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author | Jaroslav Kysela <perex@perex.cz> | 2022-05-19 10:18:38 +0200 |
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committer | Jaroslav Kysela <perex@perex.cz> | 2022-05-19 10:18:38 +0200 |
commit | 2389f04541ad7767c5499b672f7d86d133ba117e (patch) | |
tree | 5fd1fead14e0f17893f2dd22a9227b7411f20787 | |
parent | 4b66e5fbce3836d7203d2c922edf24ad7737faee (diff) | |
download | alsa-lib-2389f04541ad7767c5499b672f7d86d133ba117e.tar.gz |
ucm: doc - describe variants, minor corrections
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
-rw-r--r-- | src/ucm/ucm_confdoc.h | 39 |
1 files changed, 37 insertions, 2 deletions
diff --git a/src/ucm/ucm_confdoc.h b/src/ucm/ucm_confdoc.h index 31ec0c59..dbaf93af 100644 --- a/src/ucm/ucm_confdoc.h +++ b/src/ucm/ucm_confdoc.h @@ -389,7 +389,7 @@ ${find-device:<str>} | Find a device - see _Find device substitution_ section Substituted string | Value ---------------------|--------------------- -${evali:<str>} | Evaluate expression like *($var+2)/3* [**Syntax 5**]; target node will be integer; substituted only in the LibraryConfig subtree +${evali:<str>} | Evaluate expression like *($var+2)/3* [**Syntax 6**]; target node will be integer; substituted only in the LibraryConfig subtree #### Find card substitution @@ -456,7 +456,7 @@ Variables can be substituted using the `${var:rval1}` reference for example. ### Macros -Macros were added for *Syntax* version *5*. The *DefineMacro* defines new +Macros were added for *Syntax* version *6*. The *DefineMacro* defines new macro like: ~~~{.html} @@ -566,6 +566,41 @@ If.fmic { } ~~~ +### Variants + +To avoid duplication of the many configuration files for the cases with +minimal configuration changes, there is the variant extension. Variants were +added for *Syntax* version *6*. + +The bellow example will create two verbs - "HiFi" and "HiFi 7.1" with +the different playback channels (2 and 8) for the "Speaker" device. + +Example (main configuration file): + +~~~{.html} +SectionUseCase."HiFi" { + File "HiFi.conf" + Variant."HiFi" { + Comment "HiFi" + } + Variant."HiFi 7+1" { + Comment "HiFi 7.1" + } +} +~~~ + +Example (verb configuration file - HiFi.conf): + +~~~{.html} +SectionDevice."Speaker" { + Value { + PlaybackChannels 2 + } + Variant."HiFi 7+1".Value { + PlaybackChannels 8 + } +} +~~~ */ |