MIPI CSI 使用

简介

AIO-3399ProC 开发板分别带有两个MIPI，MIPI最高支持支持4K拍照，并支持
1080P 30FPS以上视频录制。此外，开发板还支持 USB 摄像头。

本文以 OV13850 摄像头为例，讲解在该开发板上的配置过程。

接口效果图


DTS配置

   isp0: isp@ff910000 {
       …
       status = "okay";
   }
   isp1: isp@ff920000 {
       …
       status = "okay";
   }

驱动说明

与摄像头相关的代码目录如下：

   hal3_camera :
   ├── AAL Android Abstraction Layer负责与 framework 交互
   ├── common 公用文件,如线程,消息处理,Log 打印等实现
   │ ├── gcss xml 解析相关
   │ ├── imageProcess 图像处理相关,如 scale
   │ ├── jpeg jpeg 编码相关
   │ ├── mediacontroller media pipeline 相关
   │ ├── platformdata hal3 能力支持的属性,主要是管理从 xml 获取到的属性
   │ ├── utils 目前只有一个 Error.h,定义了一些返回值
   │ └── v4l2dev 封装了一些与 v4l2 驱动交互的具体 io
   ├── etc 配置文件目录
   ├── include Control loop 的头文件,buffer_manager 相关头文件
   ├── lib 3a engine 相关库
   ├── psl Physical Layer,物理实现层,所有的实现逻辑基本都在这里
   │ └── rkisp1 目前只有 Rkisp1 一套实现方案
   │ ├── tasks 基本只用到了里面的几个 Notify 的接口类和 JpegEncodeTask
   │ └── workers 数据的获取处理都在这里
   └── tools 包含了一个自动生成 graph setting xml 的 Python 脚本

   Linux Kernel-4.4:|
   |-- arch/arm64/boot/dts/rockchip DTS 配置文件
   |-- drivers/phy/rockchip/  mipi dphy 驱动
   	|-- phy-rockchip-mipi-rx.c
   |-- drivers/media|
    |-- platform/rockchip/isp1 rkisp1 isp 驱动
     |-- capture.c  包含 mp/sp 的配置及 vb2,帧中断处理
     |-- dev.c 	 包含 probe、异步注册、clock、pipeline、iommu 及 media/v4l2 framework
     |-- isp_params.c 3A 相关参数设置
     |-- isp_stats.c 3A 相关统计
     |-- regs.c 寄存器相关的读写操作
     |-- rkisp1.c 对应 isp_sd entity 节点,包含从 mipi 接收数据,并有 crop 功能
    |-- i2c/
     |-- ov13850.c CIS(cmos image sensor)驱动
     |-- vm149c.c VCM driver ic 驱动
    |-- spi/ rk1608 ap driver 驱动
     |-- rk1608.c 注册 rk1608 spi 设备
     |-- rk1608_dev.c 注册/dev/rk_preisp misc 设备
     |-- rk1608_dphy.c 注册 v4l2 media 节点,与 rk1608 和 AP 端交互

配置原理

设置摄像头相关的引脚和时钟，即可完成配置过程。 从以下摄像头接口原理图
可知，需要配置的引脚有：MIPI_PWR, MIPI_PDN0_CAM/MIPI_PDN1_CAM和
RST_CAM_0/1。

mipi接口

MIPI_PWR 对应 RK3399Pro 的 GPIO3_D5;

MIPI_PDN0_CAM/MIPI_PDN1_CAM 对应 RK3399Pro 的 GPIO3_D3 / GPIO3_D4;

MIPI_RST0/MIPI_RST1 对应GPIO2_A6 / GPIO2_A1;

在开发板中，这三个引脚都是在 kernel/arch/arm64/boot/dts/rockchip
/rk3399pro-firefly-usbacm.dtsi 中设置。

配置步骤

配置 ov13850驱动和VCM驱动

修改kernel/arch/arm64/boot/dts/rockchip/rk3399pro-firefly-usbacm.dtsi
初始化摄像头：

   {
           vcc_mipi: vcc_mipi {
                   compatible = "regulator-fixed";
                   enable-active-high;
                   gpio = <&gpio3 29 GPIO_ACTIVE_HIGH>;
                   pinctrl-names = "default";
                   pinctrl-0 = <&dvp_pwr>;
                   regulator-name = "vcc_mipi";
           };
   };
   .....
   &i2c1 {
           vm149c: vm149c@0c {
                   compatible = "silicon touch,vm149c";
                   status = "okay";
                   reg = <0x0c>;
                   rockchip,camera-module-index = <0>;
                   rockchip,camera-module-facing = "back";
           };

