drm/i915: parse child device from VBT

On some laptops there is no HDMI/DP. But the xrandr still reports
several disconnected HDMI/display ports. In such case the user will be
confused.
 >DVI1 disconnected (normal left inverted right x axis y axis)
 >DP1 disconnected (normal left inverted right x axis y axis)
 >DVI2 disconnected (normal left inverted right x axis y axis)
 >DP2 disconnected (normal left inverted right x axis y axis)
 >DP3 disconnected (normal left inverted right x axis y axis)

This patch set is to use the child device parsed in VBT to decide whether
the HDMI/DP/LVDS/TV should be initialized.

Parse the child device from VBT.

The device class type is also added for LFP, TV, HDMI, DP output.

https://bugs.freedesktop.org/show_bug.cgi?id=22785

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 13ede75ff6ce..cc91cff8871c 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -545,6 +545,8 @@ typedef struct drm_i915_private {
         struct timer_list idle_timer;
         bool busy;
         u16 orig_clock;
+        int child_dev_num;
+        struct child_device_config *child_dev;
 } drm_i915_private_t;
 
 /** driver private structure attached to each drm_gem_object */