v4l2的结构体之v4l2_subdev

淡淡的烟草味﹌ 2022-11-10 14:57 319阅读 0赞

# v4l2的结构体之v4l2\_subdev #

## 简介 ##

子设备，负责实现具体的功能。可将其抽象为具体的某一摄像头传感器，如OV7740、OV7251、OV5640等。

## 定义 ##

### struct v4l2\_subdev ###

/**
     * struct v4l2_subdev - describes a V4L2 sub-device
     *
     * @entity: pointer to &struct media_entity
     * @list: List of sub-devices
     * @owner: The owner is the same as the driver's &struct device owner.
     * @owner_v4l2_dev: true if the &sd->owner matches the owner of @v4l2_dev->dev
     *	owner. Initialized by v4l2_device_register_subdev().
     * @flags: subdev flags. Can be:
     *   %V4L2_SUBDEV_FL_IS_I2C - Set this flag if this subdev is a i2c device;
     *   %V4L2_SUBDEV_FL_IS_SPI - Set this flag if this subdev is a spi device;
     *   %V4L2_SUBDEV_FL_HAS_DEVNODE - Set this flag if this subdev needs a
     *   device node;
     *   %V4L2_SUBDEV_FL_HAS_EVENTS -  Set this flag if this subdev generates
     *   events.
     *
     * @v4l2_dev: pointer to struct &v4l2_device
     * @ops: pointer to struct &v4l2_subdev_ops
     * @internal_ops: pointer to struct &v4l2_subdev_internal_ops.
     *	Never call these internal ops from within a driver!
     * @ctrl_handler: The control handler of this subdev. May be NULL.
     * @name: Name of the sub-device. Please notice that the name must be unique.
     * @grp_id: can be used to group similar subdevs. Value is driver-specific
     * @dev_priv: pointer to private data
     * @host_priv: pointer to private data used by the device where the subdev
     *	is attached.
     * @devnode: subdev device node
     * @dev: pointer to the physical device, if any
     * @fwnode: The fwnode_handle of the subdev, usually the same as
     *	    either dev->of_node->fwnode or dev->fwnode (whichever is non-NULL).
     * @async_list: Links this subdev to a global subdev_list or @notifier->done
     *	list.
     * @asd: Pointer to respective &struct v4l2_async_subdev.
     * @notifier: Pointer to the managing notifier.
     * @subdev_notifier: A sub-device notifier implicitly registered for the sub-
     *		     device using v4l2_device_register_sensor_subdev().
     * @pdata: common part of subdevice platform data
     *
     * Each instance of a subdev driver should create this struct, either
     * stand-alone or embedded in a larger struct.
     *
     * This structure should be initialized by v4l2_subdev_init() or one of
     * its variants: v4l2_spi_subdev_init(), v4l2_i2c_subdev_init().
     */
    struct v4l2_subdev {
    #if defined(CONFIG_MEDIA_CONTROLLER)
    	struct media_entity entity;
    #endif
    	struct list_head list;
    	struct module *owner;
    	bool owner_v4l2_dev;
    	u32 flags;
     
       指向父设备
    	struct v4l2_device *v4l2_dev;
     
       //提供一些控制v4l2设备的接口
    	const struct v4l2_subdev_ops *ops;
     
       //向V4L2框架提供的接口函数
    	const struct v4l2_subdev_internal_ops *internal_ops;
     
       //subdev控制接口
    	struct v4l2_ctrl_handler *ctrl_handler;
     
       //name must be unique
    	char name[V4L2_SUBDEV_NAME_SIZE];
     
    	u32 grp_id;
    	void *dev_priv;
    	void *host_priv;
    	struct video_device *devnode;
    	struct device *dev;
    	struct fwnode_handle *fwnode;
    	struct list_head async_list;
    	struct v4l2_async_subdev *asd;
    	struct v4l2_async_notifier *notifier;
    	struct v4l2_async_notifier *subdev_notifier;
    	struct v4l2_subdev_platform_data *pdata;
    };

### struct v4l2\_subdev\_ops ###

/**
     * struct v4l2_subdev_ops - Subdev operations
     *
     * @core: pointer to &struct v4l2_subdev_core_ops. Can be %NULL
     * @tuner: pointer to &struct v4l2_subdev_tuner_ops. Can be %NULL
     * @audio: pointer to &struct v4l2_subdev_audio_ops. Can be %NULL
     * @video: pointer to &struct v4l2_subdev_video_ops. Can be %NULL
     * @vbi: pointer to &struct v4l2_subdev_vbi_ops. Can be %NULL
     * @ir: pointer to &struct v4l2_subdev_ir_ops. Can be %NULL
     * @sensor: pointer to &struct v4l2_subdev_sensor_ops. Can be %NULL
     * @pad: pointer to &struct v4l2_subdev_pad_ops. Can be %NULL
     */
    struct v4l2_subdev_ops {
        //视频设备通用的操作：初始化、加载FW、上电和RESET等
    	const struct v4l2_subdev_core_ops	*core;
     
    	const struct v4l2_subdev_tuner_ops	*tuner;/* 调谐器操作合集 */
    	const struct v4l2_subdev_audio_ops	*audio;/* 音频操作合集 */
     
