[PATCH v2 25/25] media: atmel: atmel-isc: change format propagation to subdev into only verification

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

As a top MC video driver, the atmel-isc should not propagate the format to the
subdevice.
It should rather check at streamon() time if the subdev is properly configured
with a compatible format.
Removed the whole format finding logic, and reworked the format verification
at streamon time, such that the ISC will return an error if the subdevice
is not properly configured.
With this being done, the module parameter 'sensor_prefered' makes no sense
anymore. The ISC should not decide which format the sensor is using. The
ISC should only cope with the situation and inform userspace if the streaming
is possible in the current configuration.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
---
 drivers/media/platform/atmel/atmel-isc-base.c | 269 ++++++++----------
 drivers/media/platform/atmel/atmel-isc.h      |   1 +
 2 files changed, 123 insertions(+), 147 deletions(-)

diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c
index 31c8e3029eee..5f98b72b97c3 100644
--- a/drivers/media/platform/atmel/atmel-isc-base.c
+++ b/drivers/media/platform/atmel/atmel-isc-base.c
@@ -36,11 +36,6 @@ static unsigned int debug;
 module_param(debug, int, 0644);
 MODULE_PARM_DESC(debug, "debug level (0-2)");
 
-static unsigned int sensor_preferred = 1;
-module_param(sensor_preferred, uint, 0644);
-MODULE_PARM_DESC(sensor_preferred,
-		 "Sensor is preferred to output the specified format (1-on 0-off), default 1");
-
 #define ISC_IS_FORMAT_RAW(mbus_code) \
 	(((mbus_code) & 0xf000) == 0x3000)
 
@@ -532,7 +527,7 @@ static int isc_enum_fmt_vid_cap(struct file *file, void *priv,
 	 * 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 ||
+	if (isc->config.sd_format &&
 	    !ISC_IS_FORMAT_RAW(isc->config.sd_format->mbus_code))
 		return -EINVAL;
 
@@ -621,20 +616,30 @@ static int isc_try_validate_formats(struct isc_device *isc)
 		break;
 	default:
 	/* any other different formats are not supported */
+		v4l2_err(&isc->v4l2_dev, "Requested unsupported format.\n");
 		ret = -EINVAL;
 	}
 	v4l2_dbg(1, debug, &isc->v4l2_dev,
 		 "Format validation, requested rgb=%u, yuv=%u, grey=%u, bayer=%u\n",
 		 rgb, yuv, grey, bayer);
 
-	/* we cannot output RAW if we do not receive RAW */
-	if ((bayer) && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
+	if ((bayer) &&
+	    !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code)) {
+		v4l2_err(&isc->v4l2_dev, "Cannot output RAW if we do not receive RAW.\n");
 		return -EINVAL;
+	}
 
-	/* we cannot output GREY if we do not receive RAW/GREY */
 	if (grey && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code) &&
-	    !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code))
+	    !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
+		v4l2_err(&isc->v4l2_dev, "Cannot output GREY if we do not receive RAW/GREY.\n");
 		return -EINVAL;
+	}
+
+	if ((rgb || bayer || yuv) &&
+	    ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
+		v4l2_err(&isc->v4l2_dev, "Cannot convert GREY to another format.\n");
+		return -EINVAL;
+	}
 
 	return ret;
 }
@@ -862,7 +867,7 @@ static void isc_try_fse(struct isc_device *isc,
 	 * If we do not know yet which format the subdev is using, we cannot
 	 * do anything.
 	 */
-	if (!isc->try_config.sd_format)
+	if (!isc->config.sd_format)
 		return;
 
 	fse.code = isc->try_config.sd_format->mbus_code;
@@ -883,180 +888,137 @@ static void isc_try_fse(struct isc_device *isc,
 	}
 }
 
-static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f,
-			u32 *code)
+static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f)
 {
-	int i;
-	struct isc_format *sd_fmt = NULL, *direct_fmt = NULL;
 	struct v4l2_pix_format *pixfmt = &f->fmt.pix;
-	struct v4l2_subdev_pad_config pad_cfg = {};
-	struct v4l2_subdev_state pad_state = {
-		.pads = &pad_cfg
-		};
-	struct v4l2_subdev_format format = {
-		.which = V4L2_SUBDEV_FORMAT_TRY,
-	};
-	u32 mbus_code;
-	int ret;
-	bool rlp_dma_direct_dump = false;
+	unsigned int i;
 
 	if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 		return -EINVAL;
 
-	/* Step 1: find a RAW format that is supported */
-	for (i = 0; i < isc->num_user_formats; i++) {
-		if (ISC_IS_FORMAT_RAW(isc->user_formats[i]->mbus_code)) {
-			sd_fmt = isc->user_formats[i];
+	isc->try_config.fourcc = isc->user_formats[0]->fourcc;
+
+	/* find if the format requested is supported */
+	for (i = 0; i < isc->controller_formats_size; i++)
+		if (isc->controller_formats[i].fourcc == pixfmt->pixelformat) {
+			isc->try_config.fourcc = pixfmt->pixelformat;
 			break;
 		}
-	}
-	/* Step 2: We can continue with this RAW format, or we can look
-	 * for better: maybe sensor supports directly what we need.
-	 */
-	direct_fmt = find_format_by_fourcc(isc, pixfmt->pixelformat);
-
-	/* Step 3: We have both. We decide given the module parameter which
-	 * one to use.
-	 */
-	if (direct_fmt && sd_fmt && sensor_preferred)
-		sd_fmt = direct_fmt;
-
-	/* Step 4: we do not have RAW but we have a direct format. Use it. */
-	if (direct_fmt && !sd_fmt)
-		sd_fmt = direct_fmt;
-
-	/* Step 5: if we are using a direct format, we need to package
-	 * everything as 8 bit data and just dump it
-	 */
-	if (sd_fmt == direct_fmt)
-		rlp_dma_direct_dump = true;
-
-	/* Step 6: We have no format. This can happen if the userspace
-	 * requests some weird/invalid format.
-	 * In this case, default to whatever we have
-	 */
-	if (!sd_fmt && !direct_fmt) {
-		sd_fmt = isc->user_formats[isc->num_user_formats - 1];
-		v4l2_dbg(1, debug, &isc->v4l2_dev,
-			 "Sensor not supporting %.4s, using %.4s\n",
-			 (char *)&pixfmt->pixelformat, (char *)&sd_fmt->fourcc);
-	}
-
-	if (!sd_fmt) {
-		ret = -EINVAL;
-		goto isc_try_fmt_err;
-	}
-
-	/* Step 7: Print out what we decided for debugging */
-	v4l2_dbg(1, debug, &isc->v4l2_dev,
-		 "Preferring to have sensor using format %.4s\n",
-		 (char *)&sd_fmt->fourcc);
-
-	/* Step 8: at this moment we decided which format the subdev will use */
-	isc->try_config.sd_format = sd_fmt;
-
-	/* Limit to Atmel ISC hardware capabilities */
-	if (pixfmt->width > isc->max_width)
-		pixfmt->width = isc->max_width;
-	if (pixfmt->height > isc->max_height)
-		pixfmt->height = isc->max_height;
-
-	/*
-	 * The mbus format is the one the subdev outputs.
-	 * The pixels will be transferred in this format Sensor -> ISC
-	 */
-	mbus_code = sd_fmt->mbus_code;
-
-	/*
-	 * Validate formats. If the required format is not OK, default to raw.
-	 */
-
-	isc->try_config.fourcc = pixfmt->pixelformat;
-
-	if (isc_try_validate_formats(isc)) {
-		pixfmt->pixelformat = isc->try_config.fourcc = sd_fmt->fourcc;
-		/* Re-try to validate the new format */
-		ret = isc_try_validate_formats(isc);
-		if (ret)
-			goto isc_try_fmt_err;
-	}
-
-	ret = isc_try_configure_rlp_dma(isc, rlp_dma_direct_dump);
-	if (ret)
-		goto isc_try_fmt_err;
-
-	ret = isc_try_configure_pipeline(isc);
-	if (ret)
-		goto isc_try_fmt_err;
 
-	/* Obtain frame sizes if possible to have crop requirements ready */
-	isc_try_fse(isc, &pad_state);
-
-	v4l2_fill_mbus_format(&format.format, pixfmt, mbus_code);
-	ret = v4l2_subdev_call(isc->current_subdev->sd, pad, set_fmt,
-			       &pad_state, &format);
-	if (ret < 0)
-		goto isc_try_fmt_subdev_err;
+	/* If we did not find the requested format, we will fallback here */
+	pixfmt->pixelformat = isc->try_config.fourcc;
+	pixfmt->colorspace = V4L2_COLORSPACE_SRGB;
+	pixfmt->field = V4L2_FIELD_NONE;
 
-	v4l2_fill_pix_format(pixfmt, &format.format);
+	isc_try_configure_rlp_dma(isc, false);
 
 	/* Limit to Atmel ISC hardware capabilities */
-	if (pixfmt->width > isc->max_width)
-		pixfmt->width = isc->max_width;
-	if (pixfmt->height > isc->max_height)
-		pixfmt->height = isc->max_height;
+	v4l_bound_align_image(&pixfmt->width, 16, isc->max_width, 0,
+			      &pixfmt->height, 16, isc->max_height, 0, 0);
 
 	pixfmt->field = V4L2_FIELD_NONE;
 	pixfmt->bytesperline = (pixfmt->width * isc->try_config.bpp_v4l2) >> 3;
 	pixfmt->sizeimage = ((pixfmt->width * isc->try_config.bpp) >> 3) *
 			     pixfmt->height;
 
-	if (code)
-		*code = mbus_code;
+	isc->try_fmt = *f;
 
 	return 0;
+}
 
-isc_try_fmt_err:
-	v4l2_err(&isc->v4l2_dev, "Could not find any possible format for a working pipeline\n");
-isc_try_fmt_subdev_err:
-	memset(&isc->try_config, 0, sizeof(isc->try_config));
+static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
+{
+	isc_try_fmt(isc, f);
 
-	return ret;
+	/* make the try configuration active */
+	isc->config = isc->try_config;
+	isc->fmt = isc->try_fmt;
+
+	v4l2_dbg(1, debug, &isc->v4l2_dev, "ISC set_fmt to %.4s @%dx%d\n",
+		 (char *)&f->fmt.pix.pixelformat,
+		 f->fmt.pix.width, f->fmt.pix.height);
+
+	return 0;
 }
 
-static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
+static int isc_validate(struct isc_device *isc)
 {
+	int ret;
+	int i;
+	struct isc_format *sd_fmt = NULL;
+	struct v4l2_pix_format *pixfmt = &isc->fmt.fmt.pix;
 	struct v4l2_subdev_format format = {
 		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
+		.pad = isc->remote_pad,
+	};
+	struct v4l2_subdev_pad_config pad_cfg = {};
+	struct v4l2_subdev_state pad_state = {
+		.pads = &pad_cfg,
 	};
-	u32 mbus_code = 0;
-	int ret;
 
-	ret = isc_try_fmt(isc, f, &mbus_code);
+	/* Get current format from subdev */
+	ret = v4l2_subdev_call(isc->current_subdev->sd, pad, get_fmt, NULL,
+			       &format);
 	if (ret)
 		return ret;
 
-	v4l2_fill_mbus_format(&format.format, &f->fmt.pix, mbus_code);
-	ret = v4l2_subdev_call(isc->current_subdev->sd, pad,
-			       set_fmt, NULL, &format);
-	if (ret < 0)
-		return ret;
+	/* Identify the subdev's format configuration */
+	for (i = 0; i < isc->num_user_formats; i++)
+		if (isc->user_formats[i]->mbus_code == format.format.code) {
+			sd_fmt = isc->user_formats[i];
+			break;
+		}
 
-	/* Limit to Atmel ISC hardware capabilities */
-	if (f->fmt.pix.width > isc->max_width)
-		f->fmt.pix.width = isc->max_width;
-	if (f->fmt.pix.height > isc->max_height)
-		f->fmt.pix.height = isc->max_height;
+	/* Check if the format is not supported */
+	if (!sd_fmt) {
+		v4l2_err(&isc->v4l2_dev,
+			 "Current subdevice is streaming a media bus code that is not supported 0x%x\n",
+			 format.format.code);
+		return -EPIPE;
+	}
+
+	/* At this moment we know which format the subdev will use */
+	isc->try_config.sd_format = sd_fmt;
 
-	isc->fmt = *f;
+	/* If the sensor is not RAW, we can only do a direct dump */
+	if (!ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
+		isc_try_configure_rlp_dma(isc, true);
 
+	/* Check if the frame size is the same. Otherwise we may overflow */
+	if (pixfmt->height != format.format.height ||
+	    pixfmt->width != format.format.width) {
+		v4l2_err(&isc->v4l2_dev,
+			 "ISC not configured with the proper frame size: %dx%d\n",
+			 format.format.width, format.format.height);
+		return -EPIPE;
+	}
+
+	v4l2_dbg(1, debug, &isc->v4l2_dev,
+		 "Identified subdev using format %.4s with %dx%d %d bpp\n",
+		 (char *)&sd_fmt->fourcc, pixfmt->width, pixfmt->height,
+		 isc->try_config.bpp);
+
+	/* Reset and restart AWB if the subdevice changed the format */
 	if (isc->try_config.sd_format && isc->config.sd_format &&
 	    isc->try_config.sd_format != isc->config.sd_format) {
 		isc->ctrls.hist_stat = HIST_INIT;
 		isc_reset_awb_ctrls(isc);
 		isc_update_v4l2_ctrls(isc);
 	}
-	/* make the try configuration active */
+
+	/* Validate formats */
+	ret = isc_try_validate_formats(isc);
+	if (ret)
+		return ret;
+
+	/* Obtain frame sizes if possible to have crop requirements ready */
+	isc_try_fse(isc, &pad_state);
+
+	/* Configure ISC pipeline for the config */
+	ret = isc_try_configure_pipeline(isc);
+	if (ret)
+		return ret;
+
 	isc->config = isc->try_config;
 
 	v4l2_dbg(1, debug, &isc->v4l2_dev, "New ISC configuration in place\n");
@@ -1064,6 +1026,19 @@ static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
 	return 0;
 }
 
+static int isc_streamon(struct file *file, void *priv, enum v4l2_buf_type bt)
+{
+	struct isc_device *isc = video_drvdata(file);
+	int ret;
+
+	ret = isc_validate(isc);
+
+	if (ret)
+		return ret;
+
+	return vb2_ioctl_streamon(file, priv, bt);
+}
+
 static int isc_s_fmt_vid_cap(struct file *file, void *priv,
 			      struct v4l2_format *f)
 {
@@ -1080,7 +1055,7 @@ static int isc_try_fmt_vid_cap(struct file *file, void *priv,
 {
 	struct isc_device *isc = video_drvdata(file);
 
-	return isc_try_fmt(isc, f, NULL);
+	return isc_try_fmt(isc, f);
 }
 
 static int isc_enum_input(struct file *file, void *priv,
@@ -1176,7 +1151,7 @@ static const struct v4l2_ioctl_ops isc_ioctl_ops = {
 	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
 	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
 	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
-	.vidioc_streamon		= vb2_ioctl_streamon,
+	.vidioc_streamon		= isc_streamon,
 	.vidioc_streamoff		= vb2_ioctl_streamoff,
 
 	.vidioc_g_parm			= isc_g_parm,
@@ -1879,7 +1854,7 @@ static int isc_set_default_fmt(struct isc_device *isc)
 	};
 	int ret;
 
-	ret = isc_try_fmt(isc, &f, NULL);
+	ret = isc_try_fmt(isc, &f);
 	if (ret)
 		return ret;
 
diff --git a/drivers/media/platform/atmel/atmel-isc.h b/drivers/media/platform/atmel/atmel-isc.h
index c2cb805faff3..7081698adddd 100644
--- a/drivers/media/platform/atmel/atmel-isc.h
+++ b/drivers/media/platform/atmel/atmel-isc.h
@@ -297,6 +297,7 @@ struct isc_device {
 	struct completion	comp;
 
 	struct v4l2_format	fmt;
+	struct v4l2_format	try_fmt;
 	struct isc_format	**user_formats;
 	unsigned int		num_user_formats;
 
-- 
2.25.1