From: Michael Gernoth <michael@gernoth.net>
Date: Fri, 19 Aug 2011 11:53:35 +0000 (+0200)
Subject: enable hardware debouncing of keyboard gpios
X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/ms2-fixes/commitdiff_plain/62a453fc35f121dfb1a5fdf6123f320dbbede629?ds=sidebyside

enable hardware debouncing of keyboard gpios
---

diff --git a/MS2Debounce/assets/debounce.ko b/MS2Debounce/assets/debounce.ko
index 26b9824..456f4c1 100644
Binary files a/MS2Debounce/assets/debounce.ko and b/MS2Debounce/assets/debounce.ko differ
diff --git a/debounce.c b/debounce.c
index f2793a4..46c0a63 100644
--- a/debounce.c
+++ b/debounce.c
@@ -2,6 +2,10 @@
 #include <linux/device.h>
 #include <linux/platform_device.h>
 #include <linux/gpio_event.h>
+#include <mach/gpio.h>
+
+/* hardware debounce: (value + 1) * 31us */
+#define GPIO_DEBOUNCE_TIME              10240
 
 #define PREFIX "debounce: "
 
@@ -333,6 +337,28 @@ static struct device debounce_device = {
 	.release = debounce_release,
 };
 
+static unsigned int mapphone_col_gpios[] = { 43, 53, 54, 55, 56, 57, 58, 63 };
+static unsigned int mapphone_row_gpios[] = { 34, 35, 36, 37, 38, 39, 40, 41 };
+
+static void hw_debounce_pin(int gpio, int enable) {
+	printk(KERN_INFO PREFIX "%sabling hardware debounce for GPIO %d\n", (enable?"En":"Dis"), gpio);
+	if (enable)
+		omap_set_gpio_debounce_time(gpio, GPIO_DEBOUNCE_TIME);
+	omap_set_gpio_debounce(gpio, enable);
+}
+
+static void hw_debounce(int enable) {
+	int i;
+
+	for (i = 0; i < (sizeof(mapphone_col_gpios) / sizeof(mapphone_col_gpios[0])); i++) {
+		hw_debounce_pin(mapphone_col_gpios[i], enable);
+	}
+
+	for (i = 0; i < (sizeof(mapphone_row_gpios) / sizeof(mapphone_row_gpios[0])); i++) {
+		hw_debounce_pin(mapphone_row_gpios[i], enable);
+	}
+}
+
 static int __init debounce_init(void)
 {
 	struct device *event_dev = NULL;
@@ -359,6 +385,8 @@ static int __init debounce_init(void)
 		return err;
 	}
 
+	hw_debounce(1);
+
 	err = device_create_file(&debounce_device, &dev_attr_debounce_delay);
 	err = device_create_file(&debounce_device, &dev_attr_settle_time);
 	err = device_create_file(&debounce_device, &dev_attr_poll_time);
@@ -402,6 +430,7 @@ static void __exit debounce_exit(void)
 		gpio_evmi->settle_time = old_settle_time;
 		gpio_evmi->poll_time = old_poll_time;
 	}
+	hw_debounce(0);
 	device_remove_file(&debounce_device, &dev_attr_debounce_delay);
 	device_remove_file(&debounce_device, &dev_attr_settle_time);
 	device_remove_file(&debounce_device, &dev_attr_poll_time);