On Tue, Mar 15, 2022 at 09:45:59AM +0100, Thomas Zimmermann wrote:
Fix a number of undefined references to drm_kms_helper.ko in drm_dp_helper.ko:
arm-suse-linux-gnueabi-ld: drivers/gpu/drm/dp/drm_dp_mst_topology.o: in function `drm_dp_mst_duplicate_state': drm_dp_mst_topology.c:(.text+0x2df0): undefined reference to `__drm_atomic_helper_private_obj_duplicate_state' arm-suse-linux-gnueabi-ld: drivers/gpu/drm/dp/drm_dp_mst_topology.o: in function `drm_dp_delayed_destroy_work': drm_dp_mst_topology.c:(.text+0x370c): undefined reference to `drm_kms_helper_hotplug_event' arm-suse-linux-gnueabi-ld: drivers/gpu/drm/dp/drm_dp_mst_topology.o: in function `drm_dp_mst_up_req_work': drm_dp_mst_topology.c:(.text+0x7938): undefined reference to `drm_kms_helper_hotplug_event' arm-suse-linux-gnueabi-ld: drivers/gpu/drm/dp/drm_dp_mst_topology.o: in function `drm_dp_mst_link_probe_work': drm_dp_mst_topology.c:(.text+0x82e0): undefined reference to `drm_kms_helper_hotplug_event'
This happens if panel-edp.ko has been configured with
DRM_PANEL_EDP=y DRM_DP_HELPER=y DRM_KMS_HELPER=m
which builds DP helpers into the kernel and KMS helpers sa a module. Making DRM_PANEL_EDP select DRM_KMS_HELPER resolves this problem.
To avoid a resulting cyclic dependency with DRM_PANEL_BRIDGE, don't make the latter depend on DRM_KMS_HELPER and fix the one DRM bridge drivers that doesn't already select DRM_KMS_HELPER. As KMS helpers cannot be selected directly by the user, config symbols should avoid depending on it anyway.
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Fixes: 3755d35ee1d2 ("drm/panel: Select DRM_DP_HELPER for DRM_PANEL_EDP") Reported-by: kernel test robot lkp@intel.com Cc: Thomas Zimmermann tzimmermann@suse.de Cc: Naresh Kamboju naresh.kamboju@linaro.org Cc: Linux Kernel Functional Testing lkft@linaro.org Cc: Lyude Paul lyude@redhat.com Cc: Sam Ravnborg sam@ravnborg.org Cc: Daniel Vetter daniel@ffwll.ch Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Maxime Ripard mripard@kernel.org Cc: dri-devel@lists.freedesktop.org Cc: Dave Airlie airlied@redhat.com Cc: Thierry Reding thierry.reding@gmail.com
This patch fixes the build error that I see with qcom_defconfig in linux-next.
Tested-by: Brian Masney bmasney@redhat.com