[media] media: Support Intersil/Techwell TW686x-based video capture cards

This commit introduces the support for the Techwell TW686x video
capture IC. This hardware supports a few DMA modes, including
scatter-gather and frame (contiguous).

This commit makes little use of the DMA engine and instead has
a memcpy based implementation. DMA frame and scatter-gather modes
support may be added in the future.

Currently supported chips:
- TW6864 (4 video channels),
- TW6865 (4 video channels, not tested, second generation chip),
- TW6868 (8 video channels but only 4 first channels using
           built-in video decoder are supported, not tested),
- TW6869 (8 video channels, second generation chip).

[mchehab@osg.samsung.com: make checkpatch happy by using "unsigned int"
  instead  of just "unsigned"]
Cc: Krzysztof Halasa <khalasa@piap.pl>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Hans Verkuil <hans.verkuil@cisco.com>

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

1 files changed, 927 insertions, 0 deletions

diff --git a/drivers/media/pci/tw686x/tw686x-video.c b/drivers/media/pci/tw686x/tw686x-video.c
new file mode 100644
index 000000000000..35ad8e650717
--- /dev/null
+++ b/drivers/media/pci/tw686x/tw686x-video.c
@@ -0,0 +1,927 @@
+/*
+ * Copyright (C) 2015 VanguardiaSur - www.vanguardiasur.com.ar
+ *
+ * Based on original driver by Krzysztof Ha?asa:
+ * Copyright (C) 2015 Industrial Research Institute for Automation
+ * and Measurements PIAP
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <media/v4l2-common.h>
+#include <media/v4l2-event.h>
+#include <media/videobuf2-vmalloc.h>
+#include "tw686x.h"
+#include "tw686x-regs.h"
+
+#define TW686X_INPUTS_PER_CH		4
+#define TW686X_VIDEO_WIDTH		720
+#define TW686X_VIDEO_HEIGHT(id)		((id & V4L2_STD_625_50) ? 576 : 480)
+
+static const struct tw686x_format formats[] = {
+	{
+		.fourcc = V4L2_PIX_FMT_UYVY,
+		.mode = 0,
+		.depth = 16,
+	}, {
+		.fourcc = V4L2_PIX_FMT_RGB565,
+		.mode = 5,
+		.depth = 16,
+	}, {
+		.fourcc = V4L2_PIX_FMT_YUYV,
+		.mode = 6,
+		.depth = 16,
+	}
+};
+
+static unsigned int tw686x_fields_map(v4l2_std_id std, unsigned int fps)
+{
+	static const unsigned int map[15] = {
+		0x00000000, 0x00000001, 0x00004001, 0x00104001, 0x00404041,
+		0x01041041, 0x01104411, 0x01111111, 0x04444445, 0x04511445,
+		0x05145145, 0x05151515, 0x05515455, 0x05551555, 0x05555555
+	};
+
+	static const unsigned int std_625_50[26] = {
+		0, 1, 1, 2,  3,  3,  4,  4,  5,  5,  6,  7,  7,
+		   8, 8, 9, 10, 10, 11, 11, 12, 13, 13, 14, 14, 0
+	};
+
+	static const unsigned int std_525_60[31] = {
+		0, 1, 1, 1, 2,  2,  3,  3,  4,  4,  5,  5,  6,  6, 7, 7,
+		   8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 0, 0
+	};
+
+	unsigned int i =
+		(std & V4L2_STD_625_50) ? std_625_50[fps] : std_525_60[fps];
+
+	return map[i];
+}
+
+static void tw686x_set_framerate(struct tw686x_video_channel *vc,
+				 unsigned int fps)
+{
+	unsigned int map;
+
+	if (vc->fps == fps)
+		return;
+
+	map = tw686x_fields_map(vc->video_standard, fps) << 1;
+	map |= map << 1;
+	if (map > 0)
+		map |= BIT(31);
+	reg_write(vc->dev, VIDEO_FIELD_CTRL[vc->ch], map);
+	vc->fps = fps;
+}
+
+static const struct tw686x_format *format_by_fourcc(unsigned int fourcc)
+{
+	unsigned int cnt;
+
+	for (cnt = 0; cnt < ARRAY_SIZE(formats); cnt++)
+		if (formats[cnt].fourcc == fourcc)
+			return &formats[cnt];
+	return NULL;
+}
+
+static int tw686x_queue_setup(struct vb2_queue *vq,
+			      unsigned int *nbuffers, unsigned int *nplanes,
+			      unsigned int sizes[], void *alloc_ctxs[])
+{
+	struct tw686x_video_channel *vc = vb2_get_drv_priv(vq);
+	unsigned int szimage =
+		(vc->width * vc->height * vc->format->depth) >> 3;
+
+	/*
+	 * Let's request at least three buffers: two for the
+	 * DMA engine and one for userspace.
