> -----Original Message----- > From: Francesco Dolcini <francesco@xxxxxxxxxx> > Sent: Friday, April 4, 2025 5:42 PM > To: Sherry Sun <sherry.sun@xxxxxxx> > Cc: Hongxing Zhu <hongxing.zhu@xxxxxxx>; l.stach@xxxxxxxxxxxxxx; > lpieralisi@xxxxxxxxxx; kw@xxxxxxxxx; robh@xxxxxxxxxx; > bhelgaas@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx; > conor+dt@xxxxxxxxxx; shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; > kernel@xxxxxxxxxxxxxx; festevam@xxxxxxxxx; dl-linux-imx <linux- > imx@xxxxxxx>; linux-pci@xxxxxxxxxxxxxxx; linux-arm- > kernel@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH V2 2/4] dt-bindings: imx6q-pcie: Add wake-gpios property > > Hello > > On Wed, Dec 13, 2023 at 05:28:48PM +0800, Sherry Sun wrote: > > Add wake-gpios property that can be used to wakeup the host processor. > > > > Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx> > > Reviewed-by: Richard Zhu <hongxing.zhu@xxxxxxx> > > --- > > Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml | 6 ++++++ > > 1 file changed, 6 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml > > b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml > > index 81bbb8728f0f..fba757d937e1 100644 > > --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml > > +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml > > @@ -72,6 +72,12 @@ properties: > > L=operation state) (optional required). > > type: boolean > > > > + wake-gpios: > > + description: If present this property specifies WAKE# sideband signaling > > + to implement wakeup functionality. This is an input GPIO pin for the > Root > > + Port mode here. Host drivers will wakeup the host using the IRQ > > + corresponding to the passed GPIO. > > + > > From what I know it is possible to share the same WAKE# signal for multiple > root ports. Is this going to work fine with this binding? Same question on the > driver. > > We do have design exactly like that, so it's not a theoretical question. > Hi Francesco, The current design doesn't support such case, maybe some changes in the driver could achieve that (mark the wake-gpio as GPIOD_FLAGS_BIT_NONEXCLUSIVE and the interrupt as IRQF_SHARED, etc.). But usually each RC has its own WAKE# pin assigned. We have not come across a case where multiple RC share the same WAKE# pin. Best Regards Sherry
