Re: [PATCH V4 1/2] dt-bindings: leds: pwm: add enable-gpios property

From: Krzysztof Kozlowski
Date: Fri Jul 04 2025 - 03:51:02 EST


On Thu, Jul 03, 2025 at 11:36:10AM +0000, LI Qingwu wrote:
>
>
> > -----Original Message-----
> > From: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> > Sent: Thursday, July 3, 2025 6:55 PM
> > To: LI Qingwu <Qing-wu.Li@xxxxxxxxxxxxxxxxxxxxxxx>; lee@xxxxxxxxxx;
> > pavel@xxxxxxxxxx; robh@xxxxxxxxxx; krzk+dt@xxxxxxxxxx;
> > conor+dt@xxxxxxxxxx; linux-leds@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> > linux-kernel@xxxxxxxxxxxxxxx
> > Cc: GEO-CHHER-bsp-development
> > <bsp-development.geo@xxxxxxxxxxxxxxxxxxxx>
> > Subject: Re: [PATCH V4 1/2] dt-bindings: leds: pwm: add enable-gpios property
> >
> > This email is not from Hexagon’s Office 365 instance. Please be careful while
> > clicking links, opening attachments, or replying to this email.
> >
> >
> > On 03/07/2025 12:27, LI Qingwu wrote:
> > >
> > >
> > >> -----Original Message-----
> > >> From: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> > >> Sent: Thursday, July 3, 2025 5:59 PM
> > >> To: LI Qingwu <Qing-wu.Li@xxxxxxxxxxxxxxxxxxxxxxx>; lee@xxxxxxxxxx;
> > >> pavel@xxxxxxxxxx; robh@xxxxxxxxxx; krzk+dt@xxxxxxxxxx;
> > >> conor+dt@xxxxxxxxxx; linux-leds@xxxxxxxxxxxxxxx;
> > >> conor+devicetree@xxxxxxxxxxxxxxx;
> > >> linux-kernel@xxxxxxxxxxxxxxx
> > >> Cc: GEO-CHHER-bsp-development
> > >> <bsp-development.geo@xxxxxxxxxxxxxxxxxxxx>
> > >> Subject: Re: [PATCH V4 1/2] dt-bindings: leds: pwm: add enable-gpios
> > >> property
> > >>
> > >> This email is not from Hexagon’s Office 365 instance. Please be
> > >> careful while clicking links, opening attachments, or replying to this email.
> >
> > Please drop this, it is not relevant in upstream discussions. Use normal email
> > client which will not produce useless header above.
> >
> >
> > >>
> > >>
> > >> On 03/07/2025 11:34, LI Qingwu wrote:
> > >>> some pwm led driver chips like tps92380 require a separate enable
> > >>> signal
> > >>
> > >> Sentence starts with capital letter.
> > >>
> > >> tps92380 does not have dedicated enable pin. It has VDDIO, which
> > >> serves also enable purpose, but it is a supply.
> > >
> > > So this patch is unacceptable anyway?
> >
> > If you make this patch for tps92380, I think it is not correct. You have entire
> > commit msg to explain the hardware and all unusual things. Having VDDIO and
> > EN pin is unusual, because you do not supply power directly from GPIOs of a SoC.
> > All this should be explained.
>
> Thank you for the feedback, what about rename to power-supply with regulator support ?
> Convert this patch to add regulator support instead of GPIO, using "power-supply" property to control
> LED power, or drop this patch and give up upstream, or what's the better from your point of view?
> appreciate your guidance!

Does it solve your problem? It is surprising that once you say it is
GPIO and once as regulator. How is it in your board?

Regulator is looking as correct hardware description, so that patch
would be fine.

Best regards,
Krzysztof