+	 */
+	if (vq->num_buffers + *nbuffers < 3)
+		*nbuffers = 3 - vq->num_buffers;
+
+	if (*nplanes) {
+		if (*nplanes != 1 || sizes[0] < szimage)
+			return -EINVAL;
+		return 0;
+	}
+
+	sizes[0] = szimage;
+	*nplanes = 1;
+	return 0;
+}
+
+static void tw686x_buf_queue(struct vb2_buffer *vb)
+{
+	struct tw686x_video_channel *vc = vb2_get_drv_priv(vb->vb2_queue);
+	struct tw686x_dev *dev = vc->dev;
+	struct pci_dev *pci_dev;
+	unsigned long flags;
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct tw686x_v4l2_buf *buf =
+		container_of(vbuf, struct tw686x_v4l2_buf, vb);
+
+	/* Check device presence */
+	spin_lock_irqsave(&dev->lock, flags);
+	pci_dev = dev->pci_dev;
+	spin_unlock_irqrestore(&dev->lock, flags);
+	if (!pci_dev) {
+		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+		return;
+	}
+
+	spin_lock_irqsave(&vc->qlock, flags);
+	list_add_tail(&buf->list, &vc->vidq_queued);
+	spin_unlock_irqrestore(&vc->qlock, flags);
+}
+
+/*
+ * We can call this even when alloc_dma failed for the given channel
+ */
+static void tw686x_free_dma(struct tw686x_video_channel *vc, unsigned int pb)
+{
+	struct tw686x_dma_desc *desc = &vc->dma_descs[pb];
+	struct tw686x_dev *dev = vc->dev;
+	struct pci_dev *pci_dev;
+	unsigned long flags;
+
+	/* Check device presence. Shouldn't really happen! */
+	spin_lock_irqsave(&dev->lock, flags);
+	pci_dev = dev->pci_dev;
+	spin_unlock_irqrestore(&dev->lock, flags);
+	if (!pci_dev) {
+		WARN(1, "trying to deallocate on missing device\n");
+		return;
+	}
+
+	if (desc->virt) {
+		pci_free_consistent(dev->pci_dev, desc->size,
+				    desc->virt, desc->phys);
+		desc->virt = NULL;
+	}
+}
+
+static int tw686x_alloc_dma(struct tw686x_video_channel *vc, unsigned int pb)
+{
+	struct tw686x_dev *dev = vc->dev;
+	u32 reg = pb ? VDMA_B_ADDR[vc->ch] : VDMA_P_ADDR[vc->ch];
+	unsigned int len;
+	void *virt;
+
+	WARN(vc->dma_descs[pb].virt,
+	     "Allocating buffer but previous still here\n");
+
+	len = (vc->width * vc->height * vc->format->depth) >> 3;
+	virt = pci_alloc_consistent(dev->pci_dev, len,
+				    &vc->dma_descs[pb].phys);
+	if (!virt) {
+		v4l2_err(&dev->v4l2_dev,
+			 "dma%d: unable to allocate %s-buffer\n",
+			 vc->ch, pb ? "B" : "P");
+		return -ENOMEM;
+	}
+	vc->dma_descs[pb].size = len;
+	vc->dma_descs[pb].virt = virt;
+	reg_write(dev, reg, vc->dma_descs[pb].phys);
+
+	return 0;
+}
+
+static void tw686x_buffer_refill(struct tw686x_video_channel *vc,
+				 unsigned int pb)
+{
+	struct tw686x_v4l2_buf *buf;
+
+	while (!list_empty(&vc->vidq_queued)) {
+
+		buf = list_first_entry(&vc->vidq_queued,
+			struct tw686x_v4l2_buf, list);
+		list_del(&buf->list);
+
+		vc->curr_bufs[pb] = buf;
+		return;
+	}
+	vc->curr_bufs[pb] = NULL;
+}
+
+static void tw686x_clear_queue(struct tw686x_video_channel *vc,
+			       enum vb2_buffer_state state)
+{
+	unsigned int pb;
+
+	while (!list_empty(&vc->vidq_queued)) {
+		struct tw686x_v4l2_buf *buf;
+
+		buf = list_first_entry(&vc->vidq_queued,
+			struct tw686x_v4l2_buf, list);
+		list_del(&buf->list);
+		vb2_buffer_done(&buf->vb.vb2_buf, state);
+	}
+
+	for (pb = 0; pb < 2; pb++) {
+		if (vc->curr_bufs[pb])
+			vb2_buffer_done(&vc->curr_bufs[pb]->vb.vb2_buf, state);
+		vc->curr_bufs[pb] = NULL;
+	}
+}
+
+static int tw686x_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct tw686x_video_channel *vc = vb2_get_drv_priv(vq);
