ASoC: SDCA: Add flag for unused IRQs

Zero is a valid SDCA IRQ interrupt position so add a special value to
indicate that the IRQ is not used.

Reviewed-by: Bard Liao <[email protected]>
Signed-off-by: Charles Keepax <[email protected]>
Reviewed-by: Pierre-Louis Bossart <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>

Author: charleskeepax

include/sound/sdca_function.h

@@ -17,6 +17,8 @@ struct device;
 struct sdca_entity;
 struct sdca_function_desc;
 
+#define SDCA_NO_INTERRUPT -1
+
 /*
  * The addressing space for SDCA relies on 7 bits for Entities, so a
  * maximum of 128 Entities per function can be represented.

sound/soc/sdca/sdca_functions.c

@@ -912,6 +912,8 @@ static int find_sdca_entity_control(struct device *dev, struct sdca_entity *enti
 				       &tmp);
 	if (!ret)
 		control->interrupt_position = tmp;
+	else
+		control->interrupt_position = SDCA_NO_INTERRUPT;
 
 	control->label = find_sdca_control_label(dev, entity, control);
 	if (!control->label)