devbox
Gausst松鼠会
这个屌丝很懒，什么也没留下！
关注作者
热门标签
热门文章
当前位置:   article > 正文

Android 相机启动流程笔记

作者：Gausst松鼠会 | 2024-02-25 05:19:31

赞

踩

Android 相机启动流程笔记

90300989cb7a97628191282627f2690b.gif

和你一起终身学习，这里是程序员Android

经典好文推荐，通过阅读本文，您将收获以下知识点:

一、Camera 框架介绍：

Camera的框架分为Kernel部分和hal部分，其中kernel部分主要有两块：

  • image sensor driver，负责具体型号的sensor的id检测，上电，以及在preview、capture、初始化、3A等等功能设定时的寄存器配置；

  • isp driver，通过DMA将sensor数据流上传；

HAL层部分主要有三部分组成：

  • imageio，主要负责数据buffer上传的pipe；

  • drv，包含imgsensor和isp的hal层控制；

  • feature io，包含各种3A等性能配置；

这篇内容主要介绍开机过程中search sensor以及上电流程等内容。

二、Camera 启动流程

1、CameraService是在开机时启动的，启动后进行searchSensor的操作，会search系统有多少camera，开机时的search操作，只进行camera支持数量的遍历，以及sensor ID的读取操作，如下是hal部分的ASTAH绘制调用流程图，对应的接口的文件路径：

  • HalSensorList：
    vendor/mediatek/proprietary/hardware/mtkcam/drv/src/sensor/common/v1/HalSensorList.enumList.cpp
    vendor/mediatek/proprietary/hardware/mtkcam/drv/src/sensor/common/v1/HalSensorList.cpp

  • SeninfDrv：
    vendor/mediatek/proprietary/hardware/mtkcam/drv/src/sensor/mt6765/seninf_drv.cpp

  • SensorDrv：
    vendor/mediatek/proprietary/hardware/mtkcam/drv/src/sensor/common/v1/imgsensor_drv.cpp

08bb682884c86c6c3fb7725e88d01f78.png

(1) 这里先看enumerateSensor_Locked完成的工作，直接看代码：

  1. MUINT HalSensorList::searchSensors()
  2. {
  3.     Mutex::Autolock _l(mEnumSensorMutex);
  4.     MY_LOGD("searchSensors");
  5.     return  enumerateSensor_Locked();
  6. }
  7.  
  8. MUINT HalSensorList::enumerateSensor_Locked()
  9. {
  10.     SensorDrv *const pSensorDrv = SensorDrv::get();
  11.     SeninfDrv *const pSeninfDrv = SeninfDrv::createInstance();
  12.     //初始化seninf,配置ISP相关内容
  13.     pSeninfDrv->init();
  14.  
  15.     //将所有的clk全部打开
  16.     pSeninfDrv->setAllMclkOnOff(ISP_DRIVING_8MA, TRUE);
  17.  
  18.     pSensorDrv->init();
  19.     for (MUINT i = IMGSENSOR_SENSOR_IDX_MIN_NUM; i <= max_index_of_camera; i++) {
  20.         if((ret = pSensorDrv->searchSensor((IMGSENSOR_SENSOR_IDX)i)) == SENSOR_NO_ERROR){
  21.             //query sensorinfo
  22.            querySensorDrvInfo((IMGSENSOR_SENSOR_IDX)i);
  23.            //fill in metadata
  24.            buildSensorMetadata((IMGSENSOR_SENSOR_IDX)i);
  25.            pSensorInfo = pSensorDrv->getSensorInfo((IMGSENSOR_SENSOR_IDX)i);
  26.            addAndInitSensorEnumInfo_Locked(
  27.                 (IMGSENSOR_SENSOR_IDX)i,
  28.                 mapToSensorType(pSensorInfo->GetType()),
  29.                 pSensorInfo->getDrvMacroName());
  30.         }
  31.     }     
  32. }

