[PATCH 3.16.y-ckt 056/144] ALSA: hda - Treat stereo-to-mono mix properly

From: Luis Henriques
Date: Tue Apr 21 2015 - 12:15:00 EST


3.16.7-ckt10 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Takashi Iwai <tiwai@xxxxxxx>

commit cc261738add93947d138d2fabad9f4dbed4e5c00 upstream.

The commit [ef403edb7558: ALSA: hda - Don't access stereo amps for
mono channel widgets] fixed the handling of mono widgets in general,
but it still misses an exceptional case: namely, a mono mixer widget
taking a single stereo input. In this case, it has stereo volumes
although it's a mono widget, and thus we have to take care of both
left and right input channels, as stated in HD-audio spec ("7.1.3
Widget Interconnection Rules").

This patch covers this missing piece by adding proper checks of stereo
amps in both the generic parser and the proc output codes.

Reported-by: Raymond Yau <superquad.vortex2@xxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
sound/pci/hda/hda_generic.c | 21 +++++++++++++++++++--
sound/pci/hda/hda_proc.c | 38 ++++++++++++++++++++++++++++++--------
2 files changed, 49 insertions(+), 10 deletions(-)

diff --git a/sound/pci/hda/hda_generic.c b/sound/pci/hda/hda_generic.c
index b756dd2906e4..0882f060696d 100644
--- a/sound/pci/hda/hda_generic.c
+++ b/sound/pci/hda/hda_generic.c
@@ -653,13 +653,30 @@ static int get_amp_val_to_activate(struct hda_codec *codec, hda_nid_t nid,
return val;
}

+/* is this a stereo widget or a stereo-to-mono mix? */
+static bool is_stereo_amps(struct hda_codec *codec, hda_nid_t nid, int dir)
+{
+ unsigned int wcaps = get_wcaps(codec, nid);
+ hda_nid_t conn;
+
+ if (wcaps & AC_WCAP_STEREO)
+ return true;
+ if (dir != HDA_INPUT || get_wcaps_type(wcaps) != AC_WID_AUD_MIX)
+ return false;
+ if (snd_hda_get_num_conns(codec, nid) != 1)
+ return false;
+ if (snd_hda_get_connections(codec, nid, &conn, 1) < 0)
+ return false;
+ return !!(get_wcaps(codec, conn) & AC_WCAP_STEREO);
+}
+
/* initialize the amp value (only at the first time) */
static void init_amp(struct hda_codec *codec, hda_nid_t nid, int dir, int idx)
{
unsigned int caps = query_amp_caps(codec, nid, dir);
int val = get_amp_val_to_activate(codec, nid, dir, caps, false);

- if (get_wcaps(codec, nid) & AC_WCAP_STEREO)
+ if (is_stereo_amps(codec, nid, dir))
snd_hda_codec_amp_init_stereo(codec, nid, dir, idx, 0xff, val);
else
snd_hda_codec_amp_init(codec, nid, 0, dir, idx, 0xff, val);
@@ -669,7 +686,7 @@ static void init_amp(struct hda_codec *codec, hda_nid_t nid, int dir, int idx)
static int update_amp(struct hda_codec *codec, hda_nid_t nid, int dir, int idx,
unsigned int mask, unsigned int val)
{
- if (get_wcaps(codec, nid) & AC_WCAP_STEREO)
+ if (is_stereo_amps(codec, nid, dir))
return snd_hda_codec_amp_stereo(codec, nid, dir, idx,
mask, val);
else
diff --git a/sound/pci/hda/hda_proc.c b/sound/pci/hda/hda_proc.c
index ce5a6da83419..05e19f78b4cb 100644
--- a/sound/pci/hda/hda_proc.c
+++ b/sound/pci/hda/hda_proc.c
@@ -134,13 +134,38 @@ static void print_amp_caps(struct snd_info_buffer *buffer,
(caps & AC_AMPCAP_MUTE) >> AC_AMPCAP_MUTE_SHIFT);
}

+/* is this a stereo widget or a stereo-to-mono mix? */
+static bool is_stereo_amps(struct hda_codec *codec, hda_nid_t nid,
+ int dir, unsigned int wcaps, int indices)
+{
+ hda_nid_t conn;
+
+ if (wcaps & AC_WCAP_STEREO)
+ return true;
+ /* check for a stereo-to-mono mix; it must be:
+ * only a single connection, only for input, and only a mixer widget
+ */
+ if (indices != 1 || dir != HDA_INPUT ||
+ get_wcaps_type(wcaps) != AC_WID_AUD_MIX)
+ return false;
+
+ if (snd_hda_get_raw_connections(codec, nid, &conn, 1) < 0)
+ return false;
+ /* the connection source is a stereo? */
+ wcaps = snd_hda_param_read(codec, conn, AC_PAR_AUDIO_WIDGET_CAP);
+ return !!(wcaps & AC_WCAP_STEREO);
+}
+
static void print_amp_vals(struct snd_info_buffer *buffer,
struct hda_codec *codec, hda_nid_t nid,
- int dir, int stereo, int indices)
+ int dir, unsigned int wcaps, int indices)
{
unsigned int val;
+ bool stereo;
int i;

+ stereo = is_stereo_amps(codec, nid, dir, wcaps, indices);
+
dir = dir == HDA_OUTPUT ? AC_AMP_GET_OUTPUT : AC_AMP_GET_INPUT;
for (i = 0; i < indices; i++) {
snd_iprintf(buffer, " [");
@@ -757,12 +782,10 @@ static void print_codec_info(struct snd_info_entry *entry,
(codec->single_adc_amp &&
wid_type == AC_WID_AUD_IN))
print_amp_vals(buffer, codec, nid, HDA_INPUT,
- wid_caps & AC_WCAP_STEREO,
- 1);
+ wid_caps, 1);
else
print_amp_vals(buffer, codec, nid, HDA_INPUT,
- wid_caps & AC_WCAP_STEREO,
- conn_len);
+ wid_caps, conn_len);
}
if (wid_caps & AC_WCAP_OUT_AMP) {
snd_iprintf(buffer, " Amp-Out caps: ");
@@ -771,11 +794,10 @@ static void print_codec_info(struct snd_info_entry *entry,
if (wid_type == AC_WID_PIN &&
codec->pin_amp_workaround)
print_amp_vals(buffer, codec, nid, HDA_OUTPUT,
- wid_caps & AC_WCAP_STEREO,
- conn_len);
+ wid_caps, conn_len);
else
print_amp_vals(buffer, codec, nid, HDA_OUTPUT,
- wid_caps & AC_WCAP_STEREO, 1);
+ wid_caps, 1);
}

switch (wid_type) {
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/