--- zzzz-none-000/linux-3.10.107/Documentation/DocBook/media/dvb/frontend.xml 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/Documentation/DocBook/media/dvb/frontend.xml 2021-02-04 17:41:59.000000000 +0000 @@ -1,485 +1,112 @@ DVB Frontend API -The DVB frontend device controls the tuner and DVB demodulator -hardware. It can be accessed through /dev/dvb/adapter0/frontend0. Data types and and -ioctl definitions can be accessed by including linux/dvb/frontend.h in your application. - -DVB frontends come in three varieties: DVB-S (satellite), DVB-C -(cable) and DVB-T (terrestrial). Transmission via the internet (DVB-IP) -is not yet handled by this API but a future extension is possible. For -DVB-S the frontend device also supports satellite equipment control -(SEC) via DiSEqC and V-SEC protocols. The DiSEqC (digital SEC) -specification is available from +The DVB frontend API was designed to support three types of delivery systems: + + Terrestrial systems: DVB-T, DVB-T2, ATSC, ATSC M/H, ISDB-T, DVB-H, DTMB, CMMB + Cable systems: DVB-C Annex A/C, ClearQAM (DVB-C Annex B), ISDB-C + Satellite systems: DVB-S, DVB-S2, DVB Turbo, ISDB-S, DSS + +The DVB frontend controls several sub-devices including: + + Tuner + Digital TV demodulator + Low noise amplifier (LNA) + Satellite Equipment Control (SEC) hardware (only for Satellite). + +The frontend can be accessed through + /dev/dvb/adapter?/frontend?. Data types and + ioctl definitions can be accessed by including + linux/dvb/frontend.h in your application. + + +NOTE: Transmission via the internet (DVB-IP) + is not yet handled by this API but a future extension is possible. +On Satellite systems, the API support for the Satellite Equipment Control + (SEC) allows to power control and to send/receive signals to control the + antenna subsystem, selecting the polarization and choosing the Intermediate + Frequency IF) of the Low Noise Block Converter Feed Horn (LNBf). It + supports the DiSEqC and V-SEC protocols. The DiSEqC (digital SEC) +specification is available at Eutelsat. -Note that the DVB API may also be used for MPEG decoder-only PCI -cards, in which case there exists no frontend device. +
+Querying frontend information -
-Frontend Data Types - -
-Frontend type - -For historical reasons, frontend types are named by the type of modulation used in -transmission. The fontend types are given by fe_type_t type, defined as: - - -Frontend types - - &cs-def; - - - fe_type - Description - DTV_DELIVERY_SYSTEM equivalent type - - - - - FE_QPSK - For DVB-S standard - SYS_DVBS - - - FE_QAM - For DVB-C annex A standard - SYS_DVBC_ANNEX_A - - - FE_OFDM - For DVB-T standard - SYS_DVBT - - - FE_ATSC - For ATSC standard (terrestrial) or for DVB-C Annex B (cable) used in US. - SYS_ATSC (terrestrial) or SYS_DVBC_ANNEX_B (cable) - -
- -Newer formats like DVB-S2, ISDB-T, ISDB-S and DVB-T2 are not described at the above, as they're -supported via the new FE_GET_PROPERTY/FE_GET_SET_PROPERTY ioctl's, using the DTV_DELIVERY_SYSTEM parameter. - - -The usage of this field is deprecated, as it doesn't report all supported standards, and -will provide an incomplete information for frontends that support multiple delivery systems. -Please use DTV_ENUM_DELSYS instead. -
- -
