On Mon, Feb 26, 2018 at 10:21 AM, Maxime Ripard <maxime.ripard@xxxxxxxxxxx> wrote: > Hi, > > On Fri, Feb 23, 2018 at 02:06:52PM +0100, Arnd Bergmann wrote: >> When the base sun4i DRM driver is built-in but the back-end is >> a loadable module, we run into a link error: >> >> drivers/gpu/drm/sun4i/sun4i_drv.o: In function `sun4i_drv_probe': >> sun4i_drv.c:(.text+0x60c): undefined reference to `sun4i_frontend_of_table' >> >> The dependency is a bit tricky, the best workaround I have come up >> with is to use a Makefile hack to to interpret both >> CONFIG_DRM_SUN4I_BACKEND=m and CONFIG_DRM_SUN4I_BACKEND=y >> as a directive to build the front-end the same way as the main module. >> >> Fixes: dd0421f47505 ("drm/sun4i: Add a driver for the display frontend") >> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> >> --- >> drivers/gpu/drm/sun4i/Makefile | 5 ++++- >> 1 file changed, 4 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/sun4i/Makefile b/drivers/gpu/drm/sun4i/Makefile >> index 582607c0c488..db14e023256b 100644 >> --- a/drivers/gpu/drm/sun4i/Makefile >> +++ b/drivers/gpu/drm/sun4i/Makefile >> @@ -25,6 +25,9 @@ obj-$(CONFIG_DRM_SUN4I) += sun4i-tcon.o >> obj-$(CONFIG_DRM_SUN4I) += sun4i_tv.o >> obj-$(CONFIG_DRM_SUN4I) += sun6i_drc.o >> >> -obj-$(CONFIG_DRM_SUN4I_BACKEND) += sun4i-backend.o sun4i-frontend.o >> +obj-$(CONFIG_DRM_SUN4I_BACKEND) += sun4i-backend.o >> +ifdef CONFIG_DRM_SUN4I_BACKEND >> +obj-$(CONFIG_DRM_SUN4I) += sun4i-frontend.o >> +endif > > Can we just create a Kconfig symbol, selected by DRM_SUN4I_BACKEND, > and we would export the symbol? Yes, I think that would work just as well. Something like config DRM_SUN4I_FRONTEND tristate default DRM_SUN4I if CONFIG_DRM_SUN4I_BACKEND != n should do the trick. Arnd _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel