[ALSA] Add description about probe_mask option for snd-hda-intel
Added a brief description about probe_mask option for snd-hda-intel.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt
index 297ff0d..32124bf 100644
--- a/Documentation/sound/alsa/ALSA-Configuration.txt
+++ b/Documentation/sound/alsa/ALSA-Configuration.txt
@@ -759,6 +759,7 @@
model - force the model name
position_fix - Fix DMA pointer (0 = auto, 1 = none, 2 = POSBUF, 3 = FIFO size)
+ probe_mask - Bitmask to probe codecs (default = -1, meaning all slots)
single_cmd - Use single immediate commands to communicate with
codecs (for debugging only)
enable_msi - Enable Message Signaled Interrupt (MSI) (default = off)
@@ -966,6 +967,17 @@
from the irq. Remember this is a last resort, and should be
avoided as much as possible...
+ MORE NOTES ON "azx_get_response timeout" PROBLEMS:
+ On some hardwares, you may need to add a proper probe_mask option
+ to avoid the "azx_get_response timeout" problem above, instead.
+ This occurs when the access to non-existing or non-working codec slot
+ (likely a modem one) causes a stall of the communication via HD-audio
+ bus. You can see which codec slots are probed by enabling
+ CONFIG_SND_DEBUG_DETECT, or simply from the file name of the codec
+ proc files. Then limit the slots to probe by probe_mask option.
+ For example, probe_mask=1 means to probe only the first slot, and
+ probe_mask=4 means only the third slot.
+
The power-management is supported.
Module snd-hdsp