(２) 下面主要看下searchSensor的流程，这里有去获取sensorList的内容：

  1. MINT32 ImgSensorDrv::searchSensor(IMGSENSOR_SENSOR_IDX sensorIdx)
  2. {
  3.     GetSensorInitFuncList(&pSensorInitFunc);
  4.  
  5.     featureControl(sensorIdx, SENSOR_FEATURE_SET_DRIVER, (MUINT8 *)&idx, &featureParaLen);
  6.  
  7.     NSFeature::SensorInfoBase* pSensorInfo = pSensorInitFunc[idx].pSensorInfo;
  8. }

GetSensorInitFuncList是获取到配置的sensorList的内容，此sensorList需要与kernel层配置的一致，不一致的话在打开camera时会出现异常：
文件位置：
vendor/mediatek/proprietary/custom/mt6765/hal/imgsensor_src/sensorlist.cpp

  1. MSDK_SENSOR_INIT_FUNCTION_STRUCT SensorList[] =
  2. {
  3. #if defined(IMX486_MIPI_RAW)
  4.     RAW_INFO(IMX486_SENSOR_ID, SENSOR_DRVNAME_IMX486_MIPI_RAW, CAM_CALGetCalData),
  5. #endif
  6. //.....
  7. }
  8.  
  9. UINT32 GetSensorInitFuncList(MSDK_SENSOR_INIT_FUNCTION_STRUCT **ppSensorList)
  10. {
  11.     if (NULL == ppSensorList) {
  12.         ALOGE("ERROR: NULL pSensorList\n");
  13.         return MHAL_UNKNOWN_ERROR;
  14.     }
  15.     *ppSensorList = &SensorList[0];
  16.     return MHAL_NO_ERROR;
  17. }

对应的MSDK_SENSOR_INIT_FUNCTION_STRUCT的结构体如下：

  1. typedef struct
  2. {
  3.     MUINT32 sensorType;
  4.     MUINT32 SensorId;
  5.     MUINT8  drvname[32];
  6.     NSFeature::SensorInfoBase* pSensorInfo;
  7.     MUINT32 (*getCameraIndexMgr)(CAMERA_DATA_TYPE_ENUM CameraDataType, MVOID *pDataBuf, MUINT32 size);
  8.     MUINT32 (*getCameraCalData)(UINT32* pGetSensorCalData);
  9. } MSDK_SENSOR_INIT_FUNCTION_STRUCT, *PMSDK_SENSOR_INIT_FUNCTION_STRUCT;

(3) featureControl的setDriver流程：
文件位置：
vendor/mediatek/proprietary/hardware/mtkcam/drv/src/sensor/common/v1/imgsensor_drv.cpp

  1. MINT32  ImgSensorDrv::featureControl(
  2.     IMGSENSOR_SENSOR_IDX sensorIdx,
  3.     ACDK_SENSOR_FEATURE_ENUM FeatureId,
  4.     MUINT8 *pFeaturePara,
  5.     MUINT32 *pFeatureParaLen
  6. )
  7. {
  8.     //结构ACDK_SENSOR_FEATURECONTROL_STRUCT和kernel中一致
  9.     featureCtrl.InvokeCamera = sensorIdx;
  10.     featureCtrl.FeatureId = FeatureId;//SENSOR_FEATURE_SET_DRIVER
  11.     featureCtrl.pFeaturePara = pFeaturePara;
  12.     featureCtrl.pFeatureParaLen = pFeatureParaLen;
  13.  
  14.     if (ioctl(m_fdSensor, KDIMGSENSORIOC_X_FEATURECONCTROL , &featureCtrl) < 0) {
  15.         LOG_ERR("[featureControl] Err-ctrlCode (%s)", strerror(errno));
  16.         return -errno;
  17.     }
  18.  
  19.     return SENSOR_NO_ERROR;
  20. }

