// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2018 BayLibre, SAS
 * Author: Maxime Jourdan <mjourdan@baylibre.com>
 */

#include <linux/of.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/mfd/syscon.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/kthread.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-mem2mem.h>
#include <media/v4l2-dev.h>
#include <media/videobuf2-dma-contig.h>

#include "vdec.h"
#include "esparser.h"
#include "vdec_helpers.h"

struct dummy_buf {
        struct vb2_v4l2_buffer vb;
        struct list_head list;
};

/* 16 MiB for parsed bitstream swap exchange */
#define SIZE_VIFIFO SZ_16M

static u32 get_output_size(u32 width, u32 height)
{
        return ALIGN(width * height, SZ_64K);
}

u32 amvdec_get_output_size(struct amvdec_session *sess)
{
        return get_output_size(sess->width, sess->height);
}
EXPORT_SYMBOL_GPL(amvdec_get_output_size);

static int vdec_codec_needs_recycle(struct amvdec_session *sess)
{
        struct amvdec_codec_ops *codec_ops = sess->fmt_out->codec_ops;

        return codec_ops->can_recycle && codec_ops->recycle;
}

static int vdec_recycle_thread(void *data)
{
        struct amvdec_session *sess = data;
        struct amvdec_core *core = sess->core;
        struct amvdec_codec_ops *codec_ops = sess->fmt_out->codec_ops;
        struct amvdec_buffer *tmp, *n;

        while (!kthread_should_stop()) {
                mutex_lock(&sess->bufs_recycle_lock);
                list_for_each_entry_safe(tmp, n, &sess->bufs_recycle, list) {
                        if (!codec_ops->can_recycle(core))
                                break;

                        codec_ops->recycle(core, tmp->vb->index);
                        list_del(&tmp->list);
                        kfree(tmp);
                }
                mutex_unlock(&sess->bufs_recycle_lock);

                usleep_range(5000, 10000);
        }

        return 0;
}

static int vdec_poweron(struct amvdec_session *sess)
{
        int ret;
        struct amvdec_ops *vdec_ops = sess->fmt_out->vdec_ops;

        ret = clk_prepare_enable(sess->core->dos_parser_clk);
        if (ret)
                return ret;

        ret = clk_prepare_enable(sess->core->dos_clk);
        if (ret)
                goto disable_dos_parser;

        ret = vdec_ops->start(sess);
        if (ret)
                goto disable_dos;

        esparser_power_up(sess);

        return 0;

disable_dos:
        clk_disable_unprepare(sess->core->dos_clk);
disable_dos_parser:
        clk_disable_unprepare(sess->core->dos_parser_clk);

        return ret;
}

static void vdec_wait_inactive(struct amvdec_session *sess)
{
        /* We consider 50ms with no IRQ to be inactive. */
        while (time_is_after_jiffies64(sess->last_irq_jiffies +
                                       msecs_to_jiffies(50)))
                msleep(25);
}

static void vdec_poweroff(struct amvdec_session *sess)
{
        struct amvdec_ops *vdec_ops = sess->fmt_out->vdec_ops;
        struct amvdec_codec_ops *codec_ops = sess->fmt_out->codec_ops;

        sess->should_stop = 1;
        vdec_wait_inactive(sess);
        if (codec_ops->drain)
                codec_ops->drain(sess);

        vdec_ops->stop(sess);
        clk_disable_unprepare(sess->core->dos_clk);
        clk_disable_unprepare(sess->core->dos_parser_clk);
}

static void
vdec_queue_recycle(struct amvdec_session *sess, struct vb2_buffer *vb)
{
        struct amvdec_buffer *new_buf;

        new_buf = kmalloc_obj(*new_buf);
        if (!new_buf)
                return;
        new_buf->vb = vb;

        mutex_lock(&sess->bufs_recycle_lock);
        list_add_tail(&new_buf->list, &sess->bufs_recycle);
        mutex_unlock(&sess->bufs_recycle_lock);
}

static void vdec_m2m_device_run(void *priv)
{
        struct amvdec_session *sess = priv;

        schedule_work(&sess->esparser_queue_work);
}

static void vdec_m2m_job_abort(void *priv)
{
        struct amvdec_session *sess = priv;

        v4l2_m2m_job_finish(sess->m2m_dev, sess->m2m_ctx);
}

static const struct v4l2_m2m_ops vdec_m2m_ops = {
        .device_run = vdec_m2m_device_run,
        .job_abort = vdec_m2m_job_abort,
};

static void process_num_buffers(struct vb2_queue *q,
                                struct amvdec_session *sess,
                                unsigned int *num_buffers,
                                bool is_reqbufs)
{
        const struct amvdec_format *fmt_out = sess->fmt_out;
        unsigned int q_num_bufs = vb2_get_num_buffers(q);
        unsigned int buffers_total = q_num_bufs + *num_buffers;
        u32 min_buf_capture = v4l2_ctrl_g_ctrl(sess->ctrl_min_buf_capture);

        if (q_num_bufs + *num_buffers < min_buf_capture)
                *num_buffers = min_buf_capture - q_num_bufs;
        if (is_reqbufs && buffers_total < fmt_out->min_buffers)
                *num_buffers = fmt_out->min_buffers - q_num_bufs;
        if (buffers_total > fmt_out->max_buffers)
                *num_buffers = fmt_out->max_buffers - q_num_bufs;

