root/drivers/staging/media/starfive/camss/stf-video.c
// SPDX-License-Identifier: GPL-2.0
/*
 * stf_video.c
 *
 * StarFive Camera Subsystem - V4L2 device node
 *
 * Copyright (C) 2021-2023 StarFive Technology Co., Ltd.
 */

#include <linux/pm_runtime.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-event.h>
#include <media/v4l2-mc.h>
#include <media/videobuf2-dma-contig.h>

#include "stf-camss.h"
#include "stf-video.h"

/* -----------------------------------------------------------------------------
 * Helper functions
 */

static inline struct stfcamss_buffer *
to_stfcamss_buffer(struct vb2_v4l2_buffer *vbuf)
{
        return container_of(vbuf, struct stfcamss_buffer, vb);
}

static const struct stfcamss_format_info *
video_g_fi_by_index(struct stfcamss_video *video, int index)
{
        if (index >= video->nformats)
                return NULL;

        return &video->formats[index];
}

static const struct stfcamss_format_info *
video_g_fi_by_mcode(struct stfcamss_video *video, u32 mcode)
{
        unsigned int i;

        for (i = 0; i < video->nformats; i++) {
                if (video->formats[i].code == mcode)
                        return &video->formats[i];
        }

        return NULL;
}

static const struct stfcamss_format_info *
video_g_fi_by_pfmt(struct stfcamss_video *video, u32 pixelformat)
{
        unsigned int i;

        for (i = 0; i < video->nformats; i++) {
                if (video->formats[i].pixelformat == pixelformat)
                        return &video->formats[i];
        }

        return NULL;
}

static int __video_try_fmt(struct stfcamss_video *video, struct v4l2_format *f)
{
        struct v4l2_pix_format *pix = &f->fmt.pix;
        const struct stfcamss_format_info *fi;
        u32 width, height;
        u32 bpl;
        unsigned int i;

        fi = video_g_fi_by_pfmt(video, pix->pixelformat);
        if (!fi)
                fi = &video->formats[0]; /* default format */

        width = pix->width;
        height = pix->height;

        memset(pix, 0, sizeof(*pix));

        pix->pixelformat = fi->pixelformat;
        pix->width = clamp_t(u32, width, STFCAMSS_FRAME_MIN_WIDTH,
                             STFCAMSS_FRAME_MAX_WIDTH);
        pix->height = clamp_t(u32, height, STFCAMSS_FRAME_MIN_HEIGHT,
                              STFCAMSS_FRAME_MAX_HEIGHT);
        bpl = pix->width * fi->bpp / 8;
        bpl = ALIGN(bpl, video->bpl_alignment);
        pix->bytesperline = bpl;

        for (i = 0; i < fi->planes; ++i)
                pix->sizeimage += bpl * pix->height / fi->vsub[i];

        pix->field = V4L2_FIELD_NONE;
        pix->colorspace = V4L2_COLORSPACE_SRGB;
        pix->flags = 0;
        pix->ycbcr_enc =
                V4L2_MAP_YCBCR_ENC_DEFAULT(pix->colorspace);
        pix->quantization = V4L2_MAP_QUANTIZATION_DEFAULT(true,
                                                          pix->colorspace,
                                                          pix->ycbcr_enc);
        pix->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(pix->colorspace);

        return 0;
}

static int stf_video_init_format(struct stfcamss_video *video)
{
        int ret;
        struct v4l2_format format = {
                .type = video->type,
                .fmt.pix = {
                        .width = 1920,
                        .height = 1080,
                        .pixelformat = V4L2_PIX_FMT_NV12,
                },
        };

        ret = __video_try_fmt(video, &format);

        if (ret < 0)
                return ret;

        video->active_fmt = format;

        return 0;
}

/* -----------------------------------------------------------------------------
 * 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 stfcamss_video *video = vb2_get_drv_priv(q);
        const struct v4l2_pix_format *format = &video->active_fmt.fmt.pix;

        if (*num_planes) {
                if (*num_planes != 1)
                        return -EINVAL;