三、kernel 启动流程

先来看整体的框架图如下：

66ee089ccc96a81d935ae69e4cb1fe8b.png

1、set clock 设置时钟

  1. static long imgsensor_ioctl(
  2.     struct file *a_pstFile,
  3.     unsigned int a_u4Command,
  4.     unsigned long a_u4Param)
  5. {
  6.     case KDIMGSENSORIOC_X_SET_MCLK_PLL:
  7.         i4RetValue = imgsensor_clk_set(
  8.             &pgimgsensor->clk,
  9.             (struct ACDK_SENSOR_MCLK_STRUCT *)pBuff);
  10.         break;
  11.         //......
  12. }
  13.  
  14. int imgsensor_clk_set(
  15.     struct IMGSENSOR_CLK *pclk, struct ACDK_SENSOR_MCLK_STRUCT *pmclk)
  16. {
  17.     if (pmclk->on) {
  18.         clk_prepare_enable(pclk->imgsensor_ccf[mclk_index])
  19.         ret = clk_set_parent(
  20.             pclk->imgsensor_ccf[pmclk->TG],
  21.             pclk->imgsensor_ccf[mclk_index]);
  22.     } else {
  23.         clk_disable_unprepare(pclk->imgsensor_ccf[mclk_index]);
  24.     }
  25. }

2、set driver

  1. static long imgsensor_ioctl(
  2.     struct file *a_pstFile,
  3.     unsigned int a_u4Command,
  4.     unsigned long a_u4Param) 
  5. {
  6.     case KDIMGSENSORIOC_X_FEATURECONCTROL:
  7.         i4RetValue = adopt_CAMERA_HW_FeatureControl(pBuff);
  8.         break;
  9.         //......
  10. }
  11.  
  12. static inline int adopt_CAMERA_HW_FeatureControl(void *pBuf)
  13. {
  14.     /* copy from user */
  15.     switch (pFeatureCtrl->FeatureId) {
  16.         case SENSOR_FEATURE_SET_DRIVER:
  17.         {
  18.             MINT32 drv_idx;
  19.  
  20.             psensor->inst.sensor_idx = pFeatureCtrl->InvokeCamera;
  21.             drv_idx = imgsensor_set_driver(psensor);
  22.  
  23.             memcpy(pFeaturePara, &drv_idx, FeatureParaLen);
  24.             break;
  25.         }
  26.     }
  27. }

遍历CONFIG_CUSTOM_KERNEL_IMGSENSOR的内容，然后看sensorList是否对应，并获取对应的下标，调用imgsensor_check_is_alive进行上下电并读取ID 的操作：

  1. struct IMGSENSOR_INIT_FUNC_LIST kdSensorList[MAX_NUM_OF_SUPPORT_SENSOR] = {
  2. #if defined(XXXXXX_MIPI_RAW)
  3.         {XXXXXX_SENSOR_ID,
  4.         SENSOR_DRVNAME_XXXXXX_MIPI_RAW,
  5.         XXXXXX_MIPI_RAW_SensorInit},
  6. #endif
  7.     //......
  8. }
  9.  
  10. int imgsensor_set_driver(struct IMGSENSOR_SENSOR *psensor)
  11. {
  12.     struct IMGSENSOR_SENSOR_INST    *psensor_inst = &psensor->inst;
  13.     struct IMGSENSOR_INIT_FUNC_LIST *pSensorList  = kdSensorList;
  14.     //获取config的size
  15.     char *sensor_configs = STRINGIZE(CONFIG_CUSTOM_KERNEL_IMGSENSOR);
  16.     imgsensor_i2c_init(&psensor_inst->i2c_cfg,
  17.     imgsensor_custom_config[psensor->inst.sensor_idx].i2c_dev);
  18.  
  19.     memcpy(psensor_list_config, sensor_configs+1, strlen(sensor_configs)-2);
  20.     //对应config字符串进行按空格进行拆解
  21.     driver_name = strsep(&psensor_list_config, " \0");
  22.  
  23.     while (driver_name != NULL) {
  24.         for (j = 0; j < MAX_NUM_OF_SUPPORT_SENSOR; j++) {
  25.             //判断对应的init函数是否存在
  26.             if (pSensorList[j].init == NULL)
  27.                 break;
  28.             else if (!strcmp(driver_name, pSensorList[j].name)) {
  29.                 //如果在config中和sensorlist中同时有定义进行赋值
  30.                 orderedSearchList[i++] = j;
  31.                 break;
  32.             }
  33.         }
  34.         driver_name = strsep(&psensor_list_config, " \0");
  35.     }
  36.  
  37.     for (i = 0; i < MAX_NUM_OF_SUPPORT_SENSOR; i++) {
  38.         //上面获取到的sensorlist的下标
  39.         drv_idx = orderedSearchList[i];
  40.         if (pSensorList[drv_idx].init) {
  41.             //调用对应驱动的init函数
  42.             pSensorList[drv_idx].init(&psensor->pfunc);
  43.             if (psensor->pfunc) {
  44.                 psensor_inst->psensor_name =
  45.                     (char *)pSensorList[drv_idx].name;
  46.                     //到这里是重点，进行上电读取ID的操作
  47.                 if (!imgsensor_check_is_alive(psensor)) {
  48.                     ret = drv_idx;
  49.                 }
  50.             }
  51.         }
  52.     }
  53. }

