/*
* vsp1_uds.c -- R-Car VSP1 Up and Down Scaler
*
* Copyright (C) 2013-2014 Renesas Electronics 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_uds.h"
#define UDS_MIN_SIZE 4U
#define UDS_MAX_SIZE 8190U
#define UDS_MIN_FACTOR 0x0100
#define UDS_MAX_FACTOR 0xffff
/* -----------------------------------------------------------------------------
* Device Access
*/
static inline u32 vsp1_uds_read(struct vsp1_uds *uds, u32 reg)
{
return vsp1_read(uds->entity.vsp1,
reg + uds->entity.index * VI6_UDS_OFFSET);
}
static inline void vsp1_uds_write(struct vsp1_uds *uds, u32 reg, u32 data)
{
vsp1_write(uds->entity.vsp1,
reg + uds->entity.index * VI6_UDS_OFFSET, data);
}
/* -----------------------------------------------------------------------------
* Scaling Computation
*/
void vsp1_uds_set_alpha(struct vsp1_uds *uds, unsigned int alpha)
{
vsp1_uds_write(uds, VI6_UDS_ALPVAL, alpha << VI6_UDS_ALPVAL_VAL0_SHIFT);
}
/*
* uds_output_size - Return the output size for an input size and scaling ratio
* @input: input size in pixels
* @ratio: scaling ratio in U4.12 fixed-point format
*/
static unsigned int uds_output_size(unsigned int input, unsigned int ratio)
{
if (ratio > 4096) {
/* Down-scaling */
unsigned int mp;
mp = ratio / 4096;
mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
return (input - 1) / mp * mp * 4096 / ratio + 1;
} else {
/* Up-scaling */
return (input - 1) * 4096 / ratio + 1;
}
}
/*
* uds_output_limits - Return the min and max output sizes for an input size
* @input: input size in pixels
* @minimum: minimum output size (returned)
* @maximum: maximum output size (returned)
*/
static void uds_output_limits(unsigned int input,
unsigned int *minimum, unsigned int *maximum)
{
*minimum = max(uds_output_size(input, UDS_MAX_FACTOR), UDS_MIN_SIZE);
*maximum = min(uds_output_size(input, UDS_MIN_FACTOR), UDS_MAX_SIZE);
}
/*
* uds_passband_width - Return the passband filter width for a scaling ratio
* @ratio: scaling ratio in U4.12 fixed-point format
*/
static unsigned int uds_passband_width(unsigned int ratio)
{
if (ratio >= 4096) {
/* Down-scaling */
unsigned int mp;
mp = ratio / 4096;
mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
return 64 * 4096 * mp / ratio;
} else {
/* Up-scaling */
return 64;
}
}
static unsigned int uds_compute_ratio(unsigned int input, unsigned int output)
{
/* TODO: This is an approximation that will need to be refined. */
return (input - 1) * 4096 / (output - 1);
}
/* -----------------------------------------------------------------------------
* V4L2 Subdevice Core Operations
*/
static int uds_s_stream(struct v4l2_subdev *subdev, int enable)
{
struct vsp1_uds *uds = to_uds(subdev);
const struct v4l2_mbus_framefmt *output;
const struct v4l2_mbus_framefmt *input;
unsigned int hscale;
unsigned int vscale;
bool multitap;
if (!enable)
return 0;
input = &uds->entity.formats[UDS_PAD_SINK];
output = &uds->entity.formats[UDS_PAD_SOURCE];
hscale = uds_compute_ratio(input->width, output->width);
vscale = uds_compute_ratio(input->height, output->height);
dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
/* Multi-tap scaling can't be enabled along with alpha scaling when
* scaling down with a factor lower than or equal to 1/2 in either
* direction.
*/
if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
multitap = false;
else
multitap = true;
vsp1_uds_write(uds, VI6_UDS_CTRL,
(uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
(multitap ? VI6_UDS_CTRL_BC : 0));
vsp1_uds_write(uds, VI6_UDS_PASS_BWIDTH,
(uds_passband_width(hscale)
<< VI6_UDS_PASS_BWIDTH_H_SHIFT) |
(uds_passband_width(vscale)
<< VI6_UDS_PASS_BWIDTH_V_SHIFT));
/* Set the scaling ratios and the output size. */
vsp1_uds_write(uds, VI6_UDS_SCALE,
(hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
(vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
vsp1_uds_write(uds, VI6_UDS_CLIP_SIZE,
(output->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
(output->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
return 0;
}
/* -----------------------------------------------------------------------------
* V4L2 Subdevice Pad Operations
*/
static int uds_enum_mbus_code(struct v4l2_subdev *subdev,
struct v4l2_subdev_pad_config *cfg,
struct v4l2_subdev_mbus_code_enum *code)
{
static const unsigned int codes[] = {
MEDIA_BUS_FMT_ARGB8888_1X32,
MEDIA_BUS_FMT_AYUV8_1X32,
};
struct vsp1_uds *uds = to_uds(subdev);
if (code->pad == UDS_PAD_SINK) {
if (code->index >= ARRAY_SIZE(codes))
return -EINVAL;
code->code = codes[code->index];
} else {
struct v4l2_mbus_framefmt *format;
/* The UDS can't perform format conversion, the sink format is
* always identical to the source format.
