[PATCH v3 4/5] Bluetooth: qca: add workaround for broken address properties

Johan Hovold
2024-03-19T15:29:53Z

Due to a long-standing bug in the Qualcomm Bluetooth driver, the device
address has so far been reversed when configuring non-ROME controllers.
This, in turn, has led to one vendor reversing the address that the boot
firmware provides using the 'local-bd-address' devicetree property.

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>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
drivers/bluetooth/hci_qca.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index f989c05f8177..c73481c57741 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -225,6 +225,7 @@ struct qca_serdev {
struct qca_power *bt_power;
u32 init_speed;
u32 oper_speed;
+ bool bdaddr_property_broken;
const char *firmware_name;
};

@@ -1842,6 +1843,7 @@ static int qca_setup(struct hci_uart *hu)
const char *firmware_name = qca_get_firmware_name(hu);
int ret;
struct qca_btsoc_version ver;
+ struct qca_serdev *qcadev;
const char *soc_name;

ret = qca_check_speeds(hu);
@@ -1904,6 +1906,11 @@ static int qca_setup(struct hci_uart *hu)
case QCA_WCN6855:
case QCA_WCN7850:
set_bit(HCI_QUIRK_USE_BDADDR_PROPERTY, &hdev->quirks);
+
+ qcadev = serdev_device_get_drvdata(hu->serdev);
+ if (qcadev->bdaddr_property_broken)
+ set_bit(HCI_QUIRK_BDADDR_PROPERTY_BROKEN, &hdev->quirks);
+
hci_set_aosp_capable(hdev);

ret = qca_read_soc_version(hdev, &ver, soc_type);
@@ -2284,6 +2291,9 @@ static int qca_serdev_probe(struct serdev_device *serdev)
if (!qcadev->oper_speed)
BT_DBG("UART will pick default operating speed");

+ qcadev->bdaddr_property_broken = device_property_read_bool(&serdev->dev,
+ "qcom,local-bd-address-broken");
+
if (data)
qcadev->btsoc_type = data->soc_type;
else
--
2.43.2