[PATCH 1/2] Bluetooth: Add quirk for reading BD_ADDR from fwnode property

[Matthias Kaehlcke <mka@chromium.org>]

Add HCI_QUIRK_USE_BDADDR_PROPERTY to allow controllers to retrieve
the public Bluetooth address from the firmware node property
'local-bd-address'. If quirk is set and the property does not exist
or is invalid the controller is marked as unconfigured.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
---
hci_dev_get_bd_addr_from_property() currently assumes that the
firmware node with 'local-bd-address' is from hdev->dev.parent, not
sure if this universally true. However if it is true for existing
device that might use this interface we can assume this for now
(unless there is a clear solution now), and cross the bridge of
finding an alternative when we actually encounter the situation.
One option could be to look for the first parent that has a fwnode.
---
 include/net/bluetooth/hci.h | 12 +++++++++++
 net/bluetooth/hci_core.c    | 42 +++++++++++++++++++++++++++++++++++++
 net/bluetooth/mgmt.c        |  6 ++++--
 3 files changed, 58 insertions(+), 2 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index cdd9f1fe7cfa..a5d748099752 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -158,6 +158,18 @@ enum {
 	 */
 	HCI_QUIRK_INVALID_BDADDR,
 
+	/* When this quirk is set, the public Bluetooth address
+	 * initially reported by HCI Read BD Address command
+	 * is considered invalid. The public BD Address can be
+	 * specified in the fwnode property 'local-bd-address'.
+	 * If this property does not exist or is invalid controller
+	 * configuration is required before this device can be used.
+	 *
+	 * This quirk can be set before hci_register_dev is called or
+	 * during the hdev->setup vendor callback.
+	 */
+	HCI_QUIRK_USE_BDADDR_PROPERTY,
+
 	/* 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_core.c b/net/bluetooth/hci_core.c
index 74b29c7d841c..97214262c4fb 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -30,6 +30,7 @@
 #include <linux/rfkill.h>
 #include <linux/debugfs.h>
 #include <linux/crypto.h>
+#include <linux/property.h>
 #include <asm/unaligned.h>
 
 #include <net/bluetooth/bluetooth.h>
@@ -1355,9 +1356,40 @@ int hci_inquiry(void __user *arg)
 	return err;
 }
 
+/**
+ * hci_dev_get_bd_addr_from_property - Get the Bluetooth Device Address
+ *				       (BD_ADDR) for a HCI device from
+ *				       a firmware node property.
+ * @hdev:	The HCI device
+ *
+ * Search the firmware node for 'local-bd-address'.
+ *
+ * All-zero BD addresses are rejected, because those could be properties
+ * that exist in the firmware tables, but were not updated by the firmware. For
+ * example, the DTS could define 'local-bd-address', with zero BD addresses.
+ */
+static int hci_dev_get_bd_addr_from_property(struct hci_dev *hdev)
+{
+	struct fwnode_handle *fwnode = dev_fwnode(hdev->dev.parent);
+	bdaddr_t ba;
+	int ret;
+
+	ret = fwnode_property_read_u8_array(fwnode, "local-bd-address",
+					    (u8 *)&ba, sizeof(ba));
+	if (ret < 0)
+		return ret;
+	if (!bacmp(&ba, BDADDR_ANY))
+		return -ENODATA;
+
+	hdev->public_addr = ba;
+
+	return 0;
+}
+
 static int hci_dev_do_open(struct hci_dev *hdev)
 {
 	int ret = 0;
+	bool bd_addr_set = false;
 
 	BT_DBG("%s %p", hdev->name, hdev);
 
@@ -1422,6 +1454,16 @@ static int hci_dev_do_open(struct hci_dev *hdev)
 		if (hdev->setup)
 			ret = hdev->setup(hdev);
 
+		if (test_bit(HCI_QUIRK_USE_BDADDR_PROPERTY, &hdev->quirks)) {
+			if (!hci_dev_get_bd_addr_from_property(hdev))
+				if (hdev->set_bdaddr &&
+				    !hdev->set_bdaddr(hdev, &hdev->public_addr))
+					bd_addr_set = true;
+
+			if (!bd_addr_set)
+				hci_dev_set_flag(hdev, HCI_UNCONFIGURED);
+		}
+
 		/* The transport driver can set these quirks before
 		 * creating the HCI device or in its setup callback.
 		 *
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 3bdc8f3ca259..3d9edb752403 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -551,7 +551,8 @@ static bool is_configured(struct hci_dev *hdev)
 	    !hci_dev_test_flag(hdev, HCI_EXT_CONFIGURED))
 		return false;
 
-	if (test_bit(HCI_QUIRK_INVALID_BDADDR, &hdev->quirks) &&
+	if ((test_bit(HCI_QUIRK_INVALID_BDADDR, &hdev->quirks) ||
+	     test_bit(HCI_QUIRK_USE_BDADDR_PROPERTY, &hdev->quirks)) &&
 	    !bacmp(&hdev->public_addr, BDADDR_ANY))
 		return false;
 
@@ -566,7 +567,8 @@ static __le32 get_missing_options(struct hci_dev *hdev)
 	    !hci_dev_test_flag(hdev, HCI_EXT_CONFIGURED))
 		options |= MGMT_OPTION_EXTERNAL_CONFIG;
 
-	if (test_bit(HCI_QUIRK_INVALID_BDADDR, &hdev->quirks) &&
+	if ((test_bit(HCI_QUIRK_INVALID_BDADDR, &hdev->quirks) ||
+	     test_bit(HCI_QUIRK_USE_BDADDR_PROPERTY, &hdev->quirks)) &&
 	    !bacmp(&hdev->public_addr, BDADDR_ANY))
 		options |= MGMT_OPTION_PUBLIC_ADDRESS;
 
-- 
2.19.1.568.g152ad8e336-goog