drm: Rely on mode_config data for fb_helper initialization

Instead of receiving the num_crts as a parameter, we can read it
directly from the mode_config structure.  I audited the drivers that
invoke this helper and I believe all of them initialize the mode_config
struct accordingly, prior to calling the fb_helper.

I used the following coccinelle hack to make this transformation, except
for the function headers and comment updates.  The first and second
rules are split because I couldn't find a way to remove the unused
temporary variables at the same time I removed the parameter.

// <smpl>
@r@
expression A,B,D,E;
identifier C;
@@
(
- drm_fb_helper_init(A,B,C,D)
+ drm_fb_helper_init(A,B,D)
|
- drm_fbdev_cma_init_with_funcs(A,B,C,D,E)
+ drm_fbdev_cma_init_with_funcs(A,B,D,E)
|
- drm_fbdev_cma_init(A,B,C,D)
+ drm_fbdev_cma_init(A,B,D)
)

@@
expression A,B,C,D,E;
@@
(
- drm_fb_helper_init(A,B,C,D)
+ drm_fb_helper_init(A,B,D)
|
- drm_fbdev_cma_init_with_funcs(A,B,C,D,E)
+ drm_fbdev_cma_init_with_funcs(A,B,D,E)
|
- drm_fbdev_cma_init(A,B,C,D)
+ drm_fbdev_cma_init(A,B,D)
)

@@
identifier r.C;
type T;
expression V;
@@
- T C;
<...
when != C
- C = V;
...>
// </smpl>

Changes since v1:
 - Rebased on top of the tip of drm-misc-next.
 - Remove mention to sti since a proper fix got merged.

Suggested-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170202162640.27261-1-krisman@collabora.co.uk

1 files changed, 0 insertions, 1 deletions

diff --git a/drivers/gpu/drm/qxl/qxl_fb.c b/drivers/gpu/drm/qxl/qxl_fb.c
index 53edfa498af5..d479b7a7abe4 100644
--- a/drivers/gpu/drm/qxl/qxl_fb.c
+++ b/drivers/gpu/drm/qxl/qxl_fb.c
@@ -399,7 +399,6 @@ int qxl_fbdev_init(struct qxl_device *qdev)
 			      &qxl_fb_helper_funcs);
 
 	ret = drm_fb_helper_init(&qdev->ddev, &qfbdev->helper,
-				 qxl_num_crtc,
 				 QXLFB_CONN_LIMIT);
 	if (ret)
 		goto free;