/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * VIDEO MOTION CODECs internal API for video devices * * Interface for MJPEG (and maybe later MPEG/WAVELETS) codec's * bound to a master device. * * (c) 2002 Wolfgang Scherr <[email protected]> */ /* =================== */ /* general description */ /* =================== */ /* * Should ease the (re-)usage of drivers supporting cards with (different) * video codecs. The codecs register to this module their functionality, * and the processors (masters) can attach to them if they fit. * * The codecs are typically have a "strong" binding to their master - so I * don't think it makes sense to have a full blown interfacing as with e.g. * i2c. If you have an other opinion, let's discuss & implement it :-))) * * Usage: * * The slave has just to setup the videocodec structure and use two functions: * videocodec_register(codecdata); * videocodec_unregister(codecdata); * The best is just calling them at module (de-)initialisation. * * The master sets up the structure videocodec_master and calls: * codecdata=videocodec_attach(master_codecdata); * videocodec_detach(codecdata); * * The slave is called during attach/detach via functions setup previously * during register. At that time, the master_data pointer is set up * and the slave can access any io registers of the master device (in the case * the slave is bound to it). Otherwise it doesn't need this functions and * therefor they may not be initialized. * * The other functions are just for convenience, as they are for sure used by * most/all of the codecs. The last ones may be omitted, too. * * See the structure declaration below for more information and which data has * to be set up for the master and the slave. * * ---------------------------------------------------------------------------- * The master should have "knowledge" of the slave and vice versa. So the data * structures sent to/from slave via set_data/get_data set_image/get_image are * device dependent and vary between MJPEG/MPEG/WAVELET/... devices. (!!!!) * ---------------------------------------------------------------------------- */ /* ========================================== */ /* description of the videocodec_io structure */ /* ========================================== */ /* * ==== master setup ==== * name -> name of the device structure for reference and debugging * master_data -> data ref. for the master (e.g. the zr36055,57,67) * readreg -> ref. to read-fn from register (setup by master, used by slave) * writereg -> ref. to write-fn to register (setup by master, used by slave) * this two functions do the lowlevel I/O job * * ==== slave functionality setup ==== * slave_data -> data ref. for the slave (e.g. the zr36050,60) * check -> fn-ref. checks availability of an device, returns -EIO on failure or * the type on success * this makes espcecially sense if a driver module supports more than * one codec which may be quite similar to access, nevertheless it * is good for a first functionality check * * -- main functions you always need for compression/decompression -- * * set_mode -> this fn-ref. resets the entire codec, and sets up the mode * with the last defined norm/size (or device default if not * available) - it returns 0 if the mode is possible * set_size -> this fn-ref. sets the norm and image size for * compression/decompression (returns 0 on success) * the norm param is defined in videodev2.h (V4L2_STD_*) * * additional setup may be available, too - but the codec should work with * some default values even without this * * set_data -> sets device-specific data (tables, quality etc.) * get_data -> query device-specific data (tables, quality etc.) * * if the device delivers interrupts, they may be setup/handled here * setup_interrupt -> codec irq setup (not needed for 36050/60) * handle_interrupt -> codec irq handling (not needed for 36050/60) * if the device delivers pictures, they may be handled here * put_image -> puts image data to the codec (not needed for 36050/60) * get_image -> gets image data from the codec (not needed for 36050/60) * the calls include frame numbers and flags (even/odd/...) * if needed and a flag which allows blocking until its ready */ /* ============== */ /* user interface */ /* ============== */ /* * Currently there is only a information display planned, as the layer * is not visible for the user space at all. * * Information is available via procfs. The current entry is "/proc/videocodecs" * but it makes sense to "hide" it in the /proc/video tree of v4l(2) --TODO--. * * A example for such an output is: * * <S>lave or attached <M>aster name type flags magic (connected as) * S zr36050 0002 0000d001 00000000 (TEMPLATE) * M zr36055[0] 0001 0000c001 00000000 (zr36050[0]) * M zr36055[1] 0001 0000c001 00000000 (zr36050[1]) */ /* =============================================== */ /* special defines for the videocodec_io structure */ /* =============================================== */ #ifndef __LINUX_VIDEOCODEC_H #define __LINUX_VIDEOCODEC_H #include <linux/debugfs.h> #include <linux/videodev2.h> #define CODEC_DO_COMPRESSION … #define CODEC_DO_EXPANSION … /* this are the current codec flags I think they are needed */ /* -> type value in structure */ #define CODEC_FLAG_JPEG … #define CODEC_FLAG_MPEG … #define CODEC_FLAG_DIVX … #define CODEC_FLAG_WAVELET … // room for other types #define CODEC_FLAG_MAGIC … #define CODEC_FLAG_HARDWARE … #define CODEC_FLAG_VFE … #define CODEC_FLAG_ENCODER … #define CODEC_FLAG_DECODER … #define CODEC_FLAG_NEEDIRQ … #define CODEC_FLAG_RDWRPIC … /* a list of modes, some are just examples (is there any HW?) */ #define CODEC_MODE_BJPG … #define CODEC_MODE_LJPG … #define CODEC_MODE_MPEG1 … #define CODEC_MODE_MPEG2 … #define CODEC_MODE_MPEG4 … #define CODEC_MODE_MSDIVX … #define CODEC_MODE_ODIVX … #define CODEC_MODE_WAVELET … /* this are the current codec types I want to implement */ /* -> type value in structure */ #define CODEC_TYPE_NONE … #define CODEC_TYPE_L64702 … #define CODEC_TYPE_ZR36050 … #define CODEC_TYPE_ZR36016 … #define CODEC_TYPE_ZR36060 … /* the type of data may be enhanced by future implementations (data-fn.'s) */ /* -> used in command */ #define CODEC_G_STATUS … #define CODEC_S_CODEC_MODE … #define CODEC_G_CODEC_MODE … #define CODEC_S_VFE … #define CODEC_G_VFE … #define CODEC_S_MMAP … #define CODEC_S_JPEG_TDS_BYTE … #define CODEC_G_JPEG_TDS_BYTE … #define CODEC_S_JPEG_SCALE … #define CODEC_G_JPEG_SCALE … #define CODEC_S_JPEG_HDT_DATA … #define CODEC_G_JPEG_HDT_DATA … #define CODEC_S_JPEG_QDT_DATA … #define CODEC_G_JPEG_QDT_DATA … #define CODEC_S_JPEG_APP_DATA … #define CODEC_G_JPEG_APP_DATA … #define CODEC_S_JPEG_COM_DATA … #define CODEC_G_JPEG_COM_DATA … #define CODEC_S_PRIVATE … #define CODEC_G_PRIVATE … #define CODEC_G_FLAG … /* types of transfer, directly user space or a kernel buffer (image-fn.'s) */ /* -> used in get_image, put_image */ #define CODEC_TRANSFER_KERNEL … #define CODEC_TRANSFER_USER … /* ========================= */ /* the structures itself ... */ /* ========================= */ struct vfe_polarity { … }; struct vfe_settings { … }; struct tvnorm { … }; struct jpeg_com_marker { … }; struct jpeg_app_marker { … }; struct videocodec { … }; struct videocodec_master { … }; /* ================================================= */ /* function prototypes of the master/slave interface */ /* ================================================= */ /* attach and detach commands for the master */ // * master structure needs to be kmalloc'ed before calling attach // and free'd after calling detach // * returns pointer on success, NULL on failure struct videocodec *videocodec_attach(struct videocodec_master *master); // * 0 on success, <0 (errno) on failure int videocodec_detach(struct videocodec *codec); /* register and unregister commands for the slaves */ // * 0 on success, <0 (errno) on failure int videocodec_register(const struct videocodec *codec); // * 0 on success, <0 (errno) on failure int videocodec_unregister(const struct videocodec *codec); /* the other calls are directly done via the videocodec structure! */ int videocodec_debugfs_show(struct seq_file *m); #include "zoran.h" static inline struct zoran *videocodec_master_to_zoran(struct videocodec_master *master) { … } static inline struct zoran *videocodec_to_zoran(struct videocodec *codec) { … } #endif /*ifndef __LINUX_VIDEOCODEC_H */
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