Bluetooth: Add SCO fallback for eSCO connection attempts

When attempting to setup eSCO connections it can happen that some link manager implementations fail to properly negotiate the eSCO parameters and thus fail the eSCO setup. Normally the link manager is responsible for the negotiation of the parameters and actually fallback to SCO if no agreement can be reached. In cases where the link manager is just too stupid, then at least try to establish a SCO link if eSCO fails. For the Bluetooth devices with EDR support this includes handling packet types of EDR basebands. This is particular tricky since for the EDR the logic of enabling/disabling one specific packet type is turned around. This fix contains an extra bitmask to disable eSCO EDR packet when trying to fallback to a SCO connection. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Bluetooth: Add SCO fallback for eSCO connection attempts
When attempting to setup eSCO connections it can happen that some link manager implementations fail to properly negotiate the eSCO parameters and thus fail the eSCO setup. Normally the link manager is responsible for the negotiation of the parameters and actually fallback to SCO if no agreement can be reached. In cases where the link manager is just too stupid, then at least try to establish a SCO link if eSCO fails. For the Bluetooth devices with EDR support this includes handling packet types of EDR basebands. This is particular tricky since for the EDR the logic of enabling/disabling one specific packet type is turned around. This fix contains an extra bitmask to disable eSCO EDR packet when trying to fallback to a SCO connection. Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Marcel Holtmann
1 parent 255c76014a
Showing 3 changed files with 31 additions and 2 deletions Side-by-side Diff
include/net/bluetooth/hci.h
net/bluetooth/hci_conn.c
net/bluetooth/hci_event.c
@@ -133,8 +133,13 @@
 #define ESCO_EV3	0x0008
 #define ESCO_EV4	0x0010
 #define ESCO_EV5	0x0020
+#define ESCO_2EV3	0x0040
+#define ESCO_3EV3	0x0080
+#define ESCO_2EV5	0x0100
+#define ESCO_3EV5	0x0200
  
 #define SCO_ESCO_MASK  (ESCO_HV1 | ESCO_HV2 | ESCO_HV3)
+#define EDR_ESCO_MASK  (ESCO_2EV3 | ESCO_3EV3 | ESCO_2EV5 | ESCO_3EV5)
  
 /* ACL flags */
 #define ACL_CONT		0x01
@@ -176,6 +181,9 @@
 #define LMP_EV5		0x02
  
 #define LMP_SNIFF_SUBR	0x02
+#define LMP_EDR_ESCO_2M	0x20
+#define LMP_EDR_ESCO_3M	0x40
+#define LMP_EDR_3S_ESCO	0x80
  
 #define LMP_SIMPLE_PAIR	0x08
  
@@ -123,6 +123,8 @@
 	conn->state = BT_CONNECT;
 	conn->out = 1;
  
+	conn->attempt++;
+
 	cp.handle   = cpu_to_le16(handle);
 	cp.pkt_type = cpu_to_le16(conn->pkt_type);
  
@@ -139,6 +141,8 @@
 	conn->state = BT_CONNECT;
 	conn->out = 1;
  
+	conn->attempt++;
+
 	cp.handle   = cpu_to_le16(handle);
 	cp.pkt_type = cpu_to_le16(conn->pkt_type);
  
  
@@ -216,12 +220,13 @@
 		break;
 	case SCO_LINK:
 		if (lmp_esco_capable(hdev))
-			conn->pkt_type = hdev->esco_type & SCO_ESCO_MASK;
+			conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
+					(hdev->esco_type & EDR_ESCO_MASK);
 		else
 			conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
 		break;
 	case ESCO_LINK:
-		conn->pkt_type = hdev->esco_type;
+		conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
 		break;
 	}
  
@@ -484,6 +484,15 @@
 	if (hdev->features[4] & LMP_EV5)
 		hdev->esco_type |= (ESCO_EV5);
  
