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>

diff --git a/drivers/bluetooth/btqca.c b/drivers/bluetooth/btqca.c
index b40b32f..19cfc34 100644 (file)
--- a/drivers/bluetooth/btqca.c
+++ b/drivers/bluetooth/btqca.c
@@ -826,11 +826,15 @@ EXPORT_SYMBOL_GPL(qca_uart_setup);
 
 int qca_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
 {
+       bdaddr_t bdaddr_swapped;
        struct sk_buff *skb;
        int err;
 
-       skb = __hci_cmd_sync_ev(hdev, EDL_WRITE_BD_ADDR_OPCODE, 6, bdaddr,
-                               HCI_EV_VENDOR, HCI_INIT_TIMEOUT);
+       baswap(&bdaddr_swapped, bdaddr);
+
+       skb = __hci_cmd_sync_ev(hdev, EDL_WRITE_BD_ADDR_OPCODE, 6,
+                               &bdaddr_swapped, HCI_EV_VENDOR,
+                               HCI_INIT_TIMEOUT);
        if (IS_ERR(skb)) {
                err = PTR_ERR(skb);
                bt_dev_err(hdev, "QCA Change address cmd failed (%d)", err);

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index 4ecbcb1..ecbc52e 100644 (file)
--- 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 @@ retry:
        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