text: /*
   * s3c24xx/s3c64xx SoC series Camera Interface (CAMIF) driver
   *
   * Copyright (C) 2012 Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
   * Copyright (C) 2012 Tomasz Figa <tomasz.figa@gmail.com>
   *
   * Based on drivers/media/platform/s5p-fimc,
   * Copyright (C) 2010 - 2012 Samsung Electronics Co., Ltd.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
  */
  #define pr_fmt(fmt) "%s:%d " fmt, __func__, __LINE__
  
  #include <linux/bug.h>
  #include <linux/clk.h>
  #include <linux/device.h>
  #include <linux/errno.h>
  #include <linux/i2c.h>
  #include <linux/interrupt.h>
  #include <linux/io.h>
  #include <linux/kernel.h>
  #include <linux/list.h>
  #include <linux/module.h>
  #include <linux/platform_device.h>
  #include <linux/pm_runtime.h>
  #include <linux/ratelimit.h>
  #include <linux/slab.h>
  #include <linux/types.h>
  #include <linux/videodev2.h>
  
  #include <media/media-device.h>
  #include <media/v4l2-ctrls.h>
  #include <media/v4l2-event.h>
  #include <media/v4l2-ioctl.h>
  #include <media/videobuf2-v4l2.h>
  #include <media/videobuf2-dma-contig.h>
  
  #include "camif-core.h"
  #include "camif-regs.h"
  
  static int debug;
  module_param(debug, int, 0644);
  
  /* Locking: called with vp->camif->slock spinlock held */
  static void camif_cfg_video_path(struct camif_vp *vp)
  {
  	WARN_ON(s3c_camif_get_scaler_config(vp, &vp->scaler));
  	camif_hw_set_scaler(vp);
  	camif_hw_set_flip(vp);
  	camif_hw_set_target_format(vp);
  	camif_hw_set_output_dma(vp);
  }
  
  static void camif_prepare_dma_offset(struct camif_vp *vp)
  {
  	struct camif_frame *f = &vp->out_frame;
  
  	f->dma_offset.initial = f->rect.top * f->f_width + f->rect.left;
  	f->dma_offset.line = f->f_width - (f->rect.left + f->rect.width);
  
  	pr_debug("dma_offset: initial: %d, line: %d\n",
  		 f->dma_offset.initial, f->dma_offset.line);
  }
  
  /* Locking: called with camif->slock spinlock held */
  static int s3c_camif_hw_init(struct camif_dev *camif, struct camif_vp *vp)
  {
  	const struct s3c_camif_variant *variant = camif->variant;
  
  	if (camif->sensor.sd == NULL || vp->out_fmt == NULL)
  		return -EINVAL;
  
  	if (variant->ip_revision == S3C244X_CAMIF_IP_REV)
  		camif_hw_clear_fifo_overflow(vp);
  	camif_hw_set_camera_bus(camif);
  	camif_hw_set_source_format(camif);
  	camif_hw_set_camera_crop(camif);
  	camif_hw_set_test_pattern(camif, camif->test_pattern);
  	if (variant->has_img_effect)
  		camif_hw_set_effect(camif, camif->colorfx,
  				camif->colorfx_cr, camif->colorfx_cb);
  	if (variant->ip_revision == S3C6410_CAMIF_IP_REV)
  		camif_hw_set_input_path(vp);
  	camif_cfg_video_path(vp);
  	vp->state &= ~ST_VP_CONFIG;
  
  	return 0;
  }
  
  /*
   * Initialize the video path, only up from the scaler stage. The camera
   * input interface set up is skipped. This is useful to enable one of the
   * video paths when the other is already running.
   * Locking: called with camif->slock spinlock held.
   */
  static int s3c_camif_hw_vp_init(struct camif_dev *camif, struct camif_vp *vp)
  {
  	unsigned int ip_rev = camif->variant->ip_revision;
  
  	if (vp->out_fmt == NULL)
  		return -EINVAL;
  
  	camif_prepare_dma_offset(vp);
  	if (ip_rev == S3C244X_CAMIF_IP_REV)
  		camif_hw_clear_fifo_overflow(vp);
  	camif_cfg_video_path(vp);
  	vp->state &= ~ST_VP_CONFIG;
  	return 0;
  }
  
  static int sensor_set_power(struct camif_dev *camif, int on)
  {
  	struct cam_sensor *sensor = &camif->sensor;
  	int err = 0;
  
  	if (camif->sensor.power_count == !on)
  		err = v4l2_subdev_call(sensor->sd, core, s_power, on);
  	if (!err)
  		sensor->power_count += on ? 1 : -1;
  
  	pr_debug("on: %d, power_count: %d, err: %d\n",
  		 on, sensor->power_count, err);
  
  	return err;
  }
  
  static int sensor_set_streaming(struct camif_dev *camif, int on)
  {
  	struct cam_sensor *sensor = &camif->sensor;
  	int err = 0;
  
  	if (camif->sensor.stream_count == !on)
  		err = v4l2_subdev_call(sensor->sd, video, s_stream, on);
  	if (!err)
  		sensor->stream_count += on ? 1 : -1;
  
  	pr_debug("on: %d, stream_count: %d, err: %d\n",
  		 on, sensor->stream_count, err);
  
  	return err;
  }
  
  /*
   * Reinitialize the driver so it is ready to start streaming again.
   * Return any buffers to vb2, perform CAMIF software reset and
   * turn off streaming at the data pipeline (sensor) if required.
   */
  static int camif_reinitialize(struct camif_vp *vp)
  {
  	struct camif_dev *camif = vp->camif;
  	struct camif_buffer *buf;
  	unsigned long flags;
  	bool streaming;
  
  	spin_lock_irqsave(&camif->slock, flags);
  	streaming = vp->state & ST_VP_SENSOR_STREAMING;
  
  	vp->state &= ~(ST_VP_PENDING | ST_VP_RUNNING | ST_VP_OFF |
  		       ST_VP_ABORTING | ST_VP_STREAMING |
  		       ST_VP_SENSOR_STREAMING | ST_VP_LASTIRQ);
  
  	/* Release unused buffers */
  	while (!list_empty(&vp->pending_buf_q)) {
  		buf = camif_pending_queue_pop(vp);
  		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
  	}
  
  	while (!list_empty(&vp->active_buf_q)) {
  		buf = camif_active_queue_pop(vp);
  		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
  	}
  
  	spin_unlock_irqrestore(&camif->slock, flags);
  
  	if (!streaming)
  		return 0;
  
  	return sensor_set_streaming(camif, 0);
  }
  
  static bool s3c_vp_active(struct camif_vp *vp)
  {
  	struct camif_dev *camif = vp->camif;
  	unsigned long flags;
  	bool ret;
  
  	spin_lock_irqsave(&camif->slock, flags);
  	ret = (vp->state & ST_VP_RUNNING) || (vp->state & ST_VP_PENDING);
  	spin_unlock_irqrestore(&camif->slock, flags);
  
  	return ret;
  }
  
  static bool camif_is_streaming(struct camif_dev *camif)
  {
  	unsigned long flags;
  	bool status;
  
  	spin_lock_irqsave(&camif->slock, flags);
  	status = camif->stream_count > 0;
  	spin_unlock_irqrestore(&camif->slock, flags);
  
  	return status;
  }
  
  static int camif_stop_capture(struct camif_vp *vp)
  {
  	struct camif_dev *camif = vp->camif;
  	unsigned long flags;
  	int ret;
  
  	if (!s3c_vp_active(vp))
  		return 0;
  
  	spin_lock_irqsave(&camif->slock, flags);
  	vp->state &= ~(ST_VP_OFF | ST_VP_LASTIRQ);
  	vp->state |= ST_VP_ABORTING;
  	spin_unlock_irqrestore(&camif->slock, flags);
  
