| Message ID | 20240210070934.2549994-19-swboyd@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | platform/chrome: Add DT USB/DP muxing/topology to Trogdor | expand |
On 10/02/2024 08:09, Stephen Boyd wrote: > Describe the set of pins used to connect the detachable keyboard on > detachable ChromeOS devices. The set of pins is called the "pogo pins". > It's basically USB 2.0 with an extra pin for base detection. We expect > to find a keyboard on the other side of this connector with a specific > vid/pid, so describe that as a child device at the port of the usb > device connected upstream. > > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org> > Cc: Conor Dooley <conor+dt@kernel.org> > Cc: Benson Leung <bleung@chromium.org> > Cc: Guenter Roeck <groeck@chromium.org> > Cc: <devicetree@vger.kernel.org> > Cc: <chrome-platform@lists.linux.dev> > Cc: Pin-yen Lin <treapking@chromium.org> > Signed-off-by: Stephen Boyd <swboyd@chromium.org> > --- > .../chrome/google,pogo-pin-connector.yaml | 61 +++++++++++++++++++ > 1 file changed, 61 insertions(+) > create mode 100644 Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml > > diff --git a/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml b/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml > new file mode 100644 > index 000000000000..5ba68fd95fcd > --- /dev/null > +++ b/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml > @@ -0,0 +1,61 @@ > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/chrome/google,pogo-pin-connector.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Google Pogo Pin Connector > + > +maintainers: > + - Stephen Boyd <swboyd@chromium.org> > + Missing description describing the hardware. > +properties: > + compatible: > + const: google,pogo-pin-connector > + > + "#address-cells": > + const: 1 > + > + "#size-cells": > + const: 0 > + > + port: > + $ref: /schemas/graph.yaml#/properties/port > + description: Connection to USB2 port providing USB signals > + required: > + - endpoint Drop required. > + > +patternProperties: > + "^keyboard@[0-9a-f]{1,2}$": > + description: The detachable keyboard If this is detachable why do you define it in DT? Only hard-wired USB devices, which need some sort of special handling. are described in DT. > + type: object > + $ref: /schemas/usb/usb-device.yaml On this level: unevaluatedProperties: false > + > +required: > + - compatible > + - '#address-cells' > + - '#size-cells' Use one type of quotes, either ' or ". > + - port > + > +additionalProperties: false > + > +examples: > + - | > + connector { > + compatible = "google,pogo-pin-connector"; > + #address-cells = <1>; > + #size-cells = <0>; > + > + keyboard@2 { > + compatible = "usb18d1,504c"; Messed indentation. > + reg = <2>; > + }; > + Best regards, Krzysztof
Hi, On Fri, Feb 9, 2024 at 11:10 PM Stephen Boyd <swboyd@chromium.org> wrote: > > Describe the set of pins used to connect the detachable keyboard on > detachable ChromeOS devices. The set of pins is called the "pogo pins". > It's basically USB 2.0 with an extra pin for base detection. We expect > to find a keyboard on the other side of this connector with a specific > vid/pid, so describe that as a child device at the port of the usb > device connected upstream. Can you remind me what the side effects would be if a different VID/PID shows up there? I know it's not an end-user scenario, but I have a pre-production "coachz" keyboard that's actually programmed incorrectly and shows up as the wrong PID. Presumably I could either throw the old hardware away or figure out a way to re-program it and it's really not a big deal, but just curious what happens... -Doug
Quoting Krzysztof Kozlowski (2024-02-11 05:39:36) > On 10/02/2024 08:09, Stephen Boyd wrote: > > diff --git a/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml b/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml > > new file mode 100644 > > index 000000000000..5ba68fd95fcd > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml > > @@ -0,0 +1,61 @@ > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > +%YAML 1.2 > > +--- [...] > > > +properties: > > + compatible: > > + const: google,pogo-pin-connector > > + > > + "#address-cells": > > + const: 1 > > + > > + "#size-cells": > > + const: 0 > > + > > + port: > > + $ref: /schemas/graph.yaml#/properties/port > > + description: Connection to USB2 port providing USB signals > > + required: > > + - endpoint > > Drop required. Why? I'd like to make it so you can't have the node defined without connecting it up to the rest of the system. Is that bad? > > > > + > > +patternProperties: > > + "^keyboard@[0-9a-f]{1,2}$": > > + description: The detachable keyboard > > If this is detachable why do you define it in DT? Only hard-wired USB > devices, which need some sort of special handling. are described in DT. From the commit text: We expect to find a keyboard on the other side of this connector with a specific vid/pid, so describe that as a child device at the port of the usb device connected upstream. ChromeOS userspace is checking that the connected device downstream of this port has the expected vid/pid to quickly rule out USB keyboards that aren't the detachable keyboard. I wanted to express this in DT so that it didn't live in ChromeOS userspace forever.
