Re: [PATCH 1/2] dt-bindings: pwm: brcm,bcm7038: Document the 'open-drain' property
From: Florian Fainelli <florian.fainelli@broadcom.com>
Date: 2024-10-29 16:04:01
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On 10/29/24 03:44, Uwe Kleine-König wrote:
quoted hunk ↗ jump to hunk
Hello, On Tue, Oct 15, 2024 at 10:07:10AM -0700, Florian Fainelli wrote:quoted
On 10/15/24 09:32, Rob Herring wrote:quoted
Another thing to consider is for any PWM controller with more than 1 output, you might want this to be per output and therefore should be a flag in the cells.Yes, that is a good point, this controller has two channels, so it seems like increasing the #pwm-cells might be the way to go.So the idea is something like:diff --git a/include/dt-bindings/pwm/pwm.h b/include/dt-bindings/pwm/pwm.h index ab9a077e3c7d..d18b006a7399 100644 --- a/include/dt-bindings/pwm/pwm.h +++ b/include/dt-bindings/pwm/pwm.h@@ -11,5 +11,6 @@ #define _DT_BINDINGS_PWM_PWM_H #define PWM_POLARITY_INVERTED (1 << 0) +#define PWM_OUTPUT_OPEN_DRAIN (1 << 1) #endifand then add support for that to the core and drivers? There is some intersection with pinctrl (depending on hardware). I wonder if abstracting this somehow using the typical pinctrl properties would be a saner option??
But what if the pin is not managed by a pinctrl provider? I have started going the route of implementing the PWM_OUTPUT_OPEN_DRAIN bit as an additional specifier in the #pwm-cells, but I am not sure to what extent this should be allowed to be changed at runtime. -- Florian