[PATCH 05/10] edid-decode: output timings for YCbCr 4:2:0 cmdb

[joevt <joevt@xxxxxxx>]

- "YCbCr 4:2:0 capability map data block" now outputs the modes that support YCbCr 4:2:0 instead of just indexes of the modes. Indexes refer to timings in "Video Data Block".
- Warnings are included in the output if "Video Data Block" doesn't appear before "YCbCr 4:2:0 Capability Map Data Block" or if the index is outside the range defined in the "Video Data Block".
- Moved inner loop of cta_svd into a new function cta_svd_one so that it can be reused by cta_y420cmdb.

Signed-off-by: Joe van Tunen <joevt@xxxxxxx>
---
 edid-decode.c | 44 +++++++++++++++++++++++++++++++++++---------
 1 file changed, 35 insertions(+), 9 deletions(-)

diff --git a/edid-decode.c b/edid-decode.c
index b833178..4d6fe29 100644
--- a/edid-decode.c
+++ b/edid-decode.c
@@ -1454,13 +1454,10 @@ static const struct edid_cta_mode *vic_to_mode(unsigned char vic)
 	return NULL;
 }
 
-static void cta_svd(const unsigned char *x, unsigned n, int for_ycbcr420)
+static void cta_svd_one(const unsigned char *x, int for_ycbcr420)
 {
-	unsigned i;
-
-	for (i = 0; i < n; i++)  {
 		const struct edid_cta_mode *vicmode = NULL;
-		unsigned char svd = x[i];
+		unsigned char svd = x[0];
 		unsigned char native;
 		unsigned char vic;
 		const char *mode;
@@ -1468,7 +1465,7 @@ static void cta_svd(const unsigned char *x, unsigned n, int for_ycbcr420)
 		unsigned clock_khz = 0;
 
 		if ((svd & 0x7f) == 0)
-			continue;
+			return;
 
 		if ((svd - 1) & 0x40) {
 			vic = svd;
@@ -1511,10 +1508,23 @@ static void cta_svd(const unsigned char *x, unsigned n, int for_ycbcr420)
 		if (vic == 1)
 			has_cta861_vic_1 = 1;
 	}
+
+static void cta_svd(const unsigned char *x, int n, int for_ycbcr420)
+{
+	for (unsigned i = 0; i < n; i++)  {
+		printf("    ");
+		cta_svd_one(x+i, for_ycbcr420);
+		printf("\n");
+	}
 }
 
+unsigned const char *last_cta_video_block_start = NULL;
+unsigned last_cta_video_block_length = 0;
+
 static void cta_video_block(const unsigned char *x, unsigned length)
 {
+	last_cta_video_block_start = x;
+	last_cta_video_block_length = length;
 	cta_svd(x, length, 0);
 }
 
@@ -1531,9 +1541,25 @@ static void cta_y420cmdb(const unsigned char *x, unsigned length)
 		uint8_t v = x[0 + i];
 		unsigned j;
 
-		for (j = 0; j < 8; j++)
-			if (v & (1 << j))
-				printf("    VSD Index %u\n", i * 8 + j);
+		for (j = 0; j < 8; j++) {
+			if (v & (1 << j)) {
+				unsigned k = i * 8 + j;
+				printf("    VSD Index %u", k + 1);
+				if (k >= last_cta_video_block_length) {
+					if (last_cta_video_block_start) {
+						printf(" (out of range)");
+					} else {
+						printf(" (missing CTA video block)");
+					}
+				}
+				else
+				{
+					printf(" ");
+					cta_svd_one(last_cta_video_block_start+k, 0);
+				}
+				printf("\n");
+			}
+		}
 	}
 }
 
-- 
2.21.0 (Apple Git-122.2)