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/of_device.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16
17 struct as3722_poweroff {
18 struct device *dev;
19 struct as3722 *as3722;
20 };
21
22 static struct as3722_poweroff *as3722_pm_poweroff;
23
as3722_pm_power_off(void)24 static void as3722_pm_power_off(void)
25 {
26 int ret;
27
28 if (!as3722_pm_poweroff) {
29 pr_err("AS3722 poweroff is not initialised\n");
30 return;
31 }
32
33 ret = as3722_update_bits(as3722_pm_poweroff->as3722,
34 AS3722_RESET_CONTROL_REG, AS3722_POWER_OFF, AS3722_POWER_OFF);
35 if (ret < 0)
36 dev_err(as3722_pm_poweroff->dev,
37 "RESET_CONTROL_REG update failed, %d\n", ret);
38 }
39
as3722_poweroff_probe(struct platform_device * pdev)40 static int as3722_poweroff_probe(struct platform_device *pdev)
41 {
42 struct as3722_poweroff *as3722_poweroff;
43 struct device_node *np = pdev->dev.parent->of_node;
44
45 if (!np)
46 return -EINVAL;
47
48 if (!of_property_read_bool(np, "ams,system-power-controller"))
49 return 0;
50
51 as3722_poweroff = devm_kzalloc(&pdev->dev, sizeof(*as3722_poweroff),
52 GFP_KERNEL);
53 if (!as3722_poweroff)
54 return -ENOMEM;
55
56 as3722_poweroff->as3722 = dev_get_drvdata(pdev->dev.parent);
57 as3722_poweroff->dev = &pdev->dev;
58 as3722_pm_poweroff = as3722_poweroff;
59 if (!pm_power_off)
60 pm_power_off = as3722_pm_power_off;
61
62 return 0;
63 }
64
as3722_poweroff_remove(struct platform_device * pdev)65 static int as3722_poweroff_remove(struct platform_device *pdev)
66 {
67 if (pm_power_off == as3722_pm_power_off)
68 pm_power_off = NULL;
69 as3722_pm_poweroff = NULL;
70
71 return 0;
72 }
73
74 static struct platform_driver as3722_poweroff_driver = {
75 .driver = {
76 .name = "as3722-power-off",
77 },
78 .probe = as3722_poweroff_probe,
79 .remove = as3722_poweroff_remove,
80 };
81
82 module_platform_driver(as3722_poweroff_driver);
83
84 MODULE_DESCRIPTION("Power off driver for ams AS3722 PMIC Device");
85 MODULE_ALIAS("platform:as3722-power-off");
86 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
87 MODULE_LICENSE("GPL v2");
88