- linuxtv.org|Linux DVB API

- -Linux DVB API - -Documentation - - - - - - Dr. - Ralph - Metzler - rjkm@convergence.de - - - - Andreas - Bogk - bogk@convergence.de - - -feb. 7, 2000 -2000convergence -integrated media GmbH - -

Rosenthalerstr. 51, 10178 Berlin

- - linux - dvb - api - documentation - - - -About the Linux DVB API - - - -The Linux DVB API is based on a proposal by Nokia. As a commitment to the -development of terminals based on open standards, Nokia and convergence published -it on linuxtv.org. - - - - Convergence is -the maintainer of the Linux DVB API. Together with the LinuxTV community -(i.e. you, the reader of this document), the Linux DVB API will be constantly -reviewed and improved. With the Linux driver for the Siemens/ Hauppauge DVB PCI -card convergence provides a first implementation of the Linux DVB API. - - - - - - - - - - Introduction - - - - Part of the DVB API builds upon the Video4Linux - (V4L) API. The Siemens DVB card uses the SAA7146 as PCI bridge. A - generic SAA7146 Linux - driver for this chip implements the basic V4L - interface. - - - An older version of the API included the DVB specific calls into - the V4L interface. This turned out to be very cumbersome to - program. Since we also hoped to arrive at a common standard for all - Linux platforms, especially those in embedded consumer devices, we were - happy to find Nokia - as a partner in this effort. They will be using the same API in their - upcoming - - Media Terminal. - - - In the new version of the API only display and grabbing of the - already decompressed images is handled through the V4L device. All - other DVB features like tuning, filtering and playback/recording of the - compressed data stream are accessed through separate devices. - - - A first implementations of the Linux DVB API for the Siemens/ - Hauppauge DVB PCI card is available in the LinuxTV Public - CVS. - - - - - - DVB Devices - - - There are currently 6 DVB devices: Video, Audio, Frontend, SEC, - Demux and CA. The APIs of those devices are described in the - sections below. - - - - DVB Video API - - - The DVB video device controls the MPEG2 video decoder of the DVB hardware. - It can be accessed through /dev/ost/audio. - - - The include file video.h describes the data - types and lists all i/o calls. A complete explanation of all calls can - be found below: - - - - Video API IO control calls - - -

- -int open(const char *deviceName, int flags); - - FUNCTION - - This system call opens a named video device (e.g. /dev/ost/video) for subsequent - use. - When an open() call has succeeded, the device will be ready for use. - The significance of blocking or non-blocking mode is described in the documentation - for functions where there is a difference. It does not affect the semantics of the - open() call itself. A device opened in blocking mode can later be put into non- - blocking mode (and vice versa) using the F_SETFL command of the fcntl system - call. This is a standard system call, documented in the Linux manual page for fcntl. - Only one user can open the Video Device in O_RDWR mode. All other attemts to - open the device in this mode will fail, and an errorcode will be returned. - If the Video Device is opened in O_RDONLY mode, the only ioctl call that can be used - is VIDEO_GET_STATUS. All other call will return an error code. - - - PARAMETERS - - const char *deviceName Name of specific video device. In the current - implementation, /dev/ost/video is the only - one available. - int flags A bit-wise OR of the following flags: - - O_RDONLY read-only access - - O_RDWR read/write access - - O_NONBLOCK open in non-blocking mode - (blocking mode is the default) - RETURNS - - ENODEV Device driver not loaded/available. - - EINTERNAL Internal error, possibly in the communication - with the DVB subsystem. - - EBUSY Device or resource busy. - - EINVAL Invalid argument. - - -

- - - -

- -int close(int fd); - - DESCRIPTION - - This system call closes a previously opened video device - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - RETURNS - - EBADF fd is not a valid open file descriptor - - - -

- - - -

-size_t write(int fd, const void *buf, size_t count); - - DESCRIPTION - - This system call is only provided if VIDEO_SOURCE_MEMORY is selected in the - ioctl call VIDEO_SELECT_SOURCE. The data provided shall be in PES format. - If O_NONBLOCK is not specified the function will block until buffer space - is available. The amount of data to be transferred is implied by count. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - void *buf Pointer to the buffer containing the PES data. - - size_t count Size of buf. - - RETURNS - - EPERM Mode VIDEO_SOURCE_MEMORY not selected. - - ENOMEM Attempted to write more data than the internal buffer can hold. - - EBADF fd is not a valid open file descriptor - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_STOP, boolean mode); - - FUNCTION - - This ioctl call asks the Video Device to stop playing the current stream. - Depending on the input parameter, the screen can be blanked out or - displaying the last decoded frame. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_STOP for this command. - - Boolean mode Indicates how the screen shall be handled. - - TRUE: Blank screen when stop. - FALSE: Show last decoded frame. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EINTERNAL Internal error, possibly in the communication with - the DVB subsystem. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_PLAY); - - FUNCTION - - This ioctl call asks the Video Device to start playing a video stream - from the selected source. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_PLAY for this command. - - - RETURNS - - EBADF fd is not a valid open file descriptor - - EINTERNAL Internal error, possibly in the communication with - the DVB subsystem. - - - -

- - - - -

-int ioctl(int fd, int request = VIDEO_FREEZE); - - FUNCTION - - This ioctl call suspends the live video stream being played. - Decoding and playing are frozen. It is then possible to restart - the decoding and playing process of the video stream using - VIDEO_CONTINUE command. If VIDEO_SOURCE_MEMORY is selected in the - ioctl call VIDEO_SELECT_SOURCE, the DVB-subsystem will not decode - any more data until the ioctl call VIDEO_FREEZE or VIDEO_PLAY is - performed. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_FREEZE for this command. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error, possibly in the communication with - the DVB subsystem. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_CONTINUE); - - FUNCTION - - This ioctl call restarts decoding and playing processes of the video - stream which was played before a call to VIDEO_FREEZE was made. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_CONTINUE for this command. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error, possibly in the communication with - the DVB subsystem. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_SELECT_SOURCE, videoStreamSource_t source); - - FUNCTION - - This ioctl call informs the video device which source shall be used - for the input data. The possible sources are demux or memory. If - internal is selected, the data is feed to the Video Device through - the write command. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_SELECT_SOURCE for this command. - - videoStreamSource_t source - Indicates which source shall be used for the Video stream. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error, possibly in the communication with - the DVB subsystem. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_SET_BLANK, boolean mode); - - DESCRIPTION - - This ioctl call asks the Video Device to blank out the picture. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_SET_BLANK for this command. - - boolean mode TRUE: Blank screen when stop. - FALSE: Show last decoded frame. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EINVAL Illegal input parameter. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_GET_STATUS, struct videoStatus *status); - - DESCRIPTION - - This ioctl call asks the Video Device to return the current status of the device. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_GET_STATUS for this command. - - struct videoStatus Returns the current status of the Video Device. - *status - - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EFAULT status points to invalid address - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_GET_EVENT, struct videoEvent *ev); - - DESCRIPTION - - This ioctl call returns an event of type videoEvent if available. - If an event is not available, the behavior depends on whether the device is in - blocking or non-blocking mode. In the latter case, the call fails immediately - with errno set to EWOULDBLOCK. In the former case, the call blocks until an - event becomes available. - The standard Linux poll() and/or select() system calls can be used with the - device file descriptor to watch for new events. For select(), the file - descriptor should be included in the exceptfds argument, and for poll(), - POLLPRI should be specified as the wake-up condition. - Read-only permissions are sufficient for this ioctl call. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_GET_EVENT for this command. - - struct videoEvent *ev Points to the location where the event, if any, is - to be stored. - - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT ev points to invalid address - - EWOULDBLOCK There is no event pending, and the device is in - non-blocking mode. - - EBUFFEROVERFLOW Overflow in event queue - one or more events were lost. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_SET_DISPLAY_FORMAT, videoDisplayFormat_t format); - - DESCRIPTION - - This ioctl call asks the Video Device to select the video format to be applied - by the MPEG chip on the video. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_SET_DISPLAY_FORMAT for this command. - - videoDisplayFormat_t Selects the video format to be used. - format - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EINVAL Illegal parameter format. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_STILLPICTURE, struct videoDisplayStillPicture *sp); - - DESCRIPTION - - This ioctl call asks the Video Device to display a still picture (I-frame). - The input data shall contain an I-frame. If the pointer is NULL, then the - current displayed still picture is blanked. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_STILLPICTURE for this command. - - struct videoDisplayStillPicture *sp Pointer to a location where an I-frame - and size is stored. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EFAULT sp points to an invalid iframe. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_FAST_FORWARD, int nFrames); - - DESCRIPTION - - This ioctl call asks the Video Device to skip decoding of N number of I-frames. - This call can only be used if VIDEO_SOURCE_INTRENAL is selected. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_FAST_FORWARD for this command. - - int nFrames The number of frames to skip. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EPERM Mode VIDEO_SOURCE_MEMORY not selected. - - EINVAL Illegal parameter format. - - - -

- - - -

- -int ioctl(int fd, int request = VIDEO_SLOWMOTION, int nFrames); - - DESCRIPTION - - This ioctl call asks the Video Device to repeat decoding frames N number of times. - This call can only be used if VIDEO_SOURCE_MEMORY is selected. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals VIDEO_SLOWMOTION for this command. - - int nFrames The number of frames to skip. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EPERM Mode VIDEO_SOURCE_MEMORY not selected. - - EINVAL Illegal parameter format. - -

