saa7134-vbi.c

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/*
 *
 * device driver for philips saa7134 based TV cards
 * video4linux video interface
 *
 * (c) 2001,02 Gerd Knorr <[email protected]> [SuSE Labs]
 *
 *  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.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

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

#include "saa7134-reg.h"
#include "saa7134.h"

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

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

static unsigned int vbibufs = 4;
module_param(vbibufs, int, 0444);
MODULE_PARM_DESC(vbibufs,"number of vbi buffers, range 2-32");

#define dprintk(fmt, arg...)    if (vbi_debug) \
    printk(KERN_DEBUG "%s/vbi: " fmt, dev->name , ## arg)

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

#define VBI_LINE_COUNT     16
#define VBI_LINE_LENGTH  2048
#define VBI_SCALE       0x200

static void task_init(struct saa7134_dev *dev, struct saa7134_buf *buf,
              int task)
{
    struct saa7134_tvnorm *norm = dev->tvnorm;

    /* setup video scaler */
    saa_writeb(SAA7134_VBI_H_START1(task), norm->h_start     &  0xff);
    saa_writeb(SAA7134_VBI_H_START2(task), norm->h_start     >> 8);
    saa_writeb(SAA7134_VBI_H_STOP1(task),  norm->h_stop      &  0xff);
    saa_writeb(SAA7134_VBI_H_STOP2(task),  norm->h_stop      >> 8);
    saa_writeb(SAA7134_VBI_V_START1(task), norm->vbi_v_start_0 &  0xff);
    saa_writeb(SAA7134_VBI_V_START2(task), norm->vbi_v_start_0 >> 8);
    saa_writeb(SAA7134_VBI_V_STOP1(task),  norm->vbi_v_stop_0  &  0xff);
    saa_writeb(SAA7134_VBI_V_STOP2(task),  norm->vbi_v_stop_0  >> 8);

    saa_writeb(SAA7134_VBI_H_SCALE_INC1(task),        VBI_SCALE & 0xff);
    saa_writeb(SAA7134_VBI_H_SCALE_INC2(task),        VBI_SCALE >> 8);
    saa_writeb(SAA7134_VBI_PHASE_OFFSET_LUMA(task),   0x00);
    saa_writeb(SAA7134_VBI_PHASE_OFFSET_CHROMA(task), 0x00);

    saa_writeb(SAA7134_VBI_H_LEN1(task), buf->vb.width   & 0xff);
    saa_writeb(SAA7134_VBI_H_LEN2(task), buf->vb.width   >> 8);
    saa_writeb(SAA7134_VBI_V_LEN1(task), buf->vb.height  & 0xff);
    saa_writeb(SAA7134_VBI_V_LEN2(task), buf->vb.height  >> 8);

    saa_andorb(SAA7134_DATA_PATH(task), 0xc0, 0x00);
}

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

static int buffer_activate(struct saa7134_dev *dev,
               struct saa7134_buf *buf,
               struct saa7134_buf *next)
{
    unsigned long control,base;

    dprintk("buffer_activate [%p]\n",buf);
    buf->vb.state = VIDEOBUF_ACTIVE;
    buf->top_seen = 0;

    task_init(dev,buf,TASK_A);
    task_init(dev,buf,TASK_B);
    saa_writeb(SAA7134_OFMT_DATA_A, 0x06);
    saa_writeb(SAA7134_OFMT_DATA_B, 0x06);

    /* DMA: setup channel 2+3 (= VBI Task A+B) */
    base    = saa7134_buffer_base(buf);
    control = SAA7134_RS_CONTROL_BURST_16 |
        SAA7134_RS_CONTROL_ME |
        (buf->pt->dma >> 12);
    saa_writel(SAA7134_RS_BA1(2),base);
    saa_writel(SAA7134_RS_BA2(2),base + buf->vb.size/2);
    saa_writel(SAA7134_RS_PITCH(2),buf->vb.width);
    saa_writel(SAA7134_RS_CONTROL(2),control);
    saa_writel(SAA7134_RS_BA1(3),base);
    saa_writel(SAA7134_RS_BA2(3),base + buf->vb.size/2);
    saa_writel(SAA7134_RS_PITCH(3),buf->vb.width);
    saa_writel(SAA7134_RS_CONTROL(3),control);