-frontend capabilities - -Capabilities describe what a frontend can do. Some capabilities can only be supported for -a specific frontend type. - - typedef enum fe_caps { - FE_IS_STUPID = 0, - FE_CAN_INVERSION_AUTO = 0x1, - FE_CAN_FEC_1_2 = 0x2, - FE_CAN_FEC_2_3 = 0x4, - FE_CAN_FEC_3_4 = 0x8, - FE_CAN_FEC_4_5 = 0x10, - FE_CAN_FEC_5_6 = 0x20, - FE_CAN_FEC_6_7 = 0x40, - FE_CAN_FEC_7_8 = 0x80, - FE_CAN_FEC_8_9 = 0x100, - FE_CAN_FEC_AUTO = 0x200, - FE_CAN_QPSK = 0x400, - FE_CAN_QAM_16 = 0x800, - FE_CAN_QAM_32 = 0x1000, - FE_CAN_QAM_64 = 0x2000, - FE_CAN_QAM_128 = 0x4000, - FE_CAN_QAM_256 = 0x8000, - FE_CAN_QAM_AUTO = 0x10000, - FE_CAN_TRANSMISSION_MODE_AUTO = 0x20000, - FE_CAN_BANDWIDTH_AUTO = 0x40000, - FE_CAN_GUARD_INTERVAL_AUTO = 0x80000, - FE_CAN_HIERARCHY_AUTO = 0x100000, - FE_CAN_8VSB = 0x200000, - FE_CAN_16VSB = 0x400000, - FE_HAS_EXTENDED_CAPS = 0x800000, - FE_CAN_MULTISTREAM = 0x4000000, - FE_CAN_TURBO_FEC = 0x8000000, - FE_CAN_2G_MODULATION = 0x10000000, - FE_NEEDS_BENDING = 0x20000000, - FE_CAN_RECOVER = 0x40000000, - FE_CAN_MUTE_TS = 0x80000000 - } fe_caps_t; - -
- -
-frontend information - -Information about the frontend ca be queried with - FE_GET_INFO. - - - struct dvb_frontend_info { - char name[128]; - fe_type_t type; - uint32_t frequency_min; - uint32_t frequency_max; - uint32_t frequency_stepsize; - uint32_t frequency_tolerance; - uint32_t symbol_rate_min; - uint32_t symbol_rate_max; - uint32_t symbol_rate_tolerance; /⋆ ppm ⋆/ - uint32_t notifier_delay; /⋆ ms ⋆/ - fe_caps_t caps; - }; - -
- -
-diseqc master command - -A message sent from the frontend to DiSEqC capable equipment. - - struct dvb_diseqc_master_cmd { - uint8_t msg [6]; /⋆ { framing, address, command, data[3] } ⋆/ - uint8_t msg_len; /⋆ valid values are 3...6 ⋆/ - }; - -
-
-diseqc slave reply - -A reply to the frontend from DiSEqC 2.0 capable equipment. - - struct dvb_diseqc_slave_reply { - uint8_t msg [4]; /⋆ { framing, data [3] } ⋆/ - uint8_t msg_len; /⋆ valid values are 0...4, 0 means no msg ⋆/ - int timeout; /⋆ return from ioctl after timeout ms with ⋆/ - }; /⋆ errorcode when no message was received ⋆/ - -
- -
-diseqc slave reply -The voltage is usually used with non-DiSEqC capable LNBs to switch the polarzation -(horizontal/vertical). When using DiSEqC epuipment this voltage has to be switched -consistently to the DiSEqC commands as described in the DiSEqC spec. - - typedef enum fe_sec_voltage { - SEC_VOLTAGE_13, - SEC_VOLTAGE_18 - } fe_sec_voltage_t; - -
- -
-SEC continuous tone - -The continuous 22KHz tone is usually used with non-DiSEqC capable LNBs to switch the -high/low band of a dual-band LNB. When using DiSEqC epuipment this voltage has to -be switched consistently to the DiSEqC commands as described in the DiSEqC -spec. - - typedef enum fe_sec_tone_mode { - SEC_TONE_ON, - SEC_TONE_OFF - } fe_sec_tone_mode_t; - -
- -
-SEC tone burst - -The 22KHz tone burst is usually used with non-DiSEqC capable switches to select -between two connected LNBs/satellites. When using DiSEqC epuipment this voltage has to -be switched consistently to the DiSEqC commands as described in the DiSEqC -spec. - - typedef enum fe_sec_mini_cmd { - SEC_MINI_A, - SEC_MINI_B - } fe_sec_mini_cmd_t; - - - -
- -
