MIPI SLIMbus core and Qualcomm NGD controller
SLIMbus is a MIPI-standard serial interconnect that links a system-on-chip's application processor to audio codecs and other peripherals, used heavily inside Qualcomm Snapdragon-based phones, tablets, and embedded boards. This subsystem provides the generic SLIMbus framework plus the Qualcomm Non-Generic Device (NGD) controller driver that talks to the bus on those SoCs.
recommendation
It should stay because SLIMbus is still a current piece of Qualcomm SoC designs, including modern parts like the QRB5165, and the kernel code is actively maintained: Qualcomm engineers were posting fixes to the NGD controller as recently as 2026, with backports flowing into stable kernels. Deployment is narrow (mobile and embedded Qualcomm platforms rather than PCs or servers), but there is no replacement and the documentation describes it as a live, supported bus.
repository signals
sources
- lore.kernel.org
Recent upstream work is still landing for this code: Bjorn Andersson posted a 2026 fix to `slimbus: qcom-ngd-ctrl`.
- lore.kernel.org
That SLIMbus controller fix was backported into a 2026 stable release, indicating ongoing supported deployments rather than orphaned code.
- docs.kernel.org
Kernel documentation describes SLIMbus as a live SoC-to-peripheral interconnect used mainly between application processors and codecs/peripherals.
- docs.qualcomm.com
Qualcomm's QRB5165 datasheet includes a dedicated SLIMbus interface section, showing the bus still appears in modern Qualcomm platforms.
codex reasoning notes (technical)
Local tree inspection shows this is a real driver/bus subsystem (`slimbus.o` core plus `qcom-ngd-ctrl` platform driver), not helper-only code. `lore_file_timeline` on `drivers/slimbus/qcom-ngd-ctrl.c` returned 2026 patch and stable-backport URLs, with heavy activity through 2026, so upstream attention is current and there is no sign here of removal. Web search returned the docs.kernel.org SLIMbus API page and Qualcomm QRB5165 datasheet URL; together they show SLIMbus remains a documented kernel bus and is still present on contemporary Qualcomm hardware. Deployment is not broad across general-purpose PCs/servers, so I rate it `low`, but it is still relevant in embedded/mobile/Qualcomm audio designs. No direct drop-in replacement driver exists for the same hardware class, so `replacement_driver` is null.