145 lines
3.0 KiB
C
145 lines
3.0 KiB
C
/*
|
|
* Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
|
|
*
|
|
* Under GPLv2
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <errno.h>
|
|
#include <init.h>
|
|
#include <clock.h>
|
|
#include <gpio_keys.h>
|
|
#include <poller.h>
|
|
#include <gpio.h>
|
|
|
|
struct gpio_key {
|
|
int code;
|
|
|
|
int gpio;
|
|
int active_low;
|
|
|
|
int previous_state;
|
|
};
|
|
|
|
struct gpio_keys {
|
|
struct gpio_key *buttons;
|
|
int nbuttons;
|
|
|
|
/* optional */
|
|
int fifo_size;
|
|
|
|
struct kfifo *recv_fifo;
|
|
struct poller_struct poller;
|
|
struct console_device cdev;
|
|
};
|
|
|
|
static inline struct gpio_keys *
|
|
poller_to_gk_pdata(struct poller_struct *poller)
|
|
{
|
|
return container_of(poller, struct gpio_keys, poller);
|
|
}
|
|
|
|
static inline struct gpio_keys *
|
|
cdev_to_gk_pdata(struct console_device *cdev)
|
|
{
|
|
return container_of(cdev, struct gpio_keys, cdev);
|
|
}
|
|
|
|
static void gpio_key_poller(struct poller_struct *poller)
|
|
{
|
|
struct gpio_keys *gk = poller_to_gk_pdata(poller);
|
|
struct gpio_key *gb;
|
|
int i, val;
|
|
|
|
for (i = 0; i < gk->nbuttons; i++) {
|
|
|
|
gb = &gk->buttons[i];
|
|
val = gpio_get_value(gb->gpio);
|
|
|
|
if (val != gb->previous_state && val != gb->active_low) {
|
|
kfifo_put(gk->recv_fifo, (u_char*)&gb->code, sizeof(int));
|
|
debug("pressed gpio(%d) as %d\n", gb->gpio, gb->code);
|
|
}
|
|
gb->previous_state = val;
|
|
}
|
|
}
|
|
|
|
static int gpio_keys_tstc(struct console_device *cdev)
|
|
{
|
|
struct gpio_keys *gk = cdev_to_gk_pdata(cdev);
|
|
|
|
return (kfifo_len(gk->recv_fifo) == 0) ? 0 : 1;
|
|
}
|
|
|
|
static int gpio_keys_getc(struct console_device *cdev)
|
|
{
|
|
int code = 0;
|
|
struct gpio_keys *gk = cdev_to_gk_pdata(cdev);
|
|
|
|
kfifo_get(gk->recv_fifo, (u_char*)&code, sizeof(int));
|
|
return code;
|
|
}
|
|
|
|
static int __init gpio_keys_probe(struct device_d *dev)
|
|
{
|
|
int ret, i, gpio;
|
|
struct gpio_keys_platform_data *pdata;
|
|
struct console_device *cdev;
|
|
struct gpio_keys *gk;
|
|
|
|
pdata = dev->platform_data;
|
|
|
|
if (!pdata) {
|
|
/* small (so we copy it) but critical! */
|
|
pr_err("missing platform_data\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
gk = xzalloc(sizeof(*gk));
|
|
|
|
gk->fifo_size = 50;
|
|
|
|
if (pdata->fifo_size)
|
|
gk->fifo_size = pdata->fifo_size;
|
|
|
|
gk->recv_fifo = kfifo_alloc(pdata->fifo_size);
|
|
|
|
gk->buttons = xzalloc(pdata->nbuttons * sizeof(*gk->buttons));
|
|
gk->nbuttons = pdata->nbuttons;
|
|
|
|
for (i = 0; i < gk->nbuttons; i++) {
|
|
gk->buttons[i].gpio = pdata->buttons[i].gpio;
|
|
gk->buttons[i].code = pdata->buttons[i].code;
|
|
gk->buttons[i].active_low = pdata->buttons[i].active_low;
|
|
}
|
|
|
|
for (i = 0; i < pdata->nbuttons; i++) {
|
|
gpio = gk->buttons[i].gpio;
|
|
ret = gpio_request(gpio, "gpio_keys");
|
|
if (ret) {
|
|
pr_err("gpio_keys: (%d) can not be requested\n", gpio);
|
|
return ret;
|
|
}
|
|
gpio_direction_input(gpio);
|
|
gk->buttons[i].previous_state = gk->buttons[i].active_low;
|
|
}
|
|
|
|
gk->poller.func = gpio_key_poller;
|
|
|
|
cdev = &gk->cdev;
|
|
dev->type_data = cdev;
|
|
cdev->dev = dev;
|
|
cdev->tstc = gpio_keys_tstc;
|
|
cdev->getc = gpio_keys_getc;
|
|
|
|
console_register(&gk->cdev);
|
|
|
|
return poller_register(&gk->poller);
|
|
}
|
|
|
|
static struct driver_d gpio_keys_driver = {
|
|
.name = "gpio_keys",
|
|
.probe = gpio_keys_probe,
|
|
};
|
|
device_platform_driver(gpio_keys_driver);
|