[PATCH v5 6/7] Input: matrix_keypad - add settle time after enable all columns

Markus Burri posted 7 patches 2 months ago
There is a newer version of this series
[PATCH v5 6/7] Input: matrix_keypad - add settle time after enable all columns
Posted by Markus Burri 2 months ago
Matrix_keypad with high capacity need a longer settle time after enable
all columns and re-enabling interrupts.
This to give time stable the system and not generate interrupts.

Add a new optional device-tree property to configure the time before
enabling interrupts after disable all columns.
The default is no delay.

Signed-off-by: Markus Burri <markus.burri@mt.com>

---
 drivers/input/keyboard/matrix_keypad.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index 90148d3..fdb3499 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -26,6 +26,7 @@ struct matrix_keypad {
 	unsigned int row_shift;
 
 	unsigned int col_scan_delay_us;
+	unsigned int all_cols_on_delay_us;
 	/* key debounce interval in milli-second */
 	unsigned int debounce_ms;
 	bool drive_inactive_cols;
@@ -77,6 +78,9 @@ static void activate_all_cols(struct matrix_keypad *keypad, bool on)
 
 	for (col = 0; col < keypad->num_col_gpios; col++)
 		__activate_col(keypad, col, on);
+
+	if (on && keypad->all_cols_on_delay_us)
+		fsleep(keypad->all_cols_on_delay_us);
 }
 
 static bool row_asserted(struct matrix_keypad *keypad, int row)
@@ -400,6 +404,8 @@ static int matrix_keypad_probe(struct platform_device *pdev)
 				 &keypad->debounce_ms);
 	device_property_read_u32(&pdev->dev, "col-scan-delay-us",
 				 &keypad->col_scan_delay_us);
+	device_property_read_u32(&pdev->dev, "all-cols-on-delay-us",
+				 &keypad->all_cols_on_delay_us);
 
 	err = matrix_keypad_init_gpio(pdev, keypad);
 	if (err)
-- 
2.39.5
Re: [PATCH v5 6/7] Input: matrix_keypad - add settle time after enable all columns
Posted by Dmitry Torokhov 2 weeks, 2 days ago
On Fri, Jan 10, 2025 at 06:49:05AM +0100, Markus Burri wrote:
> Matrix_keypad with high capacity need a longer settle time after enable
> all columns and re-enabling interrupts.
> This to give time stable the system and not generate interrupts.
> 
> Add a new optional device-tree property to configure the time before
> enabling interrupts after disable all columns.
> The default is no delay.
> 
> Signed-off-by: Markus Burri <markus.burri@mt.com>
> 

Applied, thank you.

-- 
Dmitry
Re: [PATCH v5 6/7] Input: matrix_keypad - add settle time after enable all columns
Posted by Manuel Traut 3 weeks, 1 day ago
On Fri, Jan 10, 2025 at 06:49:05AM +0100, Markus Burri wrote:
> Matrix_keypad with high capacity need a longer settle time after enable

matrix keypads with a high capacity need a longer settle time after enable

> all columns and re-enabling interrupts.

> This to give time stable the system and not generate interrupts.
It avoids spurios interrupts by giving the system time to stable.
 
> Add a new optional device-tree property to configure the time before
> enabling interrupts after disable all columns.
> The default is no delay.

The delay for re-enabling the interrupts can be configured by a
device-tree property. The default is no delay.

> Signed-off-by: Markus Burri <markus.burri@mt.com>

Reviewed-by: Manuel Traut <manuel.traut@mt.com>

> ---
>  drivers/input/keyboard/matrix_keypad.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
> index 90148d3..fdb3499 100644
> --- a/drivers/input/keyboard/matrix_keypad.c
> +++ b/drivers/input/keyboard/matrix_keypad.c
> @@ -26,6 +26,7 @@ struct matrix_keypad {
>  	unsigned int row_shift;
>  
>  	unsigned int col_scan_delay_us;
> +	unsigned int all_cols_on_delay_us;
>  	/* key debounce interval in milli-second */
>  	unsigned int debounce_ms;
>  	bool drive_inactive_cols;
> @@ -77,6 +78,9 @@ static void activate_all_cols(struct matrix_keypad *keypad, bool on)
>  
>  	for (col = 0; col < keypad->num_col_gpios; col++)
>  		__activate_col(keypad, col, on);
> +
> +	if (on && keypad->all_cols_on_delay_us)
> +		fsleep(keypad->all_cols_on_delay_us);
>  }
>  
>  static bool row_asserted(struct matrix_keypad *keypad, int row)
> @@ -400,6 +404,8 @@ static int matrix_keypad_probe(struct platform_device *pdev)
>  				 &keypad->debounce_ms);
>  	device_property_read_u32(&pdev->dev, "col-scan-delay-us",
>  				 &keypad->col_scan_delay_us);
> +	device_property_read_u32(&pdev->dev, "all-cols-on-delay-us",
> +				 &keypad->all_cols_on_delay_us);
>  
>  	err = matrix_keypad_init_gpio(pdev, keypad);
>  	if (err)
> -- 
> 2.39.5
>