media: microchip: microchip-isc: prepare for media controller support

Prepare the support for media-controller.
This means that the capabilities of the driver have changed and now it's
capable of media controller operations.
The driver will register its media device, and add the video entity to this
media device. The subdevices are registered to the same media device.
The ISC will have a base entity which is auto-detected as
microchip_isc_base.
It will also register a subdevice that allows cropping of the incoming
frame to the maximum frame size supported by the ISC.
The ISC will create a link between the subdevice that is asynchronously
registered and the microchip_isc_scaler entity.
Then, the microchip_isc_scaler and microchip_isc_base are connected
through another link.
This patch does not change the previous capability of the driver, the
fact that the format is still being propagated from the top video node
down to the sensor.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

1 files changed, 262 insertions, 0 deletions

diff --git a/drivers/media/platform/microchip/microchip-isc-scaler.c b/drivers/media/platform/microchip/microchip-isc-scaler.c
new file mode 100644
index 000000000000..80fff803e6bb
--- /dev/null
+++ b/drivers/media/platform/microchip/microchip-isc-scaler.c
@@ -0,0 +1,262 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Microchip Image Sensor Controller (ISC) Scaler entity support
+ *
+ * Copyright (C) 2022 Microchip Technology, Inc.
+ *
+ * Author: Eugen Hristev <eugen.hristev@microchip.com>
+ *
+ */
+
+#include <media/media-device.h>
+#include <media/media-entity.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+
+#include "microchip-isc-regs.h"
+#include "microchip-isc.h"
+
+static void isc_scaler_prepare_fmt(struct v4l2_mbus_framefmt *framefmt)
+{
+	framefmt->colorspace = V4L2_COLORSPACE_SRGB;
+	framefmt->field = V4L2_FIELD_NONE;
+	framefmt->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
+	framefmt->quantization = V4L2_QUANTIZATION_DEFAULT;
+	framefmt->xfer_func = V4L2_XFER_FUNC_DEFAULT;
+};
+
+static int isc_scaler_get_fmt(struct v4l2_subdev *sd,
+			      struct v4l2_subdev_state *sd_state,
+			      struct v4l2_subdev_format *format)
+{
+	struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);
+	struct v4l2_mbus_framefmt *v4l2_try_fmt;
+
+	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
+		v4l2_try_fmt = v4l2_subdev_get_try_format(sd, sd_state,
+							  format->pad);
+		format->format = *v4l2_try_fmt;
+
+		return 0;
+	}
+
+	format->format = isc->scaler_format[format->pad];
+
+	return 0;
+}
+
+static int isc_scaler_set_fmt(struct v4l2_subdev *sd,
+			      struct v4l2_subdev_state *sd_state,
+			      struct v4l2_subdev_format *req_fmt)
+{
+	struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);
+	struct v4l2_mbus_framefmt *v4l2_try_fmt;
+	struct isc_format *fmt;
+	unsigned int i;
+
+	/* Source format is fixed, we cannot change it */
+	if (req_fmt->pad == ISC_SCALER_PAD_SOURCE) {
+		req_fmt->format = isc->scaler_format[ISC_SCALER_PAD_SOURCE];
+		return 0;
+	}
+
+	/* There is no limit on the frame size on the sink pad */
+	v4l_bound_align_image(&req_fmt->format.width, 16, UINT_MAX, 0,
+			      &req_fmt->format.height, 16, UINT_MAX, 0, 0);
+
+	isc_scaler_prepare_fmt(&req_fmt->format);
+
+	fmt = isc_find_format_by_code(isc, req_fmt->format.code, &i);
+
+	if (!fmt)
+		fmt = &isc->formats_list[0];
+
+	req_fmt->format.code = fmt->mbus_code;
+
+	if (req_fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
+		v4l2_try_fmt = v4l2_subdev_get_try_format(sd, sd_state,
+							  req_fmt->pad);
+		*v4l2_try_fmt = req_fmt->format;
+		/* Trying on the sink pad makes the source pad change too */
+		v4l2_try_fmt = v4l2_subdev_get_try_format(sd, sd_state,
+							  ISC_SCALER_PAD_SOURCE);
+		*v4l2_try_fmt = req_fmt->format;
+
+		v4l_bound_align_image(&v4l2_try_fmt->width,
+				      16, isc->max_width, 0,
+				      &v4l2_try_fmt->height,
+				      16, isc->max_height, 0, 0);
+		/* if we are just trying, we are done */
+		return 0;
+	}
+
+	isc->scaler_format[ISC_SCALER_PAD_SINK] = req_fmt->format;
+
+	/* The source pad is the same as the sink, but we have to crop it */
+	isc->scaler_format[ISC_SCALER_PAD_SOURCE] =
+		isc->scaler_format[ISC_SCALER_PAD_SINK];
+	v4l_bound_align_image
+		(&isc->scaler_format[ISC_SCALER_PAD_SOURCE].width, 16,
+		 isc->max_width, 0,
+		 &isc->scaler_format[ISC_SCALER_PAD_SOURCE].height, 16,
+		 isc->max_height, 0, 0);
+
+	return 0;
+}
+
+static int isc_scaler_enum_mbus_code(struct v4l2_subdev *sd,
+				     struct v4l2_subdev_state *sd_state,
+				     struct v4l2_subdev_mbus_code_enum *code)
+{
+	struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);
+
+	/*
+	 * All formats supported by the ISC are supported by the scaler.
+	 * Advertise the formats which the ISC can take as input, as the scaler
+	 * entity cropping is part of the PFE module (parallel front end)
+	 */
+	if (code->index < isc->formats_list_size) {
+		code->code = isc->formats_list[code->index].mbus_code;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int isc_scaler_g_sel(struct v4l2_subdev *sd,
+			    struct v4l2_subdev_state *sd_state,
+			    struct v4l2_subdev_selection *sel)
+{
+	struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);
+
+	if (sel->pad == ISC_SCALER_PAD_SOURCE)
+		return -EINVAL;
+
+	if (sel->target != V4L2_SEL_TGT_CROP_BOUNDS &&
+	    sel->target != V4L2_SEL_TGT_CROP)
+		return -EINVAL;
+
+	sel->r.height = isc->scaler_format[ISC_SCALER_PAD_SOURCE].height;
+	sel->r.width = isc->scaler_format[ISC_SCALER_PAD_SOURCE].width;
+
+	sel->r.left = 0;
+	sel->r.top = 0;
+
+	return 0;
+}
+
+static int isc_scaler_init_cfg(struct v4l2_subdev *sd,
+			       struct v4l2_subdev_state *sd_state)
+{
+	struct v4l2_mbus_framefmt *v4l2_try_fmt =
+		v4l2_subdev_get_try_format(sd, sd_state, 0);
+	struct v4l2_rect *try_crop;
+	struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);
+
+	*v4l2_try_fmt = isc->scaler_format[ISC_SCALER_PAD_SOURCE];
+
+	try_crop = v4l2_subdev_get_try_crop(sd, sd_state, 0);
+
+	try_crop->top = 0;
+	try_crop->left = 0;
+	try_crop->width = v4l2_try_fmt->width;
+	try_crop->height = v4l2_try_fmt->height;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_pad_ops isc_scaler_pad_ops = {
+	.enum_mbus_code = isc_scaler_enum_mbus_code,
+	.set_fmt = isc_scaler_set_fmt,
+	.get_fmt = isc_scaler_get_fmt,
+	.get_selection = isc_scaler_g_sel,
+	.init_cfg = isc_scaler_init_cfg,
+};
+
+static const struct v4l2_subdev_ops xisc_scaler_subdev_ops = {
+	.pad = &isc_scaler_pad_ops,
+};
+
+int isc_scaler_init(struct isc_device *isc)
+{
+	int ret;
+
+	v4l2_subdev_init(&isc->scaler_sd, &xisc_scaler_subdev_ops);
+
+	isc->scaler_sd.owner = THIS_MODULE;
+	isc->scaler_sd.dev = isc->dev;
+	snprintf(isc->scaler_sd.name, sizeof(isc->scaler_sd.name),
+		 "microchip_isc_scaler");
+
+	isc->scaler_sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	isc->scaler_sd.entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
+	isc->scaler_pads[ISC_SCALER_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
+	isc->scaler_pads[ISC_SCALER_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
+
+	isc_scaler_prepare_fmt(&isc->scaler_format[ISC_SCALER_PAD_SOURCE]);
+	isc->scaler_format[ISC_SCALER_PAD_SOURCE].height = isc->max_height;
+	isc->scaler_format[ISC_SCALER_PAD_SOURCE].width = isc->max_width;
+	isc->scaler_format[ISC_SCALER_PAD_SOURCE].code =
+		 isc->formats_list[0].mbus_code;
+
+	isc->scaler_format[ISC_SCALER_PAD_SINK] =
+		 isc->scaler_format[ISC_SCALER_PAD_SOURCE];
+
+	ret = media_entity_pads_init(&isc->scaler_sd.entity,
+				     ISC_SCALER_PADS_NUM,
+				     isc->scaler_pads);
+	if (ret < 0) {
+		dev_err(isc->dev, "scaler sd media entity init failed\n");
+		return ret;
+	}
+
+	ret = v4l2_device_register_subdev(&isc->v4l2_dev, &isc->scaler_sd);
+	if (ret < 0) {
+		dev_err(isc->dev, "scaler sd failed to register subdev\n");
+		return ret;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(isc_scaler_init);
+
+int isc_scaler_link(struct isc_device *isc)
+{
+	int ret;
+
+	ret = media_create_pad_link(&isc->current_subdev->sd->entity,
+				    isc->remote_pad, &isc->scaler_sd.entity,
+				    ISC_SCALER_PAD_SINK,
+				    MEDIA_LNK_FL_ENABLED |
+				    MEDIA_LNK_FL_IMMUTABLE);
+
+	if (ret < 0) {
+		dev_err(isc->dev, "Failed to create pad link: %s to %s\n",
+			isc->current_subdev->sd->entity.name,
+			isc->scaler_sd.entity.name);
+		return ret;
+	}
+
+	dev_dbg(isc->dev, "link with %s pad: %d\n",
+		isc->current_subdev->sd->name, isc->remote_pad);
+
+	ret = media_create_pad_link(&isc->scaler_sd.entity,
+				    ISC_SCALER_PAD_SOURCE,
+				    &isc->video_dev.entity, ISC_PAD_SINK,
+				    MEDIA_LNK_FL_ENABLED |
+				    MEDIA_LNK_FL_IMMUTABLE);
+
+	if (ret < 0) {
+		dev_err(isc->dev, "Failed to create pad link: %s to %s\n",
+			isc->scaler_sd.entity.name,
+			isc->video_dev.entity.name);
+		return ret;
+	}
+
+	dev_dbg(isc->dev, "link with %s pad: %d\n", isc->scaler_sd.name,
+		ISC_SCALER_PAD_SOURCE);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(isc_scaler_link);
+