Mule is an mcu that emulates a set of i2c devices which are reachable
through an i2c-mux.
The emulated devices share a single i2c address with the mux core itself
where the requested register is what determines which logic is executed
(muxing logic or device logic):
1- The devices on the mux core can be selected (muxing functionality) 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 core to use the
i2c address of a child device. As a workaround, A new i2c-adapter quirk is
introduced to skip the check for conflict between a child device and the
mux core i2c address when adding the child device.
This patch-series adds support for this multiplexer. Mule is integrated
as part of rk3399-puma, px30-ringneck, rk3588-tiger and rk3588-jaguar
boards.
To: Wolfram Sang <[email protected]>
To: Peter Rosin <[email protected]>
To: Andi Shyti <[email protected]>
To: Rob Herring <[email protected]>
To: Krzysztof Kozlowski <[email protected]>
To: Conor Dooley <[email protected]>
To: Quentin Schulz <[email protected]>
To: Heiko Stuebner <[email protected]>
To: Quentin Schulz <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Farouk Bouabid <[email protected]>
Changes in v2:
- Add i2c-adapter quirks to skip checking for conflict between the mux core
and a child device address.
- Rename dt-binding to "tsd,mule-i2c-mux.yaml"
- Add Mule description to kconfig
- Fix indentation
- Move device table after probe
- Link to v1: https://lore.kernel.org/r/20240426-dev-mule-i2c-mux-v1-0-045a482f6ffb@theobroma-systems.com
---
Farouk Bouabid (7):
i2c: mux: add the ability to share mux core 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/tsd,mule-i2c-mux.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-core-base.c | 6 +-
drivers/i2c/i2c-mux.c | 25 +++-
drivers/i2c/muxes/Kconfig | 18 +++
drivers/i2c/muxes/Makefile | 1 +
drivers/i2c/muxes/i2c-mux-mule.c | 157 +++++++++++++++++++++
include/linux/i2c-mux.h | 1 +
include/linux/i2c.h | 7 +
12 files changed, 361 insertions(+), 12 deletions(-)
---
base-commit: 23918f4e52d072b96a4d909e91298b8dd6ad4325
change-id: 20240404-dev-mule-i2c-mux-9103cde07021
Best regards,
--
Farouk Bouabid <[email protected]>
Mule emulates an i2c mux (address 0x18). The amc6821 is exposed behind
this bus.
Add the mux node and amc6821 as a default device.
Signed-off-by: Farouk Bouabid <[email protected]>
---
arch/arm64/boot/dts/rockchip/px30-ringneck.dtsi | 20 +++++++++++++++++---
1 file changed, 17 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/boot/dts/rockchip/px30-ringneck.dtsi b/arch/arm64/boot/dts/rockchip/px30-ringneck.dtsi
index bb1aea82e666..eea906379983 100644
--- a/arch/arm64/boot/dts/rockchip/px30-ringneck.dtsi
+++ b/arch/arm64/boot/dts/rockchip/px30-ringneck.dtsi
@@ -9,6 +9,7 @@
/ {
aliases {
+ i2c10 = &i2c10;
mmc0 = &emmc;
mmc1 = &sdio;
rtc0 = &rtc_twi;
@@ -291,10 +292,23 @@ &i2c1 {
/* SE05x is limited to Fast Mode */
clock-frequency = <400000>;
- fan: fan@18 {
- compatible = "ti,amc6821";
+ i2c-mux@18 {
+ compatible = "tsd,mule-i2c-mux";
reg = <0x18>;
- #cooling-cells = <2>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c10: i2c@0 {
+ reg = <0x0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ fan: fan@18 {
+ compatible = "ti,amc6821";
+ reg = <0x18>;
+ #cooling-cells = <2>;
+ };
+ };
};
rtc_twi: rtc@6f {
--
2.34.1
On Mon, 06 May 2024 13:37:51 +0200, Farouk Bouabid wrote:
> Mule is an mcu that emulates a set of i2c devices which are reachable
> through an i2c-mux.
>
> The emulated devices share a single i2c address with the mux core itself
> where the requested register is what determines which logic is executed
> (muxing logic or device logic):
>
> 1- The devices on the mux core can be selected (muxing functionality) 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 core to use the
> i2c address of a child device. As a workaround, A new i2c-adapter quirk is
> introduced to skip the check for conflict between a child device and the
> mux core i2c address when adding the child device.
>
> This patch-series adds support for this multiplexer. Mule is integrated
> as part of rk3399-puma, px30-ringneck, rk3588-tiger and rk3588-jaguar
> boards.
>
> To: Wolfram Sang <[email protected]>
> To: Peter Rosin <[email protected]>
> To: Andi Shyti <[email protected]>
> To: Rob Herring <[email protected]>
> To: Krzysztof Kozlowski <[email protected]>
> To: Conor Dooley <[email protected]>
> To: Quentin Schulz <[email protected]>
> To: Heiko Stuebner <[email protected]>
> To: Quentin Schulz <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Farouk Bouabid <[email protected]>
>
> Changes in v2:
> - Add i2c-adapter quirks to skip checking for conflict between the mux core
> and a child device address.
> - Rename dt-binding to "tsd,mule-i2c-mux.yaml"
> - Add Mule description to kconfig
> - Fix indentation
> - Move device table after probe
>
> - Link to v1: https://lore.kernel.org/r/20240426-dev-mule-i2c-mux-v1-0-045a482f6ffb@theobroma-systems.com
>
> ---
> Farouk Bouabid (7):
> i2c: mux: add the ability to share mux core 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/tsd,mule-i2c-mux.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-core-base.c | 6 +-
> drivers/i2c/i2c-mux.c | 25 +++-
> drivers/i2c/muxes/Kconfig | 18 +++
> drivers/i2c/muxes/Makefile | 1 +
> drivers/i2c/muxes/i2c-mux-mule.c | 157 +++++++++++++++++++++
> include/linux/i2c-mux.h | 1 +
> include/linux/i2c.h | 7 +
> 12 files changed, 361 insertions(+), 12 deletions(-)
> ---
> base-commit: 23918f4e52d072b96a4d909e91298b8dd6ad4325
> change-id: 20240404-dev-mule-i2c-mux-9103cde07021
>
> Best regards,
> --
> Farouk Bouabid <[email protected]>
>
>
>
My bot found new DTB warnings on the .dts files added or changed in this
series.
Some warnings may be from an existing SoC .dtsi. Or perhaps the warnings
are fixed by another series. Ultimately, it is up to the platform
maintainer whether these warnings are acceptable or not. No need to reply
unless the platform maintainer has comments.
If you already ran DT checks and didn't see these error(s), then
make sure dt-schema is up to date:
pip3 install dtschema --upgrade
New warnings running 'make CHECK_DTBS=y rockchip/rk3588-jaguar.dtb' for [email protected]:
arch/arm64/boot/dts/rockchip/rk3588-jaguar.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#