openwrt/target/linux/brcm2708/patches-4.19/950-0730-media-bcm2835-unicam-Support-unpacking-CSI-format-to.patch

From 5ae0488f5fc682877ae2a5d454f70884e62120ef Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.org>
Date: Thu, 3 Oct 2019 13:35:01 +0100
Subject: [PATCH] media: bcm2835-unicam: Support unpacking CSI format
 to 16bpp

The CSI packed formats are not the easiest to work with, and
the peripheral supports unpacking them to 16bpp (but NOT
shifting the data up into the MSBs).
Where V4L2 exposes a pixfmt for both packed and unpacked
formats advertise both as being supported, and unpack the
data in the peripheral.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
---
 .../media/platform/bcm2835/bcm2835-unicam.c   | 102 +++++++++---------
 1 file changed, 51 insertions(+), 51 deletions(-)

--- a/drivers/media/platform/bcm2835/bcm2835-unicam.c
+++ b/drivers/media/platform/bcm2835/bcm2835-unicam.c
@@ -15,12 +15,15 @@
  *
  * This driver directly controls the Unicam peripheral - there is no
  * involvement with the VideoCore firmware. Unicam receives CSI-2 or
- * CCP2 data and writes it into SDRAM. The only potential processing options are
- * to repack Bayer data into an alternate format, and applying windowing.
- * The repacking does not shift the data, so could repack V4L2_PIX_FMT_Sxxxx10P
+ * CCP2 data and writes it into SDRAM.
+ * The only potential processing options are to repack Bayer data into an
+ * alternate format, and applying windowing.
+ * The repacking does not shift the data, so can repack V4L2_PIX_FMT_Sxxxx10P
  * to V4L2_PIX_FMT_Sxxxx10, or V4L2_PIX_FMT_Sxxxx12P to V4L2_PIX_FMT_Sxxxx12,
- * but not generically up to V4L2_PIX_FMT_Sxxxx16.
- * Adding support for repacking and windowing may be added later.
+ * but not generically up to V4L2_PIX_FMT_Sxxxx16. The driver will add both
+ * formats where the relevant formats are defined, and will automatically
+ * configure the repacking as required.
+ * Support for windowing may be added later.
  *
  * It should be possible to connect this driver to any sensor with a
  * suitable output interface and V4L2 subdevice driver.
@@ -122,13 +125,16 @@ MODULE_PARM_DESC(debug, "Debug level 0-3
 
 /*
  * struct unicam_fmt - Unicam media bus format information
- * @pixelformat: V4L2 pixel format FCC identifier.
+ * @pixelformat: V4L2 pixel format FCC identifier. 0 if n/a.
+ * @repacked_fourcc: V4L2 pixel format FCC identifier if the data is expanded
+ * out to 16bpp. 0 if n/a.
  * @code: V4L2 media bus format code.
- * @depth: Bits per pixel (when stored in memory).
+ * @depth: Bits per pixel as delivered from the source.
  * @csi_dt: CSI data type.
  */
 struct unicam_fmt {
 	u32	fourcc;
+	u32	repacked_fourcc;
 	u32	code;
 	u8	depth;
 	u8	csi_dt;
@@ -235,41 +241,49 @@ static const struct unicam_fmt formats[]
 		.csi_dt		= 0x2a,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SBGGR10P,
+		.repacked_fourcc = V4L2_PIX_FMT_SBGGR10,
 		.code		= MEDIA_BUS_FMT_SBGGR10_1X10,
 		.depth		= 10,
 		.csi_dt		= 0x2b,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGBRG10P,
+		.repacked_fourcc = V4L2_PIX_FMT_SGBRG10,
 		.code		= MEDIA_BUS_FMT_SGBRG10_1X10,
 		.depth		= 10,
 		.csi_dt		= 0x2b,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGRBG10P,
+		.repacked_fourcc = V4L2_PIX_FMT_SGRBG10,
 		.code		= MEDIA_BUS_FMT_SGRBG10_1X10,
 		.depth		= 10,
 		.csi_dt		= 0x2b,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SRGGB10P,
+		.repacked_fourcc = V4L2_PIX_FMT_SRGGB10,
 		.code		= MEDIA_BUS_FMT_SRGGB10_1X10,
 		.depth		= 10,
 		.csi_dt		= 0x2b,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SBGGR12P,
+		.repacked_fourcc = V4L2_PIX_FMT_SBGGR12,
 		.code		= MEDIA_BUS_FMT_SBGGR12_1X12,
 		.depth		= 12,
 		.csi_dt		= 0x2c,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGBRG12P,
+		.repacked_fourcc = V4L2_PIX_FMT_SGBRG12,
 		.code		= MEDIA_BUS_FMT_SGBRG12_1X12,
 		.depth		= 12,
 		.csi_dt		= 0x2c,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SGRBG12P,
+		.repacked_fourcc = V4L2_PIX_FMT_SGRBG12,
 		.code		= MEDIA_BUS_FMT_SGRBG12_1X12,
 		.depth		= 12,
 		.csi_dt		= 0x2c,
 	}, {
 		.fourcc		= V4L2_PIX_FMT_SRGGB12P,
+		.repacked_fourcc = V4L2_PIX_FMT_SRGGB12,
 		.code		= MEDIA_BUS_FMT_SRGGB12_1X12,
 		.depth		= 12,
 		.csi_dt		= 0x2c,
@@ -439,20 +453,6 @@ static inline void unicam_runtime_put(st
 }
 
