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
27struct tps65218_pwrbutton {
28	struct device *dev;
29	struct tps65218 *tps;
30	struct input_dev *idev;
31};
32
33static 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
54out:
55	return IRQ_HANDLED;
56}
57
58static 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
109static const struct of_device_id of_tps65218_pwr_match[] = {
110	{ .compatible = "ti,tps65218-pwrbutton" },
111	{ },
112};
113MODULE_DEVICE_TABLE(of, of_tps65218_pwr_match);
114
115static 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};
122module_platform_driver(tps65218_pwron_driver);
123
124MODULE_DESCRIPTION("TPS65218 Power Button");
125MODULE_LICENSE("GPL v2");
126MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
127