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 #define GEN1_REASON_SHIFT 2
18 #define GEN2_REASON_SHIFT 1
19
20 #define NO_REASON_SHIFT 0
21
22 struct pm8916_pon {
23 struct device *dev;
24 struct regmap *regmap;
25 u32 baseaddr;
26 struct reboot_mode_driver reboot_mode;
27 long reason_shift;
28 };
29
pm8916_reboot_mode_write(struct reboot_mode_driver * reboot,unsigned int magic)30 static int pm8916_reboot_mode_write(struct reboot_mode_driver *reboot,
31 unsigned int magic)
32 {
33 struct pm8916_pon *pon = container_of
34 (reboot, struct pm8916_pon, reboot_mode);
35 int ret;
36
37 ret = regmap_update_bits(pon->regmap,
38 pon->baseaddr + PON_SOFT_RB_SPARE,
39 GENMASK(7, pon->reason_shift),
40 magic << pon->reason_shift);
41 if (ret < 0)
42 dev_err(pon->dev, "update reboot mode bits failed\n");
43
44 return ret;
45 }
46
pm8916_pon_probe(struct platform_device * pdev)47 static int pm8916_pon_probe(struct platform_device *pdev)
48 {
49 struct pm8916_pon *pon;
50 long reason_shift;
51 int error;
52
53 pon = devm_kzalloc(&pdev->dev, sizeof(*pon), GFP_KERNEL);
54 if (!pon)
55 return -ENOMEM;
56
57 pon->dev = &pdev->dev;
58
59 pon->regmap = dev_get_regmap(pdev->dev.parent, NULL);
60 if (!pon->regmap) {
61 dev_err(&pdev->dev, "failed to locate regmap\n");
62 return -ENODEV;
63 }
64
65 error = of_property_read_u32(pdev->dev.of_node, "reg",
66 &pon->baseaddr);
67 if (error)
68 return error;
69
70 reason_shift = (long)of_device_get_match_data(&pdev->dev);
71
72 if (reason_shift != NO_REASON_SHIFT) {
73 pon->reboot_mode.dev = &pdev->dev;
74 pon->reason_shift = reason_shift;
75 pon->reboot_mode.write = pm8916_reboot_mode_write;
76 error = devm_reboot_mode_register(&pdev->dev, &pon->reboot_mode);
77 if (error) {
78 dev_err(&pdev->dev, "can't register reboot mode\n");
79 return error;
80 }
81 }
82
83 platform_set_drvdata(pdev, pon);
84
85 return devm_of_platform_populate(&pdev->dev);
86 }
87
88 static const struct of_device_id pm8916_pon_id_table[] = {
89 { .compatible = "qcom,pm8916-pon", .data = (void *)GEN1_REASON_SHIFT },
90 { .compatible = "qcom,pm8941-pon", .data = (void *)NO_REASON_SHIFT },
91 { .compatible = "qcom,pms405-pon", .data = (void *)GEN1_REASON_SHIFT },
92 { .compatible = "qcom,pm8998-pon", .data = (void *)GEN2_REASON_SHIFT },
93 { .compatible = "qcom,pmk8350-pon", .data = (void *)GEN2_REASON_SHIFT },
94 { }
95 };
96 MODULE_DEVICE_TABLE(of, pm8916_pon_id_table);
97
98 static struct platform_driver pm8916_pon_driver = {
99 .probe = pm8916_pon_probe,
100 .driver = {
101 .name = "pm8916-pon",
102 .of_match_table = pm8916_pon_id_table,
103 },
104 };
105 module_platform_driver(pm8916_pon_driver);
106
107 MODULE_DESCRIPTION("pm8916 Power On driver");
108 MODULE_LICENSE("GPL v2");
109