps.regulator);
}
dev_info(&pdev->dev, "starting\n");
/*
* Here we should call the code that handles the set GPS power
* off action. But, the regulator API does not allow us to
* reassert regulator state, and when we read the regulator API
* logical state, it can differ from the actual state, So
* a workaround for this is to just set the regulator off in the
* PMU directly. Because that's different from normal flow, we
* have to reproduce other things from the OFF action here too.
*/
/*
* u-boot enables LDO5 (GPS), which doesn't make sense and
* causes confusion. We therefore disable the regulator here.
*/
pcf50633_reg_write(gta02_pcf, PCF50633_REG_LDO5ENA, 0);
/*
* take care not to power unpowered GPS from UART TX
* return them to GPIO and force low
*/
s3c2410_gpio_cfgpin(S3C2410_GPH4, S3C2410_GPH4_OUTP);
s3c2410_gpio_setpin(S3C2410_GPH4, 0);
/* don't let RX from unpowered GPS float */
s3c2410_gpio_pullup(S3C2410_GPH5, 1);
return sysfs_create_group(&pdev->dev.kobj,
&gta02_gps_attr_group);
}
static int gta02_pm_gps_remove(struct platform_device *pdev)
{
regulator_put(gta02_gps.regulator);
sysfs_remove_group(&pdev->dev.kobj, &gta02_gps_attr_group);
return 0;
}
static struct platform_driver gta02_pm_gps_driver = {
.probe = gta02_pm_gps_probe,
.remove = gta02_pm_gps_remove,
.suspend = gta02_pm_gps_suspend,
.resume = gta02_pm_gps_resume,
.driver = {
.name = "gta02-pm-gps",
},
};
static int __devinit gta02_pm_gps_init(void)
{
return platform_driver_register(&gta02_pm_gps_driver);
}
static void gta02_pm_gps_exit(void)
{
platform_driver_unregister(&gta02_pm_gps_driver);
}
module_init(gta02_pm_gps_init);
module_exit(gta02_pm_gps_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@openmoko.org>");