root/drivers/media/platform/sunxi/sun4i-csi/sun4i_v4l2.c
// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2016 NextThing Co
 * Copyright (C) 2016-2019 Bootlin
 *
 * Author: Maxime Ripard <maxime.ripard@bootlin.com>
 */

#include <linux/device.h>
#include <linux/pm_runtime.h>

#include <media/v4l2-ioctl.h>
#include <media/v4l2-mc.h>
#include <media/videobuf2-v4l2.h>

#include "sun4i_csi.h"

#define CSI_DEFAULT_WIDTH       640
#define CSI_DEFAULT_HEIGHT      480

static const struct sun4i_csi_format sun4i_csi_formats[] = {
        /* YUV422 inputs */
        {
                .mbus           = MEDIA_BUS_FMT_YUYV8_2X8,
                .fourcc         = V4L2_PIX_FMT_YUV420M,
                .input          = CSI_INPUT_YUV,
                .output         = CSI_OUTPUT_YUV_420_PLANAR,
                .num_planes     = 3,
                .bpp            = { 8, 8, 8 },
                .hsub           = 2,
                .vsub           = 2,
        },
};

const struct sun4i_csi_format *sun4i_csi_find_format(const u32 *fourcc,
                                                     const u32 *mbus)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(sun4i_csi_formats); i++) {
                if (fourcc && *fourcc != sun4i_csi_formats[i].fourcc)
                        continue;

                if (mbus && *mbus != sun4i_csi_formats[i].mbus)
                        continue;

                return &sun4i_csi_formats[i];
        }

        return NULL;
}

static int sun4i_csi_querycap(struct file *file, void *priv,
                              struct v4l2_capability *cap)
{
        strscpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
        strscpy(cap->card, "sun4i-csi", sizeof(cap->card));

        return 0;
}

static int sun4i_csi_enum_input(struct file *file, void *priv,
                                struct v4l2_input *inp)
{
        if (inp->index != 0)
                return -EINVAL;

        inp->type = V4L2_INPUT_TYPE_CAMERA;
        strscpy(inp->name, "Camera", sizeof(inp->name));

        return 0;
}

static int sun4i_csi_g_input(struct file *file, void *fh,
                             unsigned int *i)
{
        *i = 0;

        return 0;
}

static int sun4i_csi_s_input(struct file *file, void *fh,
                             unsigned int i)
{
        if (i != 0)
                return -EINVAL;

        return 0;
}

static void _sun4i_csi_try_fmt(struct sun4i_csi *csi,
                               struct v4l2_pix_format_mplane *pix)
{
        const struct sun4i_csi_format *_fmt;
        unsigned int height, width;
        unsigned int i;

        _fmt = sun4i_csi_find_format(&pix->pixelformat, NULL);
        if (!_fmt)
                _fmt = &sun4i_csi_formats[0];

        pix->field = V4L2_FIELD_NONE;
        pix->colorspace = V4L2_COLORSPACE_SRGB;
        pix->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(pix->colorspace);
        pix->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(pix->colorspace);
        pix->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true, pix->colorspace,
                                                          pix->ycbcr_enc);

        pix->num_planes = _fmt->num_planes;
        pix->pixelformat = _fmt->fourcc;

        /* Align the width and height on the subsampling */
        width = ALIGN(pix->width, _fmt->hsub);
        height = ALIGN(pix->height, _fmt->vsub);

        /* Clamp the width and height to our capabilities */
        pix->width = clamp(width, _fmt->hsub, CSI_MAX_WIDTH);
        pix->height = clamp(height, _fmt->vsub, CSI_MAX_HEIGHT);

        for (i = 0; i < _fmt->num_planes; i++) {
                unsigned int hsub = i > 0 ? _fmt->hsub : 1;
                unsigned int vsub = i > 0 ? _fmt->vsub : 1;
                unsigned int bpl;

                bpl = pix->width / hsub * _fmt->bpp[i] / 8;
                pix->plane_fmt[i].bytesperline = bpl;
                pix->plane_fmt[i].sizeimage = bpl * pix->height / vsub;
        }
}

static int sun4i_csi_try_fmt_vid_cap(struct file *file, void *priv,
                                     struct v4l2_format *f)
{
        struct sun4i_csi *csi = video_drvdata(file);

