media: staging: media: Add support for the Allwinner A31 ISP

Some Allwinner platforms come with an Image Signal Processor, which
supports various features in order to enhance and transform data
received by image sensors into good-looking pictures. In most cases,
the data is raw bayer, which gets internally converted to RGB and
finally YUV, which is what the hardware produces.

This driver supports ISPs that are similar to the A31 ISP, which was
the first standalone ISP found in Allwinner platforms. Simpler ISP
blocks were found in the A10 and A20, where they are tied to a CSI
controller. Newer generations of Allwinner SoCs (starting with the
H6, H616, etc) come with a new camera subsystem and revised ISP.
Even though these previous and next-generation ISPs are somewhat
similar to the A31 ISP, they have enough significant differences to
be out of the scope of this driver.

While the ISP supports many features, including 3A and many
enhancement blocks, this implementation is limited to the following:
- V3s (V3/S3) platform support;
- Bayer media bus formats as input;
- Semi-planar YUV (NV12/NV21) as output;
- Debayering with per-component gain and offset configuration;
- 2D noise filtering with configurable coefficients.

Since many features are missing from the associated uAPI, the driver
is aimed to integrate staging until all features are properly
described.

On the technical side, it uses the v4l2 and media controller APIs,
with a video node for capture, a processor subdev and a video node
for parameters submission. A specific uAPI structure and associated
v4l2 meta format are used to configure parameters of the supported
modules.

One particular thing about the hardware is that configuration for
module registers needs to be stored in a DMA buffer and gets copied
to actual registers by the hardware at the next vsync, when instructed
by a flag. This is handled by the "state" mechanism in the driver.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

1 files changed, 566 insertions, 0 deletions

diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c
new file mode 100644
index 000000000000..8039e311cb1c
--- /dev/null
+++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c
@@ -0,0 +1,566 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021-2022 Bootlin
+ * Author: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
+ */
+
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-mc.h>
+#include <media/videobuf2-vmalloc.h>
+#include <media/videobuf2-v4l2.h>
+
+#include "sun6i_isp.h"
+#include "sun6i_isp_params.h"
+#include "sun6i_isp_reg.h"
+#include "uapi/sun6i-isp-config.h"
+
+/* Params */
+
+static const struct sun6i_isp_params_config sun6i_isp_params_config_default = {
+	.modules_used = SUN6I_ISP_MODULE_BAYER,
+
+	.bayer = {
+		.offset_r	= 32,
+		.offset_gr	= 32,
+		.offset_gb	= 32,
+		.offset_b	= 32,
+
+		.gain_r		= 256,
+		.gain_gr	= 256,
+		.gain_gb	= 256,
+		.gain_b		= 256,
+
+	},
+
+	.bdnf = {
+		.in_dis_min		= 8,
+		.in_dis_max		= 16,
+
+		.coefficients_g		= { 15, 4, 1 },
+		.coefficients_rb	= { 15, 4 },
+	},
+};
+
+static void sun6i_isp_params_configure_ob(struct sun6i_isp_device *isp_dev)
+{
+	unsigned int width, height;
+
+	sun6i_isp_proc_dimensions(isp_dev, &width, &height);
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_OB_SIZE_REG,
+			     SUN6I_ISP_OB_SIZE_WIDTH(width) |
+			     SUN6I_ISP_OB_SIZE_HEIGHT(height));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_OB_VALID_REG,
+			     SUN6I_ISP_OB_VALID_WIDTH(width) |
+			     SUN6I_ISP_OB_VALID_HEIGHT(height));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_OB_SRC0_VALID_START_REG,
+			     SUN6I_ISP_OB_SRC0_VALID_START_HORZ(0) |
+			     SUN6I_ISP_OB_SRC0_VALID_START_VERT(0));
+}
+
+static void sun6i_isp_params_configure_ae(struct sun6i_isp_device *isp_dev)
+{
+	/* These are default values that need to be set to get an output. */
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_AE_CFG_REG,
+			     SUN6I_ISP_AE_CFG_LOW_BRI_TH(0xff) |
+			     SUN6I_ISP_AE_CFG_HORZ_NUM(8) |
+			     SUN6I_ISP_AE_CFG_HIGH_BRI_TH(0xf00) |
+			     SUN6I_ISP_AE_CFG_VERT_NUM(8));
+}
+
+static void
+sun6i_isp_params_configure_bayer(struct sun6i_isp_device *isp_dev,
+				 const struct sun6i_isp_params_config *config)
+{
+	const struct sun6i_isp_params_config_bayer *bayer = &config->bayer;
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_BAYER_OFFSET0_REG,
+			     SUN6I_ISP_BAYER_OFFSET0_R(bayer->offset_r) |
+			     SUN6I_ISP_BAYER_OFFSET0_GR(bayer->offset_gr));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_BAYER_OFFSET1_REG,
+			     SUN6I_ISP_BAYER_OFFSET1_GB(bayer->offset_gb) |
+			     SUN6I_ISP_BAYER_OFFSET1_B(bayer->offset_b));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_BAYER_GAIN0_REG,
+			     SUN6I_ISP_BAYER_GAIN0_R(bayer->gain_r) |
+			     SUN6I_ISP_BAYER_GAIN0_GR(bayer->gain_gr));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_BAYER_GAIN1_REG,
+			     SUN6I_ISP_BAYER_GAIN1_GB(bayer->gain_gb) |
+			     SUN6I_ISP_BAYER_GAIN1_B(bayer->gain_b));
+}
+
+static void sun6i_isp_params_configure_wb(struct sun6i_isp_device *isp_dev)
+{
+	/* These are default values that need to be set to get an output. */
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_WB_GAIN0_REG,
+			     SUN6I_ISP_WB_GAIN0_R(256) |
+			     SUN6I_ISP_WB_GAIN0_GR(256));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_WB_GAIN1_REG,
+			     SUN6I_ISP_WB_GAIN1_GB(256) |
+			     SUN6I_ISP_WB_GAIN1_B(256));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_WB_CFG_REG,
+			     SUN6I_ISP_WB_CFG_CLIP(0xfff));
+}
+
+static void sun6i_isp_params_configure_base(struct sun6i_isp_device *isp_dev)
+{
+	sun6i_isp_params_configure_ae(isp_dev);
+	sun6i_isp_params_configure_ob(isp_dev);
+	sun6i_isp_params_configure_wb(isp_dev);
+}
+
+static void
+sun6i_isp_params_configure_bdnf(struct sun6i_isp_device *isp_dev,
+				const struct sun6i_isp_params_config *config)
+{
+	const struct sun6i_isp_params_config_bdnf *bdnf = &config->bdnf;
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_BDNF_CFG_REG,
+			     SUN6I_ISP_BDNF_CFG_IN_DIS_MIN(bdnf->in_dis_min) |
+			     SUN6I_ISP_BDNF_CFG_IN_DIS_MAX(bdnf->in_dis_max));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_BDNF_COEF_RB_REG,
+			     SUN6I_ISP_BDNF_COEF_RB(0, bdnf->coefficients_rb[0]) |
+			     SUN6I_ISP_BDNF_COEF_RB(1, bdnf->coefficients_rb[1]) |
+			     SUN6I_ISP_BDNF_COEF_RB(2, bdnf->coefficients_rb[2]) |
+			     SUN6I_ISP_BDNF_COEF_RB(3, bdnf->coefficients_rb[3]) |
+			     SUN6I_ISP_BDNF_COEF_RB(4, bdnf->coefficients_rb[4]));
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_BDNF_COEF_G_REG,
+			     SUN6I_ISP_BDNF_COEF_G(0, bdnf->coefficients_g[0]) |
+			     SUN6I_ISP_BDNF_COEF_G(1, bdnf->coefficients_g[1]) |
+			     SUN6I_ISP_BDNF_COEF_G(2, bdnf->coefficients_g[2]) |
+			     SUN6I_ISP_BDNF_COEF_G(3, bdnf->coefficients_g[3]) |
+			     SUN6I_ISP_BDNF_COEF_G(4, bdnf->coefficients_g[4]) |
+			     SUN6I_ISP_BDNF_COEF_G(5, bdnf->coefficients_g[5]) |
+			     SUN6I_ISP_BDNF_COEF_G(6, bdnf->coefficients_g[6]));
+}
+
+static void
+sun6i_isp_params_configure_modules(struct sun6i_isp_device *isp_dev,
+				   const struct sun6i_isp_params_config *config)
+{
+	u32 value;
+
+	if (config->modules_used & SUN6I_ISP_MODULE_BDNF)
+		sun6i_isp_params_configure_bdnf(isp_dev, config);
+
+	if (config->modules_used & SUN6I_ISP_MODULE_BAYER)
+		sun6i_isp_params_configure_bayer(isp_dev, config);
+
+	value = sun6i_isp_load_read(isp_dev, SUN6I_ISP_MODULE_EN_REG);
+	/* Clear all modules but keep input configuration. */
+	value &= SUN6I_ISP_MODULE_EN_SRC0 | SUN6I_ISP_MODULE_EN_SRC1;
+
+	if (config->modules_used & SUN6I_ISP_MODULE_BDNF)
+		value |= SUN6I_ISP_MODULE_EN_BDNF;
+
+	/* Bayer stage is always enabled. */
+
+	sun6i_isp_load_write(isp_dev, SUN6I_ISP_MODULE_EN_REG, value);
+}
+
+void sun6i_isp_params_configure(struct sun6i_isp_device *isp_dev)
+{
+	struct sun6i_isp_params_state *state = &isp_dev->params.state;
+	unsigned long flags;
+
+	spin_lock_irqsave(&state->lock, flags);
+
+	sun6i_isp_params_configure_base(isp_dev);
+
+	/* Default config is only applied at the very first stream start. */
+	if (state->configured)
+		goto complete;
+
+	 sun6i_isp_params_configure_modules(isp_dev,
+					    &sun6i_isp_params_config_default);
+
+	state->configured = true;
+
+complete:
+	spin_unlock_irqrestore(&state->lock, flags);
+}
+
+/* State */
+
+static void sun6i_isp_params_state_cleanup(struct sun6i_isp_device *isp_dev,
+					   bool error)
+{
+	struct sun6i_isp_params_state *state = &isp_dev->params.state;
+	struct sun6i_isp_buffer *isp_buffer;
+	struct vb2_buffer *vb2_buffer;
+	unsigned long flags;
+
+	spin_lock_irqsave(&state->lock, flags);
+
+	if (state->pending) {
+		vb2_buffer = &state->pending->v4l2_buffer.vb2_buf;
+		vb2_buffer_done(vb2_buffer, error ? VB2_BUF_STATE_ERROR :
+				VB2_BUF_STATE_QUEUED);
+	}
+
+	list_for_each_entry(isp_buffer, &state->queue, list) {
+		vb2_buffer = &isp_buffer->v4l2_buffer.vb2_buf;
+		vb2_buffer_done(vb2_buffer, error ? VB2_BUF_STATE_ERROR :
+				VB2_BUF_STATE_QUEUED);
+	}
+
+	INIT_LIST_HEAD(&state->queue);
+
+	spin_unlock_irqrestore(&state->lock, flags);
+}
+
+void sun6i_isp_params_state_update(struct sun6i_isp_device *isp_dev,
+				   bool *update)
+{
+	struct sun6i_isp_params_state *state = &isp_dev->params.state;
+	struct sun6i_isp_buffer *isp_buffer;
+	struct vb2_buffer *vb2_buffer;
+	const struct sun6i_isp_params_config *config;
+	unsigned long flags;
+
+	spin_lock_irqsave(&state->lock, flags);
+
+	if (list_empty(&state->queue))
+		goto complete;
+
+	if (state->pending)
+		goto complete;
+
+	isp_buffer = list_first_entry(&state->queue, struct sun6i_isp_buffer,
+				      list);
+
+	vb2_buffer = &isp_buffer->v4l2_buffer.vb2_buf;
+	config = vb2_plane_vaddr(vb2_buffer, 0);
+
+	sun6i_isp_params_configure_modules(isp_dev, config);
+
+	list_del(&isp_buffer->list);
+
+	state->pending = isp_buffer;
+
+	if (update)
+		*update = true;
+
+complete:
+	spin_unlock_irqrestore(&state->lock, flags);
+}
+
+void sun6i_isp_params_state_complete(struct sun6i_isp_device *isp_dev)
+{
+	struct sun6i_isp_params_state *state = &isp_dev->params.state;
+	struct sun6i_isp_buffer *isp_buffer;
+	struct vb2_buffer *vb2_buffer;
+	unsigned long flags;
+
+	spin_lock_irqsave(&state->lock, flags);
+
+	if (!state->pending)
+		goto complete;
+
+	isp_buffer = state->pending;
+	vb2_buffer = &isp_buffer->v4l2_buffer.vb2_buf;
+
+	vb2_buffer->timestamp = ktime_get_ns();
+
+	/* Parameters will be applied starting from the next frame. */
+	isp_buffer->v4l2_buffer.sequence = isp_dev->capture.state.sequence + 1;
+
+	vb2_buffer_done(vb2_buffer, VB2_BUF_STATE_DONE);
+
+	state->pending = NULL;
+
+complete:
+	spin_unlock_irqrestore(&state->lock, flags);
+}
+
+/* Queue */
+
+static int sun6i_isp_params_queue_setup(struct vb2_queue *queue,
+					unsigned int *buffers_count,
+					unsigned int *planes_count,
+					unsigned int sizes[],
+					struct device *alloc_devs[])
+{
+	struct sun6i_isp_device *isp_dev = vb2_get_drv_priv(queue);
+	unsigned int size = isp_dev->params.format.fmt.meta.buffersize;
+
+	if (*planes_count)
+		return sizes[0] < size ? -EINVAL : 0;
+
+	*planes_count = 1;
+	sizes[0] = size;
+
+	return 0;
+}
+
+static int sun6i_isp_params_buffer_prepare(struct vb2_buffer *vb2_buffer)
+{
+	struct sun6i_isp_device *isp_dev =
+		vb2_get_drv_priv(vb2_buffer->vb2_queue);
+	struct v4l2_device *v4l2_dev = &isp_dev->v4l2.v4l2_dev;
+	unsigned int size = isp_dev->params.format.fmt.meta.buffersize;
+
+	if (vb2_plane_size(vb2_buffer, 0) < size) {
+		v4l2_err(v4l2_dev, "buffer too small (%lu < %u)\n",
+			 vb2_plane_size(vb2_buffer, 0), size);
+		return -EINVAL;
+	}
+
+	vb2_set_plane_payload(vb2_buffer, 0, size);
+
+	return 0;
+}
+
+static void sun6i_isp_params_buffer_queue(struct vb2_buffer *vb2_buffer)
+{
+	struct sun6i_isp_device *isp_dev =
+		vb2_get_drv_priv(vb2_buffer->vb2_queue);
+	struct sun6i_isp_params_state *state = &isp_dev->params.state;
+	struct vb2_v4l2_buffer *v4l2_buffer = to_vb2_v4l2_buffer(vb2_buffer);
+	struct sun6i_isp_buffer *isp_buffer =
+		container_of(v4l2_buffer, struct sun6i_isp_buffer, v4l2_buffer);
+	bool capture_streaming = isp_dev->capture.state.streaming;
+	unsigned long flags;
+
+	spin_lock_irqsave(&state->lock, flags);
+	list_add_tail(&isp_buffer->list, &state->queue);
+	spin_unlock_irqrestore(&state->lock, flags);
+
+	if (state->streaming && capture_streaming)
+		sun6i_isp_state_update(isp_dev, false);
+}
+
+static int sun6i_isp_params_start_streaming(struct vb2_queue *queue,
+					    unsigned int count)
+{
+	struct sun6i_isp_device *isp_dev = vb2_get_drv_priv(queue);
+	struct sun6i_isp_params_state *state = &isp_dev->params.state;
+	bool capture_streaming = isp_dev->capture.state.streaming;
+
+	state->streaming = true;
+
+	/*
+	 * Update the state as soon as possible if capture is streaming,
+	 * otherwise it will be applied when capture starts streaming.
+	 */
+
+	if (capture_streaming)
+		sun6i_isp_state_update(isp_dev, false);
+
+	return 0;
+}
+
+static void sun6i_isp_params_stop_streaming(struct vb2_queue *queue)
+{
+	struct sun6i_isp_device *isp_dev = vb2_get_drv_priv(queue);
+	struct sun6i_isp_params_state *state = &isp_dev->params.state;
+
+	state->streaming = false;
+	sun6i_isp_params_state_cleanup(isp_dev, true);
+}
+
+static const struct vb2_ops sun6i_isp_params_queue_ops = {
+	.queue_setup		= sun6i_isp_params_queue_setup,
+	.buf_prepare		= sun6i_isp_params_buffer_prepare,
+	.buf_queue		= sun6i_isp_params_buffer_queue,
+	.start_streaming	= sun6i_isp_params_start_streaming,
+	.stop_streaming		= sun6i_isp_params_stop_streaming,
+	.wait_prepare		= vb2_ops_wait_prepare,
+	.wait_finish		= vb2_ops_wait_finish,
+};
+
+/* Video Device */
+
+static int sun6i_isp_params_querycap(struct file *file, void *private,
+				     struct v4l2_capability *capability)
+{
+	struct sun6i_isp_device *isp_dev = video_drvdata(file);
+	struct video_device *video_dev = &isp_dev->params.video_dev;
+
+	strscpy(capability->driver, SUN6I_ISP_NAME, sizeof(capability->driver));
+	strscpy(capability->card, video_dev->name, sizeof(capability->card));
+	snprintf(capability->bus_info, sizeof(capability->bus_info),
+		 "platform:%s", dev_name(isp_dev->dev));
+
+	return 0;
+}
+
+static int sun6i_isp_params_enum_fmt(struct file *file, void *private,
+				     struct v4l2_fmtdesc *fmtdesc)
+{
+	struct sun6i_isp_device *isp_dev = video_drvdata(file);
+	struct v4l2_meta_format *params_format =
+		&isp_dev->params.format.fmt.meta;
+
+	if (fmtdesc->index > 0)
+		return -EINVAL;
+
+	fmtdesc->pixelformat = params_format->dataformat;
+
+	return 0;
+}
+
+static int sun6i_isp_params_g_fmt(struct file *file, void *private,
+				  struct v4l2_format *format)
+{
+	struct sun6i_isp_device *isp_dev = video_drvdata(file);
+
+	*format = isp_dev->params.format;
+
+	return 0;
+}
+
+static const struct v4l2_ioctl_ops sun6i_isp_params_ioctl_ops = {
+	.vidioc_querycap		= sun6i_isp_params_querycap,
+
+	.vidioc_enum_fmt_meta_out	= sun6i_isp_params_enum_fmt,
+	.vidioc_g_fmt_meta_out		= sun6i_isp_params_g_fmt,
+	.vidioc_s_fmt_meta_out		= sun6i_isp_params_g_fmt,
+	.vidioc_try_fmt_meta_out	= sun6i_isp_params_g_fmt,
+
+	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
+	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
+	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
+	.vidioc_querybuf		= vb2_ioctl_querybuf,
+	.vidioc_expbuf			= vb2_ioctl_expbuf,
+	.vidioc_qbuf			= vb2_ioctl_qbuf,
+	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
+	.vidioc_streamon		= vb2_ioctl_streamon,
+	.vidioc_streamoff		= vb2_ioctl_streamoff,
+};
+
+static const struct v4l2_file_operations sun6i_isp_params_fops = {
+	.owner		= THIS_MODULE,
+	.unlocked_ioctl	= video_ioctl2,
+	.open		= v4l2_fh_open,
+	.release	= vb2_fop_release,
+	.mmap		= vb2_fop_mmap,
+	.poll		= vb2_fop_poll,
+};
+
+/* Params */
+
+int sun6i_isp_params_setup(struct sun6i_isp_device *isp_dev)
+{
+	struct sun6i_isp_params *params = &isp_dev->params;
+	struct sun6i_isp_params_state *state = &params->state;
