Re: [PATCH v3 4/4] i2c: i2c-qcom-geni: Enable i2c controller sharing between two subsystems

Bryan O'Donoghue
2024-10-14T21:36:53Z

On 27/09/2024 07:31, Mukesh Kumar Savaliya wrote:
> Add support to share I2C SE by two Subsystems in a mutually exclusive way.

As I read this the question jumps out "what is a subsystem" - in Linux
speak subsystem is say a bus or a memory management method but, here
what you really mean if I've understood the intent of this series is to
share the serial engine between two different bus-masters or perhaps a
better description is "system agent".

Please make that delination clear - its not two Linux subsystems but two
different Qcom SoC bus masters right ?

For example the APSS - Application Specific Sub Subsystem - where Linux
runs and say cDSP - the compute DSP on qcom SoCs.

I'd rename this patch to make that clear - because "between two
subsystems" if you aren't intimately versed in qcom's architecture
suggests that a Linux i2c and spi driver are somehow muxing pins ..

Really this is a type of AMP - asymmetric multi processing.

"i2c: i2c-qcom-geni: Enable i2c controller sharing between two different
bus masters"

And I'd mention in the commit log specific examples - APSS yes we get
but what is the other system agent in your use-case ?

A DSP ? Some other processor in the SoC ?

Anyway highlight one use-case for this AMP case, please.

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bod