  	ret = wait_event_timeout(vp->irq_queue,
  			   !(vp->state & ST_VP_ABORTING),
  			   msecs_to_jiffies(CAMIF_STOP_TIMEOUT));
  
  	spin_lock_irqsave(&camif->slock, flags);
  
  	if (ret == 0 && !(vp->state & ST_VP_OFF)) {
  		/* Timed out, forcibly stop capture */
  		vp->state &= ~(ST_VP_OFF | ST_VP_ABORTING |
  			       ST_VP_LASTIRQ);
  
  		camif_hw_disable_capture(vp);
  		camif_hw_enable_scaler(vp, false);
  	}
  
  	spin_unlock_irqrestore(&camif->slock, flags);
  
  	return camif_reinitialize(vp);
  }
  
  static int camif_prepare_addr(struct camif_vp *vp, struct vb2_buffer *vb,
  			      struct camif_addr *paddr)
  {
  	struct camif_frame *frame = &vp->out_frame;
  	u32 pix_size;
  
  	if (vb == NULL || frame == NULL)
  		return -EINVAL;
  
  	pix_size = frame->rect.width * frame->rect.height;
  
  	pr_debug("colplanes: %d, pix_size: %u\n",
  		 vp->out_fmt->colplanes, pix_size);
  
  	paddr->y = vb2_dma_contig_plane_dma_addr(vb, 0);
  
  	switch (vp->out_fmt->colplanes) {
  	case 1:
  		paddr->cb = 0;
  		paddr->cr = 0;
  		break;
  	case 2:
  		/* decompose Y into Y/Cb */
  		paddr->cb = (u32)(paddr->y + pix_size);
  		paddr->cr = 0;
  		break;
  	case 3:
  		paddr->cb = (u32)(paddr->y + pix_size);
  		/* decompose Y into Y/Cb/Cr */
  		if (vp->out_fmt->color == IMG_FMT_YCBCR422P)
  			paddr->cr = (u32)(paddr->cb + (pix_size >> 1));
  		else /* 420 */
  			paddr->cr = (u32)(paddr->cb + (pix_size >> 2));
  
  		if (vp->out_fmt->color == IMG_FMT_YCRCB420)
  			swap(paddr->cb, paddr->cr);
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	pr_debug("DMA address: y: %pad  cb: %pad cr: %pad\n",
  		 &paddr->y, &paddr->cb, &paddr->cr);
  
  	return 0;
  }
  
  irqreturn_t s3c_camif_irq_handler(int irq, void *priv)
  {
  	struct camif_vp *vp = priv;
  	struct camif_dev *camif = vp->camif;
  	unsigned int ip_rev = camif->variant->ip_revision;
  	unsigned int status;
  
  	spin_lock(&camif->slock);
  
  	if (ip_rev == S3C6410_CAMIF_IP_REV)
  		camif_hw_clear_pending_irq(vp);
  
  	status = camif_hw_get_status(vp);
  
  	if (ip_rev == S3C244X_CAMIF_IP_REV && (status & CISTATUS_OVF_MASK)) {
  		camif_hw_clear_fifo_overflow(vp);
  		goto unlock;
  	}
  
  	if (vp->state & ST_VP_ABORTING) {
  		if (vp->state & ST_VP_OFF) {
  			/* Last IRQ */
  			vp->state &= ~(ST_VP_OFF | ST_VP_ABORTING |
  				       ST_VP_LASTIRQ);
  			wake_up(&vp->irq_queue);
  			goto unlock;
  		} else if (vp->state & ST_VP_LASTIRQ) {
  			camif_hw_disable_capture(vp);
  			camif_hw_enable_scaler(vp, false);
  			camif_hw_set_lastirq(vp, false);
  			vp->state |= ST_VP_OFF;
  		} else {
  			/* Disable capture, enable last IRQ */
  			camif_hw_set_lastirq(vp, true);
  			vp->state |= ST_VP_LASTIRQ;
  		}
  	}
  
  	if (!list_empty(&vp->pending_buf_q) && (vp->state & ST_VP_RUNNING) &&
  	    !list_empty(&vp->active_buf_q)) {
  		unsigned int index;
  		struct camif_buffer *vbuf;
  		/*
  		 * Get previous DMA write buffer index:
  		 * 0 => DMA buffer 0, 2;
  		 * 1 => DMA buffer 1, 3.
  		 */
  		index = (CISTATUS_FRAMECNT(status) + 2) & 1;
  		vbuf = camif_active_queue_peek(vp, index);
  
  		if (!WARN_ON(vbuf == NULL)) {
  			/* Dequeue a filled buffer */
  			vbuf->vb.vb2_buf.timestamp = ktime_get_ns();
  			vbuf->vb.sequence = vp->frame_sequence++;
  			vb2_buffer_done(&vbuf->vb.vb2_buf, VB2_BUF_STATE_DONE);
  
  			/* Set up an empty buffer at the DMA engine */
  			vbuf = camif_pending_queue_pop(vp);
  			vbuf->index = index;
  			camif_hw_set_output_addr(vp, &vbuf->paddr, index);
  			camif_hw_set_output_addr(vp, &vbuf->paddr, index + 2);
  
  			/* Scheduled in H/W, add to the queue */
  			camif_active_queue_add(vp, vbuf);
  		}
  	} else if (!(vp->state & ST_VP_ABORTING) &&
  		   (vp->state & ST_VP_PENDING))  {
  		vp->state |= ST_VP_RUNNING;
  	}
  
  	if (vp->state & ST_VP_CONFIG) {
  		camif_prepare_dma_offset(vp);
  		camif_hw_set_camera_crop(camif);
  		camif_hw_set_scaler(vp);
  		camif_hw_set_flip(vp);
  		camif_hw_set_test_pattern(camif, camif->test_pattern);
  		if (camif->variant->has_img_effect)
  			camif_hw_set_effect(camif, camif->colorfx,
  				    camif->colorfx_cr, camif->colorfx_cb);
  		vp->state &= ~ST_VP_CONFIG;
  	}
  unlock:
  	spin_unlock(&camif->slock);
  	return IRQ_HANDLED;
  }
  
  static int start_streaming(struct vb2_queue *vq, unsigned int count)
  {
  	struct camif_vp *vp = vb2_get_drv_priv(vq);
  	struct camif_dev *camif = vp->camif;
  	unsigned long flags;
  	int ret;
  
  	/*
  	 * We assume the codec capture path is always activated
  	 * first, before the preview path starts streaming.
  	 * This is required to avoid internal FIFO overflow and
  	 * a need for CAMIF software reset.
  	 */
  	spin_lock_irqsave(&camif->slock, flags);
  
  	if (camif->stream_count == 0) {
  		camif_hw_reset(camif);
  		ret = s3c_camif_hw_init(camif, vp);
  	} else {
  		ret = s3c_camif_hw_vp_init(camif, vp);
  	}
  	spin_unlock_irqrestore(&camif->slock, flags);
  
  	if (ret < 0) {
  		camif_reinitialize(vp);
  		return ret;
  	}
  
  	spin_lock_irqsave(&camif->slock, flags);
  	vp->frame_sequence = 0;
  	vp->state |= ST_VP_PENDING;
  
  	if (!list_empty(&vp->pending_buf_q) &&
  	    (!(vp->state & ST_VP_STREAMING) ||
  	     !(vp->state & ST_VP_SENSOR_STREAMING))) {
  
  		camif_hw_enable_scaler(vp, vp->scaler.enable);
  		camif_hw_enable_capture(vp);
  		vp->state |= ST_VP_STREAMING;
  
  		if (!(vp->state & ST_VP_SENSOR_STREAMING)) {
  			vp->state |= ST_VP_SENSOR_STREAMING;
  			spin_unlock_irqrestore(&camif->slock, flags);
  			ret = sensor_set_streaming(camif, 1);
  			if (ret)
  				v4l2_err(&vp->vdev, "Sensor s_stream failed\n");
  			if (debug)
  				camif_hw_dump_regs(camif, __func__);
  