                if (sizes[0] < format->sizeimage)
                        return -EINVAL;
        } else {
                *num_planes = 1;
                sizes[0] = format->sizeimage;
        }

        if (!sizes[0]) {
                dev_dbg(video->stfcamss->dev,
                        "%s: error size is zero.\n", __func__);
                return -EINVAL;
        }

        dev_dbg(video->stfcamss->dev, "planes = %d, size = %d\n",
                *num_planes, sizes[0]);

        return 0;
}

static int video_buf_init(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
        struct stfcamss_video *video = vb2_get_drv_priv(vb->vb2_queue);
        struct stfcamss_buffer *buffer = to_stfcamss_buffer(vbuf);
        const struct v4l2_pix_format *fmt = &video->active_fmt.fmt.pix;
        dma_addr_t *paddr;

        paddr = vb2_plane_cookie(vb, 0);
        buffer->addr[0] = *paddr;

        if (fmt->pixelformat == V4L2_PIX_FMT_NV12)
                buffer->addr[1] =
                        buffer->addr[0] + fmt->bytesperline * fmt->height;

        return 0;
}

static int video_buf_prepare(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
        struct stfcamss_video *video = vb2_get_drv_priv(vb->vb2_queue);
        const struct v4l2_pix_format *fmt = &video->active_fmt.fmt.pix;

        if (fmt->sizeimage > vb2_plane_size(vb, 0)) {
                dev_dbg(video->stfcamss->dev,
                        "sizeimage = %u, plane size = %u\n",
                        fmt->sizeimage, (unsigned int)vb2_plane_size(vb, 0));
                return -EINVAL;
        }
        vb2_set_plane_payload(vb, 0, fmt->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 stfcamss_video *video = vb2_get_drv_priv(vb->vb2_queue);
        struct stfcamss_buffer *buffer = to_stfcamss_buffer(vbuf);

        video->ops->queue_buffer(video, buffer);
}

static int video_get_subdev_format(struct stfcamss_video *video,
                                   struct v4l2_subdev_format *fmt)
{
        struct v4l2_subdev *subdev;
        struct media_pad *pad;
        struct media_entity *entity;
        int ret;

        entity = &video->vdev.entity;
        while (1) {
                pad = &entity->pads[0];
                if (!(pad->flags & MEDIA_PAD_FL_SINK))
                        break;

                pad = media_pad_remote_pad_first(pad);
                if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
                        break;

                entity = pad->entity;
                subdev = media_entity_to_v4l2_subdev(entity);

                fmt->pad = pad->index;

                ret = v4l2_subdev_call_state_active(subdev, pad, get_fmt, fmt);
                if (ret < 0 && ret != -ENOIOCTLCMD)
                        return ret;
                else if (!ret)
                        break;
        }

        return 0;
}

static int stf_video_check_format(struct stfcamss_video *video)
{
        struct v4l2_pix_format *pix = &video->active_fmt.fmt.pix;
        const struct stfcamss_format_info *fi;
        int ret;
        struct v4l2_subdev_format sd_fmt = {
                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
        };

        ret = video_get_subdev_format(video, &sd_fmt);
        if (ret < 0)
                return ret;

        fi = video_g_fi_by_mcode(video, sd_fmt.format.code);
        if (!fi)
                return -EINVAL;

        if (pix->pixelformat != fi->pixelformat ||
            pix->height != sd_fmt.format.height ||
            pix->width != sd_fmt.format.width ||
            pix->field != sd_fmt.format.field)
                return -EPIPE;

        return 0;
}

static int video_start_streaming(struct vb2_queue *q, unsigned int count)
{
        struct stfcamss_video *video = vb2_get_drv_priv(q);
        struct video_device *vdev = &video->vdev;
        int ret;

        ret = video_device_pipeline_start(vdev, &video->stfcamss->pipe);
        if (ret < 0) {
                dev_err(video->stfcamss->dev,
                        "Failed to media_pipeline_start: %d\n", ret);
                goto err_ret_buffers;
        }

        ret = pm_runtime_resume_and_get(video->stfcamss->dev);
        if (ret < 0) {
                dev_err(video->stfcamss->dev, "power up failed %d\n", ret);
                goto err_pipeline_stop;
        }

        video->ops->start_streaming(video);

        ret = v4l2_subdev_call(video->source_subdev, video, s_stream, true);
        if (ret) {
                dev_err(video->stfcamss->dev, "stream on failed\n");
                goto err_pm_put;
        }

        return 0;

err_pm_put:
        pm_runtime_put(video->stfcamss->dev);
err_pipeline_stop:
        video_device_pipeline_stop(vdev);
err_ret_buffers:
        video->ops->flush_buffers(video, VB2_BUF_STATE_QUEUED);
        return ret;
}

static void video_stop_streaming(struct vb2_queue *q)
{
        struct stfcamss_video *video = vb2_get_drv_priv(q);
        struct video_device *vdev = &video->vdev;

        video->ops->stop_streaming(video);

        v4l2_subdev_call(video->source_subdev, video, s_stream, false);

        pm_runtime_put(video->stfcamss->dev);

        video_device_pipeline_stop(vdev);
        video->ops->flush_buffers(video, VB2_BUF_STATE_ERROR);
}

static const struct vb2_ops stf_video_vb2_q_ops = {
        .queue_setup     = video_queue_setup,
        .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)
{
        strscpy(cap->driver, "starfive-camss", sizeof(cap->driver));
        strscpy(cap->card, "Starfive Camera Subsystem", sizeof(cap->card));

        return 0;
}

static int video_enum_fmt(struct file *file, void *fh, struct v4l2_fmtdesc *f)
{
        struct stfcamss_video *video = video_drvdata(file);
        const struct stfcamss_format_info *fi;

        if (f->index >= video->nformats)
                return -EINVAL;

        if (f->mbus_code) {
                /* Each entry in formats[] table has unique mbus_code */
                if (f->index > 0)
                        return -EINVAL;

                fi = video_g_fi_by_mcode(video, f->mbus_code);
        } else {
                fi = video_g_fi_by_index(video, f->index);
        }

        if (!fi)
                return -EINVAL;

        f->pixelformat = fi->pixelformat;

        return 0;
}

static int video_enum_framesizes(struct file *file, void *fh,
                                 struct v4l2_frmsizeenum *fsize)
{
        struct stfcamss_video *video = video_drvdata(file);
        unsigned int i;

        if (fsize->index)
                return -EINVAL;

        for (i = 0; i < video->nformats; i++) {
                if (video->formats[i].pixelformat == fsize->pixel_format)
                        break;
        }

        if (i == video->nformats)
                return -EINVAL;

        fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
        fsize->stepwise.min_width = STFCAMSS_FRAME_MIN_WIDTH;
        fsize->stepwise.max_width = STFCAMSS_FRAME_MAX_WIDTH;
        fsize->stepwise.min_height = STFCAMSS_FRAME_MIN_HEIGHT;
        fsize->stepwise.max_height = STFCAMSS_FRAME_MAX_HEIGHT;
        fsize->stepwise.step_width = 1;
        fsize->stepwise.step_height = 1;

        return 0;
}

static int video_g_fmt(struct file *file, void *fh, struct v4l2_format *f)
{
        struct stfcamss_video *video = video_drvdata(file);

        *f = video->active_fmt;

        return 0;
}

static int video_s_fmt(struct file *file, void *fh, struct v4l2_format *f)
{
        struct stfcamss_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_try_fmt(struct file *file, void *fh, struct v4l2_format *f)
{
        struct stfcamss_video *video = video_drvdata(file);

        return __video_try_fmt(video, f);
}

static const struct v4l2_ioctl_ops stf_vid_ioctl_ops = {
        .vidioc_querycap                = video_querycap,
        .vidioc_enum_fmt_vid_cap        = video_enum_fmt,
        .vidioc_enum_framesizes         = video_enum_framesizes,
        .vidioc_g_fmt_vid_cap           = video_g_fmt,
        .vidioc_s_fmt_vid_cap           = video_s_fmt,
        .vidioc_try_fmt_vid_cap         = 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,
};

