Re:[RFC PATCH v5 0/7] net: wwan: add NMEA port type support
From: Slark Xiao <hidden>
Date: 2026-01-09 03:22:26
At 2026-01-09 09:09:02, "Sergey Ryazanov" [off-list ref] wrote:
The series introduces a long discussed NMEA port type support for the WWAN subsystem. There are two goals. From the WWAN driver perspective, NMEA exported as any other port type (e.g. AT, MBIM, QMI, etc.). From user space software perspective, the exported chardev belongs to the GNSS class what makes it easy to distinguish desired port and the WWAN device common to both NMEA and control (AT, MBIM, etc.) ports makes it easy to locate a control port for the GNSS receiver activation. Done by exporting the NMEA port via the GNSS subsystem with the WWAN core acting as proxy between the WWAN modem driver and the GNSS subsystem. The series starts from a cleanup patch. Then three patches prepares the WWAN core for the proxy style operation. Followed by a patch introding a new WWNA port type, integration with the GNSS subsystem and demux. The series ends with a couple of patches that introduce emulated EMEA port to the WWAN HW simulator. The series is the product of the discussion with Loic about the pros and cons of possible models and implementation. Also Muhammad and Slark did a great job defining the problem, sharing the code and pushing me to finish the implementation. Daniele has caught an issue on driver unloading and suggested an investigation direction. What was concluded by Loic. Many thanks. Slark, if this series with the unregister fix suits you, please bundle it with your MHI patch, and (re-)send for final inclusion. Changes RFCv1->RFCv2: * Uniformly use put_device() to release port memory. This made code less weird and way more clear. Thank you, Loic, for noticing and the fix discussion! Changes RFCv2->RFCv5: * Fix premature WWAN device unregister; new patch 2/7, thus, all subsequent patches have been renumbered * Minor adjustments here and there
Shall I keep these RFC changes info in my next commit? Also these RFC changes info in these single patch. And I want to know whether v5 or v6 shall be used for my next serial? Is there a review progress for these RFC patches ( for patch 2/7 and 3/7 especially). If yes, I will hold my commit until these review progress finished. If not, I will combine these changes with my MHI patch and send them out asap.
CC: Slark Xiao <redacted> CC: Muhammad Nuzaihan <redacted> CC: Daniele Palmas <redacted> CC: Qiang Yu <redacted> CC: Manivannan Sadhasivam <mani@kernel.org> CC: Johan Hovold <johan@kernel.org> Sergey Ryazanov (7): net: wwan: core: remove unused port_id field net: wwan: core: explicit WWAN device reference counting net: wwan: core: split port creation and registration net: wwan: core: split port unregister and stop net: wwan: add NMEA port support net: wwan: hwsim: refactor to support more port types net: wwan: hwsim: support NMEA port emulation drivers/net/wwan/Kconfig | 1 + drivers/net/wwan/wwan_core.c | 280 +++++++++++++++++++++++++++------- drivers/net/wwan/wwan_hwsim.c | 201 +++++++++++++++++++----- include/linux/wwan.h | 2 + 4 files changed, 396 insertions(+), 88 deletions(-) -- 2.52.0