diff mbox series

ARM: dts: stm32: Consistently enable internal pull-ups for SD bus

Message ID 20201009210735.243532-1-marex@denx.de
State Rejected
Delegated to: Patrick Delaunay
Headers show
Series ARM: dts: stm32: Consistently enable internal pull-ups for SD bus | expand

Commit Message

Marek Vasut Oct. 9, 2020, 9:07 p.m. UTC
The default state of SD bus and clock line is logical HI. SD card IO is
open-drain and pulls the bus lines LO. Always enable the SD bus pull ups
to guarantee this behavior. Note that on systems with bus voltage level
shifter on the SD bus, the pull ups might also be built into the level
shifter, however that should have no negative impact.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
---
 arch/arm/dts/stm32mp15-pinctrl.dtsi | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Comments

Patrick DELAUNAY Dec. 9, 2020, 10:22 a.m. UTC | #1
Hi Marek,

On 12/9/20 11:11 AM, Patrick DELAUNAY wrote:
> From: Marek Vasut <marex@denx.de>
> Sent: vendredi 9 octobre 2020 23:08
>
> The default state of SD bus and clock line is logical HI. SD card IO is open-drain and pulls the bus lines LO. Always enable the SD bus pull ups to guarantee this behavior. Note that on systems with bus voltage level shifter on the SD bus, the pull ups might also be built into the level shifter, however that should have no negative impact.
>
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Patrice Chotard <patrice.chotard@st.com>
> Cc: Patrick Delaunay <patrick.delaunay@st.com>
> ---
>   arch/arm/dts/stm32mp15-pinctrl.dtsi | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm/dts/stm32mp15-pinctrl.dtsi b/arch/arm/dts/stm32mp15-pinctrl.dtsi
> index 154832983c..2f8ff44a7a 100644
> --- a/arch/arm/dts/stm32mp15-pinctrl.dtsi
> +++ b/arch/arm/dts/stm32mp15-pinctrl.dtsi
> @@ -1184,13 +1184,13 @@
>   				 <STM32_PINMUX('D', 2, AF12)>; /* SDMMC1_CMD */
>   			slew-rate = <1>;
>   			drive-push-pull;
> -			bias-disable;
> +			bias-pull-up;
>   		};
>   		pins2 {
>   			pinmux = <STM32_PINMUX('C', 12, AF12)>; /* SDMMC1_CK */
>   			slew-rate = <2>;
>   			drive-push-pull;
> -			bias-disable;
> +			bias-pull-up;
>   		};
>   	};
>   
> @@ -1340,13 +1340,13 @@
>   				 <STM32_PINMUX('G', 6, AF10)>; /* SDMMC2_CMD */
>   			slew-rate = <1>;
>   			drive-push-pull;
> -			bias-disable;
> +			bias-pull-up;
>   		};
>   		pins2 {
>   			pinmux = <STM32_PINMUX('E', 3, AF9)>; /* SDMMC2_CK */
>   			slew-rate = <2>;
>   			drive-push-pull;
> -			bias-disable;
> +			bias-pull-up;
>   		};
>   	};
>   
> --
> 2.28.0
>
I don't see consensus on this device tree modification in Linux kernel 
side [1].

And for the DH board the modification is now done in SOM dtsi files 
after [2].

So can I close this patchset in patchwork ?

And if the modification is accepted in kernel device tree , I will get 
it with my next device

tree alignment...

[1] 
https://st-md-mailman.stormreply.com/pipermail/linux-stm32/2020-October/008554.html

[2] "ARM: dts: stm32: Enable internal pull-ups for SDMMC1 on DHCOM SoM 
<http://patchwork.ozlabs.org/project/uboot/list/?series=217761>"

http://patchwork.ozlabs.org/project/uboot/list/?series=217761&state=*


Regards

Patrick
Marek Vasut Dec. 9, 2020, 1:57 p.m. UTC | #2
On 12/9/20 11:22 AM, Patrick DELAUNAY wrote:

Hi,

[...]

>> @@ -1340,13 +1340,13 @@
>>                    <STM32_PINMUX('G', 6, AF10)>; /* SDMMC2_CMD */
>>               slew-rate = <1>;
>>               drive-push-pull;
>> -            bias-disable;
>> +            bias-pull-up;
>>           };
>>           pins2 {
>>               pinmux = <STM32_PINMUX('E', 3, AF9)>; /* SDMMC2_CK */
>>               slew-rate = <2>;
>>               drive-push-pull;
>> -            bias-disable;
>> +            bias-pull-up;
>>           };
>>       };
>> -- 
>> 2.28.0
>>
> I don't see consensus on this device tree modification in Linux kernel 
> side [1].
> 
> And for the DH board the modification is now done in SOM dtsi files 
> after [2].
> 
> So can I close this patchset in patchwork ?

Yes

> And if the modification is accepted in kernel device tree , I will get 
> it with my next device
> 
> tree alignment...

I plan to realign the DTs after 2021.01 is out too.
diff mbox series

Patch

diff --git a/arch/arm/dts/stm32mp15-pinctrl.dtsi b/arch/arm/dts/stm32mp15-pinctrl.dtsi
index 154832983c..2f8ff44a7a 100644
--- a/arch/arm/dts/stm32mp15-pinctrl.dtsi
+++ b/arch/arm/dts/stm32mp15-pinctrl.dtsi
@@ -1184,13 +1184,13 @@ 
 				 <STM32_PINMUX('D', 2, AF12)>; /* SDMMC1_CMD */
 			slew-rate = <1>;
 			drive-push-pull;
-			bias-disable;
+			bias-pull-up;
 		};
 		pins2 {
 			pinmux = <STM32_PINMUX('C', 12, AF12)>; /* SDMMC1_CK */
 			slew-rate = <2>;
 			drive-push-pull;
-			bias-disable;
+			bias-pull-up;
 		};
 	};
 
@@ -1340,13 +1340,13 @@ 
 				 <STM32_PINMUX('G', 6, AF10)>; /* SDMMC2_CMD */
 			slew-rate = <1>;
 			drive-push-pull;
-			bias-disable;
+			bias-pull-up;
 		};
 		pins2 {
 			pinmux = <STM32_PINMUX('E', 3, AF9)>; /* SDMMC2_CK */
 			slew-rate = <2>;
 			drive-push-pull;
-			bias-disable;
+			bias-pull-up;
 		};
 	};