ALSA: hda - Fix playback noise with 24/32 bit sample size on BXT
In BXT-P A0, HD-Audio DMA requests is later than expected,
and makes an audio stream sensitive to system latencies when
24/32 bits are playing.
Adjusting threshold of DMA fifo to force the DMA request
sooner to improve latency tolerance at the expense of power.
v2: move Intel specific code to hda_intel.c
Signed-off-by: Lu, Han <han.lu@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/include/sound/hda_register.h b/include/sound/hda_register.h
index 2ae8812..94dc6a9 100644
--- a/include/sound/hda_register.h
+++ b/include/sound/hda_register.h
@@ -93,6 +93,9 @@
#define AZX_REG_HSW_EM4 0x100c
#define AZX_REG_HSW_EM5 0x1010
+/* Skylake/Broxton display HD-A controller Extended Mode registers */
+#define AZX_REG_SKL_EM4L 0x1040
+
/* PCI space */
#define AZX_PCIREG_TCSEL 0x44