drm/fb-helper: Add drm_fb_helper_defio_init()
Add helper for initializing fbdev deferred I/O.
The cleanup could have happened in drm_fb_helper_fini(), but that would
have required me to set fb_info->fbdefio to NULL in a couple of drivers
before they call _fini() to avoid double defio cleanup. The problem is
that one of those is vboxvideo which lives in Greg's staging tree.
So I put the cleanup in drm_fb_helper_fbdev_teardown(), not perfect
but not that bad either.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171215175119.36181-6-noralf@tronnes.org
diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index aa78ac3..b069433 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -276,6 +276,7 @@ void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);
void drm_fb_helper_deferred_io(struct fb_info *info,
struct list_head *pagelist);
+int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper);
ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
size_t count, loff_t *ppos);
@@ -423,6 +424,11 @@ static inline void drm_fb_helper_deferred_io(struct fb_info *info,
{
}
+static inline int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper)
+{
+ return -ENODEV;
+}
+
static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
char __user *buf, size_t count,
loff_t *ppos)