drm: Create DEFINE_DRM_GEM_CMA_FOPS and roll it out to drivers

Less code ftw.

This converts all drivers except the tinydrm helper module. That one
needs more work, since it gets the THIS_MODULE reference from
tinydrm.ko instead of the actual driver module like it should.
Probably needs a similar trick like I used here with generating the
entire struct with a macro.

Cc: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170308141257.12119-24-daniel.vetter@ffwll.ch

include/drm/drm_gem_cma_helper.h

@@ -26,6 +26,32 @@ to_drm_gem_cma_obj(struct drm_gem_object *gem_obj)
 	return container_of(gem_obj, struct drm_gem_cma_object, base);
 }
 
+/**
+ * DEFINE_DRM_GEM_CMA_FOPS() - macro to generate file operations for CMA drivers
+ * @name: name for the generated structure
+ *
+ * This macro autogenerates a suitable &struct file_operations for CMA based
+ * drivers, which can be assigned to &drm_driver.fops. Note that this structure
+ * cannot be shared between drivers, because it contains a reference to the
+ * current module using THIS_MODULE.
+ *
+ * Note that the declaration is already marked as static - if you need a
+ * non-static version of this you're probably doing it wrong and will break the
+ * THIS_MODULE reference by accident.
+ */
+#define DEFINE_DRM_GEM_CMA_FOPS(name) \
+	static const struct file_operations name = {\
+		.owner		= THIS_MODULE,\
+		.open		= drm_open,\
+		.release	= drm_release,\
+		.unlocked_ioctl	= drm_ioctl,\
+		.compat_ioctl	= drm_compat_ioctl,\
+		.poll		= drm_poll,\
+		.read		= drm_read,\
+		.llseek		= noop_llseek,\
+		.mmap		= drm_gem_cma_mmap,\
+	}
+
 /* free GEM object */
 void drm_gem_cma_free_object(struct drm_gem_object *gem_obj);