1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-18 Linaro Limited
3
4 #include <linux/delay.h>
5 #include <linux/errno.h>
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/of.h>
9 #include <linux/of_platform.h>
10 #include <linux/platform_device.h>
11 #include <linux/reboot.h>
12 #include <linux/reboot-mode.h>
13 #include <linux/regmap.h>
14
15 #define PON_SOFT_RB_SPARE 0x8f
16
17 struct pm8916_pon {
18 struct device *dev;
19 struct regmap *regmap;
20 u32 baseaddr;
21 struct reboot_mode_driver reboot_mode;
22 };
23
pm8916_reboot_mode_write(struct reboot_mode_driver * reboot,unsigned int magic)24 static int pm8916_reboot_mode_write(struct reboot_mode_driver *reboot,
25 unsigned int magic)
26 {
27 struct pm8916_pon *pon = container_of
28 (reboot, struct pm8916_pon, reboot_mode);
29 int ret;
30
31 ret = regmap_update_bits(pon->regmap,
32 pon->baseaddr + PON_SOFT_RB_SPARE,
33 0xfc, magic << 2);
34 if (ret < 0)
35 dev_err(pon->dev, "update reboot mode bits failed\n");
36
37 return ret;
38 }
39
pm8916_pon_probe(struct platform_device * pdev)40 static int pm8916_pon_probe(struct platform_device *pdev)
41 {
42 struct pm8916_pon *pon;
43 int error;
44
45 pon = devm_kzalloc(&pdev->dev, sizeof(*pon), GFP_KERNEL);
46 if (!pon)
47 return -ENOMEM;
48
49 pon->dev = &pdev->dev;
50
51 pon->regmap = dev_get_regmap(pdev->dev.parent, NULL);
52 if (!pon->regmap) {
53 dev_err(&pdev->dev, "failed to locate regmap\n");
54 return -ENODEV;
55 }
56
57 error = of_property_read_u32(pdev->dev.of_node, "reg",
58 &pon->baseaddr);
59 if (error)
60 return error;
61
62 pon->reboot_mode.dev = &pdev->dev;
63 pon->reboot_mode.write = pm8916_reboot_mode_write;
64 error = devm_reboot_mode_register(&pdev->dev, &pon->reboot_mode);
65 if (error) {
66 dev_err(&pdev->dev, "can't register reboot mode\n");
67 return error;
68 }
69
70 platform_set_drvdata(pdev, pon);
71
72 return devm_of_platform_populate(&pdev->dev);
73 }
74
75 static const struct of_device_id pm8916_pon_id_table[] = {
76 { .compatible = "qcom,pm8916-pon" },
77 { }
78 };
79 MODULE_DEVICE_TABLE(of, pm8916_pon_id_table);
80
81 static struct platform_driver pm8916_pon_driver = {
82 .probe = pm8916_pon_probe,
83 .driver = {
84 .name = "pm8916-pon",
85 .of_match_table = of_match_ptr(pm8916_pon_id_table),
86 },
87 };
88 module_platform_driver(pm8916_pon_driver);
89
90 MODULE_DESCRIPTION("pm8916 Power On driver");
91 MODULE_LICENSE("GPL v2");
92
