Bluetooth: qca: fix device-address endianness
authorJohan Hovold <johan+linaro@kernel.org>
Wed, 20 Mar 2024 07:55:54 +0000 (08:55 +0100)
committerLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Fri, 29 Mar 2024 13:48:37 +0000 (09:48 -0400)
commit77f45cca8bc55d00520a192f5a7715133591c83e
tree0f43934c388004ffa1a88c192f8c58c34f3f07e9
parent39646f29b100566451d37abc4cc8cdd583756dfe
Bluetooth: qca: fix device-address endianness

The WCN6855 firmware on the Lenovo ThinkPad X13s expects the Bluetooth
device address in big-endian order when setting it using the
EDL_WRITE_BD_ADDR_OPCODE command.

Presumably, this is the case for all non-ROME devices which all use the
EDL_WRITE_BD_ADDR_OPCODE command for this (unlike the ROME devices which
use a different command and expect the address in little-endian order).

Reverse the little-endian address before setting it to make sure that
the address can be configured using tools like btmgmt or using the
'local-bd-address' devicetree property.

Note that this can potentially break systems with boot firmware which
has started relying on the broken behaviour and is incorrectly passing
the address via devicetree in big-endian order.

The only device affected by this should be the WCN3991 used in some
Chromebooks. As ChromeOS updates the kernel and devicetree in lockstep,
the new 'qcom,local-bd-address-broken' property can be used to determine
if the firmware is buggy so that the underlying driver bug can be fixed
without breaking backwards compatibility.

Set the HCI_QUIRK_BDADDR_PROPERTY_BROKEN quirk for such platforms so
that the address is reversed when parsing the address property.

Fixes: 5c0a1001c8be ("Bluetooth: hci_qca: Add helper to set device address")
Cc: stable@vger.kernel.org # 5.1
Cc: Balakrishna Godavarthi <quic_bgodavar@quicinc.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Nikita Travkin <nikita@trvn.ru> # sc7180
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
drivers/bluetooth/btqca.c
drivers/bluetooth/hci_qca.c