[0/4] clk: debugfs: add some simple debug functionality

Message

Tero Kristo Oct. 1, 2019, 9:01 a.m. UTC

Hi,

I have been using a variation of these patches myself for several years
for debugging / testing different clock issues. Basically what I do here
is extend the functionality of debugfs to allow write access to certain
properties, like rate, enable / prepare counts, mux parents.

This allows simple testing of new features or debugging directly from
userspace. The functionality is hidden behind a Kconfig option because
it can be rather dangerous to allow access to these unconditionally if
the user does not know what they are doing.

Any thoughts?

-Tero


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Comments

Tomi Valkeinen Oct. 1, 2019, 9:21 a.m. UTC | #1

On 01/10/2019 12:01, Tero Kristo wrote:
> Hi,
> 
> I have been using a variation of these patches myself for several years
> for debugging / testing different clock issues. Basically what I do here
> is extend the functionality of debugfs to allow write access to certain
> properties, like rate, enable / prepare counts, mux parents.
> 
> This allows simple testing of new features or debugging directly from
> userspace. The functionality is hidden behind a Kconfig option because
> it can be rather dangerous to allow access to these unconditionally if
> the user does not know what they are doing.
> 
> Any thoughts?

I haven't reviewed the patches, but I've been using (earlier versions 
of) these, and at least for me they were of great value finding clock 
related issues.

So what it's worth, +1 from me.

  Tomi

Stephen Boyd Jan. 6, 2020, 3:13 a.m. UTC | #2

Quoting Tero Kristo (2019-10-01 02:01:58)
> Hi,
> 
> I have been using a variation of these patches myself for several years
> for debugging / testing different clock issues. Basically what I do here
> is extend the functionality of debugfs to allow write access to certain
> properties, like rate, enable / prepare counts, mux parents.
> 
> This allows simple testing of new features or debugging directly from
> userspace. The functionality is hidden behind a Kconfig option because
> it can be rather dangerous to allow access to these unconditionally if
> the user does not know what they are doing.
> 
> Any thoughts?

I just applied Geerts approach to this. Let's follow that and not
provide any Kconfig things.