Re: [PATCH] drm/tegra: mark t186 display hub PM functions __maybe_unused

From: Thierry Reding
Date: Fri Dec 15 2017 - 08:33:52 EST


On Fri, Dec 15, 2017 at 01:51:52PM +0100, Arnd Bergmann wrote:
> The newly introduced driver has optional suspend/resume functions,
> causing a warning when CONFIG_PM is disabled:
>
> drivers/gpu/drm/tegra/hub.c:749:12: error: 'tegra_display_hub_resume' defined but not used [-Werror=unused-function]
> drivers/gpu/drm/tegra/hub.c:733:12: error: 'tegra_display_hub_suspend' defined but not used [-Werror=unused-function]
>
> This marks them __maybe_unused to shut up the warnings.
>
> Fixes: c4755fb9064f ("drm/tegra: Add Tegra186 display hub support")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> drivers/gpu/drm/tegra/hub.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)

We had touched on this topic in a different thread. The Tegra DRM driver
currently relies on runtime PM to work properly. I don't see a reason to
not make that official by adding a select PM to menuconfig ARCH_TEGRA on
32-bit ARM just like we already do on 64-bit ARM.

I've gone and applied this patch as an interim solution. Once we've made
the switch to select PM on all generations of Tegra we can remove all
the #ifdef and __maybe_unused.

Thanks,
Thierry

Attachment: signature.asc
Description: PGP signature