[3.19.y-ckt stable] Patch "ALSA: usb-audio: Add a more accurate volume quirk for AudioQuest DragonFly" has been added to the 3.19.y-ckt tree
Kamal Mostafa
kamal at canonical.com
Wed Jan 20 01:03:26 UTC 2016
This is a note to let you know that I have just added a patch titled
ALSA: usb-audio: Add a more accurate volume quirk for AudioQuest DragonFly
to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree
which can be found at:
http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue
This patch is scheduled to be released in version 3.19.8-ckt13.
If you, or anyone else, feels it should not be added to this tree, please
reply to this email.
For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
Thanks.
-Kamal
---8<------------------------------------------------------------
>From df86d60ee2e38433146a083faa1e53f120dc2890 Mon Sep 17 00:00:00 2001
From: Anssi Hannula <anssi.hannula at iki.fi>
Date: Sun, 13 Dec 2015 20:49:58 +0200
Subject: ALSA: usb-audio: Add a more accurate volume quirk for AudioQuest
DragonFly
commit 42e3121d90f42e57f6dbd6083dff2f57b3ec7daa upstream.
AudioQuest DragonFly DAC reports a volume control range of 0..50
(0x0000..0x0032) which in USB Audio means a range of 0 .. 0.2dB, which
is obviously incorrect and would cause software using the dB information
in e.g. volume sliders to have a massive volume difference in 100..102%
range.
Commit 2d1cb7f658fb ("ALSA: usb-audio: add dB range mapping for some
devices") added a dB range mapping for it with range 0..50 dB.
However, the actual volume mapping seems to be neither linear volume nor
linear dB scale, but instead quite close to the cubic mapping e.g.
alsamixer uses, with a range of approx. -53...0 dB.
Replace the previous quirk with a custom dB mapping based on some basic
output measurements, using a 10-item range TLV (which will still fit in
alsa-lib MAX_TLV_RANGE_SIZE).
Tested on AudioQuest DragonFly HW v1.2. The quirk is only applied if the
range is 0..50, so if this gets fixed/changed in later HW revisions it
will no longer be applied.
v2: incorporated Takashi Iwai's suggestion for the quirk application
method
Signed-off-by: Anssi Hannula <anssi.hannula at iki.fi>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
sound/usb/mixer.c | 2 ++
sound/usb/mixer_maps.c | 12 ------------
sound/usb/mixer_quirks.c | 37 +++++++++++++++++++++++++++++++++++++
sound/usb/mixer_quirks.h | 4 ++++
4 files changed, 43 insertions(+), 12 deletions(-)
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index cd8ed2e..f9a9752 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -1336,6 +1336,8 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
}
}
+ snd_usb_mixer_fu_apply_quirk(state->mixer, cval, unitid, kctl);
+
range = (cval->max - cval->min) / cval->res;
/*
* Are there devices with volume range more than 255? I use a bit more
diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index 6a803ef..ddca654 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -348,13 +348,6 @@ static struct usbmix_name_map bose_companion5_map[] = {
{ 0 } /* terminator */
};
-/* Dragonfly DAC 1.2, the dB conversion factor is 1 instead of 256 */
-static struct usbmix_dB_map dragonfly_1_2_dB = {0, 5000};
-static struct usbmix_name_map dragonfly_1_2_map[] = {
- { 7, NULL, .dB = &dragonfly_1_2_dB },
- { 0 } /* terminator */
-};
-
/*
* Control map entries
*/
@@ -470,11 +463,6 @@ static struct usbmix_ctl_map usbmix_ctl_maps[] = {
.id = USB_ID(0x05a7, 0x1020),
.map = bose_companion5_map,
},
- {
- /* Dragonfly DAC 1.2 */
- .id = USB_ID(0x21b4, 0x0081),
- .map = dragonfly_1_2_map,
- },
{ 0 } /* terminator */
};
diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index 337c317..48a7450 100644
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -37,6 +37,7 @@
#include <sound/control.h>
#include <sound/hwdep.h>
#include <sound/info.h>
+#include <sound/tlv.h>
#include "usbaudio.h"
#include "mixer.h"
@@ -1843,3 +1844,39 @@ void snd_usb_mixer_rc_memory_change(struct usb_mixer_interface *mixer,
}
}
+static void snd_dragonfly_quirk_db_scale(struct usb_mixer_interface *mixer,
+ struct snd_kcontrol *kctl)
+{
+ /* Approximation using 10 ranges based on output measurement on hw v1.2.
+ * This seems close to the cubic mapping e.g. alsamixer uses. */
+ static const DECLARE_TLV_DB_RANGE(scale,
+ 0, 1, TLV_DB_MINMAX_ITEM(-5300, -4970),
+ 2, 5, TLV_DB_MINMAX_ITEM(-4710, -4160),
+ 6, 7, TLV_DB_MINMAX_ITEM(-3884, -3710),
+ 8, 14, TLV_DB_MINMAX_ITEM(-3443, -2560),
+ 15, 16, TLV_DB_MINMAX_ITEM(-2475, -2324),
+ 17, 19, TLV_DB_MINMAX_ITEM(-2228, -2031),
+ 20, 26, TLV_DB_MINMAX_ITEM(-1910, -1393),
+ 27, 31, TLV_DB_MINMAX_ITEM(-1322, -1032),
+ 32, 40, TLV_DB_MINMAX_ITEM(-968, -490),
+ 41, 50, TLV_DB_MINMAX_ITEM(-441, 0),
+ );
+
+ usb_audio_info(mixer->chip, "applying DragonFly dB scale quirk\n");
+ kctl->tlv.p = scale;
+ kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
+ kctl->vd[0].access &= ~SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
+}
+
+void snd_usb_mixer_fu_apply_quirk(struct usb_mixer_interface *mixer,
+ struct usb_mixer_elem_info *cval, int unitid,
+ struct snd_kcontrol *kctl)
+{
+ switch (mixer->chip->usb_id) {
+ case USB_ID(0x21b4, 0x0081): /* AudioQuest DragonFly */
+ if (unitid == 7 && cval->min == 0 && cval->max == 50)
+ snd_dragonfly_quirk_db_scale(mixer, kctl);
+ break;
+ }
+}
+
diff --git a/sound/usb/mixer_quirks.h b/sound/usb/mixer_quirks.h
index bdbfab0..177c329 100644
--- a/sound/usb/mixer_quirks.h
+++ b/sound/usb/mixer_quirks.h
@@ -9,5 +9,9 @@ void snd_emuusb_set_samplerate(struct snd_usb_audio *chip,
void snd_usb_mixer_rc_memory_change(struct usb_mixer_interface *mixer,
int unitid);
+void snd_usb_mixer_fu_apply_quirk(struct usb_mixer_interface *mixer,
+ struct usb_mixer_elem_info *cval, int unitid,
+ struct snd_kcontrol *kctl);
+
#endif /* SND_USB_MIXER_QUIRKS_H */
--
1.9.1
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