        _sun4i_csi_try_fmt(csi, &f->fmt.pix_mp);

        return 0;
}

static int sun4i_csi_s_fmt_vid_cap(struct file *file, void *priv,
                                   struct v4l2_format *f)
{
        struct sun4i_csi *csi = video_drvdata(file);

        _sun4i_csi_try_fmt(csi, &f->fmt.pix_mp);
        csi->fmt = f->fmt.pix_mp;

        return 0;
}

static int sun4i_csi_g_fmt_vid_cap(struct file *file, void *priv,
                                   struct v4l2_format *f)
{
        struct sun4i_csi *csi = video_drvdata(file);

        f->fmt.pix_mp = csi->fmt;

        return 0;
}

static int sun4i_csi_enum_fmt_vid_cap(struct file *file, void *priv,
                                      struct v4l2_fmtdesc *f)
{
        if (f->index >= ARRAY_SIZE(sun4i_csi_formats))
                return -EINVAL;

        f->pixelformat = sun4i_csi_formats[f->index].fourcc;

        return 0;
}

static const struct v4l2_ioctl_ops sun4i_csi_ioctl_ops = {
        .vidioc_querycap                = sun4i_csi_querycap,

        .vidioc_enum_fmt_vid_cap        = sun4i_csi_enum_fmt_vid_cap,
        .vidioc_g_fmt_vid_cap_mplane    = sun4i_csi_g_fmt_vid_cap,
        .vidioc_s_fmt_vid_cap_mplane    = sun4i_csi_s_fmt_vid_cap,
        .vidioc_try_fmt_vid_cap_mplane  = sun4i_csi_try_fmt_vid_cap,

        .vidioc_enum_input              = sun4i_csi_enum_input,
        .vidioc_g_input                 = sun4i_csi_g_input,
        .vidioc_s_input                 = sun4i_csi_s_input,

        .vidioc_reqbufs                 = vb2_ioctl_reqbufs,
        .vidioc_create_bufs             = vb2_ioctl_create_bufs,
        .vidioc_querybuf                = vb2_ioctl_querybuf,
        .vidioc_qbuf                    = vb2_ioctl_qbuf,
        .vidioc_dqbuf                   = vb2_ioctl_dqbuf,
        .vidioc_expbuf                  = vb2_ioctl_expbuf,
        .vidioc_prepare_buf             = vb2_ioctl_prepare_buf,
        .vidioc_streamon                = vb2_ioctl_streamon,
        .vidioc_streamoff               = vb2_ioctl_streamoff,
};

static int sun4i_csi_open(struct file *file)
{
        struct sun4i_csi *csi = video_drvdata(file);
        int ret;

        ret = mutex_lock_interruptible(&csi->lock);
        if (ret)
                return ret;

        ret = pm_runtime_resume_and_get(csi->dev);
        if (ret < 0)
                goto err_unlock;

        ret = v4l2_pipeline_pm_get(&csi->vdev.entity);
        if (ret)
                goto err_pm_put;

        ret = v4l2_fh_open(file);
        if (ret)
                goto err_pipeline_pm_put;

        mutex_unlock(&csi->lock);

        return 0;

err_pipeline_pm_put:
        v4l2_pipeline_pm_put(&csi->vdev.entity);

err_pm_put:
        pm_runtime_put(csi->dev);

err_unlock:
        mutex_unlock(&csi->lock);

        return ret;
}

static int sun4i_csi_release(struct file *file)
{
        struct sun4i_csi *csi = video_drvdata(file);

        mutex_lock(&csi->lock);

        _vb2_fop_release(file, NULL);

        v4l2_pipeline_pm_put(&csi->vdev.entity);
        pm_runtime_put(csi->dev);

        mutex_unlock(&csi->lock);

        return 0;
}

static const struct v4l2_file_operations sun4i_csi_fops = {
        .owner          = THIS_MODULE,
        .open           = sun4i_csi_open,
        .release        = sun4i_csi_release,
        .unlocked_ioctl = video_ioctl2,
        .poll           = vb2_fop_poll,
        .mmap           = vb2_fop_mmap,
};

static const struct v4l2_mbus_framefmt sun4i_csi_pad_fmt_default = {
        .width = CSI_DEFAULT_WIDTH,
        .height = CSI_DEFAULT_HEIGHT,
        .code = MEDIA_BUS_FMT_YUYV8_2X8,
        .field = V4L2_FIELD_NONE,
        .colorspace = V4L2_COLORSPACE_RAW,
        .ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT,
        .quantization = V4L2_QUANTIZATION_DEFAULT,
        .xfer_func = V4L2_XFER_FUNC_DEFAULT,
};

