Re: [PATCH 2/3] mfd: intel_soc_pmic: Rename pwm_backlight pwm-lookup to pwm_pmic_backlight

Lee Jones
2019-12-12T08:46:01Z

On Wed, 11 Dec 2019, Hans de Goede wrote:

> Hi Lee,
>
> On 10-12-2019 09:51, Lee Jones wrote:
> > On Tue, 19 Nov 2019, Hans de Goede wrote:
> >
> > > At least Bay Trail (BYT) and Cherry Trail (CHT) devices can use 1 of 2
> > > different PWM controllers for controlling the LCD's backlight brightness.
> > >
> > > Either the one integrated into the PMIC or the one integrated into the
> > > SoC (the 1st LPSS PWM controller).
> > >
> > > So far in the LPSS code on BYT we have skipped registering the LPSS PWM
> > > controller "pwm_backlight" lookup entry when a Crystal Cove PMIC is
> > > present, assuming that in this case the PMIC PWM controller will be used.
> > >
> > > On CHT we have been relying on only 1 of the 2 PWM controllers being
> > > enabled in the DSDT at the same time; and always registered the lookup.
> > >
> > > So far this has been working, but the correct way to determine which PWM
> > > controller needs to be used is by checking a bit in the VBT table and
> > > recently I've learned about 2 different BYT devices:
> > > Point of View MOBII TAB-P800W
> > > Acer Switch 10 SW5-012
> > >
> > > Which use a Crystal Cove PMIC, yet the LCD is connected to the SoC/LPSS
> > > PWM controller (and the VBT correctly indicates this), so here our old
> > > heuristics fail.
> > >
> > > Since only the i915 driver has access to the VBT, this commit renames
> > > the "pwm_backlight" lookup entries for the Crystal Cove PMIC's PWM
> > > controller to "pwm_pmic_backlight" so that the i915 driver can do a
> > > pwm_get() for the right controller depending on the VBT bit, instead of
> > > the i915 driver relying on a "pwm_backlight" lookup getting registered
> > > which magically points to the right controller.
> > >
> > > Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> > > ---
> > > drivers/mfd/intel_soc_pmic_core.c | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > For my own reference:
> > Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>
>
> As mentioned in the cover-letter, to avoid breaking bi-sectability
> as well as to avoid breaking the intel-gfx CI we need to merge this series
> in one go through one tree. Specifically through the drm-intel tree.
> Is that ok with you ?
>
> If this is ok with you, then you do not have to do anything, I will just push
> the entire series to drm-intel. drivers/mfd/intel_soc_pmic_core.c
> does not see much changes so I do not expect this to lead to any conflicts.

It's fine, so long as a minimal immutable pull-request is provided.
Whether it's pulled or not will depend on a number of factors, but it
needs to be an option.

--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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