  			return ret;
  		}
  	}
  
  	spin_unlock_irqrestore(&camif->slock, flags);
  	return 0;
  }
  
  static void stop_streaming(struct vb2_queue *vq)
  {
  	struct camif_vp *vp = vb2_get_drv_priv(vq);
  	camif_stop_capture(vp);
  }
  
  static int queue_setup(struct vb2_queue *vq,
  		       unsigned int *num_buffers, unsigned int *num_planes,
  		       unsigned int sizes[], struct device *alloc_devs[])
  {
  	struct camif_vp *vp = vb2_get_drv_priv(vq);
  	struct camif_frame *frame = &vp->out_frame;
  	const struct camif_fmt *fmt = vp->out_fmt;
  	unsigned int size;
  
  	if (fmt == NULL)
  		return -EINVAL;
  
  	size = (frame->f_width * frame->f_height * fmt->depth) / 8;
  
  	if (*num_planes)
  		return sizes[0] < size ? -EINVAL : 0;
  
  	*num_planes = 1;
  	sizes[0] = size;
  
  	pr_debug("size: %u\n", sizes[0]);
  	return 0;
  }
  
  static int buffer_prepare(struct vb2_buffer *vb)
  {
  	struct camif_vp *vp = vb2_get_drv_priv(vb->vb2_queue);
  
  	if (vp->out_fmt == NULL)
  		return -EINVAL;
  
  	if (vb2_plane_size(vb, 0) < vp->payload) {
  		v4l2_err(&vp->vdev, "buffer too small: %lu, required: %u\n",
  			 vb2_plane_size(vb, 0), vp->payload);
  		return -EINVAL;
  	}
  	vb2_set_plane_payload(vb, 0, vp->payload);
  
  	return 0;
  }
  
  static void buffer_queue(struct vb2_buffer *vb)
  {
  	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  	struct camif_buffer *buf = container_of(vbuf, struct camif_buffer, vb);
  	struct camif_vp *vp = vb2_get_drv_priv(vb->vb2_queue);
  	struct camif_dev *camif = vp->camif;
  	unsigned long flags;
  
  	spin_lock_irqsave(&camif->slock, flags);
  	WARN_ON(camif_prepare_addr(vp, &buf->vb.vb2_buf, &buf->paddr));
  
  	if (!(vp->state & ST_VP_STREAMING) && vp->active_buffers < 2) {
  		/* Schedule an empty buffer in H/W */
  		buf->index = vp->buf_index;
  
  		camif_hw_set_output_addr(vp, &buf->paddr, buf->index);
  		camif_hw_set_output_addr(vp, &buf->paddr, buf->index + 2);
  
  		camif_active_queue_add(vp, buf);
  		vp->buf_index = !vp->buf_index;
  	} else {
  		camif_pending_queue_add(vp, buf);
  	}
  
  	if (vb2_is_streaming(&vp->vb_queue) && !list_empty(&vp->pending_buf_q)
  		&& !(vp->state & ST_VP_STREAMING)) {
  
  		vp->state |= ST_VP_STREAMING;
  		camif_hw_enable_scaler(vp, vp->scaler.enable);
  		camif_hw_enable_capture(vp);
  		spin_unlock_irqrestore(&camif->slock, flags);
  
  		if (!(vp->state & ST_VP_SENSOR_STREAMING)) {
  			if (sensor_set_streaming(camif, 1) == 0)
  				vp->state |= ST_VP_SENSOR_STREAMING;
  			else
  				v4l2_err(&vp->vdev, "Sensor s_stream failed\n");
  
  			if (debug)
  				camif_hw_dump_regs(camif, __func__);
  		}
  		return;
  	}
  	spin_unlock_irqrestore(&camif->slock, flags);
  }
  
  static const struct vb2_ops s3c_camif_qops = {
  	.queue_setup	 = queue_setup,
  	.buf_prepare	 = buffer_prepare,
  	.buf_queue	 = buffer_queue,
  	.wait_prepare	 = vb2_ops_wait_prepare,
  	.wait_finish	 = vb2_ops_wait_finish,
  	.start_streaming = start_streaming,
  	.stop_streaming	 = stop_streaming,
  };
  
  static int s3c_camif_open(struct file *file)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	struct camif_dev *camif = vp->camif;
  	int ret;
  
  	pr_debug("[vp%d] state: %#x,  owner: %p, pid: %d\n", vp->id,
  		 vp->state, vp->owner, task_pid_nr(current));
  
  	if (mutex_lock_interruptible(&camif->lock))
  		return -ERESTARTSYS;
  
  	ret = v4l2_fh_open(file);
  	if (ret < 0)
  		goto unlock;
  
  	ret = pm_runtime_get_sync(camif->dev);
  	if (ret < 0)
  		goto err_pm;
  
  	ret = sensor_set_power(camif, 1);
  	if (!ret)
  		goto unlock;
  
  	pm_runtime_put(camif->dev);
  err_pm:
  	v4l2_fh_release(file);
  unlock:
  	mutex_unlock(&camif->lock);
  	return ret;
  }
  
  static int s3c_camif_close(struct file *file)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	struct camif_dev *camif = vp->camif;
  	int ret;
  
  	pr_debug("[vp%d] state: %#x, owner: %p, pid: %d\n", vp->id,
  		 vp->state, vp->owner, task_pid_nr(current));
  
  	mutex_lock(&camif->lock);
  
  	if (vp->owner == file->private_data) {
  		camif_stop_capture(vp);
  		vb2_queue_release(&vp->vb_queue);
  		vp->owner = NULL;
  	}
  
  	sensor_set_power(camif, 0);
  
  	pm_runtime_put(camif->dev);
  	ret = v4l2_fh_release(file);
  
  	mutex_unlock(&camif->lock);
  	return ret;
  }
  
  static unsigned int s3c_camif_poll(struct file *file,
  				   struct poll_table_struct *wait)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	struct camif_dev *camif = vp->camif;
  	int ret;
  
  	mutex_lock(&camif->lock);
  	if (vp->owner && vp->owner != file->private_data)
  		ret = -EBUSY;
  	else
  		ret = vb2_poll(&vp->vb_queue, file, wait);
  
  	mutex_unlock(&camif->lock);
  	return ret;
  }
  
  static int s3c_camif_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	int ret;
  
  	if (vp->owner && vp->owner != file->private_data)
  		ret = -EBUSY;
  	else
  		ret = vb2_mmap(&vp->vb_queue, vma);
  
  	return ret;
  }
  
  static const struct v4l2_file_operations s3c_camif_fops = {
  	.owner		= THIS_MODULE,
  	.open		= s3c_camif_open,
  	.release	= s3c_camif_close,
  	.poll		= s3c_camif_poll,
  	.unlocked_ioctl	= video_ioctl2,
  	.mmap		= s3c_camif_mmap,
  };
  
