Hello,
On 04/05/2022 15:06:13+0200, Valentin Caron wrote:
> STM32 RTC can pulse some SOC pins when an alarm of RTC expires.
>
> This patch adds property to activate alarm A output. The pulse can
> output on three pins RTC_OUT1, RTC_OUT2, RTC_OUT2_RMP
> (PC13, PB2, PI8 on stm32mp15) (PC13, PB2, PI1 on stm32mp13).
>
> Signed-off-by: Valentin Caron <[email protected]>
> ---
> .../devicetree/bindings/rtc/st,stm32-rtc.yaml | 19 ++++++++++++++++++-
> 1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
> index 56d46ea35c5d..71e02604e8de 100644
> --- a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
> +++ b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
> @@ -59,6 +59,13 @@ properties:
> Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the supported values.
> Pinctrl state named "default" may be defined to reserve pin for RTC output.
>
> + st,alarm:
> + $ref: "/schemas/types.yaml#/definitions/uint32"
> + description: |
> + To select and enable RTC Alarm A output.
> + Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the supported values.
> + Pinctrl state named "default" may be defined to reserve pin for RTC output.
> +
> allOf:
> - if:
> properties:
> @@ -75,6 +82,9 @@ allOf:
> st,lsco:
> maxItems: 0
>
> + st,alarm:
> + maxItems: 0
> +
> clock-names: false
>
> required:
> @@ -95,6 +105,9 @@ allOf:
> st,lsco:
> maxItems: 0
>
> + st,alarm:
> + maxItems: 0
> +
> required:
> - clock-names
> - st,syscfg
> @@ -117,6 +130,9 @@ allOf:
> st,lsco:
> maxItems: 1
>
> + st,alarm:
> + maxItems: 1
> +
> required:
> - clock-names
>
> @@ -153,8 +169,9 @@ examples:
> clocks = <&rcc RTCAPB>, <&rcc RTC>;
> clock-names = "pclk", "rtc_ck";
> interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>;
> + st,alarm = <RTC_OUT1>;
> st,lsco = <RTC_OUT2_RMP>;
Shouldn't that be exactly the opposite? You have two pins that can
output different functions. The property should be the pin and the value
the function. I'd go even further and I would say this is actually
pinmuxing.
--
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
Hi Alexandre,
On 5/4/22 22:27, Alexandre Belloni wrote:
> Hello,
>
> On 04/05/2022 15:06:13+0200, Valentin Caron wrote:
>> STM32 RTC can pulse some SOC pins when an alarm of RTC expires.
>>
>> This patch adds property to activate alarm A output. The pulse can
>> output on three pins RTC_OUT1, RTC_OUT2, RTC_OUT2_RMP
>> (PC13, PB2, PI8 on stm32mp15) (PC13, PB2, PI1 on stm32mp13).
>>
>> Signed-off-by: Valentin Caron <[email protected]>
>> ---
>> .../devicetree/bindings/rtc/st,stm32-rtc.yaml | 19 ++++++++++++++++++-
>> 1 file changed, 18 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
>> index 56d46ea35c5d..71e02604e8de 100644
>> --- a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
>> +++ b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
>> @@ -59,6 +59,13 @@ properties:
>> Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the supported values.
>> Pinctrl state named "default" may be defined to reserve pin for RTC output.
>>
>> + st,alarm:
>> + $ref: "/schemas/types.yaml#/definitions/uint32"
>> + description: |
>> + To select and enable RTC Alarm A output.
>> + Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the supported values.
>> + Pinctrl state named "default" may be defined to reserve pin for RTC output.
>> +
>> allOf:
>> - if:
>> properties:
>> @@ -75,6 +82,9 @@ allOf:
>> st,lsco:
>> maxItems: 0
>>
>> + st,alarm:
>> + maxItems: 0
>> +
>> clock-names: false
>>
>> required:
>> @@ -95,6 +105,9 @@ allOf:
>> st,lsco:
>> maxItems: 0
>>
>> + st,alarm:
>> + maxItems: 0
>> +
>> required:
>> - clock-names
>> - st,syscfg
>> @@ -117,6 +130,9 @@ allOf:
>> st,lsco:
>> maxItems: 1
>>
>> + st,alarm:
>> + maxItems: 1
>> +
>> required:
>> - clock-names
>>
>> @@ -153,8 +169,9 @@ examples:
>> clocks = <&rcc RTCAPB>, <&rcc RTC>;
>> clock-names = "pclk", "rtc_ck";
>> interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>;
>> + st,alarm = <RTC_OUT1>;
>> st,lsco = <RTC_OUT2_RMP>;
> Shouldn't that be exactly the opposite? You have two pins that can
> output different functions. The property should be the pin and the value
> the function. I'd go even further and I would say this is actually
> pinmuxing.
>
You're right, if the property is the pin and the value the function,
this looks like a pinctrl node.
We choose to develop theses functionalities in the reverse order, to
avoid the complexity of adding
the pinctrl framework to our driver. Moreover, LSCO and AlarmA may
haven't a peripheral client and
this would probably require to also implement pinctrl hogging.
Is the implementation that we have proposed is acceptable regarding
theses elements ?
Thank you,
Valentin
Hi Alexandre,
May I have your view regarding these new elements ?
Thank you,
Valentin
On 5/23/22 14:34, Valentin CARON wrote:
> Hi Alexandre,
>
> On 5/4/22 22:27, Alexandre Belloni wrote:
>> Hello,
>>
>> On 04/05/2022 15:06:13+0200, Valentin Caron wrote:
>>> STM32 RTC can pulse some SOC pins when an alarm of RTC expires.
>>>
>>> This patch adds property to activate alarm A output. The pulse can
>>> output on three pins RTC_OUT1, RTC_OUT2, RTC_OUT2_RMP
>>> (PC13, PB2, PI8 on stm32mp15) (PC13, PB2, PI1 on stm32mp13).
>>>
>>> Signed-off-by: Valentin Caron <[email protected]>
>>> ---
>>> .../devicetree/bindings/rtc/st,stm32-rtc.yaml | 19
>>> ++++++++++++++++++-
>>> 1 file changed, 18 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
>>> b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
>>> index 56d46ea35c5d..71e02604e8de 100644
>>> --- a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
>>> +++ b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
>>> @@ -59,6 +59,13 @@ properties:
>>> Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the
>>> supported values.
>>> Pinctrl state named "default" may be defined to reserve pin
>>> for RTC output.
>>> + st,alarm:
>>> + $ref: "/schemas/types.yaml#/definitions/uint32"
>>> + description: |
>>> + To select and enable RTC Alarm A output.
>>> + Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the
>>> supported values.
>>> + Pinctrl state named "default" may be defined to reserve pin
>>> for RTC output.
>>> +
>>> allOf:
>>> - if:
>>> properties:
>>> @@ -75,6 +82,9 @@ allOf:
>>> st,lsco:
>>> maxItems: 0
>>> + st,alarm:
>>> + maxItems: 0
>>> +
>>> clock-names: false
>>> required:
>>> @@ -95,6 +105,9 @@ allOf:
>>> st,lsco:
>>> maxItems: 0
>>> + st,alarm:
>>> + maxItems: 0
>>> +
>>> required:
>>> - clock-names
>>> - st,syscfg
>>> @@ -117,6 +130,9 @@ allOf:
>>> st,lsco:
>>> maxItems: 1
>>> + st,alarm:
>>> + maxItems: 1
>>> +
>>> required:
>>> - clock-names
>>> @@ -153,8 +169,9 @@ examples:
>>> clocks = <&rcc RTCAPB>, <&rcc RTC>;
>>> clock-names = "pclk", "rtc_ck";
>>> interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>;
>>> + st,alarm = <RTC_OUT1>;
>>> st,lsco = <RTC_OUT2_RMP>;
>> Shouldn't that be exactly the opposite? You have two pins that can
>> output different functions. The property should be the pin and the value
>> the function. I'd go even further and I would say this is actually
>> pinmuxing.