+	if (hdev->features[5] & LMP_EDR_ESCO_2M)
+		hdev->esco_type |= (ESCO_2EV3);
+
+	if (hdev->features[5] & LMP_EDR_ESCO_3M)
+		hdev->esco_type |= (ESCO_3EV3);
+
+	if (hdev->features[5] & LMP_EDR_3S_ESCO)
+		hdev->esco_type |= (ESCO_2EV5 | ESCO_3EV5);
+
 	BT_DBG("%s features 0x%.2x%.2x%.2x%.2x%.2x%.2x%.2x%.2x", hdev->name,
 					hdev->features[0], hdev->features[1],
 					hdev->features[2], hdev->features[3],
@@ -1637,6 +1646,13 @@
 			goto unlock;
  
 		conn->type = SCO_LINK;
+	}
+
+	if (conn->out && ev->status == 0x1c && conn->attempt < 2) {
+		conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
+					(hdev->esco_type & EDR_ESCO_MASK);
+		hci_setup_sync(conn, conn->link->handle);
+		goto unlock;
 	}
  
 	if (!ev->status) {
...	...	@@ -133,8 +133,13 @@
133	133	#define ESCO_EV3 0x0008
134	134	#define ESCO_EV4 0x0010
135	135	#define ESCO_EV5 0x0020
	136	+#define ESCO_2EV3 0x0040
	137	+#define ESCO_3EV3 0x0080
	138	+#define ESCO_2EV5 0x0100
	139	+#define ESCO_3EV5 0x0200
136	140
137	141	#define SCO_ESCO_MASK (ESCO_HV1 \| ESCO_HV2 \| ESCO_HV3)
	142	+#define EDR_ESCO_MASK (ESCO_2EV3 \| ESCO_3EV3 \| ESCO_2EV5 \| ESCO_3EV5)
138	143
139	144	/* ACL flags */
140	145	#define ACL_CONT 0x01
...	...	@@ -176,6 +181,9 @@
176	181	#define LMP_EV5 0x02
177	182
178	183	#define LMP_SNIFF_SUBR 0x02
	184	+#define LMP_EDR_ESCO_2M 0x20
	185	+#define LMP_EDR_ESCO_3M 0x40
	186	+#define LMP_EDR_3S_ESCO 0x80
179	187
180	188	#define LMP_SIMPLE_PAIR 0x08
181	189
...	...	@@ -123,6 +123,8 @@
123	123	conn->state = BT_CONNECT;
124	124	conn->out = 1;
125	125
	126	+ conn->attempt++;
	127	+
126	128	cp.handle = cpu_to_le16(handle);
127	129	cp.pkt_type = cpu_to_le16(conn->pkt_type);
128	130
...	...	@@ -139,6 +141,8 @@
139	141	conn->state = BT_CONNECT;
140	142	conn->out = 1;
141	143
	144	+ conn->attempt++;
	145	+
142	146	cp.handle = cpu_to_le16(handle);
143	147	cp.pkt_type = cpu_to_le16(conn->pkt_type);
144	148
145	149
...	...	@@ -216,12 +220,13 @@
216	220	break;
217	221	case SCO_LINK:
218	222	if (lmp_esco_capable(hdev))
219		- conn->pkt_type = hdev->esco_type & SCO_ESCO_MASK;
	223	+ conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) \|
	224	+ (hdev->esco_type & EDR_ESCO_MASK);
220	225	else
221	226	conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
222	227	break;
223	228	case ESCO_LINK:
224		- conn->pkt_type = hdev->esco_type;
	229	+ conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
225	230	break;
226	231	}
227	232
...	...	@@ -484,6 +484,15 @@
484	484	if (hdev->features[4] & LMP_EV5)
485	485	hdev->esco_type \|= (ESCO_EV5);
486	486
	487	+ if (hdev->features[5] & LMP_EDR_ESCO_2M)
	488	+ hdev->esco_type \|= (ESCO_2EV3);
	489	+
	490	+ if (hdev->features[5] & LMP_EDR_ESCO_3M)
	491	+ hdev->esco_type \|= (ESCO_3EV3);
	492	+
	493	+ if (hdev->features[5] & LMP_EDR_3S_ESCO)
	494	+ hdev->esco_type \|= (ESCO_2EV5 \| ESCO_3EV5);
	495	+
487	496	BT_DBG("%s features 0x%.2x%.2x%.2x%.2x%.2x%.2x%.2x%.2x", hdev->name,
488	497	hdev->features[0], hdev->features[1],
489	498	hdev->features[2], hdev->features[3],
...	...	@@ -1637,6 +1646,13 @@
1637	1646	goto unlock;
1638	1647
1639	1648	conn->type = SCO_LINK;
	1649	+ }
	1650	+
	1651	+ if (conn->out && ev->status == 0x1c && conn->attempt < 2) {
	1652	+ conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) \|
	1653	+ (hdev->esco_type & EDR_ESCO_MASK);
	1654	+ hci_setup_sync(conn, conn->link->handle);
	1655	+ goto unlock;
1640	1656	}
1641	1657
1642	1658	if (!ev->status) {