kernel: change debounce logic in the gpio-buttons driver

 * thanks to Nuno Gonçalves

SVN-Revision: 19115

diff --git a/target/linux/generic-2.6/files/drivers/input/misc/gpio_buttons.c b/target/linux/generic-2.6/files/drivers/input/misc/gpio_buttons.c
index 83a8178340adc6f8404fe5a8b95c07fea88b4f94..e4e0e339d725b34b32a3905339ac0275b2a9956c 100644 (file)
--- a/target/linux/generic-2.6/files/drivers/input/misc/gpio_buttons.c
+++ b/target/linux/generic-2.6/files/drivers/input/misc/gpio_buttons.c
@@ -1,7 +1,8 @@
 /*
  *  Driver for buttons on GPIO lines not capable of generating interrupts
  *
- *  Copyright (C) 2007,2008 Gabor Juhos <juhosg at openwrt.org>
+ *  Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
+ *  Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com>
  *
  *  This file was based on: /drivers/input/misc/cobalt_btns.c
  *     Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
@@ -29,12 +30,18 @@
 #include <asm/gpio.h>
 
 #define DRV_NAME       "gpio-buttons"
-#define DRV_VERSION    "0.1.1"
+#define DRV_VERSION    "0.1.2"
 #define PFX            DRV_NAME ": "
 
+struct gpio_button_data {
+       int last_state;
+       int count;
+};
+
 struct gpio_buttons_dev {
        struct input_polled_dev *poll_dev;
        struct gpio_buttons_platform_data *pdata;
+       struct gpio_button_data *data;
 };
 
 static void gpio_buttons_poll(struct input_polled_dev *dev)
@@ -49,22 +56,18 @@ static void gpio_buttons_poll(struct input_polled_dev *dev)
                unsigned int type = button->type ?: EV_KEY;
                int state;
 
-               state = gpio_get_value(button->gpio) ? 1 : 0;
-               state ^= button->active_low;
-
-               if (state) {
-                       button->count++;
-               } else {
-                       if (button->count >= button->threshold) {
-                               input_event(input, type, button->code, 1);
-                               input_sync(input);
-                       }
-                       button->count = 0;
+               if (bdev->data[i].count < button->threshold) {
+                       bdev->data[i].count++;
+                       continue;
                }
 
-               if (button->count == button->threshold) {
-                       input_event(input, type, button->code, 0);
+               state = gpio_get_value(button->gpio) ? 1 : 0;
+               if (state != bdev->data[i].last_state) {
+                       input_event(input, type, button->code,
+                                   !!(state ^ button->active_low));
                        input_sync(input);
+                       bdev->data[i].count = 0;
+                       bdev->data[i].last_state = state;
                }
        }
 }
@@ -77,16 +80,19 @@ static int __devinit gpio_buttons_probe(struct platform_device *pdev)
        struct input_dev *input;
        int error, i;
 
-
        if (!pdata)
                return -ENXIO;
 
-       bdev = kzalloc(sizeof(*bdev), GFP_KERNEL);
+       bdev = kzalloc(sizeof(struct gpio_buttons_dev) +
+                      sizeof(struct gpio_button_data) * pdata->nbuttons,
+                      GFP_KERNEL);
        if (!bdev) {
                printk(KERN_ERR DRV_NAME "no memory for device\n");
                return -ENOMEM;
        }
 
+       bdev->data = (struct gpio_button_data *) &bdev[1];
+
        poll_dev = input_allocate_polled_device();
        if (!poll_dev) {
                printk(KERN_ERR DRV_NAME "no memory for polled device\n");
@@ -131,7 +137,7 @@ static int __devinit gpio_buttons_probe(struct platform_device *pdev)
                }
 
                input_set_capability(input, type, button->code);
-               button->count = 0;
+               bdev->data[i].last_state = gpio_get_value(button->gpio) ? 1 : 0;
        }
 
        bdev->poll_dev = poll_dev;

diff --git a/target/linux/generic-2.6/files/include/linux/gpio_buttons.h b/target/linux/generic-2.6/files/include/linux/gpio_buttons.h
index f5e62972584d5be8d2a485d37590baf1b0dc44bf..f85b993ed20ab6888de06350bcc0389904ac8c6d 100644 (file)
--- a/target/linux/generic-2.6/files/include/linux/gpio_buttons.h
+++ b/target/linux/generic-2.6/files/include/linux/gpio_buttons.h
@@ -1,7 +1,7 @@
 /*
  *  Definitions for the GPIO buttons interface driver
  *
- *  Copyright (C) 2007,2008 Gabor Juhos <juhosg at openwrt.org>
+ *  Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
  *
  *  This file was based on: /include/linux/gpio_keys.h
  *     The original gpio_keys.h seems not to have a license.
@@ -21,7 +21,6 @@ struct gpio_button {
        char    *desc;          /* button description */
        int     type;           /* input event type (EV_KEY, EV_SW) */
        int     code;           /* input event code (KEY_*, SW_*) */
-       int     count;
        int     threshold;      /* count threshold */
 };
 
@@ -32,4 +31,3 @@ struct gpio_buttons_platform_data {
 };
 
 #endif /* _GPIO_BUTTONS_H_ */
-