  /*
   * Video node IOCTLs
   */
  
  static int s3c_camif_vidioc_querycap(struct file *file, void *priv,
  				     struct v4l2_capability *cap)
  {
  	struct camif_vp *vp = video_drvdata(file);
  
  	strlcpy(cap->driver, S3C_CAMIF_DRIVER_NAME, sizeof(cap->driver));
  	strlcpy(cap->card, S3C_CAMIF_DRIVER_NAME, sizeof(cap->card));
  	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s.%d",
  		 dev_name(vp->camif->dev), vp->id);
  
  	cap->device_caps = V4L2_CAP_STREAMING | V4L2_CAP_VIDEO_CAPTURE;
  	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
  
  	return 0;
  }
  
  static int s3c_camif_vidioc_enum_input(struct file *file, void *priv,
  				       struct v4l2_input *input)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	struct v4l2_subdev *sensor = vp->camif->sensor.sd;
  
  	if (input->index || sensor == NULL)
  		return -EINVAL;
  
  	input->type = V4L2_INPUT_TYPE_CAMERA;
  	strlcpy(input->name, sensor->name, sizeof(input->name));
  	return 0;
  }
  
  static int s3c_camif_vidioc_s_input(struct file *file, void *priv,
  				    unsigned int i)
  {
  	return i == 0 ? 0 : -EINVAL;
  }
  
  static int s3c_camif_vidioc_g_input(struct file *file, void *priv,
  				    unsigned int *i)
  {
  	*i = 0;
  	return 0;
  }
  
  static int s3c_camif_vidioc_enum_fmt(struct file *file, void *priv,
  				     struct v4l2_fmtdesc *f)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	const struct camif_fmt *fmt;
  
  	fmt = s3c_camif_find_format(vp, NULL, f->index);
  	if (!fmt)
  		return -EINVAL;
  
  	strlcpy(f->description, fmt->name, sizeof(f->description));
  	f->pixelformat = fmt->fourcc;
  
  	pr_debug("fmt(%d): %s\n", f->index, f->description);
  	return 0;
  }
  
  static int s3c_camif_vidioc_g_fmt(struct file *file, void *priv,
  				  struct v4l2_format *f)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	struct v4l2_pix_format *pix = &f->fmt.pix;
  	struct camif_frame *frame = &vp->out_frame;
  	const struct camif_fmt *fmt = vp->out_fmt;
  
  	pix->bytesperline = frame->f_width * fmt->ybpp;
  	pix->sizeimage = vp->payload;
  
  	pix->pixelformat = fmt->fourcc;
  	pix->width = frame->f_width;
  	pix->height = frame->f_height;
  	pix->field = V4L2_FIELD_NONE;
  	pix->colorspace = V4L2_COLORSPACE_JPEG;
  
  	return 0;
  }
  
  static int __camif_video_try_format(struct camif_vp *vp,
  				    struct v4l2_pix_format *pix,
  				    const struct camif_fmt **ffmt)
  {
  	struct camif_dev *camif = vp->camif;
  	struct v4l2_rect *crop = &camif->camif_crop;
  	unsigned int wmin, hmin, sc_hrmax, sc_vrmax;
  	const struct vp_pix_limits *pix_lim;
  	const struct camif_fmt *fmt;
  
  	fmt = s3c_camif_find_format(vp, &pix->pixelformat, 0);
  
  	if (WARN_ON(fmt == NULL))
  		return -EINVAL;
  
  	if (ffmt)
  		*ffmt = fmt;
  
  	pix_lim = &camif->variant->vp_pix_limits[vp->id];
  
  	pr_debug("fmt: %ux%u, crop: %ux%u, bytesperline: %u\n",
  		 pix->width, pix->height, crop->width, crop->height,
  		 pix->bytesperline);
  	/*
  	 * Calculate minimum width and height according to the configured
  	 * camera input interface crop rectangle and the resizer's capabilities.
  	 */
  	sc_hrmax = min(SCALER_MAX_RATIO, 1 << (ffs(crop->width) - 3));
  	sc_vrmax = min(SCALER_MAX_RATIO, 1 << (ffs(crop->height) - 1));
  
  	wmin = max_t(u32, pix_lim->min_out_width, crop->width / sc_hrmax);
  	wmin = round_up(wmin, pix_lim->out_width_align);
  	hmin = max_t(u32, 8, crop->height / sc_vrmax);
  	hmin = round_up(hmin, 8);
  
  	v4l_bound_align_image(&pix->width, wmin, pix_lim->max_sc_out_width,
  			      ffs(pix_lim->out_width_align) - 1,
  			      &pix->height, hmin, pix_lim->max_height, 0, 0);
  
  	pix->bytesperline = pix->width * fmt->ybpp;
  	pix->sizeimage = (pix->width * pix->height * fmt->depth) / 8;
  	pix->pixelformat = fmt->fourcc;
  	pix->colorspace = V4L2_COLORSPACE_JPEG;
  	pix->field = V4L2_FIELD_NONE;
  
  	pr_debug("%ux%u, wmin: %d, hmin: %d, sc_hrmax: %d, sc_vrmax: %d\n",
  		 pix->width, pix->height, wmin, hmin, sc_hrmax, sc_vrmax);
  
  	return 0;
  }
  
  static int s3c_camif_vidioc_try_fmt(struct file *file, void *priv,
  				    struct v4l2_format *f)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	return __camif_video_try_format(vp, &f->fmt.pix, NULL);
  }
  
  static int s3c_camif_vidioc_s_fmt(struct file *file, void *priv,
  				  struct v4l2_format *f)
  {
  	struct v4l2_pix_format *pix = &f->fmt.pix;
  	struct camif_vp *vp = video_drvdata(file);
  	struct camif_frame *out_frame = &vp->out_frame;
  	const struct camif_fmt *fmt = NULL;
  	int ret;
  
  	pr_debug("[vp%d]\n", vp->id);
  
  	if (vb2_is_busy(&vp->vb_queue))
  		return -EBUSY;
  
  	ret = __camif_video_try_format(vp, &f->fmt.pix, &fmt);
  	if (ret < 0)
  		return ret;
  
  	vp->out_fmt = fmt;
  	vp->payload = pix->sizeimage;
  	out_frame->f_width = pix->width;
  	out_frame->f_height = pix->height;
  
  	/* Reset composition rectangle */
  	out_frame->rect.width = pix->width;
  	out_frame->rect.height = pix->height;
  	out_frame->rect.left = 0;
  	out_frame->rect.top = 0;
  
  	if (vp->owner == NULL)
  		vp->owner = priv;
  
  	pr_debug("%ux%u. payload: %u. fmt: %s. %d %d. sizeimage: %d. bpl: %d\n",
  		out_frame->f_width, out_frame->f_height, vp->payload, fmt->name,
  		pix->width * pix->height * fmt->depth, fmt->depth,
  		pix->sizeimage, pix->bytesperline);
  
  	return 0;
  }
  
  /* Only check pixel formats at the sensor and the camif subdev pads */
  static int camif_pipeline_validate(struct camif_dev *camif)
  {
  	struct v4l2_subdev_format src_fmt;
  	struct media_pad *pad;
  	int ret;
  
  	/* Retrieve format at the sensor subdev source pad */
  	pad = media_entity_remote_pad(&camif->pads[0]);
  	if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
  		return -EPIPE;
  
  	src_fmt.pad = pad->index;
  	src_fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
  	ret = v4l2_subdev_call(camif->sensor.sd, pad, get_fmt, NULL, &src_fmt);
  	if (ret < 0 && ret != -ENOIOCTLCMD)
  		return -EPIPE;
  
  	if (src_fmt.format.width != camif->mbus_fmt.width ||
  	    src_fmt.format.height != camif->mbus_fmt.height ||
  	    src_fmt.format.code != camif->mbus_fmt.code)
  		return -EPIPE;
  
  	return 0;
  }
  
  static int s3c_camif_streamon(struct file *file, void *priv,
  			      enum v4l2_buf_type type)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	struct camif_dev *camif = vp->camif;
  	struct media_entity *sensor = &camif->sensor.sd->entity;
  	int ret;
  
  	pr_debug("[vp%d]\n", vp->id);
  
  	if (type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
  		return -EINVAL;
  
  	if (vp->owner && vp->owner != priv)
  		return -EBUSY;
  
  	if (s3c_vp_active(vp))
  		return 0;
  
  	ret = media_pipeline_start(sensor, camif->m_pipeline);
  	if (ret < 0)
  		return ret;
  
