[PATCH 11/11] net: wwan: t9xx: Add maintainers and documentation

[Jack Wu via B4 Relay]

From: Jack Wu <jackbb_wu@xxxxxxxxxx>

Adds maintainers and documentation for MediaTek T9XX 5G WWAN modem
device driver.

Signed-off-by: Jack Wu <jackbb_wu@xxxxxxxxxx>
---
 .../networking/device_drivers/wwan/t9xx.rst        | 48 ++++++++++++++++++++++
 MAINTAINERS                                        | 10 +++++
 2 files changed, 58 insertions(+)

diff --git a/Documentation/networking/device_drivers/wwan/t9xx.rst b/Documentation/networking/device_drivers/wwan/t9xx.rst
new file mode 100644
index 000000000000..eaba82f18c1b
--- /dev/null
+++ b/Documentation/networking/device_drivers/wwan/t9xx.rst
@@ -0,0 +1,48 @@
+.. SPDX-License-Identifier: GPL-2.0-only
+
+.. Copyright (c) 2025, MediaTek Inc.
+
+.. _t9xx_driver_doc:
+
+====================================================
+T9XX driver for MTK PCIe based T-series 5G Modem
+====================================================
+The T9XX driver is a WWAN PCIe host driver developed
+for data exchange over PCIe interface between Host platform and MediaTek's
+T-series 5G modem. The driver exposes control plane and data plane interfaces
+to applications. The control plane provides device node interfaces for control
+data transactions. The data plane provides network link interfaces for IP data
+transactions.
+
+Control channel userspace ABI
+=============================
+/dev/wwan0at0 character device
+------------------------------
+The driver exposes an AT port by implementing AT WWAN Port.
+The userspace end of the control channel pipe is a /dev/wwan0at0 character
+device. Application shall use this interface to issue AT commands.
+
+/dev/wwan0mbim0 character device
+--------------------------------
+The driver exposes an MBIM interface to the MBIM function by implementing
+MBIM WWAN Port. The userspace end of the control channel pipe is a
+/dev/wwan0mbim0 character device. Applications shall use this interface
+for MBIM protocol communication.
+
+Data channel userspace ABI
+==========================
+wwan0-X network device
+----------------------
+The T9XX driver exposes IP link interfaces "wwan0-X" of type "wwan" for IP
+traffic. Iproute network utility is used for creating "wwan0-X" network
+interfaces and for associating it with the MBIM IP session.
+
+The userspace management application is responsible for creating a new IP link
+prior to establishing an MBIM IP session where the SessionId is greater than 0.
+
+For example, creating a new IP link for an MBIM IP session with SessionId 1:
+
+  ip link add dev wwan0-1 parentdev wwan0 type wwan linkid 1
+
+The driver will automatically map the "wwan0-1" network device to MBIM IP
+session 1.
diff --git a/MAINTAINERS b/MAINTAINERS
index 461a3eed6129..3fab2b47f531 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16494,6 +16494,16 @@ L:	netdev@xxxxxxxxxxxxxxx
 S:	Supported
 F:	drivers/net/wwan/t7xx/
 
+MEDIATEK T9XX 5G WWAN MODEM DRIVER
+M:	Jack Wu <jackbb_wu@xxxxxxxxxx>
+R:	Wen-Zhi Huang <wen-zhi.huang@xxxxxxxxxxxx>
+R:	Shi-Wei Yeh <shi-wei.yeh@xxxxxxxxxxxx>
+R:	Minano Tseng <Minano.tseng@xxxxxxxxxxxx>
+L:	netdev@xxxxxxxxxxxxxxx
+S:	Supported
+F:	Documentation/networking/device_drivers/wwan/t9xx.rst
+F:	drivers/net/wwan/t9xx/
+
 MEDIATEK USB3 DRD IP DRIVER
 M:	Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
 L:	linux-usb@xxxxxxxxxxxxxxx

-- 
2.34.1