    /* start DMA */
    saa7134_set_dmabits(dev);
    mod_timer(&dev->vbi_q.timeout, jiffies+BUFFER_TIMEOUT);

    return 0;
}

static int buffer_prepare(struct videobuf_queue *q,
              struct videobuf_buffer *vb,
              enum v4l2_field field)
{
    struct saa7134_fh *fh   = q->priv_data;
    struct saa7134_dev *dev = fh->dev;
    struct saa7134_buf *buf = container_of(vb,struct saa7134_buf,vb);
    struct saa7134_tvnorm *norm = dev->tvnorm;
    unsigned int lines, llength, size;
    int err;

    lines   = norm->vbi_v_stop_0 - norm->vbi_v_start_0 +1;
    if (lines > VBI_LINE_COUNT)
        lines = VBI_LINE_COUNT;
    llength = VBI_LINE_LENGTH;
    size = lines * llength * 2;
    if (0 != buf->vb.baddr  &&  buf->vb.bsize < size)
        return -EINVAL;

    if (buf->vb.size != size)
        saa7134_dma_free(q,buf);

    if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
        struct videobuf_dmabuf *dma=videobuf_to_dma(&buf->vb);

        buf->vb.width  = llength;
        buf->vb.height = lines;
        buf->vb.size   = size;
        buf->pt        = &fh->pt_vbi;

        err = videobuf_iolock(q,&buf->vb,NULL);
        if (err)
            goto oops;
        err = saa7134_pgtable_build(dev->pci,buf->pt,
                        dma->sglist,
                        dma->sglen,
                        saa7134_buffer_startpage(buf));
        if (err)
            goto oops;
    }
    buf->vb.state = VIDEOBUF_PREPARED;
    buf->activate = buffer_activate;
    buf->vb.field = field;
    return 0;

 oops:
    saa7134_dma_free(q,buf);
    return err;
}

static int
buffer_setup(struct videobuf_queue *q, unsigned int *count, unsigned int *size)
{
    struct saa7134_fh *fh   = q->priv_data;
    struct saa7134_dev *dev = fh->dev;
    int llength,lines;

    lines   = dev->tvnorm->vbi_v_stop_0 - dev->tvnorm->vbi_v_start_0 +1;
    llength = VBI_LINE_LENGTH;
    *size = lines * llength * 2;
    if (0 == *count)
        *count = vbibufs;
    *count = saa7134_buffer_count(*size,*count);
    return 0;
}

static void buffer_queue(struct videobuf_queue *q, struct videobuf_buffer *vb)
{
    struct saa7134_fh *fh = q->priv_data;
    struct saa7134_dev *dev = fh->dev;
    struct saa7134_buf *buf = container_of(vb,struct saa7134_buf,vb);

    saa7134_buffer_queue(dev,&dev->vbi_q,buf);
}

static void buffer_release(struct videobuf_queue *q, struct videobuf_buffer *vb)
{
    struct saa7134_buf *buf = container_of(vb,struct saa7134_buf,vb);

    saa7134_dma_free(q,buf);
}

struct videobuf_queue_ops saa7134_vbi_qops = {
    .buf_setup    = buffer_setup,
    .buf_prepare  = buffer_prepare,
    .buf_queue    = buffer_queue,
    .buf_release  = buffer_release,
};

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

int saa7134_vbi_init1(struct saa7134_dev *dev)
{
    INIT_LIST_HEAD(&dev->vbi_q.queue);
    init_timer(&dev->vbi_q.timeout);
    dev->vbi_q.timeout.function = saa7134_buffer_timeout;
    dev->vbi_q.timeout.data     = (unsigned long)(&dev->vbi_q);
    dev->vbi_q.dev              = dev;

    if (vbibufs < 2)
        vbibufs = 2;
    if (vbibufs > VIDEO_MAX_FRAME)
        vbibufs = VIDEO_MAX_FRAME;
    return 0;
}

int saa7134_vbi_fini(struct saa7134_dev *dev)
{
    /* nothing */
    return 0;
}

void saa7134_irq_vbi_done(struct saa7134_dev *dev, unsigned long status)
{
    spin_lock(&dev->slock);
    if (dev->vbi_q.curr) {
        dev->vbi_fieldcount++;
        /* make sure we have seen both fields */
        if ((status & 0x10) == 0x00) {
            dev->vbi_q.curr->top_seen = 1;
            goto done;
        }
        if (!dev->vbi_q.curr->top_seen)
            goto done;

        dev->vbi_q.curr->vb.field_count = dev->vbi_fieldcount;
        saa7134_buffer_finish(dev,&dev->vbi_q,VIDEOBUF_DONE);
    }
    saa7134_buffer_next(dev,&dev->vbi_q);

 done:
    spin_unlock(&dev->slock);
}

/* ----------------------------------------------------------- */
/*
 * Local variables:
 * c-basic-offset: 8
 * End:
 */