-frontend status -Several functions of the frontend device use the fe_status data type defined -by - -typedef enum fe_status { - FE_HAS_SIGNAL = 0x01, - FE_HAS_CARRIER = 0x02, - FE_HAS_VITERBI = 0x04, - FE_HAS_SYNC = 0x08, - FE_HAS_LOCK = 0x10, - FE_TIMEDOUT = 0x20, - FE_REINIT = 0x40, -} fe_status_t; - -to indicate the current state and/or state changes of the frontend hardware: - - - - -FE_HAS_SIGNAL -The frontend has found something above the noise level - -FE_HAS_CARRIER -The frontend has found a DVB signal - -FE_HAS_VITERBI -The frontend FEC inner coding (Viterbi, LDPC or other inner code) is stable - -FE_HAS_SYNC -Syncronization bytes was found - -FE_HAS_LOCK -The DVB were locked and everything is working - -FE_TIMEDOUT -no lock within the last about 2 seconds - -FE_REINIT -The frontend was reinitialized, application is -recommended to reset DiSEqC, tone and parameters - - - -
- -
-frontend parameters -The kind of parameters passed to the frontend device for tuning depend on -the kind of hardware you are using. -The struct dvb_frontend_parameters uses an -union with specific per-system parameters. However, as newer delivery systems -required more data, the structure size weren't enough to fit, and just -extending its size would break the existing applications. So, those parameters -were replaced by the usage of -FE_GET_PROPERTY/FE_SET_PROPERTY ioctl's. The -new API is flexible enough to add new parameters to existing delivery systems, -and to add newer delivery systems. -So, newer applications should use -FE_GET_PROPERTY/FE_SET_PROPERTY instead, in -order to be able to support the newer System Delivery like DVB-S2, DVB-T2, -DVB-C2, ISDB, etc. -All kinds of parameters are combined as an union in the FrontendParameters structure: - -struct dvb_frontend_parameters { - uint32_t frequency; /⋆ (absolute) frequency in Hz for QAM/OFDM ⋆/ - /⋆ intermediate frequency in kHz for QPSK ⋆/ - fe_spectral_inversion_t inversion; - union { - struct dvb_qpsk_parameters qpsk; - struct dvb_qam_parameters qam; - struct dvb_ofdm_parameters ofdm; - struct dvb_vsb_parameters vsb; - } u; -}; - -In the case of QPSK frontends the frequency field specifies the intermediate -frequency, i.e. the offset which is effectively added to the local oscillator frequency (LOF) of -the LNB. The intermediate frequency has to be specified in units of kHz. For QAM and -OFDM frontends the frequency specifies the absolute frequency and is given in Hz. - - -
-QPSK parameters -For satellite QPSK frontends you have to use the dvb_qpsk_parameters structure: - - struct dvb_qpsk_parameters { - uint32_t symbol_rate; /⋆ symbol rate in Symbols per second ⋆/ - fe_code_rate_t fec_inner; /⋆ forward error correction (see above) ⋆/ - }; - -
-
-QAM parameters -for cable QAM frontend you use the dvb_qam_parameters structure: - - struct dvb_qam_parameters { - uint32_t symbol_rate; /⋆ symbol rate in Symbols per second ⋆/ - fe_code_rate_t fec_inner; /⋆ forward error correction (see above) ⋆/ - fe_modulation_t modulation; /⋆ modulation type (see above) ⋆/ - }; - -
-
-VSB parameters -ATSC frontends are supported by the dvb_vsb_parameters structure: - -struct dvb_vsb_parameters { - fe_modulation_t modulation; /⋆ modulation type (see above) ⋆/ -}; - -
-
-OFDM parameters -DVB-T frontends are supported by the dvb_ofdm_parameters structure: - - struct dvb_ofdm_parameters { - fe_bandwidth_t bandwidth; - fe_code_rate_t code_rate_HP; /⋆ high priority stream code rate ⋆/ - fe_code_rate_t code_rate_LP; /⋆ low priority stream code rate ⋆/ - fe_modulation_t constellation; /⋆ modulation type (see above) ⋆/ - fe_transmit_mode_t transmission_mode; - fe_guard_interval_t guard_interval; - fe_hierarchy_t hierarchy_information; - }; - -
