| Message ID | 20240426-dev-mule-i2c-mux-v1-0-045a482f6ffb@theobroma-systems.com |
|---|---|
| Headers | show |
| Series | Add Mule I2C multiplexer support | expand |
On Fri, 26 Apr 2024 18:49:33 +0200, Farouk Bouabid wrote: > This patch adds support for the Mule I2C multiplexer. > > Mule is an mcu that emulates a set of i2c devices which are reacheable > through an i2c-mux. > > The emulated devices share a single i2c address with the mux itself where > the requested register is what determines which logic is executed (mux or > device). > > Signed-off-by: Farouk Bouabid <farouk.bouabid@theobroma-systems.com> > --- > .../devicetree/bindings/i2c/i2c-mux-mule.yaml | 80 ++++++++++++++++++++++ > 1 file changed, 80 insertions(+) > My bot found errors running 'make dt_binding_check' on your patch: yamllint warnings/errors: dtschema/dtc warnings/errors: /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/i2c/i2c-mux-mule.example.dtb: fan@18: '#cooling-cells' does not match any of the regexes: 'pinctrl-[0-9]+' from schema $id: http://devicetree.org/schemas/trivial-devices.yaml# doc reference errors (make refcheckdocs): See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20240426-dev-mule-i2c-mux-v1-2-045a482f6ffb@theobroma-systems.com The base for the series is generally the latest rc1. A different dependency should be noted in *this* patch. If you already ran 'make dt_binding_check' and didn't see the above error(s), then make sure 'yamllint' is installed and dt-schema is up to date: pip3 install dtschema --upgrade Please check and re-submit after running the above command yourself. Note that DT_SCHEMA_FILES can be set to your schema file to speed up checking your schema. However, it must be unset to test all examples with your schema.
Hi Rob, On 26.04.24 20:22, Rob Herring wrote: > On Fri, 26 Apr 2024 18:49:33 +0200, Farouk Bouabid wrote: >> This patch adds support for the Mule I2C multiplexer. >> >> Mule is an mcu that emulates a set of i2c devices which are reacheable >> through an i2c-mux. >> >> The emulated devices share a single i2c address with the mux itself where >> the requested register is what determines which logic is executed (mux or >> device). >> >> Signed-off-by: Farouk Bouabid <farouk.bouabid@theobroma-systems.com> >> --- >> .../devicetree/bindings/i2c/i2c-mux-mule.yaml | 80 ++++++++++++++++++++++ >> 1 file changed, 80 insertions(+) >> > My bot found errors running 'make dt_binding_check' on your patch: > > yamllint warnings/errors: > > dtschema/dtc warnings/errors: > /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/i2c/i2c-mux-mule.example.dtb: fan@18: '#cooling-cells' does not match any of the regexes: 'pinctrl-[0-9]+' Currently ti,amc6821 uses trivial devices dt-bindings which does not support "#cooling-cells". We can fix this in a different patch though. Best regards Farouk
Mule is an mcu that emulates a set of i2c devices which are reacheable through an i2c-mux. The emulated devices share a single i2c address with the mux itself where the requested register is what determines which logic is executed (mux or device): 1- The devices on the mux can be selected (mux function) by writing the appropriate device number to an i2c config register (0xff) that is not used by any device logic. 2- Any access to a register other than the config register will be handled by the previously selected device. +-------------------------------------------------------+ | Mule | | +---------------+ | ----+-(1)->|Config register|-----+ | | | +---------------+ | | | | V_ | | | | \ +--------+ | | | | \-------->| dev #0 | | | | | | +--------+ | | | | M |-------->| dev #1 | | | +-----------(2)------------->| U | +--------+ | | | X |-------->| dev #2 | | | | | +--------+ | | | /-------->| dev #3 | | | |__/ +--------+ | +-------------------------------------------------------+ The current i2c-mux implementation does not allow the mux to share the i2c address of a child device. As a workaround, when creating each i2c child adapter we do not assign the parent adapter to avoid the address-match with the mux. This patch-series adds support for this multiplexer. Mule is integrated as part of rk3399-puma, px30-ringneck, rk3588-tiger and rk3588-jaguar boards. Signed-off-by: Farouk Bouabid <farouk.bouabid@theobroma-systems.com> --- Farouk Bouabid (7): i2c: mux: add the ability to share mux-address with child nodes dt-bindings: i2c: mux: mule: add dt-bindings for mule i2c multiplexer i2c: muxes: add support for mule i2c multiplexer arm64: dts: rockchip: add mule i2c mux (0x18) on rk3399-puma arm64: dts: rockchip: add mule i2c mux (0x18) on rk3588-tiger arm64: dts: rockchip: add mule i2c mux (0x18) on px30-ringneck arm64: dts: rockchip: add mule i2c mux (0x18) on rk3588-jaguar .../devicetree/bindings/i2c/i2c-mux-mule.yaml | 80 +++++++++++ arch/arm64/boot/dts/rockchip/px30-ringneck.dtsi | 20 ++- arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi | 20 ++- arch/arm64/boot/dts/rockchip/rk3588-jaguar.dts | 19 ++- arch/arm64/boot/dts/rockchip/rk3588-tiger.dtsi | 19 ++- drivers/i2c/i2c-mux.c | 10 +- drivers/i2c/muxes/Kconfig | 11 ++ drivers/i2c/muxes/Makefile | 1 + drivers/i2c/muxes/i2c-mux-mule.c | 157 +++++++++++++++++++++ include/linux/i2c-mux.h | 1 + 10 files changed, 327 insertions(+), 11 deletions(-) --- base-commit: c85af715cac0a951eea97393378e84bb49384734 change-id: 20240404-dev-mule-i2c-mux-9103cde07021 Best regards,