Re: [RFC PATCH 6/6] rust: cpufreq: Add rust implementation of cppc_cpufreq driver

[Greg KH]

On Thu, Aug 15, 2024 at 10:29:10AM +0200, Pierre Gondois wrote:
> In an effort to add test/support the cpufreq framework in rust,
> add a rust implementation of the cppc_cpufreq driver named:
> `rcppc_cpufreq`.
> 
> This implementation doesn't support/implement:
> - vendor specific workarounds
> - Frequency Invariance Engine (FIE)
> - artificial Energy Model (EM)
> - (struct cpufreq_driver).attr field
> - QoS requests
> 
> Basic support is provided to get/set the frequency on a platform
> implementing the CPPC section of the ACPI spec.
> 
> Signed-off-by: Pierre Gondois <pierre.gondois@xxxxxxx>
> ---
>  drivers/cpufreq/Kconfig          |  16 ++
>  drivers/cpufreq/Makefile         |   1 +
>  drivers/cpufreq/rcppc_cpufreq.rs | 333 +++++++++++++++++++++++++++++++
>  3 files changed, 350 insertions(+)
>  create mode 100644 drivers/cpufreq/rcppc_cpufreq.rs

I'm missing why you want to re-implement an existing driver here.  Why
are you going to have 2 drivers for the same functionality/hardware?

How is the system going to handle switching between the two drivers?

thanks,

greg k-h