-
-frontend spectral inversion -The Inversion field can take one of these values: - - -typedef enum fe_spectral_inversion { - INVERSION_OFF, - INVERSION_ON, - INVERSION_AUTO -} fe_spectral_inversion_t; - -It indicates if spectral inversion should be presumed or not. In the automatic setting -(INVERSION_AUTO) the hardware will try to figure out the correct setting by -itself. - -
-
-frontend code rate -The possible values for the fec_inner field used on -struct dvb_qpsk_parameters and -struct dvb_qam_parameters are: - - -typedef enum fe_code_rate { - FEC_NONE = 0, - FEC_1_2, - FEC_2_3, - FEC_3_4, - FEC_4_5, - FEC_5_6, - FEC_6_7, - FEC_7_8, - FEC_8_9, - FEC_AUTO, - FEC_3_5, - FEC_9_10, -} fe_code_rate_t; - -which correspond to error correction rates of 1/2, 2/3, etc., no error correction or auto -detection. - -
-
-frontend modulation type for QAM, OFDM and VSB -For cable and terrestrial frontends, e. g. for -struct dvb_qpsk_parameters, -struct dvb_qam_parameters and -struct dvb_qam_parameters, -it needs to specify the quadrature modulation mode which can be one of the following: - - - typedef enum fe_modulation { - QPSK, - QAM_16, - QAM_32, - QAM_64, - QAM_128, - QAM_256, - QAM_AUTO, - VSB_8, - VSB_16, - PSK_8, - APSK_16, - APSK_32, - DQPSK, - } fe_modulation_t; - -
-
-More OFDM parameters -
-Number of carriers per channel - -typedef enum fe_transmit_mode { - TRANSMISSION_MODE_2K, - TRANSMISSION_MODE_8K, - TRANSMISSION_MODE_AUTO, - TRANSMISSION_MODE_4K, - TRANSMISSION_MODE_1K, - TRANSMISSION_MODE_16K, - TRANSMISSION_MODE_32K, - } fe_transmit_mode_t; - -
-
-frontend bandwidth - -typedef enum fe_bandwidth { - BANDWIDTH_8_MHZ, - BANDWIDTH_7_MHZ, - BANDWIDTH_6_MHZ, - BANDWIDTH_AUTO, - BANDWIDTH_5_MHZ, - BANDWIDTH_10_MHZ, - BANDWIDTH_1_712_MHZ, -} fe_bandwidth_t; - -
-
-frontend guard inverval - -typedef enum fe_guard_interval { - GUARD_INTERVAL_1_32, - GUARD_INTERVAL_1_16, - GUARD_INTERVAL_1_8, - GUARD_INTERVAL_1_4, - GUARD_INTERVAL_AUTO, - GUARD_INTERVAL_1_128, - GUARD_INTERVAL_19_128, - GUARD_INTERVAL_19_256, -} fe_guard_interval_t; - -
-
-frontend hierarchy - -typedef enum fe_hierarchy { - HIERARCHY_NONE, - HIERARCHY_1, - HIERARCHY_2, - HIERARCHY_4, - HIERARCHY_AUTO - } fe_hierarchy_t; - -
-
- -
- -
-frontend events - - struct dvb_frontend_event { - fe_status_t status; - struct dvb_frontend_parameters parameters; - }; - -
+Usually, the first thing to do when the frontend is opened is to + check the frontend capabilities. This is done using FE_GET_INFO. This ioctl will enumerate + the DVB API version and other characteristics about the frontend, and + can be opened either in read only or read/write mode. +
+ +
+Querying frontend status and statistics + +Once FE_SET_PROPERTY + is called, the frontend will run a kernel thread that will periodically + check for the tuner lock status and provide statistics about the quality + of the signal. +The information about the frontend tuner locking status can be queried + using FE_READ_STATUS. +Signal statistics are provided via FE_GET_PROPERTY. + Please note that several statistics require the demodulator to be fully + locked (e. g. with FE_HAS_LOCK bit set). See + Frontend statistics indicators + for more details.
+&sub-dvbproperty;
Frontend Function Calls -
-open() -DESCRIPTION - - -This system call opens a named frontend device (/dev/dvb/adapter0/frontend0) + + + DVB frontend open() + &manvol; + + + + fe-open + Open a frontend device + + + + + #include <fcntl.h> + + int open + const char *device_name + int flags + + + + + + Arguments + + + + device_name + + Device to be opened. + + + + flags + + Open flags. Access can either be + O_RDWR or O_RDONLY. + Multiple opens are allowed with O_RDONLY. In this mode, only query and read ioctls are allowed. + Only one open is allowed in O_RDWR. In this mode, all ioctls are allowed. + When the O_NONBLOCK flag is given, the system calls may return &EAGAIN; when no data is available or when the device driver is temporarily busy. + Other flags have no effect. + + + + + + Description + This system call opens a named frontend device (/dev/dvb/adapter?/frontend?) for subsequent use. Usually the first thing to do after a successful open is to find out the frontend type with FE_GET_INFO. The device can be opened in read-only mode, which only allows monitoring of @@ -497,1052 +124,146 @@ 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. - - + -SYNOPSIS - -int open(const char ⋆deviceName, int flags); - - -PARAMETERS - - -const char - *deviceName - -Name of specific video 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) - - -RETURN VALUE - -ENODEV - -Device driver not loaded/available. - - -EINTERNAL - -Internal error. - - -EBUSY - -Device or resource busy. - - -EINVAL - -Invalid argument. - - -
+ + Return Value -
-close() -DESCRIPTION - - + On success open returns the new file +descriptor. On error -1 is returned, and the errno +variable is set appropriately. Possible error codes are: + + + + EACCES + + The caller has no permission to access the +device. + + + + EBUSY + + The the device driver is already in use. + + + + ENXIO + + No device corresponding to this device special file +exists. + + + + ENOMEM + + Not enough kernel memory was available to complete the +request. + + + + EMFILE + + The process already has the maximum number of +files open. + + + + ENFILE + + The limit on the total number of files open on the +system has been reached. + + + + ENODEV + + The device got removed. + + + + + + + + + DVB frontend close() + &manvol; + + + + fe-close + Close a frontend device + + + + + #include <unistd.h> + + int close + int fd + + + + + + Arguments + + + + fd + + &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. - - -SYNOPSIS - - -int close(int fd); - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -RETURN VALUE - -EBADF - -fd is not a valid open file descriptor. - - -
+
+ + Return Value + + The function returns 0 on +success, -1 on failure and the +errno is set appropriately. Possible error +codes: + + + + EBADF + + fd is not a valid open file +descriptor. + + + + + + +&sub-fe-get-info; +&sub-fe-read-status; +&sub-fe-get-property; +&sub-fe-diseqc-reset-overload; +&sub-fe-diseqc-send-master-cmd; +&sub-fe-diseqc-recv-slave-reply; +&sub-fe-diseqc-send-burst; +&sub-fe-set-tone; +&sub-fe-set-voltage; +&sub-fe-enable-high-lnb-voltage; +&sub-fe-set-frontend-tune-mode; -
-FE_READ_STATUS -DESCRIPTION - - -This ioctl call returns status information about the front-end. This call only - requires read-only access to the device. - - -SYNOPSIS - - -int ioctl(int fd, int request = FE_READ_STATUS, - fe_status_t ⋆status); - - -PARAMETERS - - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_READ_STATUS for this command. - - -struct fe_status_t - *status - -Points to the location where the front-end status word is - to be stored. - - -RETURN VALUE - -EBADF - -fd is not a valid open file descriptor. - - -EFAULT - -status points to invalid address. - -
-
-FE_READ_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. - - -SYNOPSIS - - -int ioctl(int fd, int request = FE_READ_BER, - uint32_t ⋆ber); - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_READ_BER for this command. - - -uint32_t *ber - -The bit error rate is stored into *ber. - - - -&return-value-dvb; -
- -
