Subject: [PATCH v2 2/4] Bluetooth: add quirk for broken address properties

From: Johan Hovold <[email-masked]>
Date: Mon, 18 Mar 2024 12:08:53 +0100

Some 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 devicetree 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 bootloaders have
been providing the address in big-endian order instead.

Add a new quirk that can be used to mark deprecated compatible strings
that expect such broken devicetree properties and use it to reverse the
address when parsing the property so that the underlying driver bug can
be fixed.

Fixes: 5c0a1001c8be ("Bluetooth: hci_qca: Add helper to set device address")
Cc: [email-masked]      # 5.1
Signed-off-by: Johan Hovold <[email-masked]>
---
 include/net/bluetooth/hci.h | 10 ++++++++++
 net/bluetooth/hci_sync.c    |  5 ++++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index bdee5d649cc6..556cffed5698 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -176,6 +176,16 @@ enum {
 	 */
 	HCI_QUIRK_USE_BDADDR_PROPERTY,
 
+	/* When this quirk is set, the Bluetooth Device Address provided by
+	 * the 'local-bd-address' fwnode property is incorrectly specified in
+	 * big-endian order.
+	 *
+	 * This quirk can be set before hci_register_dev is called or
+	 * during the hdev->setup vendor callback and must only be used for
+	 * deprecated compatible strings.
+	 */
+	HCI_QUIRK_BDADDR_PROPERTY_BROKEN,
+
 	/* When this quirk is set, the duplicate filtering during
 	 * scanning is based on Bluetooth devices addresses. To allow
 	 * RSSI based updates, restart scanning if needed.
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 5716345a26df..283ae8edc1e5 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -3215,7 +3215,10 @@ static void hci_dev_get_bd_addr_from_property(struct hci_dev *hdev)
 	if (ret < 0 || !bacmp(&ba, BDADDR_ANY))
 		return;
 
-	bacpy(&hdev->public_addr, &ba);
+	if (test_bit(HCI_QUIRK_BDADDR_PROPERTY_BROKEN, &hdev->quirks))
+		baswap(&hdev->public_addr, &ba);
+	else
+		bacpy(&hdev->public_addr, &ba);
 }
 
 struct hci_init_stage {
-- 
2.43.2