[alsa-devel] [PATCH 2/2] ALSA: hda - add sanity check to force the separate stream tags

[Jaroslav Kysela]

It seems that newer Intel chipsets have more than 15 I/O streams (total).
This patch forces the separate stream tags, when this hardware is detected
to avoid SDxCTL.STRM field overflow and an unexpected behaviour.

Signed-off-by: Jaroslav Kysela <perex at perex.cz>
---
 sound/pci/hda/hda_intel.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 7d77bb5..16108f0e 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -1778,6 +1778,14 @@ static int azx_first_init(struct azx *chip)
 	chip->playback_index_offset = chip->capture_streams;
 	chip->num_streams = chip->playback_streams + chip->capture_streams;
 
+	/* sanity check for the SDxCTL.STRM field overflow */
+	if (chip->num_streams > 15 &&
+	    (chip->driver_caps & AZX_DCAPS_SEPARATE_STREAM_TAG) == 0) {
+		dev_warn(chip->card->dev, "number of I/O streams is %d, "
+			 "forcing separate stream tags", chip->num_streams);
+		chip->driver_caps |= AZX_DCAPS_SEPARATE_STREAM_TAG;
+	}
+
 	/* initialize streams */
 	err = azx_init_streams(chip);
 	if (err < 0)
-- 
2.9.3