[PATCH v2 1/3] dt-bindings: watchdog: sunxi: Add compatible for R329

Samuel Holland samuel at sholland.org
Thu Aug 19 21:04:52 PDT 2021


On 8/18/21 4:07 AM, Maxime Ripard wrote:
> Hi,
> 
> On Wed, Aug 04, 2021 at 11:57:14PM -0500, Samuel Holland wrote:
>> On existing SoCs, the watchdog has a single clock input: HOSC (OSC24M)
>> divided by 750.  However, starting with R329, LOSC (OSC32k) is added as
>> an alternative clock source, with a bit to switch between them.
>>
>> Since 24 MHz / 750 == 32 kHz, not 32.768 kHz, the hardware adjusts the
>> cycle counts to keep the timeouts independent of the clock source. This
>> keeps the programming interface backward-compatible.
>>
>> R329 also adds two new registers, to allow software to immediately drive
>> the SoC reset signal.
>>
>> Signed-off-by: Samuel Holland <samuel at sholland.org>
>> ---
>> Changes v1 to v2:
>>  - Switch from enum to const
>>  - Add descriptions to "clocks" items
>>
>>  .../watchdog/allwinner,sun4i-a10-wdt.yaml     | 32 ++++++++++++++++++-
>>  1 file changed, 31 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
>> index 9aa3c313c49f..8fa5b0d32381 100644
>> --- a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
>> +++ b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
>> @@ -24,6 +24,7 @@ properties:
>>                - allwinner,sun50i-a100-wdt
>>                - allwinner,sun50i-h6-wdt
>>                - allwinner,sun50i-h616-wdt
>> +              - allwinner,sun50i-r329-wdt
>>            - const: allwinner,sun6i-a31-wdt
>>        - items:
>>            - const: allwinner,suniv-f1c100s-wdt
>> @@ -33,7 +34,18 @@ properties:
>>      maxItems: 1
>>  
>>    clocks:
>> -    maxItems: 1
>> +    minItems: 1
>> +    maxItems: 2
>> +    items:
>> +      - description: High-frequency oscillator input, divided internally
>> +      - description: Low-frequency oscillator input, only found on some variants
>> +
>> +  clock-names:
>> +    minItems: 1
>> +    maxItems: 2
>> +    items:
>> +      - const: hosc
>> +      - const: losc
>>  
>>    interrupts:
>>      maxItems: 1
>> @@ -44,6 +56,24 @@ required:
>>    - clocks
>>    - interrupts
>>  
>> +if:
>> +  properties:
>> +    compatible:
>> +      contains:
>> +        enum:
>> +          - allwinner,sun50i-r329-wdt
>> +
>> +then:
>> +  properties:
>> +    clocks:
>> +      minItems: 2
>> +
>> +    clock-names:
>> +      minItems: 2
>> +
>> +  required:
>> +    - clock-names
>> +
> 
> We should also make sure through an else clause that all the other SoCs
> have a length of one for both clocks and clock-names

Yes, I'll do that for v3.

> Also, it looks like you forgot the patch to enable the compatible in the
> driver?

R329 has a fallback to A31, so it doesn't need any changes to the driver.

Regards,
Samuel



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