drm/i915: Use FLISDSI interface for band gap reset

v2: Rebased on latest code

Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
Signed-off-by: Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
Reviewed-by: Jani Nikula<jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index a3804b2..709b20e 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2475,6 +2475,8 @@
 		   enum intel_sbi_destination destination);
 void intel_sbi_write(struct drm_i915_private *dev_priv, u16 reg, u32 value,
 		     enum intel_sbi_destination destination);
+u32 vlv_flisdsi_read(struct drm_i915_private *dev_priv, u32 reg);
+void vlv_flisdsi_write(struct drm_i915_private *dev_priv, u32 reg, u32 val);
 
 int vlv_gpu_freq(struct drm_i915_private *dev_priv, int val);
 int vlv_freq_opcode(struct drm_i915_private *dev_priv, int val);