Re: [PATCH 2/4] soc: qcom: aoss: Add debugfs interface for sending messages

[Bjorn Andersson]

On Mon, Jul 31, 2023 at 10:21:31AM +0200, Andrew Lunn wrote:
> On Sun, Jul 30, 2023 at 09:10:11PM -0700, Bjorn Andersson wrote:
> > From: Chris Lew <clew@xxxxxxxxxxxxxx>
> > 
> > In addition to the normal runtime commands, the Always On Processor
> > (AOP) provides a number of debug commands which can be used during
> > system debugging for things such as preventing power collapse or placing
> > floor votes for certain resources. Some of these are documented in the
> > Robotics RB5 "Debug AOP ADB" linked below.
> > 
> > Provide a debugfs interface for the developer/tester to send these
> > commands to the AOP.
> 
> This sort of sending arbitrary binary blob commands is not liked,
> since it allow user space closed source drivers. At minimum, please
> provide a file per command, with the kernel marshalling parameters
> into the binary format, and decoding any returned values.
> 

Thanks for your input Andrew, that is a valid concern.

The interface is in debugfs and as such wouldn't be suitable for closed
source drivers, as in the majority of our shipping software debugfs
isn't enabled.

Regards,
Bjorn