+	struct v4l2_device *v4l2_dev = &isp_dev->v4l2.v4l2_dev;
+	struct v4l2_subdev *proc_subdev = &isp_dev->proc.subdev;
+	struct video_device *video_dev = &params->video_dev;
+	struct vb2_queue *queue = &isp_dev->params.queue;
+	struct media_pad *pad = &isp_dev->params.pad;
+	struct v4l2_format *format = &isp_dev->params.format;
+	struct v4l2_meta_format *params_format = &format->fmt.meta;
+	int ret;
+
+	/* State */
+
+	INIT_LIST_HEAD(&state->queue);
+	spin_lock_init(&state->lock);
+
+	/* Media Pads */
+
+	pad->flags = MEDIA_PAD_FL_SOURCE | MEDIA_PAD_FL_MUST_CONNECT;
+
+	ret = media_entity_pads_init(&video_dev->entity, 1, pad);
+	if (ret)
+		goto error_mutex;
+
+	/* Queue */
+
+	mutex_init(&params->lock);
+
+	queue->type = V4L2_BUF_TYPE_META_OUTPUT;
+	queue->io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
+	queue->buf_struct_size = sizeof(struct sun6i_isp_buffer);
+	queue->ops = &sun6i_isp_params_queue_ops;
+	queue->mem_ops = &vb2_vmalloc_memops;
+	queue->min_buffers_needed = 1;
+	queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+	queue->lock = &params->lock;
+	queue->dev = isp_dev->dev;
+	queue->drv_priv = isp_dev;
+
+	ret = vb2_queue_init(queue);
+	if (ret) {
+		v4l2_err(v4l2_dev, "failed to initialize vb2 queue: %d\n", ret);
+		goto error_media_entity;
+	}
+
+	/* V4L2 Format */
+
+	format->type = queue->type;
+	params_format->dataformat = V4L2_META_FMT_SUN6I_ISP_PARAMS;
+	params_format->buffersize = sizeof(struct sun6i_isp_params_config);
+
+	/* Video Device */
+
+	strscpy(video_dev->name, SUN6I_ISP_PARAMS_NAME,
+		sizeof(video_dev->name));
+	video_dev->device_caps = V4L2_CAP_META_OUTPUT | V4L2_CAP_STREAMING;
+	video_dev->vfl_dir = VFL_DIR_TX;
+	video_dev->release = video_device_release_empty;
+	video_dev->fops = &sun6i_isp_params_fops;
+	video_dev->ioctl_ops = &sun6i_isp_params_ioctl_ops;
+	video_dev->v4l2_dev = v4l2_dev;
+	video_dev->queue = queue;
+	video_dev->lock = &params->lock;
+
+	video_set_drvdata(video_dev, isp_dev);
+
+	ret = video_register_device(video_dev, VFL_TYPE_VIDEO, -1);
+	if (ret) {
+		v4l2_err(v4l2_dev, "failed to register video device: %d\n",
+			 ret);
+		goto error_media_entity;
+	}
+
+	/* Media Pad Link */
+
+	ret = media_create_pad_link(&video_dev->entity, 0,
+				    &proc_subdev->entity,
+				    SUN6I_ISP_PROC_PAD_SINK_PARAMS,
+				    MEDIA_LNK_FL_ENABLED |
+				    MEDIA_LNK_FL_IMMUTABLE);
+	if (ret < 0) {
+		v4l2_err(v4l2_dev, "failed to create %s:%u -> %s:%u link\n",
+			 video_dev->entity.name, 0, proc_subdev->entity.name,
+			 SUN6I_ISP_PROC_PAD_SINK_PARAMS);
+		goto error_video_device;
+	}
+
+	return 0;
+
+error_video_device:
+	vb2_video_unregister_device(video_dev);
+
+error_media_entity:
+	media_entity_cleanup(&video_dev->entity);
+
+error_mutex:
+	mutex_destroy(&params->lock);
+
+	return ret;
+}
+
+void sun6i_isp_params_cleanup(struct sun6i_isp_device *isp_dev)
+{
+	struct sun6i_isp_params *params = &isp_dev->params;
+	struct video_device *video_dev = &params->video_dev;
+
+	vb2_video_unregister_device(video_dev);
+	media_entity_cleanup(&video_dev->entity);
+	mutex_destroy(&params->lock);
+}