On 13/03/2020 14:40, Laurent Pinchart wrote: > Hi Phong, > > Thank you for the patch. > > On Wed, Mar 11, 2020 at 01:51:33PM +0100, Phong LE wrote: >> Add the ITE bridge HDMI it66121 bindings. >> >> Signed-off-by: Phong LE <ple@xxxxxxxxxxxx> >> --- >> .../bindings/display/bridge/ite,it66121.yaml | 98 +++++++++++++++++++ >> 1 file changed, 98 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/display/bridge/ite,it66121.yaml >> >> diff --git a/Documentation/devicetree/bindings/display/bridge/ite,it66121.yaml b/Documentation/devicetree/bindings/display/bridge/ite,it66121.yaml >> new file mode 100644 >> index 000000000000..1717e880d130 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/display/bridge/ite,it66121.yaml >> @@ -0,0 +1,98 @@ >> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) >> +%YAML 1.2 >> +--- >> +$id: http://devicetree.org/schemas/display/bridge/ite,it66121.yaml# >> +$schema: http://devicetree.org/meta-schemas/core.yaml# >> + >> +title: ITE it66121 HDMI bridge Device Tree Bindings >> + >> +maintainers: >> + - Phong LE <ple@xxxxxxxxxxxx> >> + - Neil Armstrong <narmstrong@xxxxxxxxxxxx> >> + >> +description: | >> + The IT66121 is a high-performance and low-power single channel HDMI >> + transmitter, fully compliant with HDMI 1.3a, HDCP 1.2 and backward compatible >> + to DVI 1.0 specifications. >> + >> +properties: >> + compatible: >> + const: ite,it66121 >> + >> + reg: >> + maxItems: 1 >> + description: base I2C address of the device >> + >> + reset-gpios: >> + maxItems: 1 >> + description: GPIO connected to active low reset >> + >> + vrf12-supply: >> + maxItems: 1 >> + description: Regulator for 1.2V analog core power. >> + >> + vcn33-supply: >> + maxItems: 1 >> + description: Regulator for 3.3V digital core power. >> + >> + vcn18-supply: >> + maxItems: 1 >> + description: Regulator for 1.8V IO core power. >> + >> + interrupts: >> + maxItems: 1 >> + >> + pclk-dual-edge: >> + maxItems: 1 >> + description: enable pclk dual edge mode. > > I'm having a bit of trouble understanding how this operates. Looking at > the driver code the property is only taken into account to calculate the > maximum allowed frequency. How is the IT66121 configured for single vs. > dual pixel clock edge mode ? Dual edge mode is Dual-Data-Rate mode, the normal mode is MEDIA_BUS_FMT_RGB888_1X24 and dual edge is MEDIA_BUS_FMT_RGB888_2X12_LE (or MEDIA_BUS_FMT_RGB888_2X12_BE, not sure) on a single clock period. This should be negociated at runtime, but the bus width should be specified somewhere to select one of the modes. Neil > >> + >> + port: >> + type: object >> + >> + properties: >> + endpoint: >> + type: object >> + description: | >> + Input endpoints of the bridge. >> + >> + required: >> + - endpoint > > You should have two ports, one for the bridge input, and one for the > bridge output. > >> + >> +required: >> + - compatible >> + - reg >> + - reset-gpios >> + - vrf12-supply >> + - vcn33-supply >> + - vcn18-supply >> + - interrupts >> + - port >> + >> +additionalProperties: false >> + >> +examples: >> + - | >> + i2c6 { >> + #address-cells = <1>; >> + #size-cells = <0>; >> + >> + it66121hdmitx: it66121hdmitx@4c { >> + compatible = "ite,it66121"; >> + pinctrl-names = "default"; >> + pinctrl-0 = <&ite_pins_default>; >> + vcn33-supply = <&mt6358_vcn33_wifi_reg>; >> + vcn18-supply = <&mt6358_vcn18_reg>; >> + vrf12-supply = <&mt6358_vrf12_reg>; >> + reset-gpios = <&pio 160 1 /* GPIO_ACTIVE_LOW */>; >> + interrupt-parent = <&pio>; >> + interrupts = <4 8 /* IRQ_TYPE_LEVEL_LOW */>; >> + reg = <0x4c>; >> + pclk-dual-edge; >> + >> + port { >> + it66121_in: endpoint { >> + remote-endpoint = <&display_out>; >> + }; >> + }; >> + }; >> + }; >
