pipewire: update to latest master

Update patches:
 * remove merged patches
 * remove the alsa algorithm correction that was needed for qemu,
   as it seems to cause severe underruns on other platforms now;
   I will recheck qemu to see if this is still an issue
 * add a workaround needed to get the audioconvert plugin running
   in merge+split mode (needed to get all the channels out instead
   of just the front left channel that we were getting before)

Update version to 0.2.91 to reflect the fact that we are now tracking
the master branch instead of the work branch.

Enable the spa audiomixer plugin which is now required to mix audio on ports

Bug-AGL: SPEC-2837

Change-Id: I2558aa5487b9c9918e077bf450230c143abf7e6c
Signed-off-by: George Kiagiadakis <george.kiagiadakis@collabora.com>

1 files changed, 37 insertions, 0 deletions

diff --git a/meta-pipewire/recipes-multimedia/pipewire/pipewire/0006-gst-pwaudiosink-set-the-default-latency-time-buffer-.patch b/meta-pipewire/recipes-multimedia/pipewire/pipewire/0006-gst-pwaudiosink-set-the-default-latency-time-buffer-.patch
new file mode 100644
index 00000000..1f56b1c4
--- /dev/null
+++ b/meta-pipewire/recipes-multimedia/pipewire/pipewire/0006-gst-pwaudiosink-set-the-default-latency-time-buffer-.patch
@@ -0,0 +1,37 @@
+From 30622ed39774d3a2d3133effbc73caac5fb12596 Mon Sep 17 00:00:00 2001
+From: George Kiagiadakis <george.kiagiadakis@collabora.com>
+Date: Thu, 11 Jul 2019 17:07:15 +0300
+Subject: [PATCH] gst/pwaudiosink: set the default latency time (buffer size)
+ to be 21.3ms
+
+This is to solve underrun issues that seem to appear with the default
+10ms latency that GstBaseAudioSink has.
+Hopefully in the future we will have a better mechanism to pick
+the appropriate latency instead of hardcoding it here.
+
+Upstream-Status: Submitted [https://github.com/PipeWire/pipewire/pull/140]
+---
+ src/gst/gstpwaudiosink.c | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/src/gst/gstpwaudiosink.c b/src/gst/gstpwaudiosink.c
+index 6cb71385..069996c3 100644
+--- a/src/gst/gstpwaudiosink.c
++++ b/src/gst/gstpwaudiosink.c
+@@ -57,6 +57,13 @@ static void
+ gst_pw_audio_sink_init (GstPwAudioSink * self)
+ {
+   self->props.fd = -1;
++
++  /* Bump the default buffer size up to 21.3 ms, which is the default on most
++   * sound cards, in hope to match the alsa buffer size on the pipewire server.
++   * This may not always happen, but it still sounds better than the 10ms
++   * default latency. This is temporary until we have a better mechanism to
++   * select the appropriate latency */
++  GST_AUDIO_BASE_SINK (self)->latency_time = 21333;
+ }
+ 
+ static void
+-- 
+2.23.0
+