+	struct tw686x_dev *dev = vc->dev;
+	struct pci_dev *pci_dev;
+	unsigned long flags;
+	int pb, err;
+
+	/* Check device presence */
+	spin_lock_irqsave(&dev->lock, flags);
+	pci_dev = dev->pci_dev;
+	spin_unlock_irqrestore(&dev->lock, flags);
+	if (!pci_dev) {
+		err = -ENODEV;
+		goto err_clear_queue;
+	}
+
+	spin_lock_irqsave(&vc->qlock, flags);
+
+	/* Sanity check */
+	if (!vc->dma_descs[0].virt || !vc->dma_descs[1].virt) {
+		spin_unlock_irqrestore(&vc->qlock, flags);
+		v4l2_err(&dev->v4l2_dev,
+			 "video%d: refusing to start without DMA buffers\n",
+			 vc->num);
+		err = -ENOMEM;
+		goto err_clear_queue;
+	}
+
+	for (pb = 0; pb < 2; pb++)
+		tw686x_buffer_refill(vc, pb);
+	spin_unlock_irqrestore(&vc->qlock, flags);
+
+	vc->sequence = 0;
+	vc->pb = 0;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	tw686x_enable_channel(dev, vc->ch);
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	mod_timer(&dev->dma_delay_timer, jiffies + msecs_to_jiffies(100));
+
+	return 0;
+
+err_clear_queue:
+	spin_lock_irqsave(&vc->qlock, flags);
+	tw686x_clear_queue(vc, VB2_BUF_STATE_QUEUED);
+	spin_unlock_irqrestore(&vc->qlock, flags);
+	return err;
+}
+
+static void tw686x_stop_streaming(struct vb2_queue *vq)
+{
+	struct tw686x_video_channel *vc = vb2_get_drv_priv(vq);
+	struct tw686x_dev *dev = vc->dev;
+	struct pci_dev *pci_dev;
+	unsigned long flags;
+
+	/* Check device presence */
+	spin_lock_irqsave(&dev->lock, flags);
+	pci_dev = dev->pci_dev;
+	spin_unlock_irqrestore(&dev->lock, flags);
+	if (pci_dev)
+		tw686x_disable_channel(dev, vc->ch);
+
+	spin_lock_irqsave(&vc->qlock, flags);
+	tw686x_clear_queue(vc, VB2_BUF_STATE_ERROR);
+	spin_unlock_irqrestore(&vc->qlock, flags);
+}
+
+static int tw686x_buf_prepare(struct vb2_buffer *vb)
+{
+	struct tw686x_video_channel *vc = vb2_get_drv_priv(vb->vb2_queue);
+	unsigned int size =
+		(vc->width * vc->height * vc->format->depth) >> 3;
+
+	if (vb2_plane_size(vb, 0) < size)
+		return -EINVAL;
+	vb2_set_plane_payload(vb, 0, size);
+	return 0;
+}
+
+static struct vb2_ops tw686x_video_qops = {
+	.queue_setup		= tw686x_queue_setup,
+	.buf_queue		= tw686x_buf_queue,
+	.buf_prepare		= tw686x_buf_prepare,
+	.start_streaming	= tw686x_start_streaming,
+	.stop_streaming		= tw686x_stop_streaming,
+	.wait_prepare		= vb2_ops_wait_prepare,
+	.wait_finish		= vb2_ops_wait_finish,
+};
+
+static int tw686x_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct tw686x_video_channel *vc;
+	struct tw686x_dev *dev;
+	unsigned int ch;
+
+	vc = container_of(ctrl->handler, struct tw686x_video_channel,
+			  ctrl_handler);
+	dev = vc->dev;
+	ch = vc->ch;
+
+	switch (ctrl->id) {
+	case V4L2_CID_BRIGHTNESS:
+		reg_write(dev, BRIGHT[ch], ctrl->val & 0xff);
+		return 0;
+
+	case V4L2_CID_CONTRAST:
+		reg_write(dev, CONTRAST[ch], ctrl->val);
+		return 0;
+
+	case V4L2_CID_SATURATION:
+		reg_write(dev, SAT_U[ch], ctrl->val);
+		reg_write(dev, SAT_V[ch], ctrl->val);
+		return 0;
+
+	case V4L2_CID_HUE:
+		reg_write(dev, HUE[ch], ctrl->val & 0xff);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static const struct v4l2_ctrl_ops ctrl_ops = {
+	.s_ctrl = tw686x_s_ctrl,
+};
+
+static int tw686x_g_fmt_vid_cap(struct file *file, void *priv,
+				struct v4l2_format *f)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+
