Bluetooth: btusb: Add protocol support for MediaTek USB devices

From: Sean Wang <[email protected]>

v7:
* rebase to latest code base.

v6:
* fix drivers/bluetooth/btusb.c:2683:2-3: Unneeded semicolon based reported by [1]
* update power-on sequence with adding neccesary tci sleep comand to set up low-power environmnet and a delay to wait the device to be stable.
* sort variables declarations in reverse xmas order.

[1]
http://lists.infradead.org/pipermail/linux-mediatek/2019-January/017017.html

v5:
* rebase to latest code base.
* change the subject prefix.
* change the place the firmware located at.

v4:
* use new BTUSB_TX_WAIT_VND_EVT instead of BTMTKUSB_TX_WAIT_VND_EVT to avoid definition conflict and to fix bulk data transfer fails.
* use the bluetooth-next as the base

v3:
add fixes and enhancements based on [1]
* reuse flags and evt_skb btusb already had
* add ctrl_anchor and the corresponding handling
* apply mtk specific recv function
* add more comments explaining wmt ctrl urbs behavior.

[1]
http://lists.infradead.org/pipermail/linux-mediatek/2018-August/014724.html

v2:

add fixes and enhancements based on [1]
* include /sys/kernel/debug/usb/devices portion in the commit message.
* turn default into n for config BT_HCIBTUSB_MTK in Kconfig
* only add MediaTek support to btusb.c
* drop cmd_sync callback usage
* use __hci_cmd_send to send WMT commands
* add wait event handling similar to what is being done in btmtkuart.c
* submit a control IN URB similar to interrupt IN URB on demand for the WMT commands during setup
* add cosmetic changes

[1]
http://lists.infradead.org/pipermail/linux-mediatek/2018-August/014650.html
http://lists.infradead.org/pipermail/linux-mediatek/2018-August/014656.html

v1:

This adds the support of enabling MT7668U and MT7663U Bluetooth function running on the top of btusb driver. The patch also adds a newly created file mtkbt.c able to be reused independently from the transport type such as UART, USB and SDIO.

Sean Wang (2):
Bluetooth: btusb: Add protocol support for MediaTek MT7668U USB
devices
Bluetooth: btusb: Add protocol support for MediaTek MT7663U USB
devices

 drivers/bluetooth/Kconfig |  11 +
 drivers/bluetooth/btusb.c | 581 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 592 insertions(+)

2.17.1