ALSA: hda: option to enable arbitrary buffer/period sizes
Add new parameter to disable rounding of buffer/period sizes to
multiples of 128 bytes. This is more efficient in terms of memory
access but isn't required by the HDA spec and prevents users from
specifying exact period/buffer sizes. For example for 44.1kHz, a
period size set to 20ms will be rounded to 19.59ms.
Tested and enabled on Intel HDA controllers. Option is disabled by
default for other controllers.
Tested-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt
index 8975701..27126c4 100644
--- a/Documentation/sound/alsa/ALSA-Configuration.txt
+++ b/Documentation/sound/alsa/ALSA-Configuration.txt
@@ -886,6 +886,11 @@
disable)
power_save_controller - Reset HD-audio controller in power-saving mode
(default = on)
+ align_buffer_size - Force rounding of buffer/period sizes to multiples
+ of 128 bytes. This is more efficient in terms of memory
+ access but isn't required by the HDA spec and prevents
+ users from specifying exact period/buffer sizes.
+ (default = on)
This module supports multiple cards and autoprobe.