-FE_READ_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. - - -SYNOPSIS - - -int ioctl(int fd, int request = FE_READ_SNR, int16_t - ⋆snr); - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_READ_SNR for this command. - - -int16_t *snr - -The signal-to-noise ratio is stored into *snr. - - - -&return-value-dvb; -
- -
-FE_READ_SIGNAL_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. - - -SYNOPSIS - - -int ioctl( int fd, int request = - FE_READ_SIGNAL_STRENGTH, int16_t ⋆strength); - - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_READ_SIGNAL_STRENGTH for this - command. - - -int16_t *strength - -The signal strength value is stored into *strength. - - - -&return-value-dvb; -
- -
-FE_READ_UNCORRECTED_BLOCKS -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 calculated. For this command, - read-only access to the device is sufficient. - - -Note that the counter will wrap to zero after its maximum count has been - reached. - - -SYNOPSIS - - -int ioctl( int fd, int request = - FE_READ_UNCORRECTED_BLOCKS, uint32_t ⋆ublocks); - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_READ_UNCORRECTED_BLOCKS for this - command. - - -uint32_t *ublocks - -The total number of uncorrected blocks seen by the driver - so far. - - +
+DVB Frontend legacy API (a. k. a. DVBv3) +The usage of this API is deprecated, as it doesn't support all digital + TV standards, doesn't provide good statistics measurements and provides + incomplete information. This is kept only to support legacy applications. -&return-value-dvb; +&sub-frontend_legacy_api;
- -
-FE_SET_FRONTEND -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 FE_GET_EVENT and - FrontendEvent.) If a new FE_SET_FRONTEND 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. - - - -SYNOPSIS - - -int ioctl(int fd, int request = FE_SET_FRONTEND, - struct dvb_frontend_parameters ⋆p); - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_SET_FRONTEND for this command. - - -struct - dvb_frontend_parameters - *p - -Points to parameters for tuning operation. - - - -&return-value-dvb; - -EINVAL - -Maximum supported symbol rate reached. - - -
- -
-FE_GET_FRONTEND -DESCRIPTION - - -This ioctl call queries the currently effective frontend parameters. For this - command, read-only access to the device is sufficient. - - - -SYNOPSIS - - -int ioctl(int fd, int request = FE_GET_FRONTEND, - struct dvb_frontend_parameters ⋆p); - - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_SET_FRONTEND for this command. - - -struct - dvb_frontend_parameters - *p - -Points to parameters for tuning operation. - - - -&return-value-dvb; - -EINVAL - -Maximum supported symbol rate reached. - - - -
- -
-FE_GET_EVENT -DESCRIPTION - - -This ioctl call returns a frontend 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. 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 (EOVERFLOW) occurs the next time the queue is read. After - reporting the error condition in this fashion, subsequent - FE_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. - - - -SYNOPSIS - - -int ioctl(int fd, int request = QPSK_GET_EVENT, - struct dvb_frontend_event ⋆ev); - - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_GET_EVENT for this command. - - -struct - dvb_frontend_event - *ev - -Points to the location where the event, - - - -if any, is to be stored. - - - -&return-value-dvb; - -EWOULDBLOCK - -There is no event pending, and the device is in - non-blocking mode. - - -EOVERFLOW - -Overflow in event queue - one or more events were lost. - - -
- -
-FE_GET_INFO -DESCRIPTION - - -This ioctl call returns information about the front-end. This call only requires - read-only access to the device. - - -SYNOPSIS - - - - int ioctl(int fd, int request = FE_GET_INFO, struct - dvb_frontend_info ⋆info); - - -PARAMETERS - - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_GET_INFO for this command. - - -struct - dvb_frontend_info - *info - -Points to the location where the front-end information is - to be stored. - - -&return-value-dvb; -
- -