- - - - - - - - DVB Audio API - - The DVB audio device controls the MPEG2 audio decoder of the - DVB hardware. It can be accessed through /dev/ost/audio. - - - The function calls defined in the include file audio.h are described in - detail below: - - - - Audio API IO control calls - - -

- -int open(const char *deviceName, int flags); - - DESCRIPTION - - This system call opens a named audio device (e.g. /dev/ost/audio) for subsequent - use. When an open() call has succeeded, the device will be ready for use. - The significance of blocking or non-blocking mode is described in the - documentation for functions where there is a difference. It does not affect - the semantics of the open() call itself. A device opened in blocking mode can - later be put into non-blocking mode (and vice versa) using the F_SETFL command - of the fcntl system call. This is a standard system call, documented in the - Linux manual page for fcntl. - Only one user can open the Audio Device in O_RDWR mode. All other attempts to - open the device in this mode will fail, and an errorcode will be returned. - If the Audio Device is opened in O_RDONLY mode, the only ioctl call that can - be used is AUDIO_GET_STATUS. All other call will return with an error code. - - - PARAMETERS - - const char *deviceName Name of specific audio device. - - int flags A bit-wise OR of the following flags: - - O_RDONLY read-only access - - O_RDWR read/write access - - O_NONBLOCK open in non-blocking mode - (blocking mode is the default) - - RETURNS - - ENODEV Device driver not loaded/available. - - EINTERNAL Internal error - - EBUSY Device or resource busy. - - EINVAL Invalid argument. - - - -

- - - -

- -int close(int fd); - - DESCRIPTION - - This system call closes a previously opened audio device - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - RETURNS - - EBADF fd is not a valid open file descriptor - - - -

- - - -

- -size_t write(int fd, const void *buf, size_t count); - - DESCRIPTION - - This system call can only be used if AUDIO_SOURCE_MEMORY is selected in the - ioctl call AUDIO_SELECT_SOURCE. The data provided shall be in PES format. - If O_NONBLOCK is not specified the function will block until buffer space is - available. The amount of data to be transferred is implied by count. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - void *buf Pointer to the buffer containing the PES data. - - size_t count Size of buf. - - RETURNS - - EPERM Mode VIDEO_SOURCE_INTERNAL not selected. - - ENOMEM Attempted to write more data than the internal - buffer can hold. - - EBADF fd is not a valid open file descriptor - - - -

- - - -

- -int ioctl(int fd, int request = AUDIO_STOP); - - DESCRIPTION - - This ioctl call asks the Audio Device to stop playing the current stream. - - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_STOP for this command. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EINTERNAL Internal error - - - -

- - - -

- -int ioctl(int fd, int request = AUDIO_PLAY); - - DESCRIPTION - - This ioctl call asks the Audio Device to start playing an audio stream from the - selected source. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_PLAY for this command. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - - -

- - - -

- -int ioctl(int fd, int request = AUDIO_PAUSE); - - DESCRIPTION - - This ioctl call suspends the audio stream being played. Decoding and playing are - paused. It is then possible to restart again decoding and playing process of the - audio stream using AUDIO_CONTINUE command. - If AUDIO_SOURCE_MEMORY is selected in the ioctl call AUDIO_SELECT_SOURCE, the - DVB-subsystem will not decode (consume) any more data until the ioctl call - AUDIO_CONTINUE or AUDIO_PLAY is performed. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_PAUSE for this command. - - RETURNS - - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - - -

- - - -

- -int ioctl(int fd, int request = AUDIO_CONTINUE); - - DESCRIPTION - - This ioctl call restarts decoding and playing processes of the audio stream, - which was played before, a call to AUDIO_PAUSE was made. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_CONTINUE for this command. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error, possibly in the communication - with the DVB subsystem. - - - -

- - - -

- -int ioctl(int fd, int request = AUDIO_SELECT_SOURCE, audioStreamSource_t source); - - DESCRIPTION - - This ioctl call informs the audio device which source shall be used for the - input data. The possible sources are demux or memory. If AUDIO_SOURCE_MEMORY - is selected, the data is fed to the Audio Device through the write command. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_SELECT_SOURCE for this command. - - audioStreamSource_t source Indicates the source that shall be used for the - Audio stream. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - - -

- - - -

- -int ioctl(int fd, int request = AUDIO_SET_MUTE, boolean state); - - DESCRIPTION - - This ioctl call asks the audio device to mute the stream that is currently being - played. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_SET_MUTE for this command. - - boolean state Indicates if audio device shall mute or not. - TRUE Audio Mute - FALSE Audio Unmute - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error, - - EINVAL Illegal input parameter. - -

- - - -

-int ioctl(int fd, int request = AUDIO_SET_AV_SYNC, boolean state); - - DESCRIPTION - - This ioctl call asks the Audio Device to turn ON or OFF A/V synchronisation. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_AV_SYNC for this command. - - boolean state Tells the DVB subsystem if A/V synchronisation shall be ON or OFF. - TRUE AV-sync ON - FALSE AV-sync OFF - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EINVAL Illegal input parameter. - - - -

- - - -

- -int ioctl(int fd, int request = AUDIO_SET_BYPASS_MODE, boolean mode); - - DESCRIPTION - - This ioctl call asks the Audio Device to bypass the Audio decoder and forward - the stream without decoding. This mode shall be used if streams that can't be - handled by the DVB system shall be decoded. Dolby DigitalTM streams are - automatically forwarded by the DVB subsystem. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_SET_BYPASS_MODE for this command. - - boolean mode Enables or disables the decoding of the current - Audio stream in the DVB subsystem. - TRUE Bypass is disabled - FALSE Bypass is enabled - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EINVAL Illegal pointer mode. - - -

- - - -

-int ioctl(int fd, int request = AUDIO_CHANNEL_SELECT, audioChannelSelect_t) - - DESCRIPTION - - This ioctl call asks the Audio Device to select the requested channel if possible. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_CHANNEL_SELECT for this command. - - audioChannelSelect_t ch Select the output format of the audio (Mono, stereo) - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EINVAL Illegal pointer ch. - - - -

- - - -

- -int ioctl(int fd, int request = AUDIO_GET_STATUS, struct audioStatus *status) - - DESCRIPTION - - This ioctl call asks the Audio Device to return the current state of the Audio - Device. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals AUDIO_GET_STATUS for this command. - - struct audioStatus *status Returns the current state of Audio Device - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EINTERNAL Internal error - - EFAULT status points to invalid address - - - -

- - - - - - - - DVB Frontend API - - - The DVB frontend device controls the frontend of the DVB hardware, e.g. - tuning, symbol rate, error correction, ... - It is accessed through /dev/ost/qpskfe. - - - The function calls defined in the include file frontend.h are described - in detail below: - - - - Frontend API IO control calls - - -

- -int open(const char *deviceName, int flags); - - DESCRIPTION - - This system call opens a named front-end device (e.g. /dev/qpskfe) for - subsequent use. The device can be opened in read-only mode, which only allows - monitoring of device status and statistics, or read/write mode, which allows - any kind of use (e.g. performing tuning operations.) - - In a system with multiple front-ends, it is usually the case that multiple - devices cannot be open in read/write mode simultaneously. As long as a - front-end device is opened in read/write mode, other open() calls in - read/write mode will either fail or block, depending on whether - non-blocking or blocking mode was specified. - A front-end device opened in blocking mode can later be put into non-blocking - mode (and vice versa) using the F_SETFL command of the fcntl system call. - This is a standard system call, documented in the Linux manual page for fcntl. - When an open() call has succeeded, the device will be ready for use in the - specified mode. This implies that the corresponding hardware is powered up, - and that other front-ends may have been powered down to make that possible. - - PARAMETERS - - const char *deviceName I Name of specific front-end device. In the - current implementation, /dev/qpskfe is the - only one available (QPSK satellite front-end.) - - int flags I A bit-wise OR of the following flags: - O_RDONLY read-only access - O_RDWR read/write access - O_NONBLOCK open in non-blocking mode - (blocking mode is the default) - RETURNS - - ENODEV Device driver not loaded/available. - - EBUSY Device or resource busy. - - EINVAL Invalid argument. - - - -

- - - -

- -int close(int fd); - - DESCRIPTION - - This system call closes a previously opened front-end device. After closing a - front-end device, its corresponding hardware might be powered down - automatically, but only when this is needed to open another front-end device. - To affect an unconditional power down, it should be done explicitly using - the OST_SET_POWER_STATE ioctl. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - RETURNS - - EBADF fd is not a valid open file descriptor - - - -

- - - -

- -int ioctl(int fd, int request = OST_SELFTEST); - - DESCRIPTION - - This ioctl call initiates an automatic self-test of the front-end hardware. - This call requires read/write access to the device. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals OST_SELFTEST for this command. - - RETURNS - - 0 Success - - -1 Failure - - - -

