linux/drivers/input/keyboard/gpio_keys.c

150 lines
3.5 KiB
C

/*
* Driver for keys on GPIO lines capable of generating interrupts.
*
* Copyright 2005 Phil Blundell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/version.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/sched.h>
#include <linux/pm.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/gpio_keys.h>
#include <asm/gpio.h>
static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
{
int i;
struct platform_device *pdev = dev_id;
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
struct input_dev *input = platform_get_drvdata(pdev);
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button *button = &pdata->buttons[i];
int gpio = button->gpio;
if (irq == gpio_to_irq(gpio)) {
unsigned int type = button->type ?: EV_KEY;
int state = (gpio_get_value(gpio) ? 1 : 0) ^ button->active_low;
input_event(input, type, button->code, !!state);
input_sync(input);
}
}
return IRQ_HANDLED;
}
static int __devinit gpio_keys_probe(struct platform_device *pdev)
{
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
struct input_dev *input;
int i, error;
input = input_allocate_device();
if (!input)
return -ENOMEM;
platform_set_drvdata(pdev, input);
input->evbit[0] = BIT(EV_KEY);
input->name = pdev->name;
input->phys = "gpio-keys/input0";
input->dev.parent = &pdev->dev;
input->id.bustype = BUS_HOST;
input->id.vendor = 0x0001;
input->id.product = 0x0001;
input->id.version = 0x0100;
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button *button = &pdata->buttons[i];
int irq = gpio_to_irq(button->gpio);
unsigned int type = button->type ?: EV_KEY;
set_irq_type(irq, IRQ_TYPE_EDGE_BOTH);
error = request_irq(irq, gpio_keys_isr, IRQF_SAMPLE_RANDOM,
button->desc ? button->desc : "gpio_keys",
pdev);
if (error) {
printk(KERN_ERR "gpio-keys: unable to claim irq %d; error %d\n",
irq, error);
goto fail;
}
input_set_capability(input, type, button->code);
}
error = input_register_device(input);
if (error) {
printk(KERN_ERR "Unable to register gpio-keys input device\n");
goto fail;
}
return 0;
fail:
for (i = i - 1; i >= 0; i--)
free_irq(gpio_to_irq(pdata->buttons[i].gpio), pdev);
input_free_device(input);
return error;
}
static int __devexit gpio_keys_remove(struct platform_device *pdev)
{
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
struct input_dev *input = platform_get_drvdata(pdev);
int i;
for (i = 0; i < pdata->nbuttons; i++) {
int irq = gpio_to_irq(pdata->buttons[i].gpio);
free_irq(irq, pdev);
}
input_unregister_device(input);
return 0;
}
struct platform_driver gpio_keys_device_driver = {
.probe = gpio_keys_probe,
.remove = __devexit_p(gpio_keys_remove),
.driver = {
.name = "gpio-keys",
}
};
static int __init gpio_keys_init(void)
{
return platform_driver_register(&gpio_keys_device_driver);
}
static void __exit gpio_keys_exit(void)
{
platform_driver_unregister(&gpio_keys_device_driver);
}
module_init(gpio_keys_init);
module_exit(gpio_keys_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
MODULE_DESCRIPTION("Keyboard driver for CPU GPIOs");