ADV7511

ADV7511 HDMI transmitter Linux Driver.

Supported Devices

Evaluation Boards

Reference Circuits

Description

The ADV7511 driver is implemented as a DRM bridge driver. In a typical board design the ADV7511 is not used as a standalone component but rather as a HDMI encoder fronted for some other devices with a graphics core, like a SoC or a FPGA. Implementing the ADV7511 driver as a DRM bridge driver allows to reuse the driver between different platforms which use the ADV7511.

For an example implementation of a DRM driver using the ADV7511 please refer to Linux driver for the Analog Devices example HDL design for the Xilinx Zync plus ADV7511 designs.

The driver supports audio via HDMI as well by implementing a ASoC codec driver. This again allows to reuse the driver for a varieties of different platforms.

Source Code

Status

Source

Mainlined?

git

Yes

Files

Function

File

driver

drivers/gpu/drm/bridge/adv7511/adv7511_drv.c

driver

drivers/gpu/drm/bridge/adv7511/adv7511_audio.c

driver

drivers/gpu/drm/bridge/adv7511/adv7533.c

include

drivers/gpu/drm/bridge/adv7511/adv7511.h

Adding Linux driver support

Kernel configuration

Configure kernel with make menuconfig (alternatively use make xconfig or make qconfig)

Note

The ADV7511 Driver depends on CONFIG_DRM and CONFIG_I2C

Linux Kernel Configuration
    Device Drivers  --->
        Graphics support  --->
            <*> Direct Rendering Manager (XFree86 4.1.0 and higher DRI support)  --->
            ...
            <*> AV7511 encoder

Devicetree configuration

Example platform device initialization

DRM

Instantiate ADV7511, ADV7511W or ADV7513 as an I2C device in Device Tree, and connect its input graph endpoint to the upstream display controller. Configure the physical bus with adi,input-depth, adi,input-colorspace and adi,input-clock. For YUV422 input, or a clock mode other than 1x, also specify adi,input-style and adi,input-justification. adi,clock-delay is in picoseconds; adi,embedded-sync selects embedded synchronization when the hardware uses it.

The adi,input-clock values are 1x (one clock cycle per pixel), 2x (two clock cycles per pixel) and ddr (data driven on both clock edges).

The DRM bridge configures output conversion and HDMI/DVI operation as part of mode setting. It does not use the old adv7511_video_input_config structure or encoder-slave set_config callback. ADV7533 and ADV7535 have a separate DSI configuration path.

The following fragment declares the transmitter, its supplies and the video graph. Include it together with the input-bus configuration in the next section; both fragments are needed for the complete example.

The board must already define i2c0 (the actual I2C bus or mux channel), display_out (the upstream video endpoint), and v1v8/v3v3 (the supplies connected to the transmitter pins). The labels, I2C address, and connector type are board-specific. The input endpoint must link back to adv7511_in, as shown. Configure the display controller and its clocks/pin multiplexing in its own board node.

/* Board supplies and the display controller endpoint are defined elsewhere. */
&i2c0 {
    #address-cells = <1>;
    #size-cells = <0>;
    status = "okay";

    adv7511: hdmi@39 {
        compatible = "adi,adv7511";
        reg = <0x39>;

        avdd-supply = <&v1v8>;
        dvdd-supply = <&v1v8>;
        pvdd-supply = <&v1v8>;
        dvdd-3v-supply = <&v3v3>;
        bgvdd-supply = <&v1v8>;

        ports {
            #address-cells = <1>;
            #size-cells = <0>;

            port@0 {
                reg = <0>;
                adv7511_in: endpoint {
                    remote-endpoint = <&display_out>;
                };
            };

            port@1 {
                reg = <1>;
                adv7511_out: endpoint {
                    remote-endpoint = <&hdmi_connector_in>;
                };
            };
        };
    };
};

&display_out {
    remote-endpoint = <&adv7511_in>;
};

/ {
    hdmi-connector {
        compatible = "hdmi-connector";
        type = "a";

        port {
            hdmi_connector_in: endpoint {
                remote-endpoint = <&adv7511_out>;
            };
        };
    };
};
Example Configuration

This fragment configures the adv7511 node declared above for 8-bit-component YUV422, input style 1, right justification, a 1x input clock and separate sync signals. Include it after the declaration in the same board Device Tree. Use these physical bus settings only when they match the upstream display controller and board wiring.

&adv7511 {
    adi,input-depth = <8>;
    adi,input-colorspace = "yuv422";
    adi,input-clock = "1x";
    adi,input-style = <1>;
    adi,input-justification = "right";
    adi,clock-delay = <0>;
};

Only the main I2C address is set here; the other register pages use their default addresses. If the board changes those addresses, specify the extra reg entries with the binding’s reg-names. Add board-specific interrupt and power-down GPIO properties when applicable. This fragment shows the video path; audio needs its own sound-card integration.

ASoC
DAI configuration

With CONFIG_DRM_I2C_ADV7511_AUDIO enabled, the driver creates an hdmi-audio-codec child. The generic HDMI codec registers i2s-hifi and spdif-hifi DAIs; ADV7511 configures a maximum of two I2S channels. Link the sound card to the appropriate child DAI, not adau-hifi or adv7511.

Supported DAI formats

Name

Supported by driver

Description

SND_SOC_DAIFMT_I2S

yes

I2S mode

SND_SOC_DAIFMT_RIGHT_J

yes

Right Justified mode

SND_SOC_DAIFMT_LEFT_J

yes

Left Justified mode

SND_SOC_DAIFMT_DSP_A

no

data MSB after FRM LRC

SND_SOC_DAIFMT_DSP_B

no

data MSB during FRM LRC

SND_SOC_DAIFMT_AC97

no

AC97 mode

SND_SOC_DAIFMT_PDM

no

Pulse density modulation

SND_SOC_DAIFMT_SPDIF

yes

SPDIF

The ADV7511 audio callback programs bit-clock inversion from bit_clk_inv. It does not configure frame-clock inversion or bit/frame-clock provider flags.

Example DAI configuration

Select the actual registered hdmi-audio-codec child component and its spdif-hifi DAI for SPDIF, or i2s-hifi for I2S. The component’s automatic instance number is not fixed by the I2C address. In the partial SPDIF link below, N is the registered child instance number; supply the CPU and platform component arrays from the machine driver. It is not a complete board registration example.

static struct snd_soc_dai_link_component hdmi_codecs[] = {
    {
        .name = "hdmi-audio-codec.N.auto",
        .dai_name = "spdif-hifi",
    },
};

static struct snd_soc_dai_link hdmi_dai_link = {
    .name = "HDMI",
    .stream_name = "HDMI",
    .codecs = hdmi_codecs,
    .num_codecs = ARRAY_SIZE(hdmi_codecs),
    .dai_fmt = SND_SOC_DAIFMT_SPDIF |
               SND_SOC_DAIFMT_NB_NF |
               SND_SOC_DAIFMT_CBC_CFC,
};

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