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1=======================================2Software Interface ALSA-DSP MADI Driver 3=======================================4 5(translated from German, so no good English ;-), 6 72004 - winfried ritsch8 9 10Full functionality has been added to the driver. Since some of11the Controls and startup-options are ALSA-Standard and only the12special Controls are described and discussed below.13 14 15Hardware functionality16======================17 18Audio transmission19------------------20 21* number of channels -- depends on transmission mode22 23 The number of channels chosen is from 1..Nmax. The reason to24 use for a lower number of channels is only resource allocation,25 since unused DMA channels are disabled and less memory is26 allocated. So also the throughput of the PCI system can be27 scaled. (Only important for low performance boards).28 29* Single Speed -- 1..64 channels 30 31.. note::32 (Note: Choosing the 56channel mode for transmission or as33 receiver, only 56 are transmitted/received over the MADI, but34 all 64 channels are available for the mixer, so channel count35 for the driver)36 37* Double Speed -- 1..32 channels38 39.. note::40 Note: Choosing the 56-channel mode for41 transmission/receive-mode , only 28 are transmitted/received42 over the MADI, but all 32 channels are available for the mixer,43 so channel count for the driver44 45 46* Quad Speed -- 1..16 channels 47 48.. note::49 Choosing the 56-channel mode for50 transmission/receive-mode , only 14 are transmitted/received51 over the MADI, but all 16 channels are available for the mixer,52 so channel count for the driver53 54* Format -- signed 32 Bit Little Endian (SNDRV_PCM_FMTBIT_S32_LE)55 56* Sample Rates --57 58 Single Speed -- 32000, 44100, 4800059 60 Double Speed -- 64000, 88200, 96000 (untested)61 62 Quad Speed -- 128000, 176400, 192000 (untested)63 64* access-mode -- MMAP (memory mapped), Not interleaved (PCM_NON-INTERLEAVED)65 66* buffer-sizes -- 64,128,256,512,1024,2048,8192 Samples67 68* fragments -- 269 70* Hardware-pointer -- 2 Modi71 72 73 The Card supports the readout of the actual Buffer-pointer,74 where DMA reads/writes. Since of the bulk mode of PCI it is only75 64 Byte accurate. SO it is not really usable for the76 ALSA-mid-level functions (here the buffer-ID gives a better77 result), but if MMAP is used by the application. Therefore it78 can be configured at load-time with the parameter79 precise-pointer.80 81 82.. hint::83 (Hint: Experimenting I found that the pointer is maximum 64 to84 large never to small. So if you subtract 64 you always have a85 safe pointer for writing, which is used on this mode inside86 ALSA. In theory now you can get now a latency as low as 1687 Samples, which is a quarter of the interrupt possibilities.)88 89 * Precise Pointer -- off90 interrupt used for pointer-calculation91 92 * Precise Pointer -- on93 hardware pointer used.94 95Controller96----------97 98Since DSP-MADI-Mixer has 8152 Fader, it does not make sense to99use the standard mixer-controls, since this would break most of100(especially graphic) ALSA-Mixer GUIs. So Mixer control has be101provided by a 2-dimensional controller using the102hwdep-interface. 103 104Also all 128+256 Peak and RMS-Meter can be accessed via the105hwdep-interface. Since it could be a performance problem always106copying and converting Peak and RMS-Levels even if you just need107one, I decided to export the hardware structure, so that of108needed some driver-guru can implement a memory-mapping of mixer109or peak-meters over ioctl, or also to do only copying and no110conversion. A test-application shows the usage of the controller.111 112* Latency Controls --- not implemented !!!113 114.. note::115 Note: Within the windows-driver the latency is accessible of a116 control-panel, but buffer-sizes are controlled with ALSA from117 hwparams-calls and should not be changed in run-state, I did not118 implement it here.119 120 121* System Clock -- suspended !!!!122 123 * Name -- "System Clock Mode"124 125 * Access -- Read Write126 127 * Values -- "Master" "Slave"128 129.. note::130 !!!! This is a hardware-function but is in conflict with the131 Clock-source controller, which is a kind of ALSA-standard. I132 makes sense to set the card to a special mode (master at some133 frequency or slave), since even not using an Audio-application134 a studio should have working synchronisations setup. So use135 Clock-source-controller instead !!!!136 137* Clock Source 138 139 * Name -- "Sample Clock Source"140 141 * Access -- Read Write142 143 * Values -- "AutoSync", "Internal 32.0 kHz", "Internal 44.1 kHz",144 "Internal 48.0 kHz", "Internal 64.0 kHz", "Internal 88.2 kHz",145 "Internal 96.0 kHz"146 147 Choose between Master at a specific Frequency and so also the148 Speed-mode or Slave (Autosync). Also see "Preferred Sync Ref"149 150.. warning::151 !!!! This is no pure hardware function