1 /*
2  * Texas Instruments' 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  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12  * kind, whether express or implied; without even the implied warranty
13  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/init.h>
18 #include <linux/input.h>
19 #include <linux/interrupt.h>
20 #include <linux/kernel.h>
21 #include <linux/mfd/tps65218.h>
22 #include <linux/module.h>
23 #include <linux/of.h>
24 #include <linux/platform_device.h>
25 #include <linux/slab.h>
26 
27 struct tps65218_pwrbutton {
28 	struct device *dev;
29 	struct tps65218 *tps;
30 	struct input_dev *idev;
31 };
32 
33 static irqreturn_t tps65218_pwr_irq(int irq, void *_pwr)
34 {
35 	struct tps65218_pwrbutton *pwr = _pwr;
36 	unsigned int reg;
37 	int error;
38 
39 	error = tps65218_reg_read(pwr->tps, TPS65218_REG_STATUS, &reg);
40 	if (error) {
41 		dev_err(pwr->dev, "can't read register: %d\n", error);
42 		goto out;
43 	}
44 
45 	if (reg & TPS65218_STATUS_PB_STATE) {
46 		input_report_key(pwr->idev, KEY_POWER, 1);
47 		pm_wakeup_event(pwr->dev, 0);
48 	} else {
49 		input_report_key(pwr->idev, KEY_POWER, 0);
50 	}
51 
52 	input_sync(pwr->idev);
53 
54 out:
55 	return IRQ_HANDLED;
56 }
57 
58 static int tps65218_pwron_probe(struct platform_device *pdev)
59 {
60 	struct tps65218 *tps = dev_get_drvdata(pdev->dev.parent);
61 	struct device *dev = &pdev->dev;
62 	struct tps65218_pwrbutton *pwr;
63 	struct input_dev *idev;
64 	int error;
65 	int irq;
66 
67 	pwr = devm_kzalloc(dev, sizeof(*pwr), GFP_KERNEL);
68 	if (!pwr)
69 		return -ENOMEM;
70 
71 	idev = devm_input_allocate_device(dev);
72 	if (!idev)
73 		return -ENOMEM;
74 
75 	idev->name = "tps65218_pwrbutton";
76 	idev->phys = "tps65218_pwrbutton/input0";
77 	idev->dev.parent = dev;
78 	idev->id.bustype = BUS_I2C;
79 
80 	input_set_capability(idev, EV_KEY, KEY_POWER);
81 
82 	pwr->tps = tps;
83 	pwr->dev = dev;
84 	pwr->idev = idev;
85 	platform_set_drvdata(pdev, pwr);
86 	device_init_wakeup(dev, true);
87 
88 	irq = platform_get_irq(pdev, 0);
89 	error = devm_request_threaded_irq(dev, irq, NULL, tps65218_pwr_irq,
90 					  IRQF_TRIGGER_RISING |
91 						IRQF_TRIGGER_FALLING |
92 						IRQF_ONESHOT,
93 					  "tps65218-pwrbutton", pwr);
94 	if (error) {
95 		dev_err(dev, "failed to request IRQ #%d: %d\n",
96 			irq, error);
97 		return error;
98 	}
99 
100 	error= input_register_device(idev);
101 	if (error) {
102 		dev_err(dev, "Can't register power button: %d\n", error);
103 		return error;
104 	}
105 
106 	return 0;
107 }
108 
109 static const struct of_device_id of_tps65218_pwr_match[] = {
110 	{ .compatible = "ti,tps65218-pwrbutton" },
111 	{ },
112 };
113 MODULE_DEVICE_TABLE(of, of_tps65218_pwr_match);
114 
115 static struct platform_driver tps65218_pwron_driver = {
116 	.probe	= tps65218_pwron_probe,
117 	.driver	= {
118 		.name	= "tps65218_pwrbutton",
119 		.of_match_table = of_tps65218_pwr_match,
120 	},
121 };
122 module_platform_driver(tps65218_pwron_driver);
123 
124 MODULE_DESCRIPTION("TPS65218 Power Button");
125 MODULE_LICENSE("GPL v2");
126 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
127