           ov13850b: ov13850b@10 {
                   compatible = "ovti,ov13850";
                   reg = <0x10>;
                   clocks = <&cru SCLK_CIF_OUT>;
                   clock-names = "xvclk";
                   avdd-supply = <&vcc_mipi>;
                   /* dvdd-supply = <>; */
                   /* dovdd-supply = <>; */
                   /* reset-gpios = <>; */
                   //mipi-pwr-gpios = <&gpio3 29 GPIO_ACTIVE_HIGH>;
                   reset-gpios = <&gpio2 6 GPIO_ACTIVE_HIGH>;
                   pwdn-gpios = <&gpio3 27 GPIO_ACTIVE_HIGH>;
                   //pinctrl-names = "rockchip,camera_default", "rockchip,camera_sleep";
                   //pinctrl-0 = <&cam0_default_pins>;
                   //pinctrl-1 = <&cam0_sleep_pins>;
                   pinctrl-names = "rockchip,camera_default";
                   pinctrl-0 = <&cif_clkout>;

                   firefly,clkout-enabled-index = <0>;
                   rockchip,camera-module-index = <0>;
                   rockchip,camera-module-facing = "back";
                   rockchip,camera-module-name = "CMK-CT0116";
                   rockchip,camera-module-lens-name = "Largan-50013A1";
                   lens-focus = <&vm149c>;

                   port {
                           ucam_out0: endpoint {
                                   remote-endpoint = <&mipi_in_ucam0>;
                                   data-lanes = <1 2>;
                           };
                   };
           };
           vm149c_front: vm149c_front@0c {
                   compatible = "silicon touch,vm149c";
                   status = "okay";
                   reg = <0x0c>;
                   rockchip,camera-module-index = <1>;
                   rockchip,camera-module-facing = "front";
           };

           ov13850f: ov13850f@10 {
                   compatible = "ovti,ov13850";
                   reg = <0x10>;
                   clocks = <&cru SCLK_CIF_OUT>;
                   clock-names = "xvclk";
                   avdd-supply = <&vcc_mipi>;
                   //mipi-pwr-gpios = <&gpio3 29 GPIO_ACTIVE_HIGH>;
                   reset-gpios = <&gpio2 1 GPIO_ACTIVE_HIGH>;
                   pwdn-gpios = <&gpio3 28 GPIO_ACTIVE_HIGH>;
                   //pinctrl-names = "rockchip,camera_default", "rockchip,camera_sleep";
                   //pinctrl-0 = <&cam0_default_pins>;
                   //pinctrl-1 = <&cam0_sleep_pins>;
                   pinctrl-names = "rockchip,camera_default";
                   pinctrl-0 = <&cif_clkout>;

                   firefly,second-enabled-index = <1>;
                   firefly,clkout-enabled-index = <0>;
                   rockchip,camera-module-index = <1>;
                   rockchip,camera-module-facing = "front";
                   rockchip,camera-module-name = "CMK-CT0116";
                   rockchip,camera-module-lens-name = "Largan-50013A1";
                   lens-focus = <&vm149c_front>;

                   port {
                           ucam_out1: endpoint {
                                   remote-endpoint = <&mipi_in_ucam1>;
                                   data-lanes = <1 2>;
                           };
                   };
           };
   };

   &pinctrl {
           cam0 {
                   dvp_pwr: dvp-pwr {
                           rockchip,pins = <3 29 RK_FUNC_GPIO &pcfg_pull_up>;
                   };
           };
   };

修改ov13850驱动上电时序 kernel/drivers/media/i2c/ov13850.c

   +static int __ov13850_power_on(struct ov13850 *ov13850);
   +static void __ov13850_power_off(struct ov13850 *ov13850);
    static int ov13850_s_power(struct v4l2_subdev *sd, int on)
    {
           struct ov13850 *ov13850 = to_ov13850(sd);
   @@ -1055,6 +1058,7 @@ static int ov13850_s_power(struct v4l2_subdev *sd, int on)
                           goto unlock_and_return;
                   }

