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authorTakashi Iwai <tiwai@suse.de>2009-09-10 15:32:51 +0200
committerTakashi Iwai <tiwai@suse.de>2009-09-10 15:32:51 +0200
commit6a0f4021469727675b83d85ac91d106bfae0e2c3 (patch)
treec6d7ffd99db592f4b7c294d1a5a7b54284012673 /Documentation/sound/alsa/ALSA-Configuration.txt
parentMerge branch 'topic/dma-sgbuf' into for-linus (diff)
parentALSA: dummy - Increase MAX_PCM_SUBSTREAMS to 128 (diff)
downloadlinux-6a0f4021469727675b83d85ac91d106bfae0e2c3.tar.xz
linux-6a0f4021469727675b83d85ac91d106bfae0e2c3.zip
Merge branch 'topic/dummy' into for-linus
* topic/dummy: ALSA: dummy - Increase MAX_PCM_SUBSTREAMS to 128 ALSA: dummy - Add debug proc file ALSA: Add const prefix to proc helper functions ALSA: Re-export snd_pcm_format_name() function ALSA: dummy - Fake buffer allocations ALSA: dummy - Fix the timer calculation in systimer mode ALSA: dummy - Add more description ALSA: dummy - Better jiffies handling ALSA: dummy - Support high-res timer mode
Diffstat (limited to 'Documentation/sound/alsa/ALSA-Configuration.txt')
-rw-r--r--Documentation/sound/alsa/ALSA-Configuration.txt20
1 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt
index 4252697a95d6..ea16e7d184a4 100644
--- a/Documentation/sound/alsa/ALSA-Configuration.txt
+++ b/Documentation/sound/alsa/ALSA-Configuration.txt
@@ -513,6 +513,26 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
or input, but you may use this module for any application which
requires a sound card (like RealPlayer).
+ pcm_devs - Number of PCM devices assigned to each card
+ (default = 1, up to 4)
+ pcm_substreams - Number of PCM substreams assigned to each PCM
+ (default = 8, up to 16)
+ hrtimer - Use hrtimer (=1, default) or system timer (=0)
+ fake_buffer - Fake buffer allocations (default = 1)
+
+ When multiple PCM devices are created, snd-dummy gives different
+ behavior to each PCM device:
+ 0 = interleaved with mmap support
+ 1 = non-interleaved with mmap support
+ 2 = interleaved without mmap
+ 3 = non-interleaved without mmap
+
+ As default, snd-dummy drivers doesn't allocate the real buffers
+ but either ignores read/write or mmap a single dummy page to all
+ buffer pages, in order to save the resouces. If your apps need
+ the read/ written buffer data to be consistent, pass fake_buffer=0
+ option.
+
The power-management is supported.
Module snd-echo3g