       //视频设备的特有操作：设置帧率、裁剪图像、开关视频流等
    	const struct v4l2_subdev_video_ops	*video;/* 视频操作合集 */
    	const struct v4l2_subdev_vbi_ops	*vbi;
    	const struct v4l2_subdev_ir_ops		*ir;
    	const struct v4l2_subdev_sensor_ops	*sensor;
    	const struct v4l2_subdev_pad_ops	*pad;
    };

### struct v4l2\_subdev\_core\_ops ###

struct v4l2_subdev_core_ops {
    	int (*log_status)(struct v4l2_subdev *sd); /* 状态消息 */
    	int (*s_io_pin_config)(struct v4l2_subdev *sd, size_t n,
           struct v4l2_subdev_io_pin_config *pincfg);
    	int (*init)(struct v4l2_subdev *sd, u32 val); /* 初始化设备 */
    	int (*load_fw)(struct v4l2_subdev *sd);       /* 加载firmware */
    	int (*reset)(struct v4l2_subdev *sd, u32 val);/* 重置设备 */
    	int (*s_gpio)(struct v4l2_subdev *sd, u32 val);/* 设置gpio */
    	long (*ioctl)(struct v4l2_subdev *sd, unsigned int cmd, void *arg);/* 处理特殊命令 */
    #ifdef CONFIG_COMPAT
    	long (*compat_ioctl32)(struct v4l2_subdev *sd, unsigned int cmd,
    			       unsigned long arg);
    #endif
    #ifdef CONFIG_VIDEO_ADV_DEBUG
    	int (*g_register)(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg);/* 获取寄存器值 */
    	int (*s_register)(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg);/* 设置寄存器值 */
    #endif
    	int (*s_power)(struct v4l2_subdev *sd, int on); /* 控制设备上下电 */
    	int (*interrupt_service_routine)(struct v4l2_subdev *sd,
            u32 status, bool *handled); /* 中断服务函数 */
    	int (*subscribe_event)(struct v4l2_subdev *sd, struct v4l2_fh *fh,
    			       struct v4l2_event_subscription *sub);
    	int (*unsubscribe_event)(struct v4l2_subdev *sd, struct v4l2_fh *fh,
    				 struct v4l2_event_subscription *sub);
    };

### struct v4l2\_subdev\_tuner\_ops ###

struct v4l2_subdev_tuner_ops {
    	int (*standby)(struct v4l2_subdev *sd);/* 控制standby模式 */
    	int (*s_radio)(struct v4l2_subdev *sd);/* 设置无线设备信息 */
    	int (*s_frequency)(struct v4l2_subdev *sd, const struct v4l2_frequency *freq);/* 设置频率 */
    	int (*g_frequency)(struct v4l2_subdev *sd, struct v4l2_frequency *freq); /* 获取频率 */
    	int (*enum_freq_bands)(struct v4l2_subdev *sd, struct v4l2_frequency_band *band);
    	int (*g_tuner)(struct v4l2_subdev *sd, struct v4l2_tuner *vt); /* 获取调谐器信息 */
    	int (*s_tuner)(struct v4l2_subdev *sd, const struct v4l2_tuner *vt); /* 设置调谐器信息 */
    	int (*g_modulator)(struct v4l2_subdev *sd, struct v4l2_modulator *vm); /* 获取调幅器信息 */
    	int (*s_modulator)(struct v4l2_subdev *sd, const struct v4l2_modulator *vm); /* 设置调幅器信息 */
    	int (*s_type_addr)(struct v4l2_subdev *sd, struct tuner_setup *type); /* 安装调谐器 */
    	int (*s_config)(struct v4l2_subdev *sd, const struct v4l2_priv_tun_config *config); /* 设置配置信息 */
    };

### struct v4l2\_subdev\_audio\_ops ###

struct v4l2_subdev_audio_ops {
    	int (*s_clock_freq)(struct v4l2_subdev *sd, u32 freq); /* 设置音频设备频率 */
    	int (*s_i2s_clock_freq)(struct v4l2_subdev *sd, u32 freq); /* 设置i2s总线频率 */
    	int (*s_routing)(struct v4l2_subdev *sd, u32 input, u32 output, u32 config); /* 设置音频路由 */
    	int (*s_stream)(struct v4l2_subdev *sd, int enable); /* 控制音频流 */
    };