>>
> You're right, if the property is the pin and the value the function,
> this looks like a pinctrl node.
> We choose to develop theses functionalities in the reverse order, to
> avoid the complexity of adding
> the pinctrl framework to our driver. Moreover, LSCO and AlarmA may
> haven't a peripheral client and
> this would probably require to also implement pinctrl hogging.
>
> Is the implementation that we have proposed is acceptable regarding
> theses elements ?
>
> Thank you,
> Valentin
>
On 23/05/2022 14:34:22+0200, Valentin CARON wrote:
> Hi Alexandre,
>
> On 5/4/22 22:27, Alexandre Belloni wrote:
> > Hello,
> >
> > On 04/05/2022 15:06:13+0200, Valentin Caron wrote:
> > > STM32 RTC can pulse some SOC pins when an alarm of RTC expires.
> > >
> > > This patch adds property to activate alarm A output. The pulse can
> > > output on three pins RTC_OUT1, RTC_OUT2, RTC_OUT2_RMP
> > > (PC13, PB2, PI8 on stm32mp15) (PC13, PB2, PI1 on stm32mp13).
> > >
> > > Signed-off-by: Valentin Caron <[email protected]>
> > > ---
> > > .../devicetree/bindings/rtc/st,stm32-rtc.yaml | 19 ++++++++++++++++++-
> > > 1 file changed, 18 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
> > > index 56d46ea35c5d..71e02604e8de 100644
> > > --- a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
> > > +++ b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
> > > @@ -59,6 +59,13 @@ properties:
> > > Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the supported values.
> > > Pinctrl state named "default" may be defined to reserve pin for RTC output.
> > > + st,alarm:
> > > + $ref: "/schemas/types.yaml#/definitions/uint32"
> > > + description: |
> > > + To select and enable RTC Alarm A output.
> > > + Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the supported values.
> > > + Pinctrl state named "default" may be defined to reserve pin for RTC output.
> > > +
> > > allOf:
> > > - if:
> > > properties:
> > > @@ -75,6 +82,9 @@ allOf:
> > > st,lsco:
> > > maxItems: 0
> > > + st,alarm:
> > > + maxItems: 0
> > > +
> > > clock-names: false
> > > required:
> > > @@ -95,6 +105,9 @@ allOf:
> > > st,lsco:
> > > maxItems: 0
> > > + st,alarm:
> > > + maxItems: 0
> > > +
> > > required:
> > > - clock-names
> > > - st,syscfg
> > > @@ -117,6 +130,9 @@ allOf:
> > > st,lsco:
> > > maxItems: 1
> > > + st,alarm:
> > > + maxItems: 1
> > > +
> > > required:
> > > - clock-names
> > > @@ -153,8 +169,9 @@ examples:
> > > clocks = <&rcc RTCAPB>, <&rcc RTC>;
> > > clock-names = "pclk", "rtc_ck";
> > > interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>;
> > > + st,alarm = <RTC_OUT1>;
> > > st,lsco = <RTC_OUT2_RMP>;
> > Shouldn't that be exactly the opposite? You have two pins that can
> > output different functions. The property should be the pin and the value
> > the function. I'd go even further and I would say this is actually
> > pinmuxing.
> >
> You're right, if the property is the pin and the value the function, this
> looks like a pinctrl node.
> We choose to develop theses functionalities in the reverse order, to avoid
> the complexity of adding
> the pinctrl framework to our driver. Moreover, LSCO and AlarmA may haven't a
> peripheral client and
> this would probably require to also implement pinctrl hogging.
>
> Is the implementation that we have proposed is acceptable regarding theses
> elements ?
>
I still think that the pin has to be the property and the function the value.
Or we could find a generic name and provide an array of pin, function
pair
Or, go for pinmuxing
My point here is that this is a common feature an RTCs and I don't want
every vendor to come up with their own properties.
Regards,
--
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com