Input: matrix_keypad - force switch rows to input mode

[PATCH] Input: matrix_keypad - force switch rows to input mode

Posted by Siarhei Volkau 3 years, 5 months ago

Some Pin/GPIO controllers can't get current GPIO status when interrupt
mode is set. Specifically Ingenic's JZ4755 always returns status at the
moment of interrupt.

The patch tries to fix that by forcibly setting pin mode to GPIO input
prior to reading actual row status. enable_row_irqs seems to set
interrupt mode back as it should be.

Signed-off-by: Siarhei Volkau <lis8215@gmail.com>
---
 drivers/input/keyboard/matrix_keypad.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index 7dd3f3eda..b4c0325bb 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -127,6 +127,9 @@ static void matrix_keypad_scan(struct work_struct *work)
 
 	memset(new_state, 0, sizeof(new_state));
 
+	for (row = 0; row < pdata->num_row_gpios; row++)
+		gpio_direction_input(pdata->row_gpios[row]);
+
 	/* assert each column and read the row status out */
 	for (col = 0; col < pdata->num_col_gpios; col++) {
 
-- 
2.36.1

Re: [PATCH] Input: matrix_keypad - force switch rows to input mode

Posted by Dmitry Torokhov 3 years, 5 months ago

On Wed, Nov 02, 2022 at 07:57:47PM +0300, Siarhei Volkau wrote:
> Some Pin/GPIO controllers can't get current GPIO status when interrupt
> mode is set. Specifically Ingenic's JZ4755 always returns status at the
> moment of interrupt.
> 
> The patch tries to fix that by forcibly setting pin mode to GPIO input
> prior to reading actual row status. enable_row_irqs seems to set
> interrupt mode back as it should be.
> 
> Signed-off-by: Siarhei Volkau <lis8215@gmail.com>

Applied, thank you.

-- 
Dmitry