Hi Laurent, On Tue, Mar 16, 2021 at 12:15:16AM +0200, Laurent Pinchart wrote: > Hi Jacopo, > > Thank you for the patch. > > On Mon, Mar 15, 2021 at 05:30:25PM +0100, Jacopo Mondi wrote: > > The MAX9286 GMSL deserializer features gpio controller capabilities, > > as it provides 2 GPIO lines. > > > > As establishing a regulator that uses one of the GPIO lines and > > enabling/disabling it at run-time in the max9286 won't work due to > > a circular dependency on the gpio-controller/regulator creation, allow > > the usage of a gpio-hog for that purpose. > > > > The usage of the gpio-hog is required in designs where the MAX9286 > > GPIO lines control the remote cameras power. > > > > Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx> > > That's really a workaround until we can find a good solution, do we have > to officially support it in the DT bindings ? > That's an interesting question. The 'good' solution implies resolving the circular dependency on the regulator/gpio-controller creation and I feel like it might take a while to find a proper solution. In the meantime, all designs like Eagle that control the camera power through a MAX9286 gpio have to rely on this. I'll go with the majority here: either we add this and upstream the gmsl .dtsi for eagle, or we keep out-of-tree patches :/ > > --- > > .../bindings/media/i2c/maxim,max9286.yaml | 16 ++++++++++++++++ > > 1 file changed, 16 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml b/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml > > index ee16102fdfe7..9038300e373c 100644 > > --- a/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml > > +++ b/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml > > @@ -177,6 +177,22 @@ properties: > > > > additionalProperties: false > > > > +patternProperties: > > + "^(hog-[0-9]+|.+-hog(-[0-9]+)?)$": > > + type: object > > + properties: > > + gpio-hog: true > > + gpios: true > > + output-low: true > > + line-name: true > > + > > + required: > > + - gpio-hog > > + - gpios > > + - output-low > > + > > + additionalProperties: false > > + > > required: > > - compatible > > - reg > > -- > Regards, > > Laurent Pinchart
