1 /*
2  * Texas Instruments' TPS65217 and TPS65218 Power Button Input Driver
3  *
4  * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com/
5  * Author: Felipe Balbi <balbi@ti.com>
6  * Author: Marcin Niestroj <m.niestroj@grinn-global.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
13  * kind, whether express or implied; without even the implied warranty
14  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  */
17 
18 #include <linux/init.h>
19 #include <linux/input.h>
20 #include <linux/interrupt.h>
21 #include <linux/kernel.h>
22 #include <linux/mfd/tps65217.h>
23 #include <linux/mfd/tps65218.h>
24 #include <linux/module.h>
25 #include <linux/of.h>
26 #include <linux/platform_device.h>
27 #include <linux/regmap.h>
28 #include <linux/slab.h>
29 
30 struct tps6521x_data {
31 	unsigned int reg_status;
32 	unsigned int pb_mask;
33 	const char *name;
34 };
35 
36 static const struct tps6521x_data tps65217_data = {
37 	.reg_status = TPS65217_REG_STATUS,
38 	.pb_mask = TPS65217_STATUS_PB,
39 	.name = "tps65217_pwrbutton",
40 };
41 
42 static const struct tps6521x_data tps65218_data = {
43 	.reg_status = TPS65218_REG_STATUS,
44 	.pb_mask = TPS65218_STATUS_PB_STATE,
45 	.name = "tps65218_pwrbutton",
46 };
47 
48 struct tps6521x_pwrbutton {
49 	struct device *dev;
50 	struct regmap *regmap;
51 	struct input_dev *idev;
52 	const struct tps6521x_data *data;
53 	char phys[32];
54 };
55 
56 static const struct of_device_id of_tps6521x_pb_match[] = {
57 	{ .compatible = "ti,tps65217-pwrbutton", .data = &tps65217_data },
58 	{ .compatible = "ti,tps65218-pwrbutton", .data = &tps65218_data },
59 	{ },
60 };
61 MODULE_DEVICE_TABLE(of, of_tps6521x_pb_match);
62 
tps6521x_pb_irq(int irq,void * _pwr)63 static irqreturn_t tps6521x_pb_irq(int irq, void *_pwr)
64 {
65 	struct tps6521x_pwrbutton *pwr = _pwr;
66 	const struct tps6521x_data *tps_data = pwr->data;
67 	unsigned int reg;
68 	int error;
69 
70 	error = regmap_read(pwr->regmap, tps_data->reg_status, &reg);
71 	if (error) {
72 		dev_err(pwr->dev, "can't read register: %d\n", error);
73 		goto out;
74 	}
75 
76 	if (reg & tps_data->pb_mask) {
77 		input_report_key(pwr->idev, KEY_POWER, 1);
78 		pm_wakeup_event(pwr->dev, 0);
79 	} else {
80 		input_report_key(pwr->idev, KEY_POWER, 0);
81 	}
82 
83 	input_sync(pwr->idev);
84 
85 out:
86 	return IRQ_HANDLED;
87 }
88 
tps6521x_pb_probe(struct platform_device * pdev)89 static int tps6521x_pb_probe(struct platform_device *pdev)
90 {
91 	struct device *dev = &pdev->dev;
92 	struct tps6521x_pwrbutton *pwr;
93 	struct input_dev *idev;
94 	const struct of_device_id *match;
95 	int error;
96 	int irq;
97 
98 	match = of_match_node(of_tps6521x_pb_match, dev->of_node);
99 	if (!match)
100 		return -ENXIO;
101 
102 	pwr = devm_kzalloc(dev, sizeof(*pwr), GFP_KERNEL);
103 	if (!pwr)
104 		return -ENOMEM;
105 
106 	pwr->data = match->data;
107 
108 	idev = devm_input_allocate_device(dev);
109 	if (!idev)
110 		return -ENOMEM;
111 
112 	idev->name = pwr->data->name;
113 	snprintf(pwr->phys, sizeof(pwr->phys), "%s/input0",
114 		pwr->data->name);
115 	idev->phys = pwr->phys;
116 	idev->dev.parent = dev;
117 	idev->id.bustype = BUS_I2C;
118 
119 	input_set_capability(idev, EV_KEY, KEY_POWER);
120 
121 	pwr->regmap = dev_get_regmap(dev->parent, NULL);
122 	pwr->dev = dev;
123 	pwr->idev = idev;
124 	device_init_wakeup(dev, true);
125 
126 	irq = platform_get_irq(pdev, 0);
127 	if (irq < 0)
128 		return -EINVAL;
129 
130 	error = devm_request_threaded_irq(dev, irq, NULL, tps6521x_pb_irq,
131 					  IRQF_TRIGGER_RISING |
132 						IRQF_TRIGGER_FALLING |
133 						IRQF_ONESHOT,
134 					  pwr->data->name, pwr);
135 	if (error) {
136 		dev_err(dev, "failed to request IRQ #%d: %d\n", irq, error);
137 		return error;
138 	}
139 
140 	error= input_register_device(idev);
141 	if (error) {
142 		dev_err(dev, "Can't register power button: %d\n", error);
143 		return error;
144 	}
145 
146 	return 0;
147 }
148 
149 static const struct platform_device_id tps6521x_pwrbtn_id_table[] = {
150 	{ "tps65218-pwrbutton", },
151 	{ "tps65217-pwrbutton", },
152 	{ /* sentinel */ }
153 };
154 MODULE_DEVICE_TABLE(platform, tps6521x_pwrbtn_id_table);
155 
156 static struct platform_driver tps6521x_pb_driver = {
157 	.probe	= tps6521x_pb_probe,
158 	.driver	= {
159 		.name	= "tps6521x_pwrbutton",
160 		.of_match_table = of_tps6521x_pb_match,
161 	},
162 	.id_table = tps6521x_pwrbtn_id_table,
163 };
164 module_platform_driver(tps6521x_pb_driver);
165 
166 MODULE_DESCRIPTION("TPS6521X Power Button");
167 MODULE_LICENSE("GPL v2");
168 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
169