static int sun4i_csi_subdev_init_state(struct v4l2_subdev *subdev,
                                       struct v4l2_subdev_state *sd_state)
{
        struct v4l2_mbus_framefmt *fmt;

        fmt = v4l2_subdev_state_get_format(sd_state, CSI_SUBDEV_SINK);
        *fmt = sun4i_csi_pad_fmt_default;

        return 0;
}

static int sun4i_csi_subdev_get_fmt(struct v4l2_subdev *subdev,
                                    struct v4l2_subdev_state *sd_state,
                                    struct v4l2_subdev_format *fmt)
{
        struct sun4i_csi *csi = container_of(subdev, struct sun4i_csi, subdev);
        struct v4l2_mbus_framefmt *subdev_fmt;

        if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
                subdev_fmt = v4l2_subdev_state_get_format(sd_state, fmt->pad);
        else
                subdev_fmt = &csi->subdev_fmt;

        fmt->format = *subdev_fmt;

        return 0;
}

static int sun4i_csi_subdev_set_fmt(struct v4l2_subdev *subdev,
                                    struct v4l2_subdev_state *sd_state,
                                    struct v4l2_subdev_format *fmt)
{
        struct sun4i_csi *csi = container_of(subdev, struct sun4i_csi, subdev);
        struct v4l2_mbus_framefmt *subdev_fmt;

        if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
                subdev_fmt = v4l2_subdev_state_get_format(sd_state, fmt->pad);
        else
                subdev_fmt = &csi->subdev_fmt;

        /* We can only set the format on the sink pad */
        if (fmt->pad == CSI_SUBDEV_SINK) {
                /* It's the sink, only allow changing the frame size */
                subdev_fmt->width = fmt->format.width;
                subdev_fmt->height = fmt->format.height;
                subdev_fmt->code = fmt->format.code;
        }

        fmt->format = *subdev_fmt;

        return 0;
}

static int
sun4i_csi_subdev_enum_mbus_code(struct v4l2_subdev *subdev,
                                struct v4l2_subdev_state *sd_state,
                                struct v4l2_subdev_mbus_code_enum *mbus)
{
        if (mbus->index >= ARRAY_SIZE(sun4i_csi_formats))
                return -EINVAL;

        mbus->code = sun4i_csi_formats[mbus->index].mbus;

        return 0;
}

static const struct v4l2_subdev_pad_ops sun4i_csi_subdev_pad_ops = {
        .link_validate  = v4l2_subdev_link_validate_default,
        .get_fmt        = sun4i_csi_subdev_get_fmt,
        .set_fmt        = sun4i_csi_subdev_set_fmt,
        .enum_mbus_code = sun4i_csi_subdev_enum_mbus_code,
};

const struct v4l2_subdev_ops sun4i_csi_subdev_ops = {
        .pad = &sun4i_csi_subdev_pad_ops,
};

const struct v4l2_subdev_internal_ops sun4i_csi_subdev_internal_ops = {
        .init_state     = sun4i_csi_subdev_init_state,
};

int sun4i_csi_v4l2_register(struct sun4i_csi *csi)
{
        struct video_device *vdev = &csi->vdev;
        int ret;

        vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_STREAMING;
        vdev->v4l2_dev = &csi->v4l;
        vdev->queue = &csi->queue;
        strscpy(vdev->name, KBUILD_MODNAME, sizeof(vdev->name));
        vdev->release = video_device_release_empty;
        vdev->lock = &csi->lock;

        /* Set a default format */
        csi->fmt.pixelformat = sun4i_csi_formats[0].fourcc;
        csi->fmt.width = CSI_DEFAULT_WIDTH;
        csi->fmt.height = CSI_DEFAULT_HEIGHT;
        _sun4i_csi_try_fmt(csi, &csi->fmt);
        csi->subdev_fmt = sun4i_csi_pad_fmt_default;

        vdev->fops = &sun4i_csi_fops;
        vdev->ioctl_ops = &sun4i_csi_ioctl_ops;
        video_set_drvdata(vdev, csi);

        ret = video_register_device(&csi->vdev, VFL_TYPE_VIDEO, -1);
        if (ret)
                return ret;

        dev_info(csi->dev, "Device registered as %s\n",
                 video_device_node_name(vdev));

        return 0;
}