drm/i915: restore only the mode of this driver on lastclose (v2)

i915 calls the panic handler function on last close to reset the modes,
however this is a really bad idea for multi-gpu machines, esp shareable
gpus machines. So add a new entry point for the driver to just restore
its own fbcon mode.

v2: move code into fb helper, fix panic code to block mode change on
powered off GPUs.

[airlied: this hits drm core and I wrote it and it was reviewed on intel-gfx
 so really I signed it off twice ;-).]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index f22e7fe4b6db..ade09d7b4271 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -118,6 +118,7 @@ int drm_fb_helper_setcolreg(unsigned regno,
                             unsigned transp,
                             struct fb_info *info);
 
+bool drm_fb_helper_restore_fbdev_mode(struct drm_fb_helper *fb_helper);
 void drm_fb_helper_restore(void);
 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
                             uint32_t fb_width, uint32_t fb_height);