// SPDX-License-Identifier: GPL-2.0
/*
 */

#include "cx88.h"

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>

static unsigned int vbi_debug;
module_param(vbi_debug, int, 0644);
MODULE_PARM_DESC(vbi_debug, "enable debug messages [vbi]");

#define dprintk(level, fmt, arg...) do {                        \
        if (vbi_debug >= level)                                 \
                printk(KERN_DEBUG pr_fmt("%s: vbi:" fmt),       \
                        __func__, ##arg);                       \
} while (0)

/* ------------------------------------------------------------------ */

int cx8800_vbi_fmt(struct file *file, void *priv,
                   struct v4l2_format *f)
{
        struct cx8800_dev *dev = video_drvdata(file);

        f->fmt.vbi.samples_per_line = VBI_LINE_LENGTH;
        f->fmt.vbi.sample_format = V4L2_PIX_FMT_GREY;
        f->fmt.vbi.offset = 244;

        if (dev->core->tvnorm & V4L2_STD_525_60) {
                /* ntsc */
                f->fmt.vbi.sampling_rate = 28636363;
                f->fmt.vbi.start[0] = 10;
                f->fmt.vbi.start[1] = 273;
                f->fmt.vbi.count[0] = VBI_LINE_NTSC_COUNT;
                f->fmt.vbi.count[1] = VBI_LINE_NTSC_COUNT;

        } else if (dev->core->tvnorm & V4L2_STD_625_50) {
                /* pal */
                f->fmt.vbi.sampling_rate = 35468950;
                f->fmt.vbi.start[0] = V4L2_VBI_ITU_625_F1_START + 5;
                f->fmt.vbi.start[1] = V4L2_VBI_ITU_625_F2_START + 5;
                f->fmt.vbi.count[0] = VBI_LINE_PAL_COUNT;
                f->fmt.vbi.count[1] = VBI_LINE_PAL_COUNT;
        }
        return 0;
}

static int cx8800_start_vbi_dma(struct cx8800_dev    *dev,
                                struct cx88_dmaqueue *q,
                                struct cx88_buffer   *buf)
{
        struct cx88_core *core = dev->core;

        /* setup fifo + format */
        cx88_sram_channel_setup(dev->core, &cx88_sram_channels[SRAM_CH24],
                                VBI_LINE_LENGTH, buf->risc.dma);

        cx_write(MO_VBOS_CONTROL, (1 << 18) |  /* comb filter delay fixup */
                                  (1 << 15) |  /* enable vbi capture */
                                  (1 << 11));

        /* reset counter */
        cx_write(MO_VBI_GPCNTRL, GP_COUNT_CONTROL_RESET);
        q->count = 0;

        /* enable irqs */
        cx_set(MO_PCI_INTMSK, core->pci_irqmask | PCI_INT_VIDINT);
        cx_set(MO_VID_INTMSK, 0x0f0088);

        /* enable capture */
        cx_set(VID_CAPTURE_CONTROL, 0x18);

        /* start dma */
        cx_set(MO_DEV_CNTRL2, (1 << 5));
        cx_set(MO_VID_DMACNTRL, 0x88);

        return 0;
}

void cx8800_stop_vbi_dma(struct cx8800_dev *dev)
{
        struct cx88_core *core = dev->core;

        /* stop dma */
        cx_clear(MO_VID_DMACNTRL, 0x88);

        /* disable capture */
        cx_clear(VID_CAPTURE_CONTROL, 0x18);

        /* disable irqs */
        cx_clear(MO_PCI_INTMSK, PCI_INT_VIDINT);
        cx_clear(MO_VID_INTMSK, 0x0f0088);
}

int cx8800_restart_vbi_queue(struct cx8800_dev    *dev,
                             struct cx88_dmaqueue *q)
{
        struct cx88_buffer *buf;

        if (list_empty(&q->active))
                return 0;

        buf = list_entry(q->active.next, struct cx88_buffer, list);
        dprintk(2, "restart_queue [%p/%d]: restart dma\n",
                buf, buf->vb.vb2_buf.index);
        cx8800_start_vbi_dma(dev, q, buf);
        return 0;
}

/* ------------------------------------------------------------------ */

static int queue_setup(struct vb2_queue *q,
                       unsigned int *num_buffers, unsigned int *num_planes,
                       unsigned int sizes[], struct device *alloc_devs[])
{
        struct cx8800_dev *dev = q->drv_priv;

