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