media: imx: add 8-bit grayscale support

The IPUv3 code has 8-bit grayscale capture support.
Enable imx-media to use it.
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/staging/media/imx/imx-media-csi.c

@@ -400,6 +400,7 @@ static int csi_idmac_setup_channel(struct csi_priv *priv)
 	case V4L2_PIX_FMT_SGBRG8:
 	case V4L2_PIX_FMT_SGRBG8:
 	case V4L2_PIX_FMT_SRGGB8:
+	case V4L2_PIX_FMT_GREY:
 		burst_size = 16;
 		passthrough = true;
 		passthrough_bits = 8;

drivers/staging/media/imx/imx-media-utils.c

@@ -93,7 +93,7 @@ static const struct imx_media_pixfmt rgb_formats[] = {
 		.bpp    = 32,
 		.ipufmt = true,
 	},
-	/*** raw bayer formats start here ***/
+	/*** raw bayer and grayscale formats start here ***/
 	{
 		.fourcc = V4L2_PIX_FMT_SBGGR8,
 		.codes  = {MEDIA_BUS_FMT_SBGGR8_1X8},
@@ -162,6 +162,12 @@ static const struct imx_media_pixfmt rgb_formats[] = {
 		.cs     = IPUV3_COLORSPACE_RGB,
 		.bpp    = 16,
 		.bayer  = true,
+	}, {
+		.fourcc = V4L2_PIX_FMT_GREY,
+		.codes = {MEDIA_BUS_FMT_Y8_1X8},
+		.cs     = IPUV3_COLORSPACE_RGB,
+		.bpp    = 8,
+		.bayer  = true,
 	},
 	/***
 	 * non-mbus RGB formats start here. NOTE! when adding non-mbus