[PATCH 1/2] Revert "Input: gpio-keys - change timer to workqueue"

Jani Nikula
2009-06-26T12:16:22Z

This reverts commit 0b346838c5862bfe911432956a106d602535d030.

This commit breaks GPIO debouncing by replacing the original mod_timer
with schedule_delayed_work in the interrupt handler. The latter does not
kick the timer further on GPIO line changes as it should to perform
debouncing.

Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com>
---
drivers/input/keyboard/gpio_keys.c | 32 ++++++++++++++++++++------------
1 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
index 2157cd7..9767213 100644
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -22,14 +22,13 @@
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/gpio_keys.h>
-#include <linux/workqueue.h>

#include <asm/gpio.h>

struct gpio_button_data {
struct gpio_keys_button *button;
struct input_dev *input;
- struct delayed_work work;
+ struct timer_list timer;
};

struct gpio_keys_drvdata {
@@ -37,10 +36,8 @@ struct gpio_keys_drvdata {
struct gpio_button_data data[0];
};

-static void gpio_keys_report_event(struct work_struct *work)
+static void gpio_keys_report_event(struct gpio_button_data *bdata)
{
- struct gpio_button_data *bdata =
- container_of(work, struct gpio_button_data, work.work);
struct gpio_keys_button *button = bdata->button;
struct input_dev *input = bdata->input;
unsigned int type = button->type ?: EV_KEY;
@@ -50,17 +47,25 @@ static void gpio_keys_report_event(struct work_struct *work)
input_sync(input);
}

+static void gpio_check_button(unsigned long _data)
+{
+ struct gpio_button_data *data = (struct gpio_button_data *)_data;
+
+ gpio_keys_report_event(data);
+}
+
static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
{
struct gpio_button_data *bdata = dev_id;
struct gpio_keys_button *button = bdata->button;
- unsigned long delay;

BUG_ON(irq != gpio_to_irq(button->gpio));

- delay = button->debounce_interval ?
- msecs_to_jiffies(button->debounce_interval) : 0;
- schedule_delayed_work(&bdata->work, delay);
+ if (button->debounce_interval)
+ mod_timer(&bdata->timer,
+ jiffies + msecs_to_jiffies(button->debounce_interval));
+ else
+ gpio_keys_report_event(bdata);

return IRQ_HANDLED;
}
@@ -107,7 +112,8 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev)

bdata->input = input;
bdata->button = button;
- INIT_DELAYED_WORK(&bdata->work, gpio_keys_report_event);
+ setup_timer(&bdata->timer,
+ gpio_check_button, (unsigned long)bdata);

error = gpio_request(button->gpio, button->desc ?: "gpio_keys");
if (error < 0) {
@@ -166,7 +172,8 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev)
fail2:
while (--i >= 0) {
free_irq(gpio_to_irq(pdata->buttons[i].gpio), &ddata->data[i]);
- cancel_delayed_work_sync(&ddata->data[i].work);
+ if (pdata->buttons[i].debounce_interval)
+ del_timer_sync(&ddata->data[i].timer);
gpio_free(pdata->buttons[i].gpio);
}

@@ -190,7 +197,8 @@ static int __devexit gpio_keys_remove(struct platform_device *pdev)
for (i = 0; i < pdata->nbuttons; i++) {
int irq = gpio_to_irq(pdata->buttons[i].gpio);
free_irq(irq, &ddata->data[i]);
- cancel_delayed_work_sync(&ddata->data[i].work);
+ if (pdata->buttons[i].debounce_interval)
+ del_timer_sync(&ddata->data[i].timer);
gpio_free(pdata->buttons[i].gpio);
}

--
1.6.3.2