linux/drivers/power/reset/as3722-poweroff.c

97 lines
2.4 KiB
C

/*
* Power off driver for ams AS3722 device.
*
* Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved.
*
* Author: Laxman Dewangan <ldewangan@nvidia.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#include <linux/mfd/as3722.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
struct as3722_poweroff {
struct device *dev;
struct as3722 *as3722;
};
static struct as3722_poweroff *as3722_pm_poweroff;
static void as3722_pm_power_off(void)
{
int ret;
if (!as3722_pm_poweroff) {
pr_err("AS3722 poweroff is not initialised\n");
return;
}
ret = as3722_update_bits(as3722_pm_poweroff->as3722,
AS3722_RESET_CONTROL_REG, AS3722_POWER_OFF, AS3722_POWER_OFF);
if (ret < 0)
dev_err(as3722_pm_poweroff->dev,
"RESET_CONTROL_REG update failed, %d\n", ret);
}
static int as3722_poweroff_probe(struct platform_device *pdev)
{
struct as3722_poweroff *as3722_poweroff;
struct device_node *np = pdev->dev.parent->of_node;
if (!np)
return -EINVAL;
if (!of_property_read_bool(np, "ams,system-power-controller"))
return 0;
as3722_poweroff = devm_kzalloc(&pdev->dev, sizeof(*as3722_poweroff),
GFP_KERNEL);
if (!as3722_poweroff)
return -ENOMEM;
as3722_poweroff->as3722 = dev_get_drvdata(pdev->dev.parent);
as3722_poweroff->dev = &pdev->dev;
as3722_pm_poweroff = as3722_poweroff;
if (!pm_power_off)
pm_power_off = as3722_pm_power_off;
return 0;
}
static int as3722_poweroff_remove(struct platform_device *pdev)
{
if (pm_power_off == as3722_pm_power_off)
pm_power_off = NULL;
as3722_pm_poweroff = NULL;
return 0;
}
static struct platform_driver as3722_poweroff_driver = {
.driver = {
.name = "as3722-power-off",
.owner = THIS_MODULE,
},
.probe = as3722_poweroff_probe,
.remove = as3722_poweroff_remove,
};
module_platform_driver(as3722_poweroff_driver);
MODULE_DESCRIPTION("Power off driver for ams AS3722 PMIC Device");
MODULE_ALIAS("platform:as3722-power-off");
MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
MODULE_LICENSE("GPL v2");