xref: /openbmc/linux/drivers/input/misc/e3x0-button.c (revision e2c75e76)
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 
25 static 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 
35 static 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 
46 static 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 
56 static 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 
66 static SIMPLE_DEV_PM_OPS(e3x0_button_pm_ops,
67 			 e3x0_button_suspend, e3x0_button_resume);
68 
69 static 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 	device_init_wakeup(&pdev->dev, 1);
124 	return 0;
125 }
126 
127 #ifdef CONFIG_OF
128 static const struct of_device_id e3x0_button_match[] = {
129 	{ .compatible = "ettus,e3x0-button", },
130 	{ }
131 };
132 MODULE_DEVICE_TABLE(of, e3x0_button_match);
133 #endif
134 
135 static struct platform_driver e3x0_button_driver = {
136 	.driver		= {
137 		.name	= "e3x0-button",
138 		.of_match_table = of_match_ptr(e3x0_button_match),
139 		.pm	= &e3x0_button_pm_ops,
140 	},
141 	.probe		= e3x0_button_probe,
142 };
143 
144 module_platform_driver(e3x0_button_driver);
145 
146 MODULE_LICENSE("GPL v2");
147 MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>");
148 MODULE_DESCRIPTION("NI Ettus Research USRP E3x0 Button driver");
149 MODULE_ALIAS("platform:e3x0-button");
150