[PATCH v2 11/25] media: atmel: atmel-isc-base: implement mbus_code support in enumfmt

[Eugen Hristev <eugen.hristev@microchip.com>]

If enumfmt is called with an mbus_code, the enumfmt handler should only
return the formats that are supported for this mbus_code.
To make it more easy to understand the formats, changed the report order
to report first the native formats, and after that the formats that the ISC
can convert to.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
---
 drivers/media/platform/atmel/atmel-isc-base.c | 51 ++++++++++++++++---
 1 file changed, 43 insertions(+), 8 deletions(-)

diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c
index bf638d201b29..2cb8446ff90c 100644
--- a/drivers/media/platform/atmel/atmel-isc-base.c
+++ b/drivers/media/platform/atmel/atmel-isc-base.c
@@ -498,21 +498,56 @@ static int isc_enum_fmt_vid_cap(struct file *file, void *priv,
 	u32 index = f->index;
 	u32 i, supported_index;
 
-	if (index < isc->controller_formats_size) {
-		f->pixelformat = isc->controller_formats[index].fourcc;
-		return 0;
+	supported_index = 0;
+
+	for (i = 0; i < isc->formats_list_size; i++) {
+		if (!isc->formats_list[i].sd_support)
+			continue;
+		/*
+		 * If specific mbus_code is requested, provide only
+		 * supported formats with this mbus code
+		 */
+		if (f->mbus_code && f->mbus_code !=
+		    isc->formats_list[i].mbus_code)
+			continue;
+		if (supported_index == index) {
+			f->pixelformat = isc->formats_list[i].fourcc;
+			return 0;
+		}
+		supported_index++;
 	}
 
-	index -= isc->controller_formats_size;
+	/*
+	 * If the sensor does not support this mbus_code whatsoever,
+	 * there is no reason to advertise any of our output formats
+	 */
+	if (supported_index == 0)
+		return -EINVAL;
+
+	/*
+	 * If the sensor uses a format that is not raw, then we cannot
+	 * convert it to any of the formats that we usually can with a
+	 * RAW sensor. Thus, do not advertise them.
+	 */
+	if (!isc->config.sd_format ||
+	    !ISC_IS_FORMAT_RAW(isc->config.sd_format->mbus_code))
+		return -EINVAL;
 
+	/*
+	 * Iterate again through the formats that we can convert to.
+	 * However, to avoid duplicates, skip the formats that
+	 * the sensor already supports directly
+	 */
+	index -= supported_index;
 	supported_index = 0;
 
-	for (i = 0; i < isc->formats_list_size; i++) {
-		if (!ISC_IS_FORMAT_RAW(isc->formats_list[i].mbus_code) ||
-		    !isc->formats_list[i].sd_support)
+	for (i = 0; i < isc->controller_formats_size; i++) {
+		/* if this format is already supported by sensor, skip it */
+		if (find_format_by_fourcc(isc, isc->controller_formats[i].fourcc))
 			continue;
 		if (supported_index == index) {
-			f->pixelformat = isc->formats_list[i].fourcc;
+			f->pixelformat =
+				isc->controller_formats[i].fourcc;
 			return 0;
 		}
 		supported_index++;
-- 
2.25.1