   +               __ov13850_power_on(ov13850);
                   ret = ov13850_write_array(ov13850->client, ov13850_global_regs);
                   if (ret) {
                           v4l2_err(sd, "could not set init registers\n");
   @@ -1063,9 +1067,20 @@ static int ov13850_s_power(struct v4l2_subdev *sd, int on)
                   }

                   ov13850->power_on = true;
   +               /* export gpio */
   +               if (!IS_ERR(ov13850->reset_gpio))
   +                       gpiod_export(ov13850->reset_gpio, false);
   +               if (!IS_ERR(ov13850->pwdn_gpio))
   +                       gpiod_export(ov13850->pwdn_gpio, false);
           } else {
                   pm_runtime_put(&client->dev);
   +               __ov13850_power_off(ov13850);
                   ov13850->power_on = false;
   +               /* unexport gpio */
   +               if (!IS_ERR(ov13850->reset_gpio))
   +                       gpiod_unexport(ov13850->reset_gpio);
   +               if (!IS_ERR(ov13850->pwdn_gpio))
   +                       gpiod_unexport(ov13850->pwdn_gpio);
           }

根据sensor需求对__ov13850_power_on进行上电配置。

配置 Android

修改hardware/rockchip/camera/etc/camera/camera3_profiles_rk3399pro.xml
来注册摄像头：

   <CameraSettings>
     <Profiles cameraId="0" name="ov13850" moduleId="m00">
           <Supported_hardware>
               <hwType value="SUPPORTED_HW_RKISP1"/>
           </Supported_hardware>

           <Android_metadata> <!-- Android static metadata only -->
               <!-- Color Correction -->
               <colorCorrection.availableAberrationModes value="OFF"/>
               <!-- Control -->
               <control.availableModes value="AUTO"/>
               <control.aeAvailableAntibandingModes value="OFF,50HZ,60Hz,AUTO"/>
               <control.aeAvailableModes value="ON,OFF"/>
               <control.aeLockAvailable value="FALSE"/>
               <!-- <control.aeAvailableTargetFpsRanges value="15,30,30,30,60,60"/> -->
               <control.aeAvailableTargetFpsRanges value="15,30,30,30"/>
               <control.aeCompensationRange value="-6,6"/>
               <control.aeCompensationStep value="1,3"/>
               <control.afAvailableModes value="OFF,AUTO,MACRO,CONTINUOUS_VIDEO,CONTINUOUS_PICTURE,EDOF"/>
               <control.availableEffects value="OFF"/>
               <!-- <control.awbAvailableModes value="AUTO"/> -->
               <control.awbAvailableModes value="AUTO,INCANDESCENT,FLUORESCENT,DAYLIGHT,CLOUDY_DAYLIGHT"/>
               <control.awbLockAvailable value="false"/>
               <control.availableSceneModes value="DISABLED"/>
               <control.availableVideoStabilizationModes value="OFF"/>
               <control.maxRegions value="1,0,1"/>
               <!-- JPEG -->
               <jpeg.maxSize value="19267584"/>  <!-- w*h*1.5 -->
               <!-- /* TODO */ -->
               <!-- The aspect ratio of the largest thumbnail size will be same as the aspect ratio of largest JPEG output size -->
               <!-- buf hw encode may not support such thumbnail size, so if we should change the jpeg output size? -->
               <jpeg.availableThumbnailSizes value="0,0,128,96,160,96,160,120,256,196"/>
               <!-- <jpeg.availableThumbnailSizes value="0,0,160,120,320,180,320,240"/> -->
               <!-- Lens Info-->
               <!-- TODO: availableApertures now is fake for we do not get the real apertures -->
               <lens.info.availableApertures value="2.0"/> <!-- HAL may override this value from CMC for RAW sensors -->
               <lens.info.availableFocalLengths value="2.04"/> <!-- HAL may override this value from CMC for RAW sensors -->
               <lens.info.availableOpticalStabilization value="OFF"/> <!-- OPTIONS: OFF, ON -->
               <lens.info.hyperfocalDistance value="0.0"/> <!-- HAL may override this value from CMC for RAW sensors -->
               <lens.info.minimumFocusDistance value="0.1"/> <!-- HAL may override this value from CMC for RAW sensors -->
               <!-- Lens -->
               <lens.facing value="BACK"/>
               <!-- Request -->
               <request.maxNumOutputStreams value="1,2,1"/>
               <request.pipelineMaxDepth value="4"/>
               <request.maxNumInputStreams value="0"/>
               <request.partialResultCount value="1"/>
               <!-- <request.availableCapabilities value="BACKWARD_COMPATIBLE,YUV_REPROCESSING,PRIVATE_REPROCESSING"/> -->
               <request.availableCapabilities value="BACKWARD_COMPATIBLE"/>
               <request.availableRequestKeys value="blackLevel.lock,
                   colorCorrection.aberrationMode,
                   colorCorrection.gains,
                   colorCorrection.transform,
                   control.aeAntibandingMode,
                   control.aeExposureCompensation,
                   control.aeLock,
                   control.aeMode,
                   control.aeTargetFpsRange,
                   control.aePrecaptureTrigger,
                   control.afMode,
                   control.aeRegions,
                   control.afRegions,
                   control.afTrigger,
                   control.awbLock,
                   control.awbMode,
                   control.captureIntent,
                   control.effectMode,
                   control.mode,
                   control.sceneMode,
                   control.videoStabilizationMode,
                   edge.mode,
                   flash.mode,
                   jpeg.gpsLocation,
                   jpeg.orientation,
                   jpeg.quality,
                   jpeg.thumbnailQuality,
                   jpeg.thumbnailSize,
                   lens.aperture,
                   lens.focalLength,
                   lens.opticalStabilizationMode,
                   noiseReduction.mode,
                   scaler.cropRegion,
                   statistics.faceDetectMode,
                   statistics.hotPixelMapMode,
                   statistics.sceneFlicker,
                   statistics.lensShadingMapMode
                   "/>