/* -----------------------------------------------------------------------------
 * V4L2 file operations
 */

static const struct v4l2_file_operations stf_vid_fops = {
        .owner          = THIS_MODULE,
        .unlocked_ioctl = video_ioctl2,
        .open           = v4l2_fh_open,
        .release        = vb2_fop_release,
        .poll           = vb2_fop_poll,
        .mmap           = vb2_fop_mmap,
        .read           = vb2_fop_read,
};

/* -----------------------------------------------------------------------------
 * STFCAMSS video core
 */

static int stf_link_validate(struct media_link *link)
{
        struct video_device *vdev =
                media_entity_to_video_device(link->sink->entity);
        struct stfcamss_video *video = video_get_drvdata(vdev);
        int ret;

        ret = stf_video_check_format(video);

        return ret;
}

static const struct media_entity_operations stf_media_ops = {
        .link_validate = stf_link_validate,
};

static void stf_video_release(struct video_device *vdev)
{
        struct stfcamss_video *video = video_get_drvdata(vdev);

        media_entity_cleanup(&vdev->entity);

        mutex_destroy(&video->q_lock);
        mutex_destroy(&video->lock);
}

int stf_video_register(struct stfcamss_video *video,
                       struct v4l2_device *v4l2_dev, const char *name)
{
        struct video_device *vdev = &video->vdev;
        struct vb2_queue *q;
        struct media_pad *pad = &video->pad;
        int ret;

        mutex_init(&video->q_lock);
        mutex_init(&video->lock);

        q = &video->vb2_q;
        q->drv_priv = video;
        q->mem_ops = &vb2_dma_contig_memops;
        q->ops = &stf_video_vb2_q_ops;
        q->type = video->type;
        q->io_modes = VB2_DMABUF | VB2_MMAP;
        q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
        q->buf_struct_size = sizeof(struct stfcamss_buffer);
        q->dev = video->stfcamss->dev;
        q->lock = &video->q_lock;
        q->min_queued_buffers = STFCAMSS_MIN_BUFFERS;
        ret = vb2_queue_init(q);
        if (ret < 0) {
                dev_err(video->stfcamss->dev,
                        "Failed to init vb2 queue: %d\n", ret);
                goto err_mutex_destroy;
        }

        pad->flags = MEDIA_PAD_FL_SINK;
        ret = media_entity_pads_init(&vdev->entity, 1, pad);
        if (ret < 0) {
                dev_err(video->stfcamss->dev,
                        "Failed to init video entity: %d\n", ret);
                goto err_mutex_destroy;
        }

        ret = stf_video_init_format(video);
        if (ret < 0) {
                dev_err(video->stfcamss->dev,
                        "Failed to init format: %d\n", ret);
                goto err_media_cleanup;
        }

        vdev->fops = &stf_vid_fops;
        vdev->ioctl_ops = &stf_vid_ioctl_ops;
        vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
        vdev->entity.ops = &stf_media_ops;
        vdev->vfl_dir = VFL_DIR_RX;
        vdev->release = stf_video_release;
        vdev->v4l2_dev = v4l2_dev;
        vdev->queue = &video->vb2_q;
        vdev->lock = &video->lock;
        strscpy(vdev->name, name, sizeof(vdev->name));

        video_set_drvdata(vdev, video);

        ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
        if (ret < 0) {
                dev_err(video->stfcamss->dev,
                        "Failed to register video device: %d\n", ret);
                goto err_media_cleanup;
        }

        return 0;

err_media_cleanup:
        media_entity_cleanup(&vdev->entity);
err_mutex_destroy:
        mutex_destroy(&video->lock);
        mutex_destroy(&video->q_lock);
        return ret;
}

void stf_video_unregister(struct stfcamss_video *video)
{
        vb2_video_unregister_device(&video->vdev);
}