Re: [PATCH bluetooth] Bluetooth: qca: Fix the WCN3950 NVM baud rate offset

From: Bartosz Golaszewski

Date: Thu Oct 22 2026 - 04:37:04 EST


On Wed, 21 Oct 2026 21:51:12 +0200, Michael McAllister
<me@xxxxxxxxxxxxxxxxxxxxx> said:
> WCN3950 uses the HCI transport tag layout that stores the UART baud rate
> at byte 1, like WCN3991. However, QCA_WCN3950 precedes QCA_WCN3991 in
> qca_btsoc_type, so qca_tlv_check_data() writes the baud rate to byte 2
> instead.
>
> On a Motorola Moto G10 with WCN3950 and cmnv12.bin, configuring a 3 Mbps
> UART therefore leaves the NVM baud rate at its default 3.2 Mbps and
> overwrites the following byte. Firmware download completes, but the
> subsequent HCI_RESET times out and Bluetooth initialization fails.
>
> Include WCN3950 in the byte-1 case so the NVM baud rate matches the host
> UART without altering the following transport parameter.
>
> Fixes: d5712c511cb3 ("Bluetooth: qca: add WCN3950 support")
> Cc: stable@xxxxxxxxxxxxxxx
> Assisted-by: LLM

This tag is now gone, you don't have to add it.

> Signed-off-by: Michael McAllister <me@xxxxxxxxxxxxxxxxxxxxx>
> ---

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxxxxxxxx>