drm/i915/fbdev: add intel_fbdev_framebuffer() helper

Wrap accessing struct intel_fbdev guts in a helper.

v2: s/intel_fbdev_to_framebuffer/intel_fbdev_framebuffer/g (Ville)
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220215122957.2755529-1-jani.nikula@intel.com

drivers/gpu/drm/i915/display/intel_display_debugfs.c

@@ -16,6 +16,7 @@
 #include "intel_dp_mst.h"
 #include "intel_drrs.h"
 #include "intel_fbc.h"
+#include "intel_fbdev.h"
 #include "intel_hdcp.h"
 #include "intel_hdmi.h"
 #include "intel_pm.h"
@@ -124,9 +125,8 @@ static int i915_gem_framebuffer_info(struct seq_file *m, void *data)
 	struct drm_framebuffer *drm_fb;
 
 #ifdef CONFIG_DRM_FBDEV_EMULATION
-	if (dev_priv->fbdev && dev_priv->fbdev->helper.fb) {
-		fbdev_fb = to_intel_framebuffer(dev_priv->fbdev->helper.fb);
-
+	fbdev_fb = intel_fbdev_framebuffer(dev_priv->fbdev);
+	if (fbdev_fb) {
 		seq_printf(m, "fbcon size: %d x %d, depth %d, %d bpp, modifier 0x%llx, refcount %d, obj ",
 			   fbdev_fb->base.width,
 			   fbdev_fb->base.height,

drivers/gpu/drm/i915/display/intel_fbdev.c

@@ -680,3 +680,11 @@ void intel_fbdev_restore_mode(struct drm_device *dev)
 	if (drm_fb_helper_restore_fbdev_mode_unlocked(&ifbdev->helper) == 0)
 		intel_fbdev_invalidate(ifbdev);
 }
+
+struct intel_framebuffer *intel_fbdev_framebuffer(struct intel_fbdev *fbdev)
+{
+	if (!fbdev || !fbdev->helper.fb)
+		return NULL;
+
+	return to_intel_framebuffer(fbdev->helper.fb);
+}

drivers/gpu/drm/i915/display/intel_fbdev.h

@@ -10,6 +10,8 @@
 
 struct drm_device;
 struct drm_i915_private;
+struct intel_fbdev;
+struct intel_framebuffer;
 
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 int intel_fbdev_init(struct drm_device *dev);
@@ -19,6 +21,7 @@ void intel_fbdev_fini(struct drm_i915_private *dev_priv);
 void intel_fbdev_set_suspend(struct drm_device *dev, int state, bool synchronous);
 void intel_fbdev_output_poll_changed(struct drm_device *dev);
 void intel_fbdev_restore_mode(struct drm_device *dev);
+struct intel_framebuffer *intel_fbdev_framebuffer(struct intel_fbdev *fbdev);
 #else
 static inline int intel_fbdev_init(struct drm_device *dev)
 {
@@ -48,6 +51,10 @@ static inline void intel_fbdev_output_poll_changed(struct drm_device *dev)
 static inline void intel_fbdev_restore_mode(struct drm_device *dev)
 {
 }
+static inline struct intel_framebuffer *intel_fbdev_framebuffer(struct intel_fbdev *fbdev)
+{
+	return NULL;
+}
 #endif
 
 #endif /* __INTEL_FBDEV_H__ */