Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1232136 > unrolled thread

Re: [PATCH] ARM: at91/dt: pullup dbgu rx instead of tx

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  Re: [PATCH] ARM: at91/dt: pullup dbgu rx instead of tx Alexandre Belloni <alexandre.belloni@free-electrons.com> - 2015-09-24 16:50 +0200
    Re: [PATCH] ARM: at91/dt: pullup dbgu rx instead of tx Peter Rosin <peda@lysator.liu.se> - 2015-09-24 17:30 +0200
      Re: [PATCH] ARM: at91/dt: pullup dbgu rx instead of tx Alexandre Belloni <alexandre.belloni@free-electrons.com> - 2015-09-24 18:30 +0200

#1232136 — Re: [PATCH] ARM: at91/dt: pullup dbgu rx instead of tx

Hi Peter,

Thanks for the patch but you actually got beaten by Sylvain:
http://lists.infradead.org/pipermail/linux-arm-kernel/2015-September/368426.html

On 24/09/2015 at 16:44:15 +0200, Peter Rosin wrote :
> From: Peter Rosin <peda@axentia.se>
> 
> It seems pointless to pullup the tx line, but there is value in pulling
> up the rx line.
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Peter Rosin <peda@axentia.se>
> ---
>  arch/arm/boot/dts/sama5d3.dtsi |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/boot/dts/sama5d3.dtsi b/arch/arm/boot/dts/sama5d3.dtsi
> index 9e2444b07bce..304a40c5552a 100644
> --- a/arch/arm/boot/dts/sama5d3.dtsi
> +++ b/arch/arm/boot/dts/sama5d3.dtsi
> @@ -545,8 +545,8 @@
>  				dbgu {
>  					pinctrl_dbgu: dbgu-0 {
>  						atmel,pins =
> -							<AT91_PIOB 30 AT91_PERIPH_A AT91_PINCTRL_NONE	/* PB30 periph A */
> -							 AT91_PIOB 31 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;	/* PB31 periph A with pullup */
> +							<AT91_PIOB 30 AT91_PERIPH_A AT91_PINCTRL_PULL_UP	/* PB30 periph A with pullup */
> +							 AT91_PIOB 31 AT91_PERIPH_A AT91_PINCTRL_NONE>;	/* PB31 periph A */
>  					};
>  				};
>  
> -- 
> 1.7.10.4
> 

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [next] | [standalone]

#1232189

On 2015-09-24 16:47, Alexandre Belloni wrote:
> Hi Peter,
> 
> Thanks for the patch but you actually got beaten by Sylvain:
> http://lists.infradead.org/pipermail/linux-arm-kernel/2015-September/368426.html

Ok, great!

I just noticed that other ports have the same problem in sama5d3.dtsi. E.g.

	uart1 {
		pinctrl_uart1: uart1-0 {
			atmel,pins =
				<AT91_PIOA 30 AT91_PERIPH_B AT91_PINCTRL_NONE   /* conflicts with TWD0, ISI_VSYNC */
				 AT91_PIOA 31 AT91_PERIPH_B AT91_PINCTRL_PULL_UP>;      /* conflicts with TWCK0, ISI_HSYNC */
		};
	};

Given that the original bug I found spread all over the map, it seems
like someone was confused when the pull-ups were originally added.
Someone (else?) at Atmel needs to audit this so that pull-ups are
added on the rx-pins instead of the tx-pins.

Cheers,
Peter

> On 24/09/2015 at 16:44:15 +0200, Peter Rosin wrote :
>> From: Peter Rosin <peda@axentia.se>
>>
>> It seems pointless to pullup the tx line, but there is value in pulling
>> up the rx line.
>>
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Peter Rosin <peda@axentia.se>
>> ---
>>  arch/arm/boot/dts/sama5d3.dtsi |    4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm/boot/dts/sama5d3.dtsi b/arch/arm/boot/dts/sama5d3.dtsi
>> index 9e2444b07bce..304a40c5552a 100644
>> --- a/arch/arm/boot/dts/sama5d3.dtsi
>> +++ b/arch/arm/boot/dts/sama5d3.dtsi
>> @@ -545,8 +545,8 @@
>>  				dbgu {
>>  					pinctrl_dbgu: dbgu-0 {
>>  						atmel,pins =
>> -							<AT91_PIOB 30 AT91_PERIPH_A AT91_PINCTRL_NONE	/* PB30 periph A */
>> -							 AT91_PIOB 31 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;	/* PB31 periph A with pullup */
>> +							<AT91_PIOB 30 AT91_PERIPH_A AT91_PINCTRL_PULL_UP	/* PB30 periph A with pullup */
>> +							 AT91_PIOB 31 AT91_PERIPH_A AT91_PINCTRL_NONE>;	/* PB31 periph A */
>>  					};
>>  				};
>>  
>> -- 
>> 1.7.10.4
>>
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1232240

On 24/09/2015 at 17:22:54 +0200, Peter Rosin wrote :
> I just noticed that other ports have the same problem in sama5d3.dtsi. E.g.
> 
> 	uart1 {
> 		pinctrl_uart1: uart1-0 {
> 			atmel,pins =
> 				<AT91_PIOA 30 AT91_PERIPH_B AT91_PINCTRL_NONE   /* conflicts with TWD0, ISI_VSYNC */
> 				 AT91_PIOA 31 AT91_PERIPH_B AT91_PINCTRL_PULL_UP>;      /* conflicts with TWCK0, ISI_HSYNC */
> 		};
> 	};
> 
> Given that the original bug I found spread all over the map, it seems
> like someone was confused when the pull-ups were originally added.
> Someone (else?) at Atmel needs to audit this so that pull-ups are
> added on the rx-pins instead of the tx-pins.
> 

Sure, that is the plan!
Thanks again for the report.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web