Return-Path: MIME-Version: 1.0 In-Reply-To: <01000162362879ce-d5906360-2001-4c67-b414-07e116a0ef93-000000@email.amazonses.com> References: <20171117223543.32429-1-martin.blumenstingl@googlemail.com> <20171117223543.32429-7-martin.blumenstingl@googlemail.com> <14831F71-B426-491A-A5B0-7F93533AE78C@holtmann.org> <01000162362879ce-d5906360-2001-4c67-b414-07e116a0ef93-000000@email.amazonses.com> From: Martin Blumenstingl Date: Sun, 18 Mar 2018 23:52:38 +0100 Message-ID: Subject: Re: [RFC v1 6/8] Bluetooth: hci_h5: add support for Realtek UART Bluetooth modules To: Jeremy Cline Cc: Marcel Holtmann , Rob Herring , devicetree , Linux Bluetooth mailing list , linux-serial@vger.kernel.org, Mark Rutland , "Gustavo F. Padovan" , Johan Hedberg , Greg Kroah-Hartman , Jiri Slaby , Johan Hovold , linux-sunxi@googlegroups.com, linux-amlogic@lists.infradead.org, Larry.Finger@lwfinger.net Content-Type: text/plain; charset="UTF-8" List-ID: Hi Jeremy, On Sat, Mar 17, 2018 at 11:50 PM, Jeremy Cline wrote: > Hi Marcel, Martin, > > On 03/16/2018 03:22 PM, Marcel Holtmann wrote: >> Hi Martin, >> >>> Realtek RTL8723BS and RTL8723DS are SDIO wifi chips with an embedded >>> Bluetooth controller which connects to the host via UART. >>> The H5 protocol is used for communication between host and device. >>> >>> The Realtek "rtl8723bs_bt" and "rtl8723ds_bt" userspace Bluetooth UART >>> initialization tools (rtk_hciattach) use the following sequence: >>> 1) send H5 sync pattern (already supported by hci_h5) >>> 2) get LMP version (already supported by btrtl) >>> 3) get ROM version (already supported by btrtl) >>> 4) load the firmware and config for the current chipset (already >>> supported by btrtl) >>> 5) read UART settings from the config blob (already supported by btrtl) >>> 6) send UART settings via a vendor command to the device (which changes >>> the baudrate of the device and enables or disables flow control >>> depending on the config) >>> 7) change the baudrate and flow control settings on the host >>> 8) send the firmware and config blob to the device (already supported by >>> btrtl) >>> >>> This uses the serdev library as well as the existing btrtl driver to >>> initialize the Bluetooth functionality, which consists of: >>> - identifying the device and loading the corresponding firmware and >>> config blobs (steps #2, #3 and #4) >>> - configuring the baudrate and flow control (steps #6 and #7) >>> - uploading the firmware to the device (step #8) >>> >>> Signed-off-by: Martin Blumenstingl >>> --- >>> drivers/bluetooth/Kconfig | 1 + >>> drivers/bluetooth/hci_h5.c | 195 ++++++++++++++++++++++++++++++++++++++++++++- >>> 2 files changed, 195 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig >>> index 60e1c7d6986d..3001f1200c72 100644 >>> --- a/drivers/bluetooth/Kconfig >>> +++ b/drivers/bluetooth/Kconfig >>> @@ -146,6 +146,7 @@ config BT_HCIUART_LL >>> config BT_HCIUART_3WIRE >>> bool "Three-wire UART (H5) protocol support" >>> depends on BT_HCIUART >>> + select BT_RTL if SERIAL_DEV_BUS >>> help >>> The HCI Three-wire UART Transport Layer makes it possible to >>> user the Bluetooth HCI over a serial port interface. The HCI >> >> so I just posted a bt3wire.c driver that is serdev only and written from scratch. On a RPi3 Broadcom chip it kinda works. I think there is a lot of extra work to be done, but this might be a better starting point for Realtek UART devices. > > I picked up the v2 version of this RFC and rebased it to the latest > bluetooth-next and added ACPI support. It also kinda works, but there's > a few problems left to track down and I still haven't looked into > getting rid of the config blobs. > > It sounded like Martin wasn't going to be able to get to this until > at least the 4.18 cycle, so unless he objects I'm going to look at > getting what I've got working with that bt3wire.c driver. please go ahead - I am still busy with other things thank you for taking this over! Regards Martin