Bluetooth: Send HCI Reset command by default on device initialization

The Bluetooth subsystem was not using the HCI Reset command when doing
device initialization. The Bluetooth 1.0b specification was ambiguous
on how the device firmware was suppose to handle it. Almost every device
was triggering a transport reset at the same time. In case of USB this
ended up in disconnects from the bus.

All modern Bluetooth dongles handle this perfectly fine and a lot of
them actually require that HCI Reset is sent. If not then they are
either stuck in their HID Proxy mode or their internal structures for
inquiry and paging are not correctly setup.

To handle old and new devices smoothly the Bluetooth subsystem contains
a quirk to force the HCI Reset on initialization. However maintaining
such a quirk becomes more and more complicated. This patch turns the
logic around and lets the old devices disable the HCI Reset command.

The only device where the HCI_QUIRK_NO_RESET is still needed are the
original Digianswer devices and dongles with an early CSR firmware.

CSR reported that they fixed this for version 12 firmware. The last
official release of version 11 firmware is build ID 115. The first
version 12 candidate was build ID 117.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/bluetooth/bpa10x.c b/drivers/bluetooth/bpa10x.c
index b936d8ce272..4f0a57236d2 100644
--- a/drivers/bluetooth/bpa10x.c
+++ b/drivers/bluetooth/bpa10x.c
@@ -489,6 +489,8 @@ static int bpa10x_probe(struct usb_interface *intf, const struct usb_device_id *
 
 	hdev->owner = THIS_MODULE;
 
+	set_bit(HCI_QUIRK_NO_RESET, &hdev->quirks);
+
 	err = hci_register_dev(hdev);
 	if (err < 0) {
 		hci_free_dev(hdev);