- - - -

- -int ioctl(int fd, int request = OST_SET_POWER_STATE, uint32_t state); - - DESCRIPTION - - This ioctl call, implemented in many OST device drivers, enables direct - control over the power state of the hardware device, which may be on, off, - standby, or suspend. The latter two are low-power modes, which disable all - functionality of the device until turned on again. In contrast to the off - state, however, the standby and suspend states resume operation in the same - state as when the device was active. The only difference between the standby - and suspend states is a different tradeoff between resume time and power - consumption. Power consumption may be lower in the suspend state at the - cost of a longer resume time. - - A device that implements this call does not necessarily support two low-power - modes. If it only support one low-power state, or none at all, the - OST_SET_POWER_STATE operation for the missing states will still succeed, but - it will be mapped to an existing state as per this table: - - number of low-power requested state resulting state - states supported - - 1 standby suspend - - 1 suspend suspend - - 0 standby on - - 0 suspend on - - For other cases where a required state is missing, an error code will be - returned. This can happen if a device does not support the power-off state, - but nevertheless implements this ioctl operation for control of low-power - states. - When opening a device in read/write mode, the driver ensures that the - corresponding hardware device is turned on initially. If the device is - later turned off or put in suspend mode, it has to be explicitly turned on - again. - - This call requires read/write access to the device. (Note that the power - management driver can affect the power state of devices without using this - ioctl operation, so having exclusive read/write access to a device does not - imply total control over the power state.) - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals OST_SET_POWER_STATE for this command. - - uint32_t state I Requested power state. One of: - - OST_POWER_ON: turn power on - OST_POWER_STANDBY: set device in standby mode - OST_POWER_SUSPEND: set device in suspend mode - OST_POWER_OFF: turn power off - - - RETURNS - - EBADF fd is not a valid open file descriptor - - EINVAL illegal state, or not available on this device - - EPERM permission denied (needs read/write access) - - ENOSYS Function not available for this device. - - - -

- - - -

- -int ioctl(int fd, int request = OST_GET_POWER_STATE, uint32_t *state); - - DESCRIPTION - - This ioctl call, implemented in many OST device drivers, obtains the power - state of the hardware device, which may be on, off, standby, or suspend. - A device that implements this call does not necessarily support all four states. - If there is only one low-power state, the suspend state will be returned for - that state. If there is no low-power state, the on state will be reported - standby and suspend states will be equivalent to the on state. - For this command, read-only access to the device is sufficient. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals OST_GET_POWER_STATE for this command. - - uint32_t *state O Pointer to a variable where the power state is - to be stored. Possible values are: - OST_POWER_ON power is on - OST_POWER_STANDBY device in - standby mode - OST_POWER_SUSPEND: device in - suspend mode - OST_POWER_OFF: power is off - - - RETURNS - - EBADF fd is not a valid open file descriptor - - EINVAL illegal state, or not available on this device - - EFAULT state points to invalid address - - EPERM permission denied (needs read/write access) - - ENOSYS Function not available for this device. - - - -

- - - -

- -int ioctl(int fd, int request = QPSK_READ_STATUS, feStatus *status); - - DESCRIPTION - - This ioctl call returns status information about the front-end. - This call only requires read-only access to the device. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals FE_READ_STATUS for this command. - - struct feStatus *status O Points to the location where the front-end - status word is to be stored. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT status points to invalid address - - - -

- - - -

- -int ioctl(int fd, int request = FE_READ_BER, uint32_t *ber); - - DESCRIPTION - - This ioctl call returns the bit error rate for the signal currently - received/demodulated by the front-end. For this command, read-only access - to the device is sufficient. - - FUNCTION PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals FE_READ_BER for this command. - - uint32_t *ber O The bit error rate, as a multiple of 10-9, is stored into *ber. - - Example: a value of 2500 corresponds to a bit error - rate of 2.5 10-6, or 1 error in 400000 bits. - - RETURNS - - EBADF fd is not a valid open file descriptor. - - EFAULT ber points to invalid address - - ENOSIGNAL There is no signal, thus no meaningful bit error - rate. Also returned if the front-end is not turned on. - - ENOSYS Function not available for this device. - - - -

- - - -

- -int ioctl( int fd, int request = FE_READ_SIGNAL_STRENGTH, int32_t *strength); - - DESCRIPTION - - This ioctl call returns the signal strength value for the signal currently - received by the front-end. For this command, read-only access to the device - is sufficient. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals FE_READ_SIGNAL_STRENGTH for this - command. - int32_t *strength O The signal strength value, as a multiple of 10^-6 dBm, - is stored into *strength. - Example: a value of -12,500,000 corresponds to a signal - strength value of -12.5 dBm. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT strength points to invalid address - - ENOSIGNAL There is no signal, thus no meaningful signal - strength value. Also returned if front-end is not - turned on. - - ENOSYS Function not available for this device. - - - -

- - - -

- -int ioctl(int fd, int request = FE_READ_SNR, int32_t *snr); - - DESCRIPTION - - This ioctl call returns the signal-to-noise ratio for the signal currently - received by the front-end. For this command, read-only access to the device - is sufficient. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals FE_READ_SNR for this command. - - int32_t *snr O The signal-to-noise ratio, as a multiple of - 10^-6 dB, is stored into *snr. - - Example: a value of 12,300,000 corresponds - to a signal-to-noise ratio of 12.3 dB. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT snr points to invalid address - - ENOSIGNAL No stable signal, thus no meaningful signal-to- - noise ratio. Also returned if front-end is not - turned on. - - ENOSYS Function not available for this device. -

- - - -

-int ioctl( int fd, int request = FE_READ_UNCORRECTED_BLOCKS, uint32_t *ublocks); - - - DESCRIPTION - - This ioctl call returns the number of uncorrected blocks detected by the device - driver during its lifetime. For meaningful measurements, the increment in - block count during a specific time interval should be calculated2. For this - command, read-only access to the device is sufficient. - - 2 Note that the counter will wrap to zero after its maximum count has - been reached (232-1). - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals FE_READ_UNCORRECTED_BLOCKS for this command. - - uint32_t *ublocks O The total number of uncorrected blocks seen - by the driver so far. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT ublocks points to invalid address - - ENOSYS Function not available for this device. - - - -

- - - -

- -int ioctl( int fd, int request = FE_GET_NEXT_FREQUENCY, uint32_t *freq); - - DESCRIPTION - - When scanning a frequency range, it is desirable to use a scanning step size - that is as large as possible, yet small enough to be able to lock to any signal - within the range. - This ioctl operation does just that - it increments a given frequency by a - step size suitable for efficient3 scanning. - The step size used by this function may be a quite complex function of the given - frequency, hardware capabilities, and parameter settings of the device. Thus, a - returned result is only valid for the current state of the device. - For this command, read-only access to the device is sufficient. - - 3 Note that scanning may still be excruciatingly slow on some hardware, for - other reasons than a non-optimal scanning step size. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals FE_GET_NEXT_FREQUENCY for this command. - - uint32_t *freq I/O Input: a given frequency - Output: the frequency corresponding to - the next higher frequency setting. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT freq points to invalid address - - EINVAL maximum frequency reached - - ENOSYS Function not available for this device. - - - -

- - - -

- -int ioctl( int fd, int request = FE_GET_NEXT_SYMBOL_RATE, uint32_t *symbolRate); - - DESCRIPTION - - When scanning a range of symbol rates (e.g. for "blind acquisition") it is - desirable to use a scanning step size that is as large as possible, yet - small enough to detect any valid signal within the range. This ioctl - operation does just that - it increments a given symbol rate by a step size - suitable for efficient4 scanning. - The step size used by this function may be a quite complex function of the given - symbol rate, hardware capabilities, and parameter settings of the device. - Thus, a returned result is only valid for the current state of the device. - For this command, read-only access to the device is sufficient. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals FE_GET_NEXT_SYMBOL_RATE for this command. - - uint32_t *symbolRate I/O Input: a given symbol rate - Output: the symbol rate corresponding to the next higher symbol rate setting. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT symbolRate points to invalid address - - EINVAL maximum symbol rate reached - - ENOSYS Function not available for this device. - - - -

- - - -

- -int ioctl(int fd, int request = QPSK_TUNE, struct qpskParameters *p); - - DESCRIPTION - - This ioctl call starts a tuning operation using specified parameters. - The result of this call will be successful if the parameters were valid and - the tuning could be initiated. - The result of the tuning operation in itself, however, will arrive - asynchronously as an event (see documentation for QPSK_GET_EVENT and qpskEvent.) - If a new QPSK_TUNE operation is initiated before the previous one was completed, - the previous operation will be aborted in favor of the new one. - This command requires read/write access to the device. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request Equals QPSK_TUNE for this command. - - struct qpskParameters *p Points to parameters for tuning operation. - - RETURNS - - EBADF fd is not a valid open file descriptor - EFAULT p points to invalid address - EINVAL parameter value(s) not valid - - - -

- - - -

- -int ioctl(int fd, int request = QPSK_GET_EVENT, struct qpskEvent *ev); - - DESCRIPTION - - This ioctl call returns an event of type qpskEvent if available. If an event - is not available, the behavior depends on whether the device is in blocking - or non-blocking mode. In the latter case, the call fails immediately with - errno set to EWOULDBLOCK. In the former case, the call blocks until an event - becomes available. - The standard Linux poll() and/or select() system calls can be used with the - device file descriptor to watch for new events. For select(), the file - descriptor should be included in the exceptfds argument, and for poll(), - POLLPRI should be specified as the wake-up condition. - Since the event queue allocated is rather small (room for 8 events), the queue - must be serviced regularly to avoid overflow. If an overflow happens, the - oldest event is discarded from the queue, and an error (EBUFFEROVERFLOW) occurs - the next time the queue is read. After reporting the error condition in this - fashion, subsequent QPSK_GET_EVENT calls will return events from the queue as - usual. - For the sake of implementation simplicity, this command requires read/write - access to the device. - - PARAMETERS - - int fd File descriptor returned by a previous call to open(). - - int request I Equals QPSK_GET_EVENT for this command. - - struct qpskEvent *ev O Points to the location where the event, if any, is to be stored. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT ev points to invalid address - - EWOULDBLOCK There is no event pending, and the device is in - non-blocking mode. - - EBUFFEROVERFLOW Overflow in event queue - one or more events were lost. - - - -