        /* We need to program the complete CAPTURE buffer list
         * in registers during start_streaming, and the firmwares
         * are free to choose any of them to write frames to. As such,
         * we need all of them to be queued into the driver
         */
        sess->num_dst_bufs = q_num_bufs + *num_buffers;
        q->min_queued_buffers = max(fmt_out->min_buffers, sess->num_dst_bufs);
}

static int vdec_queue_setup(struct vb2_queue *q, unsigned int *num_buffers,
                            unsigned int *num_planes, unsigned int sizes[],
                            struct device *alloc_devs[])
{
        struct amvdec_session *sess = vb2_get_drv_priv(q);
        u32 output_size = amvdec_get_output_size(sess);

        if (*num_planes) {
                switch (q->type) {
                case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
                        if (*num_planes != 1 ||
                            sizes[0] < sess->src_buffer_size)
                                return -EINVAL;
                        break;
                case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
                        switch (sess->pixfmt_cap) {
                        case V4L2_PIX_FMT_NV12M:
                                if (*num_planes != 2 ||
                                    sizes[0] < output_size ||
                                    sizes[1] < output_size / 2)
                                        return -EINVAL;
                                break;
                        case V4L2_PIX_FMT_YUV420M:
                                if (*num_planes != 3 ||
                                    sizes[0] < output_size ||
                                    sizes[1] < output_size / 4 ||
                                    sizes[2] < output_size / 4)
                                        return -EINVAL;
                                break;
                        default:
                                return -EINVAL;
                        }

                        process_num_buffers(q, sess, num_buffers, false);
                        break;
                }

                return 0;
        }

        switch (q->type) {
        case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
                sizes[0] = sess->src_buffer_size;
                *num_planes = 1;
                break;
        case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
                switch (sess->pixfmt_cap) {
                case V4L2_PIX_FMT_NV12M:
                        sizes[0] = output_size;
                        sizes[1] = output_size / 2;
                        *num_planes = 2;
                        break;
                case V4L2_PIX_FMT_YUV420M:
                        sizes[0] = output_size;
                        sizes[1] = output_size / 4;
                        sizes[2] = output_size / 4;
                        *num_planes = 3;
                        break;
                default:
                        return -EINVAL;
                }

                process_num_buffers(q, sess, num_buffers, true);
                break;
        default:
                return -EINVAL;
        }

        sess->changed_format = 1;
        return 0;
}

static void vdec_vb2_buf_queue(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
        struct amvdec_session *sess = vb2_get_drv_priv(vb->vb2_queue);
        struct v4l2_m2m_ctx *m2m_ctx = sess->m2m_ctx;

        v4l2_m2m_buf_queue(m2m_ctx, vbuf);

        if (!sess->streamon_out)
                return;

        if (sess->streamon_cap &&
            vb->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE &&
            vdec_codec_needs_recycle(sess))
                vdec_queue_recycle(sess, vb);

        schedule_work(&sess->esparser_queue_work);
}

static int vdec_start_streaming(struct vb2_queue *q, unsigned int count)
{
        struct amvdec_session *sess = vb2_get_drv_priv(q);
        struct amvdec_codec_ops *codec_ops = sess->fmt_out->codec_ops;
        struct amvdec_core *core = sess->core;
        struct vb2_v4l2_buffer *buf;
        int ret;

        if (core->cur_sess && core->cur_sess != sess) {
                ret = -EBUSY;
                goto bufs_done;
        }

        if (q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
                sess->streamon_out = 1;
        else
                sess->streamon_cap = 1;

        if (!sess->streamon_out)
                return 0;

        if (sess->status == STATUS_NEEDS_RESUME &&
            q->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE &&
            sess->changed_format) {
                codec_ops->resume(sess);
                sess->status = STATUS_RUNNING;
                return 0;
        }

        if (sess->status == STATUS_RUNNING ||
            sess->status == STATUS_NEEDS_RESUME ||
            sess->status == STATUS_INIT)
                return 0;

        sess->vififo_size = SIZE_VIFIFO;
        sess->vififo_vaddr =
                dma_alloc_coherent(sess->core->dev, sess->vififo_size,
                                   &sess->vififo_paddr, GFP_KERNEL);
        if (!sess->vififo_vaddr) {
                dev_err(sess->core->dev, "Failed to request VIFIFO buffer\n");
                ret = -ENOMEM;
                goto bufs_done;
        }