下面看对应的上下电以及读取ID的操作：

  1. static inline int imgsensor_check_is_alive(struct IMGSENSOR_SENSOR *psensor)
  2. {
  3.     struct IMGSENSOR_SENSOR_INST  *psensor_inst = &psensor->inst;
  4.     //上电
  5.     err = imgsensor_hw_power(&pgimgsensor->hw,
  6.                 psensor,
  7.                 psensor_inst->psensor_name,
  8.                 IMGSENSOR_HW_POWER_STATUS_ON);
  9.     //读取ID
  10.     imgsensor_sensor_feature_control(
  11.             psensor,
  12.             SENSOR_FEATURE_CHECK_SENSOR_ID,
  13.             (MUINT8 *)&sensorID,
  14.             &retLen);
  15.  
  16.     if (sensorID == 0 || sensorID == 0xFFFFFFFF) {
  17.         pr_info("Fail to get sensor ID %x\n", sensorID);
  18.         err = ERROR_SENSOR_CONNECT_FAIL;
  19.     } else {
  20.         pr_info(" Sensor found ID = 0x%x\n", sensorID);
  21.         err = ERROR_NONE;
  22.     }
  23.     //下电
  24.     imgsensor_hw_power(&pgimgsensor->hw,
  25.         psensor,
  26.         psensor_inst->psensor_name,
  27.         IMGSENSOR_HW_POWER_STATUS_OFF);
  28.  
  29.     return err ? -EIO:err;
  30. }

3、上电相关

上电时序配置：

  1. struct IMGSENSOR_HW_POWER_INFO {
  2.     enum IMGSENSOR_HW_PIN       pin;
  3.     enum IMGSENSOR_HW_PIN_STATE pin_state_on;
  4.     u32  pin_on_delay;
  5.     enum IMGSENSOR_HW_PIN_STATE pin_state_off;
  6.     u32  pin_off_delay;
  7. };
  8.  
  9. struct IMGSENSOR_HW_POWER_SEQ sensor_power_sequence[] = {
  10.     //……
  11.     #if defined(XXXXXX_MIPI_RAW)
  12.         {
  13.             SENSOR_DRVNAME_XXXXXX_MIPI_RAW,
  14.             {
  15.                 {RST, Vol_Low, 0},
  16.                 {DVDD, Vol_1100, 1},
  17.                 {AVDD, Vol_2800, 1},
  18.                 {DOVDD, Vol_1800, 1},
  19.                 {RST, Vol_High, 1},
  20.                 {SensorMCLK, Vol_High, 0},
  21.             },
  22.         },
  23.     #endif
  24. }

