Hi everyone, This is my fourth attempt at adding support for Allwinner's Reduced Serial Bus (RSB), which is used to communicate with PMICs and other peripherals on their newer SoCs, such as the A23/A33/A80. RSB is a simplified two wire interface using push-pull outputs, supporting multiple slaves, address and data parity checks, and clock speeds up to 20 MHz. The bus only supports simple register read/writes, with possible register sizes of 8/16/32 bits. Access sizes not matching the slave device register sizes result in NACKs or errors. 32 bit registers in devices have yet to be seen. Previous attempts to add support through the I2C subsystem have been rejected, as the bus line protocol is too different to even consider. The latest attempt to add a common bus driver was also rejected as this is sunxi only. This version adds a platform driver for the RSB controller under drivers/soc/sunxi, which adds a custom driver type and bus type for slave drivers to use. Custom regmap support is also merged into the controller driver. Currently the driver only exports 2 symbols: sunxi_rsb_driver_register() & devm_regmap_init_sunxi_rsb(). Patch 1 adds the DT bindings for Allwinner RSB controller. Patch 2 adds the driver itself. Patch 3 adds the RSB nodes for A23/A33 dtsi. Patch 5 & 5 enable the RSB controller on the boards I have. Still to come are axp20x driver support for the RSB based AXP223. The complete series can be found at: https://github.com/wens/linux/tree/sunxi-rsb-v4 This is now sunxi specific, so if everything works out, it should all go through Maxime's tree? Regards, ChenYu Chen-Yu Tsai (5): soc: sunxi: Add Allwinner Reduced Serial Bus (RSB) controller bindings soc: sunxi: Add driver for Allwinner Reduced Serial Bus ARM: dts: sun8i: Add Reduced Serial Bus controller device node to A23/A33 dtsi ARM: dts: sun8i: ippo-q8h-v5: Enable Reduced Serial Bus controller ARM: dts: sun8i: sinlinx-sina33: Enable Reduced Serial Bus controller .../devicetree/bindings/soc/sunxi/rsb.txt | 47 ++ arch/arm/boot/dts/sun8i-a23-a33.dtsi | 21 + arch/arm/boot/dts/sun8i-a23-ippo-q8h-v5.dts | 4 + arch/arm/boot/dts/sun8i-a33-sinlinx-sina33.dts | 4 + drivers/soc/sunxi/Kconfig | 10 + drivers/soc/sunxi/Makefile | 1 + drivers/soc/sunxi/sunxi_rsb.c | 786 +++++++++++++++++++++ include/linux/soc/sunxi/sunxi_rsb.h | 89 +++ 8 files changed, 962 insertions(+) create mode 100644 Documentation/devicetree/bindings/soc/sunxi/rsb.txt create mode 100644 drivers/soc/sunxi/sunxi_rsb.c create mode 100644 include/linux/soc/sunxi/sunxi_rsb.h -- 2.5.3 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html