Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:1 as permitted sender) client-ip=2620:137:e000::3:1;
Date:   Fri, 8 Dec 2023 14:55:45 -0600
From:   Rob Herring <robh@kernel.org>
To:     Lucas Stach <l.stach@pengutronix.de>
Cc:     Sherry Sun <sherry.sun@nxp.com>, hongxing.zhu@nxp.com,
        lpieralisi@kernel.org, kw@linux.com, bhelgaas@google.com,
        krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
        shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de,
        festevam@gmail.com, linux-imx@nxp.com, linux-pci@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/4] dt-bindings: imx6q-pcie: Add host-wake-gpio property
Message-ID: <20231208205545.GA2675840-robh@kernel.org>
References: <20231208091355.1417292-1-sherry.sun@nxp.com>
 <20231208091355.1417292-3-sherry.sun@nxp.com>
 <83ca3d88cdaa7bc6e6bd3c4e88518b155a6b0f05.camel@pengutronix.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <83ca3d88cdaa7bc6e6bd3c4e88518b155a6b0f05.camel@pengutronix.de>
Precedence: bulk

On Fri, Dec 08, 2023 at 11:00:19AM +0100, Lucas Stach wrote:
> Hi Sherry,
> 
> Am Freitag, dem 08.12.2023 um 17:13 +0800 schrieb Sherry Sun:
> > Add host-wake-gpio property that can be used to wakeup the host
> > processor.
> > 
> > Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
> > Reviewed-by: Richard Zhu <hongxing.zhu@nxp.com>
> > ---
> >  Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml | 4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml
> > index 81bbb8728f0f..944f0f961809 100644
> > --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml
> > +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml
> > @@ -72,6 +72,10 @@ properties:
> >        L=operation state) (optional required).
> >      type: boolean
> >  
> > +  host-wake-gpio:
> 
> There is only one wake signal in PCIe and it has a defined direction,
> so there is no point in specifying that it is a host wakeup. Also GPIO
> handles without a traling 's' are deprecated. So this should be
> 
> wake-gpios

Any standard PCI slot signals need to be documented in common PCI 
schema. And they should start going into root port nodes rather than the 
host bridge node because it's the root ports that correspond to slots 
rather than the host bridge. We've just taken shortcuts because many 
host bridges only have 1 root port.

Note that I'm in the middle of splitting pci-bus.yaml into host bridge, 
PCI-PCI bridge (and RP), and common device schemas.

Rob