This is a note to let you know that I've just added the patch titled
Bluetooth: btusb: Fix not handling ZPL/short-transfer
to the 4.19-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-btusb-fix-not-handling-zpl-short-transfer.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6cf6a3ef604bda727e98bc4bef9646ab35d22f3d
Author: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Date: Mon Sep 9 16:51:52 2024 -0400
Bluetooth: btusb: Fix not handling ZPL/short-transfer
[ Upstream commit 7b05933340f4490ef5b09e84d644d12484b05fdf ]
Requesting transfers of the exact same size of wMaxPacketSize may result
in ZPL/short-transfer since the USB stack cannot handle it as we are
limiting the buffer size to be the same as wMaxPacketSize.
Also, in terms of throughput this change has the same effect to
interrupt endpoint as 290ba200815f "Bluetooth: Improve USB driver throughput
by increasing the frame size" had for the bulk endpoint, so users of the
advertisement bearer (e.g. BT Mesh) may benefit from this change.
Fixes: 5e23b923da03 ("[Bluetooth] Add generic driver for Bluetooth USB devices")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Tested-by: Kiran K <kiran.k@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index b6eb48e44e6b1..c7a1ec57256b4 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -743,7 +743,10 @@ static int btusb_submit_intr_urb(struct hci_dev *hdev, gfp_t mem_flags)
if (!urb)
return -ENOMEM;
- size = le16_to_cpu(data->intr_ep->wMaxPacketSize);
+ /* Use maximum HCI Event size so the USB stack handles
+ * ZPL/short-transfer automatically.
+ */
+ size = HCI_MAX_EVENT_SIZE;
buf = kmalloc(size, mem_flags);
if (!buf) {