+	f->fmt.pix.width = vc->width;
+	f->fmt.pix.height = vc->height;
+	f->fmt.pix.field = V4L2_FIELD_INTERLACED;
+	f->fmt.pix.pixelformat = vc->format->fourcc;
+	f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
+	f->fmt.pix.bytesperline = (f->fmt.pix.width * vc->format->depth) / 8;
+	f->fmt.pix.sizeimage = f->fmt.pix.height * f->fmt.pix.bytesperline;
+	return 0;
+}
+
+static int tw686x_try_fmt_vid_cap(struct file *file, void *priv,
+				  struct v4l2_format *f)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+	unsigned int video_height = TW686X_VIDEO_HEIGHT(vc->video_standard);
+	const struct tw686x_format *format;
+
+	format = format_by_fourcc(f->fmt.pix.pixelformat);
+	if (!format) {
+		format = &formats[0];
+		f->fmt.pix.pixelformat = format->fourcc;
+	}
+
+	if (f->fmt.pix.width <= TW686X_VIDEO_WIDTH / 2)
+		f->fmt.pix.width = TW686X_VIDEO_WIDTH / 2;
+	else
+		f->fmt.pix.width = TW686X_VIDEO_WIDTH;
+
+	if (f->fmt.pix.height <= video_height / 2)
+		f->fmt.pix.height = video_height / 2;
+	else
+		f->fmt.pix.height = video_height;
+
+	f->fmt.pix.bytesperline = (f->fmt.pix.width * format->depth) / 8;
+	f->fmt.pix.sizeimage = f->fmt.pix.height * f->fmt.pix.bytesperline;
+	f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
+	f->fmt.pix.field = V4L2_FIELD_INTERLACED;
+
+	return 0;
+}
+
+static int tw686x_s_fmt_vid_cap(struct file *file, void *priv,
+				struct v4l2_format *f)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+	u32 val, width, line_width, height;
+	unsigned long bitsperframe;
+	int err, pb;
+
+	if (vb2_is_busy(&vc->vidq))
+		return -EBUSY;
+
+	bitsperframe = vc->width * vc->height * vc->format->depth;
+	err = tw686x_try_fmt_vid_cap(file, priv, f);
+	if (err)
+		return err;
+
+	vc->format = format_by_fourcc(f->fmt.pix.pixelformat);
+	vc->width = f->fmt.pix.width;
+	vc->height = f->fmt.pix.height;
+
+	/* We need new DMA buffers if the framesize has changed */
+	if (bitsperframe != vc->width * vc->height * vc->format->depth) {
+		for (pb = 0; pb < 2; pb++)
+			tw686x_free_dma(vc, pb);
+
+		for (pb = 0; pb < 2; pb++) {
+			err = tw686x_alloc_dma(vc, pb);
+			if (err) {
+				if (pb > 0)
+					tw686x_free_dma(vc, 0);
+				return err;
+			}
+		}
+	}
+
+	val = reg_read(vc->dev, VDMA_CHANNEL_CONFIG[vc->ch]);
+
+	if (vc->width <= TW686X_VIDEO_WIDTH / 2)
+		val |= BIT(23);
+	else
+		val &= ~BIT(23);
+
+	if (vc->height <= TW686X_VIDEO_HEIGHT(vc->video_standard) / 2)
+		val |= BIT(24);
+	else
+		val &= ~BIT(24);
+
+	val &= ~(0x7 << 20);
+	val |= vc->format->mode << 20;
+	reg_write(vc->dev, VDMA_CHANNEL_CONFIG[vc->ch], val);
+
+	/* Program the DMA frame size */
+	width = (vc->width * 2) & 0x7ff;
+	height = vc->height / 2;
+	line_width = (vc->width * 2) & 0x7ff;
+	val = (height << 22) | (line_width << 11)  | width;
+	reg_write(vc->dev, VDMA_WHP[vc->ch], val);
+	return 0;
+}
+
+static int tw686x_querycap(struct file *file, void *priv,
+			   struct v4l2_capability *cap)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+	struct tw686x_dev *dev = vc->dev;
+
+	strlcpy(cap->driver, "tw686x", sizeof(cap->driver));
+	strlcpy(cap->card, dev->name, sizeof(cap->card));
+	snprintf(cap->bus_info, sizeof(cap->bus_info),
+		 "PCI:%s", pci_name(dev->pci_dev));
+	cap->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING |
+			   V4L2_CAP_READWRITE;
+	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
+	return 0;
+}
+
+static int tw686x_s_std(struct file *file, void *priv, v4l2_std_id id)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+	struct v4l2_format f;
+	u32 val, ret;
+
+	if (vc->video_standard == id)
+		return 0;
+
+	if (vb2_is_busy(&vc->vidq))
+		return -EBUSY;
+
+	if (id & V4L2_STD_NTSC)
+		val = 0;
+	else if (id & V4L2_STD_PAL)
+		val = 1;
+	else if (id & V4L2_STD_SECAM)
+		val = 2;
+	else if (id & V4L2_STD_NTSC_443)
+		val = 3;
+	else if (id & V4L2_STD_PAL_M)
+		val = 4;
+	else if (id & V4L2_STD_PAL_Nc)
+		val = 5;
+	else if (id & V4L2_STD_PAL_60)
+		val = 6;
+	else
+		return -EINVAL;
+
+	vc->video_standard = id;
+	reg_write(vc->dev, SDT[vc->ch], val);
+
+	val = reg_read(vc->dev, VIDEO_CONTROL1);
+	if (id & V4L2_STD_625_50)
+		val |= (1 << (SYS_MODE_DMA_SHIFT + vc->ch));
+	else
+		val &= ~(1 << (SYS_MODE_DMA_SHIFT + vc->ch));
+	reg_write(vc->dev, VIDEO_CONTROL1, val);
+
+	/*
+	 * Adjust format after V4L2_STD_525_60/V4L2_STD_625_50 change,
+	 * calling g_fmt and s_fmt will sanitize the height
+	 * according to the standard.
+	 */
+	ret = tw686x_g_fmt_vid_cap(file, priv, &f);
+	if (!ret)
+		tw686x_s_fmt_vid_cap(file, priv, &f);
+	return 0;
+}
+
+static int tw686x_querystd(struct file *file, void *priv, v4l2_std_id *std)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+	struct tw686x_dev *dev = vc->dev;
+	unsigned int old_std, detected_std = 0;
+	unsigned long end;
+
+	if (vb2_is_streaming(&vc->vidq))
+		return -EBUSY;
+
+	/* Enable and start standard detection */
+	old_std = reg_read(dev, SDT[vc->ch]);
+	reg_write(dev, SDT[vc->ch], 0x7);
+	reg_write(dev, SDT_EN[vc->ch], 0xff);
+
+	end = jiffies + msecs_to_jiffies(500);
+	while (time_is_after_jiffies(end)) {
+
+		detected_std = reg_read(dev, SDT[vc->ch]);
+		if (!(detected_std & BIT(7)))
+			break;
+		msleep(100);
+	}
+	reg_write(dev, SDT[vc->ch], old_std);
+
+	/* Exit if still busy */
+	if (detected_std & BIT(7))
+		return 0;
+
+	detected_std = (detected_std >> 4) & 0x7;
+	switch (detected_std) {
+	case TW686X_STD_NTSC_M:
+		*std &= V4L2_STD_NTSC;
+		break;
+	case TW686X_STD_NTSC_443:
+		*std &= V4L2_STD_NTSC_443;
+		break;
+	case TW686X_STD_PAL_M:
+		*std &= V4L2_STD_PAL_M;
+		break;
+	case TW686X_STD_PAL_60:
+		*std &= V4L2_STD_PAL_60;
+		break;
+	case TW686X_STD_PAL:
+		*std &= V4L2_STD_PAL;
+		break;
+	case TW686X_STD_PAL_CN:
+		*std &= V4L2_STD_PAL_Nc;
+		break;
+	case TW686X_STD_SECAM:
+		*std &= V4L2_STD_SECAM;
+		break;
+	default:
+		*std = 0;
+	}
+	return 0;
+}
+
+static int tw686x_g_std(struct file *file, void *priv, v4l2_std_id *id)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+
+	*id = vc->video_standard;
+	return 0;
+}
+
+static int tw686x_enum_fmt_vid_cap(struct file *file, void *priv,
+				   struct v4l2_fmtdesc *f)
+{
+	if (f->index >= ARRAY_SIZE(formats))
+		return -EINVAL;
+	f->pixelformat = formats[f->index].fourcc;
+	return 0;
+}
+
+static int tw686x_s_input(struct file *file, void *priv, unsigned int i)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+	u32 val;
+
+	if (i >= TW686X_INPUTS_PER_CH)
+		return -EINVAL;
+	if (i == vc->input)
+		return 0;
+	/*
+	 * Not sure we are able to support on the fly input change
+	 */
+	if (vb2_is_busy(&vc->vidq))
+		return -EBUSY;
+
+	vc->input = i;
+
+	val = reg_read(vc->dev, VDMA_CHANNEL_CONFIG[vc->ch]);
+	val &= ~(0x3 << 30);
+	val |= i << 30;
+	reg_write(vc->dev, VDMA_CHANNEL_CONFIG[vc->ch], val);
+	return 0;
+}
+
+static int tw686x_g_input(struct file *file, void *priv, unsigned int *i)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+
+	*i = vc->input;
+	return 0;
+}
+
+static int tw686x_enum_input(struct file *file, void *priv,
+			     struct v4l2_input *i)
+{
+	struct tw686x_video_channel *vc = video_drvdata(file);
+	unsigned int vidstat;
+
+	if (i->index >= TW686X_INPUTS_PER_CH)
+		return -EINVAL;
+
+	snprintf(i->name, sizeof(i->name), "Composite%d", i->index);
+	i->type = V4L2_INPUT_TYPE_CAMERA;
+	i->std = vc->device->tvnorms;
+	i->capabilities = V4L2_IN_CAP_STD;
+
+	vidstat = reg_read(vc->dev, VIDSTAT[vc->ch]);
+	i->status = 0;
+	if (vidstat & TW686X_VIDSTAT_VDLOSS)
+		i->status |= V4L2_IN_ST_NO_SIGNAL;
+	if (!(vidstat & TW686X_VIDSTAT_HLOCK))
+		i->status |= V4L2_IN_ST_NO_H_LOCK;
+
+	return 0;
+}
+
+const struct v4l2_file_operations tw686x_video_fops = {
+	.owner		= THIS_MODULE,
+	.open		= v4l2_fh_open,
+	.unlocked_ioctl	= video_ioctl2,
+	.release	= vb2_fop_release,
+	.poll		= vb2_fop_poll,
+	.read		= vb2_fop_read,
+	.mmap		= vb2_fop_mmap,
+};
+
+const struct v4l2_ioctl_ops tw686x_video_ioctl_ops = {
+	.vidioc_querycap		= tw686x_querycap,
+	.vidioc_g_fmt_vid_cap		= tw686x_g_fmt_vid_cap,
+	.vidioc_s_fmt_vid_cap		= tw686x_s_fmt_vid_cap,
+	.vidioc_enum_fmt_vid_cap	= tw686x_enum_fmt_vid_cap,
+	.vidioc_try_fmt_vid_cap		= tw686x_try_fmt_vid_cap,
+
+	.vidioc_querystd		= tw686x_querystd,
+	.vidioc_g_std			= tw686x_g_std,
+	.vidioc_s_std			= tw686x_s_std,
+
+	.vidioc_enum_input		= tw686x_enum_input,
+	.vidioc_g_input			= tw686x_g_input,
+	.vidioc_s_input			= tw686x_s_input,
+
+	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
+	.vidioc_querybuf		= vb2_ioctl_querybuf,
+	.vidioc_qbuf			= vb2_ioctl_qbuf,
+	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
+	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
+	.vidioc_streamon		= vb2_ioctl_streamon,
+	.vidioc_streamoff		= vb2_ioctl_streamoff,
+	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
+
+	.vidioc_log_status		= v4l2_ctrl_log_status,
+	.vidioc_subscribe_event		= v4l2_ctrl_subscribe_event,
+	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
+};
+
+static void tw686x_buffer_copy(struct tw686x_video_channel *vc,
+			       unsigned int pb, struct vb2_v4l2_buffer *vb)
+{
+	struct tw686x_dma_desc *desc = &vc->dma_descs[pb];
+	struct vb2_buffer *vb2_buf = &vb->vb2_buf;
+
+	vb->field = V4L2_FIELD_INTERLACED;
+	vb->sequence = vc->sequence++;
+
+	memcpy(vb2_plane_vaddr(vb2_buf, 0), desc->virt, desc->size);
+	vb2_buf->timestamp = ktime_get_ns();
+	vb2_buffer_done(vb2_buf, VB2_BUF_STATE_DONE);
+}
+
+void tw686x_video_irq(struct tw686x_dev *dev, unsigned long requests,
+		      unsigned int pb_status, unsigned int fifo_status,
+		      unsigned int *reset_ch)
+{
+	struct tw686x_video_channel *vc;
+	struct vb2_v4l2_buffer *vb;
+	unsigned long flags;
+	unsigned int ch, pb;
+
+	for_each_set_bit(ch, &requests, max_channels(dev)) {
+		vc = &dev->video_channels[ch];
+
+		/*
+		 * This can either be a blue frame (with signal-lost bit set)
+		 * or a good frame (with signal-lost bit clear). If we have just
+		 * got signal, then this channel needs resetting.
+		 */
+		if (vc->no_signal && !(fifo_status & BIT(ch))) {
+			v4l2_printk(KERN_DEBUG, &dev->v4l2_dev,
+				    "video%d: signal recovered\n", vc->num);
+			vc->no_signal = false;
+			*reset_ch |= BIT(ch);
+			vc->pb = 0;
+			continue;
+		}
+		vc->no_signal = !!(fifo_status & BIT(ch));
+
+		/* Check FIFO errors only if there's signal */
+		if (!vc->no_signal) {
+			u32 fifo_ov, fifo_bad;
+
+			fifo_ov = (fifo_status >> 24) & BIT(ch);
+			fifo_bad = (fifo_status >> 16) & BIT(ch);
+			if (fifo_ov || fifo_bad) {
+				/* Mark this channel for reset */
+				v4l2_printk(KERN_DEBUG, &dev->v4l2_dev,
+					    "video%d: FIFO error\n", vc->num);
+				*reset_ch |= BIT(ch);
+				vc->pb = 0;
+				continue;
+			}
+		}
+
+		pb = !!(pb_status & BIT(ch));
+		if (vc->pb != pb) {
+			/* Mark this channel for reset */
+			v4l2_printk(KERN_DEBUG, &dev->v4l2_dev,
+				    "video%d: unexpected p-b buffer!\n",
+				    vc->num);
+			*reset_ch |= BIT(ch);
+			vc->pb = 0;
+			continue;
+		}
+
+		/* handle video stream */
+		spin_lock_irqsave(&vc->qlock, flags);
+		if (vc->curr_bufs[pb]) {
+			vb = &vc->curr_bufs[pb]->vb;
+			tw686x_buffer_copy(vc, pb, vb);
+		}
+		vc->pb = !pb;
+		tw686x_buffer_refill(vc, pb);
+		spin_unlock_irqrestore(&vc->qlock, flags);
+	}
+}
+
+void tw686x_video_free(struct tw686x_dev *dev)
+{
+	unsigned int ch, pb;
+
+	for (ch = 0; ch < max_channels(dev); ch++) {
+		struct tw686x_video_channel *vc = &dev->video_channels[ch];
+
+		if (vc->device)
+			video_unregister_device(vc->device);
+
+		for (pb = 0; pb < 2; pb++)
+			tw686x_free_dma(vc, pb);
+	}
+}
+
+int tw686x_video_init(struct tw686x_dev *dev)
+{
+	unsigned int ch, val, pb;
+	int err;
+
+	err = v4l2_device_register(&dev->pci_dev->dev, &dev->v4l2_dev);
+	if (err)
+		return err;
+
+	for (ch = 0; ch < max_channels(dev); ch++) {
+		struct tw686x_video_channel *vc = &dev->video_channels[ch];
+		struct video_device *vdev;
+
+		mutex_init(&vc->vb_mutex);
+		spin_lock_init(&vc->qlock);
+		INIT_LIST_HEAD(&vc->vidq_queued);
+
+		vc->dev = dev;
+		vc->ch = ch;
+
+		/* default settings */
+		vc->format = &formats[0];
+		vc->video_standard = V4L2_STD_NTSC;
+		vc->width = TW686X_VIDEO_WIDTH;
+		vc->height = TW686X_VIDEO_HEIGHT(vc->video_standard);
+		vc->input = 0;
+
+		reg_write(vc->dev, SDT[ch], 0);
+		tw686x_set_framerate(vc, 30);
+
+		reg_write(dev, VDELAY_LO[ch], 0x14);
+		reg_write(dev, HACTIVE_LO[ch], 0xd0);
+		reg_write(dev, VIDEO_SIZE[ch], 0);
+
+		for (pb = 0; pb < 2; pb++) {
+			err = tw686x_alloc_dma(vc, pb);
+			if (err)
+				goto error;
+		}
+
