[media] V4L: soc-camera: avoid huge arrays, caused by changed format codes

Recently mediabus pixel format codes have become a part of the user-
space API, at which time their values also have been changed from
contiguous numbers, running from 0 to sparse numbers with values
around 0x1000, 0x2000, 0x3000... This made them unsuitable for the
use as array indices. This patch switches soc-camera internal format
look-ups to not depend on values of those macros.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/soc_mediabus.h b/include/media/soc_mediabus.h
index 3b5a70b..3eed98e 100644
--- a/include/media/soc_mediabus.h
+++ b/include/media/soc_mediabus.h
@@ -58,6 +58,20 @@
 	u8			bits_per_sample;
 };
 
+/**
+ * struct soc_mbus_lookup - Lookup FOURCC IDs by mediabus codes for pass-through
+ * @code:	mediabus pixel-code
+ * @fmt:	pixel format description
+ */
+struct soc_mbus_lookup {
+	enum v4l2_mbus_pixelcode	code;
+	struct soc_mbus_pixelfmt	fmt;
+};
+
+const struct soc_mbus_pixelfmt *soc_mbus_find_fmtdesc(
+	enum v4l2_mbus_pixelcode code,
+	const struct soc_mbus_lookup *lookup,
+	int n);
 const struct soc_mbus_pixelfmt *soc_mbus_get_fmtdesc(
 	enum v4l2_mbus_pixelcode code);
 s32 soc_mbus_bytes_per_line(u32 width, const struct soc_mbus_pixelfmt *mf);