  	ret = camif_pipeline_validate(camif);
  	if (ret < 0) {
  		media_pipeline_stop(sensor);
  		return ret;
  	}
  
  	return vb2_streamon(&vp->vb_queue, type);
  }
  
  static int s3c_camif_streamoff(struct file *file, void *priv,
  			       enum v4l2_buf_type type)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	struct camif_dev *camif = vp->camif;
  	int ret;
  
  	pr_debug("[vp%d]\n", vp->id);
  
  	if (type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
  		return -EINVAL;
  
  	if (vp->owner && vp->owner != priv)
  		return -EBUSY;
  
  	ret = vb2_streamoff(&vp->vb_queue, type);
  	if (ret == 0)
  		media_pipeline_stop(&camif->sensor.sd->entity);
  	return ret;
  }
  
  static int s3c_camif_reqbufs(struct file *file, void *priv,
  			     struct v4l2_requestbuffers *rb)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	int ret;
  
  	pr_debug("[vp%d] rb count: %d, owner: %p, priv: %p\n",
  		 vp->id, rb->count, vp->owner, priv);
  
  	if (vp->owner && vp->owner != priv)
  		return -EBUSY;
  
  	if (rb->count)
  		rb->count = max_t(u32, CAMIF_REQ_BUFS_MIN, rb->count);
  	else
  		vp->owner = NULL;
  
  	ret = vb2_reqbufs(&vp->vb_queue, rb);
  	if (ret < 0)
  		return ret;
  
  	if (rb->count && rb->count < CAMIF_REQ_BUFS_MIN) {
  		rb->count = 0;
  		vb2_reqbufs(&vp->vb_queue, rb);
  		ret = -ENOMEM;
  	}
  
  	vp->reqbufs_count = rb->count;
  	if (vp->owner == NULL && rb->count > 0)
  		vp->owner = priv;
  
  	return ret;
  }
  
  static int s3c_camif_querybuf(struct file *file, void *priv,
  			      struct v4l2_buffer *buf)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	return vb2_querybuf(&vp->vb_queue, buf);
  }
  
  static int s3c_camif_qbuf(struct file *file, void *priv,
  			  struct v4l2_buffer *buf)
  {
  	struct camif_vp *vp = video_drvdata(file);
  
  	pr_debug("[vp%d]\n", vp->id);
  
  	if (vp->owner && vp->owner != priv)
  		return -EBUSY;
  
  	return vb2_qbuf(&vp->vb_queue, buf);
  }
  
  static int s3c_camif_dqbuf(struct file *file, void *priv,
  			   struct v4l2_buffer *buf)
  {
  	struct camif_vp *vp = video_drvdata(file);
  
  	pr_debug("[vp%d] sequence: %d\n", vp->id, vp->frame_sequence);
  
  	if (vp->owner && vp->owner != priv)
  		return -EBUSY;
  
  	return vb2_dqbuf(&vp->vb_queue, buf, file->f_flags & O_NONBLOCK);
  }
  
  static int s3c_camif_create_bufs(struct file *file, void *priv,
  				 struct v4l2_create_buffers *create)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	int ret;
  
  	if (vp->owner && vp->owner != priv)
  		return -EBUSY;
  
  	create->count = max_t(u32, 1, create->count);
  	ret = vb2_create_bufs(&vp->vb_queue, create);
  
  	if (!ret && vp->owner == NULL)
  		vp->owner = priv;
  
  	return ret;
  }
  
  static int s3c_camif_prepare_buf(struct file *file, void *priv,
  				 struct v4l2_buffer *b)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	return vb2_prepare_buf(&vp->vb_queue, b);
  }
  
  static int s3c_camif_g_selection(struct file *file, void *priv,
  				 struct v4l2_selection *sel)
  {
  	struct camif_vp *vp = video_drvdata(file);
  
  	if (sel->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
  		return -EINVAL;
  
  	switch (sel->target) {
  	case V4L2_SEL_TGT_COMPOSE_BOUNDS:
  	case V4L2_SEL_TGT_COMPOSE_DEFAULT:
  		sel->r.left = 0;
  		sel->r.top = 0;
  		sel->r.width = vp->out_frame.f_width;
  		sel->r.height = vp->out_frame.f_height;
  		return 0;
  
  	case V4L2_SEL_TGT_COMPOSE:
  		sel->r = vp->out_frame.rect;
  		return 0;
  	}
  
  	return -EINVAL;
  }
  
  static void __camif_try_compose(struct camif_dev *camif, struct camif_vp *vp,
  				struct v4l2_rect *r)
  {
  	/* s3c244x doesn't support composition */
  	if (camif->variant->ip_revision == S3C244X_CAMIF_IP_REV) {
  		*r = vp->out_frame.rect;
  		return;
  	}
  
  	/* TODO: s3c64xx */
  }
  
  static int s3c_camif_s_selection(struct file *file, void *priv,
  				 struct v4l2_selection *sel)
  {
  	struct camif_vp *vp = video_drvdata(file);
  	struct camif_dev *camif = vp->camif;
  	struct v4l2_rect rect = sel->r;
  	unsigned long flags;
  
  	if (sel->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
  	    sel->target != V4L2_SEL_TGT_COMPOSE)
  		return -EINVAL;
  
  	__camif_try_compose(camif, vp, &rect);
  
  	sel->r = rect;
  	spin_lock_irqsave(&camif->slock, flags);
  	vp->out_frame.rect = rect;
  	vp->state |= ST_VP_CONFIG;
  	spin_unlock_irqrestore(&camif->slock, flags);
  
  	pr_debug("type: %#x, target: %#x, flags: %#x, (%d,%d)/%dx%d\n",
  		sel->type, sel->target, sel->flags,
  		sel->r.left, sel->r.top, sel->r.width, sel->r.height);
  
  	return 0;
  }
  
  static const struct v4l2_ioctl_ops s3c_camif_ioctl_ops = {
  	.vidioc_querycap	  = s3c_camif_vidioc_querycap,
  	.vidioc_enum_input	  = s3c_camif_vidioc_enum_input,
  	.vidioc_g_input		  = s3c_camif_vidioc_g_input,
  	.vidioc_s_input		  = s3c_camif_vidioc_s_input,
  	.vidioc_enum_fmt_vid_cap  = s3c_camif_vidioc_enum_fmt,
  	.vidioc_try_fmt_vid_cap	  = s3c_camif_vidioc_try_fmt,
  	.vidioc_s_fmt_vid_cap	  = s3c_camif_vidioc_s_fmt,
  	.vidioc_g_fmt_vid_cap	  = s3c_camif_vidioc_g_fmt,
  	.vidioc_g_selection	  = s3c_camif_g_selection,
  	.vidioc_s_selection	  = s3c_camif_s_selection,
  	.vidioc_reqbufs		  = s3c_camif_reqbufs,
  	.vidioc_querybuf	  = s3c_camif_querybuf,
  	.vidioc_prepare_buf	  = s3c_camif_prepare_buf,
  	.vidioc_create_bufs	  = s3c_camif_create_bufs,
  	.vidioc_qbuf		  = s3c_camif_qbuf,
  	.vidioc_dqbuf		  = s3c_camif_dqbuf,
  	.vidioc_streamon	  = s3c_camif_streamon,
  	.vidioc_streamoff	  = s3c_camif_streamoff,
  	.vidioc_subscribe_event	  = v4l2_ctrl_subscribe_event,
  	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
  	.vidioc_log_status	  = v4l2_ctrl_log_status,
  };
  