- - - -

- -int ioctl(int fd, int request = QPSK_FE_INFO, struct qpskFrontendInfo *info); - - DESCRIPTION - - This ioctl call returns information about the front-end. - This call only requires read-only access to the device. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals QPSK_FE_INFO for this command. - - struct qpskFrontendInfo *info O Points to the location where the front-end - information is to be stored. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT info points to invalid address - - - -

- - - -

- -int ioctl(int fd, int request = QPSK_WRITE_REGISTER, struct qpskRegister *reg); - - DESCRIPTION - - This ioctl call is intended for hardware-specific diagnostics. It writes - an 8-bit value at an 8-bit address of a register in a chip identified by an - 8-bit index. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals QPSK_WRITE_REGISTER for this command. - - struct qpskRegister *reg I Specifies a value that should be written - into a specified register in a specified chip. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT reg points to and invalid address - - EINVAL Register specification invalid. - - - - -

- - - -

- -int ioctl(int fd, int request = QPSK_READ_REGISTER, struct qpskRegister *reg); - - DESCRIPTION - - This ioctl call is intended for hardware-specific diagnostics. - It reads an 8-bit value at an 8-bit address of a register in a chip - identified by an 8-bit index. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals QPSK_READ_REGISTER for this command. - - struct qpskRegister *reg I/O I: specifies a register in a specified - chip from which a value should be read. - - O: the value is read into the - qpskRegister structure. - - RETURNS - - EBADF fd is not a valid open file descriptor - - EFAULT reg points to and invalid address - - EINVAL Register specification invalid. - - - -

- - - - - - - - DVB SEC API - - - The DVB SEC device controls the Satellite Equipment Control of - the DVB hardware, i.e. DiSEqC and V-SEC. - It is accessed through /dev/ost/sec. - - - The function calls defined in the include file sec.h aredescribed in detail - below: - - - - SEC API IO control calls - - -

- -int open(const char *deviceName, int flags); - - DESCRIPTION - - This system call opens a named SEC device for subsequent use. - If the device is opened in read-only mode, only status and statistics - monitoring is allowed. If the device is opened in read/write mode, all - types of operations can be performed. - Any number of applications can have simultaneous access to the device. - - PARAMETERS - - const char *deviceName I Name of the SEC device. - - int flags I Valid values are: - O_RDONLY read-only access - O_RDWR read/write access - - The optional flag O_NONBLOCK is not supported. If O_NONBLOCK is set, - open() and most other subsequent calls to the device will return -1 and - set errno to EWOULDBLOCK. - The communication with the peripheral devices is sequential by nature, - so it is probably preferable to use the device in synchronous mode. - This is the motivation for not going through the extra effort of - implementing asynchronous operation of the device. - - RETURNS - - ENODEV Device not loaded/available - EFAULT deviceName does not refer to a valid memory area. - EINVAL Invalid argument - - - -

- - - -

- -int close(int fd); - - DESCRIPTION - - This system call closes a previously opened SEC device. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - RETURNS - - EBADF fd is not a valid file descriptor. - - - -

- - - -

- -int ioctl(int fd, int request = SEC_GET_STATUS, struct secStatus* status); - - DESCRIPTION - - This call gets the status of the device. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals SEC_GET_STATUS for this command. - - struct secStatus* status O The status of the device. - - RETURNS - - ENODEV Device driver not loaded/available - - EFAULT status is an invalid pointer - - EBUSY Device or resource busy - - EINVAL Invalid argument - - EPERM File not opened with read permissions - - EINTERNAL Internal error in the device driver - - - -

- - - -

- -int ioctl(int fd, int request = SEC_RESET_OVERLOAD); - - DESCRIPTION - - If the bus has been automatically powered off due to power overload, this - ioctl call restores the power to the bus. The call requires read/write - access to the device. - This call has no effect if the device is manually powered off. - - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals SEC_RESET_OVERLOAD for this command. - - RETURNS - - EBADF fd is not a valid file descriptor. - - EPERM Permission denied (needs read/write access) - - EINTERNAL Internal error in the device driver - - - -

- - - -

- -int ioctl(int fd, int request = SEC_SEND_SEQUENCE, struct secCmdSequence *seq); - - DESCRIPTION - - This ioctl call is used to send a sequence of DiSEqCTM and/or V-SEC - commands. The first version of the SEC device does not support V-SEC - signalling and it aborts the operation with an error code if a V-SEC - command is detected in the input data. - - ! The call will fail with errno set to EBUSOVERLOAD if the bus is - overloaded. If the bus is overloaded, SEC_RESET_OVERLOAD can be - called and the operation can be retried. - - ! If seq.numCommands equals 0 and seq.miniCommand equals SEC_MINI_NONE, - the bus voltage will be switched and the continuous 22kHz tone - generation enabled/disabled immediately. - - This operation is atomic. If several processes calls this ioctl - simultaneously, the operations will be serialised so a complete sequence - is sent at a time. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals SEC_SEND_SEQUENCE for this command. - - struct secCmdSequence *seq I Pointer to the command sequence to be transmitted. - - RETURNS - - EBADF Fd is not a valid file descriptor. - - EFAULT Seq points to an invalid address. - - EINVAL The data structure referred to by seq is invalid in - some way. - - EPERM Permission denied (needs read/write access) - - EINTERNAL Internal error in the device driver - - - EBUSMODE The device is not prepared for transmission - (e.g. it might be manually powered off). - - EBUSOVERLOAD Bus overload has occurred. - - - -

- - - -

- -int ioctl(int fd, int request = SEC_SET_TONE, secToneMode tone); - - DESCRIPTION - - This call is used to set the generation of the continuous 22kHz tone. - The possibility to just change the tone mode is already provided by - ioctl SEC_SEND_SEQUENCE, but SEC_SET_TONE is an easier to use interface. - To keep the transmission of a command sequence (see section 4.4.5 ) as - an atomic operation, SEC_SET_TONE will block if a transmission is in - progress. This call requires read/write permissions. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals SEC_SET_TONE for this command. - - secToneMode tone I The requested tone generation mode (on/off). - - RETURNS - - ENODEV Device driver not loaded/available - - EBUSY Device or resource busy - - EINVAL Invalid argument - - EPERM File not opened with read permissions - - EINTERNAL Internal error in the device driver - - - -

- - - -

- -int ioctl(int fd, int request = SEC_SET_VOLTAGE, secVoltage voltage); - - DESCRIPTION - - This call is used to set the bus voltage. The possibility to just change - the bus voltage is already provided by ioctl SEC_SEND_SEQUENCE, but - SEC_SET_VOLTAGE is an easier to use interface. - To keep the transmission of a command sequence (see section 4.4.5 ) as - an atomic operation, SEC_SET_VOLTAGE will block if a transmission is in - progress. - This call requires read/write permissions. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals SEC_SET_VOLTAGE for this command. - - secVoltage voltage I The requested bus voltage. - - RETURNS - - ENODEV Device driver not loaded/available - - EBUSY Device or resource busy - - EINVAL Invalid argument - - EPERM File not opened with read permissions - - EINTERNAL Internal error in the device driver - - - -

- - - - - - - - DVB Demux API - - - The DVB demux device lets you set TS, PID and section filters in the DVB - device. This is internally accomplished through calls to the - demux kernel module. - The demux device can be accessed through /dev/ost/demux. - - - The function calls defined in the include file dmx.h are described in detail - below: - - - - Demux API IO control calls - - -

- -int open(const char *deviceName, int flags); - - DESCRIPTION - - This system call, used with a device name of /dev/ost/demuxn, where n - denotes the specific demux device to be opened, allocates a new filter - and returns a handle which can be used for subsequent control of that - filter. This call has to be made for each filter to be used, i.e. every - returned file descriptor is a reference to a single filter. - /dev/ost/dvrn is a logical device to be used for retrieving Transport - Streams for digital video recording. n identifies the physical demux - device that provides the actual DVR functionlaity. When reading from - this device a transport stream containing the packets from all PES - filters set in the corresponfing demux device (/dev/osst/demuxn) - having the output set to DMX_OUT_TS_TAP. A recorded Transport Stream - is replayed by writing to this device. - This device can only be opened in read-write mode. - The significance of blocking or non-blocking mode is described in the - documentation for functions where there is a difference. It does not - affect the semantics of the open() call itself. A device opened in - blocking mode can later be put into non-blocking mode - (and vice versa) using the F_SETFL command of the fcntl system call. - - - PARAMETERS - - const char *deviceName I Name of the demux device, which should be - /dev/ost/demuxn where n denotes the - specific demux device to be opened, or the - name of a logical DVR device, /dev/ost/dvrn. - - int flags I A bit-wise OR of the following flags: - O_RDWR read/write access. - O_NONBLOCK open in non-blocking mode - (blocking mode is the default). - - RETURNS - - ENODEV Device driver not loaded/available. - - EINVAL Invalid argument. - - EMFILE "Too many open files", i.e. no more filters available. - - ENOMEM The driver failed to allocate enough memory. - - - -

