diff options
Diffstat (limited to 'arch/arm/mach-s3c2442/gta02-pm-gps.c')
| -rw-r--r-- | arch/arm/mach-s3c2442/gta02-pm-gps.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c2442/gta02-pm-gps.c b/arch/arm/mach-s3c2442/gta02-pm-gps.c new file mode 100644 index 00000000000..2b71b7e4811 --- /dev/null +++ b/arch/arm/mach-s3c2442/gta02-pm-gps.c @@ -0,0 +1,246 @@ +/* + * 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/gpio-fns.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_GPH(4), S3C2410_GPH4_TXD1); + /* remove pulldown now it won't be floating any more */ + s3c2410_gpio_pullup(S3C2410_GPH(5), 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_GPH(4), S3C2410_GPIO_OUTPUT); + s3c2410_gpio_setpin(S3C2410_GPH(4), 0); + /* don't let RX from unpowered GPS float */ + s3c2410_gpio_pullup(S3C2410_GPH(5), 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 device *dev) +{ + if (!gta02_gps.keep_on_in_suspend || + !gta02_gps.power_was_on) + gps_pwron_set(0); + else + dev_warn(dev, "GTA02: keeping gps ON " + "during suspend\n"); + return 0; +} + +static int gta02_pm_gps_resume(struct device *dev) +{ + 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); + +static struct dev_pm_ops gta02_gps_pm_ops = { + .suspend = gta02_pm_gps_suspend, + .resume = gta02_pm_gps_resume, +}; + +#define GTA02_GPS_PM_OPS (>a02_gps_pm_ops) + +#else +#define GTA02_GPS_PM_OPS 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_GPH(4), S3C2410_GPIO_OUTPUT); + s3c2410_gpio_setpin(S3C2410_GPH(4), 0); + /* don't let RX from unpowered GPS float */ + s3c2410_gpio_pullup(S3C2410_GPH(5), 1); + + return sysfs_create_group(&pdev->dev.kobj, + >a02_gps_attr_group); +} + +static int gta02_pm_gps_remove(struct platform_device *pdev) +{ + regulator_put(gta02_gps.regulator); + sysfs_remove_group(&pdev->dev.kobj, >a02_gps_attr_group); + return 0; +} + +static struct platform_driver gta02_pm_gps_driver = { + .probe = gta02_pm_gps_probe, + .remove = gta02_pm_gps_remove, + .driver = { + .name = "gta02-pm-gps", + .pm = GTA02_GPS_PM_OPS, + }, +}; + +static int __devinit gta02_pm_gps_init(void) +{ + return platform_driver_register(>a02_pm_gps_driver); +} +module_init(gta02_pm_gps_init); + +static void gta02_pm_gps_exit(void) +{ + platform_driver_unregister(>a02_pm_gps_driver); +} +module_exit(gta02_pm_gps_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Harald Welte <laforge@openmoko.org>"); |