1/*
2 * Power off driver for ams AS3722 device.
3 *
4 * Copyright (c) 2013, NVIDIA CORPORATION.  All rights reserved.
5 *
6 * Author: Laxman Dewangan <ldewangan@nvidia.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15 * more details.
16 */
17
18#include <linux/mfd/as3722.h>
19#include <linux/module.h>
20#include <linux/of.h>
21#include <linux/of_device.h>
22#include <linux/platform_device.h>
23#include <linux/slab.h>
24
25struct as3722_poweroff {
26	struct device *dev;
27	struct as3722 *as3722;
28};
29
30static struct as3722_poweroff *as3722_pm_poweroff;
31
32static void as3722_pm_power_off(void)
33{
34	int ret;
35
36	if (!as3722_pm_poweroff) {
37		pr_err("AS3722 poweroff is not initialised\n");
38		return;
39	}
40
41	ret = as3722_update_bits(as3722_pm_poweroff->as3722,
42		AS3722_RESET_CONTROL_REG, AS3722_POWER_OFF, AS3722_POWER_OFF);
43	if (ret < 0)
44		dev_err(as3722_pm_poweroff->dev,
45			"RESET_CONTROL_REG update failed, %d\n", ret);
46}
47
48static int as3722_poweroff_probe(struct platform_device *pdev)
49{
50	struct as3722_poweroff *as3722_poweroff;
51	struct device_node *np = pdev->dev.parent->of_node;
52
53	if (!np)
54		return -EINVAL;
55
56	if (!of_property_read_bool(np, "ams,system-power-controller"))
57		return 0;
58
59	as3722_poweroff = devm_kzalloc(&pdev->dev, sizeof(*as3722_poweroff),
60				GFP_KERNEL);
61	if (!as3722_poweroff)
62		return -ENOMEM;
63
64	as3722_poweroff->as3722 = dev_get_drvdata(pdev->dev.parent);
65	as3722_poweroff->dev = &pdev->dev;
66	as3722_pm_poweroff = as3722_poweroff;
67	if (!pm_power_off)
68		pm_power_off = as3722_pm_power_off;
69
70	return 0;
71}
72
73static int as3722_poweroff_remove(struct platform_device *pdev)
74{
75	if (pm_power_off == as3722_pm_power_off)
76		pm_power_off = NULL;
77	as3722_pm_poweroff = NULL;
78
79	return 0;
80}
81
82static struct platform_driver as3722_poweroff_driver = {
83	.driver = {
84		.name = "as3722-power-off",
85	},
86	.probe = as3722_poweroff_probe,
87	.remove = as3722_poweroff_remove,
88};
89
90module_platform_driver(as3722_poweroff_driver);
91
92MODULE_DESCRIPTION("Power off driver for ams AS3722 PMIC Device");
93MODULE_ALIAS("platform:as3722-power-off");
94MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
95MODULE_LICENSE("GPL v2");
96