On Saturday 01 October 2022 17:56:26 Lukas Wunner wrote: > On Sat, Oct 01, 2022 at 12:57:44AM +0530, Vidya Sagar wrote: > > Provide a way for the firmware to tell the OS about the GPIO that can be > > used to get the Hot-Plug and Unplug events. > [...] > > --- a/Documentation/devicetree/bindings/pci/pci.txt > > +++ b/Documentation/devicetree/bindings/pci/pci.txt > > @@ -32,6 +32,10 @@ driver implementation may support the following properties: > > root port to downstream device and host bridge drivers can do programming > > which depends on CLKREQ signal existence. For example, programming root port > > not to advertise ASPM L1 Sub-States support if there is no CLKREQ signal. > > +- hotplug-gpios: > > + If present this property specifies the GPIO to be used for Hot-Plug/Unplug > > + functionality. It is used by the PCIe GPIO Hot-Plug core driver for > > + PCIe device Hot-Plug/Unplug events. > > Please specify the GPIO's semantics in more detail: > Is the pin high as long as presence of a card is detected? Hello! In PCIe is this semantics called "Presence Detect" (see PCIe Slot Capabilities). So should it be rather named "presence-detect-gpios" instead of hotplug? > Or does it pulse when a hotplug/unplug event occurs? > > Thanks, > > Lukas
