Re: [PATCH v4 5/7] ARM: dts: aspeed: yosemite5: Correct power monitor shunt resistor
From: Andrew Jeffery <andrew@codeconstruct.com.au>
Date: 2026-02-09 06:21:03
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linux-arm-kernel, linux-devicetree, lkml
Hi Kevin, On Fri, 2026-01-30 at 16:20 +0800, Kevin Tung wrote:
The shunt resistor value defined in the DTS was incorrect and did not reflect the resistor value populated on the board. As a result, power and current readings derived from this value were inaccurate.
Okay, but how did it come to be incorrect in the devicetree? Was the documentation wrong and so someone entered the wrong value? Was the documentation correct but there was a misunderstanding? Did the hardware design change and the devicetree is now just inappropriate for your needs? Essentially, what's preventing this from happening again?
This change
I'd rather you rephrase this to avoid using "This change ...". Hopefully the commit message always refers to its change. Generally, please write in the imperative mood (see [1]) [1]: https://docs.kernel.org/process/submitting-patches.html#describe-your-changes
quoted hunk ↗ jump to hunk
updates the DTS to use the correct shunt resistor value according to the hardware design, restoring accurate power and current measurements. Signed-off-by: Kevin Tung <redacted> --- arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)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 84d3731b17f7c7c87338672bbcc859de2b89b722..524597a81365ef10cd03b67d35eeb88a965cbe0a 100644 --- a/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts +++ b/arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-yosemite5.dts@@ -415,7 +415,7 @@ power-sensor@42 {power-monitor@43 { compatible = "lltc,ltc4287"; reg = <0x43>; - shunt-resistor-micro-ohms = <250>; + shunt-resistor-micro-ohms = <100>; }; power-sensor@44 {@@ -461,25 +461,25 @@ eeprom@57 {power-monitor@58 { compatible = "renesas,isl28022"; reg = <0x58>; - shunt-resistor-micro-ohms = <1000>; + shunt-resistor-micro-ohms = <10000>; }; power-monitor@59 { compatible = "renesas,isl28022"; reg = <0x59>; - shunt-resistor-micro-ohms = <1000>; + shunt-resistor-micro-ohms = <10000>; }; power-monitor@5a { compatible = "renesas,isl28022"; reg = <0x5a>; - shunt-resistor-micro-ohms = <1000>; + shunt-resistor-micro-ohms = <10000>; }; power-monitor@5b { compatible = "renesas,isl28022"; reg = <0x5b>; - shunt-resistor-micro-ohms = <1000>; + shunt-resistor-micro-ohms = <10000>; }; psu@5c {@@ -723,13 +723,13 @@ gpio-expander@21 {power-sensor@40 { compatible = "ti,ina230"; reg = <0x40>; - shunt-resistor = <2000>; + shunt-resistor = <1000>; }; power-sensor@41 { compatible = "ti,ina230"; reg = <0x41>; - shunt-resistor = <2000>; + shunt-resistor = <1000>; }; power-sensor@42 {
The way the commit message is written suggests it was just one shunt resistor, but that's clearly not the case. Andrew