 /* Format setup functions */
-static int find_mbus_depth_by_code(u32 code)
-{
-	const struct unicam_fmt *fmt;
-	unsigned int k;
-
-	for (k = 0; k < ARRAY_SIZE(formats); k++) {
-		fmt = &formats[k];
-		if (fmt->code == code)
-			return fmt->depth;
-	}
-
-	return 0;
-}
-
 static const struct unicam_fmt *find_format_by_code(u32 code)
 {
 	unsigned int k;
@@ -470,7 +470,8 @@ static const struct unicam_fmt *find_for
 	unsigned int k;
 
 	for (k = 0; k < ARRAY_SIZE(formats); k++) {
-		if (formats[k].fourcc == pixelformat)
+		if (formats[k].fourcc == pixelformat ||
+		    formats[k].repacked_fourcc == pixelformat)
 			return &formats[k];
 	}
 
@@ -478,9 +479,14 @@ static const struct unicam_fmt *find_for
 }
 
 static inline unsigned int bytes_per_line(u32 width,
-					  const struct unicam_fmt *fmt)
+					  const struct unicam_fmt *fmt,
+					  u32 v4l2_fourcc)
 {
-	return ALIGN((width * fmt->depth) >> 3, BPL_ALIGNMENT);
+	if (v4l2_fourcc == fmt->repacked_fourcc)
+		/* Repacking always goes to 16bpp */
+		return ALIGN(width << 1, BPL_ALIGNMENT);
+	else
+		return ALIGN((width * fmt->depth) >> 3, BPL_ALIGNMENT);
 }
 
 static int __subdev_get_format(struct unicam_device *dev,
@@ -538,7 +544,8 @@ static int unicam_calc_format_size_bpl(s
 			      &f->fmt.pix.height, MIN_HEIGHT, MAX_HEIGHT, 0,
 			      0);
 
-	min_bytesperline = bytes_per_line(f->fmt.pix.width, fmt);
+	min_bytesperline = bytes_per_line(f->fmt.pix.width, fmt,
+					  f->fmt.pix.pixelformat);
 
 	if (f->fmt.pix.bytesperline > min_bytesperline &&
 	    f->fmt.pix.bytesperline <= MAX_BYTESPERLINE)
@@ -738,6 +745,13 @@ static int unicam_enum_fmt_vid_cap(struc
 				}
 				index++;
 			}
+			if (fmt->repacked_fourcc) {
+				if (index == f->index) {
+					f->pixelformat = fmt->repacked_fourcc;
+					break;
+				}
+				index++;
+			}
 		}
 	}
 
@@ -858,7 +872,10 @@ static int unicam_try_fmt_vid_cap(struct
 			}
 		}
 
-		f->fmt.pix.pixelformat = fmt->fourcc;
+		if (fmt->fourcc)
+			f->fmt.pix.pixelformat = fmt->fourcc;
+		else
+			f->fmt.pix.pixelformat = fmt->repacked_fourcc;
 	}
 
 	return unicam_calc_format_size_bpl(dev, fmt, f);
@@ -998,16 +1015,14 @@ static void unicam_wr_dma_config(struct
 
 static void unicam_set_packing_config(struct unicam_device *dev)
 {
-	int mbus_depth = find_mbus_depth_by_code(dev->fmt->code);
-	int v4l2_depth = dev->fmt->depth;
 	int pack, unpack;
 	u32 val;
 
-	if (mbus_depth == v4l2_depth) {
+	if (dev->v_fmt.fmt.pix.pixelformat == dev->fmt->fourcc) {
 		unpack = UNICAM_PUM_NONE;
 		pack = UNICAM_PPM_NONE;
 	} else {
-		switch (mbus_depth) {
+		switch (dev->fmt->depth) {
 		case 8:
 			unpack = UNICAM_PUM_UNPACK8;
 			break;
@@ -1028,26 +1043,8 @@ static void unicam_set_packing_config(st
 			break;
 		}
 
-		switch (v4l2_depth) {
-		case 8:
-			pack = UNICAM_PPM_PACK8;
-			break;
-		case 10:
-			pack = UNICAM_PPM_PACK10;
-			break;
-		case 12:
-			pack = UNICAM_PPM_PACK12;
-			break;
-		case 14:
-			pack = UNICAM_PPM_PACK14;
-			break;
-		case 16:
-			pack = UNICAM_PPM_PACK16;
-			break;
-		default:
-			pack = UNICAM_PPM_NONE;
-			break;
-		}
+		/* Repacking is always to 16bpp */
+		pack = UNICAM_PPM_PACK16;
 	}
 
 	val = 0;
@@ -1893,7 +1890,10 @@ static int unicam_probe_complete(struct
 	}
 
 	unicam->fmt = fmt;
-	unicam->v_fmt.fmt.pix.pixelformat = fmt->fourcc;
+	if (fmt->fourcc)
+		unicam->v_fmt.fmt.pix.pixelformat = fmt->fourcc;
+	else
+		unicam->v_fmt.fmt.pix.pixelformat = fmt->repacked_fourcc;
 
 	/* Read current subdev format */
 	unicam_reset_format(unicam);