From: Frieder Schrempf <frieder.schrempf@kontron.de>

This new property can be used for boards which have the SD_VSEL tied
to a fixed low level. The voltage of LDO5 is therefore only controlled
by writing to the LDO5CTRL_L register.

Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
---
Changes for v2:
* new patch
---
 .../bindings/regulator/nxp,pca9450-regulator.yaml           | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml b/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
index 5d0d684186c96..0e19c54aa5f8a 100644
--- a/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
+++ b/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
@@ -49,6 +49,12 @@ properties:
           Properties for single LDO5 regulator.
 
         properties:
+          nxp,sd-vsel-fixed-low:
+            type: boolean
+            description:
+              Let the driver know that SD_VSEL is hardwired to low level and
+              there is no GPIO to get the actual value from.
+
           sd-vsel-gpios:
             description:
               GPIO that can be used to read the current status of the SD_VSEL
-- 
2.46.1

On Wed, Nov 27, 2024 at 05:42:19PM +0100, Frieder Schrempf wrote:
> From: Frieder Schrempf <frieder.schrempf@kontron.de>
> 
> This new property can be used for boards which have the SD_VSEL tied
> to a fixed low level. The voltage of LDO5 is therefore only controlled
> by writing to the LDO5CTRL_L register.
> 
> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
> ---
> Changes for v2:
> * new patch
> ---
>  .../bindings/regulator/nxp,pca9450-regulator.yaml           | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml b/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
> index 5d0d684186c96..0e19c54aa5f8a 100644
> --- a/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
> +++ b/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
> @@ -49,6 +49,12 @@ properties:
>            Properties for single LDO5 regulator.
>  
>          properties:
> +          nxp,sd-vsel-fixed-low:
> +            type: boolean
> +            description:
> +              Let the driver know that SD_VSEL is hardwired to low level and
> +              there is no GPIO to get the actual value from.

Does this mean that if you don't provide the property or a GPIO it is tied
high or High-Z? If so, please mention it here. More likely, given the
context of this patch, no gpio and no tied low property means the driver
should handle things as they used to be - but you should call that out
in your commit message to be clear.

> +
>            sd-vsel-gpios:
>              description:
>                GPIO that can be used to read the current status of the SD_VSEL
> -- 
> 2.46.1
> 

On 28.11.24 6:33 PM, Conor Dooley wrote:
> On Wed, Nov 27, 2024 at 05:42:19PM +0100, Frieder Schrempf wrote:
>> From: Frieder Schrempf <frieder.schrempf@kontron.de>
>>
>> This new property can be used for boards which have the SD_VSEL tied
>> to a fixed low level. The voltage of LDO5 is therefore only controlled
>> by writing to the LDO5CTRL_L register.
>>
>> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
>> ---
>> Changes for v2:
>> * new patch
>> ---
>>  .../bindings/regulator/nxp,pca9450-regulator.yaml           | 6 ++++++
>>  1 file changed, 6 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml b/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
>> index 5d0d684186c96..0e19c54aa5f8a 100644
>> --- a/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
>> +++ b/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
>> @@ -49,6 +49,12 @@ properties:
>>            Properties for single LDO5 regulator.
>>  
>>          properties:
>> +          nxp,sd-vsel-fixed-low:
>> +            type: boolean
>> +            description:
>> +              Let the driver know that SD_VSEL is hardwired to low level and
>> +              there is no GPIO to get the actual value from.
> 
> Does this mean that if you don't provide the property or a GPIO it is tied
> high or High-Z? If so, please mention it here. More likely, given the
> context of this patch, no gpio and no tied low property means the driver
> should handle things as they used to be - but you should call that out
> in your commit message to be clear.

Providing neither 'sd-vsel-gpios', nor 'nxp,sd-vsel-fixed-low' means the
driver has to assume that SD_VSEL is tied high and it has to use the
LDO5CTRL_H for voltage control.

I will make this more clear in the commit message.

This is the original/current behavior of the driver, though it doesn't
match the actual hardware as all known boards actually have the SD_VSEL
connected to the USDHC_VSELECT (which changes state whenever the USDHC
controller wants to switch IO voltage).

Getting rid of this mismatch is one of the main motivations for this series.

> 
>> +
>>            sd-vsel-gpios:
>>              description:
>>                GPIO that can be used to read the current status of the SD_VSEL
>> -- 
>> 2.46.1
>>

On Tue, Dec 10, 2024 at 04:36:41PM +0100, Frieder Schrempf wrote:
> On 28.11.24 6:33 PM, Conor Dooley wrote:
> > On Wed, Nov 27, 2024 at 05:42:19PM +0100, Frieder Schrempf wrote:
> >> From: Frieder Schrempf <frieder.schrempf@kontron.de>
> >>
> >> This new property can be used for boards which have the SD_VSEL tied
> >> to a fixed low level. The voltage of LDO5 is therefore only controlled
> >> by writing to the LDO5CTRL_L register.
> >>
> >> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
> >> ---
> >> Changes for v2:
> >> * new patch
> >> ---
> >>  .../bindings/regulator/nxp,pca9450-regulator.yaml           | 6 ++++++
> >>  1 file changed, 6 insertions(+)
> >>
> >> diff --git a/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml b/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
> >> index 5d0d684186c96..0e19c54aa5f8a 100644
> >> --- a/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
> >> +++ b/Documentation/devicetree/bindings/regulator/nxp,pca9450-regulator.yaml
> >> @@ -49,6 +49,12 @@ properties:
> >>            Properties for single LDO5 regulator.
> >>  
> >>          properties:
> >> +          nxp,sd-vsel-fixed-low:
> >> +            type: boolean
> >> +            description:
> >> +              Let the driver know that SD_VSEL is hardwired to low level and
> >> +              there is no GPIO to get the actual value from.
> > 
> > Does this mean that if you don't provide the property or a GPIO it is tied
> > high or High-Z? If so, please mention it here. More likely, given the
> > context of this patch, no gpio and no tied low property means the driver
> > should handle things as they used to be - but you should call that out
> > in your commit message to be clear.
> 
> Providing neither 'sd-vsel-gpios', nor 'nxp,sd-vsel-fixed-low' means the
> driver has to assume that SD_VSEL is tied high and it has to use the
> LDO5CTRL_H for voltage control.
> 
> I will make this more clear in the commit message.
> 
> This is the original/current behavior of the driver, though it doesn't
> match the actual hardware as all known boards actually have the SD_VSEL
> connected to the USDHC_VSELECT (which changes state whenever the USDHC
> controller wants to switch IO voltage).

That's fine, as long as it is a match for the old behaviour. Sorry for
the delay responding, I was unexpectedly AFK last week.

> 
> Getting rid of this mismatch is one of the main motivations for this series.
> 
> > 
> >> +
> >>            sd-vsel-gpios:
> >>              description:
> >>                GPIO that can be used to read the current status of the SD_VSEL
> >> -- 
> >> 2.46.1
> >>
>