  /*
   * Video node controls
   */
  static int s3c_camif_video_s_ctrl(struct v4l2_ctrl *ctrl)
  {
  	struct camif_vp *vp = ctrl->priv;
  	struct camif_dev *camif = vp->camif;
  	unsigned long flags;
  
  	pr_debug("[vp%d] ctrl: %s, value: %d\n", vp->id,
  		 ctrl->name, ctrl->val);
  
  	spin_lock_irqsave(&camif->slock, flags);
  
  	switch (ctrl->id) {
  	case V4L2_CID_HFLIP:
  		vp->hflip = ctrl->val;
  		break;
  
  	case V4L2_CID_VFLIP:
  		vp->vflip = ctrl->val;
  		break;
  	}
  
  	vp->state |= ST_VP_CONFIG;
  	spin_unlock_irqrestore(&camif->slock, flags);
  	return 0;
  }
  
  /* Codec and preview video node control ops */
  static const struct v4l2_ctrl_ops s3c_camif_video_ctrl_ops = {
  	.s_ctrl = s3c_camif_video_s_ctrl,
  };
  
  int s3c_camif_register_video_node(struct camif_dev *camif, int idx)
  {
  	struct camif_vp *vp = &camif->vp[idx];
  	struct vb2_queue *q = &vp->vb_queue;
  	struct video_device *vfd = &vp->vdev;
  	struct v4l2_ctrl *ctrl;
  	int ret;
  
  	memset(vfd, 0, sizeof(*vfd));
  	snprintf(vfd->name, sizeof(vfd->name), "camif-%s",
  		 vp->id == 0 ? "codec" : "preview");
  
  	vfd->fops = &s3c_camif_fops;
  	vfd->ioctl_ops = &s3c_camif_ioctl_ops;
  	vfd->v4l2_dev = &camif->v4l2_dev;
  	vfd->minor = -1;
  	vfd->release = video_device_release_empty;
  	vfd->lock = &camif->lock;
  	vp->reqbufs_count = 0;
  
  	INIT_LIST_HEAD(&vp->pending_buf_q);
  	INIT_LIST_HEAD(&vp->active_buf_q);
  
  	memset(q, 0, sizeof(*q));
  	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
  	q->io_modes = VB2_MMAP | VB2_USERPTR;
  	q->ops = &s3c_camif_qops;
  	q->mem_ops = &vb2_dma_contig_memops;
  	q->buf_struct_size = sizeof(struct camif_buffer);
  	q->drv_priv = vp;
  	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
  	q->lock = &vp->camif->lock;
  	q->dev = camif->v4l2_dev.dev;
  
  	ret = vb2_queue_init(q);
  	if (ret)
  		goto err_vd_rel;
  
  	vp->pad.flags = MEDIA_PAD_FL_SINK;
  	ret = media_entity_pads_init(&vfd->entity, 1, &vp->pad);
  	if (ret)
  		goto err_vd_rel;
  
  	video_set_drvdata(vfd, vp);
  
  	v4l2_ctrl_handler_init(&vp->ctrl_handler, 1);
  	ctrl = v4l2_ctrl_new_std(&vp->ctrl_handler, &s3c_camif_video_ctrl_ops,
  				 V4L2_CID_HFLIP, 0, 1, 1, 0);
  	if (ctrl)
  		ctrl->priv = vp;
  	ctrl = v4l2_ctrl_new_std(&vp->ctrl_handler, &s3c_camif_video_ctrl_ops,
  				 V4L2_CID_VFLIP, 0, 1, 1, 0);
  	if (ctrl)
  		ctrl->priv = vp;
  
  	ret = vp->ctrl_handler.error;
  	if (ret < 0)
  		goto err_me_cleanup;
  
  	vfd->ctrl_handler = &vp->ctrl_handler;
  
  	ret = video_register_device(vfd, VFL_TYPE_GRABBER, -1);
  	if (ret)
  		goto err_ctrlh_free;
  
  	v4l2_info(&camif->v4l2_dev, "registered %s as /dev/%s\n",
  		  vfd->name, video_device_node_name(vfd));
  	return 0;
  
  err_ctrlh_free:
  	v4l2_ctrl_handler_free(&vp->ctrl_handler);
  err_me_cleanup:
  	media_entity_cleanup(&vfd->entity);
  err_vd_rel:
  	video_device_release(vfd);
  	return ret;
  }
  
  void s3c_camif_unregister_video_node(struct camif_dev *camif, int idx)
  {
  	struct video_device *vfd = &camif->vp[idx].vdev;
  
  	if (video_is_registered(vfd)) {
  		video_unregister_device(vfd);
  		media_entity_cleanup(&vfd->entity);
  		v4l2_ctrl_handler_free(vfd->ctrl_handler);
  	}
  }
  
  /* Media bus pixel formats supported at the camif input */
  static const u32 camif_mbus_formats[] = {
  	MEDIA_BUS_FMT_YUYV8_2X8,
  	MEDIA_BUS_FMT_YVYU8_2X8,
  	MEDIA_BUS_FMT_UYVY8_2X8,
  	MEDIA_BUS_FMT_VYUY8_2X8,
  };
  
  /*
   *  Camera input interface subdev operations
   */
  
  static int s3c_camif_subdev_enum_mbus_code(struct v4l2_subdev *sd,
  					struct v4l2_subdev_pad_config *cfg,
  					struct v4l2_subdev_mbus_code_enum *code)
  {
  	if (code->index >= ARRAY_SIZE(camif_mbus_formats))
  		return -EINVAL;
  
  	code->code = camif_mbus_formats[code->index];
  	return 0;
  }
  
  static int s3c_camif_subdev_get_fmt(struct v4l2_subdev *sd,
  				    struct v4l2_subdev_pad_config *cfg,
  				    struct v4l2_subdev_format *fmt)
  {
  	struct camif_dev *camif = v4l2_get_subdevdata(sd);
  	struct v4l2_mbus_framefmt *mf = &fmt->format;
  
  	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
  		mf = v4l2_subdev_get_try_format(sd, cfg, fmt->pad);
  		fmt->format = *mf;
  		return 0;
  	}
  
  	mutex_lock(&camif->lock);
  
  	switch (fmt->pad) {
  	case CAMIF_SD_PAD_SINK:
  		/* full camera input pixel size */
  		*mf = camif->mbus_fmt;
  		break;
  
  	case CAMIF_SD_PAD_SOURCE_C...CAMIF_SD_PAD_SOURCE_P:
  		/* crop rectangle at camera interface input */
  		mf->width = camif->camif_crop.width;
  		mf->height = camif->camif_crop.height;
  		mf->code = camif->mbus_fmt.code;
  		break;
  	}
  
  	mutex_unlock(&camif->lock);
  	mf->field = V4L2_FIELD_NONE;
  	mf->colorspace = V4L2_COLORSPACE_JPEG;
  	return 0;
  }
  
  static void __camif_subdev_try_format(struct camif_dev *camif,
  				struct v4l2_mbus_framefmt *mf, int pad)
  {
  	const struct s3c_camif_variant *variant = camif->variant;
  	const struct vp_pix_limits *pix_lim;
  	unsigned int i;
  
  	/* FIXME: constraints against codec or preview path ? */
  	pix_lim = &variant->vp_pix_limits[VP_CODEC];
  
  	for (i = 0; i < ARRAY_SIZE(camif_mbus_formats); i++)
  		if (camif_mbus_formats[i] == mf->code)
  			break;
  
  	if (i == ARRAY_SIZE(camif_mbus_formats))
  		mf->code = camif_mbus_formats[0];
  
  	if (pad == CAMIF_SD_PAD_SINK) {
  		v4l_bound_align_image(&mf->width, 8, CAMIF_MAX_PIX_WIDTH,
  				      ffs(pix_lim->out_width_align) - 1,
  				      &mf->height, 8, CAMIF_MAX_PIX_HEIGHT, 0,
  				      0);
  	} else {
  		struct v4l2_rect *crop = &camif->camif_crop;
  		v4l_bound_align_image(&mf->width, 8, crop->width,
  				      ffs(pix_lim->out_width_align) - 1,
  				      &mf->height, 8, crop->height,
  				      0, 0);
  	}
  
  	v4l2_dbg(1, debug, &camif->subdev, "%ux%u\n", mf->width, mf->height);
  }
  
  static int s3c_camif_subdev_set_fmt(struct v4l2_subdev *sd,
  				    struct v4l2_subdev_pad_config *cfg,
  				    struct v4l2_subdev_format *fmt)
  {
  	struct camif_dev *camif = v4l2_get_subdevdata(sd);
  	struct v4l2_mbus_framefmt *mf = &fmt->format;
  	struct v4l2_rect *crop = &camif->camif_crop;
  	int i;
  
  	v4l2_dbg(1, debug, sd, "pad%d: code: 0x%x, %ux%u\n",
  		 fmt->pad, mf->code, mf->width, mf->height);
  
  	mf->field = V4L2_FIELD_NONE;
  	mf->colorspace = V4L2_COLORSPACE_JPEG;
  	mutex_lock(&camif->lock);
  