- - - -

- -int close(int fd); - - DESCRIPTION - - This system call deactivates and deallocates a filter that was previously - allocated via the open() call. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - RETURNS - - EBADF fd is not a valid open file descriptor - - - -

- - - -

- -size_t read(int fd, void *buf, size_t count); - - DESCRIPTION - - This system call returns filtered data, which might be section or PES - data. The filtered data is transferred from the driver's internal circular - buffer to buf. The maximum amount of data to be transferred is implied by - count. - - When returning section data the driver always tries to return a complete - single section (even though buf would provide buffer space for more data). - If the size of the buffer is smaller than the section as much as possible - will be returned, and the remaining data will be provided in subsequent - calls. - The size of the internal buffer is 2 * 4096 bytes (the size of two maximum - sized sections) by default. The size of this buffer may be changed by - using the DMX_SET_BUFFER_SIZE function. If the buffer is not large enough, - or if the read operations are not performed fast enough, this may result - in a buffer overflow error. In this case EBUFFEROVERFLOW will be returned, - and the circular buffer will be emptied. - This call is blocking if there is no data to return, i.e. the process - will be put to sleep waiting for data, unless the O_NONBLOCK flag is - specified. - Note that in order to be able to read, the filtering process has to be - started by defining either a section or a PES filter by means of the - ioctl functions, and then starting the filtering process via the DMX_START - ioctl function or by setting the DMX_IMMEDIATE_START flag. - If the reading is done from a logical DVR demux device, the data will - constitute a Transport Stream including the packets from all PES filters - in the corresponding demux device /dev/ost/demuxn having the output set - to DMX_OUT_TS_TAP. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - void *buf O Pointer to the buffer to be used for returned filtered data. - - size_t count I Size of buf. - - RETURNS - - EWOULDBLOCK No data to return and O_NONBLOCK was specified. - - EBADF fd is not a valid open file descriptor - - ECRC Last section had a CRC error - no data - returned. The buffer is flushed. - - EBUFFEROVERFLOW The filtered data was not read from the buffer in - due time, resulting in non-read data being lost. - The buffer is flushed. - - ETIMEDOUT The section was not loaded within the stated - timeout period. See ioctl DMX_SET_FILTER for - how to set a timeout. - - EFAULT The driver failed to write to the callers buffer - due to an invalid *buf pointer. - - - -

- - - -

- -ssize_t write(int fd, const void *buf, size_t count); - - DESCRIPTION - - This system call is only provided by the logical device /dev/ost/dvrn, - where n identifies the physical demux device that provides the actual - DVR functionality. It is used for replay of a digitally recorded - Transport Stream. Matching filters have to be defined in the - corresponding physical demux device, /dev/ost/demuxn. - The amount of data to be transferred is implied by count. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - void *buf I Pointer to the buffer containing the Transport Stream. - - size_t count I Size of buf. - - RETURNS - - EWOULDBLOCK No data was written. This might happen if - O_NONBLOCK was specified and there is no more - buffer space available (if O_NONBLOCK is not - specified the function will block until buffer - space is available). - - EBUSY This error code indicates that there are - conflicting requests. The corresponding demux - device is setup to receive data from the front- - end. Make sure that these filters are stopped - and that the filters with input set to DMX_IN_DVR - are started. - - EBADF fd is not a valid open file descriptor - - - -

- - - -

- -int ioctl( int fd, int request = DMX_START); - - DESCRIPTION - - This ioctl call is used to start the actual filtering operation - defined via the ioctl calls DMX_SET_FILTER or DMX_SET_PES_FILTER. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals DMX_START for this command. - - RETURNS - - EBADF fd is not a valid file descriptor - - EINVAL Invalid argument, i.e. no filtering parameters - provided via the DMX_SET_FILTER or - DMX_SET_PES_FILTER functions. - - EBUSY This error code indicates that there are - conflicting requests. There are active filters - filtering data from another input source. Make - sure that these filters are stopped before starting - this filter. - - - -

- - - -

- -int ioctl( int fd, int request = DMX_STOP); - - DESCRIPTION - - This ioctl call is used to stop the actual filtering operation defined - via the ioctl calls DMX_SET_FILTER or DMX_SET_PES_FILTER and started via - the DMX_START command. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals DMX_STOP for this command. - - RETURNS - - EBADF fd is not a valid file descriptor - -

- - - -

- -int ioctl( int fd, int request = DMX_SET_FILTER, struct dmxSctFilterParams *params); - - DESCRIPTION - - This ioctl call sets up a filter according to the filter and mask - parameters provided. A timeout may be defined stating number of seconds - to wait for a section to be loaded. A value of 0 means that no timeout - should be applied. Finally there is a flag field where it is possible to - state whether a section should be CRC-checked, whether the filter should - be a "one-shot" filter, i.e. if the filtering operation should be stopped - after the first section is received, and whether the filtering operation - should be started immediately (without waiting for a DMX_START ioctl call). - If a filter was previously set-up, this filter will be cancelled, and the - receive buffer will be flushed. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals DMX_SET_FILTER for this command. - - struct I Pointer to structure containing filter - - dmxSctFilterParams parameters. - *params - - RETURNS - - EBADF fd is not a valid file descriptor - - EINVAL Invalid argument. - -

- - - -

- -int ioctl( int fd, int request = DMX_SET_PES_FILTER, struct dmxPesFilterParams *params); - - DESCRIPTION - - This ioctl call sets up a PES filter according to the parameters provided. - By a PES filter is meant a filter that is based just on the packet - identifier (PID), i.e. no PES header or payload filtering capability is - supported. - The transport stream destination for the filtered output may be set. Also - the PES type may be stated in order to be able to e.g. direct a video - stream directly to the video decoder. Finally there is a flag field where - it is possible to state whether the filtering operation should be started - immediately (without waiting for a DMX_START ioctl call). - If a filter was previously set-up, this filter will be cancelled, and the - receive buffer will be flushed. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals DMX_SET_PES_FILTER for this command. - - struct I Pointer to structure containing filter - - dmxPesFilterParams parameters. - *params - - RETURNS - - EBADF fd is not a valid file descriptor - - EINVAL Invalid argument. - - EBUSY This error code indicates that there are - conflicting requests. There are active filters - filtering data from another input source. Make - sure that these filters are stopped before starting - this filter. - - - -

- - - -

- -int ioctl( int fd, int request = DMX_SET_BUFFER_SIZE, unsigned long size); - - DESCRIPTION - - This ioctl call is used to set the size of the circular buffer used - for filtered data. The default size is two maximum sized sections, i.e. - if this function is not called a buffer size of 2 * 4096 bytes will be - used. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals DMX_SET_BUFFER_SIZE for this command. - - unsigned long size I Size of circular buffer. - - RETURNS - - EBADF fd is not a valid file descriptor. - - ENOMEM The driver was not able to allocate a buffer of the requested size. - - - -

- - - -

- -int ioctl( int fd, int request = DMX_GET_EVENT, struct dmxEvent *ev); - - DESCRIPTION - - This ioctl call returns an event if available. If an event is not - available, the behavior depends on whether the device is in blocking or - non-blocking mode. In the latter case, the call fails immediately with - errno set to EWOULDBLOCK. In the former case, the call blocks until an - event becomes available. - The standard Linux poll() and/or select() system calls can be used with - the device file descriptor to watch for new events. For select(), the - file descriptor should be included in the exceptfds argument, and for - poll(), POLLPRI should be specified as the wake-up condition. - Only the latest event for each filter is saved. - - PARAMETERS - - int fd I File descriptor returned by a previous call to open(). - - int request I Equals DMX_SET_BUFFER_SIZE for this command. - - struct dmxEvent *ev O Pointer to the location where the event is to be stored. - - RETURNS - - EBADF fd is not a valid file descriptor. - - EFAULT ev points to an invalid address. - - EWOULDBLOCK There is no event pending, and the device is in non-blocking mode. - - - -

- - - - - - - - DVB CA API - - The DVB CA device controls the conditional access hardware. - This allows functionalities like display of menues and entering of PIN numbers. - It can be accessed through /dev/ost/ca. - - - The function calls defined in the include file audio.h are described in - detail below: - - - - CA API IO control calls - - The exact io calls for this device have not been decided on yet. - - - - - - - - - - - - - - - DVB Demux Kernel Module - - The demux device accesses the actual demux hardware through a - demux kernel module. This way other kernel modules (e.g. a generic DVB - network device) and not only the demux device can access the demux - hardware. - - - - DVB Demux Kernel Module API - - The demux kernel API gives access to the demuxer of the DVB - hardware to other kernel modules which implement devices like the Demux - device or generic DVB network devices. - - - The function calls defined in the include file demux.h are described in - detail below: - - - - Demux Directory API - - - The demux directory is a Linux kernel-wide facility for registering and - accessing the MPEG-2 TS demuxes in the system. Run-time registering and - unregistering of demux drivers is possible using this API. - - - All demux drivers in the directory implement the abstract interface dmx_demux_t. - - - -

-int dmx_register_demux ( dmx_demux_t* demux ) - - Description - - This function makes a demux driver interface available to the Linux kernel. - It is usually called by the init_module() function of the kernel module that - contains the demux driver. The caller of this function is responsible for - allocating dynamic or static memory for the demux structure and for initializing - its fields before calling this function. - The memory allocated for the demux structure must not be freed before calling - dmx_unregister_demux(), - - Returns - - 0 The command was successfully performed. - - -EEXIST A demux with the same value of the id field - already stored in the directory. - - -ENOSPC No space left in the directory. - - - -

