Subject: RE: [External Mail] Re: [PATCH 00/11] net: wwan: t9xx: Add MediaTek T9XX WWAN driver

From: "Wu. JackBB (GSM)" <[email-masked]>
Date: Tue, 2 Jun 2026 09:28:43 +0000

Hi Loic,

>
> Hi Jack,
>
> On Fri, May 29, 2026 at 12:31 PM Jack Wu via B4 Relay
> <[email-masked]> wrote:
> >
> > T9XX is the PCIe host device driver for MediaTek's
> > t900 modem. The driver uses the WWAN framework
> > infrastructure to create the following control ports
> > and network interfaces for data transactions.
> > * /dev/wwan0at0 - Interface that supports AT commands.
> > * /dev/wwan0mbim0 - Interface conforming to the MBIM
> > protocol.
> > * wwan0-X - Primary network interface for IP traffic.
> >
> > The main blocks in the T9XX driver are:
> > * HW layer - Abstracts the hardware bus operations for
> > the device, and provides generic interfaces for the
> > transaction layer to get the device's information and
> > control the device's behavior. It includes:
> >
> > * PCIe - Implements probe, removal and interrupt
> > handling.
> > * MHCCIF (Modem Host Cross-Core Interface) - Provides
> > interrupt channels for bidirectional event
> > notification such as handshake and port enumeration.
> >
> > * Transaction layer - Implements data transactions for
> > the control plane and the data plane. It includes:
> >
> > * DPMAIF (Data Plane Modem AP Interface) - Controls
> > the hardware that provides uplink and downlink
> > queues for the data path. The data exchange takes
> > place using circular buffers to share data buffer
> > addresses and metadata to describe the packets.
> > * CLDMA (Cross Layer DMA) - Manages the hardware
> > used by the port layer to send control messages to
> > the device using MediaTek's CCCI (Cross-Core
> > Communication Interface) protocol.
> > * TX Services - Dispatch packets from the port layer
> > to the device.
> > * RX Services - Dispatch packets to the port layer
> > when receiving packets from the device.
> >
> > * Port layer - Provides control plane and data plane
> > interfaces to userspace. It includes:
> >
> > * Control Plane - Provides device node interfaces
> > for controlling data transactions.
> > * Data Plane - Provides network link interfaces
> > wwanX (0, 1, 2...) for IP data transactions.
> >
> > * Core logic - Contains the core logic to keep the
> > device working. It includes:
> >
> > * FSM (Finite State Machine) - Monitors the state
> > of the device, and notifies each module when the
> > state changes.
> >
> > The compilation of the T9XX driver is enabled by the
> > CONFIG_MTK_T9XX and CONFIG_MTK_T9XX_PCI config option
> > which depends on CONFIG_WWAN.
>
> Can you specify which userspace counterpart you need (e.g., a
> ModemManager version or a link to the relevant patch series)?
>
The driver is agnostic to the userspace application. We verified
functionality using ModemManager v1.23.4 and v1.25.95, and both
work out of the box.
>
> >
> > ---
> > Jack Wu (11):
> > net: wwan: t9xx: Add PCIe core
> > net: wwan: t9xx: Add control plane transaction layer
> > net: wwan: t9xx: Add control DMA interface
> > net: wwan: t9xx: Add control port
> > net: wwan: t9xx: Add FSM thread
> > net: wwan: t9xx: Add AT & MBIM WWAN ports
> > net: wwan: t9xx: Introduce data plane hardware
> > net: wwan: t9xx: Add data plane transaction layer
> > net: wwan: t9xx: Introduce WWAN interface
> > net: wwan: t9xx: Add power management support
> > net: wwan: t9xx: Add maintainers and documentation
> >
> > .../networking/device_drivers/wwan/t9xx.rst | 48 +
> > MAINTAINERS | 10 +
> > drivers/net/wwan/Kconfig | 17 +
> > drivers/net/wwan/Makefile | 1 +
> > drivers/net/wwan/t9xx/Makefile | 16 +
> > drivers/net/wwan/t9xx/mtk_ctrl_plane.c | 95 +
> > drivers/net/wwan/t9xx/mtk_ctrl_plane.h | 88 +
> > drivers/net/wwan/t9xx/mtk_data_plane.c | 104 +
> > drivers/net/wwan/t9xx/mtk_data_plane.h | 105 +
> > drivers/net/wwan/t9xx/mtk_dev.c | 55 +
> > drivers/net/wwan/t9xx/mtk_dev.h | 114 +
> > drivers/net/wwan/t9xx/mtk_fsm.c | 931 +++++++
> > drivers/net/wwan/t9xx/mtk_fsm.h | 140 +
> > drivers/net/wwan/t9xx/mtk_port.c | 967 +++++++
> > drivers/net/wwan/t9xx/mtk_port.h | 176 ++
> > drivers/net/wwan/t9xx/mtk_port_io.c | 576 +++++
> > drivers/net/wwan/t9xx/mtk_port_io.h | 41 +
> > drivers/net/wwan/t9xx/mtk_utility.h | 33 +
> > drivers/net/wwan/t9xx/mtk_wwan.c | 475 ++++
> > drivers/net/wwan/t9xx/mtk_wwan.h | 17 +
> > drivers/net/wwan/t9xx/pcie/Makefile | 19 +
> > drivers/net/wwan/t9xx/pcie/mtk_cldma.c | 1527 +++++++++++
> > drivers/net/wwan/t9xx/pcie/mtk_cldma.h | 176 ++
> > drivers/net/wwan/t9xx/pcie/mtk_cldma_drv.c | 373 +++
> > drivers/net/wwan/t9xx/pcie/mtk_cldma_drv.h | 174 ++
> > drivers/net/wwan/t9xx/pcie/mtk_cldma_drv_m9xx.c | 177 ++
> > drivers/net/wwan/t9xx/pcie/mtk_cldma_drv_m9xx.h | 101 +
> > drivers/net/wwan/t9xx/pcie/mtk_ctrl_cfg_m9xx.c | 55 +
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif.c | 2714 ++++++++++++++++++++
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif.h | 16 +
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif_drv.c | 1586 ++++++++++++
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif_drv.h | 268 ++
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif_drv_m9xx.c | 687 +++++
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif_reg.h | 387 +++
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif_reg_m9xx.h | 37 +
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif_ring.c | 168 ++
> > drivers/net/wwan/t9xx/pcie/mtk_dpmaif_ring.h | 161 ++
> > drivers/net/wwan/t9xx/pcie/mtk_pci.c | 1067 ++++++++
> > drivers/net/wwan/t9xx/pcie/mtk_pci.h | 219 ++
> > drivers/net/wwan/t9xx/pcie/mtk_pci_drv_m9xx.c | 70 +
> > drivers/net/wwan/t9xx/pcie/mtk_pci_reg.h | 72 +
> > drivers/net/wwan/t9xx/pcie/mtk_trans_ctrl.c | 593 +++++
> > drivers/net/wwan/t9xx/pcie/mtk_trans_ctrl.h | 105 +
> > 43 files changed, 14761 insertions(+)
> > ---
> > base-commit: eb3f4b7426cfd2b79d65b7d37155480b32259a11
> > change-id: 20260529-t9xx_driver_v1-1744f8af7739
> >
> > Best regards,
> > --
> > Jack Wu <[email-masked]>

================================================================================================================================================================
This message may contain information which is private, privileged or confidential of Compal Electronics, Inc. If you are not the intended recipient of this message, please notify the sender and destroy/delete the message. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon this information, by persons or entities other than the intended recipient is prohibited.
================================================================================================================================================================