               <request.availableResultKeys value="colorCorrection.mode,
                   colorCorrection.transform,
                   colorCorrection.gains,
                   colorCorrection.aberrationCorrectionMode,
                   control.aeAntibandingMode,
                   control.aeExposureCompensation,
                   control.aeLock,
                   control.aeMode,
                   control.aeTargetFpsRange,
                   control.aePrecaptureTrigger,
                   control.afMode,
                   control.afRegions,
                   control.afTrigger,
                   control.awbLock,
                   control.awbMode,
                   control.captureIntent,
                   control.effectMode,
                   control.mode,
                   control.sceneMode,
                   control.videoStabilizationMode,
                   control.aeState,
                   control.afState,
                   control.awbState,
                   sync.frameNumber,
                   edge.mode,
                   flash.mode,
                   jpeg.gpsLocation,
                   jpeg.orientation,
                   jpeg.quality,
                   jpeg.thumbnailQuality,
                   jpeg.thumbnailSize,
                   lens.focalLength,
                   lens.aperture,
                   lens.opticalStabilizationMode,
                   request.pipelineDepth,
                   scaler.cropRegion,
                   sensor.testPatternData,
                   sensor.testPatternMode,
                   sensor.timestamp,
                   sensor.rollingShutterSkew,
                   statistics.faceDetectMode,
                   statistics.hotPixelMapMode,
                   statistics.faces,
                   noiseReduction.mode,
                   statistics.sceneFlicker,
                   statistics.lensShadingMapMode
                   "/>
               <request.availableCharacteristicsKeys value="0"/>
               <!-- Scaler -->
               <scaler.availableMaxDigitalZoom value="4.0"/>
               <scaler.availableInputOutputFormatsMap value="IMPLEMENTATION_DEFINED,2,YCbCr_420_888,BLOB,YCbCr_420_888,2,YCbCr_420_888,BLOB"/>
   			<scaler.availableStreamConfigurations value="
   				BLOB,4096x3136,OUTPUT,
   				BLOB,2112x1568,OUTPUT,
                   BLOB,1920x1080,OUTPUT,
                   BLOB,1280x960,OUTPUT,
                   BLOB,1280x720,OUTPUT,
                   BLOB,640x480,OUTPUT,
                   BLOB,352x288,OUTPUT,
                   BLOB,320x240,OUTPUT,
                   BLOB,176x144,OUTPUT,
                   YCbCr_420_888,2112x1568,OUTPUT,
                   YCbCr_420_888,1920x1080,OUTPUT,
                   YCbCr_420_888,1280x960,OUTPUT,
                   YCbCr_420_888,1280x720,OUTPUT,
                   YCbCr_420_888,640x480,OUTPUT,
                   YCbCr_420_888,352x288,OUTPUT,
                   YCbCr_420_888,320x240,OUTPUT,
                   YCbCr_420_888,176x144,OUTPUT,
                   IMPLEMENTATION_DEFINED,2112x1568,OUTPUT,
                   IMPLEMENTATION_DEFINED,1920x1080,OUTPUT,
                   IMPLEMENTATION_DEFINED,1280x960,OUTPUT,
                   IMPLEMENTATION_DEFINED,1280x720,OUTPUT,
                   IMPLEMENTATION_DEFINED,640x480,OUTPUT,
                   IMPLEMENTATION_DEFINED,352x288,OUTPUT,
                   IMPLEMENTATION_DEFINED,320x240,OUTPUT,
                   IMPLEMENTATION_DEFINED,176x144,OUTPUT"/>
   			<scaler.availableMinFrameDurations value="
   				BLOB,4096x3136,150000000,
   				BLOB,2112x1568,33333333,
                   BLOB,1920x1080,33333333,
                   BLOB,1280x960,33333333,
                   BLOB,1280x720,33333333,
                   BLOB,640x480,33333333,
                   BLOB,352x288,33333333,
                   BLOB,320x240,33333333,
                   BLOB,176x144,33333333,
                   YCbCr_420_888,2112x1568,33333333,
                   YCbCr_420_888,1920x1080,33333333,