- - -

- -int dmx_unregister_demux ( dmx_demux_t* demux ) - - Parameters - - dmx_demux_t* demux I/O Pointer to the demux API and instance variables. - - Description - - This function is called to indicate that the given demux interface is no longer - available. The caller of this function is responsible for freeing the memory of - the demux structure, if it was dynamically allocated before calling - dmx_register_demux(). - The cleanup_module() function of the kernel module that contains the demux - driver should call this function. Note that this function fails if the demux - is currently in use, i.e., release_demux() has not been called for the - interface. - - Returns - - 0 The command was successfully performed. - - -ENODEV No such demux registered. - - -EBUSY Demux is currently in use. - - - -

- - -

- -struct list_head* dmx_get_demuxes () - - Description - - Provides the caller with the list of registered demux interfaces, using the - standard list structure defined in the include file linux/list.h. - The include file demux.h defines the macro DMX_DIR_ENTRY() for converting an - element of the generic type struct list_head* to the type dmx_demux_t*. - The caller must not free the memory of any of the elements obtained via this - function call. - - Returns - - A list of demux interfaces, or NULL in the case of an empty list. - - - -

- - - - - - Demux API - - The demux API should be implemented for each demux in the system. It is used to - select the TS source of a demux and to manage the demux resources. When the - demux client allocates a resource via the demux API, it receives a pointer - to the API of that resource. - - - Each demux receives its TS input from a DVB front-end or from the memory, as - set via the demux API. In a system with more than one front-end, the API can - be used to select one of the DVB front-ends as a TS source for a demux, unless - this is fixed in the HW platform. The demux API only controls front-ends - regarding their connections with demuxes; the APIs used to set the other - front-end parameters, such as tuning, are not defined in this document. - - - The functions that implement the abstract interface demux_t should be defined - static or module private and registered to the Demux Directory for external - access. It is not necessary to implement every function in the demux_t struct, - however (for example, a demux interface might support Section filtering, but - not TS or PES filtering). The API client is expected to check the value of any - function pointer before calling the function: the value of NULL means "function - not available". - - - Whenever the functions of the demux API modify shared data, the possibilities - of lost update and race condition problems should be addressed, e.g. by - protecting parts of code with mutexes. This is especially important on - multi-processor hosts. - - - Note that functions called from a bottom half context must not sleep, at least - in the 2.2.x kernels. Even a simple memory allocation can result in a kernel - thread being put to sleep if swapping is needed. For example, the Linux kernel - calls the functions of a network device interface from a bottom half context. - Thus, if a demux API function is called from network device code, the function - must not sleep. - - -

- -int open ( demux_t* demux ) - - - Parameters - - demux_t* demux I Pointer to the demux API and instance data. - - Description - - This function reserves the demux for use by the caller and, if necessary, - initializes the demux. When the demux is no longer needed, the function close() - should be called. - It should be possible for multiple clients to access the demux at the same time. - Thus, the function implementation should increment the demux usage count when - open() is called and decrement it when close() is called. - - Returns - - 0 The command was successfully performed. - - -EUSERS Maximum usage count reached. - - -EINVAL Bad parameter. - - - -

- - -

- -int close ( demux_t* demux ) - - Parameters - - demux_t* demux I Pointer to the demux API and instance data. - - Description - - The function is called to indicate that the API client does not need to use - the demux anymore. As a result of this function, the demux usage count is - decremented by one. - When the usage count drops to zero, any demux resources can be released. - - Returns - - 0 The command was successfully performed. - - -ENODEV The demux was not in use. - - -EINVAL Bad parameter. - - - -

- - -

- -int write ( demux_t* demux, const char* buf, size_t count) - - Parameters - - demux_t* demux I/O Pointer to the demux API and instance data. - - const char* buf I Pointer to the TS data in kernel-space memory. - - size_t length I Length of the TS data. - - - - Description - - This function provides the demux driver with a memory buffer containing TS - packets. Instead of receiving TS packets from the DVB front-end, the demux - driver software will read packets from the memory. Any clients of this demux - with active TS, PES or Section filters will receive filtered data via the Demux - callback API (see 0). The function returns when all the data in the buffer has - been consumed by the demux. - Demux hardware typically cannot read TS from the memory. If this is the case, - memory-based filtering has to be implemented entirely in software. - - Returns - - 0 The command was successfully performed. - - -ENOSYS The command is not implemented. - - -EINVAL Bad parameter. - - - -

- - -

- -int allocate_ts_feed ( dmx_demux_t* demux, dmx_ts_feed_t** feed, dmx_ts_cb callback ) - - Parameters - - demux_t* demux I/O Pointer to the demux API and instance data. - - dmx_ts_feed_t** feed O Pointer to the TS feed API and instance data. - - dmx_ts_cb callback I Pointer to the callback function for - passing received TS packet - - Description - - Allocates a new TS feed, which is used to filter the TS packets carrying a - certain PID. - The TS feed normally corresponds to a hardware PID filter on the demux chip. - - Returns - - 0 The command was successfully performed. - - -EBUSY No more TS feeds available. - - -ENOSYS The command is not implemented. - - -EINVAL Bad parameters. - - - -

- - -

-int release_ts_feed ( dmx_demux_t* demux, dmx_ts_feed_t* feed) - - Parameters - - dmx_demux_t* demux I/O Pointer to the demux API and - instance data. - dmx_ts_feed_t* feed I Pointer to the TS feed API and - instance data. - - Function Detailed Description - Releases the resources allocated with allocate_ts_feed(). Any filtering in progress - on the TS feed should be stopped before calling this function. - - Function Returns - 0 The command was successfully performed. - -EINVAL Bad parameters. - -

- - -

-allocate_pes_feed() - - TBD - - - -

- - -

-release_pes_feed() - - TBD - - - -

- - -

-int allocate_section_feed ( dmx_demux_t* demux, - dmx_section_feed_t** - feed, - dmx_section_cb callback ) - - Function Parameters - demux_t* demux I/O Pointer to the demux API and - instance data. - dmx_section_feed_t** feed O Pointer to the section feed API and - - instance data. - dmx_section_cb callback I Pointer to the callback function for - passing received sections - - Function Detailed Description - Allocates a new section feed, i.e. a demux resource for filtering and receiving sections. - On platforms with hardware support for section filtering, a section feed is directly - mapped to the demux HW. On other platforms, TS packets are first PID filtered in - hardware and a hardware section filter then emulated in software. - The caller obtains an API pointer of type dmx_section_feed_t as an out parameter. - Using this API the caller can set filtering parameters and start receiving sections. - - Function Returns - 0 The command was successfully performed. - -EBUSY No more section feeds available. - -ENOSYS The command is not implemented. - -EINVAL Bad parameters. - -

- - -

- -int release_section_feed ( dmx_demux_t* demux, - dmx_section_feed_t* - feed - ) - Function Parameters - dmx_demux_t* demux I/O Pointer to the demux API and - instance data. - dmx_section_feed_t* feed I Pointer to the section feed API and - instance data. - - Function Detailed Description - Releases the resources allocated with allocate_section_feed(), including allocated - filters. Any filtering in progress on the section feed should be stopped before calling - this function. - - Function Returns - 0 The command was successfully performed. - -EINVAL Bad parameters. - - -

- - -

- -int descramble_mac_address ( dmx_demux_t* demux, - __u8* - buffer1, - size_t - buffer1_length, - __u8* buffer2, - size_t - buffer2_length, - __u16 pid ) - Function Parameters - dmx_demux_t* demux I/O Pointer to the demux API and - instance data. - __u8* buffer1 I Pointer to the first byte of the - section. - size_t buffer1_length I Length of the section data, - including headers and CRC, in - buffer1. - __u8* buffer2 I Pointer to the tail of the section - data, or NULL. The pointer has a - non-NULL value if the section wraps - past the end of a cyclic buffer. - size_t buffer2_length I Length of the section data, - including headers and CRC, in - buffer2 - __u16 pid I The PID on which the section was - received. Useful for obtaining the - descrambling key, e.g. from a DVB - Common Access facility. - - Function Detailed Description - This function runs a descrambling algorithm on the destination MAC address field of a - DVB Datagram Section, replacing the original address with its unencrypted version. - Otherwise, the description on the function descramble_section_payload() applies - also to this function. - - Function Returns - 0 The command was successfully performed. - -ENOSYS No descrambling facility available. - -EINVAL Bad parameters. - - - - -

- - -

- -int descramble_section_payload ( dmx_demux_t* demux, - __u8* - buffer1, - size_t - buffer1_length, - __u8* buffer2, - size_t - buffer2_length, - __u16 pid ) - Function Parameters - dmx_demux_t* demux I/O Pointer to the demux API and - instance data. - __u8* buffer1 I/O Pointer to the first byte of the - section. - size_t buffer1_length I Length of the section data, - including headers and CRC, in - buffer1. - __u8* buffer2 I Pointer to the tail of the section - data, or NULL. The pointer has a - non-NULL value if the section wraps - past the end of a cyclic buffer. - size_t buffer2_length I Length of the section data, - including headers and CRC, in - buffer2 - __u16 pid I The PID on which the section was - received. Useful for obtaining the - descrambling key, e.g. from a DVB - Common Access facility. - - Function Detailed Description - This function runs a descrambling algorithm on the payload of a DVB Datagram - Section, replacing the original payload with its unencrypted version. The function will - be called from the demux API implementation; the API client need not call this function - directly. - Section-level scrambling algorithms are currently standardized only for DVB-RCC - (return channel over 2-directional cable TV network) systems. For all other DVB - networks, encryption schemes are likely to be proprietary to each data broadcaster. - Thus, it is expected that this function pointer will have the value of NULL (i.e., function - not available) in most demux API implementations. Nevertheless, it should be possible - to use the function pointer as a hook for dynamically adding a "plug-in" descrambling - facility to a demux driver. - - - While this function is not needed with hardware-based section descrambling, the - descramble_section_payload function pointer can be used to override the default - hardware-based descrambling algorithm: if the function pointer has a non-NULL value, - the corresponding function should be used instead of any descrambling hardware. - - Function Returns - 0 The command was successfully performed. - -ENOSYS No descrambling facility available. - -EINVAL Bad parameters. - - -

