[libcamera-devel] [PATCH 1/2] include: linux: Add an AWB layout structure

[Jean-Michel Hautbois]

This patch was proposed in:
https://lore.kernel.org/linux-media/20210831185140.77400-1-jeanmichel.hautbois@ideasonboard.com/

It introduces the AWB metadata layout as a structure in the kernel
header, to make it clear for userspace applications.

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
---
 include/linux/intel-ipu3.h | 36 ++++++++++++++++++++++++++++--------
 1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/include/linux/intel-ipu3.h b/include/linux/intel-ipu3.h
index ee0e6d0e..cb37d448 100644
--- a/include/linux/intel-ipu3.h
+++ b/include/linux/intel-ipu3.h
@@ -59,20 +59,40 @@ struct ipu3_uapi_grid_config {
 	__u16 y_end;
 } __attribute__((packed));
 
+/**
+ * struct ipu3_uapi_awb_set_item - Memory layout for each cell in AWB
+ *
+ * @Gr_avg:	Green average for red lines in the cell.
+ * @R_avg:	Red average in the cell.
+ * @B_avg:	Blue average in the cell.
+ * @Gb_avg:	Green average for blue lines in the cell.
+ * @sat_ratio:  Saturation ratio in the cell.
+ * @padding0:   Unused byte for padding.
+ * @padding1:   Unused byte for padding.
+ * @padding2:   Unused byte for padding.
+ */
+struct ipu3_uapi_awb_set_item {
+	unsigned char Gr_avg;
+	unsigned char R_avg;
+	unsigned char B_avg;
+	unsigned char Gb_avg;
+	unsigned char sat_ratio;
+	unsigned char padding0;
+	unsigned char padding1;
+	unsigned char padding2;
+} __attribute__((packed));
+
 /*
  * The grid based data is divided into "slices" called set, each slice of setX
  * refers to ipu3_uapi_grid_config width * height_per_slice.
  */
 #define IPU3_UAPI_AWB_MAX_SETS				60
-/* Based on grid size 80 * 60 and cell size 16 x 16 */
-#define IPU3_UAPI_AWB_SET_SIZE				1280
-#define IPU3_UAPI_AWB_MD_ITEM_SIZE			8
-#define IPU3_UAPI_AWB_SPARE_FOR_BUBBLES \
-	(IPU3_UAPI_MAX_BUBBLE_SIZE * IPU3_UAPI_MAX_STRIPES * \
-	 IPU3_UAPI_AWB_MD_ITEM_SIZE)
+#define AWB_PUBLIC_NUM_OF_ITEMS_IN_SET			160
+/* Based on max grid height + Spare for bubbles */
+#define AWB_PUBLIC_NUM_OF_SETS_IN_BUFFER IPU3_UAPI_AWB_MAX_SETS + \
+	(IPU3_UAPI_MAX_BUBBLE_SIZE * IPU3_UAPI_MAX_STRIPES)
 #define IPU3_UAPI_AWB_MAX_BUFFER_SIZE \
-	(IPU3_UAPI_AWB_MAX_SETS * \
-	 (IPU3_UAPI_AWB_SET_SIZE + IPU3_UAPI_AWB_SPARE_FOR_BUBBLES))
+        AWB_PUBLIC_NUM_OF_SETS_IN_BUFFER * AWB_PUBLIC_NUM_OF_ITEMS_IN_SET
 
 
 /**
-- 
2.30.2