        sess->should_stop = 0;
        sess->keyframe_found = 0;
        sess->last_offset = 0;
        sess->wrap_count = 0;
        sess->pixelaspect.numerator = 1;
        sess->pixelaspect.denominator = 1;
        atomic_set(&sess->esparser_queued_bufs, 0);
        v4l2_ctrl_s_ctrl(sess->ctrl_min_buf_capture, 1);

        ret = vdec_poweron(sess);
        if (ret)
                goto vififo_free;

        sess->sequence_cap = 0;
        sess->sequence_out = 0;
        if (vdec_codec_needs_recycle(sess))
                sess->recycle_thread = kthread_run(vdec_recycle_thread, sess,
                                                   "vdec_recycle");

        sess->status = STATUS_INIT;
        core->cur_sess = sess;
        schedule_work(&sess->esparser_queue_work);
        return 0;

vififo_free:
        dma_free_coherent(sess->core->dev, sess->vififo_size,
                          sess->vififo_vaddr, sess->vififo_paddr);
bufs_done:
        while ((buf = v4l2_m2m_src_buf_remove(sess->m2m_ctx)))
                v4l2_m2m_buf_done(buf, VB2_BUF_STATE_QUEUED);
        while ((buf = v4l2_m2m_dst_buf_remove(sess->m2m_ctx)))
                v4l2_m2m_buf_done(buf, VB2_BUF_STATE_QUEUED);

        if (q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
                sess->streamon_out = 0;
        else
                sess->streamon_cap = 0;

        return ret;
}

static void vdec_free_canvas(struct amvdec_session *sess)
{
        int i;

        for (i = 0; i < sess->canvas_num; ++i)
                meson_canvas_free(sess->core->canvas, sess->canvas_alloc[i]);

        sess->canvas_num = 0;
}

static void vdec_reset_timestamps(struct amvdec_session *sess)
{
        struct amvdec_timestamp *tmp, *n;

        list_for_each_entry_safe(tmp, n, &sess->timestamps, list) {
                list_del(&tmp->list);
                kfree(tmp);
        }
}

static void vdec_reset_bufs_recycle(struct amvdec_session *sess)
{
        struct amvdec_buffer *tmp, *n;

        list_for_each_entry_safe(tmp, n, &sess->bufs_recycle, list) {
                list_del(&tmp->list);
                kfree(tmp);
        }
}

static void vdec_stop_streaming(struct vb2_queue *q)
{
        struct amvdec_session *sess = vb2_get_drv_priv(q);
        struct amvdec_codec_ops *codec_ops = sess->fmt_out->codec_ops;
        struct amvdec_core *core = sess->core;
        struct vb2_v4l2_buffer *buf;

        if (sess->status == STATUS_RUNNING ||
            sess->status == STATUS_INIT ||
            (sess->status == STATUS_NEEDS_RESUME &&
             (!sess->streamon_out || !sess->streamon_cap))) {
                if (vdec_codec_needs_recycle(sess))
                        kthread_stop(sess->recycle_thread);

                vdec_poweroff(sess);
                vdec_free_canvas(sess);
                dma_free_coherent(sess->core->dev, sess->vififo_size,
                                  sess->vififo_vaddr, sess->vififo_paddr);
                vdec_reset_timestamps(sess);
                vdec_reset_bufs_recycle(sess);
                kfree(sess->priv);
                sess->priv = NULL;
                core->cur_sess = NULL;
                sess->status = STATUS_STOPPED;
        }

        if (q->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
                while ((buf = v4l2_m2m_src_buf_remove(sess->m2m_ctx)))
                        v4l2_m2m_buf_done(buf, VB2_BUF_STATE_ERROR);

                sess->streamon_out = 0;
        } else {
                /* Drain remaining refs if was still running */
                if (sess->status >= STATUS_RUNNING && codec_ops->drain)
                        codec_ops->drain(sess);

                while ((buf = v4l2_m2m_dst_buf_remove(sess->m2m_ctx)))
                        v4l2_m2m_buf_done(buf, VB2_BUF_STATE_ERROR);

                sess->streamon_cap = 0;
        }
}

static int vdec_vb2_buf_prepare(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);

        vbuf->field = V4L2_FIELD_NONE;
        return 0;
}

static const struct vb2_ops vdec_vb2_ops = {
        .queue_setup = vdec_queue_setup,
        .start_streaming = vdec_start_streaming,
        .stop_streaming = vdec_stop_streaming,
        .buf_queue = vdec_vb2_buf_queue,
        .buf_prepare = vdec_vb2_buf_prepare,
};

static int
vdec_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
{
        strscpy(cap->driver, "meson-vdec", sizeof(cap->driver));
        strscpy(cap->card, "Amlogic Video Decoder", sizeof(cap->card));
        strscpy(cap->bus_info, "platform:meson-vdec", sizeof(cap->bus_info));

        return 0;
}

static const struct amvdec_format *
find_format(const struct amvdec_format *fmts, u32 size, u32 pixfmt)
{
        unsigned int i;

        for (i = 0; i < size; i++) {
                if (fmts[i].pixfmt == pixfmt)
                        return &fmts[i];
        }

        return NULL;
}

static unsigned int
vdec_supports_pixfmt_cap(const struct amvdec_format *fmt_out, u32 pixfmt_cap)
{
        int i;

        for (i = 0; fmt_out->pixfmts_cap[i]; i++)
                if (fmt_out->pixfmts_cap[i] == pixfmt_cap)
                        return 1;

        return 0;
}

static const struct amvdec_format *
vdec_try_fmt_common(struct amvdec_session *sess, u32 size,
                    struct v4l2_format *f)
{
        struct v4l2_pix_format_mplane *pixmp = &f->fmt.pix_mp;
        struct v4l2_plane_pix_format *pfmt = pixmp->plane_fmt;
        const struct amvdec_format *fmts = sess->core->platform->formats;
        const struct amvdec_format *fmt_out = NULL;
        u32 output_size = 0;

        memset(pfmt[0].reserved, 0, sizeof(pfmt[0].reserved));
        memset(pixmp->reserved, 0, sizeof(pixmp->reserved));

        switch (f->type) {
        case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
                fmt_out = find_format(fmts, size, pixmp->pixelformat);
                if (!fmt_out) {
                        pixmp->pixelformat = V4L2_PIX_FMT_MPEG2;
                        fmt_out = find_format(fmts, size, pixmp->pixelformat);
                }
                break;
        case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
                fmt_out = sess->fmt_out;
                break;
        default:
                return NULL;
        }

        pixmp->width  = clamp(pixmp->width,  (u32)256, fmt_out->max_width);
        pixmp->height = clamp(pixmp->height, (u32)144, fmt_out->max_height);
        output_size = get_output_size(pixmp->width, pixmp->height);

        if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
                if (!pfmt[0].sizeimage)
                        pfmt[0].sizeimage = sess->src_buffer_size;
                pfmt[0].bytesperline = 0;
                pixmp->num_planes = 1;
        } else if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
                fmt_out = sess->fmt_out;
                if (!vdec_supports_pixfmt_cap(fmt_out, pixmp->pixelformat))
                        pixmp->pixelformat = fmt_out->pixfmts_cap[0];

                memset(pfmt[1].reserved, 0, sizeof(pfmt[1].reserved));
                if (pixmp->pixelformat == V4L2_PIX_FMT_NV12M) {
                        pfmt[0].sizeimage = output_size;
                        pfmt[0].bytesperline = ALIGN(pixmp->width, 32);

                        pfmt[1].sizeimage = output_size / 2;
                        pfmt[1].bytesperline = ALIGN(pixmp->width, 32);
                        pixmp->num_planes = 2;
                } else if (pixmp->pixelformat == V4L2_PIX_FMT_YUV420M) {
                        pfmt[0].sizeimage = output_size;
                        pfmt[0].bytesperline = ALIGN(pixmp->width, 32);

                        pfmt[1].sizeimage = output_size / 4;
                        pfmt[1].bytesperline = ALIGN(pixmp->width, 32) / 2;

                        pfmt[2].sizeimage = output_size / 2;
                        pfmt[2].bytesperline = ALIGN(pixmp->width, 32) / 2;
                        pixmp->num_planes = 3;
                }
        }

        if (pixmp->field == V4L2_FIELD_ANY)
                pixmp->field = V4L2_FIELD_NONE;

        return fmt_out;
}

static int vdec_try_fmt(struct file *file, void *fh, struct v4l2_format *f)
{
        struct amvdec_session *sess = file_to_amvdec_session(file);

        vdec_try_fmt_common(sess, sess->core->platform->num_formats, f);

        return 0;
}

static int vdec_g_fmt(struct file *file, void *fh, struct v4l2_format *f)
{
        struct amvdec_session *sess = file_to_amvdec_session(file);
        struct v4l2_pix_format_mplane *pixmp = &f->fmt.pix_mp;

        if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
                pixmp->pixelformat = sess->pixfmt_cap;
        else if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
                pixmp->pixelformat = sess->fmt_out->pixfmt;

        if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
                pixmp->width = sess->width;
                pixmp->height = sess->height;
                pixmp->colorspace = sess->colorspace;
                pixmp->ycbcr_enc = sess->ycbcr_enc;
                pixmp->quantization = sess->quantization;
                pixmp->xfer_func = sess->xfer_func;
        } else if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
                pixmp->width = sess->width;
                pixmp->height = sess->height;
        }

        vdec_try_fmt_common(sess, sess->core->platform->num_formats, f);

        return 0;
}

static int vdec_s_fmt(struct file *file, void *fh, struct v4l2_format *f)
{
        struct amvdec_session *sess = file_to_amvdec_session(file);
        struct v4l2_pix_format_mplane *pixmp = &f->fmt.pix_mp;
        u32 num_formats = sess->core->platform->num_formats;
        const struct amvdec_format *fmt_out;
        struct v4l2_pix_format_mplane orig_pixmp;
        struct v4l2_format format;
        u32 pixfmt_out = 0, pixfmt_cap = 0;

        orig_pixmp = *pixmp;

        fmt_out = vdec_try_fmt_common(sess, num_formats, f);
        if (!fmt_out)
                return -EINVAL;

        if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
                pixfmt_out = pixmp->pixelformat;
                pixfmt_cap = sess->pixfmt_cap;
        } else if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
                pixfmt_cap = pixmp->pixelformat;
                pixfmt_out = sess->fmt_out->pixfmt;
        }

        memset(&format, 0, sizeof(format));

        format.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
        format.fmt.pix_mp.pixelformat = pixfmt_out;
        format.fmt.pix_mp.width = orig_pixmp.width;
        format.fmt.pix_mp.height = orig_pixmp.height;
        vdec_try_fmt_common(sess, num_formats, &format);

        if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
                sess->width = format.fmt.pix_mp.width;
                sess->height = format.fmt.pix_mp.height;
                sess->colorspace = pixmp->colorspace;
                sess->ycbcr_enc = pixmp->ycbcr_enc;
                sess->quantization = pixmp->quantization;
                sess->xfer_func = pixmp->xfer_func;
                sess->src_buffer_size = pixmp->plane_fmt[0].sizeimage;
        }

        memset(&format, 0, sizeof(format));

        format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
        format.fmt.pix_mp.pixelformat = pixfmt_cap;
        format.fmt.pix_mp.width = orig_pixmp.width;
        format.fmt.pix_mp.height = orig_pixmp.height;
        vdec_try_fmt_common(sess, num_formats, &format);

        sess->width = format.fmt.pix_mp.width;
        sess->height = format.fmt.pix_mp.height;

        if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
                sess->fmt_out = fmt_out;
        else if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
                sess->pixfmt_cap = format.fmt.pix_mp.pixelformat;

        return 0;
}

static int vdec_enum_fmt(struct file *file, void *fh, struct v4l2_fmtdesc *f)
{
        struct amvdec_session *sess = file_to_amvdec_session(file);
        const struct vdec_platform *platform = sess->core->platform;
        const struct amvdec_format *fmt_out;

        memset(f->reserved, 0, sizeof(f->reserved));

        if (f->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
                if (f->index >= platform->num_formats)
                        return -EINVAL;

                fmt_out = &platform->formats[f->index];
                f->pixelformat = fmt_out->pixfmt;
                f->flags = fmt_out->flags;
        } else if (f->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
                fmt_out = sess->fmt_out;
                if (f->index >= 4 || !fmt_out->pixfmts_cap[f->index])
                        return -EINVAL;

                f->pixelformat = fmt_out->pixfmts_cap[f->index];
        } else {
                return -EINVAL;
        }

        return 0;
}

static int vdec_enum_framesizes(struct file *file, void *fh,
                                struct v4l2_frmsizeenum *fsize)
{
        struct amvdec_session *sess = file_to_amvdec_session(file);
        const struct amvdec_format *formats = sess->core->platform->formats;
        const struct amvdec_format *fmt;
        u32 num_formats = sess->core->platform->num_formats;

        fmt = find_format(formats, num_formats, fsize->pixel_format);
        if (!fmt || fsize->index)
                return -EINVAL;

        fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;

        fsize->stepwise.min_width = 256;
        fsize->stepwise.max_width = fmt->max_width;
        fsize->stepwise.step_width = 1;
        fsize->stepwise.min_height = 144;
        fsize->stepwise.max_height = fmt->max_height;
        fsize->stepwise.step_height = 1;

        return 0;
}

static int
vdec_decoder_cmd(struct file *file, void *fh, struct v4l2_decoder_cmd *cmd)
{
        struct amvdec_session *sess = file_to_amvdec_session(file);
        struct amvdec_codec_ops *codec_ops = sess->fmt_out->codec_ops;
        struct device *dev = sess->core->dev;
        int ret;

        ret = v4l2_m2m_ioctl_try_decoder_cmd(file, fh, cmd);
        if (ret)
                return ret;

        if (!(sess->streamon_out & sess->streamon_cap))
                return 0;

        if (cmd->cmd == V4L2_DEC_CMD_START) {
                v4l2_m2m_clear_state(sess->m2m_ctx);
                sess->should_stop = 0;
                return 0;
        }

        /* Should not happen */
        if (cmd->cmd != V4L2_DEC_CMD_STOP)
                return -EINVAL;

        dev_dbg(dev, "Received V4L2_DEC_CMD_STOP\n");

        sess->should_stop = 1;

        v4l2_m2m_mark_stopped(sess->m2m_ctx);

        if (codec_ops->drain) {
                vdec_wait_inactive(sess);
                codec_ops->drain(sess);
        } else if (codec_ops->eos_sequence) {
                u32 len;
                const u8 *data = codec_ops->eos_sequence(&len);

                esparser_queue_eos(sess->core, data, len);
                vdec_wait_inactive(sess);
        }

        return ret;
}

static int vdec_subscribe_event(struct v4l2_fh *fh,
                                const struct v4l2_event_subscription *sub)
{
        switch (sub->type) {
        case V4L2_EVENT_EOS:
        case V4L2_EVENT_SOURCE_CHANGE:
                return v4l2_event_subscribe(fh, sub, 0, NULL);
        case V4L2_EVENT_CTRL:
                return v4l2_ctrl_subscribe_event(fh, sub);
        default:
                return -EINVAL;
        }
}

static int vdec_g_pixelaspect(struct file *file, void *fh, int type,
                              struct v4l2_fract *f)
{
        struct amvdec_session *sess = file_to_amvdec_session(file);

        if (type != V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
                return -EINVAL;

        *f = sess->pixelaspect;
        return 0;
}

static const struct v4l2_ioctl_ops vdec_ioctl_ops = {
        .vidioc_querycap = vdec_querycap,
        .vidioc_enum_fmt_vid_cap = vdec_enum_fmt,
        .vidioc_enum_fmt_vid_out = vdec_enum_fmt,
        .vidioc_s_fmt_vid_cap_mplane = vdec_s_fmt,
        .vidioc_s_fmt_vid_out_mplane = vdec_s_fmt,
        .vidioc_g_fmt_vid_cap_mplane = vdec_g_fmt,
        .vidioc_g_fmt_vid_out_mplane = vdec_g_fmt,
        .vidioc_try_fmt_vid_cap_mplane = vdec_try_fmt,
        .vidioc_try_fmt_vid_out_mplane = vdec_try_fmt,
        .vidioc_reqbufs = v4l2_m2m_ioctl_reqbufs,
        .vidioc_querybuf = v4l2_m2m_ioctl_querybuf,
        .vidioc_prepare_buf = v4l2_m2m_ioctl_prepare_buf,
        .vidioc_qbuf = v4l2_m2m_ioctl_qbuf,
        .vidioc_expbuf = v4l2_m2m_ioctl_expbuf,
        .vidioc_dqbuf = v4l2_m2m_ioctl_dqbuf,
        .vidioc_create_bufs = v4l2_m2m_ioctl_create_bufs,
        .vidioc_streamon = v4l2_m2m_ioctl_streamon,
        .vidioc_streamoff = v4l2_m2m_ioctl_streamoff,
        .vidioc_enum_framesizes = vdec_enum_framesizes,
        .vidioc_subscribe_event = vdec_subscribe_event,
        .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
        .vidioc_try_decoder_cmd = v4l2_m2m_ioctl_try_decoder_cmd,
        .vidioc_decoder_cmd = vdec_decoder_cmd,
        .vidioc_g_pixelaspect = vdec_g_pixelaspect,
};

static int m2m_queue_init(void *priv, struct vb2_queue *src_vq,
                          struct vb2_queue *dst_vq)
{
        struct amvdec_session *sess = priv;
        int ret;

        src_vq->type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
        src_vq->io_modes = VB2_MMAP | VB2_DMABUF;
        src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
        src_vq->ops = &vdec_vb2_ops;
        src_vq->mem_ops = &vb2_dma_contig_memops;
        src_vq->drv_priv = sess;
        src_vq->buf_struct_size = sizeof(struct dummy_buf);
        src_vq->min_queued_buffers = 1;
        src_vq->dev = sess->core->dev;
        src_vq->lock = &sess->lock;
        ret = vb2_queue_init(src_vq);
        if (ret)
                return ret;

        dst_vq->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
        dst_vq->io_modes = VB2_MMAP | VB2_DMABUF;
        dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
        dst_vq->ops = &vdec_vb2_ops;
        dst_vq->mem_ops = &vb2_dma_contig_memops;
        dst_vq->drv_priv = sess;
        dst_vq->buf_struct_size = sizeof(struct dummy_buf);
        dst_vq->min_queued_buffers = 1;
        dst_vq->dev = sess->core->dev;
        dst_vq->lock = &sess->lock;
        return vb2_queue_init(dst_vq);
}

static int vdec_init_ctrls(struct amvdec_session *sess)
{
        struct v4l2_ctrl_handler *ctrl_handler = &sess->ctrl_handler;
        int ret;

        ret = v4l2_ctrl_handler_init(ctrl_handler, 1);
        if (ret)
                return ret;

        sess->ctrl_min_buf_capture =
                v4l2_ctrl_new_std(ctrl_handler, NULL,
                                  V4L2_CID_MIN_BUFFERS_FOR_CAPTURE, 1, 32, 1,
                                  1);

        ret = ctrl_handler->error;
        if (ret) {
                v4l2_ctrl_handler_free(ctrl_handler);
                return ret;
        }

        return 0;
}

static int vdec_open(struct file *file)
{
        struct amvdec_core *core = video_drvdata(file);
        struct device *dev = core->dev;
        const struct amvdec_format *formats = core->platform->formats;
        struct amvdec_session *sess;
        int ret;

        sess = kzalloc_obj(*sess);
        if (!sess)
                return -ENOMEM;

        sess->core = core;

        sess->m2m_dev = v4l2_m2m_init(&vdec_m2m_ops);
        if (IS_ERR(sess->m2m_dev)) {
                dev_err(dev, "Fail to v4l2_m2m_init\n");
                ret = PTR_ERR(sess->m2m_dev);
                goto err_free_sess;
        }

        sess->m2m_ctx = v4l2_m2m_ctx_init(sess->m2m_dev, sess, m2m_queue_init);
        if (IS_ERR(sess->m2m_ctx)) {
                dev_err(dev, "Fail to v4l2_m2m_ctx_init\n");
                ret = PTR_ERR(sess->m2m_ctx);
                goto err_m2m_release;
        }

        ret = vdec_init_ctrls(sess);
        if (ret)
                goto err_m2m_ctx_release;

        sess->pixfmt_cap = formats[0].pixfmts_cap[0];
        sess->fmt_out = &formats[0];
        sess->width = 1280;
        sess->height = 720;
        sess->pixelaspect.numerator = 1;
        sess->pixelaspect.denominator = 1;
        sess->src_buffer_size = SZ_1M;

        INIT_LIST_HEAD(&sess->timestamps);
        INIT_LIST_HEAD(&sess->bufs_recycle);
        INIT_WORK(&sess->esparser_queue_work, esparser_queue_all_src);
        mutex_init(&sess->lock);
        mutex_init(&sess->bufs_recycle_lock);
        spin_lock_init(&sess->ts_spinlock);

        v4l2_fh_init(&sess->fh, core->vdev_dec);
        sess->fh.ctrl_handler = &sess->ctrl_handler;
        v4l2_fh_add(&sess->fh, file);
        sess->fh.m2m_ctx = sess->m2m_ctx;

        return 0;

err_m2m_ctx_release:
        v4l2_m2m_ctx_release(sess->m2m_ctx);
err_m2m_release:
        v4l2_m2m_release(sess->m2m_dev);
err_free_sess:
        kfree(sess);
        return ret;
}

static int vdec_close(struct file *file)
{
        struct amvdec_session *sess = file_to_amvdec_session(file);

        v4l2_m2m_ctx_release(sess->m2m_ctx);
        v4l2_m2m_release(sess->m2m_dev);
        v4l2_fh_del(&sess->fh, file);
        v4l2_fh_exit(&sess->fh);

        mutex_destroy(&sess->lock);
        mutex_destroy(&sess->bufs_recycle_lock);

        kfree(sess);

        return 0;
}

static const struct v4l2_file_operations vdec_fops = {
        .owner = THIS_MODULE,
        .open = vdec_open,
        .release = vdec_close,
        .unlocked_ioctl = video_ioctl2,
        .poll = v4l2_m2m_fop_poll,
        .mmap = v4l2_m2m_fop_mmap,
};

static irqreturn_t vdec_isr(int irq, void *data)
{
        struct amvdec_core *core = data;
        struct amvdec_session *sess = core->cur_sess;

        sess->last_irq_jiffies = get_jiffies_64();

        return sess->fmt_out->codec_ops->isr(sess);
}

static irqreturn_t vdec_threaded_isr(int irq, void *data)
{
        struct amvdec_core *core = data;
        struct amvdec_session *sess = core->cur_sess;

        return sess->fmt_out->codec_ops->threaded_isr(sess);
}

static const struct of_device_id vdec_dt_match[] = {
        { .compatible = "amlogic,gxbb-vdec",
          .data = &vdec_platform_gxbb },
        { .compatible = "amlogic,gxm-vdec",
          .data = &vdec_platform_gxm },
        { .compatible = "amlogic,gxl-vdec",
          .data = &vdec_platform_gxl },
        { .compatible = "amlogic,gxlx-vdec",
          .data = &vdec_platform_gxlx },
        { .compatible = "amlogic,g12a-vdec",
          .data = &vdec_platform_g12a },
        { .compatible = "amlogic,sm1-vdec",
          .data = &vdec_platform_sm1 },
        {}
};
MODULE_DEVICE_TABLE(of, vdec_dt_match);

static int vdec_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct video_device *vdev;
        struct amvdec_core *core;
        const struct of_device_id *of_id;
        int irq;
        int ret;

        core = devm_kzalloc(dev, sizeof(*core), GFP_KERNEL);
        if (!core)
                return -ENOMEM;

        core->dev = dev;
        platform_set_drvdata(pdev, core);

        core->dos_base = devm_platform_ioremap_resource_byname(pdev, "dos");
        if (IS_ERR(core->dos_base))
                return PTR_ERR(core->dos_base);

        core->esparser_base = devm_platform_ioremap_resource_byname(pdev, "esparser");
        if (IS_ERR(core->esparser_base))
                return PTR_ERR(core->esparser_base);

        core->regmap_ao =
                syscon_regmap_lookup_by_phandle(dev->of_node,
                                                "amlogic,ao-sysctrl");
        if (IS_ERR(core->regmap_ao)) {
                dev_err(dev, "Couldn't regmap AO sysctrl\n");
                return PTR_ERR(core->regmap_ao);
        }

        core->canvas = meson_canvas_get(dev);
        if (IS_ERR(core->canvas))
                return PTR_ERR(core->canvas);

        of_id = of_match_node(vdec_dt_match, dev->of_node);
        core->platform = of_id->data;

        if (core->platform->revision == VDEC_REVISION_G12A ||
            core->platform->revision == VDEC_REVISION_SM1) {
                core->vdec_hevcf_clk = devm_clk_get(dev, "vdec_hevcf");
                if (IS_ERR(core->vdec_hevcf_clk))
                        return -EPROBE_DEFER;
        }

        core->dos_parser_clk = devm_clk_get(dev, "dos_parser");
        if (IS_ERR(core->dos_parser_clk))
                return -EPROBE_DEFER;

        core->dos_clk = devm_clk_get(dev, "dos");
        if (IS_ERR(core->dos_clk))
                return -EPROBE_DEFER;

        core->vdec_1_clk = devm_clk_get(dev, "vdec_1");
        if (IS_ERR(core->vdec_1_clk))
                return -EPROBE_DEFER;

        core->vdec_hevc_clk = devm_clk_get(dev, "vdec_hevc");
        if (IS_ERR(core->vdec_hevc_clk))
                return -EPROBE_DEFER;

        irq = platform_get_irq_byname(pdev, "vdec");
        if (irq < 0)
                return irq;

        ret = devm_request_threaded_irq(core->dev, irq, vdec_isr,
                                        vdec_threaded_isr, IRQF_ONESHOT,
                                        "vdec", core);
        if (ret)
                return ret;

        ret = esparser_init(pdev, core);
        if (ret)
                return ret;

        ret = v4l2_device_register(dev, &core->v4l2_dev);
        if (ret) {
                dev_err(dev, "Couldn't register v4l2 device\n");
                return -ENOMEM;
        }

        vdev = video_device_alloc();
        if (!vdev) {
                ret = -ENOMEM;
                goto err_vdev_release;
        }

        core->vdev_dec = vdev;
        core->dev_dec = dev;
        mutex_init(&core->lock);

        strscpy(vdev->name, "meson-video-decoder", sizeof(vdev->name));
        vdev->release = video_device_release;
        vdev->fops = &vdec_fops;
        vdev->ioctl_ops = &vdec_ioctl_ops;
        vdev->vfl_dir = VFL_DIR_M2M;
        vdev->v4l2_dev = &core->v4l2_dev;
        vdev->lock = &core->lock;
        vdev->device_caps = V4L2_CAP_VIDEO_M2M_MPLANE | V4L2_CAP_STREAMING;

        video_set_drvdata(vdev, core);

        ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
        if (ret) {
                dev_err(dev, "Failed registering video device\n");
                goto err_vdev_release;
        }

        return 0;

err_vdev_release:
        video_device_release(vdev);
        v4l2_device_unregister(&core->v4l2_dev);
        return ret;
}

static void vdec_remove(struct platform_device *pdev)
{
        struct amvdec_core *core = platform_get_drvdata(pdev);

        video_unregister_device(core->vdev_dec);
        v4l2_device_unregister(&core->v4l2_dev);
}

static struct platform_driver meson_vdec_driver = {
        .probe = vdec_probe,
        .remove = vdec_remove,
        .driver = {
                .name = "meson-vdec",
                .of_match_table = vdec_dt_match,
        },
};
module_platform_driver(meson_vdec_driver);

MODULE_DESCRIPTION("Meson video decoder driver for GXBB/GXL/GXM/G12/SM1");
MODULE_AUTHOR("Maxime Jourdan <mjourdan@baylibre.com>");
MODULE_LICENSE("GPL");