- 根目录:
- drivers
- input
- misc
- gpio_event.c
/* drivers/input/misc/gpio_event.c
*
* Copyright (C) 2007 Google, Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/module.h>
#include <linux/input.h>
#include <linux/gpio_event.h>
#include <linux/hrtimer.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
struct gpio_event {
struct gpio_event_input_devs *input_devs;
const struct gpio_event_platform_data *info;
void *state[0];
};
static int gpio_input_event(
struct input_dev *dev, unsigned int type, unsigned int code, int value)
{
int i;
int devnr;
int ret = 0;
int tmp_ret;
struct gpio_event_info **ii;
struct gpio_event *ip = input_get_drvdata(dev);
for (devnr = 0; devnr < ip->input_devs->count; devnr++)
if (ip->input_devs->dev[devnr] == dev)
break;
if (devnr == ip->input_devs->count) {
pr_err("gpio_input_event: unknown device %p\n", dev);
return -EIO;
}
for (i = 0, ii = ip->info->info; i < ip->info->info_count; i++, ii++) {
if ((*ii)->event) {
tmp_ret = (*ii)->event(ip->input_devs, *ii,
&ip->state[i],
devnr, type, code, value);
if (tmp_ret)
ret = tmp_ret;
}
}
return ret;
}
static int gpio_event_call_all_func(struct gpio_event *ip, int func)
{
int i;
int ret;
struct gpio_event_info **ii;
if (func == GPIO_EVENT_FUNC_INIT || func == GPIO_EVENT_FUNC_RESUME) {
ii = ip->info->info;
for (i = 0; i < ip->info->info_count; i++, ii++) {
if ((*ii)->func == NULL) {
ret = -ENODEV;
pr_err("gpio_event_probe: Incomplete pdata, "
"no function\n");
goto err_no_func;
}
if (func == GPIO_EVENT_FUNC_RESUME && (*ii)->no_suspend)
continue;
ret = (*ii)->func(ip->input_devs, *ii, &ip->state[i],
func);
if (ret) {
pr_err("gpio_event_probe: function failed\n");
goto err_func_failed;
}
}
return 0;
}
ret = 0;
i = ip->info->info_count;
ii = ip->info->info + i;
while (i > 0) {
i--;
ii--;
if ((func & ~1) == GPIO_EVENT_FUNC_SUSPEND && (*ii)->no_suspend)
continue;
(*ii)->func(ip->input_devs, *ii, &ip->state[i], func & ~1);
err_func_failed:
err_no_func:
;
}
return ret;
}
static void __maybe_unused gpio_event_suspend(struct gpio_event *ip)
{
gpio_event_call_all_func(ip, GPIO_EVENT_FUNC_SUSPEND);
if (ip->info->power)
ip->info->power(ip->info, 0);
}
static void __maybe_unused gpio_event_resume(struct gpio_event *ip)
{
if (ip->info->power)
ip->info->power(ip->info, 1);
gpio_event_call_all_func(ip, GPIO_EVENT_FUNC_RESUME);
}
static int gpio_event_probe(struct platform_device *pdev)
{
int err;
struct gpio_event *ip;
struct gpio_event_platform_data *event_info;
int dev_count = 1;
int i;
int registered = 0;
event_info = pdev->dev.platform_data;
if (event_info == NULL) {
pr_err("gpio_event_probe: No pdata\n");
return -ENODEV;
}
if ((!event_info->name && !event_info->names[0]) ||
!event_info->info || !event_info->info_count) {
pr_err("gpio_event_probe: Incomplete pdata\n");
return -ENODEV;
}
if (!event_info->name)
while (event_info->names[dev_count])
dev_count++;
ip = kzalloc(sizeof(*ip) +
sizeof(ip->state[0]) * event_info->info_count +
sizeof(*ip->input_devs) +
sizeof(ip->input_devs->dev[0]) * dev_count, GFP_KERNEL);
if (ip == NULL) {
err = -ENOMEM;
pr_err("gpio_event_probe: Failed to allocate private data\n");
goto err_kp_alloc_failed;
}
ip->input_devs = (void*)&ip->state[event_info->info_count];
platform_set_drvdata(pdev, ip);
for (i = 0; i < dev_count; i++) {
struct input_dev *input_dev = input_allocate_device();
if (input_dev == NULL) {
err = -ENOMEM;
pr_err("gpio_event_probe: "
"Failed to allocate input device\n");
goto err_input_dev_alloc_failed;
}
input_set_drvdata(input_dev, ip);
input_dev->name = event_info->name ?
event_info->name : event_info->names[i];
input_dev->event = gpio_input_event;
ip->input_devs->dev[i] = input_dev;
}
ip->input_devs->count = dev_count;
ip->info = event_info;
if (event_info->power)
ip->info->power(ip->info, 1);
err = gpio_event_call_all_func(ip, GPIO_EVENT_FUNC_INIT);
if (err)
goto err_call_all_func_failed;
for (i = 0; i < dev_count; i++) {
err = input_register_device(ip->input_devs->dev[i]);
if (err) {
pr_err("gpio_event_probe: Unable to register %s "
"input device\n", ip->input_devs->dev[i]->name);
goto err_input_register_device_failed;
}
registered++;
}
return 0;
err_input_register_device_failed:
gpio_event_call_all_func(ip, GPIO_EVENT_FUNC_UNINIT);
err_call_all_func_failed:
if (event_info->power)
ip->info->power(ip->info, 0);
for (i = 0; i < registered; i++)
input_unregister_device(ip->input_devs->dev[i]);
for (i = dev_count - 1; i >= registered; i--) {
input_free_device(ip->input_devs->dev[i]);
err_input_dev_alloc_failed:
;
}
kfree(ip);
err_kp_alloc_failed:
return err;
}
static int gpio_event_remove(struct platform_device *pdev)
{
struct gpio_event *ip = platform_get_drvdata(pdev);
int i;
gpio_event_call_all_func(ip, GPIO_EVENT_FUNC_UNINIT);
if (ip->info->power)
ip->info->power(ip->info, 0);
for (i = 0; i < ip->input_devs->count; i++)
input_unregister_device(ip->input_devs->dev[i]);
kfree(ip);
return 0;
}
static struct platform_driver gpio_event_driver = {
.probe = gpio_event_probe,
.remove = gpio_event_remove,
.driver = {
.name = GPIO_EVENT_DEV_NAME,
},
};
static int __devinit gpio_event_init(void)
{
return platform_driver_register(&gpio_event_driver);
}
static void __exit gpio_event_exit(void)
{
platform_driver_unregister(&gpio_event_driver);
}
module_init(gpio_event_init);
module_exit(gpio_event_exit);
MODULE_DESCRIPTION("GPIO Event Driver");
MODULE_LICENSE("GPL");