                   YCbCr_420_888,1280x960,33333333,
                   YCbCr_420_888,1280x720,33333333,
                   YCbCr_420_888,640x480,33333333,
                   IMPLEMENTATION_DEFINED,2112x1568,33333333,
                   IMPLEMENTATION_DEFINED,1920x1080,33333333,
                   IMPLEMENTATION_DEFINED,1280x960,33333333,
                   IMPLEMENTATION_DEFINED,1280x720,33333333,
                   IMPLEMENTATION_DEFINED,640x480,33333333,
                   IMPLEMENTATION_DEFINED,352x288,33333333,
                   IMPLEMENTATION_DEFINED,320x240,33333333,
                   IMPLEMENTATION_DEFINED,176x144,33333333" />
   			<scaler.availableStallDurations value="
   												   BLOB,4096x3136,150000000,
   												   BLOB,2112x1568,33333333,
                                                      BLOB,1920x1080,33333333,
                                                      BLOB,1280x960,33333333,
                                                      BLOB,1280x720,33333333,
                                                      BLOB,640x480,33333333,
                                                      BLOB,352x288,33333333,
                                                      BLOB,320x240,33333333,
                                                      BLOB,176x144,33333333" />
               <scaler.croppingType value="CENTER_ONLY"/>
               <!-- Sensor Info -->
               <sensor.info.activeArraySize value="0,0,4224,3136"/>
               <sensor.info.sensitivityRange value="32,2400"/>
               <sensor.info.colorFilterArrangement value="BGGR"/> <!-- HAL may override this value from CMC for RAW sensors -->
               <sensor.info.exposureTimeRange value="100000,333333330"/>
               <sensor.info.maxFrameDuration value="66666666"/>
               <sensor.info.physicalSize value="5.5,4.5"/> <!-- 4224x1.12um 3136x1.12um -->
               <sensor.info.pixelArraySize value="4224x3136"/>
               <sensor.info.whiteLevel value="0"/> <!-- HAL may override this value from CMC for RAW sensors -->
               <sensor.info.timestampSource value="UNKNOWN"/>
               <!-- Sensor -->
               <sensor.baseGainFactor value="0,1"/> <!-- HAL may override this value from CMC for RAW sensors -->
               <sensor.blackLevelPattern value="0,0,0,0"/>
               <sensor.maxAnalogSensitivity value="2400"/> <!-- HAL may override this value from CMC for RAW sensors -->
               <sensor.orientation value="180"/>
               <sensor.profileHueSatMapDimensions value="0,0,0"/>
               <sensor.availableTestPatternModes value="OFF,COLOR_BARS"/>
               <!-- Info -->
               <info.supportedHardwareLevel value="LIMITED"/>
               <!-- shading -->
               <!-- <shading.availableModes value="OFF"/> -->
               <!-- Statistics Info -->
               <statistics.info.availableFaceDetectModes value="OFF"/>
               <statistics.info.histogramBucketCount value="0"/>
               <statistics.info.maxFaceCount value="0"/>
               <statistics.info.availableHotPixelMapModes value="OFF"/>
               <statistics.info.availableLensShadingMapModes value="OFF"/>
               <!-- Flash -->
               <flash.colorTemperature value="0"/>
               <flash.maxEnergy value="0"/>
               <!-- Flash info -->
               <flash.info.available value="FALSE"/>
               <flash.info.chargeDuration value="1000000"/>
               <flash.maxEnergy value="10"/>
               <!-- Sync -->
               <sync.maxLatency value="PER_FRAME_CONTROL"/>
               <!-- maxCaptureStall -->
               <reprocess.maxCaptureStall value="4"/>
               <!-- Edge -->
               <edge.availableEdgeModes value="OFF,FAST,HIGH_QUALITY"/>
               <!-- Noise Reduction -->
               <noiseReduction.availableNoiseReductionModes value="OFF,FAST,HIGH_QUALITY"/>

