[v4,0/4] Bluetooth: qca: fix device-address endianness

The Qualcomm Bluetooth driver is configuring the device address in
reverse order for none-ROME devices, which breaks user space tools like
btmgmt and the 'local-bd-address' devicetree property.

As these Qualcomm controllers lack persistent storage for the device
address, boot firmware can use the 'local-bd-address' devicetree
property to provide a valid address. The property should specify the
address in little endian order but instead some boot firmware has been
reversing the address to match the buggy Qualcomm driver.

This specifically affects some Chromebook devices for which we now need
to maintain compatibility with the current boot firmware. As ChromeOS
updates the kernel and devicetree in lockstep, this can be done by
adding a new 'qcom,local-bd-address-broken' property that can be used to
determine if the firmware passes the address in the wrong byte order.
[1][2]

Note that this series depends on the following revert:

	https://lore.kernel.org/lkml/20240314084412.1127-1-johan+linaro@kernel.org/

Also note that the devicetree patch (patch 2/4) is expected to be merged
through the Qualcomm SoC tree once the other three patches have been
picked up by the Bluetooth maintainers.

An alternative would be if Bjorn could ack the DT patch so that
everything can go in through the Bluetooth tree.

Johan


[1] https://lore.kernel.org/lkml/ZcuWQkmYK4Ax9kam@google.com/
[2] https://lore.kernel.org/lkml/CAD=FV=WCzrh926mkiyBnKRG_+KGuOkGN6v0DgPiXhQCD3PSQ9w@mail.gmail.com/


Changes in v4
 - add the missing type for the new vendor property to the binding
 - move the Trogdor DT patch after the binding patch and combine the
   endianness fix and Chromium workaround to avoid having any point in
   the series where the address is reversed on those platforms as
   requested by Doug

Changes in v3
 - add a 'qcom,local-bd-address-broken' property instead of deprecating
   the current WCN3991 binding
 - mark the bluetooth address on SC7180 Trogdor Chromebooks as broken

Changes in v2
 - add quirk to handle deprecated devicetree compatibles that expect
   broken address properties
 - deprecate 'qcom,wcn3991-bt' and mark it as broken


Johan Hovold (4):
  dt-bindings: bluetooth: add 'qcom,local-bd-address-broken'
  arm64: dts: qcom: sc7180-trogdor: mark bluetooth address as broken
  Bluetooth: add quirk for broken address properties
  Bluetooth: qca: fix device-address endianness

 .../bindings/net/bluetooth/qualcomm-bluetooth.yaml     |  4 ++++
 arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi           |  2 ++
 drivers/bluetooth/btqca.c                              |  8 ++++++--
 drivers/bluetooth/hci_qca.c                            | 10 ++++++++++
 include/net/bluetooth/hci.h                            |  9 +++++++++
 net/bluetooth/hci_sync.c                               |  5 ++++-
 6 files changed, 35 insertions(+), 3 deletions(-)

On Wed, Mar 20, 2024 at 08:55:52AM +0100, Johan Hovold wrote:
> Several Qualcomm Bluetooth controllers lack persistent storage for the
> device address and instead one can be provided by the boot firmware
> using the 'local-bd-address' devicetree property.
> 
> The Bluetooth bindings clearly states that the address should be
> specified in little-endian order, but due to a long-standing bug in the
> Qualcomm driver which reversed the address some boot firmware has been
> providing the address in big-endian order instead.
> 
> The boot firmware in SC7180 Trogdor Chromebooks is known to be affected
> so mark the 'local-bd-address' property as broken to maintain backwards
> compatibility with older firmware when fixing the underlying driver bug.
> 
> Note that ChromeOS always updates the kernel and devicetree in lockstep
> so that there is no need to handle backwards compatibility with older
> devicetrees.
> 
> Fixes: 7ec3e67307f8 ("arm64: dts: qcom: sc7180-trogdor: add initial trogdor and lazor dt")
> Cc: stable@vger.kernel.org      # 5.10
> Cc: Rob Clark <robdclark@chromium.org>
> Reviewed-by: Douglas Anderson <dianders@chromium.org>
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>

Acked-by: Bjorn Andersson <andersson@kernel.org>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>

Please merge this through the BT tree, together with the other patches.

Regards,
Bjorn

> ---
>  arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> index 46aaeba28604..ebe37678102f 100644
> --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> @@ -943,6 +943,8 @@ bluetooth: bluetooth {
>  		vddrf-supply = <&pp1300_l2c>;
>  		vddch0-supply = <&pp3300_l10c>;
>  		max-speed = <3200000>;
> +
> +		qcom,local-bd-address-broken;
>  	};
>  };
>  
> -- 
> 2.43.2
>

Hello:

This series was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz <luiz.von.dentz@intel.com>:

On Wed, 20 Mar 2024 08:55:50 +0100 you wrote:
> The Qualcomm Bluetooth driver is configuring the device address in
> reverse order for none-ROME devices, which breaks user space tools like
> btmgmt and the 'local-bd-address' devicetree property.
> 
> As these Qualcomm controllers lack persistent storage for the device
> address, boot firmware can use the 'local-bd-address' devicetree
> property to provide a valid address. The property should specify the
> address in little endian order but instead some boot firmware has been
> reversing the address to match the buggy Qualcomm driver.
> 
> [...]

Here is the summary with links:
  - [v4,1/4] dt-bindings: bluetooth: add 'qcom,local-bd-address-broken'
    https://git.kernel.org/bluetooth/bluetooth-next/c/ea56aab91231
  - [v4,2/4] arm64: dts: qcom: sc7180-trogdor: mark bluetooth address as broken
    https://git.kernel.org/bluetooth/bluetooth-next/c/c4406d97b78c
  - [v4,3/4] Bluetooth: add quirk for broken address properties
    https://git.kernel.org/bluetooth/bluetooth-next/c/ddaa064664fe
  - [v4,4/4] Bluetooth: qca: fix device-address endianness
    https://git.kernel.org/bluetooth/bluetooth-next/c/ff2ed85c0122

You are awesome, thank you!