Re: [PATCH 7/7] pwm: dwc: add snps,pwm-number to limit pwm count

From: Rob Herring
Date: Mon Jul 18 2022 - 16:08:35 EST


On Tue, Jul 12, 2022 at 11:01:13AM +0100, Ben Dooks wrote:
> Add snps,pwm-number property to indicate if the block does not have
> all 8 of the PWM blocks.
>
> Not sure if this should be a general PWM property consider optional
> for all PWM types, so have added a specific one here (there is only
> one other controller with a property for PWM count at the moment)
>
> Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/pwm/pwm-synposys.yaml | 5 +++++
> drivers/pwm/pwm-dwc.c | 8 ++++++++
> 2 files changed, 13 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pwm/pwm-synposys.yaml b/Documentation/devicetree/bindings/pwm/pwm-synposys.yaml
> index 38ac0da75272..15bdf764b46a 100644
> --- a/Documentation/devicetree/bindings/pwm/pwm-synposys.yaml
> +++ b/Documentation/devicetree/bindings/pwm/pwm-synposys.yaml
> @@ -30,11 +30,16 @@ properties:
> - items:
> - const: snps,pwm
>
> + snps,pwm-number:
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description: u32 value representing the number of PWM devices

Why do we need to know this? Are you going to have a consumer to a
non-existent PWM? If you do need to know how many, it should be implied
by the compatible string.

Rob