1/*
2 * Copyright (c) 2014, National Instruments Corp. All rights reserved.
3 *
4 * Driver for NI Ettus Research USRP E3x0 Button Driver
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 of the License.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/device.h>
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/platform_device.h>
20#include <linux/input.h>
21#include <linux/interrupt.h>
22#include <linux/of.h>
23#include <linux/slab.h>
24
25static irqreturn_t e3x0_button_release_handler(int irq, void *data)
26{
27	struct input_dev *idev = data;
28
29	input_report_key(idev, KEY_POWER, 0);
30	input_sync(idev);
31
32	return IRQ_HANDLED;
33}
34
35static irqreturn_t e3x0_button_press_handler(int irq, void *data)
36{
37	struct input_dev *idev = data;
38
39	input_report_key(idev, KEY_POWER, 1);
40	pm_wakeup_event(idev->dev.parent, 0);
41	input_sync(idev);
42
43	return IRQ_HANDLED;
44}
45
46static int __maybe_unused e3x0_button_suspend(struct device *dev)
47{
48	struct platform_device *pdev = to_platform_device(dev);
49
50	if (device_may_wakeup(dev))
51		enable_irq_wake(platform_get_irq_byname(pdev, "press"));
52
53	return 0;
54}
55
56static int __maybe_unused e3x0_button_resume(struct device *dev)
57{
58	struct platform_device *pdev = to_platform_device(dev);
59
60	if (device_may_wakeup(dev))
61		disable_irq_wake(platform_get_irq_byname(pdev, "press"));
62
63	return 0;
64}
65
66static SIMPLE_DEV_PM_OPS(e3x0_button_pm_ops,
67			 e3x0_button_suspend, e3x0_button_resume);
68
69static int e3x0_button_probe(struct platform_device *pdev)
70{
71	struct input_dev *input;
72	int irq_press, irq_release;
73	int error;
74
75	irq_press = platform_get_irq_byname(pdev, "press");
76	if (irq_press < 0) {
77		dev_err(&pdev->dev, "No IRQ for 'press', error=%d\n",
78			irq_press);
79		return irq_press;
80	}
81
82	irq_release = platform_get_irq_byname(pdev, "release");
83	if (irq_release < 0) {
84		dev_err(&pdev->dev, "No IRQ for 'release', error=%d\n",
85			irq_release);
86		return irq_release;
87	}
88
89	input = devm_input_allocate_device(&pdev->dev);
90	if (!input)
91		return -ENOMEM;
92
93	input->name = "NI Ettus Research USRP E3x0 Button Driver";
94	input->phys = "e3x0_button/input0";
95	input->dev.parent = &pdev->dev;
96
97	input_set_capability(input, EV_KEY, KEY_POWER);
98
99	error = devm_request_irq(&pdev->dev, irq_press,
100				 e3x0_button_press_handler, 0,
101				 "e3x0-button", input);
102	if (error) {
103		dev_err(&pdev->dev, "Failed to request 'press' IRQ#%d: %d\n",
104			irq_press, error);
105		return error;
106	}
107
108	error = devm_request_irq(&pdev->dev, irq_release,
109				 e3x0_button_release_handler, 0,
110				 "e3x0-button", input);
111	if (error) {
112		dev_err(&pdev->dev, "Failed to request 'release' IRQ#%d: %d\n",
113			irq_release, error);
114		return error;
115	}
116
117	error = input_register_device(input);
118	if (error) {
119		dev_err(&pdev->dev, "Can't register input device: %d\n", error);
120		return error;
121	}
122
123	platform_set_drvdata(pdev, input);
124	device_init_wakeup(&pdev->dev, 1);
125	return 0;
126}
127
128static int e3x0_button_remove(struct platform_device *pdev)
129{
130	device_init_wakeup(&pdev->dev, 0);
131	return 0;
132}
133
134#ifdef CONFIG_OF
135static const struct of_device_id e3x0_button_match[] = {
136	{ .compatible = "ettus,e3x0-button", },
137	{ }
138};
139MODULE_DEVICE_TABLE(of, e3x0_button_match);
140#endif
141
142static struct platform_driver e3x0_button_driver = {
143	.driver		= {
144		.name	= "e3x0-button",
145		.of_match_table = of_match_ptr(e3x0_button_match),
146		.pm	= &e3x0_button_pm_ops,
147	},
148	.probe		= e3x0_button_probe,
149	.remove		= e3x0_button_remove,
150};
151
152module_platform_driver(e3x0_button_driver);
153
154MODULE_LICENSE("GPL v2");
155MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>");
156MODULE_DESCRIPTION("NI Ettus Research USRP E3x0 Button driver");
157MODULE_ALIAS("platform:e3x0-button");
158