Re: [PATCH RESEND 3/4] dt-bindings: drm/bridge: Add GPIO display mux binding
On Fri, Dec 20, 2019 at 4:48 AM Rob Herring 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 wrote: > > > > > > On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang wrote: > > > > > > > > From: Nicolas Boichat > > > > > > > > Add bindings for Generic GPIO mux driver. > > > > > > > > Signed-off-by: Nicolas Boichat > > > > Signed-off-by: Hsin-Yi Wang > > > > --- > > > > 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 ..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-hoxangooyfoyj3...@mail.gmail.com/), they would need such driver. But currently we only know that mt8173 oak board have this use case. > > Rob ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
Re: [PATCH RESEND 3/4] dt-bindings: drm/bridge: Add GPIO display mux binding
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 wrote: > > > > On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang wrote: > > > > > > From: Nicolas Boichat > > > > > > Add bindings for Generic GPIO mux driver. > > > > > > Signed-off-by: Nicolas Boichat > > > Signed-off-by: Hsin-Yi Wang > > > --- > > > 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 ..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 ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
Re: [PATCH RESEND 3/4] dt-bindings: drm/bridge: Add GPIO display mux binding
On Sat, Dec 14, 2019 at 5:29 AM Rob Herring wrote:
>
> On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang wrote:
> >
> > From: Nicolas Boichat
> >
> > Add bindings for Generic GPIO mux driver.
> >
> > Signed-off-by: Nicolas Boichat
> > Signed-off-by: Hsin-Yi Wang
> > ---
> > 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 ..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
> > +
> > +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 = < 36 GPIO_ACTIVE_HIGH>;
> > + pinctrl-names = "default";
> > + pinctrl-0 = <_mux_pins>;
> > + ddc-i2c-bus = <>;
>
> 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 = <_out>;
> > + };
> > +};
> > +
> > +port@1 { /* output */
> > + reg = <1>;
> > +
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + hdmi_mux_out_anx: endpoint@0 {
> > +reg = <0>;
> > +remote-endpoint = <_in>;
> > + };
> > +
> > + hdmi_mux_out_hdmi: endpoint@1 {
> > +reg = <1>;
> > +remote-endpoint = <_connector_in>;
> > + };
> > +};
> > + };
> > +};
> > --
> > 2.24.0.525.g8f36a354ae-goog
> >
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Re: [PATCH RESEND 3/4] dt-bindings: drm/bridge: Add GPIO display mux binding
On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang wrote:
>
> From: Nicolas Boichat
>
> Add bindings for Generic GPIO mux driver.
>
> Signed-off-by: Nicolas Boichat
> Signed-off-by: Hsin-Yi Wang
> ---
> 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 ..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
> +
> +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 = < 36 GPIO_ACTIVE_HIGH>;
> + pinctrl-names = "default";
> + pinctrl-0 = <_mux_pins>;
> + ddc-i2c-bus = <>;
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 = <_out>;
> + };
> +};
> +
> +port@1 { /* output */
> + reg = <1>;
> +
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + hdmi_mux_out_anx: endpoint@0 {
> +reg = <0>;
> +remote-endpoint = <_in>;
> + };
> +
> + hdmi_mux_out_hdmi: endpoint@1 {
> +reg = <1>;
> +remote-endpoint = <_connector_in>;
> + };
> +};
> + };
> +};
> --
> 2.24.0.525.g8f36a354ae-goog
>
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[PATCH RESEND 3/4] dt-bindings: drm/bridge: Add GPIO display mux binding
From: Nicolas Boichat
Add bindings for Generic GPIO mux driver.
Signed-off-by: Nicolas Boichat
Signed-off-by: Hsin-Yi Wang
---
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 ..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
+
+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 = < 36 GPIO_ACTIVE_HIGH>;
+ pinctrl-names = "default";
+ pinctrl-0 = <_mux_pins>;
+ ddc-i2c-bus = <>;
+
+ ports {
+#address-cells = <1>;
+#size-cells = <0>;
+
+port@0 { /* input */
+ reg = <0>;
+
+ hdmi_mux_in: endpoint {
+remote-endpoint = <_out>;
+ };
+};
+
+port@1 { /* output */
+ reg = <1>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ hdmi_mux_out_anx: endpoint@0 {
+reg = <0>;
+remote-endpoint = <_in>;
+ };
+
+ hdmi_mux_out_hdmi: endpoint@1 {
+reg = <1>;
+remote-endpoint = <_connector_in>;
+ };
+};
+ };
+};
--
2.24.0.525.g8f36a354ae-goog
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