           </Android_metadata>

   <!-- ******************PSL specific section start **************************************************************-->
           <Hal_tuning_RKISP1> <!-- Parameters to tune the HAL and hacks for the HAL that are camera dependent -->
               <flipping value="" value_v=""/> <!-- value: SENSOR_FLIP_H or "", value_v: SENSOR_FLIP_V or "" -->
               <supportIsoMap value="false"/>
               <supportTuningSize value="4224x3136, 2112x1568"/>
           </Hal_tuning_RKISP1>

           <Sensor_info_RKISP1> <!-- Information that parametrizes the behavior or qualities of the physical sensor -->
               <sensorType value="SENSOR_TYPE_RAW"/> <!-- SENSOR_TYPE_SOC or SENSOR_TYPE_RAW -->
               <exposure.sync value="true"/> <!-- compensate expsure sync-->
               <sensor.digitalGain value="false"/> <!-- digital gain support on sensor-->
               <gain.lag value="2"/> <!-- camera3 HAL CPF parameters moved here start-->
               <exposure.lag value="2"/>
               <fov value= "54.8" value_v="42.5"/>
               <statistics.initialSkip value="1"/> <!-- camera3 HAL CPF parameters moved here end-->
               <frame.initialSkip value="3"/> <!-- camera3 HAL CPF parameters moved here end-->
               <isoAnalogGain1 value="75"/> <!--Pseudo ISO corresponding analog gain value 1.0. -->
               <cITMaxMargin value="10"/> <!--coarse integration time max margin -->
           </Sensor_info_RKISP1>

   <!-- ******************PSL specific section end **************************************************************-->

主要修改的内容如下：

Sensor 名称

   cameraId="0"  //cameraId 后置为 0, 前置为 1, 只有一个 camera 时, 为 0

该名字必须与 Sensor 驱动的名字一致,目前提供的 Sensor 驱动格式如下：

   name="ov13850"
   moduleId="m00"

通过如下命令: adb shell cat /sys/class/video4linux/*/name 可以获取所有
v4l2 设备点节的名字,其中形如 m00_b_ov13850 1-0010 为 sensor 节点名称。
该命令规则中, m00 代表 moduleId ,主要为匹配 len,flash 之 用, ‘b’ 代表
camera 方向为后置,如果是前置则为‘f’,‘ov13850’代表 sensor name ,
‘1-0010’ 代表 I2c 地址。

调试方法

(1) RKISP 驱动如果加载成功,会有 video 及 media 设备存在于/dev/目录下。
系统中可能存在 多个/dev/video 设备,通过/sys 可以查询到 RKISP 注册的
video 节点。

   console:/ # grep '' /sys/class/video4linux/video*/name
   /sys/class/video4linux/video0/name:rkisp1_mainpath
   /sys/class/video4linux/video1/name:rkisp1_selfpath
   /sys/class/video4linux/video2/name:rkisp1_dmapath
   /sys/class/video4linux/video3/name:rkisp1-statistics
   /sys/class/video4linux/video4/name:rkisp1-input-params
   /sys/class/video4linux/video5/name:rkisp1_mainpath
   /sys/class/video4linux/video6/name:rkisp1_selfpath
   /sys/class/video4linux/video7/name:rkisp1_dmapath
   /sys/class/video4linux/video8/name:rkisp1-statistics
   /sys/class/video4linux/video9/name:rkisp1-input-params

(2) 判断 camera 驱动是否加载成功 当所有的 camera 都注册完毕,kernel 会
打印出如下的 log。

   localhost ~ # dmesg | grep Async
   [ 0.682982] rkisp1: Async subdev notifier completed

如发现 kernel 没有 Async subdev notifier completed 这行 log,那么请首先
查看 sensor 是否有相关的报错,I2C 通讯是否成功。

(3) 调试上层相关信息

   dumpsys media.camera

终端下可以直接修改/vendor/etc/camera/camera3_profiles.xml调试各参数并
重启生效

FAQs

1.无法打开摄像头，首先确定sensor I2C是否通信。若不通则可检查mclk以及供
电是否正常（Power/PowerDown/Reset/Mclk/I2cBus）分别排查 2.参考驱动列表
ː ov8858.c Gc2145.c Ov7251 tc35874x.c