[PATCH v2] Bluetooth: btusb: USB alternate setting 1 for WBS

[hildawu at realtek.com]

From: Hilda Wu <hildawu at realtek.com>

RTL8822CE supports transparent WBS to apply USB alternate setting 1.
Add a flag to the device match data to apply alternate setting 1 which
meet the transfer speed for WBS support.

Signed-off-by: Hilda Wu <hildawu at realtek.com>
---
Changes in v2:
- More descriptive commit log and short description.
- Use BTUSB_USE_ALT1_FOR_WBS replace BTUSB_WBS_ALT1 for descriptive name.
- Move alternate setting 1 check into the btusb_probe() function and adjust position of data->isoc for alternate setting check.
---
---
 drivers/bluetooth/btusb.c | 34 ++++++++++++++++++++--------------
 1 file changed, 20 insertions(+), 14 deletions(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index c7cc8e594166..e4a12c58501e 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -453,6 +453,7 @@ static const struct dmi_system_id btusb_needs_reset_resume_table[] = {
 #define BTUSB_HW_RESET_ACTIVE	12
 #define BTUSB_TX_WAIT_VND_EVT	13
 #define BTUSB_WAKEUP_DISABLE	14
+#define BTUSB_USE_ALT1_FOR_WBS	15
 
 struct btusb_data {
 	struct hci_dev       *hdev;
@@ -1666,14 +1667,15 @@ static void btusb_work(struct work_struct *work)
 				new_alts = data->sco_num;
 			}
 		} else if (data->air_mode == HCI_NOTIFY_ENABLE_SCO_TRANSP) {
-
-			data->usb_alt6_packet_flow = true;
-
 			/* Check if Alt 6 is supported for Transparent audio */
-			if (btusb_find_altsetting(data, 6))
+			if (btusb_find_altsetting(data, 6)) {
+				data->usb_alt6_packet_flow = true;
 				new_alts = 6;
-			else
+			} else if (test_bit(BTUSB_USE_ALT1_FOR_WBS, &data->flags)) {
+				new_alts = 1;
+			} else {
 				bt_dev_err(hdev, "Device does not support ALT setting 6");
+			}
 		}
 
 		if (btusb_switch_alt_setting(hdev, new_alts) < 0)
@@ -3954,6 +3956,15 @@ static int btusb_probe(struct usb_interface *intf,
 		btusb_check_needs_reset_resume(intf);
 	}
 
+	if (id->driver_info & BTUSB_AMP) {
+		/* AMP controllers do not support SCO packets */
+		data->isoc = NULL;
+	} else {
+		/* Interface orders are hardcoded in the specification */
+		data->isoc = usb_ifnum_to_if(data->udev, ifnum_base + 1);
+		data->isoc_ifnum = ifnum_base + 1;
+	}
+
 	if (IS_ENABLED(CONFIG_BT_HCIBTUSB_RTL) &&
 	    (id->driver_info & BTUSB_REALTEK)) {
 		hdev->setup = btrtl_setup_realtek;
@@ -3965,21 +3976,16 @@ static int btusb_probe(struct usb_interface *intf,
 		 * (DEVICE_REMOTE_WAKEUP)
 		 */
 		set_bit(BTUSB_WAKEUP_DISABLE, &data->flags);
+		if (btusb_find_altsetting(data, 1))
+			set_bit(BTUSB_USE_ALT1_FOR_WBS, &data->flags);
+		else
+			bt_dev_err(hdev, "Device does not support ALT setting 1");
 
 		err = usb_autopm_get_interface(intf);
 		if (err < 0)
 			goto out_free_dev;
 	}
 
-	if (id->driver_info & BTUSB_AMP) {
-		/* AMP controllers do not support SCO packets */
-		data->isoc = NULL;
-	} else {
-		/* Interface orders are hardcoded in the specification */
-		data->isoc = usb_ifnum_to_if(data->udev, ifnum_base + 1);
-		data->isoc_ifnum = ifnum_base + 1;
-	}
-
 	if (!reset)
 		set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
 
-- 
2.17.1