xref: /linux/drivers/power/reset/as3722-poweroff.c (revision 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Power off driver for ams AS3722 device.
4  *
5  * Copyright (c) 2013, NVIDIA CORPORATION.  All rights reserved.
6  *
7  * Author: Laxman Dewangan <ldewangan@nvidia.com>
8  */
9 
10 #include <linux/mfd/as3722.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/platform_device.h>
14 #include <linux/reboot.h>
15 #include <linux/slab.h>
16 
17 struct as3722_poweroff {
18 	struct device *dev;
19 	struct as3722 *as3722;
20 };
21 
22 static int as3722_pm_power_off(struct sys_off_data *data)
23 {
24 	struct as3722_poweroff *as3722_pm_poweroff = data->cb_data;
25 	int ret;
26 
27 	ret = as3722_update_bits(as3722_pm_poweroff->as3722,
28 		AS3722_RESET_CONTROL_REG, AS3722_POWER_OFF, AS3722_POWER_OFF);
29 	if (ret < 0)
30 		dev_err(as3722_pm_poweroff->dev,
31 			"RESET_CONTROL_REG update failed, %d\n", ret);
32 
33 	return NOTIFY_DONE;
34 }
35 
36 static int as3722_poweroff_probe(struct platform_device *pdev)
37 {
38 	struct as3722_poweroff *as3722_poweroff;
39 	struct device_node *np = pdev->dev.parent->of_node;
40 
41 	if (!np)
42 		return -EINVAL;
43 
44 	if (!of_property_read_bool(np, "ams,system-power-controller"))
45 		return 0;
46 
47 	as3722_poweroff = devm_kzalloc(&pdev->dev, sizeof(*as3722_poweroff),
48 				GFP_KERNEL);
49 	if (!as3722_poweroff)
50 		return -ENOMEM;
51 
52 	as3722_poweroff->as3722 = dev_get_drvdata(pdev->dev.parent);
53 	as3722_poweroff->dev = &pdev->dev;
54 
55 	return devm_register_sys_off_handler(as3722_poweroff->dev,
56 					     SYS_OFF_MODE_POWER_OFF,
57 					     SYS_OFF_PRIO_DEFAULT,
58 					     as3722_pm_power_off,
59 					     as3722_poweroff);
60 
61 	return 0;
62 }
63 
64 static struct platform_driver as3722_poweroff_driver = {
65 	.driver = {
66 		.name = "as3722-power-off",
67 	},
68 	.probe = as3722_poweroff_probe,
69 };
70 
71 module_platform_driver(as3722_poweroff_driver);
72 
73 MODULE_DESCRIPTION("Power off driver for ams AS3722 PMIC Device");
74 MODULE_ALIAS("platform:as3722-power-off");
75 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
76