drm: Add drm_device->fb_helper pointer

drm_fb_helper is *the* way of doing fbdev emulation so add a pointer to
struct drm_device. This makes it possible to add callback helpers for
.last_close and .output_poll_changed further reducing fbdev emulation
footprint in drivers. The pointer is set by drm_fb_helper_init() and
cleared by drm_fb_helper_fini().

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171030153951.56269-3-noralf@tronnes.org

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 954cdd4..19aaca9 100644 (file)
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -799,8 +799,10 @@ int drm_fb_helper_init(struct drm_device *dev,
        struct drm_mode_config *config = &dev->mode_config;
        int i;
 
-       if (!drm_fbdev_emulation)
+       if (!drm_fbdev_emulation) {
+               dev->fb_helper = fb_helper;
                return 0;
+       }
 
        if (!max_conn_count)
                return -EINVAL;
@@ -835,6 +837,8 @@ int drm_fb_helper_init(struct drm_device *dev,
                i++;
        }
 
+       dev->fb_helper = fb_helper;
+
        return 0;
 out_free:
        drm_fb_helper_crtc_free(fb_helper);
@@ -913,7 +917,12 @@ void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 {
        struct fb_info *info;
 
-       if (!drm_fbdev_emulation || !fb_helper)
+       if (!fb_helper)
+               return;
+
+       fb_helper->dev->fb_helper = NULL;
+
+       if (!drm_fbdev_emulation)
                return;
 
        cancel_work_sync(&fb_helper->resume_work);

diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
index e21af87..7c4fa32 100644 (file)
--- a/include/drm/drm_device.h
+++ b/include/drm/drm_device.h
@@ -17,6 +17,7 @@ struct drm_vblank_crtc;
 struct drm_sg_mem;
 struct drm_local_map;
 struct drm_vma_offset_manager;
+struct drm_fb_helper;
 
 struct inode;
 
@@ -185,6 +186,14 @@ struct drm_device {
        struct drm_vma_offset_manager *vma_offset_manager;
        /*@} */
        int switch_power_state;
+
+       /**
+        * @fb_helper:
+        *
+        * Pointer to the fbdev emulation structure.
+        * Set by drm_fb_helper_init() and cleared by drm_fb_helper_fini().
+        */
+       struct drm_fb_helper *fb_helper;
 };
 
 #endif