Re: [GIT PULL] Thermal management updates for v4.17-rc1

[Bartlomiej Zolnierkiewicz]

On Friday, April 13, 2018 11:00:43 AM Daniel Lezcano wrote:
> On 13/04/2018 10:55, Bartlomiej Zolnierkiewicz wrote:
> > On Friday, April 13, 2018 01:39:05 PM Zhang Rui wrote:
> >> Hi, Eduardo,
> >>
> >> On å, 2018-04-12 at 21:08 -0700, Eduardo Valentin wrote:
> >>> Hello,
> >>>
> >>> On Thu, Apr 12, 2018 at 09:55:19AM -0700, Linus Torvalds wrote:
> >>>>
> >>>> On Wed, Apr 11, 2018 at 10:08 PM, Zhang Rui <rui.zhang@xxxxxxxxx>
> >>>> wrote:
> >>>>>
> >>>>>
> >>>>> could you please illustrate me what the kconfig & warning is?
> >>>> Just "make allmodconfig" and the warning is about a uninitialized
> >>>> variable.
> >>>>
> >>>> Line 304 in drivers/thermal/samsung/exynos_tmu.c if my shell
> >>>> history
> >>>> is to be believed.
> >>>>
> >>>>                 Linus
> >>> Yeah, this has also passed my local compilation error. Somehow my
> >>> gcc4.9
> >>> is not catching it. Using an older gcc (gcc4.6) does catch it.
> >>>
> >>> Anyways, given that the conversion functions are written to cover
> >>> for unexpected cal_type, the right way of fixing this is to rewrite
> >>> the conversion functions to allow for returning error codes and
> >>> adjusting the callers as expected.
> >>>
> >>> Rui, bzolnier, please consider the following fix:
> >>>
> >> as it is late in this merge window, I'd prefer to
> >> 1. drop all the thermal-soc material in the first pull request which I
> >> will send out soon.
> >> 2. you can prepare another pull request containing the thermal-soc
> >> materials except the exynos fixes
> >> 3. exynos fixes with the problem solved can be queued for -rc2 or
> >> later.
> > 
> > Could you please just merge the obvious fix from Arnd instead?
> > 
> > [ it was posted two weeks ago and ACKed by me ]
> > 
> > https://patchwork.kernel.org/patch/10313313/
> 
> I'm not sure these are correct fixes.
> 
> The change 480b5bfc16e1 tells:
> 
> "There should be no functional changes caused by this patch."
> 
> but the fix above returns 0 as a default value instead of '50' or '25'
> for the 5440 and that impacts the threshold etc ...
> 
> IMO, the correct fix would be to define a default value '50', override
> it at init time to '25' if it is a 5440. And then the variable 'temp'
> and 'temp_code' get this value in the default case.

It is okay to return 0 because this code-path (the default one) will be
never hit by the driver (probe makes sure of it) - the default case is
here is just to silence compilation errors..

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics