[PATCH v6 15/16] media: atomisp: allow raw Bayer capture

[Maurizio Casciano]

AtomISP currently rejects all raw formats and silently substitutes
YUV420. This prevents userspace camera processing stacks from obtaining
unprocessed sensor frames.

Enumerate only the raw format matching the sensor media-bus code and
reconcile raw requests with the code selected by the sensor. Userspace
opts in by selecting that raw V4L2 pixel format with VIDIOC_S_FMT.

Raw formats expose the full sensor transport frame so ISP2401 can use
its copy pipeline. Processed formats retain the existing global padding
behavior; selecting a smaller receiver crop remains a userspace pipeline
decision.

Signed-off-by: Maurizio Casciano <mauriziocasciano7@xxxxxxxxx>
Assisted-by: LLM sparse
---
 .../staging/media/atomisp/pci/atomisp_cmd.c   | 14 +++++++++++---
 .../staging/media/atomisp/pci/atomisp_ioctl.c | 19 ++++++++++++++++---
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/media/atomisp/pci/atomisp_cmd.c b/drivers/staging/media/atomisp/pci/atomisp_cmd.c
index 759effdb2e8d..99d2b73b160d 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_cmd.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_cmd.c
@@ -3815,8 +3815,7 @@ int atomisp_try_fmt(struct atomisp_device *isp, struct v4l2_pix_format *f,
 	int ret;
 
 	fmt = atomisp_get_format_bridge(f->pixelformat);
-	/* Currently, raw formats are broken!!! */
-	if (!fmt || fmt->sh_fmt == IA_CSS_FRAME_FORMAT_RAW) {
+	if (!fmt) {
 		f->pixelformat = V4L2_PIX_FMT_YUV420;
 
 		fmt = atomisp_get_format_bridge(f->pixelformat);
@@ -3838,7 +3837,10 @@ int atomisp_try_fmt(struct atomisp_device *isp, struct v4l2_pix_format *f,
 	 * resolution + padding. Add padding here and remove it again after
 	 * the set_fmt call, like atomisp_set_fmt_to_snr() does.
 	 */
-	atomisp_get_pix_padding(isp, f, &padding);
+	if (fmt->sh_fmt == IA_CSS_FRAME_FORMAT_RAW)
+		padding = (struct v4l2_area) { };
+	else
+		atomisp_get_pix_padding(isp, f, &padding);
 	v4l2_fill_mbus_format(&ffmt, f, fmt->mbus_code);
 	ffmt.width += padding.width;
 	ffmt.height += padding.height;
@@ -3858,6 +3860,12 @@ int atomisp_try_fmt(struct atomisp_device *isp, struct v4l2_pix_format *f,
 		return -EINVAL;
 	}
 
+	if (fmt->sh_fmt == IA_CSS_FRAME_FORMAT_RAW &&
+	    fmt->mbus_code != snr_fmt->mbus_code) {
+		fmt = snr_fmt;
+		f->pixelformat = fmt->pixelformat;
+	}
+
 	f->width = ffmt.width - padding.width;
 	f->height = ffmt.height - padding.height;
 
diff --git a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
index 87c29a940f9b..aa6d13a4de89 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
@@ -537,12 +537,21 @@ static int atomisp_enum_framesizes(struct file *file, void *priv,
 		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
 		.code = input->code,
 	};
+	const struct atomisp_format_bridge *format;
 	struct v4l2_subdev_state *act_sd_state;
+	struct v4l2_area padding = {
+		.width = pad_w,
+		.height = pad_h,
+	};
 	int ret;
 
 	if (!input->sensor)
 		return -EINVAL;
 
+	format = atomisp_get_format_bridge(fsize->pixel_format);
+	if (!format)
+		return -EINVAL;
+
 	if (input->crop_support)
 		return atomisp_enum_framesizes_crop(isp, fsize);
 
@@ -554,9 +563,12 @@ static int atomisp_enum_framesizes(struct file *file, void *priv,
 	if (ret)
 		return ret;
 
+	if (format->sh_fmt == IA_CSS_FRAME_FORMAT_RAW)
+		padding = (struct v4l2_area) { };
+
 	fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
-	fsize->discrete.width = fse.max_width - pad_w;
-	fsize->discrete.height = fse.max_height - pad_h;
+	fsize->discrete.width = fse.max_width - padding.width;
+	fsize->discrete.height = fse.max_height - padding.height;
 
 	return 0;
 }
@@ -630,7 +642,8 @@ static int atomisp_enum_fmt_cap(struct file *file, void *fh,
 		 *
 		 * FIXME: fix the pipeline to allow sensor format too.
 		 */
-		if (format->sh_fmt == IA_CSS_FRAME_FORMAT_RAW)
+		if (format->sh_fmt == IA_CSS_FRAME_FORMAT_RAW &&
+		    format->mbus_code != code.code)
 			continue;
 
 		/* Found a match. Now let's pick f->index'th one. */
-- 
2.53.0