media: coda: extend GOP size range

CodaDx6 only accepts GOP sizes up to 60 frames, but CODA960 can handle
up to 99 frames. If we disable automatic I frame generation altogether
by setting GOP size to 0, we can let an application produce arbitrarily
large I frame intervals using the V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME
control.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/coda/coda-bit.c

@@ -1006,7 +1006,7 @@ static int coda_start_encoding(struct coda_ctx *ctx)
 			break;
 		}
 		coda_write(dev, value, CODA_CMD_ENC_SEQ_SLICE_MODE);
-		value = ctx->params.gop_size & CODA_GOP_SIZE_MASK;
+		value = ctx->params.gop_size;
 		coda_write(dev, value, CODA_CMD_ENC_SEQ_GOP_SIZE);
 	}
 
@@ -1250,7 +1250,8 @@ static int coda_prepare_encode(struct coda_ctx *ctx)
 	force_ipicture = ctx->params.force_ipicture;
 	if (force_ipicture)
 		ctx->params.force_ipicture = false;
-	else if ((src_buf->sequence % ctx->params.gop_size) == 0)
+	else if (ctx->params.gop_size != 0 &&
+		 (src_buf->sequence % ctx->params.gop_size) == 0)
 		force_ipicture = 1;
 
 	/*

drivers/media/platform/coda/coda-common.c

@@ -1746,10 +1746,12 @@ static const struct v4l2_ctrl_ops coda_ctrl_ops = {
 
 static void coda_encode_ctrls(struct coda_ctx *ctx)
 {
+	int max_gop_size = (ctx->dev->devtype->product == CODA_DX6) ? 60 : 99;
+
 	v4l2_ctrl_new_std(&ctx->ctrls, &coda_ctrl_ops,
 		V4L2_CID_MPEG_VIDEO_BITRATE, 0, 32767000, 1000, 0);
 	v4l2_ctrl_new_std(&ctx->ctrls, &coda_ctrl_ops,
-		V4L2_CID_MPEG_VIDEO_GOP_SIZE, 1, 60, 1, 16);
+		V4L2_CID_MPEG_VIDEO_GOP_SIZE, 0, max_gop_size, 1, 16);
 	v4l2_ctrl_new_std(&ctx->ctrls, &coda_ctrl_ops,
 		V4L2_CID_MPEG_VIDEO_H264_I_FRAME_QP, 0, 51, 1, 25);
 	v4l2_ctrl_new_std(&ctx->ctrls, &coda_ctrl_ops,