[PATCH] drm/vc4: Allow fb modifiers early enough to fill IN_FORMATS property

[Paul Kocialkowski]

The KMS mode_config elements are currently configured in vc4_kms_load,
that is called after all components are binded (component_bind_all).
However, the CRTC component (for the Pixel Valve) needs to access the
allow_fb_modifiers element at bind time, when initializing its planes
through drm_universal_plane_init.

This helpers checks allow_fb_modifiers to decide whether to fill the
IN_FORMATS property. Because allow_fb_modifiers is still set to false
at this point, the property is never filled and userspace cannot
retrieve the combination of supported formats and modifiers.

Fix this by setting allow_fb_modifiers right after calling
drm_mode_config_init (which initializes the structure), before binding
the components of the driver.

Fixes: 423ad7b3cbd1 ("drm/vc4: Advertise supported modifiers for planes")
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx>
---
 drivers/gpu/drm/vc4/vc4_drv.c | 1 +
 drivers/gpu/drm/vc4/vc4_kms.c | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index 7195a0bcceb3..5c24f80dd34e 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -273,6 +273,7 @@ static int vc4_drm_bind(struct device *dev)
 		goto dev_put;
 
 	drm_mode_config_init(drm);
+	drm->mode_config.allow_fb_modifiers = true;
 
 	vc4_gem_init(drm);
 
diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c
index b0cbb869f659..b70931fd8cf0 100644
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -530,7 +530,6 @@ int vc4_kms_load(struct drm_device *dev)
 	dev->mode_config.funcs = &vc4_mode_funcs;
 	dev->mode_config.preferred_depth = 24;
 	dev->mode_config.async_page_flip = true;
-	dev->mode_config.allow_fb_modifiers = true;
 
 	drm_modeset_lock_init(&vc4->ctm_state_lock);
 
-- 
2.20.1