  	/*
  	 * No pixel format change at the camera input is allowed
  	 * while streaming.
  	 */
  	if (vb2_is_busy(&camif->vp[VP_CODEC].vb_queue) ||
  	    vb2_is_busy(&camif->vp[VP_PREVIEW].vb_queue)) {
  		mutex_unlock(&camif->lock);
  		return -EBUSY;
  	}
  
  	__camif_subdev_try_format(camif, mf, fmt->pad);
  
  	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
  		mf = v4l2_subdev_get_try_format(sd, cfg, fmt->pad);
  		*mf = fmt->format;
  		mutex_unlock(&camif->lock);
  		return 0;
  	}
  
  	switch (fmt->pad) {
  	case CAMIF_SD_PAD_SINK:
  		camif->mbus_fmt = *mf;
  		/* Reset sink crop rectangle. */
  		crop->width = mf->width;
  		crop->height = mf->height;
  		crop->left = 0;
  		crop->top = 0;
  		/*
  		 * Reset source format (the camif's crop rectangle)
  		 * and the video output resolution.
  		 */
  		for (i = 0; i < CAMIF_VP_NUM; i++) {
  			struct camif_frame *frame = &camif->vp[i].out_frame;
  			frame->rect = *crop;
  			frame->f_width = mf->width;
  			frame->f_height = mf->height;
  		}
  		break;
  
  	case CAMIF_SD_PAD_SOURCE_C...CAMIF_SD_PAD_SOURCE_P:
  		/* Pixel format can be only changed on the sink pad. */
  		mf->code = camif->mbus_fmt.code;
  		mf->width = crop->width;
  		mf->height = crop->height;
  		break;
  	}
  
  	mutex_unlock(&camif->lock);
  	return 0;
  }
  
  static int s3c_camif_subdev_get_selection(struct v4l2_subdev *sd,
  					  struct v4l2_subdev_pad_config *cfg,
  					  struct v4l2_subdev_selection *sel)
  {
  	struct camif_dev *camif = v4l2_get_subdevdata(sd);
  	struct v4l2_rect *crop = &camif->camif_crop;
  	struct v4l2_mbus_framefmt *mf = &camif->mbus_fmt;
  
  	if ((sel->target != V4L2_SEL_TGT_CROP &&
  	    sel->target != V4L2_SEL_TGT_CROP_BOUNDS) ||
  	    sel->pad != CAMIF_SD_PAD_SINK)
  		return -EINVAL;
  
  	if (sel->which == V4L2_SUBDEV_FORMAT_TRY) {
  		sel->r = *v4l2_subdev_get_try_crop(sd, cfg, sel->pad);
  		return 0;
  	}
  
  	mutex_lock(&camif->lock);
  
  	if (sel->target == V4L2_SEL_TGT_CROP) {
  		sel->r = *crop;
  	} else { /* crop bounds */
  		sel->r.width = mf->width;
  		sel->r.height = mf->height;
  		sel->r.left = 0;
  		sel->r.top = 0;
  	}
  
  	mutex_unlock(&camif->lock);
  
  	v4l2_dbg(1, debug, sd, "%s: crop: (%d,%d) %dx%d, size: %ux%u\n",
  		 __func__, crop->left, crop->top, crop->width,
  		 crop->height, mf->width, mf->height);
  
  	return 0;
  }
  
  static void __camif_try_crop(struct camif_dev *camif, struct v4l2_rect *r)
  {
  	struct v4l2_mbus_framefmt *mf = &camif->mbus_fmt;
  	const struct camif_pix_limits *pix_lim = &camif->variant->pix_limits;
  	unsigned int left = 2 * r->left;
  	unsigned int top = 2 * r->top;
  
  	/*
  	 * Following constraints must be met:
  	 *  - r->width + 2 * r->left = mf->width;
  	 *  - r->height + 2 * r->top = mf->height;
  	 *  - crop rectangle size and position must be aligned
  	 *    to 8 or 2 pixels, depending on SoC version.
  	 */
  	v4l_bound_align_image(&r->width, 0, mf->width,
  			      ffs(pix_lim->win_hor_offset_align) - 1,
  			      &r->height, 0, mf->height, 1, 0);
  
  	v4l_bound_align_image(&left, 0, mf->width - r->width,
  			      ffs(pix_lim->win_hor_offset_align),
  			      &top, 0, mf->height - r->height, 2, 0);
  
  	r->left = left / 2;
  	r->top = top / 2;
  	r->width = mf->width - left;
  	r->height = mf->height - top;
  	/*
  	 * Make sure we either downscale or upscale both the pixel
  	 * width and height. Just return current crop rectangle if
  	 * this scaler constraint is not met.
  	 */
  	if (camif->variant->ip_revision == S3C244X_CAMIF_IP_REV &&
  	    camif_is_streaming(camif)) {
  		unsigned int i;
  
  		for (i = 0; i < CAMIF_VP_NUM; i++) {
  			struct v4l2_rect *or = &camif->vp[i].out_frame.rect;
  			if ((or->width > r->width) == (or->height > r->height))
  				continue;
  			*r = camif->camif_crop;
  			pr_debug("Width/height scaling direction limitation\n");
  			break;
  		}
  	}
  
  	v4l2_dbg(1, debug, &camif->v4l2_dev, "crop: (%d,%d)/%dx%d, fmt: %ux%u\n",
  		 r->left, r->top, r->width, r->height, mf->width, mf->height);
  }
  
  static int s3c_camif_subdev_set_selection(struct v4l2_subdev *sd,
  					  struct v4l2_subdev_pad_config *cfg,
  					  struct v4l2_subdev_selection *sel)
  {
  	struct camif_dev *camif = v4l2_get_subdevdata(sd);
  	struct v4l2_rect *crop = &camif->camif_crop;
  	struct camif_scaler scaler;
  
  	if (sel->target != V4L2_SEL_TGT_CROP || sel->pad != CAMIF_SD_PAD_SINK)
  		return -EINVAL;
  
  	mutex_lock(&camif->lock);
  	__camif_try_crop(camif, &sel->r);
  
  	if (sel->which == V4L2_SUBDEV_FORMAT_TRY) {
  		*v4l2_subdev_get_try_crop(sd, cfg, sel->pad) = sel->r;
  	} else {
  		unsigned long flags;
  		unsigned int i;
  
  		spin_lock_irqsave(&camif->slock, flags);
  		*crop = sel->r;
  
  		for (i = 0; i < CAMIF_VP_NUM; i++) {
  			struct camif_vp *vp = &camif->vp[i];
  			scaler = vp->scaler;
  			if (s3c_camif_get_scaler_config(vp, &scaler))
  				continue;
  			vp->scaler = scaler;
  			vp->state |= ST_VP_CONFIG;
  		}
  
  		spin_unlock_irqrestore(&camif->slock, flags);
  	}
  	mutex_unlock(&camif->lock);
  
