iosys-map: Add IOSYS_MAP_INIT_VADDR_IOMEM()

Add IOSYS_MAP_INIT_VADDR_IOMEM() for static init of variables of type
struct iosys_map.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220808125406.20752-2-tzimmermann@suse.de

include/linux/iosys-map.h

@@ -46,10 +46,13 @@
  *
  *	iosys_map_set_vaddr(&map, 0xdeadbeaf);
  *
- * To set an address in I/O memory, use iosys_map_set_vaddr_iomem().
+ * To set an address in I/O memory, use IOSYS_MAP_INIT_VADDR_IOMEM() or
+ * iosys_map_set_vaddr_iomem().
  *
  * .. code-block:: c
  *
+ *	struct iosys_map map = IOSYS_MAP_INIT_VADDR_IOMEM(0xdeadbeaf);
+ *
  *	iosys_map_set_vaddr_iomem(&map, 0xdeadbeaf);
  *
  * Instances of struct iosys_map do not have to be cleaned up, but
@@ -121,6 +124,16 @@ struct iosys_map {
 		.is_iomem = false,	\
 	}
 
+/**
+ * IOSYS_MAP_INIT_VADDR_IOMEM - Initializes struct iosys_map to an address in I/O memory
+ * @vaddr_iomem_:	An I/O-memory address
+ */
+#define IOSYS_MAP_INIT_VADDR_IOMEM(vaddr_iomem_)	\
+	{						\
+		.vaddr_iomem = (vaddr_iomem_),		\
+		.is_iomem = true,			\
+	}
+
 /**
  * IOSYS_MAP_INIT_OFFSET - Initializes struct iosys_map from another iosys_map
  * @map_:	The dma-buf mapping structure to copy from