[PATCH] Bluetooth: Partial support for Actions Semi ATS2851 based devices

[Raul Cheleguini <raul.cheleguini@xxxxxxxxx>]

This change enables support to device initialization and to scan
process, by adding two new quirks for the following advertised but
unsupported commands: "Set Random Private Address Timeout" and
"Extended Create Connection".

It offers partial device support: controller initialization and scan.
The pairing process still needs work.

At the moment there is little to none available documentation about the
ATS2851 and its based USB dongles. It is known that it works in other
systems via generic drivers, and this is one step towards have it working
in Linux.

Signed-off-by: Raul Cheleguini <raul.cheleguini@xxxxxxxxx>
---
 drivers/bluetooth/btusb.c   |  2 ++
 include/net/bluetooth/hci.h | 14 ++++++++++++++
 net/bluetooth/hci_sync.c    | 13 +++++++++++--
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 7382b021f3df..7bba19061277 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -4106,6 +4106,8 @@ static int btusb_probe(struct usb_interface *intf,
 		set_bit(HCI_QUIRK_BROKEN_ERR_DATA_REPORTING, &hdev->quirks);
 		set_bit(HCI_QUIRK_BROKEN_READ_TRANSMIT_POWER, &hdev->quirks);
 		set_bit(HCI_QUIRK_BROKEN_EXT_SCAN, &hdev->quirks);
+		set_bit(HCI_QUIRK_BROKEN_SET_RPA_TIMEOUT, &hdev->quirks);
+		set_bit(HCI_QUIRK_BROKEN_EXT_CREATE_CONN, &hdev->quirks);
 	}
 
 	if (!reset)
diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 997107bfc0b1..3ff1681fd2b8 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -301,6 +301,20 @@ enum {
 	 * don't actually support features declared there.
 	 */
 	HCI_QUIRK_BROKEN_LOCAL_EXT_FEATURES_PAGE_2,
+
+	/*
+	 * When this quirk is set, the HCI_OP_LE_SET_RPA_TIMEOUT command is
+	 * disabled. This is required for the Actions Semiconductor ATS2851
+	 * controller, which erroneously claim to support it.
+	 */
+	HCI_QUIRK_BROKEN_SET_RPA_TIMEOUT,
+
+	/*
+	 * When this quirk is set, the HCI_OP_LE_EXT_CREATE_CONN command is
+	 * disabled. This is required for the Actions Semiconductor ATS2851
+	 * controller, which erroneously claim to support it.
+	 */
+	HCI_QUIRK_BROKEN_EXT_CREATE_CONN,
 };
 
 /* HCI device flags */
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 8e5fe73873a8..9b2a0d6d6c1a 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -4090,9 +4090,11 @@ static int hci_le_set_rpa_timeout_sync(struct hci_dev *hdev)
 {
 	__le16 timeout = cpu_to_le16(hdev->rpa_timeout);
 
-	if (!(hdev->commands[35] & 0x04))
+	if (!(hdev->commands[35] & 0x04) ||
+	    test_bit(HCI_QUIRK_BROKEN_SET_RPA_TIMEOUT, &hdev->quirks))
 		return 0;
 
+
 	return __hci_cmd_sync_status(hdev, HCI_OP_LE_SET_RPA_TIMEOUT,
 				     sizeof(timeout), &timeout,
 				     HCI_CMD_TIMEOUT);
@@ -4530,6 +4532,12 @@ static const struct {
 			 "HCI Set Event Filter command not supported."),
 	HCI_QUIRK_BROKEN(ENHANCED_SETUP_SYNC_CONN,
 			 "HCI Enhanced Setup Synchronous Connection command is "
+			  "advertised, but not supported."),
+	HCI_QUIRK_BROKEN(SET_RPA_TIMEOUT,
+			 "HCI LE Set Random Private Address Timeout command is "
+			 "advertised, but not supported."),
+	HCI_QUIRK_BROKEN(EXT_CREATE_CONN,
+			 "HCI LE Extended Create Connection command is "
 			 "advertised, but not supported.")
 };
 
@@ -6067,7 +6075,8 @@ int hci_le_create_conn_sync(struct hci_dev *hdev, struct hci_conn *conn)
 	if (err)
 		goto done;
 
-	if (use_ext_conn(hdev)) {
+	if (use_ext_conn(hdev) &&
+	    !test_bit(HCI_QUIRK_BROKEN_EXT_CREATE_CONN, &hdev->quirks)) {
 		err = hci_le_ext_create_conn_sync(hdev, conn, own_addr_type);
 		goto done;
 	}
-- 
2.39.2