对应的控制的流程如下：

  1. static enum IMGSENSOR_RETURN imgsensor_hw_power_sequence(
  2.     struct IMGSENSOR_HW             *phw,
  3.     enum   IMGSENSOR_SENSOR_IDX      sensor_idx,
  4.     enum   IMGSENSOR_HW_POWER_STATUS pwr_status,
  5.     struct IMGSENSOR_HW_POWER_SEQ   *ppower_sequence,
  6.     char *pcurr_idx)
  7. {
  8.     ppwr_info = ppwr_seq->pwr_info;
  9.     // 上电
  10.     while (ppwr_info->pin != IMGSENSOR_HW_PIN_NONE &&
  11.         ppwr_info < ppwr_seq->pwr_info + IMGSENSOR_HW_POWER_INFO_MAX) {
  12.  
  13.         if (pwr_status == IMGSENSOR_HW_POWER_STATUS_ON &&
  14.            ppwr_info->pin != IMGSENSOR_HW_PIN_UNDEF) {
  15.             pdev = phw->pdev[psensor_pwr->id[ppwr_info->pin]];
  16.             if (pdev->set != NULL)
  17.                 //调用GPIO或者regulator的set 电压操作，这里的pdev在imgsensor_probe中已经设置
  18.                 pdev->set( 
  19.                     pdev->pinstance,
  20.                     sensor_idx,
  21.                     ppwr_info->pin,
  22.                     ppwr_info->pin_state_on);
  23.  
  24.             mdelay(ppwr_info->pin_on_delay);
  25.         }
  26.         // 从上到下依次上电
  27.         ppwr_info++;
  28.         pin_cnt++;
  29.     }
  30.  
  31.     // 下电操作
  32.     if (pwr_status == IMGSENSOR_HW_POWER_STATUS_OFF) {
  33.         while (pin_cnt) {
  34.             //从下到上依次下电
  35.             ppwr_info--;
  36.             pin_cnt--;
  37.  
  38.             if (ppwr_info->pin != IMGSENSOR_HW_PIN_UNDEF) {
  39.                 pdev =
  40.                     phw->pdev[psensor_pwr->id[ppwr_info->pin]];
  41.                 mdelay(ppwr_info->pin_on_delay);
  42.  
  43.                 if (pdev->set != NULL)
  44.                     pdev->set(
  45.                         pdev->pinstance,
  46.                         sensor_idx,
  47.                         ppwr_info->pin,
  48.                         ppwr_info->pin_state_off);
  49.             }
  50.         }
  51.     }
  52.  
  53.     /* wait for power stable */
  54.     if (pwr_status == IMGSENSOR_HW_POWER_STATUS_ON)
  55.         mdelay(5);
  56.     return IMGSENSOR_RETURN_SUCCESS;
  57. }

四、总结

通过上面的代码流程，可以知道上开机时，camera模块先会将所有的MCLK打开，然后对依次对对应的sensor进行上电，读取ID(判断I2C是否正常通讯)。这部分调试过程中遇到的问题总结如下：

1、ID读取不到，I2C不通

  • 检查上电时序，３项电压（AVDD/DVDD/IOVDD）是否正确；

  • I2C地址及通道设置是否正确；

  • 检查cfg_setting_imgsensor.cpp中MCLK和HW链接配置是否正确；

2、Camera 启动时间过长

  • 检查Sensor上电时序要求的延时，是否有偏长的情况；

  • 去掉多余的I2C地址，因为大部分驱动会多添加一些地址；

  • OTP的加载调整到每次开机时第一次打开加载，之后不加载；

  • sensorInit如果时间过长，可以调节I2C speed(400->1000)；

3、preview 阶段耗时

  • 检查streamOn/Off的耗时；

  • preview_init是否有较长时间的耗时

  • 以及延时操作使用mdelay代替msleep；

  • pre_delay_frame/cap_delay_frame丢帧操作是否合适；

4、低电流、功耗相关问题

  • 检查电压是否都有下电成功，防止漏电；

  • 对于共pin的sensor，在操作时是否有做好workaround；

  • 将I2C寄存器单个读写，调整为连续读写的方式也有一定优化；

  • sensor的PIN是否有被其他模块占用，异常操作的行为；

友情推荐：

Android 开发干货集锦

至此，本篇已结束。转载网络的文章，小编觉得很优秀，欢迎点击阅读原文，支持原创作者，如有侵权，恳请联系小编删除，欢迎您的建议与指正。同时期待您的关注，感谢您的阅读，谢谢！

03b38985121e177bac9804493fb63001.jpeg

点个在看，方便您使用时快速查找！

声明：本文内容由网友自发贡献，不代表【wpsshop博客】立场，版权归原作者所有，本站不承担相应法律责任。如您发现有侵权的内容，请联系我们。转载请注明出处：https://www.wpsshop.cn/w/Gausst松鼠会/article/detail/138938
推荐阅读
相关标签

Copyright © 2003-2013 www.wpsshop.cn 版权所有，并保留所有权利。

  

闽ICP备14008679号