[PATCH v4 3/3] Bluetooth: btqcomsmd: retieve BD address from DT

[Loic Poulain <loic.poulain-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>]

Retrieve BD address from the DT local-bd-address property.
This address must be unique and is usually added in the DT
by the bootloader which has access to the provisioned data.

Signed-off-by: Loic Poulain <loic.poulain-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
---
 v2: Set device as unconfigured if default address detected
     Add warning if BD addr retrieved from DT
 v3: if no addr retrieved from DT, unconditionally set
     the invalid BD addr flag.
     swap and set bdaddr in the platform probe
 v4: Add dt-bindings documentation
     split patch in two parts (setup, dt prop)
     use local-bd-address name instead of local-mac-address

 drivers/bluetooth/btqcomsmd.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/bluetooth/btqcomsmd.c b/drivers/bluetooth/btqcomsmd.c
index c70fae75c4ad..08a83cb30af6 100644
--- a/drivers/bluetooth/btqcomsmd.c
+++ b/drivers/bluetooth/btqcomsmd.c
@@ -15,6 +15,8 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/rpmsg.h>
+#include <linux/of.h>
+
 #include <linux/soc/qcom/wcnss_ctrl.h>
 #include <linux/platform_device.h>
 
@@ -126,6 +128,7 @@ static int btqcomsmd_setup(struct hci_dev *hdev)
 
 static int btqcomsmd_probe(struct platform_device *pdev)
 {
+	const bdaddr_t *local_bd_addr;
 	struct btqcomsmd *btq;
 	struct hci_dev *hdev;
 	void *wcnss;
@@ -147,6 +150,18 @@ static int btqcomsmd_probe(struct platform_device *pdev)
 	if (IS_ERR(btq->cmd_channel))
 		return PTR_ERR(btq->cmd_channel);
 
+	/* The local-bd-address DT property is usually injected by the
+	 * bootloader which has access to the allocated BD address.
+	 */
+	local_bd_addr = of_get_property(pdev->dev.of_node, "local-mac-address",
+					&ret);
+	if (local_bd_addr && ret == sizeof(bdaddr_t)) {
+		/* local-bd-address stored with most significant byte first */
+		baswap(&btq->bdaddr, local_bd_addr);
+		BT_INFO("BD address %pMR retrieved from device-tree",
+			&btq->bdaddr);
+	}
+
 	hdev = hci_alloc_dev();
 	if (!hdev)
 		return -ENOMEM;
-- 
2.13.0