Quoting Doug Anderson (2024-02-13 17:17:34) > Hi, > > On Fri, Feb 9, 2024 at 11:10 PM Stephen Boyd <swboyd@chromium.org> wrote: > > > > Describe the set of pins used to connect the detachable keyboard on > > detachable ChromeOS devices. The set of pins is called the "pogo pins". > > It's basically USB 2.0 with an extra pin for base detection. We expect > > to find a keyboard on the other side of this connector with a specific > > vid/pid, so describe that as a child device at the port of the usb > > device connected upstream. > > Can you remind me what the side effects would be if a different > VID/PID shows up there? I know it's not an end-user scenario, but I > have a pre-production "coachz" keyboard that's actually programmed > incorrectly and shows up as the wrong PID. Presumably I could either > throw the old hardware away or figure out a way to re-program it and > it's really not a big deal, but just curious what happens... As far as I know nothing happens besides ChromeOS userspace treats the keyboard as "external" so things like smarter base detection, e.g. wraparound keyboard detection or kickstand mode, may not work. I think you get a popup box telling you the keyboard isn't the trusted one.
On 15/02/2024 01:07, Stephen Boyd wrote: > Quoting Krzysztof Kozlowski (2024-02-11 05:39:36) >> On 10/02/2024 08:09, Stephen Boyd wrote: >>> diff --git a/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml b/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml >>> new file mode 100644 >>> index 000000000000..5ba68fd95fcd >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml >>> @@ -0,0 +1,61 @@ >>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) >>> +%YAML 1.2 >>> +--- > [...] >> >>> +properties: >>> + compatible: >>> + const: google,pogo-pin-connector >>> + >>> + "#address-cells": >>> + const: 1 >>> + >>> + "#size-cells": >>> + const: 0 >>> + >>> + port: >>> + $ref: /schemas/graph.yaml#/properties/port >>> + description: Connection to USB2 port providing USB signals >>> + required: >>> + - endpoint >> >> Drop required. > > Why? I'd like to make it so you can't have the node defined without > connecting it up to the rest of the system. Is that bad? Hm, I double checked and you're right. I thought endpoint is required anyway by graph.yaml in dtschema, but it seems it is not. > >> >> >>> + >>> +patternProperties: >>> + "^keyboard@[0-9a-f]{1,2}$": >>> + description: The detachable keyboard >> >> If this is detachable why do you define it in DT? Only hard-wired USB >> devices, which need some sort of special handling. are described in DT. > > From the commit text: > > We expect to find a keyboard on the other side of this connector with a > specific vid/pid, so describe that as a child device at the port of the > usb device connected upstream. > > ChromeOS userspace is checking that the connected device downstream of > this port has the expected vid/pid to quickly rule out USB keyboards > that aren't the detachable keyboard. I wanted to express this in DT so > that it didn't live in ChromeOS userspace forever. OK, Best regards, Krzysztof
diff --git a/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml b/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml new file mode 100644 index 000000000000..5ba68fd95fcd --- /dev/null +++ b/Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml @@ -0,0 +1,61 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/chrome/google,pogo-pin-connector.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Google Pogo Pin Connector + +maintainers: + - Stephen Boyd <swboyd@chromium.org> + +properties: + compatible: + const: google,pogo-pin-connector + + "#address-cells": + const: 1 + + "#size-cells": + const: 0 + + port: + $ref: /schemas/graph.yaml#/properties/port + description: Connection to USB2 port providing USB signals + required: + - endpoint + +patternProperties: + "^keyboard@[0-9a-f]{1,2}$": + description: The detachable keyboard + type: object + $ref: /schemas/usb/usb-device.yaml + +required: + - compatible + - '#address-cells' + - '#size-cells' + - port + +additionalProperties: false + +examples: + - | + connector { + compatible = "google,pogo-pin-connector"; + #address-cells = <1>; + #size-cells = <0>; + + keyboard@2 { + compatible = "usb18d1,504c"; + reg = <2>; + }; + + port { + pogo_connector_in: endpoint { + remote-endpoint = <&usb_hub_dsp3_hs>; + }; + }; + }; + +...
Describe the set of pins used to connect the detachable keyboard on detachable ChromeOS devices. The set of pins is called the "pogo pins". It's basically USB 2.0 with an extra pin for base detection. We expect to find a keyboard on the other side of this connector with a specific vid/pid, so describe that as a child device at the port of the usb device connected upstream. Cc: Rob Herring <robh+dt@kernel.org> Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org> Cc: Conor Dooley <conor+dt@kernel.org> Cc: Benson Leung <bleung@chromium.org> Cc: Guenter Roeck <groeck@chromium.org> Cc: <devicetree@vger.kernel.org> Cc: <chrome-platform@lists.linux.dev> Cc: Pin-yen Lin <treapking@chromium.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> --- .../chrome/google,pogo-pin-connector.yaml | 61 +++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100644 Documentation/devicetree/bindings/chrome/google,pogo-pin-connector.yaml