text: // SPDX-License-Identifier: GPL-2.0
  /*
   * camss-video.c
   *
   * Qualcomm MSM Camera Subsystem - V4L2 device node
   *
   * Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
   * Copyright (C) 2015-2018 Linaro Ltd.
   */
  #include <linux/slab.h>
  #include <media/media-entity.h>
  #include <media/v4l2-dev.h>
  #include <media/v4l2-device.h>
  #include <media/v4l2-ioctl.h>
  #include <media/v4l2-mc.h>
  #include <media/videobuf2-dma-sg.h>
  
  #include "camss-video.h"
  #include "camss.h"
  
  struct fract {
  	u8 numerator;
  	u8 denominator;
  };
  
  /*
   * struct camss_format_info - ISP media bus format information
   * @code: V4L2 media bus format code
   * @pixelformat: V4L2 pixel format FCC identifier
   * @planes: Number of planes
   * @hsub: Horizontal subsampling (for each plane)
   * @vsub: Vertical subsampling (for each plane)
   * @bpp: Bits per pixel when stored in memory (for each plane)
   */
  struct camss_format_info {
  	u32 code;
  	u32 pixelformat;
  	u8 planes;
  	struct fract hsub[3];
  	struct fract vsub[3];
  	unsigned int bpp[3];
  };
  
  static const struct camss_format_info formats_rdi_8x16[] = {
  	{ MEDIA_BUS_FMT_UYVY8_2X8, V4L2_PIX_FMT_UYVY, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_VYUY8_2X8, V4L2_PIX_FMT_VYUY, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_YUYV8_2X8, V4L2_PIX_FMT_YUYV, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_YVYU8_2X8, V4L2_PIX_FMT_YVYU, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_SBGGR8_1X8, V4L2_PIX_FMT_SBGGR8, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 8 } },
  	{ MEDIA_BUS_FMT_SGBRG8_1X8, V4L2_PIX_FMT_SGBRG8, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 8 } },
  	{ MEDIA_BUS_FMT_SGRBG8_1X8, V4L2_PIX_FMT_SGRBG8, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 8 } },
  	{ MEDIA_BUS_FMT_SRGGB8_1X8, V4L2_PIX_FMT_SRGGB8, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 8 } },
  	{ MEDIA_BUS_FMT_SBGGR10_1X10, V4L2_PIX_FMT_SBGGR10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_SGBRG10_1X10, V4L2_PIX_FMT_SGBRG10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_SGRBG10_1X10, V4L2_PIX_FMT_SGRBG10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_SRGGB10_1X10, V4L2_PIX_FMT_SRGGB10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_SBGGR12_1X12, V4L2_PIX_FMT_SBGGR12P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 12 } },
  	{ MEDIA_BUS_FMT_SGBRG12_1X12, V4L2_PIX_FMT_SGBRG12P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 12 } },
  	{ MEDIA_BUS_FMT_SGRBG12_1X12, V4L2_PIX_FMT_SGRBG12P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 12 } },
  	{ MEDIA_BUS_FMT_SRGGB12_1X12, V4L2_PIX_FMT_SRGGB12P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 12 } },
  	{ MEDIA_BUS_FMT_Y10_1X10, V4L2_PIX_FMT_Y10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  };
  
