1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018 Spreadtrum Communications Inc.
4  */
5 
6 #include <linux/module.h>
7 #include <linux/of_address.h>
8 #include <linux/platform_device.h>
9 #include <linux/regmap.h>
10 #include <linux/input.h>
11 #include <linux/workqueue.h>
12 
13 #define CUR_DRV_CAL_SEL		GENMASK(13, 12)
14 #define SLP_LDOVIBR_PD_EN	BIT(9)
15 #define LDO_VIBR_PD		BIT(8)
16 
17 struct vibra_info {
18 	struct input_dev	*input_dev;
19 	struct work_struct	play_work;
20 	struct regmap		*regmap;
21 	u32			base;
22 	u32			strength;
23 	bool			enabled;
24 };
25 
26 static void sc27xx_vibra_set(struct vibra_info *info, bool on)
27 {
28 	if (on) {
29 		regmap_update_bits(info->regmap, info->base, LDO_VIBR_PD, 0);
30 		regmap_update_bits(info->regmap, info->base,
31 				   SLP_LDOVIBR_PD_EN, 0);
32 		info->enabled = true;
33 	} else {
34 		regmap_update_bits(info->regmap, info->base, LDO_VIBR_PD,
35 				   LDO_VIBR_PD);
36 		regmap_update_bits(info->regmap, info->base,
37 				   SLP_LDOVIBR_PD_EN, SLP_LDOVIBR_PD_EN);
38 		info->enabled = false;
39 	}
40 }
41 
42 static int sc27xx_vibra_hw_init(struct vibra_info *info)
43 {
44 	return regmap_update_bits(info->regmap, info->base, CUR_DRV_CAL_SEL, 0);
45 }
46 
47 static void sc27xx_vibra_play_work(struct work_struct *work)
48 {
49 	struct vibra_info *info = container_of(work, struct vibra_info,
50 					       play_work);
51 
52 	if (info->strength && !info->enabled)
53 		sc27xx_vibra_set(info, true);
54 	else if (info->strength == 0 && info->enabled)
55 		sc27xx_vibra_set(info, false);
56 }
57 
58 static int sc27xx_vibra_play(struct input_dev *input, void *data,
59 			     struct ff_effect *effect)
60 {
61 	struct vibra_info *info = input_get_drvdata(input);
62 
63 	info->strength = effect->u.rumble.weak_magnitude;
64 	schedule_work(&info->play_work);
65 
66 	return 0;
67 }
68 
69 static void sc27xx_vibra_close(struct input_dev *input)
70 {
71 	struct vibra_info *info = input_get_drvdata(input);
72 
73 	cancel_work_sync(&info->play_work);
74 	if (info->enabled)
75 		sc27xx_vibra_set(info, false);
76 }
77 
78 static int sc27xx_vibra_probe(struct platform_device *pdev)
79 {
80 	struct vibra_info *info;
81 	int error;
82 
83 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
84 	if (!info)
85 		return -ENOMEM;
86 
87 	info->regmap = dev_get_regmap(pdev->dev.parent, NULL);
88 	if (!info->regmap) {
89 		dev_err(&pdev->dev, "failed to get vibrator regmap.\n");
90 		return -ENODEV;
91 	}
92 
93 	error = device_property_read_u32(&pdev->dev, "reg", &info->base);
94 	if (error) {
95 		dev_err(&pdev->dev, "failed to get vibrator base address.\n");
96 		return error;
97 	}
98 
99 	info->input_dev = devm_input_allocate_device(&pdev->dev);
100 	if (!info->input_dev) {
101 		dev_err(&pdev->dev, "failed to allocate input device.\n");
102 		return -ENOMEM;
103 	}
104 
105 	info->input_dev->name = "sc27xx:vibrator";
106 	info->input_dev->id.version = 0;
107 	info->input_dev->close = sc27xx_vibra_close;
108 
109 	input_set_drvdata(info->input_dev, info);
110 	input_set_capability(info->input_dev, EV_FF, FF_RUMBLE);
111 	INIT_WORK(&info->play_work, sc27xx_vibra_play_work);
112 	info->enabled = false;
113 
114 	error = sc27xx_vibra_hw_init(info);
115 	if (error) {
116 		dev_err(&pdev->dev, "failed to initialize the vibrator.\n");
117 		return error;
118 	}
119 
120 	error = input_ff_create_memless(info->input_dev, NULL,
121 					sc27xx_vibra_play);
122 	if (error) {
123 		dev_err(&pdev->dev, "failed to register vibrator to FF.\n");
124 		return error;
125 	}
126 
127 	error = input_register_device(info->input_dev);
128 	if (error) {
129 		dev_err(&pdev->dev, "failed to register input device.\n");
130 		return error;
131 	}
132 
133 	return 0;
134 }
135 
136 static const struct of_device_id sc27xx_vibra_of_match[] = {
137 	{ .compatible = "sprd,sc2731-vibrator", },
138 	{}
139 };
140 MODULE_DEVICE_TABLE(of, sc27xx_vibra_of_match);
141 
142 static struct platform_driver sc27xx_vibra_driver = {
143 	.driver = {
144 		.name = "sc27xx-vibrator",
145 		.of_match_table = sc27xx_vibra_of_match,
146 	},
147 	.probe = sc27xx_vibra_probe,
148 };
149 
150 module_platform_driver(sc27xx_vibra_driver);
151 
152 MODULE_DESCRIPTION("Spreadtrum SC27xx Vibrator Driver");
153 MODULE_LICENSE("GPL v2");
154 MODULE_AUTHOR("Xiaotong Lu <xiaotong.lu@spreadtrum.com>");
155