dg
On Mon, Apr 24, 2017 at 07:39:27PM +0200, Arnd Bergmann wrote:
> On Mon, Apr 24, 2017 at 12:44 PM, Lucas Stach <l.stach@pengutronix.de> wrote:
> > Am Mittwoch, den 19.04.2017, 20:11 +0200 schrieb Arnd Bergmann:
> >> When CONFIG_THERMAL is enabled as a loadable module, and etnaviv is
> >> built-in, we get a link error:
> >>
> >> drivers/gpu/drm/etnaviv/etnaviv_gpu.o: In function `etnaviv_gpu_bind':
> >> etnaviv_gpu.c:(.text.etnaviv_gpu_bind+0x34): undefined reference to `thermal_of_cooling_device_register'
> >> etnaviv_gpu.c:(.text.etnaviv_gpu_bind+0xe0): undefined reference to `thermal_cooling_device_unregister'
> >> drivers/gpu/drm/etnaviv/etnaviv_gpu.o: In function `etnaviv_gpu_unbind':
> >> etnaviv_gpu.c:(.text.etnaviv_gpu_unbind+0xf0): undefined reference to `thermal_cooling_device_unregister'
> >>
> >> This adds a Kconfig dependency to prevent etnaviv from being built-in
> >> with CONFIG_THERMAL=m, while still allowing the valid configurations.
> >> Unfortunately, simply adding the dependency here breaks Kconfig through
> >> a dependency loop involving lots of symbols all the way until ACPI_VIDEO,
> >> which is the only video driver that explicitly selects 'THERMAL'. Turning
> >> this into a 'depends on' addresses the problem.
> >> For completeness, I'm also removing the redundant 'select THERMAL'
> >> from INTEL_MENLOW, so no other driver uses that statement.
> >>
> >> Fixes: bcdfb5e56dc5 ("drm/etnaviv: add etnaviv cooling device")
> >> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> >
> > This patch mixes a few things, so the subject doesn't really fit. I'm
> > fine with taking the patch trough my tree, if I can get an ACK on the
> > ACPI part.
> 
> Actually the ACPI part triggered a new warning that I haven't figured
> out completely yet. Please disregard my patch for the moment.
> 
> I think we can just drop the dependency in ACPI_VIDEO, but I'm not
> entirely sure yet if we could hit a broken configuration with THERMAL=m
> and ACPI_VIDEO=y in that case. Unfortunately we cannot use the
> same trick in ACPI_VIDEO that I used for ETNAVIV, because of
> another circular dependency in ACPI.
> 
>         Arnd