  static const struct camss_format_info formats_rdi_8x96[] = {
  	{ MEDIA_BUS_FMT_UYVY8_2X8, V4L2_PIX_FMT_UYVY, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_VYUY8_2X8, V4L2_PIX_FMT_VYUY, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_YUYV8_2X8, V4L2_PIX_FMT_YUYV, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_YVYU8_2X8, V4L2_PIX_FMT_YVYU, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_SBGGR8_1X8, V4L2_PIX_FMT_SBGGR8, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 8 } },
  	{ MEDIA_BUS_FMT_SGBRG8_1X8, V4L2_PIX_FMT_SGBRG8, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 8 } },
  	{ MEDIA_BUS_FMT_SGRBG8_1X8, V4L2_PIX_FMT_SGRBG8, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 8 } },
  	{ MEDIA_BUS_FMT_SRGGB8_1X8, V4L2_PIX_FMT_SRGGB8, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 8 } },
  	{ MEDIA_BUS_FMT_SBGGR10_1X10, V4L2_PIX_FMT_SBGGR10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_SGBRG10_1X10, V4L2_PIX_FMT_SGBRG10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_SGRBG10_1X10, V4L2_PIX_FMT_SGRBG10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_SRGGB10_1X10, V4L2_PIX_FMT_SRGGB10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_SBGGR10_2X8_PADHI_LE, V4L2_PIX_FMT_SBGGR10, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_SBGGR12_1X12, V4L2_PIX_FMT_SBGGR12P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 12 } },
  	{ MEDIA_BUS_FMT_SGBRG12_1X12, V4L2_PIX_FMT_SGBRG12P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 12 } },
  	{ MEDIA_BUS_FMT_SGRBG12_1X12, V4L2_PIX_FMT_SGRBG12P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 12 } },
  	{ MEDIA_BUS_FMT_SRGGB12_1X12, V4L2_PIX_FMT_SRGGB12P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 12 } },
  	{ MEDIA_BUS_FMT_SBGGR14_1X14, V4L2_PIX_FMT_SBGGR14P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 14 } },
  	{ MEDIA_BUS_FMT_SGBRG14_1X14, V4L2_PIX_FMT_SGBRG14P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 14 } },
  	{ MEDIA_BUS_FMT_SGRBG14_1X14, V4L2_PIX_FMT_SGRBG14P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 14 } },
  	{ MEDIA_BUS_FMT_SRGGB14_1X14, V4L2_PIX_FMT_SRGGB14P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 14 } },
  	{ MEDIA_BUS_FMT_Y10_1X10, V4L2_PIX_FMT_Y10P, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 10 } },
  	{ MEDIA_BUS_FMT_Y10_2X8_PADHI_LE, V4L2_PIX_FMT_Y10, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  };
  
  static const struct camss_format_info formats_pix_8x16[] = {
  	{ MEDIA_BUS_FMT_YUYV8_1_5X8, V4L2_PIX_FMT_NV12, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YVYU8_1_5X8, V4L2_PIX_FMT_NV12, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_1_5X8, V4L2_PIX_FMT_NV12, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_VYUY8_1_5X8, V4L2_PIX_FMT_NV12, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YUYV8_1_5X8, V4L2_PIX_FMT_NV21, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YVYU8_1_5X8, V4L2_PIX_FMT_NV21, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_1_5X8, V4L2_PIX_FMT_NV21, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_VYUY8_1_5X8, V4L2_PIX_FMT_NV21, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YUYV8_2X8, V4L2_PIX_FMT_NV16, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YVYU8_2X8, V4L2_PIX_FMT_NV16, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_2X8, V4L2_PIX_FMT_NV16, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_VYUY8_2X8, V4L2_PIX_FMT_NV16, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YUYV8_2X8, V4L2_PIX_FMT_NV61, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YVYU8_2X8, V4L2_PIX_FMT_NV61, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_2X8, V4L2_PIX_FMT_NV61, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_VYUY8_2X8, V4L2_PIX_FMT_NV61, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  };
  
  static const struct camss_format_info formats_pix_8x96[] = {
  	{ MEDIA_BUS_FMT_YUYV8_1_5X8, V4L2_PIX_FMT_NV12, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YVYU8_1_5X8, V4L2_PIX_FMT_NV12, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_1_5X8, V4L2_PIX_FMT_NV12, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_VYUY8_1_5X8, V4L2_PIX_FMT_NV12, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YUYV8_1_5X8, V4L2_PIX_FMT_NV21, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YVYU8_1_5X8, V4L2_PIX_FMT_NV21, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_1_5X8, V4L2_PIX_FMT_NV21, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_VYUY8_1_5X8, V4L2_PIX_FMT_NV21, 1,
  	  { { 1, 1 } }, { { 2, 3 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YUYV8_2X8, V4L2_PIX_FMT_NV16, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YVYU8_2X8, V4L2_PIX_FMT_NV16, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_2X8, V4L2_PIX_FMT_NV16, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_VYUY8_2X8, V4L2_PIX_FMT_NV16, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YUYV8_2X8, V4L2_PIX_FMT_NV61, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_YVYU8_2X8, V4L2_PIX_FMT_NV61, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_2X8, V4L2_PIX_FMT_NV61, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_VYUY8_2X8, V4L2_PIX_FMT_NV61, 1,
  	  { { 1, 1 } }, { { 1, 2 } }, { 8 } },
  	{ MEDIA_BUS_FMT_UYVY8_2X8, V4L2_PIX_FMT_UYVY, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_VYUY8_2X8, V4L2_PIX_FMT_VYUY, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_YUYV8_2X8, V4L2_PIX_FMT_YUYV, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  	{ MEDIA_BUS_FMT_YVYU8_2X8, V4L2_PIX_FMT_YVYU, 1,
  	  { { 1, 1 } }, { { 1, 1 } }, { 16 } },
  };
  
