pinctrl: at91-pio4: fix pull-up/down logic
diff mbox

Message ID 1461074628-20224-1-git-send-email-ludovic.desroches@atmel.com
State New
Headers show

Commit Message

ludovic.desroches@atmel.com April 19, 2016, 2:03 p.m. UTC
The default configuration of a pin is often with a value in the
pull-up/down field at chip reset. So, even if the internal logic of the
controller prevents writing a configuration with pull-up and pull-down at
the same time, we must ensure explicitly this condition before writing the
register.

This was leading to a pull-down condition not taken into account for
instance.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: 776180848b57 ("pinctrl: introduce driver for Atmel PIO4 controller")
Cc: stable@vger.kernel.org #v4.4 and later
---
 drivers/pinctrl/pinctrl-at91-pio4.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

Alexandre Belloni April 19, 2016, 2:37 p.m. UTC | #1
On 19/04/2016 at 16:03:45 +0200, Ludovic Desroches wrote :
> The default configuration of a pin is often with a value in the
> pull-up/down field at chip reset. So, even if the internal logic of the
> controller prevents writing a configuration with pull-up and pull-down at
> the same time, we must ensure explicitly this condition before writing the
> register.
> 
> This was leading to a pull-down condition not taken into account for
> instance.
> 
> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
> Fixes: 776180848b57 ("pinctrl: introduce driver for Atmel PIO4 controller")
> Cc: stable@vger.kernel.org #v4.4 and later
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

> ---
>  drivers/pinctrl/pinctrl-at91-pio4.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/pinctrl/pinctrl-at91-pio4.c b/drivers/pinctrl/pinctrl-at91-pio4.c
> index 629b6fe..75093d7 100644
> --- a/drivers/pinctrl/pinctrl-at91-pio4.c
> +++ b/drivers/pinctrl/pinctrl-at91-pio4.c
> @@ -722,9 +722,11 @@ static int atmel_conf_pin_config_group_set(struct pinctrl_dev *pctldev,
>  			break;
>  		case PIN_CONFIG_BIAS_PULL_UP:
>  			conf |= ATMEL_PIO_PUEN_MASK;
> +			conf &= (~ATMEL_PIO_PDEN_MASK);
>  			break;
>  		case PIN_CONFIG_BIAS_PULL_DOWN:
>  			conf |= ATMEL_PIO_PDEN_MASK;
> +			conf &= (~ATMEL_PIO_PUEN_MASK);
>  			break;
>  		case PIN_CONFIG_DRIVE_OPEN_DRAIN:
>  			if (arg == 0)
> -- 
> 2.5.0
>
Nicolas Ferre April 19, 2016, 3:15 p.m. UTC | #2
Le 19/04/2016 16:03, Ludovic Desroches a écrit :
> The default configuration of a pin is often with a value in the
> pull-up/down field at chip reset. So, even if the internal logic of the
> controller prevents writing a configuration with pull-up and pull-down at
> the same time, we must ensure explicitly this condition before writing the
> register.
> 
> This was leading to a pull-down condition not taken into account for
> instance.
> 
> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
> Fixes: 776180848b57 ("pinctrl: introduce driver for Atmel PIO4 controller")
> Cc: stable@vger.kernel.org #v4.4 and later

Yes, and I can add:
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

and more important:
On a sama5d2 Xplained board:
Tested-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Thanks, bye.

> ---
>  drivers/pinctrl/pinctrl-at91-pio4.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/pinctrl/pinctrl-at91-pio4.c b/drivers/pinctrl/pinctrl-at91-pio4.c
> index 629b6fe..75093d7 100644
> --- a/drivers/pinctrl/pinctrl-at91-pio4.c
> +++ b/drivers/pinctrl/pinctrl-at91-pio4.c
> @@ -722,9 +722,11 @@ static int atmel_conf_pin_config_group_set(struct pinctrl_dev *pctldev,
>  			break;
>  		case PIN_CONFIG_BIAS_PULL_UP:
>  			conf |= ATMEL_PIO_PUEN_MASK;
> +			conf &= (~ATMEL_PIO_PDEN_MASK);
>  			break;
>  		case PIN_CONFIG_BIAS_PULL_DOWN:
>  			conf |= ATMEL_PIO_PDEN_MASK;
> +			conf &= (~ATMEL_PIO_PUEN_MASK);
>  			break;
>  		case PIN_CONFIG_DRIVE_OPEN_DRAIN:
>  			if (arg == 0)
>
Linus Walleij April 29, 2016, 9:17 a.m. UTC | #3
On Tue, Apr 19, 2016 at 4:03 PM, Ludovic Desroches
<ludovic.desroches@atmel.com> wrote:

> The default configuration of a pin is often with a value in the
> pull-up/down field at chip reset. So, even if the internal logic of the
> controller prevents writing a configuration with pull-up and pull-down at
> the same time, we must ensure explicitly this condition before writing the
> register.
>
> This was leading to a pull-down condition not taken into account for
> instance.
>
> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
> Fixes: 776180848b57 ("pinctrl: introduce driver for Atmel PIO4 controller")
> Cc: stable@vger.kernel.org #v4.4 and later

Patch applied for fixes with the ACKs.

Yours,
Linus Walleij
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Patch
diff mbox

diff --git a/drivers/pinctrl/pinctrl-at91-pio4.c b/drivers/pinctrl/pinctrl-at91-pio4.c
index 629b6fe..75093d7 100644
--- a/drivers/pinctrl/pinctrl-at91-pio4.c
+++ b/drivers/pinctrl/pinctrl-at91-pio4.c
@@ -722,9 +722,11 @@  static int atmel_conf_pin_config_group_set(struct pinctrl_dev *pctldev,
 			break;
 		case PIN_CONFIG_BIAS_PULL_UP:
 			conf |= ATMEL_PIO_PUEN_MASK;
+			conf &= (~ATMEL_PIO_PDEN_MASK);
 			break;
 		case PIN_CONFIG_BIAS_PULL_DOWN:
 			conf |= ATMEL_PIO_PDEN_MASK;
+			conf &= (~ATMEL_PIO_PUEN_MASK);
 			break;
 		case PIN_CONFIG_DRIVE_OPEN_DRAIN:
 			if (arg == 0)