On 15 November 2016 at 09:27, Jani Nikula <jani.nik...@linux.intel.com> wrote: > On Tue, 15 Nov 2016, David Weinehall <t...@kernel.org> wrote: >> On Mon, Nov 14, 2016 at 12:44:25PM +0200, Jani Nikula wrote: >>> On Thu, 06 Oct 2016, Tomeu Vizoso <tomeu.viz...@collabora.com> wrote: >>> > diff --git a/drivers/gpu/drm/i915/intel_display.c >>> > b/drivers/gpu/drm/i915/intel_display.c >>> > index 23a6c7213eca..7412a05fa5d9 100644 >>> > --- a/drivers/gpu/drm/i915/intel_display.c >>> > +++ b/drivers/gpu/drm/i915/intel_display.c >>> > @@ -14636,6 +14636,7 @@ static const struct drm_crtc_funcs >>> > intel_crtc_funcs = { >>> > .page_flip = intel_crtc_page_flip, >>> > .atomic_duplicate_state = intel_crtc_duplicate_state, >>> > .atomic_destroy_state = intel_crtc_destroy_state, >>> > + .set_crc_source = intel_crtc_set_crc_source, >>> > }; >>> > >>> > /** >>> > diff --git a/drivers/gpu/drm/i915/intel_drv.h >>> > b/drivers/gpu/drm/i915/intel_drv.h >>> > index 737261b09110..31894b7c6517 100644 >>> > --- a/drivers/gpu/drm/i915/intel_drv.h >>> > +++ b/drivers/gpu/drm/i915/intel_drv.h >>> > @@ -1844,6 +1844,14 @@ void intel_color_load_luts(struct drm_crtc_state >>> > *crtc_state); >>> > /* intel_pipe_crc.c */ >>> > int intel_pipe_crc_create(struct drm_minor *minor); >>> > void intel_pipe_crc_cleanup(struct drm_minor *minor); >>> > +#ifdef CONFIG_DEBUG_FS >>> > +int intel_crtc_set_crc_source(struct drm_crtc *crtc, const char >>> > *source_name, >>> > + size_t *values_cnt); >>> > +#else >>> > +static inline int intel_crtc_set_crc_source(struct drm_crtc *crtc, >>> > + const char *source_name, >>> > + size_t *values_cnt) { return 0; } >>> > +#endif >>> >>> "inline" here doesn't work because it's used as a function pointer. >>> >>> Is it better to have a function that returns 0 for .set_crc_source, or >>> to set .set_crc_source to NULL when CONFIG_DEBUG_FS=n? >> >> I'd say that whenever we have a function pointer we should have a dummy >> function without side-effects for this kind of things. > > Whoever calls .set_crc_source could do smarter things depending on the > hook not being there vs. just silently plunging on.
In this specific case, when CONFIG_DEBUG_FS=n it doesn't make any sense to call that callback, so I think we should have a dummy implementation to avoid adding an ifdef to the .c. Regards, Tomeu _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx