2 * Driver for keys on GPIO lines capable of generating interrupts.
4 * Copyright 2005 Phil Blundell
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/module.h>
12 #include <linux/version.h>
14 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/irq.h>
18 #include <linux/sched.h>
20 #include <linux/sysctl.h>
21 #include <linux/proc_fs.h>
22 #include <linux/delay.h>
23 #include <linux/platform_device.h>
24 #include <linux/input.h>
25 #include <linux/irq.h>
26 #include <linux/gpio_keys.h>
30 static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
33 struct platform_device *pdev = dev_id;
34 struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
35 struct input_dev *input = platform_get_drvdata(pdev);
37 for (i = 0; i < pdata->nbuttons; i++) {
38 struct gpio_keys_button *button = &pdata->buttons[i];
39 int gpio = button->gpio;
41 if (irq == gpio_to_irq(gpio)) {
42 unsigned int type = button->type ?: EV_KEY;
43 int state = (gpio_get_value(gpio) ? 1 : 0) ^ button->active_low;
45 input_event(input, type, button->code, !!state);
53 static int __devinit gpio_keys_probe(struct platform_device *pdev)
55 struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
56 struct input_dev *input;
59 input = input_allocate_device();
63 platform_set_drvdata(pdev, input);
65 input->evbit[0] = BIT(EV_KEY);
67 input->name = pdev->name;
68 input->phys = "gpio-keys/input0";
69 input->dev.parent = &pdev->dev;
71 input->id.bustype = BUS_HOST;
72 input->id.vendor = 0x0001;
73 input->id.product = 0x0001;
74 input->id.version = 0x0100;
76 for (i = 0; i < pdata->nbuttons; i++) {
77 struct gpio_keys_button *button = &pdata->buttons[i];
78 int irq = gpio_to_irq(button->gpio);
79 unsigned int type = button->type ?: EV_KEY;
85 "Unable to get irq number for GPIO %d,"
91 error = request_irq(irq, gpio_keys_isr,
92 IRQF_SAMPLE_RANDOM | IRQF_TRIGGER_RISING |
94 button->desc ? button->desc : "gpio_keys",
98 "gpio-keys: Unable to claim irq %d; error %d\n",
103 input_set_capability(input, type, button->code);
106 error = input_register_device(input);
109 "gpio-keys: Unable to register input device, "
110 "error: %d\n", error);
118 free_irq(gpio_to_irq(pdata->buttons[i].gpio), pdev);
120 platform_set_drvdata(pdev, NULL);
121 input_free_device(input);
126 static int __devexit gpio_keys_remove(struct platform_device *pdev)
128 struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
129 struct input_dev *input = platform_get_drvdata(pdev);
132 for (i = 0; i < pdata->nbuttons; i++) {
133 int irq = gpio_to_irq(pdata->buttons[i].gpio);
137 input_unregister_device(input);
142 struct platform_driver gpio_keys_device_driver = {
143 .probe = gpio_keys_probe,
144 .remove = __devexit_p(gpio_keys_remove),
150 static int __init gpio_keys_init(void)
152 return platform_driver_register(&gpio_keys_device_driver);
155 static void __exit gpio_keys_exit(void)
157 platform_driver_unregister(&gpio_keys_device_driver);
160 module_init(gpio_keys_init);
161 module_exit(gpio_keys_exit);
163 MODULE_LICENSE("GPL");
164 MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
165 MODULE_DESCRIPTION("Keyboard driver for CPU GPIOs");