*/
if (code->index)
return -EINVAL;
format = vsp1_entity_get_pad_format(&uds->entity, cfg,
UDS_PAD_SINK, code->which);
code->code = format->code;
}
return 0;
}
static int uds_enum_frame_size(struct v4l2_subdev *subdev,
struct v4l2_subdev_pad_config *cfg,
struct v4l2_subdev_frame_size_enum *fse)
{
struct vsp1_uds *uds = to_uds(subdev);
struct v4l2_mbus_framefmt *format;
format = vsp1_entity_get_pad_format(&uds->entity, cfg,
UDS_PAD_SINK, fse->which);
if (fse->index || fse->code != format->code)
return -EINVAL;
if (fse->pad == UDS_PAD_SINK) {
fse->min_width = UDS_MIN_SIZE;
fse->max_width = UDS_MAX_SIZE;
fse->min_height = UDS_MIN_SIZE;
fse->max_height = UDS_MAX_SIZE;
} else {
uds_output_limits(format->width, &fse->min_width,
&fse->max_width);
uds_output_limits(format->height, &fse->min_height,
&fse->max_height);
}
return 0;
}
static int uds_get_format(struct v4l2_subdev *subdev, struct v4l2_subdev_pad_config *cfg,
struct v4l2_subdev_format *fmt)
{
struct vsp1_uds *uds = to_uds(subdev);
fmt->format = *vsp1_entity_get_pad_format(&uds->entity, cfg, fmt->pad,
fmt->which);
return 0;
}
static void uds_try_format(struct vsp1_uds *uds, struct v4l2_subdev_pad_config *cfg,
unsigned int pad, struct v4l2_mbus_framefmt *fmt,
enum v4l2_subdev_format_whence which)
{
struct v4l2_mbus_framefmt *format;
unsigned int minimum;
unsigned int maximum;
switch (pad) {
case UDS_PAD_SINK:
/* Default to YUV if the requested format is not supported. */
if (fmt->code != MEDIA_BUS_FMT_ARGB8888_1X32 &&
fmt->code != MEDIA_BUS_FMT_AYUV8_1X32)
fmt->code = MEDIA_BUS_FMT_AYUV8_1X32;
fmt->width = clamp(fmt->width, UDS_MIN_SIZE, UDS_MAX_SIZE);
fmt->height = clamp(fmt->height, UDS_MIN_SIZE, UDS_MAX_SIZE);
break;
case UDS_PAD_SOURCE:
/* The UDS scales but can't perform format conversion. */
format = vsp1_entity_get_pad_format(&uds->entity, cfg,
UDS_PAD_SINK, which);
fmt->code = format->code;
uds_output_limits(format->width, &minimum, &maximum);
fmt->width = clamp(fmt->width, minimum, maximum);
uds_output_limits(format->height, &minimum, &maximum);
fmt->height = clamp(fmt->height, minimum, maximum);
break;
}
fmt->field = V4L2_FIELD_NONE;
fmt->colorspace = V4L2_COLORSPACE_SRGB;
}
static int uds_set_format(struct v4l2_subdev *subdev, struct v4l2_subdev_pad_config *cfg,
struct v4l2_subdev_format *fmt)
{
struct vsp1_uds *uds = to_uds(subdev);
struct v4l2_mbus_framefmt *format;
uds_try_format(uds, cfg, fmt->pad, &fmt->format, fmt->which);
format = vsp1_entity_get_pad_format(&uds->entity, cfg, fmt->pad,
fmt->which);
*format = fmt->format;
if (fmt->pad == UDS_PAD_SINK) {
/* Propagate the format to the source pad. */
format = vsp1_entity_get_pad_format(&uds->entity, cfg,
UDS_PAD_SOURCE, fmt->which);
*format = fmt->format;
uds_try_format(uds, cfg, UDS_PAD_SOURCE, format, fmt->which);
}
return 0;
}
/* -----------------------------------------------------------------------------
* V4L2 Subdevice Operations
*/
static struct v4l2_subdev_video_ops uds_video_ops = {
.s_stream = uds_s_stream,
};
static struct v4l2_subdev_pad_ops uds_pad_ops = {
.enum_mbus_code = uds_enum_mbus_code,
.enum_frame_size = uds_enum_frame_size,
.get_fmt = uds_get_format,
.set_fmt = uds_set_format,
};
static struct v4l2_subdev_ops uds_ops = {
.video = &uds_video_ops,
.pad = &uds_pad_ops,
};
/* -----------------------------------------------------------------------------
* Initialization and Cleanup
*/
struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index)
{
struct v4l2_subdev *subdev;
struct vsp1_uds *uds;
int ret;
uds = devm_kzalloc(vsp1->dev, sizeof(*uds), GFP_KERNEL);
if (uds == NULL)
return ERR_PTR(-ENOMEM);
uds->entity.type = VSP1_ENTITY_UDS;
uds->entity.index = index;
ret = vsp1_entity_init(vsp1, &uds->entity, 2);
if (ret < 0)
return ERR_PTR(ret);
/* Initialize the V4L2 subdev. */
subdev = &uds->entity.subdev;
v4l2_subdev_init(subdev, &uds_ops);
subdev->entity.ops = &vsp1_media_ops;
subdev->internal_ops = &vsp1_subdev_internal_ops;
snprintf(subdev->name, sizeof(subdev->name), "%s uds.%u",
dev_name(vsp1->dev), index);
v4l2_set_subdevdata(subdev, uds);
subdev->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
vsp1_entity_init_formats(subdev, NULL);
return uds;
}