[PATCH] ARM: dts: aspeed: yosemite5: add x4 E1.S expansion board I2C mux

Kevin Tung posted 1 patch 1 month, 2 weeks ago
.../dts/aspeed/aspeed-bmc-facebook-yosemite5.dts   | 23 ++++++++++++++++++++++
1 file changed, 23 insertions(+)
[PATCH] ARM: dts: aspeed: yosemite5: add x4 E1.S expansion board I2C mux
Posted by Kevin Tung 1 month, 2 weeks ago
The new hardware design adds two additional E1.S devices behind an
I2C mux at address 0x73 on bus 10. Add support for this mux in the
DTS device tree.

Signed-off-by: Kevin Tung <kevin.tung.openbmc@gmail.com>
---
Summary:
Revise linux device tree entry related to Meta (Facebook) Yosemite5.

Changes in v1:
- Add x4 E1.S expansion board I2C mux
---
 .../dts/aspeed/aspeed-bmc-facebook-yosemite5.dts   | 23 ++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts
index 2486981f3d6bd36f3fe780b21e834b85242f8aa9..87524892322c1388c146b33ac454018a31dad168 100644
--- a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts
+++ b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts
@@ -31,6 +31,8 @@ aliases {
 		i2c33 = &i2c30mux0ch1;
 		i2c34 = &i2c30mux0ch2;
 		i2c35 = &i2c30mux0ch3;
+		i2c36 = &i2c10mux0ch0;
+		i2c37 = &i2c10mux0ch1;
 		serial0 = &uart1;
 		serial2 = &uart3;
 		serial3 = &uart4;
@@ -702,6 +704,27 @@ eeprom@54 {
 		compatible = "atmel,24c128";
 		reg = <0x54>;
 	};
+
+	/* I2C MUX on E1S x4 board */
+	i2c-mux@73 {
+		compatible = "nxp,pca9543";
+		reg = <0x73>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		i2c-mux-idle-disconnect;
+
+		i2c10mux0ch0: i2c@0 {
+			reg = <0>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+		};
+
+		i2c10mux0ch1: i2c@1 {
+			reg = <1>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+		};
+	};
 };
 
 &i2c11 {

---
base-commit: 9448598b22c50c8a5bb77a9103e2d49f134c9578
change-id: 20251222-yv5_add_dvt_e1s_ioexp-14930e048043

Best regards,
-- 
Kevin Tung <kevin.tung.openbmc@gmail.com>
Re: [PATCH] ARM: dts: aspeed: yosemite5: add x4 E1.S expansion board I2C mux
Posted by Andrew Jeffery 1 month ago
On Mon, 2025-12-22 at 19:25 +0800, Kevin Tung wrote:
> The new hardware design adds two additional E1.S devices behind an
> I2C mux at address 0x73 on bus 10. Add support for this mux in the
> DTS device tree.

Out of curiosity, you're monitoring them with the NVMe-MI basic
management command and not NVMe-MI over MCTP, or is there something
else going on which motivates describing empty mux legs?

Andrew
Re: [PATCH] ARM: dts: aspeed: yosemite5: add x4 E1.S expansion board I2C mux
Posted by Kevin Tung 1 week, 3 days ago
On Thu, Jan 8, 2026 at 12:46 PM Andrew Jeffery
<andrew@codeconstruct.com.au> wrote:
>
> On Mon, 2025-12-22 at 19:25 +0800, Kevin Tung wrote:
> > The new hardware design adds two additional E1.S devices behind an
> > I2C mux at address 0x73 on bus 10. Add support for this mux in the
> > DTS device tree.
>
> Out of curiosity, you're monitoring them with the NVMe-MI basic
> management command and not NVMe-MI over MCTP, or is there something
> else going on which motivates describing empty mux legs?
>
> Andrew

Hi Andrew,

We’re monitoring them using the NVMe-MI basic management commands
directly, which is why the empty mux legs are described.

Kevin