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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /Documentation/sound/cards/hdspm.rst | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'Documentation/sound/cards/hdspm.rst')
-rw-r--r-- | Documentation/sound/cards/hdspm.rst | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/Documentation/sound/cards/hdspm.rst b/Documentation/sound/cards/hdspm.rst new file mode 100644 index 000000000..5373e51ed --- /dev/null +++ b/Documentation/sound/cards/hdspm.rst @@ -0,0 +1,379 @@ +======================================= +Software Interface ALSA-DSP MADI Driver +======================================= + +(translated from German, so no good English ;-), + +2004 - winfried ritsch + + +Full functionality has been added to the driver. Since some of +the Controls and startup-options are ALSA-Standard and only the +special Controls are described and discussed below. + + +Hardware functionality +====================== + +Audio transmission +------------------ + +* number of channels -- depends on transmission mode + + The number of channels chosen is from 1..Nmax. The reason to + use for a lower number of channels is only resource allocation, + since unused DMA channels are disabled and less memory is + allocated. So also the throughput of the PCI system can be + scaled. (Only important for low performance boards). + +* Single Speed -- 1..64 channels + +.. note:: + (Note: Choosing the 56channel mode for transmission or as + receiver, only 56 are transmitted/received over the MADI, but + all 64 channels are available for the mixer, so channel count + for the driver) + +* Double Speed -- 1..32 channels + +.. note:: + Note: Choosing the 56-channel mode for + transmission/receive-mode , only 28 are transmitted/received + over the MADI, but all 32 channels are available for the mixer, + so channel count for the driver + + +* Quad Speed -- 1..16 channels + +.. note:: + Choosing the 56-channel mode for + transmission/receive-mode , only 14 are transmitted/received + over the MADI, but all 16 channels are available for the mixer, + so channel count for the driver + +* Format -- signed 32 Bit Little Endian (SNDRV_PCM_FMTBIT_S32_LE) + +* Sample Rates -- + + Single Speed -- 32000, 44100, 48000 + + Double Speed -- 64000, 88200, 96000 (untested) + + Quad Speed -- 128000, 176400, 192000 (untested) + +* access-mode -- MMAP (memory mapped), Not interleaved (PCM_NON-INTERLEAVED) + +* buffer-sizes -- 64,128,256,512,1024,2048,8192 Samples + +* fragments -- 2 + +* Hardware-pointer -- 2 Modi + + + The Card supports the readout of the actual Buffer-pointer, + where DMA reads/writes. Since of the bulk mode of PCI it is only + 64 Byte accurate. SO it is not really usable for the + ALSA-mid-level functions (here the buffer-ID gives a better + result), but if MMAP is used by the application. Therefore it + can be configured at load-time with the parameter + precise-pointer. + + +.. hint:: + (Hint: Experimenting I found that the pointer is maximum 64 to + large never to small. So if you subtract 64 you always have a + safe pointer for writing, which is used on this mode inside + ALSA. In theory now you can get now a latency as low as 16 + Samples, which is a quarter of the interrupt possibilities.) + + * Precise Pointer -- off + interrupt used for pointer-calculation + + * Precise Pointer -- on + hardware pointer used. + +Controller +---------- + +Since DSP-MADI-Mixer has 8152 Fader, it does not make sense to +use the standard mixer-controls, since this would break most of +(especially graphic) ALSA-Mixer GUIs. So Mixer control has be +provided by a 2-dimensional controller using the +hwdep-interface. + +Also all 128+256 Peak and RMS-Meter can be accessed via the +hwdep-interface. Since it could be a performance problem always +copying and converting Peak and RMS-Levels even if you just need +one, I decided to export the hardware structure, so that of +needed some driver-guru can implement a memory-mapping of mixer +or peak-meters over ioctl, or also to do only copying and no +conversion. A test-application shows the usage of the controller. + +* Latency Controls --- not implemented !!! + +.. note:: + Note: Within the windows-driver the latency is accessible of a + control-panel, but buffer-sizes are controlled with ALSA from + hwparams-calls and should not be changed in run-state, I did not + implement it here. + + +* System Clock -- suspended !!!! + + * Name -- "System Clock Mode" + + * Access -- Read Write + + * Values -- "Master" "Slave" + +.. note:: + !!!! This is a hardware-function but is in conflict with the + Clock-source controller, which is a kind of ALSA-standard. I + makes sense to set the card to a special mode (master at some + frequency or slave), since even not using an Audio-application + a studio should have working synchronisations setup. So use + Clock-source-controller instead !!!! + +* Clock Source + + * Name -- "Sample Clock Source" + + * Access -- Read Write + + * Values -- "AutoSync", "Internal 32.0 kHz", "Internal 44.1 kHz", + "Internal 48.0 kHz", "Internal 64.0 kHz", "Internal 88.2 kHz", + "Internal 96.0 kHz" + + Choose between Master at a specific Frequency and so also the + Speed-mode or Slave (Autosync). Also see "Preferred Sync Ref" + +.. warning:: + !!!! This is no pure hardware function but was implemented by + ALSA by some ALSA-drivers before, so I use it also. !!! + + +* Preferred Sync Ref + + * Name -- "Preferred Sync Reference" + + * Access -- Read Write + + * Values -- "Word" "MADI" + + + Within the Auto-sync-Mode the preferred Sync Source can be + chosen. If it is not available another is used if possible. + +.. note:: + Note: Since MADI has a much higher bit-rate than word-clock, the + card should synchronise better in MADI Mode. But since the + RME-PLL is very good, there are almost no problems with + word-clock too. I never found a difference. + + +* TX 64 channel + + * Name -- "TX 64 channels mode" + + * Access -- Read Write + + * Values -- 0 1 + + Using 64-channel-modus (1) or 56-channel-modus for + MADI-transmission (0). + + +.. note:: + Note: This control is for output only. Input-mode is detected + automatically from hardware sending MADI. + + +* Clear TMS + + * Name -- "Clear Track Marker" + + * Access -- Read Write + + * Values -- 0 1 + + + Don't use to lower 5 Audio-bits on AES as additional Bits. + + +* Safe Mode oder Auto Input + + * Name -- "Safe Mode" + + * Access -- Read Write + + * Values -- 0 1 (default on) + + If on (1), then if either the optical or coaxial connection + has a failure, there is a takeover to the working one, with no + sample failure. Its only useful if you use the second as a + backup connection. + +* Input + + * Name -- "Input Select" + + * Access -- Read Write + + * Values -- optical coaxial + + + Choosing the Input, optical or coaxial. If Safe-mode is active, + this is the preferred Input. + +Mixer +----- + +* Mixer + + * Name -- "Mixer" + + * Access -- Read Write + + * Values - <channel-number 0-127> <Value 0-65535> + + + Here as a first value the channel-index is taken to get/set the + corresponding mixer channel, where 0-63 are the input to output + fader and 64-127 the playback to outputs fader. Value 0 + is channel muted 0 and 32768 an amplification of 1. + +* Chn 1-64 + + fast mixer for the ALSA-mixer utils. The diagonal of the + mixer-matrix is implemented from playback to output. + + +* Line Out + + * Name -- "Line Out" + + * Access -- Read Write + + * Values -- 0 1 + + Switching on and off the analog out, which has nothing to do + with mixing or routing. the analog outs reflects channel 63,64. + + +Information (only read access) +------------------------------ + +* Sample Rate + + * Name -- "System Sample Rate" + + * Access -- Read-only + + getting the sample rate. + + +* External Rate measured + + * Name -- "External Rate" + + * Access -- Read only + + + Should be "Autosync Rate", but Name used is + ALSA-Scheme. External Sample frequency liked used on Autosync is + reported. + + +* MADI Sync Status + + * Name -- "MADI Sync Lock Status" + + * Access -- Read + + * Values -- 0,1,2 + + MADI-Input is 0=Unlocked, 1=Locked, or 2=Synced. + + +* Word Clock Sync Status + + * Name -- "Word Clock Lock Status" + + * Access -- Read + + * Values -- 0,1,2 + + Word Clock Input is 0=Unlocked, 1=Locked, or 2=Synced. + +* AutoSync + + * Name -- "AutoSync Reference" + + * Access -- Read + + * Values -- "WordClock", "MADI", "None" + + Sync-Reference is either "WordClock", "MADI" or none. + +* RX 64ch --- noch nicht implementiert + + MADI-Receiver is in 64 channel mode oder 56 channel mode. + + +* AB_inp --- not tested + + Used input for Auto-Input. + + +* actual Buffer Position --- not implemented + + !!! this is a ALSA internal function, so no control is used !!! + + + +Calling Parameter +================= + +* index int array (min = 1, max = 8) + + Index value for RME HDSPM interface. card-index within ALSA + + note: ALSA-standard + +* id string array (min = 1, max = 8) + + ID string for RME HDSPM interface. + + note: ALSA-standard + +* enable int array (min = 1, max = 8) + + Enable/disable specific HDSPM sound-cards. + + note: ALSA-standard + +* precise_ptr int array (min = 1, max = 8) + + Enable precise pointer, or disable. + +.. note:: + note: Use only when the application supports this (which is a special case). + +* line_outs_monitor int array (min = 1, max = 8) + + Send playback streams to analog outs by default. + +.. note:: + note: each playback channel is mixed to the same numbered output + channel (routed). This is against the ALSA-convention, where all + channels have to be muted on after loading the driver, but was + used before on other cards, so i historically use it again) + + + +* enable_monitor int array (min = 1, max = 8) + + Enable Analog Out on Channel 63/64 by default. + +.. note :: + note: here the analog output is enabled (but not routed). |