drm/i915: Add audio pin sense / ELD callback

This callback will be called by the i915 driver to notify the hda
driver that its HDMI information needs to be refreshed, i e,
that audio output is now available (or unavailable) - usually as a
result of a monitor being plugged in (or unplugged).
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/drm/i915_component.h

@@ -34,6 +34,18 @@ struct i915_audio_component {
 		void (*codec_wake_override)(struct device *, bool enable);
 		int (*get_cdclk_freq)(struct device *);
 	} *ops;
+
+	const struct i915_audio_component_audio_ops {
+		void *audio_ptr;
+		/**
+		 * Call from i915 driver, notifying the HDA driver that
+		 * pin sense and/or ELD information has changed.
+		 * @audio_ptr:		HDA driver object
+		 * @port:		Which port has changed (PORTA / PORTB / PORTC etc)
+		 * @port_mst_index:	Index within that port, for DisplayPort multistreaming
+		 */
+		void (*pin_eld_notify)(void *audio_ptr, int port, int port_mst_index);
+	} *audio_ops;
 };
 
 #endif /* _I915_COMPONENT_H_ */