diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/power/reset/gpio-poweroff.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/power/reset/gpio-poweroff.c')
-rw-r--r-- | kernel/drivers/power/reset/gpio-poweroff.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/kernel/drivers/power/reset/gpio-poweroff.c b/kernel/drivers/power/reset/gpio-poweroff.c new file mode 100644 index 000000000..e5332f1db --- /dev/null +++ b/kernel/drivers/power/reset/gpio-poweroff.c @@ -0,0 +1,111 @@ +/* + * Toggles a GPIO pin to power down a device + * + * Jamie Lentin <jm@lentin.co.uk> + * Andrew Lunn <andrew@lunn.ch> + * + * Copyright (C) 2012 Jamie Lentin + * + * 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/kernel.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/gpio/consumer.h> +#include <linux/of_platform.h> +#include <linux/module.h> + +/* + * Hold configuration here, cannot be more than one instance of the driver + * since pm_power_off itself is global. + */ +static struct gpio_desc *reset_gpio; + +static void gpio_poweroff_do_poweroff(void) +{ + BUG_ON(!reset_gpio); + + /* drive it active, also inactive->active edge */ + gpiod_direction_output(reset_gpio, 1); + mdelay(100); + /* drive inactive, also active->inactive edge */ + gpiod_set_value(reset_gpio, 0); + mdelay(100); + + /* drive it active, also inactive->active edge */ + gpiod_set_value(reset_gpio, 1); + + /* give it some time */ + mdelay(3000); + + WARN_ON(1); +} + +static int gpio_poweroff_probe(struct platform_device *pdev) +{ + bool input = false; + + /* If a pm_power_off function has already been added, leave it alone */ + if (pm_power_off != NULL) { + dev_err(&pdev->dev, + "%s: pm_power_off function already registered", + __func__); + return -EBUSY; + } + + reset_gpio = devm_gpiod_get(&pdev->dev, NULL); + if (IS_ERR(reset_gpio)) + return PTR_ERR(reset_gpio); + + input = of_property_read_bool(pdev->dev.of_node, "input"); + + if (input) { + if (gpiod_direction_input(reset_gpio)) { + dev_err(&pdev->dev, + "Could not set direction of reset GPIO to input\n"); + return -ENODEV; + } + } else { + if (gpiod_direction_output(reset_gpio, 0)) { + dev_err(&pdev->dev, + "Could not set direction of reset GPIO\n"); + return -ENODEV; + } + } + + pm_power_off = &gpio_poweroff_do_poweroff; + return 0; +} + +static int gpio_poweroff_remove(struct platform_device *pdev) +{ + if (pm_power_off == &gpio_poweroff_do_poweroff) + pm_power_off = NULL; + + return 0; +} + +static const struct of_device_id of_gpio_poweroff_match[] = { + { .compatible = "gpio-poweroff", }, + {}, +}; + +static struct platform_driver gpio_poweroff_driver = { + .probe = gpio_poweroff_probe, + .remove = gpio_poweroff_remove, + .driver = { + .name = "poweroff-gpio", + .of_match_table = of_gpio_poweroff_match, + }, +}; + +module_platform_driver(gpio_poweroff_driver); + +MODULE_AUTHOR("Jamie Lentin <jm@lentin.co.uk>"); +MODULE_DESCRIPTION("GPIO poweroff driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:poweroff-gpio"); |