### struct v4l2\_subdev\_pad\_ops ###

/**
     * struct v4l2_subdev_pad_ops - v4l2-subdev pad level operations
     *
     * @init_cfg: initialize the pad config to default values
     * @enum_mbus_code: callback for VIDIOC_SUBDEV_ENUM_MBUS_CODE() ioctl handler
     *		    code.
     * @enum_frame_size: callback for VIDIOC_SUBDEV_ENUM_FRAME_SIZE() ioctl handler
     *		     code.
     *
     * @enum_frame_interval: callback for VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL() ioctl
     *			 handler code.
     *
     * @get_fmt: callback for VIDIOC_SUBDEV_G_FMT() ioctl handler code.
     *
     * @set_fmt: callback for VIDIOC_SUBDEV_S_FMT() ioctl handler code.
     *
     * @get_selection: callback for VIDIOC_SUBDEV_G_SELECTION() ioctl handler code.
     *
     * @set_selection: callback for VIDIOC_SUBDEV_S_SELECTION() ioctl handler code.
     *
     * @get_edid: callback for VIDIOC_SUBDEV_G_EDID() ioctl handler code.
     *
     * @set_edid: callback for VIDIOC_SUBDEV_S_EDID() ioctl handler code.
     *
     * @dv_timings_cap: callback for VIDIOC_SUBDEV_DV_TIMINGS_CAP() ioctl handler
     *		    code.
     *
     * @enum_dv_timings: callback for VIDIOC_SUBDEV_ENUM_DV_TIMINGS() ioctl handler
     *		     code.
     *
     * @link_validate: used by the media controller code to check if the links
     *		   that belongs to a pipeline can be used for stream.
     *
     * @get_frame_desc: get the current low level media bus frame parameters.
     *
     * @set_frame_desc: set the low level media bus frame parameters, @fd array
     *                  may be adjusted by the subdev driver to device capabilities.
     */
    struct v4l2_subdev_pad_ops {
    	int (*init_cfg)(struct v4l2_subdev *sd,
    			struct v4l2_subdev_pad_config *cfg);
    	int (*enum_mbus_code)(struct v4l2_subdev *sd,
    			      struct v4l2_subdev_pad_config *cfg,
    			      struct v4l2_subdev_mbus_code_enum *code);
    	int (*enum_frame_size)(struct v4l2_subdev *sd,
    			       struct v4l2_subdev_pad_config *cfg,
    			       struct v4l2_subdev_frame_size_enum *fse);
    	int (*enum_frame_interval)(struct v4l2_subdev *sd,
    				   struct v4l2_subdev_pad_config *cfg,
    				   struct v4l2_subdev_frame_interval_enum *fie);
    	int (*get_fmt)(struct v4l2_subdev *sd,
    		       struct v4l2_subdev_pad_config *cfg,
    		       struct v4l2_subdev_format *format);
    	int (*set_fmt)(struct v4l2_subdev *sd,
    		       struct v4l2_subdev_pad_config *cfg,
    		       struct v4l2_subdev_format *format);
    	int (*get_selection)(struct v4l2_subdev *sd,
    			     struct v4l2_subdev_pad_config *cfg,
    			     struct v4l2_subdev_selection *sel);
    	int (*set_selection)(struct v4l2_subdev *sd,
    			     struct v4l2_subdev_pad_config *cfg,
    			     struct v4l2_subdev_selection *sel);
    	int (*get_edid)(struct v4l2_subdev *sd, struct v4l2_edid *edid);
    	int (*set_edid)(struct v4l2_subdev *sd, struct v4l2_edid *edid);
    	int (*dv_timings_cap)(struct v4l2_subdev *sd,
    			      struct v4l2_dv_timings_cap *cap);
    	int (*enum_dv_timings)(struct v4l2_subdev *sd,
    			       struct v4l2_enum_dv_timings *timings);
    #ifdef CONFIG_MEDIA_CONTROLLER
    	int (*link_validate)(struct v4l2_subdev *sd, struct media_link *link,
    			     struct v4l2_subdev_format *source_fmt,
    			     struct v4l2_subdev_format *sink_fmt);
    #endif /* CONFIG_MEDIA_CONTROLLER */
    	int (*get_frame_desc)(struct v4l2_subdev *sd, unsigned int pad,
    			      struct v4l2_mbus_frame_desc *fd);
    	int (*set_frame_desc)(struct v4l2_subdev *sd, unsigned int pad,
    			      struct v4l2_mbus_frame_desc *fd);
    };