add support for Bluetooth on MT7622 SoC

From: Sean Wang <[email protected]>

v8 and changes since v7:
- add updates per these suggestions mentioned in [1][2]
- remove the hack atomic_inc(&hdev->cmd_cnt) mentioned in [2] because it should be better to be considered in the core

[1] http://lists.infradead.org/pipermail/linux-mediatek/2018-August/014516.html
[2] http://lists.infradead.org/pipermail/linux-mediatek/2018-August/014518.html

v7 and changes since v6:
- drop already applied patches
- move clk_* and pm_* operation to ->open and ->close
- label this driver as BT_MTKUART
- make code style aligned with the other drivers and code better to read as these suggestions and fixes are mentioned in [1]

[1] http://lists.infradead.org/pipermail/linux-mediatek/2018-July/014458.html

v6 and changes since v5:
- make btmtkuart become a separate driver.
- drop already applied patches and the patch for btuart driver
- refine comments in driver allowing people know that mtk extra header
+ length doesn't indicate a full H:4 frame, things can fragment.
- enhance dt-binding document with removing mistaken added " and improve English sentence.
- remove unnecessary '\n' with bt_dev_err.
- refine code style.
- set hdev->manufacturer as mtk id.

v5 and changes since v4:
- add Reviewed-by Tag from Ulf Hansson for patch 2
- remove default y in Kconfig for btmtkuart selection to avoid overkill for users which would like to have less an amount on stuff in kernel.
- list header declarations in alphabetical order and add a proper blank line within.
- remove unused macro.
- use sizeof to calculate structure size instead of an aextra macro to hardcode.
- use struct hci_dev * as input paraments for mtk_hci_wmt_sync and mtk_setup_fw for that can be reused in mtk bluetooth with other interfaces.
- remove unused local variabled in mtk_btuart_recv.
- remove superfluous :8 for dlen2 in struct mtk_stp_hdr definition.
- give a reasonable naming for these labels and add a pm_runtime_put_noidle() in the path undoing failing pm_runtime_get_sync().
- Turn __u8 into u8 in struct mtk_stp_hdr.

Really thanks for these reviews by Johan Hovold and Andy Shevchenko

v4 and changes since v3:
- refine patch 2 based on commit 919b7308fcc4 to allow that dev_pm_domain_attach() will return better error codes.

v3 and changes since v2
* all changes happen on patch 6
- fix up SPDX license style for btmtkuart.h.
- change firmware download from in ACL data to in HCI commands and then remove unused mtk_acl_wmt_sync and related code.
- add a workaround replacing bad vendor event id 0xe4 with 0xff every vendor should use.
- add a sanity check for mtk_hci_wmt_sync to verifying if input parameters are valid.
- add an atomic_inc(&bdev->hdev->cmd_cnt) for __hci_cmd_sync_ev.
- be changed to use firmware with a header called mt7622pr2h.bin.

v2 and changes since v1
- Dropped patches already being applied
- Rewirte the whole driver using btuart [1], and add slight extension of btuart to fit into btmtkuart driver. Beware that [1] is also pulled into one part of the series for avoiding any breakage when the patchset is being compiled.

[1] btuart

	https://www.spinics.net/lists/linux-bluetooth/msg74918.html

v1:

Hi,

This patchset introduces built-in Bluetooth support on MT7622 SoC. And, it should be simple to make an extension to support other MediaTek SoCs with adjusting a few of changes on the initialization sequence of the device.

Before the main driver is being introduced, a few of things about power-domain management should be re-worked for serdev core and MediaTek SCPSYS to allow the Bluetooth to properly power up.

Patch 2: add a generic way attaching power domain to serdev Patch 3 and 4: add cleanups with reuse APIs from Linux core Patch 5: fix a limitation about power enablement Bluetooth depends on Patch 1, 6 and 7: the major part of adding Bluetooth support to MT7622

Sean

Sean Wang (3):
dt-bindings: net: bluetooth: Add mediatek-bluetooth
Bluetooth: mediatek: Add protocol support for MediaTek serial devices
MAINTAINERS: add an entry for MediaTek Bluetooth driver

 .../devicetree/bindings/net/mediatek-bluetooth.txt |  35 ++
 MAINTAINERS                                        |   8 +
 drivers/bluetooth/Kconfig                          |  11 +
 drivers/bluetooth/Makefile                         |   2 +
 drivers/bluetooth/btmtkuart.c                      | 588 +++++++++++++++++++++
 5 files changed, 644 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/mediatek-bluetooth.txt
 create mode 100644 drivers/bluetooth/btmtkuart.c

2.7.4

From: Sean Wang <[email protected]>

Add binding document for a SoC built-in device using MediaTek protocol. Which could be found on MT7622 SoC or other similar MediaTek SoCs.

