drm: Split out drm_probe_helper.c from drm_crtc_helper.c

This is leftover stuff from my previous doc round which I kinda wanted
to do but didn't yet due to rebase hell.

The modeset helpers and the probing helpers a independent and e.g.
i915 uses the probing stuff but has its own modeset infrastructure. It
hence makes to split this up. While at it add a DOC: comment for the
probing libraray.

It would be rather neat to pull some of the DocBook documenting these
two helpers into in-line DOC: comments. But unfortunately kerneldoc
doesn't support markdown or something similar to make nice-looking
documentation, so the current state is better.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>

Documentation/DocBook/drm.tmpl

@@ -2285,6 +2285,11 @@ void intel_crt_init(struct drm_device *dev)
     <sect2>
       <title>Modeset Helper Functions Reference</title>
 !Edrivers/gpu/drm/drm_crtc_helper.c
+    </sect2>
+    <sect2>
+      <title>Output Probing Helper Functions Reference</title>
+!Pdrivers/gpu/drm/drm_probe_helper.c output probing helper overview
+!Edrivers/gpu/drm/drm_probe_helper.c
     </sect2>
     <sect2>
       <title>fbdev Helper Functions Reference</title>

drivers/gpu/drm/Makefile

@@ -23,7 +23,7 @@ drm-$(CONFIG_DRM_PANEL) += drm_panel.o
 
 drm-usb-y   := drm_usb.o
 
-drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o
+drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o drm_probe_helper.o
 drm_kms_helper-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o
 drm_kms_helper-$(CONFIG_DRM_KMS_FB_HELPER) += drm_fb_helper.o
 drm_kms_helper-$(CONFIG_DRM_KMS_CMA_HELPER) += drm_fb_cma_helper.o

include/drm/drm_crtc_helper.h

@@ -125,7 +125,6 @@ struct drm_connector_helper_funcs {
 	struct drm_encoder *(*best_encoder)(struct drm_connector *connector);
 };
 
-extern int drm_helper_probe_single_connector_modes(struct drm_connector *connector, uint32_t maxX, uint32_t maxY);
 extern void drm_helper_disable_unused_functions(struct drm_device *dev);
 extern int drm_crtc_helper_set_config(struct drm_mode_set *set);
 extern bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
@@ -161,6 +160,11 @@ static inline void drm_connector_helper_add(struct drm_connector *connector,
 }
 
 extern void drm_helper_resume_force_mode(struct drm_device *dev);
+
+/* drm_probe_helper.c */
+extern int drm_helper_probe_single_connector_modes(struct drm_connector
+						   *connector, uint32_t maxX,
+						   uint32_t maxY);
 extern void drm_kms_helper_poll_init(struct drm_device *dev);
 extern void drm_kms_helper_poll_fini(struct drm_device *dev);
 extern bool drm_helper_hpd_irq_event(struct drm_device *dev);