text: /*
   * vsp1_sru.c  --  R-Car VSP1 Super Resolution Unit
   *
   * Copyright (C) 2013 Renesas Corporation
   *
   * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   */
  
  #include <linux/device.h>
  #include <linux/gfp.h>
  
  #include <media/v4l2-subdev.h>
  
  #include "vsp1.h"
  #include "vsp1_sru.h"
  
  #define SRU_MIN_SIZE				4U
  #define SRU_MAX_SIZE				8190U
  
  /* -----------------------------------------------------------------------------
   * Device Access
   */
  
  static inline u32 vsp1_sru_read(struct vsp1_sru *sru, u32 reg)
  {
  	return vsp1_read(sru->entity.vsp1, reg);
  }
  
  static inline void vsp1_sru_write(struct vsp1_sru *sru, u32 reg, u32 data)
  {
  	vsp1_write(sru->entity.vsp1, reg, data);
  }
  
  /* -----------------------------------------------------------------------------
   * Controls
   */
  
  #define V4L2_CID_VSP1_SRU_INTENSITY		(V4L2_CID_USER_BASE + 1)
  
  struct vsp1_sru_param {
  	u32 ctrl0;
  	u32 ctrl2;
  };
  
  #define VI6_SRU_CTRL0_PARAMS(p0, p1)			\
  	(((p0) << VI6_SRU_CTRL0_PARAM0_SHIFT) |		\
  	 ((p1) << VI6_SRU_CTRL0_PARAM1_SHIFT))
  
  #define VI6_SRU_CTRL2_PARAMS(p6, p7, p8)		\
  	(((p6) << VI6_SRU_CTRL2_PARAM6_SHIFT) |		\
  	 ((p7) << VI6_SRU_CTRL2_PARAM7_SHIFT) |		\
  	 ((p8) << VI6_SRU_CTRL2_PARAM8_SHIFT))
  
  static const struct vsp1_sru_param vsp1_sru_params[] = {
  	{
  		.ctrl0 = VI6_SRU_CTRL0_PARAMS(256, 4) | VI6_SRU_CTRL0_EN,
  		.ctrl2 = VI6_SRU_CTRL2_PARAMS(24, 40, 255),
  	}, {
  		.ctrl0 = VI6_SRU_CTRL0_PARAMS(256, 4) | VI6_SRU_CTRL0_EN,
  		.ctrl2 = VI6_SRU_CTRL2_PARAMS(8, 16, 255),
  	}, {
  		.ctrl0 = VI6_SRU_CTRL0_PARAMS(384, 5) | VI6_SRU_CTRL0_EN,
  		.ctrl2 = VI6_SRU_CTRL2_PARAMS(36, 60, 255),
  	}, {
  		.ctrl0 = VI6_SRU_CTRL0_PARAMS(384, 5) | VI6_SRU_CTRL0_EN,
  		.ctrl2 = VI6_SRU_CTRL2_PARAMS(12, 27, 255),
  	}, {
  		.ctrl0 = VI6_SRU_CTRL0_PARAMS(511, 6) | VI6_SRU_CTRL0_EN,
  		.ctrl2 = VI6_SRU_CTRL2_PARAMS(48, 80, 255),
  	}, {
  		.ctrl0 = VI6_SRU_CTRL0_PARAMS(511, 6) | VI6_SRU_CTRL0_EN,
  		.ctrl2 = VI6_SRU_CTRL2_PARAMS(16, 36, 255),
  	},
  };
  
  static int sru_s_ctrl(struct v4l2_ctrl *ctrl)
  {
  	struct vsp1_sru *sru =
  		container_of(ctrl->handler, struct vsp1_sru, ctrls);
  	const struct vsp1_sru_param *param;
  	u32 value;
  
  	switch (ctrl->id) {
  	case V4L2_CID_VSP1_SRU_INTENSITY:
  		param = &vsp1_sru_params[ctrl->val - 1];
  
  		value = vsp1_sru_read(sru, VI6_SRU_CTRL0);
  		value &= ~(VI6_SRU_CTRL0_PARAM0_MASK |
  			   VI6_SRU_CTRL0_PARAM1_MASK);
  		value |= param->ctrl0;
  		vsp1_sru_write(sru, VI6_SRU_CTRL0, value);
  
  		vsp1_sru_write(sru, VI6_SRU_CTRL2, param->ctrl2);
  		break;
  	}
  
  	return 0;
  }
  
  static const struct v4l2_ctrl_ops sru_ctrl_ops = {
  	.s_ctrl = sru_s_ctrl,
  };
  
  static const struct v4l2_ctrl_config sru_intensity_control = {
  	.ops = &sru_ctrl_ops,
  	.id = V4L2_CID_VSP1_SRU_INTENSITY,
  	.name = "Intensity",
  	.type = V4L2_CTRL_TYPE_INTEGER,
  	.min = 1,
  	.max = 6,
  	.def = 1,
  	.step = 1,
  };
  
  /* -----------------------------------------------------------------------------
   * V4L2 Subdevice Core Operations
   */
  
  static int sru_s_stream(struct v4l2_subdev *subdev, int enable)
  {
  	struct vsp1_sru *sru = to_sru(subdev);
  	struct v4l2_mbus_framefmt *input;
  	struct v4l2_mbus_framefmt *output;
  	u32 ctrl0;
  	int ret;
  
  	ret = vsp1_entity_set_streaming(&sru->entity, enable);
  	if (ret < 0)
  		return ret;
  
  	if (!enable)
  		return 0;
  
  	input = &sru->entity.formats[SRU_PAD_SINK];
  	output = &sru->entity.formats[SRU_PAD_SOURCE];
  
  	if (input->code == V4L2_MBUS_FMT_ARGB8888_1X32)
  		ctrl0 = VI6_SRU_CTRL0_PARAM2 | VI6_SRU_CTRL0_PARAM3
  		      | VI6_SRU_CTRL0_PARAM4;
  	else
  		ctrl0 = VI6_SRU_CTRL0_PARAM3;
  
  	if (input->width != output->width)
  		ctrl0 |= VI6_SRU_CTRL0_MODE_UPSCALE;
  
  	/* Take the control handler lock to ensure that the CTRL0 value won't be
  	 * changed behind our back by a set control operation.
  	 */
  	mutex_lock(sru->ctrls.lock);
  	ctrl0 |= vsp1_sru_read(sru, VI6_SRU_CTRL0)
  	       & (VI6_SRU_CTRL0_PARAM0_MASK | VI6_SRU_CTRL0_PARAM1_MASK);
  	mutex_unlock(sru->ctrls.lock);
  
  	vsp1_sru_write(sru, VI6_SRU_CTRL1, VI6_SRU_CTRL1_PARAM5);
  
  	return 0;
  }
  
  /* -----------------------------------------------------------------------------
   * V4L2 Subdevice Pad Operations
   */
  
  static int sru_enum_mbus_code(struct v4l2_subdev *subdev,
  			      struct v4l2_subdev_fh *fh,
  			      struct v4l2_subdev_mbus_code_enum *code)
  {
  	static const unsigned int codes[] = {
  		V4L2_MBUS_FMT_ARGB8888_1X32,
  		V4L2_MBUS_FMT_AYUV8_1X32,
  	};
  	struct v4l2_mbus_framefmt *format;
  
  	if (code->pad == SRU_PAD_SINK) {
  		if (code->index >= ARRAY_SIZE(codes))
  			return -EINVAL;
  
  		code->code = codes[code->index];
  	} else {
  		/* The SRU can't perform format conversion, the sink format is
  		 * always identical to the source format.
  		 */
  		if (code->index)
  			return -EINVAL;
  
  		format = v4l2_subdev_get_try_format(fh, SRU_PAD_SINK);
  		code->code = format->code;
  	}
  
  	return 0;
  }
  
  static int sru_enum_frame_size(struct v4l2_subdev *subdev,
  			       struct v4l2_subdev_fh *fh,
  			       struct v4l2_subdev_frame_size_enum *fse)
  {
  	struct v4l2_mbus_framefmt *format;
  
  	format = v4l2_subdev_get_try_format(fh, SRU_PAD_SINK);
  
  	if (fse->index || fse->code != format->code)
  		return -EINVAL;
  
  	if (fse->pad == SRU_PAD_SINK) {
  		fse->min_width = SRU_MIN_SIZE;
  		fse->max_width = SRU_MAX_SIZE;
  		fse->min_height = SRU_MIN_SIZE;
  		fse->max_height = SRU_MAX_SIZE;
  	} else {
  		fse->min_width = format->width;
  		fse->min_height = format->height;
  		if (format->width <= SRU_MAX_SIZE / 2 &&
  		    format->height <= SRU_MAX_SIZE / 2) {
  			fse->max_width = format->width * 2;
  			fse->max_height = format->height * 2;
  		} else {
  			fse->max_width = format->width;
  			fse->max_height = format->height;
  		}
  	}
  
  	return 0;
  }
  
  static int sru_get_format(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh,
  			  struct v4l2_subdev_format *fmt)
  {
  	struct vsp1_sru *sru = to_sru(subdev);
  
  	fmt->format = *vsp1_entity_get_pad_format(&sru->entity, fh, fmt->pad,
  						  fmt->which);
  
  	return 0;
  }
  
  static void sru_try_format(struct vsp1_sru *sru, struct v4l2_subdev_fh *fh,
  			   unsigned int pad, struct v4l2_mbus_framefmt *fmt,
  			   enum v4l2_subdev_format_whence which)
  {
  	struct v4l2_mbus_framefmt *format;
  	unsigned int input_area;
  	unsigned int output_area;
  
  	switch (pad) {
  	case SRU_PAD_SINK:
  		/* Default to YUV if the requested format is not supported. */
  		if (fmt->code != V4L2_MBUS_FMT_ARGB8888_1X32 &&
  		    fmt->code != V4L2_MBUS_FMT_AYUV8_1X32)
  			fmt->code = V4L2_MBUS_FMT_AYUV8_1X32;
  
  		fmt->width = clamp(fmt->width, SRU_MIN_SIZE, SRU_MAX_SIZE);
  		fmt->height = clamp(fmt->height, SRU_MIN_SIZE, SRU_MAX_SIZE);
  		break;
  
  	case SRU_PAD_SOURCE:
  		/* The SRU can't perform format conversion. */
  		format = vsp1_entity_get_pad_format(&sru->entity, fh,
  						    SRU_PAD_SINK, which);
  		fmt->code = format->code;
  
  		/* We can upscale by 2 in both direction, but not independently.
  		 * Compare the input and output rectangles areas (avoiding
  		 * integer overflows on the output): if the requested output
  		 * area is larger than 1.5^2 the input area upscale by two,
  		 * otherwise don't scale.
  		 */
  		input_area = format->width * format->height;
  		output_area = min(fmt->width, SRU_MAX_SIZE)
  			    * min(fmt->height, SRU_MAX_SIZE);
  
  		if (fmt->width <= SRU_MAX_SIZE / 2 &&
  		    fmt->height <= SRU_MAX_SIZE / 2 &&
  		    output_area > input_area * 9 / 4) {
  			fmt->width = format->width * 2;
  			fmt->height = format->height * 2;
  		} else {
  			fmt->width = format->width;
  			fmt->height = format->height;
  		}
  		break;
  	}
  
  	fmt->field = V4L2_FIELD_NONE;
  	fmt->colorspace = V4L2_COLORSPACE_SRGB;
  }
  
  static int sru_set_format(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh,
  			  struct v4l2_subdev_format *fmt)
  {
  	struct vsp1_sru *sru = to_sru(subdev);
  	struct v4l2_mbus_framefmt *format;
  
  	sru_try_format(sru, fh, fmt->pad, &fmt->format, fmt->which);
  
  	format = vsp1_entity_get_pad_format(&sru->entity, fh, fmt->pad,
  					    fmt->which);
  	*format = fmt->format;
  
  	if (fmt->pad == SRU_PAD_SINK) {
  		/* Propagate the format to the source pad. */
  		format = vsp1_entity_get_pad_format(&sru->entity, fh,
  						    SRU_PAD_SOURCE, fmt->which);
  		*format = fmt->format;
  
  		sru_try_format(sru, fh, SRU_PAD_SOURCE, format, fmt->which);
  	}
  
  	return 0;
  }
  
  /* -----------------------------------------------------------------------------
   * V4L2 Subdevice Operations
   */
  
  static struct v4l2_subdev_video_ops sru_video_ops = {
  	.s_stream = sru_s_stream,
  };
  
  static struct v4l2_subdev_pad_ops sru_pad_ops = {
  	.enum_mbus_code = sru_enum_mbus_code,
  	.enum_frame_size = sru_enum_frame_size,
  	.get_fmt = sru_get_format,
  	.set_fmt = sru_set_format,
  };
  
  static struct v4l2_subdev_ops sru_ops = {
  	.video	= &sru_video_ops,
  	.pad    = &sru_pad_ops,
  };
  
  /* -----------------------------------------------------------------------------
   * Initialization and Cleanup
   */
  
  struct vsp1_sru *vsp1_sru_create(struct vsp1_device *vsp1)
  {
  	struct v4l2_subdev *subdev;
  	struct vsp1_sru *sru;
  	int ret;
  
  	sru = devm_kzalloc(vsp1->dev, sizeof(*sru), GFP_KERNEL);
  	if (sru == NULL)
  		return ERR_PTR(-ENOMEM);
  
  	sru->entity.type = VSP1_ENTITY_SRU;
  
  	ret = vsp1_entity_init(vsp1, &sru->entity, 2);
  	if (ret < 0)
  		return ERR_PTR(ret);
  
  	/* Initialize the V4L2 subdev. */
  	subdev = &sru->entity.subdev;
  	v4l2_subdev_init(subdev, &sru_ops);
  
  	subdev->entity.ops = &vsp1_media_ops;
  	subdev->internal_ops = &vsp1_subdev_internal_ops;
  	snprintf(subdev->name, sizeof(subdev->name), "%s sru",
  		 dev_name(vsp1->dev));
  	v4l2_set_subdevdata(subdev, sru);
  	subdev->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
  
  	vsp1_entity_init_formats(subdev, NULL);
  
  	/* Initialize the control handler. */
  	v4l2_ctrl_handler_init(&sru->ctrls, 1);
  	v4l2_ctrl_new_custom(&sru->ctrls, &sru_intensity_control, NULL);
  
  	sru->entity.subdev.ctrl_handler = &sru->ctrls;
  
  	if (sru->ctrls.error) {
  		dev_err(vsp1->dev, "sru: failed to initialize controls\n");
  		ret = sru->ctrls.error;
  		vsp1_entity_destroy(&sru->entity);
  		return ERR_PTR(ret);
  	}
  
  	return sru;
  }
  