-FE_DISEQC_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. Not all - DVB adapters support this ioctl. - - - -SYNOPSIS - - -int ioctl(int fd, int request = - FE_DISEQC_RESET_OVERLOAD); - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_DISEQC_RESET_OVERLOAD for this - command. - - - -&return-value-dvb; -
- -
-FE_DISEQC_SEND_MASTER_CMD -DESCRIPTION - - -This ioctl call is used to send a a DiSEqC command. - - -SYNOPSIS - - -int ioctl(int fd, int request = - FE_DISEQC_SEND_MASTER_CMD, struct - dvb_diseqc_master_cmd ⋆cmd); - - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_DISEQC_SEND_MASTER_CMD for this - command. - - -struct - dvb_diseqc_master_cmd - *cmd - -Pointer to the command to be transmitted. - - - -&return-value-dvb; -
- -
-FE_DISEQC_RECV_SLAVE_REPLY -DESCRIPTION - - -This ioctl call is used to receive reply to a DiSEqC 2.0 command. - - - -SYNOPSIS - - -int ioctl(int fd, int request = - FE_DISEQC_RECV_SLAVE_REPLY, struct - dvb_diseqc_slave_reply ⋆reply); - - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_DISEQC_RECV_SLAVE_REPLY for this - command. - - -struct - dvb_diseqc_slave_reply - *reply - -Pointer to the command to be received. - - -&return-value-dvb; -
- -
-FE_DISEQC_SEND_BURST -DESCRIPTION - - -This ioctl call is used to send a 22KHz tone burst. - - - -SYNOPSIS - - -int ioctl(int fd, int request = - FE_DISEQC_SEND_BURST, fe_sec_mini_cmd_t burst); - - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_DISEQC_SEND_BURST for this command. - - -fe_sec_mini_cmd_t - burst - -burst A or B. - - - -&return-value-dvb; -
- -
-FE_SET_TONE -DESCRIPTION - - -This call is used to set the generation of the continuous 22kHz tone. This call - requires read/write permissions. - - -SYNOPSIS - - -int ioctl(int fd, int request = FE_SET_TONE, - fe_sec_tone_mode_t tone); - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_SET_TONE for this command. - - -fe_sec_tone_mode_t - tone - -The requested tone generation mode (on/off). - - -&return-value-dvb; -
- -
-FE_SET_VOLTAGE -DESCRIPTION - - -This call is used to set the bus voltage. This call requires read/write - permissions. - - -SYNOPSIS - - -int ioctl(int fd, int request = FE_SET_VOLTAGE, - fe_sec_voltage_t voltage); - - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_SET_VOLTAGE for this command. - - -fe_sec_voltage_t - voltage - -The requested bus voltage. - - - -&return-value-dvb; -
- -
-FE_ENABLE_HIGH_LNB_VOLTAGE -DESCRIPTION - - -If high != 0 enables slightly higher voltages instead of 13/18V (to compensate - for long cables). This call requires read/write permissions. Not all DVB - adapters support this ioctl. - - - -SYNOPSIS - - -int ioctl(int fd, int request = - FE_ENABLE_HIGH_LNB_VOLTAGE, int high); - - - -PARAMETERS - - -int fd - -File descriptor returned by a previous call to open(). - - -int request - -Equals FE_SET_VOLTAGE for this command. - - -int high - -The requested bus voltage. - - - -&return-value-dvb; -
- -
-FE_SET_FRONTEND_TUNE_MODE -DESCRIPTION - - -Allow setting tuner mode flags to the frontend. - - - -SYNOPSIS - - -int ioctl(int fd, int request = -FE_SET_FRONTEND_TUNE_MODE, unsigned int flags); - - - -PARAMETERS - - - unsigned int flags - - - -FE_TUNE_MODE_ONESHOT When set, this flag will disable any zigzagging or other "normal" tuning behaviour. Additionally, there will be no automatic monitoring of the lock status, and hence no frontend events will be generated. If a frontend device is closed, this flag will be automatically turned off when the device is reopened read-write. - - - - -&return-value-dvb; -
- -
- FE_DISHNETWORK_SEND_LEGACY_CMD -DESCRIPTION - - -WARNING: This is a very obscure legacy command, used only at stv0299 driver. Should not be used on newer drivers. -It provides a non-standard method for selecting Diseqc voltage on the frontend, for Dish Network legacy switches. -As support for this ioctl were added in 2004, this means that such dishes were already legacy in 2004. - - - -SYNOPSIS - - -int ioctl(int fd, int request = - FE_DISHNETWORK_SEND_LEGACY_CMD, unsigned long cmd); - - - -PARAMETERS - - - unsigned long cmd - - - -sends the specified raw cmd to the dish via DISEqC. - - - - -&return-value-dvb; -
- -
- -&sub-dvbproperty;