  	v4l2_dbg(1, debug, sd, "%s: (%d,%d) %dx%d, f_w: %u, f_h: %u\n",
  		 __func__, crop->left, crop->top, crop->width, crop->height,
  		 camif->mbus_fmt.width, camif->mbus_fmt.height);
  
  	return 0;
  }
  
  static const struct v4l2_subdev_pad_ops s3c_camif_subdev_pad_ops = {
  	.enum_mbus_code = s3c_camif_subdev_enum_mbus_code,
  	.get_selection = s3c_camif_subdev_get_selection,
  	.set_selection = s3c_camif_subdev_set_selection,
  	.get_fmt = s3c_camif_subdev_get_fmt,
  	.set_fmt = s3c_camif_subdev_set_fmt,
  };
  
  static const struct v4l2_subdev_ops s3c_camif_subdev_ops = {
  	.pad = &s3c_camif_subdev_pad_ops,
  };
  
  static int s3c_camif_subdev_s_ctrl(struct v4l2_ctrl *ctrl)
  {
  	struct camif_dev *camif = container_of(ctrl->handler, struct camif_dev,
  					       ctrl_handler);
  	unsigned long flags;
  
  	spin_lock_irqsave(&camif->slock, flags);
  
  	switch (ctrl->id) {
  	case V4L2_CID_COLORFX:
  		camif->colorfx = camif->ctrl_colorfx->val;
  		/* Set Cb, Cr */
  		switch (ctrl->val) {
  		case V4L2_COLORFX_SEPIA:
  			camif->colorfx_cb = 115;
  			camif->colorfx_cr = 145;
  			break;
  		case V4L2_COLORFX_SET_CBCR:
  			camif->colorfx_cb = camif->ctrl_colorfx_cbcr->val >> 8;
  			camif->colorfx_cr = camif->ctrl_colorfx_cbcr->val & 0xff;
  			break;
  		default:
  			/* for V4L2_COLORFX_BW and others */
  			camif->colorfx_cb = 128;
  			camif->colorfx_cr = 128;
  		}
  		break;
  	case V4L2_CID_TEST_PATTERN:
  		camif->test_pattern = camif->ctrl_test_pattern->val;
  		break;
  	default:
  		WARN_ON(1);
  	}
  
  	camif->vp[VP_CODEC].state |= ST_VP_CONFIG;
  	camif->vp[VP_PREVIEW].state |= ST_VP_CONFIG;
  	spin_unlock_irqrestore(&camif->slock, flags);
  
  	return 0;
  }
  
  static const struct v4l2_ctrl_ops s3c_camif_subdev_ctrl_ops = {
  	.s_ctrl	= s3c_camif_subdev_s_ctrl,
  };
  
  static const char * const s3c_camif_test_pattern_menu[] = {
  	"Disabled",
  	"Color bars",
  	"Horizontal increment",
  	"Vertical increment",
  };
  
  int s3c_camif_create_subdev(struct camif_dev *camif)
  {
  	struct v4l2_ctrl_handler *handler = &camif->ctrl_handler;
  	struct v4l2_subdev *sd = &camif->subdev;
  	int ret;
  
  	v4l2_subdev_init(sd, &s3c_camif_subdev_ops);
  	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
  	strlcpy(sd->name, "S3C-CAMIF", sizeof(sd->name));
  
  	camif->pads[CAMIF_SD_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
  	camif->pads[CAMIF_SD_PAD_SOURCE_C].flags = MEDIA_PAD_FL_SOURCE;
  	camif->pads[CAMIF_SD_PAD_SOURCE_P].flags = MEDIA_PAD_FL_SOURCE;
  
  	ret = media_entity_pads_init(&sd->entity, CAMIF_SD_PADS_NUM,
  				camif->pads);
  	if (ret)
  		return ret;
  
  	v4l2_ctrl_handler_init(handler, 3);
  	camif->ctrl_test_pattern = v4l2_ctrl_new_std_menu_items(handler,
  			&s3c_camif_subdev_ctrl_ops, V4L2_CID_TEST_PATTERN,
  			ARRAY_SIZE(s3c_camif_test_pattern_menu) - 1, 0, 0,
  			s3c_camif_test_pattern_menu);
  
  	if (camif->variant->has_img_effect) {
  		camif->ctrl_colorfx = v4l2_ctrl_new_std_menu(handler,
  				&s3c_camif_subdev_ctrl_ops,
  				V4L2_CID_COLORFX, V4L2_COLORFX_SET_CBCR,
  				~0x981f, V4L2_COLORFX_NONE);
  
  		camif->ctrl_colorfx_cbcr = v4l2_ctrl_new_std(handler,
  				&s3c_camif_subdev_ctrl_ops,
  				V4L2_CID_COLORFX_CBCR, 0, 0xffff, 1, 0);
  	}
  
  	if (handler->error) {
  		v4l2_ctrl_handler_free(handler);
  		media_entity_cleanup(&sd->entity);
  		return handler->error;
  	}
  
  	if (camif->variant->has_img_effect)
  		v4l2_ctrl_auto_cluster(2, &camif->ctrl_colorfx,
  			       V4L2_COLORFX_SET_CBCR, false);
  
  	sd->ctrl_handler = handler;
  	v4l2_set_subdevdata(sd, camif);
  
  	return 0;
  }
  
  void s3c_camif_unregister_subdev(struct camif_dev *camif)
  {
  	struct v4l2_subdev *sd = &camif->subdev;
  
  	/* Return if not registered */
  	if (v4l2_get_subdevdata(sd) == NULL)
  		return;
  
  	v4l2_device_unregister_subdev(sd);
  	media_entity_cleanup(&sd->entity);
  	v4l2_ctrl_handler_free(&camif->ctrl_handler);
  	v4l2_set_subdevdata(sd, NULL);
  }
  
  int s3c_camif_set_defaults(struct camif_dev *camif)
  {
  	unsigned int ip_rev = camif->variant->ip_revision;
  	int i;
  
  	for (i = 0; i < CAMIF_VP_NUM; i++) {
  		struct camif_vp *vp = &camif->vp[i];
  		struct camif_frame *f = &vp->out_frame;
  
  		vp->camif = camif;
  		vp->id = i;
  		vp->offset = camif->variant->vp_offset;
  
  		if (ip_rev == S3C244X_CAMIF_IP_REV)
  			vp->fmt_flags = i ? FMT_FL_S3C24XX_PREVIEW :
  					FMT_FL_S3C24XX_CODEC;
  		else
  			vp->fmt_flags = FMT_FL_S3C64XX;
  
  		vp->out_fmt = s3c_camif_find_format(vp, NULL, 0);
  		BUG_ON(vp->out_fmt == NULL);
  
  		memset(f, 0, sizeof(*f));
  		f->f_width = CAMIF_DEF_WIDTH;
  		f->f_height = CAMIF_DEF_HEIGHT;
  		f->rect.width = CAMIF_DEF_WIDTH;
  		f->rect.height = CAMIF_DEF_HEIGHT;
  
  		/* Scaler is always enabled */
  		vp->scaler.enable = 1;
  
  		vp->payload = (f->f_width * f->f_height *
  			       vp->out_fmt->depth) / 8;
  	}
  
  	memset(&camif->mbus_fmt, 0, sizeof(camif->mbus_fmt));
  	camif->mbus_fmt.width = CAMIF_DEF_WIDTH;
  	camif->mbus_fmt.height = CAMIF_DEF_HEIGHT;
  	camif->mbus_fmt.code  = camif_mbus_formats[0];
  
  	memset(&camif->camif_crop, 0, sizeof(camif->camif_crop));
  	camif->camif_crop.width = CAMIF_DEF_WIDTH;
  	camif->camif_crop.height = CAMIF_DEF_HEIGHT;
  
  	return 0;
  }
  