From 025f206c9e0f96cc41567b01c07fb852d8900da1 Mon Sep 17 00:00:00 2001
From: Daniel T Chen <crimsun@ubuntu.com>
Date: Sun, 21 Mar 2010 18:34:43 -0400
Subject: [PATCH] ALSA: hda: Fix 0 dB offset for HP laptops using CX20551
(Waikiki)
BugLink: https://launchpad.net/bugs/420578
The OR has verified that his hardware distorts because of the 0 dB
offset not corresponding to the highest PCM level. Fix this by capping
said PCM level to 0 dB similarly to what we do for CX20549 (Venice).
Reported-by: Mike Pontillo <pontillo@gmail.com>
Tested-by: Mike Pontillo <pontillo@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Daniel T Chen <crimsun@ubuntu.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
sound/pci/hda/patch_conexant.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/sound/pci/hda/patch_conexant.c b/sound/pci/hda/patch_conexant.c
index 194a28c54992..61682e1d09da 100644
--- a/sound/pci/hda/patch_conexant.c
+++ b/sound/pci/hda/patch_conexant.c
@@ -1591,6 +1591,21 @@ static int patch_cxt5047(struct hda_codec *codec)
#endif
}
spec->vmaster_nid = 0x13;
+
+ switch (codec->subsystem_id >> 16) {
+ case 0x103c:
+ /* HP laptops have really bad sound over 0 dB on NID 0x10.
+ * Fix max PCM level to 0 dB (originally it has 0x1e steps
+ * with 0 dB offset 0x17)
+ */
+ snd_hda_override_amp_caps(codec, 0x10, HDA_INPUT,
+ (0x17 << AC_AMPCAP_OFFSET_SHIFT) |
+ (0x17 << AC_AMPCAP_NUM_STEPS_SHIFT) |
+ (0x05 << AC_AMPCAP_STEP_SIZE_SHIFT) |
+ (1 << AC_AMPCAP_MUTE_SHIFT));
+ break;
+ }
+
return 0;
}