- - -

- -int add_frontend ( dmx_demux_t* demux, - dmx_frontend_t* - frontend); - - Function Parameters - dmx_demux_t* demux I/O Pointer to the demux API and instance - data. - dmx_frontend_t* frontend I/O Pointer to the front-end instance data. - - Function Detailed Description - Registers a connectivity between a demux and a front-end, i.e., indicates that the - demux can be connected via a call to connect_frontend() to use the given front-end - as a TS source. The client of this function has to allocate dynamic or static memory for - the frontend structure and initialize its fields before calling this function. - This function is normally called during the driver initialization. The caller must not free - the memory of the frontend struct before successfully calling remove_frontend(). - - Function Returns - 0 The command was successfully performed. - -EEXIST A front-end with the same value of the id field - already registered. - -EINUSE The demux is in use. - -ENOMEM No more front-ends can be added. - -EINVAL Bad parameters. - -

- - -

- -int remove_frontend ( dmx_demux_t* demux, - dmx_frontend_t* frontend ) - Function Parameters - dmx_demux_t* demux I/O Pointer to the demux API and instance - data. - dmx_frontend_t* frontend I/O Pointer to the front-end instance data. - - Function Detailed Description - Indicates that the given front-end, registered by a call to add_frontend(), can no - longer be connected as a TS source by this demux. The function should be called - when a front-end driver or a demux driver is removed from the system. If the front-end - is in use, the function fails with the return value of -EBUSY. - After succesfully calling this function, the caller can free the memory of the frontend - struct if it was dynamically allocated before the add_frontend() operation. - - Function Returns - 0 The command was successfully performed. - -EINVAL Bad parameters. - -EBUSY The front-end is in use, i.e. a call to - connect_frontend() has not been followed by - a call to disconnect_frontend(). - - -

- - -

- -struct list_head* get_frontends ( dmx_demux_t* demux ) - Function Parameters - dmx_demux_t* demux I Pointer to the demux API and - instance data. - - Function Detailed Description - Provides the APIs of the front-ends that have been registered for this demux. Any of - the front-ends obtained with this call can be used as a parameter for - connect_frontend(). - - - The include file demux.h contains the macro DMX_FE_ENTRY() for converting an - element of the generic type struct list_head* to the type dmx_frontend_t*. - The caller must not free the memory of any of the elements obtained via this function - call. - - Function Returns - A list of front-end interfaces, or NULL in the case of an empty list. - -

- - -

- -int connect_frontend ( dmx_demux_t* demux, - dmx_frontend_t* frontend ) - Function Parameters - dmx_demux_t* demux I/O Pointer to the demux API and instance - data. - dmx_frontend_t* frontend I/O Pointer to the front-end instance data. - - Function Detailed Description - Connects the TS output of the front-end to the input of the demux. A demux can only - be connected to a front-end registered to the demux with the function - add_frontend(). - It may or may not be possible to connect multiple demuxes to the same front-end, - depending on the capabilities of the HW platform. When not used, the front-end should - be released by calling disconnect_frontend(). - - Function Returns - 0 The command was successfully performed. - -EINVAL Bad parameters. - -EBUSY The front-end is in use. - -

- - -

- -int disconnect_frontend ( dmx_demux_t* demux ) - - - Function Parameters - dmx_demux_t* demux I/O Pointer to the demux API and instance data. - - Function Detailed Description - Disconnects the demux and a front-end previously connected by a - connect_frontend() call. - - Function Returns - 0 The command was successfully performed. - -EINVAL Bad parameters. - - -

- - - - - Demux Callback API - - This kernel-space API comprises the callback functions that deliver filtered data to the - demux client. Unlike the other APIs, these API functions are provided by the client and - called from the demux code. - - - The function pointers of this abstract interface are not packed into a structure as in the - other demux APIs, because the callback functions are registered and used - independent of each other. As an example, it is possible for the API client to provide - several callback functions for receiving TS packets and no callbacks for PES packets - or sections. - - - The functions that implement the callback API need not be re-entrant: when a demux - driver calls one of these functions, the driver is not allowed to call the function again - before the original call returns. If a callback is triggered by a hardware interrupt, it is - recommended to use the Linux "bottom half" mechanism or start a tasklet instead of - making the callback function call directly from a hardware interrupt. - - - -

-int dmx_ts_cb ( __u8* buffer1, size_t buffer1_length, - __u8* buffer2, size_t buffer2_length, - dmx_ts_feed_t* source, dmx_success_t success ) - - Parameters - - __u8* buffer1 I Pointer to the start of the filtered TS packets. - - size_t buffer1_length I Length of the TS data in buffer1. - - __u8* buffer2 I Pointer to the tail of the filtered TS packets, or NULL. - - size_t buffer2_length I Length of the TS data in buffer2. - - dmx_ts_feed_t* source I Indicates which TS feed is the source of the callback. - - dmx_success_t success I Indicates if there was an error in TS reception. - - Description - - This function, provided by the client of the demux API, is called from the - demux code. The function is only called when filtering on this TS feed has - been enabled using the start_filtering() function. If conflict resolution - is used (see Error! Reference source not found.), no callbacks are made to - clients that have been put "on hold" regarding a TS Feed resource. - Any TS packets that match the filter settings are copied to a cyclic buffer. - The filtered TS packets are delivered to the client using this callback - function. The size of the cyclic buffer is controlled by the - circular_buffer_size parameter of the set() function in the TS Feed API. It is - expected that the buffer1 and buffer2 callback parameters point to addresses - within the circular buffer, but other implementations are also - possible. Note that the called party should not try to free the memory the - buffer1 and buffer2 parameters point to. - When this function is called, the buffer1 parameter typically points to the - start of the first undelivered TS packet within a cyclic buffer. The buffer2 - buffer parameter is normally NULL, except when the received TS packets have - crossed the last address of the cyclic buffer and "wrapped" to the beginning - of the buffer. In the latter case the buffer1 parameter would contain an - address within the cyclic buffer, while the buffer2 parameter would contain - the first address of the cyclic buffer. - The number of bytes delivered with this function (i.e. buffer1_length + - buffer2_length) is usually equal to the value of callback_length parameter given - in the set() function, with one exception: if a timeout occurs before receiving - callback_length bytes of TS data, any undelivered packets are immediately - delivered to the client by calling this function. The timeout duration is - controlled by the set() function in the TS Feed API. - If a TS packet is received with errors that could not be fixed by the TS-level - forward error correction (FEC), the Transport_error_indicator flag of the TS - packet header should be set. The TS packet should not be discarded, as the - error can possibly be corrected by a higher layer protocol. - If the called party is slow in processing the callback, it is possible that - the circular buffer eventually fills up. If this happens, the demux driver - should discard any TS packets received while the buffer is full. The error - should be indicated to the client on the next callback by setting the success - parameter to the value of DMX_OVERRUN_ERROR. - - The type of data returned to the callback can be selected by the - new function int (*set_type) (struct dmx_ts_feed_s* feed, int type, - dmx_ts_pes_t pes_type) which is part of the dmx_ts_feed_s struct - (also cf. to the include file ost/demux.h) - The type parameter decides if the raw TS packet (TS_PACKET) or just the - payload (TS_PACKET|TS_PAYLOAD_ONLY) should be returned. - If additionally the TS_DECODER bit is set the stream will also be sent - to the hardware MPEG decoder. In this case, the second flag decides - as what kind of data the stream should be interpreted. - The possible choices are one of DMX_TS_PES_AUDIO, DMX_TS_PES_VIDEO, - DMX_TS_PES_TELETEXT, DMX_TS_PES_SUBTITLE, DMX_TS_PES_PCR, or - DMX_TS_PES_OTHER. - - - Returns - - 0 Continue filtering. - - -1 Stop filtering - has the same effect as a call - to stop_filtering() on the TS Feed API. - - - -

