Here is finally the first RFC of a driver for the Renesas I3C IP. It was created by merging two versions of it from two different BSPs. Then, improved according to code analyzers, cleaned up with regard to coding style, and then refactored to hopefully match I3C subsystem standards. It is a basic driver for the I3C IP found in various SoCs like RZ/G3S and G3E. Missing features to be added incrementally are IBI, HotJoin and maybe target support. Other than that, this driver has been tested with I3C pure busses (2 targets) and mixed busses (2 I3C + various I2C targets). DAA and reading/writing to the temperature sensors worked reliably at different speeds. Scoping the bus, the output from the protocol analyzer seems reasonable, too. But hey, I am still new to all this, so I might have overlooked something. The first patches are needed to enable I3C on the RZ/G3S and G3E boards. Once this series loses RFC status, they will be sent out individually, of course. All is on top of 6.16-rc1. A branch can be found here: git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git renesas/g3s/i3c Why is this still RFC? - On G3E (but not G3S), we get a spurious irq during boot. We are working on it. This is just platform dependent, though, kind of independent of the high level design of the driver. For this, we would love to get comments already. So, we can fix things in parallel - G3S has 17 irqs, G3E only 16. The way we handle this might need discussion (see patch 3) - On G3S, clocks are named 'i3c' while on G3E they are named 'i3c0' I don't have all the needed docs for this, but Tommaso can surely figure this out meanwhile - There are some open questions regarding the driver itself (see patch 4) Really looking forward to comments! This has been quite a ride. Getting a suitable test setup was a surprisingly big task. If someone knows an off-the-shelf device supporting HotJoin, I am all ears. I couldn't find one. So much for now here, some patches have more details. All the best, Wolfram Quynh Nguyen (1): arm64: dts: renesas: r9a08g045: Add I3C node Tommaso Merciai (3): clk: renesas: r9a09g047: Add I3C0 clocks and resets dt-bindings: i3c: renesas,i3c: Add binding for Renesas I3C controller arm64: dts: renesas: r9a09g047: Add I3C node Wolfram Sang (3): clk: renesas: r9a08g045: Add I3C clocks, resets and power domain i3c: add driver for Renesas I3C IP WIP: arm64: dts: renesas: rzg3s-smarc-som: Enable I3C .../devicetree/bindings/i3c/renesas,i3c.yaml | 186 +++ MAINTAINERS | 7 + arch/arm64/boot/dts/renesas/r9a08g045.dtsi | 35 + arch/arm64/boot/dts/renesas/r9a09g047.dtsi | 35 + .../boot/dts/renesas/rzg3s-smarc-som.dtsi | 33 + drivers/clk/renesas/r9a08g045-cpg.c | 7 + drivers/clk/renesas/r9a09g047-cpg.c | 8 + drivers/i3c/master/Kconfig | 10 + drivers/i3c/master/Makefile | 1 + drivers/i3c/master/renesas-i3c.c | 1441 +++++++++++++++++ 10 files changed, 1763 insertions(+) create mode 100644 Documentation/devicetree/bindings/i3c/renesas,i3c.yaml create mode 100644 drivers/i3c/master/renesas-i3c.c -- 2.47.2
