This is a note to let you know that I've just added the patch titled
Bluetooth: hci_event: Fix setting of unicast qos interval
to the 6.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bluetooth-hci_event-fix-setting-of-unicast-qos-inter.patch
and it can be found in the queue-6.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f2d0e11b8ecfaf66c1642fc9f1b0f5976fc2956b
Author: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Date: Thu Jun 6 12:04:30 2024 -0400
Bluetooth: hci_event: Fix setting of unicast qos interval
[ Upstream commit ac65ecccae802417ce42e857defacad60e4b8329 ]
qos->ucast interval reffers to the SDU interval, and should not
be set to the interval value reported by the LE CIS Established
event since the latter reffers to the ISO interval. These two
interval are not the same thing:
BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 6, Part G
Isochronous interval:
The time between two consecutive BIS or CIS events (designated
ISO_Interval in the Link Layer)
SDU interval:
The nominal time between two consecutive SDUs that are sent or
received by the upper layer.
So this instead uses the following formula from the spec to calculate
the resulting SDU interface:
BLUETOOTH CORE SPECIFICATION Version 5.4 | Vol 6, Part G
page 3075:
Transport_Latency_C_To_P = CIG_Sync_Delay + (FT_C_To_P) ×
ISO_Interval + SDU_Interval_C_To_P
Transport_Latency_P_To_C = CIG_Sync_Delay + (FT_P_To_C) ×
ISO_Interval + SDU_Interval_P_To_C
Link: https://github.com/bluez/bluez/issues/823
Fixes: 2be22f1941d5 ("Bluetooth: hci_event: Fix parsing of CIS Established Event")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 1ed734a7fb313..0b3a76fcfedf5 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -6661,6 +6661,7 @@ static void hci_le_cis_estabilished_evt(struct hci_dev *hdev, void *data,
struct bt_iso_qos *qos;
bool pending = false;
u16 handle = __le16_to_cpu(ev->handle);
+ u32 c_sdu_interval, p_sdu_interval;
bt_dev_dbg(hdev, "status 0x%2.2x", ev->status);
@@ -6685,12 +6686,25 @@ static void hci_le_cis_estabilished_evt(struct hci_dev *hdev, void *data,
pending = test_and_clear_bit(HCI_CONN_CREATE_CIS, &conn->flags);
- /* Convert ISO Interval (1.25 ms slots) to SDU Interval (us) */
- qos->ucast.in.interval = le16_to_cpu(ev->interval) * 1250;
- qos->ucast.out.interval = qos->ucast.in.interval;
+ /* BLUETOOTH CORE SPECIFICATION Version 5.4 | Vol 6, Part G
+ * page 3075:
+ * Transport_Latency_C_To_P = CIG_Sync_Delay + (FT_C_To_P) ×
+ * ISO_Interval + SDU_Interval_C_To_P
+ * ...
+ * SDU_Interval = (CIG_Sync_Delay + (FT) x ISO_Interval) -
+ * Transport_Latency
+ */
+ c_sdu_interval = (get_unaligned_le24(ev->cig_sync_delay) +
+ (ev->c_ft * le16_to_cpu(ev->interval) * 1250)) -
+ get_unaligned_le24(ev->c_latency);
+ p_sdu_interval = (get_unaligned_le24(ev->cig_sync_delay) +
+ (ev->p_ft * le16_to_cpu(ev->interval) * 1250)) -
+ get_unaligned_le24(ev->p_latency);
switch (conn->role) {
case HCI_ROLE_SLAVE:
+ qos->ucast.in.interval = c_sdu_interval;
+ qos->ucast.out.interval = p_sdu_interval;
/* Convert Transport Latency (us) to Latency (msec) */
qos->ucast.in.latency =
DIV_ROUND_CLOSEST(get_unaligned_le24(ev->c_latency),
@@ -6704,6 +6718,8 @@ static void hci_le_cis_estabilished_evt(struct hci_dev *hdev, void *data,
qos->ucast.out.phy = ev->p_phy;
break;
case HCI_ROLE_MASTER:
+ qos->ucast.in.interval = p_sdu_interval;
+ qos->ucast.out.interval = c_sdu_interval;
/* Convert Transport Latency (us) to Latency (msec) */
qos->ucast.out.latency =
DIV_ROUND_CLOSEST(get_unaligned_le24(ev->c_latency),
