[pulseaudio-commits] Branch 'next' - src/modules

[Tanu Kaskinen]

 src/modules/bluetooth/backend-native.c |   28 ++++++++++++++++++----------
 1 file changed, 18 insertions(+), 10 deletions(-)

New commits:
commit 15cf273ed89f2fc6a0271eed494a489f8ca4f56a
Author: Renjith Thomas <renjith at lightlevitate.com>
Date:   Thu Dec 15 12:34:14 2016 +0530

    bluetooth: fix distorted audio during Bluetooth SCO HFP/HSP playback
    
    Issue: When HFP/HSP profile is used with certain BT chipsets, the
    audio sounds heavily distorted, with very slow playback full of noise.
    During recording, the samples are dropped and it distorts the recorded
    audio samples.
    
    The root cause of both the issues are related to the fixed MTU sizes
    in the PA stack, which is 48 bytes. Here, the BT chipset CC256x had
    180 bytes MTU and it was being under-utilized and the rate at which
    the samples were being accepted where not matching the expected rate,
    and hence the distortion.
    
    Solution: The appropriate solution to this problem is by reading the
    MTU size of the SCO socket using getsockopts dynamically.
    
    BugLink: http://bit.ly/2gDpGPv
    BugLink: http://bit.ly/2hQsARK

diff --git a/src/modules/bluetooth/backend-native.c b/src/modules/bluetooth/backend-native.c
index cf88126..4974c3f 100644
--- a/src/modules/bluetooth/backend-native.c
+++ b/src/modules/bluetooth/backend-native.c
@@ -103,6 +103,8 @@ static pa_dbus_pending* send_and_add_to_pending(pa_bluetooth_backend *backend, D
 static int bluez5_sco_acquire_cb(pa_bluetooth_transport *t, bool optional, size_t *imtu, size_t *omtu) {
     pa_bluetooth_device *d = t->device;
     struct sockaddr_sco addr;
+    struct sco_options sco_opt;
+    socklen_t len;
     int err, i;
     int sock;
     bdaddr_t src;
@@ -124,34 +126,40 @@ static int bluez5_sco_acquire_cb(pa_bluetooth_transport *t, bool optional, size_
         return -1;
     }
 
-    memset(&addr, 0, sizeof(addr));
+    len = sizeof(addr);
+    memset(&addr, 0, len);
     addr.sco_family = AF_BLUETOOTH;
     bacpy(&addr.sco_bdaddr, &src);
 
-    if (bind(sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
+    if (bind(sock, (struct sockaddr *) &addr, len) < 0) {
         pa_log_error("bind(): %s", pa_cstrerror(errno));
         goto fail_close;
     }
 
-    memset(&addr, 0, sizeof(addr));
+    memset(&addr, 0, len);
     addr.sco_family = AF_BLUETOOTH;
     bacpy(&addr.sco_bdaddr, &dst);
 
     pa_log_info("doing connect");
-    err = connect(sock, (struct sockaddr *) &addr, sizeof(addr));
+    err = connect(sock, (struct sockaddr *) &addr, len);
     if (err < 0 && !(errno == EAGAIN || errno == EINPROGRESS)) {
         pa_log_error("connect(): %s", pa_cstrerror(errno));
         goto fail_close;
     }
 
-    /* The "48" below is hardcoded until we get meaningful MTU values exposed
-     * by the kernel */
+    len = sizeof(sco_opt);
+    memset(&sco_opt, 0, len);
 
-    if (imtu)
-        *imtu = 48;
+    if (getsockopt(sock, SOL_SCO, SCO_OPTIONS, &sco_opt, &len) < 0) {
+        pa_log_warn("getsockopt(SCO_OPTIONS) failed, loading defaults");
 
-    if (omtu)
-        *omtu = 48;
+        /* Setting defaults in case of error */
+        if (imtu) *imtu = 48;
+        if (omtu) *omtu = 48;
+    } else {
+        if (imtu) *imtu = sco_opt.mtu;
+        if (omtu) *omtu = sco_opt.mtu;
+    }
 
     return sock;