| Message ID | 20191211061911.238393-4-hsinyi@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: bridge: anx7688 and mux drivers | expand |
On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang <hsinyi@chromium.org> wrote: > > From: Nicolas Boichat <drinkcat@chromium.org> > > Add bindings for Generic GPIO mux driver. > > Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> > Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> > --- > Change from RFC to v1: > - txt to yaml > --- > .../bindings/display/bridge/gpio-mux.yaml | 89 +++++++++++++++++++ > 1 file changed, 89 insertions(+) > create mode 100644 Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > diff --git a/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > new file mode 100644 > index 000000000000..cef098749066 > --- /dev/null > +++ b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > @@ -0,0 +1,89 @@ > +# SPDX-License-Identifier: GPL-2.0 > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/display/bridge/gpio-mux.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Generic display mux (1 input, 2 outputs) What makes it generic? Doesn't the mux chip have power supply, possibly a reset line or not, etc.? What about a mux where the GPIO controls the mux? Generally, we avoid 'generic' bindings because h/w is rarely generic. You can have a generic driver which works on multiple devices. > + > +maintainers: > + - Nicolas Boichat <drinkcat@chromium.org> > + > +description: | > + This bindings describes a simple display (e.g. HDMI) mux, that has 1 > + input, and 2 outputs. The mux status is controlled by hardware, and > + its status is read back using a GPIO. > + > +properties: > + compatible: > + const: gpio-display-mux > + > + detect-gpios: > + maxItems: 1 > + description: GPIO that indicates the active output > + > + ports: > + type: object > + > + properties: > + port@0: > + type: object > + description: | > + Video port for input. > + > + port@1: > + type: object > + description: | > + 2 video ports for output. > + The reg value in the endpoints matches the GPIO status: when > + GPIO is asserted, endpoint with reg value <1> is selected. You should describe 'endpoint@0' and 'endpoint@1' here too. > + > + required: > + - port@0 > + - port@1 > + > +required: > + - compatible > + - detect-gpios > + - ports > + > +examples: > + - | > + hdmi_mux: hdmi_mux { > + compatible = "gpio-display-mux"; > + status = "okay"; Don't show status in examples. > + detect-gpios = <&pio 36 GPIO_ACTIVE_HIGH>; > + pinctrl-names = "default"; > + pinctrl-0 = <&hdmi_mux_pins>; > + ddc-i2c-bus = <&hdmiddc0>; Not documented. Is the i2c bus muxed too? If not, then this is in the wrong place. > + > + ports { > + #address-cells = <1>; > + #size-cells = <0>; > + > + port@0 { /* input */ > + reg = <0>; > + > + hdmi_mux_in: endpoint { > + remote-endpoint = <&hdmi0_out>; > + }; > + }; > + > + port@1 { /* output */ > + reg = <1>; > + > + #address-cells = <1>; > + #size-cells = <0>; > + > + hdmi_mux_out_anx: endpoint@0 { > + reg = <0>; > + remote-endpoint = <&anx7688_in>; > + }; > + > + hdmi_mux_out_hdmi: endpoint@1 { > + reg = <1>; > + remote-endpoint = <&hdmi_connector_in>; > + }; > + }; > + }; > + }; > -- > 2.24.0.525.g8f36a354ae-goog >
On Sat, Dec 14, 2019 at 5:29 AM Rob Herring <robh+dt@kernel.org> wrote: > > On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang <hsinyi@chromium.org> wrote: > > > > From: Nicolas Boichat <drinkcat@chromium.org> > > > > Add bindings for Generic GPIO mux driver. > > > > Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> > > Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> > > --- > > Change from RFC to v1: > > - txt to yaml > > --- > > .../bindings/display/bridge/gpio-mux.yaml | 89 +++++++++++++++++++ > > 1 file changed, 89 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > > > diff --git a/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > new file mode 100644 > > index 000000000000..cef098749066 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > @@ -0,0 +1,89 @@ > > +# SPDX-License-Identifier: GPL-2.0 > > +%YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/display/bridge/gpio-mux.