- - -

- -dmx_pes_cb() - - TBD - -

- - -

- -int dmx_section_cb ( __u8* buffer1, - size_t - buffer1_length, - __u8* - buffer2, - size_t buffer2_length, - dmx_section_filter_t* - source, - dmx_success_t success ) - - Function Parameters - __u8* buffer1 I Pointer to the start of the filtered section, e.g. - within the cyclic buffer of the demux driver. - size_t buffer1_length I Length of the filtered section data in buffer1, - including headers and CRC. - __u8* buffer2 Pointer to the tail of the filtered section data, or - NULL. Useful to handle the wrapping of a cyclic - buffer. - size_t buffer2_length Length of the filtered section data in buffer2, - including headers and CRC. - dmx_section_filter_t* I Indicates the filter that triggered the callback. - filter - dmx_success_t success I Indicates if there was an error in section - reception. - - Function Detailed Description - This function, provided by the client of the demux API, is called from the demux code. - The function is only called when filtering of sections has been enabled using the - function start_filtering() of the section feed API. - When the demux driver has received a complete section that matches at least one - section filter, the client is notified via this callback function. Normally this function is - called for each received section; however, it is also possible to deliver multiple sections - with one callback, for example when the system load is high. - If an error occurs while receiving a section, this function should be called with the - corresponding error type set in the success field, whether or not there is data to - deliver. - The Section Feed implementation should maintain a cyclic buffer for received sections. - However, this is not necessary if the Section Feed API is implemented as a client of - - - the TS Feed API, because the TS Feed implementation then buffers the - received data. - The size of the circular buffer can be configured using the set() function in the - Section Feed API. If there is no room in the circular buffer when a new section is - received, the section must be discarded. If this happens, the value of the success - parameter should be DMX_OVERRUN_ERROR on the next callback. - - Function Returns - 0 Continue filtering. - -1 Stop filtering - has the same effect as a call - to stop_filtering() on the Section Feed - API. - -

- - - - - - TS Feed API - - A TS feed is typically mapped to a hardware PID filter on the demux chip. Using this - API, the client can set the filtering properties to start/stop filtering TS packets on a - particular TS feed. The API is defined as an abstract interface of the type - dmx_ts_feed_t. - - - The functions that implement the interface should be defined static or module - private. The client can get the handle of a TS feed API by calling the function - allocate_ts_feed() in the demux API. - - -

- -int set ( dmx_ts_feed_t* feed, - __u16 - pid, - size_t callback_length, - size_t - cyclic_buffer_size, - int - descramble, - struct timespec timeout) - - Parameters - - dmx_ts_feed_t* feed I/O Pointer to the TS feed API and - instance data. - __u16 pid I PID value to filter. Only the TS - packets carrying the specified PID will - be passed to the API client. - size_t callback_length I Number of bytes to deliver with each - call to the dmx_ts_cb() callback - function. The value of this - parameter should be a multiple of - 188. - - size_t cyclic_buffer_size I Size of the cyclic buffer for the filtered - TS packets. - int descramble I If non-zero, descramble the filtered - TS packets. - struct timespec timeout I Maximum time to wait before - delivering received TS packets to the - client. - - Function Detailed Description - This function sets the parameters of a TS feed. Any filtering in progress on the TS feed - must be stopped before calling this function. - - Function Returns - 0 The command was successfully performed. - -ENOMEM Not enough memory for the requested - buffer size. - -ENOSYS No descrambling facility available for TS - packets. - -EINVAL Bad parameters. - -

- - - -

- -int start_filtering ( dmx_ts_feed_t* feed ) - - Parameters - - dmx_ts_feed_t* feed I Pointer to the TS feed API and instance data. - - Function Detailed Description - Starts filtering TS packets on this TS feed, according to its settings. The PID value to - filter can be set by the API client. All matching TS packets are delivered - asynchronously to the client, using the callback function registered with - allocate_ts_feed(). - - Function Returns - 0 The command was successfully performed. - -EINVAL Bad parameters. - - -

- - -

- -int stop_filtering ( dmx_ts_feed_t* feed ) - - Parameters - - dmx_ts_feed_t* feed I/O Pointer to the TS feed API and instance data. - - Description - - Stops filtering TS packets on this TS feed. - - Returns - - 0 The command was successfully performed. - - -EINVAL Bad parameters. - - - -

- - - - - PES Feed API - - TBD - - - - - Section Feed API - - A section feed is a resource consisting of a PID filter and a set of section filters. Using - this API, the client can set the properties of a section feed and to start/stop filtering. - The API is defined as an abstract interface of the type dmx_section_feed_t. - The functions that implement the interface should be defined static or module - private. The client can get the handle of a section feed API by calling the function - allocate_section_feed() in the demux API. - - - On demux platforms that provide section filtering in hardware, the Section Feed API - implementation provides a software wrapper for the demux hardware. Other platforms - may support only PID filtering in hardware, requiring that TS packets are converted to - sections in software. In the latter case the Section Feed API implementation can be a - client of the TS Feed API. - - - -

- -int set ( dmx_section_feed_t* feed, __u16 pid, size_t circular_buffer_size, - int descramble, int check_crc ) - - Parameters - - dmx_section_feed_t* feed I/O Pointer to the section feed API and - instance data. - __u16 pid I PID value to filter; only the TS packets - carrying the specified PID will be - accepted. - size_t circular_buffer_size I Size of the cyclic buffer for filtered - sections. - int descramble I If non-zero, descramble any sections - that are scrambled. - int check_crc I If non-zero, check the CRC values of - filtered sections. - - Function Detailed Description - This function sets the parameters of a section feed. Any filtering in progress on the - section feed must be stopped before calling this function. - If descrambling is enabled, the payload_scrambling_control and - address_scrambling_control fields of received DVB datagram sections should be - observed. If either one is non-zero, the section should be descrambled either in - hardware or using the functions descramble_mac_address() and - descramble_section_payload() of the demux API. Note that according to the - MPEG-2 Systems specification [3], only the payloads of private sections can be - scrambled while the rest of the section data must be sent in the clear. - - Function Returns - 0 The command was successfully performed. - -ENOMEM Not enough memory available for the requested - buffer size. - -ENOSYS No descrambling facility available for sections. - -EINVAL Bad parameters. - -

- - -

- -int allocate_filter(dmx_section_feed_t* feed, dmx_section_filter_t** filter) - - Parameters - dmx_section_feed_t* feed I/O Pointer to the section feed API and - instance data. - dmx_section_filter_t** filter O Pointer to the allocated filter. - - - Function Detailed Description - This function is used to allocate a section filter on the demux. It should only be called - when no filtering is in progress on this section feed. If a filter cannot be allocated, the - function fails with -ENOSPC. See below for the format of the section filter struct provided - as an out parameter: - typedef struct { - __u8 filter_value [DMX_MAX_FILTER_SIZE]; - __u8 filter_mask [DMX_MAX_FILTER_SIZE]; - struct dmx_section_feed_s* parent; /* Back-pointer */ - void* priv; /* Private data of the client */ - } dmx_section_filter_t; - - The bitfields filter_mask and filter_value should only be modified when no - filtering is in progress on this section feed. filter_mask controls which bits of - filter_value are compared with the section headers/payload. On a binary value of 1 - in filter_mask, the corresponding bits are compared. The filter only accepts sections - that are equal to filter_value in all the tested bit positions. Any changes to the - values of filter_mask and filter_value are guaranteed to take effect only when - the start_filtering() function is called next time. The parent pointer in the struct - is initialized by the API implementation to the value of the feed parameter. The priv - pointer is not used by the API implementation, and can thus be freely utilized by the - caller of this function. Any data pointed to by the priv pointer is available to the - recipient of the dmx_section_cb() function call. - While the maximum section filter length (DMX_MAX_FILTER_SIZE) is currently set at 16 - bytes, hardware filters of that size are not available on all platforms. Therefore, section - filtering will often take place first in hardware, followed by filtering in software for the - header bytes that were not covered by a hardware filter. The filter_mask field can be - checked to determine how many bytes of the section filter are actually used, and if the - hardware filter will suffice. Additionally, software-only section filters can optionally be - allocated to clients when all hardware section filters are in use. - Note that on most demux hardware it is not possible to filter on the section_length field - of the section header - thus this field is ignored, even though it is included in - filter_value and filter_mask fields. - - Function Returns - 0 The command was successfully performed. - -ENOSPC No filters of given type and length available. - -EINVAL Bad parameters. - -

- - -

-int release_filter ( dmx_section_feed_t* feed, dmx_section_filter_t* filter) - - Parameters - dmx_section_feed_t* feed I/O Pointer to the section feed API and instance - data. - dmx_section_filter_t* I/O Pointer to the instance data of a section filter. - filter - - Function Detailed Description - This function releases all the resources of a previously allocated section filter. The - function should not be called while filtering is in progress on this section feed. After - calling this function, the caller should not try to dereference the filter pointer. - - Function Returns - 0 The command was successfully performed. - -ENODEV No such filter allocated. - -EINVAL Bad parameters. - -

- - -

-int start_filtering ( dmx_section_feed_t* feed ) - - Parameters - dmx_section_feed_t* feed I/O Pointer to the section feed API and - instance data. - - Function Detailed Description - Starts filtering sections on this section feed, according to its settings. Sections are first - filtered based on their PID and then matched with the section filters allocated for this - feed. If the section matches the PID filter and at least one section filter, it is delivered - to the API client. The section is delivered asynchronously using the callback function - registered with allocate_section_feed(). - - Function Returns - 0 The command was successfully performed. - -EINVAL Bad parameters. - -

- - -

-int stop_filtering ( dmx_section_feed_t* feed ) - - Parameters - - dmx_section_feed_t* feed I/O Pointer to the section feed API and instance data. - - Description - - Stops filtering sections on this section feed. Note that any changes to the - filtering parameters (filter_value, filter_mask, etc.) should only be made - when filtering is stopped. - - Returns - - 0 The command was successfully performed. - - -EINVAL Bad parameters. - - - -

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Linux DVB API

DVB Audio API

DVB Demux API

DVB Demux Kernel API

DVB Frontend API

DVB SEC API

DVB Video API