Re: PCA GPIO interrupt triggers, matrix-keypad

From: Peter Rusko
Date: Mon Mar 26 2012 - 06:27:38 EST

? I fail to see why having EDGE_FALLING together with EDGE_RISING is not
supported. Are you sure you didn't use some other IRQ_TYPE here?

Yes, you're right, the problem is not there.

I think, this patch should work:

Think? Can't you test it :)
I wish that could be that simple :)

I can test it with the matrix-keypad driver. But there's an inverter
(+delay) in the circuit (to prevent contact bounce) and I don't know how
it affects the signals. But in the end sometimes I don't get e.g. the
key-release event.

Another change in the code was with the IRQ request. I could only make
the matrix-keypad driver working with threaded interrupts:

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index e2ae657..f047502 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -48,7 +48,7 @@ struct matrix_keypad {
static void __activate_col(const struct matrix_keypad_platform_data *pdata,
int col, bool on)
- bool level_on = !pdata->active_low;
+ bool level_on = (!pdata->active_low)^(!!pdata->invert_output);

if (on) {
gpio_direction_output(pdata->col_gpios[col], level_on);
@@ -341,7 +341,8 @@ static int __devinit init_matrix_gpio(struct platform_device *pdev,
} else {
for (i = 0; i < pdata->num_row_gpios; i++) {
- err = request_irq(gpio_to_irq(pdata->row_gpios[i]),
+ err = request_threaded_irq(gpio_to_irq(pdata->row_gpios[i]),

Is this okay, or is there another way?

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