  /* -----------------------------------------------------------------------------
   * Helper functions
   */
  
  static int video_find_format(u32 code, u32 pixelformat,
  			     const struct camss_format_info *formats,
  			     unsigned int nformats)
  {
  	int i;
  
  	for (i = 0; i < nformats; i++) {
  		if (formats[i].code == code &&
  		    formats[i].pixelformat == pixelformat)
  			return i;
  	}
  
  	for (i = 0; i < nformats; i++)
  		if (formats[i].code == code)
  			return i;
  
  	WARN_ON(1);
  
  	return -EINVAL;
  }
  
  /*
   * video_mbus_to_pix_mp - Convert v4l2_mbus_framefmt to v4l2_pix_format_mplane
   * @mbus: v4l2_mbus_framefmt format (input)
   * @pix: v4l2_pix_format_mplane format (output)
   * @f: a pointer to formats array element to be used for the conversion
   * @alignment: bytesperline alignment value
   *
   * Fill the output pix structure with information from the input mbus format.
   *
   * Return 0 on success or a negative error code otherwise
   */
  static int video_mbus_to_pix_mp(const struct v4l2_mbus_framefmt *mbus,
  				struct v4l2_pix_format_mplane *pix,
  				const struct camss_format_info *f,
  				unsigned int alignment)
  {
  	unsigned int i;
  	u32 bytesperline;
  
  	memset(pix, 0, sizeof(*pix));
  	v4l2_fill_pix_format_mplane(pix, mbus);
  	pix->pixelformat = f->pixelformat;
  	pix->num_planes = f->planes;
  	for (i = 0; i < pix->num_planes; i++) {
  		bytesperline = pix->width / f->hsub[i].numerator *
  			f->hsub[i].denominator * f->bpp[i] / 8;
  		bytesperline = ALIGN(bytesperline, alignment);
  		pix->plane_fmt[i].bytesperline = bytesperline;
  		pix->plane_fmt[i].sizeimage = pix->height /
  				f->vsub[i].numerator * f->vsub[i].denominator *
  				bytesperline;
  	}
  
  	return 0;
  }
  
  static struct v4l2_subdev *video_remote_subdev(struct camss_video *video,
  					       u32 *pad)
  {
  	struct media_pad *remote;
  
  	remote = media_entity_remote_pad(&video->pad);
  
  	if (!remote || !is_media_entity_v4l2_subdev(remote->entity))
  		return NULL;
  
  	if (pad)
  		*pad = remote->index;
  
  	return media_entity_to_v4l2_subdev(remote->entity);
  }
  
  static int video_get_subdev_format(struct camss_video *video,
  				   struct v4l2_format *format)
  {
  	struct v4l2_subdev_format fmt;
  	struct v4l2_subdev *subdev;
  	u32 pad;
  	int ret;
  
  	subdev = video_remote_subdev(video, &pad);
  	if (subdev == NULL)
  		return -EPIPE;
  
  	fmt.pad = pad;
  	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
  
  	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);
  	if (ret)
  		return ret;
  
  	ret = video_find_format(fmt.format.code,
  				format->fmt.pix_mp.pixelformat,
  				video->formats, video->nformats);
  	if (ret < 0)
  		return ret;
  
  	format->type = video->type;
  
  	return video_mbus_to_pix_mp(&fmt.format, &format->fmt.pix_mp,
  				    &video->formats[ret], video->bpl_alignment);
  }
  
  /* -----------------------------------------------------------------------------
   * Video queue operations
   */
  
  static int video_queue_setup(struct vb2_queue *q,
  	unsigned int *num_buffers, unsigned int *num_planes,
  	unsigned int sizes[], struct device *alloc_devs[])
  {
  	struct camss_video *video = vb2_get_drv_priv(q);
  	const struct v4l2_pix_format_mplane *format =
  						&video->active_fmt.fmt.pix_mp;
  	unsigned int i;
  
  	if (*num_planes) {
  		if (*num_planes != format->num_planes)
  			return -EINVAL;
  
  		for (i = 0; i < *num_planes; i++)
  			if (sizes[i] < format->plane_fmt[i].sizeimage)
  				return -EINVAL;
  
  		return 0;
  	}
  
  	*num_planes = format->num_planes;
  
  	for (i = 0; i < *num_planes; i++)
  		sizes[i] = format->plane_fmt[i].sizeimage;
  
  	return 0;
  }
  
  static int video_buf_init(struct vb2_buffer *vb)
  {
  	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  	struct camss_video *video = vb2_get_drv_priv(vb->vb2_queue);
  	struct camss_buffer *buffer = container_of(vbuf, struct camss_buffer,
  						   vb);
  	const struct v4l2_pix_format_mplane *format =
  						&video->active_fmt.fmt.pix_mp;
  	struct sg_table *sgt;
  	unsigned int i;
  
  	for (i = 0; i < format->num_planes; i++) {
  		sgt = vb2_dma_sg_plane_desc(vb, i);
  		if (!sgt)
  			return -EFAULT;
  
  		buffer->addr[i] = sg_dma_address(sgt->sgl);
  	}
  
  	if (format->pixelformat == V4L2_PIX_FMT_NV12 ||
  			format->pixelformat == V4L2_PIX_FMT_NV21 ||
  			format->pixelformat == V4L2_PIX_FMT_NV16 ||
  			format->pixelformat == V4L2_PIX_FMT_NV61)
  		buffer->addr[1] = buffer->addr[0] +
  				format->plane_fmt[0].bytesperline *
  				format->height;
  
  	return 0;
  }
  
  static int video_buf_prepare(struct vb2_buffer *vb)
  {
  	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  	struct camss_video *video = vb2_get_drv_priv(vb->vb2_queue);
  	const struct v4l2_pix_format_mplane *format =
  						&video->active_fmt.fmt.pix_mp;
  	unsigned int i;
  
  	for (i = 0; i < format->num_planes; i++) {
  		if (format->plane_fmt[i].sizeimage > vb2_plane_size(vb, i))
  			return -EINVAL;
  
  		vb2_set_plane_payload(vb, i, format->plane_fmt[i].sizeimage);
  	}
  
  	vbuf->field = V4L2_FIELD_NONE;
  
  	return 0;
  }
  
  static void video_buf_queue(struct vb2_buffer *vb)
  {
  	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
  	struct camss_video *video = vb2_get_drv_priv(vb->vb2_queue);
  	struct camss_buffer *buffer = container_of(vbuf, struct camss_buffer,
  						   vb);
  
  	video->ops->queue_buffer(video, buffer);
  }
  
  static int video_check_format(struct camss_video *video)
  {
  	struct v4l2_pix_format_mplane *pix = &video->active_fmt.fmt.pix_mp;
  	struct v4l2_format format;
  	struct v4l2_pix_format_mplane *sd_pix = &format.fmt.pix_mp;
  	int ret;
  
  	sd_pix->pixelformat = pix->pixelformat;
  	ret = video_get_subdev_format(video, &format);
  	if (ret < 0)
  		return ret;
  
  	if (pix->pixelformat != sd_pix->pixelformat ||
  	    pix->height != sd_pix->height ||
  	    pix->width != sd_pix->width ||
  	    pix->num_planes != sd_pix->num_planes ||
  	    pix->field != format.fmt.pix_mp.field)
  		return -EPIPE;
  
  	return 0;
  }
  
  static int video_start_streaming(struct vb2_queue *q, unsigned int count)
  {
  	struct camss_video *video = vb2_get_drv_priv(q);
  	struct video_device *vdev = &video->vdev;
  	struct media_entity *entity;
  	struct media_pad *pad;
  	struct v4l2_subdev *subdev;
  	int ret;
  
  	ret = media_pipeline_start(&vdev->entity, &video->pipe);
  	if (ret < 0)
  		return ret;
  
  	ret = video_check_format(video);
  	if (ret < 0)
  		goto error;
  
  	entity = &vdev->entity;
  	while (1) {
  		pad = &entity->pads[0];
  		if (!(pad->flags & MEDIA_PAD_FL_SINK))
  			break;
  
  		pad = media_entity_remote_pad(pad);
  		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
  			break;
  
  		entity = pad->entity;
  		subdev = media_entity_to_v4l2_subdev(entity);
  
  		ret = v4l2_subdev_call(subdev, video, s_stream, 1);
  		if (ret < 0 && ret != -ENOIOCTLCMD)
  			goto error;
  	}
  
  	return 0;
  
  error:
  	media_pipeline_stop(&vdev->entity);
  
  	video->ops->flush_buffers(video, VB2_BUF_STATE_QUEUED);
  
  	return ret;
  }
  
  static void video_stop_streaming(struct vb2_queue *q)
  {
  	struct camss_video *video = vb2_get_drv_priv(q);
  	struct video_device *vdev = &video->vdev;
  	struct media_entity *entity;
  	struct media_pad *pad;
  	struct v4l2_subdev *subdev;
  
  	entity = &vdev->entity;
  	while (1) {
  		pad = &entity->pads[0];
  		if (!(pad->flags & MEDIA_PAD_FL_SINK))
  			break;
  
  		pad = media_entity_remote_pad(pad);
  		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
  			break;
  
  		entity = pad->entity;
  		subdev = media_entity_to_v4l2_subdev(entity);
  
  		v4l2_subdev_call(subdev, video, s_stream, 0);
  	}
  
  	media_pipeline_stop(&vdev->entity);
  
  	video->ops->flush_buffers(video, VB2_BUF_STATE_ERROR);
  }
  
  static const struct vb2_ops msm_video_vb2_q_ops = {
  	.queue_setup     = video_queue_setup,
  	.wait_prepare    = vb2_ops_wait_prepare,
  	.wait_finish     = vb2_ops_wait_finish,
  	.buf_init        = video_buf_init,
  	.buf_prepare     = video_buf_prepare,
  	.buf_queue       = video_buf_queue,
  	.start_streaming = video_start_streaming,
  	.stop_streaming  = video_stop_streaming,
  };
  
  /* -----------------------------------------------------------------------------
   * V4L2 ioctls
   */
  
  static int video_querycap(struct file *file, void *fh,
  			  struct v4l2_capability *cap)
  {
  	struct camss_video *video = video_drvdata(file);
  
  	strscpy(cap->driver, "qcom-camss", sizeof(cap->driver));
  	strscpy(cap->card, "Qualcomm Camera Subsystem", sizeof(cap->card));
  	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
  		 dev_name(video->camss->dev));
  
  	return 0;
  }
  
  static int video_enum_fmt(struct file *file, void *fh, struct v4l2_fmtdesc *f)
  {
  	struct camss_video *video = video_drvdata(file);
  	int i, j, k;
  
  	if (f->type != video->type)
  		return -EINVAL;
  
  	if (f->index >= video->nformats)
  		return -EINVAL;
  
  	/* find index "i" of "k"th unique pixelformat in formats array */
  	k = -1;
  	for (i = 0; i < video->nformats; i++) {
  		for (j = 0; j < i; j++) {
  			if (video->formats[i].pixelformat ==
  					video->formats[j].pixelformat)
  				break;
  		}
  
  		if (j == i)
  			k++;
  
  		if (k == f->index)
  			break;
  	}
  
  	if (k < f->index)
  		return -EINVAL;
  
  	f->pixelformat = video->formats[i].pixelformat;
  
  	return 0;
  }
  
  static int video_g_fmt(struct file *file, void *fh, struct v4l2_format *f)
  {
  	struct camss_video *video = video_drvdata(file);
  
  	*f = video->active_fmt;
  
  	return 0;
  }
  
  static int __video_try_fmt(struct camss_video *video, struct v4l2_format *f)
  {
  	struct v4l2_pix_format_mplane *pix_mp;
  	const struct camss_format_info *fi;
  	struct v4l2_plane_pix_format *p;
  	u32 bytesperline[3] = { 0 };
  	u32 sizeimage[3] = { 0 };
  	u32 width, height;
  	u32 bpl, lines;
  	int i, j;
  
  	pix_mp = &f->fmt.pix_mp;
  
  	if (video->line_based)
  		for (i = 0; i < pix_mp->num_planes && i < 3; i++) {
  			p = &pix_mp->plane_fmt[i];
  			bytesperline[i] = clamp_t(u32, p->bytesperline,
  						  1, 65528);
  			sizeimage[i] = clamp_t(u32, p->sizeimage,
  					       bytesperline[i],
  					       bytesperline[i] * 4096);
  		}
  
  	for (j = 0; j < video->nformats; j++)
  		if (pix_mp->pixelformat == video->formats[j].pixelformat)
  			break;
  
  	if (j == video->nformats)
  		j = 0; /* default format */
  
  	fi = &video->formats[j];
  	width = pix_mp->width;
  	height = pix_mp->height;
  
  	memset(pix_mp, 0, sizeof(*pix_mp));
  
  	pix_mp->pixelformat = fi->pixelformat;
  	pix_mp->width = clamp_t(u32, width, 1, 8191);
  	pix_mp->height = clamp_t(u32, height, 1, 8191);
  	pix_mp->num_planes = fi->planes;
  	for (i = 0; i < pix_mp->num_planes; i++) {
  		bpl = pix_mp->width / fi->hsub[i].numerator *
  			fi->hsub[i].denominator * fi->bpp[i] / 8;
  		bpl = ALIGN(bpl, video->bpl_alignment);
  		pix_mp->plane_fmt[i].bytesperline = bpl;
  		pix_mp->plane_fmt[i].sizeimage = pix_mp->height /
  			fi->vsub[i].numerator * fi->vsub[i].denominator * bpl;
  	}
  
  	pix_mp->field = V4L2_FIELD_NONE;
  	pix_mp->colorspace = V4L2_COLORSPACE_SRGB;
  	pix_mp->flags = 0;
  	pix_mp->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(pix_mp->colorspace);
  	pix_mp->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true,
  					pix_mp->colorspace, pix_mp->ycbcr_enc);
  	pix_mp->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(pix_mp->colorspace);
  
  	if (video->line_based)
  		for (i = 0; i < pix_mp->num_planes; i++) {
  			p = &pix_mp->plane_fmt[i];
  			p->bytesperline = clamp_t(u32, p->bytesperline,
  						  1, 65528);
  			p->sizeimage = clamp_t(u32, p->sizeimage,
  					       p->bytesperline,
  					       p->bytesperline * 4096);
  			lines = p->sizeimage / p->bytesperline;
  
  			if (p->bytesperline < bytesperline[i])
  				p->bytesperline = ALIGN(bytesperline[i], 8);
  
  			if (p->sizeimage < p->bytesperline * lines)
  				p->sizeimage = p->bytesperline * lines;
  
  			if (p->sizeimage < sizeimage[i])
  				p->sizeimage = sizeimage[i];
  		}
  
  	return 0;
  }
  
  static int video_try_fmt(struct file *file, void *fh, struct v4l2_format *f)
  {
  	struct camss_video *video = video_drvdata(file);
  
  	return __video_try_fmt(video, f);
  }
  
  static int video_s_fmt(struct file *file, void *fh, struct v4l2_format *f)
  {
  	struct camss_video *video = video_drvdata(file);
  	int ret;
  
  	if (vb2_is_busy(&video->vb2_q))
  		return -EBUSY;
  
  	ret = __video_try_fmt(video, f);
  	if (ret < 0)
  		return ret;
  
  	video->active_fmt = *f;
  
  	return 0;
  }
  
  static int video_enum_input(struct file *file, void *fh,
  			    struct v4l2_input *input)
  {
  	if (input->index > 0)
  		return -EINVAL;
  
  	strscpy(input->name, "camera", sizeof(input->name));
  	input->type = V4L2_INPUT_TYPE_CAMERA;
  
  	return 0;
  }
  
  static int video_g_input(struct file *file, void *fh, unsigned int *input)
  {
  	*input = 0;
  
  	return 0;
  }
  
  static int video_s_input(struct file *file, void *fh, unsigned int input)
  {
  	return input == 0 ? 0 : -EINVAL;
  }
  
  static const struct v4l2_ioctl_ops msm_vid_ioctl_ops = {
  	.vidioc_querycap		= video_querycap,
  	.vidioc_enum_fmt_vid_cap	= video_enum_fmt,
  	.vidioc_g_fmt_vid_cap_mplane	= video_g_fmt,
  	.vidioc_s_fmt_vid_cap_mplane	= video_s_fmt,
  	.vidioc_try_fmt_vid_cap_mplane	= video_try_fmt,
  	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
  	.vidioc_querybuf		= vb2_ioctl_querybuf,
  	.vidioc_qbuf			= vb2_ioctl_qbuf,
  	.vidioc_expbuf			= vb2_ioctl_expbuf,
  	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
  	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
  	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
  	.vidioc_streamon		= vb2_ioctl_streamon,
  	.vidioc_streamoff		= vb2_ioctl_streamoff,
  	.vidioc_enum_input		= video_enum_input,
  	.vidioc_g_input			= video_g_input,
  	.vidioc_s_input			= video_s_input,
  };
  
  /* -----------------------------------------------------------------------------
   * V4L2 file operations
   */
  
  static int video_open(struct file *file)
  {
  	struct video_device *vdev = video_devdata(file);
  	struct camss_video *video = video_drvdata(file);
  	struct v4l2_fh *vfh;
  	int ret;
  
  	mutex_lock(&video->lock);
  
  	vfh = kzalloc(sizeof(*vfh), GFP_KERNEL);
  	if (vfh == NULL) {
  		ret = -ENOMEM;
  		goto error_alloc;
  	}
  
  	v4l2_fh_init(vfh, vdev);
  	v4l2_fh_add(vfh);
  
  	file->private_data = vfh;
  
  	ret = v4l2_pipeline_pm_get(&vdev->entity);
  	if (ret < 0) {
  		dev_err(video->camss->dev, "Failed to power up pipeline: %d\n",
  			ret);
  		goto error_pm_use;
  	}
  
  	mutex_unlock(&video->lock);
  
  	return 0;
  
  error_pm_use:
  	v4l2_fh_release(file);
  
  error_alloc:
  	mutex_unlock(&video->lock);
  
  	return ret;
  }
  
  static int video_release(struct file *file)
  {
  	struct video_device *vdev = video_devdata(file);
  
  	vb2_fop_release(file);
  
  	v4l2_pipeline_pm_put(&vdev->entity);
  
  	file->private_data = NULL;
  
  	return 0;
  }
  
  static const struct v4l2_file_operations msm_vid_fops = {
  	.owner          = THIS_MODULE,
  	.unlocked_ioctl = video_ioctl2,
  	.open           = video_open,
  	.release        = video_release,
  	.poll           = vb2_fop_poll,
  	.mmap		= vb2_fop_mmap,
  	.read		= vb2_fop_read,
  };
  
  /* -----------------------------------------------------------------------------
   * CAMSS video core
   */
  
  static void msm_video_release(struct video_device *vdev)
  {
  	struct camss_video *video = video_get_drvdata(vdev);
  
  	media_entity_cleanup(&vdev->entity);
  
  	mutex_destroy(&video->q_lock);
  	mutex_destroy(&video->lock);
  
  	if (atomic_dec_and_test(&video->camss->ref_count))
  		camss_delete(video->camss);
  }
  
  /*
   * msm_video_init_format - Helper function to initialize format
   * @video: struct camss_video
   *
   * Initialize pad format with default value.
   *
   * Return 0 on success or a negative error code otherwise
   */
  static int msm_video_init_format(struct camss_video *video)
  {
  	int ret;
  	struct v4l2_format format = {
  		.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE,
  		.fmt.pix_mp = {
  			.width = 1920,
  			.height = 1080,
  			.pixelformat = video->formats[0].pixelformat,
  		},
  	};
  
  	ret = __video_try_fmt(video, &format);
  	if (ret < 0)
  		return ret;
  
  	video->active_fmt = format;
  
  	return 0;
  }
  
  /*
   * msm_video_register - Register a video device node
   * @video: struct camss_video
   * @v4l2_dev: V4L2 device
   * @name: name to be used for the video device node
   *
   * Initialize and register a video device node to a V4L2 device. Also
   * initialize the vb2 queue.
   *
   * Return 0 on success or a negative error code otherwise
   */
  
  int msm_video_register(struct camss_video *video, struct v4l2_device *v4l2_dev,
  		       const char *name, int is_pix)
  {
  	struct media_pad *pad = &video->pad;
  	struct video_device *vdev;
  	struct vb2_queue *q;
  	int ret;
  
  	vdev = &video->vdev;
  
  	mutex_init(&video->q_lock);
  
  	q = &video->vb2_q;
  	q->drv_priv = video;
  	q->mem_ops = &vb2_dma_sg_memops;
  	q->ops = &msm_video_vb2_q_ops;
  	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
  	q->io_modes = VB2_DMABUF | VB2_MMAP | VB2_READ;
  	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
  	q->buf_struct_size = sizeof(struct camss_buffer);
  	q->dev = video->camss->dev;
  	q->lock = &video->q_lock;
  	ret = vb2_queue_init(q);
  	if (ret < 0) {
  		dev_err(v4l2_dev->dev, "Failed to init vb2 queue: %d\n", ret);
  		goto error_vb2_init;
  	}
  
  	pad->flags = MEDIA_PAD_FL_SINK;
  	ret = media_entity_pads_init(&vdev->entity, 1, pad);
  	if (ret < 0) {
  		dev_err(v4l2_dev->dev, "Failed to init video entity: %d\n",
  			ret);
  		goto error_media_init;
  	}
  
  	mutex_init(&video->lock);
  
  	if (video->camss->version == CAMSS_8x16) {
  		if (is_pix) {
  			video->formats = formats_pix_8x16;
  			video->nformats = ARRAY_SIZE(formats_pix_8x16);
  		} else {
  			video->formats = formats_rdi_8x16;
  			video->nformats = ARRAY_SIZE(formats_rdi_8x16);
  		}
  	} else if (video->camss->version == CAMSS_8x96) {
  		if (is_pix) {
  			video->formats = formats_pix_8x96;
  			video->nformats = ARRAY_SIZE(formats_pix_8x96);
  		} else {
  			video->formats = formats_rdi_8x96;
  			video->nformats = ARRAY_SIZE(formats_rdi_8x96);
  		}
  	} else {
  		goto error_video_register;
  	}
  
  	ret = msm_video_init_format(video);
  	if (ret < 0) {
  		dev_err(v4l2_dev->dev, "Failed to init format: %d\n", ret);
  		goto error_video_register;
  	}
  
  	vdev->fops = &msm_vid_fops;
  	vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_STREAMING |
  							V4L2_CAP_READWRITE;
  	vdev->ioctl_ops = &msm_vid_ioctl_ops;
  	vdev->release = msm_video_release;
  	vdev->v4l2_dev = v4l2_dev;
  	vdev->vfl_dir = VFL_DIR_RX;
  	vdev->queue = &video->vb2_q;
  	vdev->lock = &video->lock;
  	strscpy(vdev->name, name, sizeof(vdev->name));
  
  	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
  	if (ret < 0) {
  		dev_err(v4l2_dev->dev, "Failed to register video device: %d\n",
  			ret);
  		goto error_video_register;
  	}
  
  	video_set_drvdata(vdev, video);
  	atomic_inc(&video->camss->ref_count);
  
  	return 0;
  
  error_video_register:
  	media_entity_cleanup(&vdev->entity);
  	mutex_destroy(&video->lock);
  error_media_init:
  	vb2_queue_release(&video->vb2_q);
  error_vb2_init:
  	mutex_destroy(&video->q_lock);
  
  	return ret;
  }
  
  void msm_video_stop_streaming(struct camss_video *video)
  {
  	if (vb2_is_streaming(&video->vb2_q))
  		vb2_queue_release(&video->vb2_q);
  }
  
  void msm_video_unregister(struct camss_video *video)
  {
  	atomic_inc(&video->camss->ref_count);
  	video_unregister_device(&video->vdev);
  	atomic_dec(&video->camss->ref_count);
  }
  