but was implemented by152 ALSA by some ALSA-drivers before, so I use it also. !!!153 154 155* Preferred Sync Ref156 157 * Name -- "Preferred Sync Reference"158 159 * Access -- Read Write160 161 * Values -- "Word" "MADI"162 163 164 Within the Auto-sync-Mode the preferred Sync Source can be165 chosen. If it is not available another is used if possible.166 167.. note::168 Note: Since MADI has a much higher bit-rate than word-clock, the169 card should synchronise better in MADI Mode. But since the170 RME-PLL is very good, there are almost no problems with171 word-clock too. I never found a difference.172 173 174* TX 64 channel175 176 * Name -- "TX 64 channels mode"177 178 * Access -- Read Write179 180 * Values -- 0 1181 182 Using 64-channel-modus (1) or 56-channel-modus for183 MADI-transmission (0).184 185 186.. note::187 Note: This control is for output only. Input-mode is detected188 automatically from hardware sending MADI.189 190 191* Clear TMS192 193 * Name -- "Clear Track Marker"194 195 * Access -- Read Write196 197 * Values -- 0 1198 199 200 Don't use to lower 5 Audio-bits on AES as additional Bits.201 202 203* Safe Mode oder Auto Input204 205 * Name -- "Safe Mode"206 207 * Access -- Read Write208 209 * Values -- 0 1 (default on)210 211 If on (1), then if either the optical or coaxial connection212 has a failure, there is a takeover to the working one, with no213 sample failure. Its only useful if you use the second as a214 backup connection.215 216* Input217 218 * Name -- "Input Select"219 220 * Access -- Read Write221 222 * Values -- optical coaxial223 224 225 Choosing the Input, optical or coaxial. If Safe-mode is active,226 this is the preferred Input.227 228Mixer229-----230 231* Mixer232 233 * Name -- "Mixer"234 235 * Access -- Read Write236 237 * Values - <channel-number 0-127> <Value 0-65535>238 239 240 Here as a first value the channel-index is taken to get/set the241 corresponding mixer channel, where 0-63 are the input to output242 fader and 64-127 the playback to outputs fader. Value 0243 is channel muted 0 and 32768 an amplification of 1.244 245* Chn 1-64246 247 fast mixer for the ALSA-mixer utils. The diagonal of the248 mixer-matrix is implemented from playback to output.249 250 251* Line Out252 253 * Name -- "Line Out"254 255 * Access -- Read Write256 257 * Values -- 0 1258 259 Switching on and off the analog out, which has nothing to do260 with mixing or routing. the analog outs reflects channel 63,64.261 262 263Information (only read access)264------------------------------265 266* Sample Rate267 268 * Name -- "System Sample Rate"269 270 * Access -- Read-only271 272 getting the sample rate.273 274 275* External Rate measured276 277 * Name -- "External Rate"278 279 * Access -- Read only280 281 282 Should be "Autosync Rate", but Name used is283 ALSA-Scheme. External Sample frequency liked used on Autosync is284 reported.285 286 287* MADI Sync Status288 289 * Name -- "MADI Sync Lock Status"290 291 * Access -- Read292 293 * Values -- 0,1,2294 295 MADI-Input is 0=Unlocked, 1=Locked, or 2=Synced.296 297 298* Word Clock Sync Status299 300 * Name -- "Word Clock Lock Status"301 302 * Access -- Read303 304 * Values -- 0,1,2305 306 Word Clock Input is 0=Unlocked, 1=Locked, or 2=Synced.307 308* AutoSync309 310 * Name -- "AutoSync Reference"311 312 * Access -- Read313 314 * Values -- "WordClock", "MADI", "None"315 316 Sync-Reference is either "WordClock", "MADI" or none.317 318* RX 64ch --- noch nicht implementiert319 320 MADI-Receiver is in 64 channel mode oder 56 channel mode.321 322 323* AB_inp --- not tested 324 325 Used input for Auto-Input.326 327 328* actual Buffer Position --- not implemented329 330 !!! this is a ALSA internal function, so no control is used !!!331 332 333 334Calling Parameter335=================336 337* index int array (min = 1, max = 8) 338 339 Index value for RME HDSPM interface. card-index within ALSA340 341 note: ALSA-standard342 343* id string array (min = 1, max = 8) 344 345 ID string for RME HDSPM interface.346 347 note: ALSA-standard348 349* enable int array (min = 1, max = 8)350 351 Enable/disable specific HDSPM sound-cards.352 353 note: ALSA-standard354 355* precise_ptr int array (min = 1, max = 8)356 357 Enable precise pointer, or disable.358 359.. note::360 note: Use only when the application supports this (which is a special case).361 362* line_outs_monitor int array (min = 1, max = 8)363 364 Send playback streams to analog outs by default.365 366.. note::367 note: each playback channel is mixed to the same numbered output368 channel (routed). This is against the ALSA-convention, where all369 channels have to be muted on after loading the driver, but was370 used before on other cards, so i historically use it again)371 372 373 374* enable_monitor int array (min = 1, max = 8)375 376 Enable Analog Out on Channel 63/64 by default.377 378.. note ::379 note: here the analog output is enabled (but not routed).380