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: Generic display mux (1 input, 2 outputs) > > What makes it generic? Doesn't the mux chip have power supply, > possibly a reset line or not, etc.? What about a mux where the GPIO > controls the mux? > > Generally, we avoid 'generic' bindings because h/w is rarely generic. > You can have a generic driver which works on multiple devices. > Then how about making it mt8173-oak-gpio-mux? Since this is currently only used in this board. > > + > > +maintainers: > > + - Nicolas Boichat <drinkcat@chromium.org> > > + > > +description: | > > + This bindings describes a simple display (e.g. HDMI) mux, that has 1 > > + input, and 2 outputs. The mux status is controlled by hardware, and > > + its status is read back using a GPIO. > > + > > +properties: > > + compatible: > > + const: gpio-display-mux > > + > > + detect-gpios: > > + maxItems: 1 > > + description: GPIO that indicates the active output > > + > > + ports: > > + type: object > > + > > + properties: > > + port@0: > > + type: object > > + description: | > > + Video port for input. > > + > > + port@1: > > + type: object > > + description: | > > + 2 video ports for output. > > + The reg value in the endpoints matches the GPIO status: when > > + GPIO is asserted, endpoint with reg value <1> is selected. > > You should describe 'endpoint@0' and 'endpoint@1' here too. Will add in next version, thanks > > > + > > + required: > > + - port@0 > > + - port@1 > > + > > +required: > > + - compatible > > + - detect-gpios > > + - ports > > + > > +examples: > > + - | > > + hdmi_mux: hdmi_mux { > > + compatible = "gpio-display-mux"; > > + status = "okay"; > > Don't show status in examples. > > > + detect-gpios = <&pio 36 GPIO_ACTIVE_HIGH>; > > + pinctrl-names = "default"; > > + pinctrl-0 = <&hdmi_mux_pins>; > > + ddc-i2c-bus = <&hdmiddc0>; > > Not documented. Is the i2c bus muxed too? If not, then this is in the > wrong place. > It's muxed, but this is required because of [1], so it should be removed in this example. [1]https://elixir.bootlin.com/linux/v5.5-rc2/source/Documentation/devicetree/bindings/display/mediatek/mediatek,hdmi.txt#L24 > > + > > + ports { > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + port@0 { /* input */ > > + reg = <0>; > > + > > + hdmi_mux_in: endpoint { > > + remote-endpoint = <&hdmi0_out>; > > + }; > > + }; > > + > > + port@1 { /* output */ > > + reg = <1>; > > + > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + hdmi_mux_out_anx: endpoint@0 { > > + reg = <0>; > > + remote-endpoint = <&anx7688_in>; > > + }; > > + > > + hdmi_mux_out_hdmi: endpoint@1 { > > + reg = <1>; > > + remote-endpoint = <&hdmi_connector_in>; > > + }; > > + }; > > + }; > > + }; > > -- > > 2.24.0.525.g8f36a354ae-goog > >
On Mon, Dec 16, 2019 at 03:16:23PM +0800, Hsin-Yi Wang wrote: > On Sat, Dec 14, 2019 at 5:29 AM Rob Herring <robh+dt@kernel.org> wrote: > > > > On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang <hsinyi@chromium.org> wrote: > > > > > > From: Nicolas Boichat <drinkcat@chromium.org> > > > > > > Add bindings for Generic GPIO mux driver. > > > > > > Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> > > > Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> > > > --- > > > Change from RFC to v1: > > > - txt to yaml > > > --- > > > .../bindings/display/bridge/gpio-mux.yaml | 89 +++++++++++++++++++ > > > 1 file changed, 89 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > > > > > diff --git a/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > > new file mode 100644 > > > index 000000000000..cef098749066 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > > @@ -0,0 +1,89 @@ > > > +# SPDX-License-Identifier: GPL-2.0 > > > +%YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/display/bridge/gpio-mux.yaml# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > + > > > +title: Generic display mux (1 input, 2 outputs) > > > > What makes it generic? Doesn't the mux chip have power supply, > > possibly a reset line or not, etc.? What about a mux where the GPIO > > controls the mux? > > > > Generally, we avoid 'generic' bindings because h/w is rarely generic. > > You can have a generic driver which works on multiple devices. > > > Then how about making it mt8173-oak-gpio-mux? Since this is currently > only used in this board. Isn't there an underlying part# you can use? Or if you can point me to multiple chips implementing the same thing, then maybe a generic binding is fine. Rob