        *num_planes = 1;
        if (dev->core->tvnorm & V4L2_STD_525_60)
                sizes[0] = VBI_LINE_NTSC_COUNT * VBI_LINE_LENGTH * 2;
        else
                sizes[0] = VBI_LINE_PAL_COUNT * VBI_LINE_LENGTH * 2;
        return 0;
}

static int buffer_prepare(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
        struct cx8800_dev *dev = vb->vb2_queue->drv_priv;
        struct cx88_buffer *buf = container_of(vbuf, struct cx88_buffer, vb);
        struct sg_table *sgt = vb2_dma_sg_plane_desc(vb, 0);
        unsigned int lines;
        unsigned int size;

        if (dev->core->tvnorm & V4L2_STD_525_60)
                lines = VBI_LINE_NTSC_COUNT;
        else
                lines = VBI_LINE_PAL_COUNT;
        size = lines * VBI_LINE_LENGTH * 2;
        if (vb2_plane_size(vb, 0) < size)
                return -EINVAL;
        vb2_set_plane_payload(vb, 0, size);

        cx88_risc_buffer(dev->pci, &buf->risc, sgt->sgl,
                         0, VBI_LINE_LENGTH * lines,
                         VBI_LINE_LENGTH, 0,
                         lines);
        return 0;
}

static void buffer_finish(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
        struct cx8800_dev *dev = vb->vb2_queue->drv_priv;
        struct cx88_buffer *buf = container_of(vbuf, struct cx88_buffer, vb);
        struct cx88_riscmem *risc = &buf->risc;

        if (risc->cpu)
                dma_free_coherent(&dev->pci->dev, risc->size, risc->cpu,
                                  risc->dma);
        memset(risc, 0, sizeof(*risc));
}

static void buffer_queue(struct vb2_buffer *vb)
{
        struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
        struct cx8800_dev *dev = vb->vb2_queue->drv_priv;
        struct cx88_buffer    *buf = container_of(vbuf, struct cx88_buffer, vb);
        struct cx88_buffer    *prev;
        struct cx88_dmaqueue  *q    = &dev->vbiq;

        /* add jump to start */
        buf->risc.cpu[1] = cpu_to_le32(buf->risc.dma + 8);
        buf->risc.jmp[0] = cpu_to_le32(RISC_JUMP | RISC_CNT_INC);
        buf->risc.jmp[1] = cpu_to_le32(buf->risc.dma + 8);

        if (list_empty(&q->active)) {
                list_add_tail(&buf->list, &q->active);
                dprintk(2, "[%p/%d] vbi_queue - first active\n",
                        buf, buf->vb.vb2_buf.index);

        } else {
                buf->risc.cpu[0] |= cpu_to_le32(RISC_IRQ1);
                prev = list_entry(q->active.prev, struct cx88_buffer, list);
                list_add_tail(&buf->list, &q->active);
                prev->risc.jmp[1] = cpu_to_le32(buf->risc.dma);
                dprintk(2, "[%p/%d] buffer_queue - append to active\n",
                        buf, buf->vb.vb2_buf.index);
        }
}

static int start_streaming(struct vb2_queue *q, unsigned int count)
{
        struct cx8800_dev *dev = q->drv_priv;
        struct cx88_dmaqueue *dmaq = &dev->vbiq;
        struct cx88_buffer *buf = list_entry(dmaq->active.next,
                        struct cx88_buffer, list);

        cx8800_start_vbi_dma(dev, dmaq, buf);
        return 0;
}

static void stop_streaming(struct vb2_queue *q)
{
        struct cx8800_dev *dev = q->drv_priv;
        struct cx88_core *core = dev->core;
        struct cx88_dmaqueue *dmaq = &dev->vbiq;
        unsigned long flags;

        cx_clear(MO_VID_DMACNTRL, 0x11);
        cx_clear(VID_CAPTURE_CONTROL, 0x06);
        cx8800_stop_vbi_dma(dev);
        spin_lock_irqsave(&dev->slock, flags);
        while (!list_empty(&dmaq->active)) {
                struct cx88_buffer *buf = list_entry(dmaq->active.next,
                        struct cx88_buffer, list);

                list_del(&buf->list);
                vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
        }
        spin_unlock_irqrestore(&dev->slock, flags);
}

const struct vb2_ops cx8800_vbi_qops = {
        .queue_setup    = queue_setup,
        .buf_prepare  = buffer_prepare,
        .buf_finish = buffer_finish,
        .buf_queue    = buffer_queue,
        .wait_prepare = vb2_ops_wait_prepare,
        .wait_finish = vb2_ops_wait_finish,
        .start_streaming = start_streaming,
        .stop_streaming = stop_streaming,
};