---
 .../devicetree/bindings/net/mediatek-bluetooth.txt | 35 ++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/mediatek-bluetooth.txt

new file mode 100644
index 0000000..14ceb2a
@@ -0,0 +1,35 @@
+MediaTek SoC built-in Bluetooth Devices
+==================================
+
+This device is a serial attached device to BTIF device and thus it must be a
+child node of the serial node with BTIF. The dt-bindings details for BTIF
+device can be known via Documentation/devicetree/bindings/serial/8250.txt.
+
+Required properties:
+
+- compatible:	Must be
+		  "mediatek,mt7622-bluetooth": for MT7622 SoC
+- clocks:	Should be the clock specifiers corresponding to the entry in
+		clock-names property.
+- clock-names:	Should contain "ref" entries.
+- power-domains: Phandle to the power domain that the device is part of
+
+Example:
+
+	btif: serial at 1100c000 {
+		compatible = "mediatek,mt7622-btif",
+			     "mediatek,mtk-btif";
+		reg = <0 0x1100c000 0 0x1000>;
+		interrupts = <GIC_SPI 90 IRQ_TYPE_LEVEL_LOW>;
+		clocks = <&pericfg CLK_PERI_BTIF_PD>;
+		clock-names = "main";
+		reg-shift = <2>;
+		reg-io-width = <4>;
+
+		bluetooth {
+			compatible = "mediatek,mt7622-bluetooth";
+			power-domains = <&scpsys MT7622_POWER_DOMAIN_WB>;
+			clocks = <&clk25m>;
+			clock-names = "ref";
+		};
+	};

2.7.4

From: Sean Wang <[email protected]>

This adds a driver based on serdev driver for the MediaTek serial protocol based on running H:4, which can enable the built-in Bluetooth device inside MT7622 SoC.

---
 drivers/bluetooth/Kconfig     |  11 +
 drivers/bluetooth/Makefile    |   2 +
 drivers/bluetooth/btmtkuart.c | 588 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 601 insertions(+)
 create mode 100644 drivers/bluetooth/btmtkuart.c

index f3c643a..5ace676 100644
@@ -74,6 +74,17 @@ config BT_HCIBTSDIO
 	  Say Y here to compile support for Bluetooth SDIO devices into the
 	  kernel or say M to compile it as module (btsdio).
 
+config BT_MTKUART
+	tristate "MediaTek HCI UART driver"
+	depends on SERIAL_DEV_BUS
+	help
+	  MediaTek Bluetooth HCI UART driver.
+	  This driver is required if you want to use MediaTek Bluetooth
+	  with serial interface.
+
+	  Say Y here to compile support for MediaTek Bluetooth UART devices
+	  into the kernel or say M to compile it as module (btmtkuart).
+
 config BT_HCIUART
 	tristate "HCI UART driver"
 	depends on SERIAL_DEV_BUS || !SERIAL_DEV_BUS

index ec16c55..12ad6e9 100644
@@ -25,6 +25,8 @@ obj-$(CONFIG_BT_BCM)		+= btbcm.o
 obj-$(CONFIG_BT_RTL)		+= btrtl.o
 obj-$(CONFIG_BT_QCA)		+= btqca.o
 
+obj-$(CONFIG_BT_MTKUART)	+= btmtkuart.o
+
 obj-$(CONFIG_BT_HCIUART_NOKIA)	+= hci_nokia.o
 
 obj-$(CONFIG_BT_HCIRSI)		+= btrsi.o

2.7.4

From: Sean Wang <[email protected]>

Add an entry for the MediaTek Bluetooth driver.

---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

index 0f2cce4..e983d9e 100644
@@ -9144,6 +9144,14 @@ F:	include/uapi/linux/meye.h
 F:	include/uapi/linux/ivtv*
 F:	include/uapi/linux/uvcvideo.h
 
+MEDIATEK BLUETOOTH DRIVER
+M:	Sean Wang <[email protected]>
+L:	linux-bluetooth at vger.kernel.org
+L:	linux-mediatek at lists.infradead.org (moderated for non-subscribers)
+S:	Maintained
+F:	Documentation/devicetree/bindings/net/mediatek-bluetooth.txt
+F:	drivers/bluetooth/btmtkuart.c
+
 MEDIATEK CIR DRIVER
 M:	Sean Wang <[email protected]>
 S:	Maintained

2.7.4