[PATCH v4 14/15] 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.

Link: https://lore.kernel.org/linux-media/apCc_pt5dDxGJrei@ashevche-desk.local/
Link: https://lore.kernel.org/linux-media/apF0Cds9fnqQ7XRg@kekkonen.localdomain/
Signed-off-by: Maurizio Casciano <mauriziocasciano7@xxxxxxxxx>
Assisted-by: Codex:gpt-5.6-sol sparse
---
 .../staging/media/atomisp/pci/atomisp_cmd.c   | 19 +++++++++++++------
 .../staging/media/atomisp/pci/atomisp_ioctl.c | 19 ++++++++++++++++---
 2 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/media/atomisp/pci/atomisp_cmd.c b/drivers/staging/media/atomisp/pci/atomisp_cmd.c
index 51dd59d98b3b..3d62cb948e31 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_cmd.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_cmd.c
@@ -3572,7 +3572,6 @@ void atomisp_get_padding(struct atomisp_device *isp, struct v4l2_area size,
 	u32 min_pad_w = ISP2400_MIN_PAD_W;
 	u32 min_pad_h = ISP2400_MIN_PAD_H;
 	struct v4l2_mbus_framefmt *sink;
-
 	if (!input->crop_support) {
 		pad->width = pad_w;
 		pad->height = pad_h;
@@ -3806,8 +3805,7 @@ 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);
@@ -3829,9 +3827,13 @@ 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.
 	 */
-	size.width = f->width;
-	size.height = f->height;
-	atomisp_get_padding(isp, size, &padding);
+	if (fmt->sh_fmt == IA_CSS_FRAME_FORMAT_RAW) {
+		padding = (struct v4l2_area) { };
+	} else {
+		size.width = f->width;
+		size.height = f->height;
+		atomisp_get_padding(isp, size, &padding);
+	}
 	v4l2_fill_mbus_format(&ffmt, f, fmt->mbus_code);
 	ffmt.width += padding.width;
 	ffmt.height += padding.height;
@@ -3850,6 +3852,11 @@ int atomisp_try_fmt(struct atomisp_device *isp, struct v4l2_pix_format *f,
 			ffmt.code);
 		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 43bca68d1e6d..edad38809fc9 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
@@ -540,12 +540,21 @@ 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);
 
@@ -557,9 +566,12 @@ 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;
 }
@@ -633,7 +645,8 @@ 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