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