Roadrunner technical documentation

ISC Image Sensor Controller (Camera)

Tested on Linux Kernel 5.15

Hardware used

Omnivision OV5640 camera

Wirings

Linux driver

Device Drivers  --->
    <*> Multimedia support  ---> 
        Media drivers  --->
            [*] V4L platform devices  --->
                <*>   ATMEL Image Sensor Controller (ISC) support
                <*>   ATMEL eXtended Image Sensor Controller (XISC) support
                <*>   ATMEL Image Sensor Interface (ISI) support
        Media ancillary drivers  --->
            <*> OmniVision OV5640 sensor support  

Device tree and defconfig

definitions inside apb section:

//********************
// Camera ISC Port
//********************

/* Omnivision OV5640 (5Mpixel) */

i2c1: i2c@fc028000 {
    #address-cells = <1>;
    #size-cells = <0>;
    pinctrl-names = "default","gpio";
    //pinctrl-names = "default";
    pinctrl-0 = <&pinctrl_i2c1_default>;
    pinctrl-1 = <&pinctrl_i2c1_gpio>;
    i2c-analog-filter;
    i2c-digital-filter;
    i2c-digital-filter-width-ns = <35>;
    sda-gpios = <&pioA PIN_PD4 GPIO_ACTIVE_HIGH>;
    scl-gpios = <&pioA PIN_PD5 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
    status = "okay";

    ov5640: camera@3c {
        compatible = "ovti,ov5640";
        reg = <0x3c>;
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_sensor_power &pinctrl_sensor_reset>;
        reset-gpios = <&pioA PIN_PB11 GPIO_ACTIVE_LOW>;
        powerdown-gpios = <&pioA PIN_PB12 GPIO_ACTIVE_HIGH>;
        clocks = <&isc>;
        clock-names = "xclk";
        assigned-clocks = <&isc>;
        assigned-clock-rates = <25000000>;
        status = "okay";

        port {
            ov5640_0: endpoint {
                remote-endpoint = <&isc_0>;
                bus-width = <8>;
                data-shift = <2>;
                hsync-active = <1>;
                vsync-active = <1>;
                pclk-sample = <1>;
            };
        };
    };

};


isc: isc@f0008000 {
    pinctrl-names = "default";
    pinctrl-0 = <&pinctrl_isc_base &pinctrl_isc_data_8bit>;
    status = "okay";

    port {
        isc_0: endpoint@0 {
            remote-endpoint = <&ov5640_0>;
            bus-width = <8>;
            data-shift = <2>;
            hsync-active = <0>;
            vsync-active = <0>;
            pclk-sample = <1>;
        };
    };
}; 

definitions inside pinctrl@fc038000 section:

pinctrl_isc_base: isc_base {
    pinmux = <PIN_PC4__ISC_PCK>,
         <PIN_PC5__ISC_VSYNC>,
         <PIN_PC6__ISC_HSYNC>,
         <PIN_PC7__ISC_MCK>;
    bias-disable;
};

pinctrl_isc_data_8bit: isc_data_8bit {
    pinmux = <PIN_PB25__ISC_D11>,
         <PIN_PB24__ISC_D10>,
         <PIN_PC3__ISC_D9>,
         <PIN_PC2__ISC_D8>,
         <PIN_PC1__ISC_D7>,
         <PIN_PC0__ISC_D6>,
         <PIN_PB31__ISC_D5>,
         <PIN_PB30__ISC_D4>;
    bias-disable;
};

pinctrl_sensor_power: sensor_power {
    pinmux = <PIN_PB12__GPIO>;
    bias-pull-up;
};

pinctrl_sensor_reset: sensor_reset {
    pinmux = <PIN_PB11__GPIO>;
    bias-pull-up;
};

Use the camera from user space

Test the v4l2 API compliance of the ISC driver

sudo v4l2-compliance

Display all information available

sudo v4l2-ctl --all

Use the Microchip script to capture

Configure the media controller pipeline

sudo media-ctl -d /dev/media0 --set-v4l2 '4:0[fmt:SRGGB8_1X8/1920x1080@1/30 field:none colorspace:srgb]'
sudo media-ctl -d /dev/media0 --set-v4l2 '"atmel_isc_scaler":0[fmt:SRGGB8_1X8/1920x1080 field:none colorspace:srgb]'
sudo v4l2-ctl -d /dev/video0 -v pixelformat=RGBP,height=1080,width=1920

Capture an image:

sudo fswebcam -d /dev/video0 -i 0 -p BAYER -r 1920x1080 /var/www/html/out.jpg

Links

• Linux4Sam: UsingISC (Image Sensor Controller)
• GitHub - Video Capture AT91
• Datasheet Omnivision OV5640
• 5MP: OV5640
• ov5640.dtso

Sergio Tanzilli
Systems designer, webmaster of www.acmesystems.it and founder of Acme Systems srl

Personal email: tanzilli@acmesystems.it
Web pages: https://www.acmesystems.it --- https://www.acmestudio.it
Github repositories: https://github.com/tanzilli --- https://github.com/acmesystems
Telegram group dedicated to the Acme Systems boards: https://t.me/acmesystemssrl

Roadrunner technical documentation