On Fri, Dec 20, 2019 at 4:48 AM Rob Herring <robh@kernel.org> wrote: > > On Mon, Dec 16, 2019 at 03:16:23PM +0800, Hsin-Yi Wang wrote: > > On Sat, Dec 14, 2019 at 5:29 AM Rob Herring <robh+dt@kernel.org> wrote: > > > > > > On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang <hsinyi@chromium.org> wrote: > > > > > > > > From: Nicolas Boichat <drinkcat@chromium.org> > > > > > > > > Add bindings for Generic GPIO mux driver. > > > > > > > > Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> > > > > Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> > > > > --- > > > > Change from RFC to v1: > > > > - txt to yaml > > > > --- > > > > .../bindings/display/bridge/gpio-mux.yaml | 89 +++++++++++++++++++ > > > > 1 file changed, 89 insertions(+) > > > > create mode 100644 Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > > > > > > > diff --git a/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > > > new file mode 100644 > > > > index 000000000000..cef098749066 > > > > --- /dev/null > > > > +++ b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml > > > > @@ -0,0 +1,89 @@ > > > > +# SPDX-License-Identifier: GPL-2.0 > > > > +%YAML 1.2 > > > > +--- > > > > +$id: http://devicetree.org/schemas/display/bridge/gpio-mux.yaml# > > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > > + > > > > +title: Generic display mux (1 input, 2 outputs) > > > > > > What makes it generic? Doesn't the mux chip have power supply, > > > possibly a reset line or not, etc.? What about a mux where the GPIO > > > controls the mux? > > > > > > Generally, we avoid 'generic' bindings because h/w is rarely generic. > > > You can have a generic driver which works on multiple devices. > > > > > Then how about making it mt8173-oak-gpio-mux? Since this is currently > > only used in this board. > > Isn't there an underlying part# you can use? Or if you can point me to > multiple chips implementing the same thing, then maybe a generic binding > is fine. There are some similar chips, for example: https://www.paradetech.com/zh-hant/%E7%94%A2%E5%93%81%E4%BB%8B%E7%B4%B9/ps8223-3-0gbps-hdmi-12-demultiplexer/ and http://www.ti.com/lit/ds/symlink/ts3dv642.pdf If they are used in a similar way (https://lore.kernel.org/lkml/CANMq1KDDEzPWhByEtn-EjNcg+ofVT2MW-hOXANGooYFOYJ35VA@mail.gmail.com/), they would need such driver. But currently we only know that mt8173 oak board have this use case. > > Rob
diff --git a/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml new file mode 100644 index 000000000000..cef098749066 --- /dev/null +++ b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml @@ -0,0 +1,89 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/display/bridge/gpio-mux.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic display mux (1 input, 2 outputs) + +maintainers: + - Nicolas Boichat <drinkcat@chromium.org> + +description: | + This bindings describes a simple display (e.g. HDMI) mux, that has 1 + input, and 2 outputs. The mux status is controlled by hardware, and + its status is read back using a GPIO. + +properties: + compatible: + const: gpio-display-mux + + detect-gpios: + maxItems: 1 + description: GPIO that indicates the active output + + ports: + type: object + + properties: + port@0: + type: object + description: | + Video port for input. + + port@1: + type: object + description: | + 2 video ports for output. + The reg value in the endpoints matches the GPIO status: when + GPIO is asserted, endpoint with reg value <1> is selected. + + required: + - port@0 + - port@1 + +required: + - compatible + - detect-gpios + - ports + +examples: + - | + hdmi_mux: hdmi_mux { + compatible = "gpio-display-mux"; + status = "okay"; + detect-gpios = <&pio 36 GPIO_ACTIVE_HIGH>; + pinctrl-names = "default"; + pinctrl-0 = <&hdmi_mux_pins>; + ddc-i2c-bus = <&hdmiddc0>; + + ports { + #address-cells = <1>; + #size-cells = <0>; + + port@0 { /* input */ + reg = <0>; + + hdmi_mux_in: endpoint { + remote-endpoint = <&hdmi0_out>; + }; + }; + + port@1 { /* output */ + reg = <1>; + + #address-cells = <1>; + #size-cells = <0>; + + hdmi_mux_out_anx: endpoint@0 { + reg = <0>; + remote-endpoint = <&anx7688_in>; + }; + + hdmi_mux_out_hdmi: endpoint@1 { + reg = <1>; + remote-endpoint = <&hdmi_connector_in>; + }; + }; + }; + };