The MIPI I3C HCI (Host Controller Interface) specification defines a common software driver interface to support compliant MIPI I3C host controller hardware implementations from multiple vendors. This is the initial Linux driver implementing support for this specification. Due to limitations in the I3C subsystem, this driver doesn't implement everything the spec specifies. For example, scheduled commands, auto-commands and NCM are major features not yet supported. There are different revisions of the spec: v1.0, v1.1 (to be released imminently), and 2.0 (still under active development). All of them are supported with varying degree due to the above. And of course v2 support is likely to change as the spec is finalized, but it is included now as all I have for testing at the moment is based on the latest v2 draft. Even v1.0 hardware is still scarce so it hasn't been tested yet. As more hardware becomes available for testing it is expected that adjustments will be needed on top of this submission. But it is best to have the current code merged earlier so to gain better exposure and to create an incentive for future contributions. Feedback appreciated. Changes from v2: - resync with latest draft of HCI v1.1 and v2 specs, especially the v2 cmd descriptor format and new error codes - more extended capability table parsing from the v2 spec - tightened PIO error handling somewhat - minor cosmetic changes - precision on the DT binding based on Rob Herring's review - small changes based on Miquel Raynal's review - small changes based on Boris Brezillon's review - some more small changes based on Sakari Ailus' review Changes from v1: - moved DT binding to schema format (Rob) - fix sparse warnings (kernel test robot) - fix build warnings on 32-bit targets (kernel test robot) - avoid PIO_OFFSET symbol conflict (kernel test robot) - minor cosmetic changes diffstat: .../devicetree/bindings/i3c/mipi-i3c-hci.yaml | 45 + drivers/i3c/master/Kconfig | 13 + drivers/i3c/master/Makefile | 1 + drivers/i3c/master/mipi-i3c-hci/Makefile | 6 + drivers/i3c/master/mipi-i3c-hci/cmd.h | 67 ++ drivers/i3c/master/mipi-i3c-hci/cmd_v1.c | 378 ++++++ drivers/i3c/master/mipi-i3c-hci/cmd_v2.c | 309 +++++ drivers/i3c/master/mipi-i3c-hci/core.c | 798 +++++++++++++ drivers/i3c/master/mipi-i3c-hci/dat.h | 32 + drivers/i3c/master/mipi-i3c-hci/dat_v1.c | 184 +++ drivers/i3c/master/mipi-i3c-hci/dct.h | 16 + drivers/i3c/master/mipi-i3c-hci/dct_v1.c | 36 + drivers/i3c/master/mipi-i3c-hci/dma.c | 784 +++++++++++++ drivers/i3c/master/mipi-i3c-hci/ext_caps.c | 308 +++++ drivers/i3c/master/mipi-i3c-hci/ext_caps.h | 19 + drivers/i3c/master/mipi-i3c-hci/hci.h | 144 +++ drivers/i3c/master/mipi-i3c-hci/ibi.h | 42 + drivers/i3c/master/mipi-i3c-hci/pio.c | 1041 +++++++++++++++++ .../i3c/master/mipi-i3c-hci/xfer_mode_rate.h | 79 ++ 19 files changed, 4302 insertions(+)