+		vc->vidq.io_modes = VB2_READ | VB2_MMAP | VB2_DMABUF;
+		vc->vidq.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+		vc->vidq.drv_priv = vc;
+		vc->vidq.buf_struct_size = sizeof(struct tw686x_v4l2_buf);
+		vc->vidq.ops = &tw686x_video_qops;
+		vc->vidq.mem_ops = &vb2_vmalloc_memops;
+		vc->vidq.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+		vc->vidq.min_buffers_needed = 2;
+		vc->vidq.lock = &vc->vb_mutex;
+
+		err = vb2_queue_init(&vc->vidq);
+		if (err) {
+			v4l2_err(&dev->v4l2_dev,
+				 "dma%d: cannot init vb2 queue\n", ch);
+			goto error;
+		}
+
+		err = v4l2_ctrl_handler_init(&vc->ctrl_handler, 4);
+		if (err) {
+			v4l2_err(&dev->v4l2_dev,
+				 "dma%d: cannot init ctrl handler\n", ch);
+			goto error;
+		}
+		v4l2_ctrl_new_std(&vc->ctrl_handler, &ctrl_ops,
+				  V4L2_CID_BRIGHTNESS, -128, 127, 1, 0);
+		v4l2_ctrl_new_std(&vc->ctrl_handler, &ctrl_ops,
+				  V4L2_CID_CONTRAST, 0, 255, 1, 100);
+		v4l2_ctrl_new_std(&vc->ctrl_handler, &ctrl_ops,
+				  V4L2_CID_SATURATION, 0, 255, 1, 128);
+		v4l2_ctrl_new_std(&vc->ctrl_handler, &ctrl_ops,
+				  V4L2_CID_HUE, -128, 127, 1, 0);
+		err = vc->ctrl_handler.error;
+		if (err)
+			goto error;
+
+		err = v4l2_ctrl_handler_setup(&vc->ctrl_handler);
+		if (err)
+			goto error;
+
+		vdev = video_device_alloc();
+		if (!vdev) {
+			v4l2_err(&dev->v4l2_dev,
+				 "dma%d: unable to allocate device\n", ch);
+			err = -ENOMEM;
+			goto error;
+		}
+
+		snprintf(vdev->name, sizeof(vdev->name), "%s video", dev->name);
+		vdev->fops = &tw686x_video_fops;
+		vdev->ioctl_ops = &tw686x_video_ioctl_ops;
+		vdev->release = video_device_release;
+		vdev->v4l2_dev = &dev->v4l2_dev;
+		vdev->queue = &vc->vidq;
+		vdev->tvnorms = V4L2_STD_525_60 | V4L2_STD_625_50;
+		vdev->minor = -1;
+		vdev->lock = &vc->vb_mutex;
+		vdev->ctrl_handler = &vc->ctrl_handler;
+		vc->device = vdev;
+		video_set_drvdata(vdev, vc);
+
+		err = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
+		if (err < 0)
+			goto error;
+		vc->num = vdev->num;
+	}
+
+	/* Set DMA frame mode on all channels. Only supported mode for now. */
+	val = TW686X_DEF_PHASE_REF;
+	for (ch = 0; ch < max_channels(dev); ch++)
+		val |= TW686X_FRAME_MODE << (16 + ch * 2);
+	reg_write(dev, PHASE_REF, val);
+
+	reg_write(dev, MISC2[0], 0xe7);
+	reg_write(dev, VCTRL1[0], 0xcc);
+	reg_write(dev, LOOP[0], 0xa5);
+	if (max_channels(dev) > 4) {
+		reg_write(dev, VCTRL1[1], 0xcc);
+		reg_write(dev, LOOP[1], 0xa5);
+		reg_write(dev, MISC2[1], 0xe7);
+	}
+	return 0;
+
+error:
+	tw686x_video_free(dev);
+	return err;
+}