[PATCH] [RESEND] drm: fb_helper: fix CONFIG_FB dependency

[Arnd Bergmann <arnd@kernel.org>]

From: Arnd Bergmann <arnd@arndb.de>

With CONFIG_FB=m and CONFIG_DRM=y, we get a link error in the fb helper:

aarch64-linux-ld: drivers/gpu/drm/drm_fb_helper.o: in function `drm_fb_helper_alloc_fbi':
(.text+0x10cc): undefined reference to `framebuffer_alloc'

Tighten the dependency so it is only allowed in the case that DRM can
link against FB.

Fixes: f611b1e7624c ("drm: Avoid circular dependencies for CONFIG_FB")
Link: https://lore.kernel.org/all/20210721152211.2706171-1-arnd@kernel.org/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
I posted this in July, the patch is still required and should work
on its own.
---
 drivers/gpu/drm/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index cea777ae7fb9..9199f53861ca 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -103,7 +103,7 @@ config DRM_DEBUG_DP_MST_TOPOLOGY_REFS
 config DRM_FBDEV_EMULATION
 	bool "Enable legacy fbdev support for your modesetting driver"
 	depends on DRM
-	depends on FB
+	depends on FB=y || FB=DRM
 	select DRM_KMS_HELPER
 	select FB_CFB_FILLRECT
 	select FB_CFB_COPYAREA
-- 
2.29.2