1 files changed, 701 insertions, 0 deletions

diff --git a/drivers/media/video/cx231xx/cx231xx-vbi.c b/drivers/media/video/cx231xx/cx231xx-vbi.c
new file mode 100644
index 000000000000..94180526909c
--- /dev/null
+++ b/drivers/media/video/cx231xx/cx231xx-vbi.c
@@ -0,0 +1,701 @@
+/*
+   cx231xx_vbi.c - driver for Conexant Cx23100/101/102 USB video capture devices
+
+   Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
+        Based on cx88 driver
+
+   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 <linux/bitmap.h>
+#include <linux/usb.h>
+#include <linux/i2c.h>
+#include <linux/version.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-chip-ident.h>
+#include <media/msp3400.h>
+#include <media/tuner.h>
+
+#include "cx231xx.h"
+#include "cx231xx-vbi.h"
+
+static inline void print_err_status(struct cx231xx *dev, int packet, int status)
+{
+        char *errmsg = "Unknown";
+
+        switch (status) {
+        case -ENOENT:
+                errmsg = "unlinked synchronuously";
+                break;
+        case -ECONNRESET:
+                errmsg = "unlinked asynchronuously";
+                break;
+        case -ENOSR:
+                errmsg = "Buffer error (overrun)";
+                break;
+        case -EPIPE:
+                errmsg = "Stalled (device not responding)";
+                break;
+        case -EOVERFLOW:
+                errmsg = "Babble (bad cable?)";
+                break;
+        case -EPROTO:
+                errmsg = "Bit-stuff error (bad cable?)";
+                break;
+        case -EILSEQ:
+                errmsg = "CRC/Timeout (could be anything)";
+                break;
+        case -ETIME:
+                errmsg = "Device does not respond";
+                break;
+        }
+        if (packet < 0) {
+                cx231xx_err(DRIVER_NAME "URB status %d [%s].\n", status,
+                            errmsg);
+        } else {
+                cx231xx_err(DRIVER_NAME "URB packet %d, status %d [%s].\n",
+                            packet, status, errmsg);
+        }
+}
+
+/*
+ * Controls the isoc copy of each urb packet
+ */
+static inline int cx231xx_isoc_vbi_copy(struct cx231xx *dev, struct urb *urb)
+{
+        struct cx231xx_buffer *buf;
+        struct cx231xx_dmaqueue *dma_q = urb->context;
+        int rc = 1;
+        unsigned char *p_buffer;
+        u32 bytes_parsed = 0, buffer_size = 0;
+        u8 sav_eav = 0;
+
+        if (!dev)
+                return 0;
+
+        if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
+                return 0;
+
+        if (urb->status < 0) {
+                print_err_status(dev, -1, urb->status);
+                if (urb->status == -ENOENT)
+                        return 0;
+        }
+
+        buf = dev->vbi_mode.isoc_ctl.buf;
+
+        /* get buffer pointer and length */
+        p_buffer = urb->transfer_buffer;
+        buffer_size = urb->actual_length;
+
+        if (buffer_size > 0) {
+                bytes_parsed = 0;
+
+                if (dma_q->is_partial_line) {
+                        /* Handle the case where we were working on a partial
+                           line */
+                        sav_eav = dma_q->last_sav;
+                } else {
+                        /* Check for a SAV/EAV overlapping the
+                           buffer boundary */
+
+                        sav_eav = cx231xx_find_boundary_SAV_EAV(p_buffer,
+                                                          dma_q->partial_buf,
+                                                          &bytes_parsed);
+                }
+
+                sav_eav &= 0xF0;
+                /* Get the first line if we have some portion of an SAV/EAV from
+                   the last buffer or a partial line */
+                if (sav_eav) {
+                        bytes_parsed += cx231xx_get_vbi_line(dev, dma_q,
+                                sav_eav,                       /* SAV/EAV */
+                                p_buffer + bytes_parsed,       /* p_buffer */
+                                buffer_size - bytes_parsed);   /* buffer size */
+                }
+
+                /* Now parse data that is completely in this buffer */
+                dma_q->is_partial_line = 0;
+
+                while (bytes_parsed < buffer_size) {
+                        u32 bytes_used = 0;
+
+                        sav_eav = cx231xx_find_next_SAV_EAV(
+                                p_buffer + bytes_parsed,        /* p_buffer */
+                                buffer_size - bytes_parsed, /* buffer size */
+                                &bytes_used);   /* bytes used to get SAV/EAV */
+
+                        bytes_parsed += bytes_used;
+
+                        sav_eav &= 0xF0;
+                        if (sav_eav && (bytes_parsed < buffer_size)) {
+                                bytes_parsed += cx231xx_get_vbi_line(dev,
+                                        dma_q, sav_eav, /* SAV/EAV */
+                                        p_buffer+bytes_parsed, /* p_buffer */
+                                        buffer_size-bytes_parsed);/*buf size*/
+                        }
+                }
+
+                /* Save the last four bytes of the buffer so we can
+                check the buffer boundary condition next time */
+                memcpy(dma_q->partial_buf, p_buffer + buffer_size - 4, 4);
+                bytes_parsed = 0;
+        }
+
+        return rc;
+}
+
+/* ------------------------------------------------------------------
+        Vbi buf operations
+   ------------------------------------------------------------------*/
+
+static int
+vbi_buffer_setup(struct videobuf_queue *vq, unsigned int *count,
+                 unsigned int *size)
+{
+        struct cx231xx_fh *fh = vq->priv_data;
+        struct cx231xx *dev = fh->dev;
+        u32 height = 0;
+
+        height = ((dev->norm & V4L2_STD_625_50) ?
+                  PAL_VBI_LINES : NTSC_VBI_LINES);
+
+        *size = (dev->width * height * 2);
+        if (0 == *count)
+                *count = CX231XX_DEF_VBI_BUF;
+
+        if (*count < CX231XX_MIN_BUF)
+                *count = CX231XX_MIN_BUF;
+
+        return 0;
+}
+
+/* This is called *without* dev->slock held; please keep it that way */
+static void free_buffer(struct videobuf_queue *vq, struct cx231xx_buffer *buf)
+{
+        struct cx231xx_fh *fh = vq->priv_data;
+        struct cx231xx *dev = fh->dev;
+        unsigned long flags = 0;
+        if (in_interrupt())
+                BUG();
+
+        /* We used to wait for the buffer to finish here, but this didn't work
+           because, as we were keeping the state as VIDEOBUF_QUEUED,
+           videobuf_queue_cancel marked it as finished for us.
+           (Also, it could wedge forever if the hardware was misconfigured.)
+
+           This should be safe; by the time we get here, the buffer isn't
+           queued anymore. If we ever start marking the buffers as
+           VIDEOBUF_ACTIVE, it won't be, though.
+         */
+        spin_lock_irqsave(&dev->vbi_mode.slock, flags);
+        if (dev->vbi_mode.isoc_ctl.buf == buf)
+                dev->vbi_mode.isoc_ctl.buf = NULL;
+        spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
+
+        videobuf_vmalloc_free(&buf->vb);
+        buf->vb.state = VIDEOBUF_NEEDS_INIT;
+}
+
+static int
+vbi_buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
+                   enum v4l2_field field)
+{
+        struct cx231xx_fh *fh = vq->priv_data;
+        struct cx231xx_buffer *buf =
+            container_of(vb, struct cx231xx_buffer, vb);
+        struct cx231xx *dev = fh->dev;
+        int rc = 0, urb_init = 0;
+        u32 height = 0;
+
+        height = ((dev->norm & V4L2_STD_625_50) ?
+                  PAL_VBI_LINES : NTSC_VBI_LINES);
+        buf->vb.size = ((dev->width << 1) * height);
+
+        if (0 != buf->vb.baddr && buf->vb.bsize < buf->vb.size)
+                return -EINVAL;
+
+        buf->vb.width = dev->width;
+        buf->vb.height = height;
+        buf->vb.field = field;
+        buf->vb.field = V4L2_FIELD_SEQ_TB;
+
+        if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
+                rc = videobuf_iolock(vq, &buf->vb, NULL);
+                if (rc < 0)
+                        goto fail;
+        }
+
+        if (!dev->vbi_mode.isoc_ctl.num_bufs)
+                urb_init = 1;
+
+        if (urb_init) {
+                rc = cx231xx_init_vbi_isoc(dev, CX231XX_NUM_VBI_PACKETS,
+                                           CX231XX_NUM_VBI_BUFS,
+                                           dev->vbi_mode.alt_max_pkt_size[0],
+                                           cx231xx_isoc_vbi_copy);
+                if (rc < 0)
+                        goto fail;
+        }
+
+        buf->vb.state = VIDEOBUF_PREPARED;
+        return 0;
+
+fail:
+        free_buffer(vq, buf);
+        return rc;
+}
+
+static void
+vbi_buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
+{
+        struct cx231xx_buffer *buf =
+            container_of(vb, struct cx231xx_buffer, vb);
+        struct cx231xx_fh *fh = vq->priv_data;
+        struct cx231xx *dev = fh->dev;
+        struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
+
+        buf->vb.state = VIDEOBUF_QUEUED;
+        list_add_tail(&buf->vb.queue, &vidq->active);
+
+}
+
+static void vbi_buffer_release(struct videobuf_queue *vq,
+                               struct videobuf_buffer *vb)
+{
+        struct cx231xx_buffer *buf =
+            container_of(vb, struct cx231xx_buffer, vb);
+
+
+        free_buffer(vq, buf);
+}
+
+struct videobuf_queue_ops cx231xx_vbi_qops = {
+        .buf_setup   = vbi_buffer_setup,
+        .buf_prepare = vbi_buffer_prepare,
+        .buf_queue   = vbi_buffer_queue,
+        .buf_release = vbi_buffer_release,
+};
+
+/* ------------------------------------------------------------------
+        URB control
+   ------------------------------------------------------------------*/
+
+/*
+ * IRQ callback, called by URB callback
+ */
+static void cx231xx_irq_vbi_callback(struct urb *urb)
+{
+        struct cx231xx_dmaqueue *dma_q = urb->context;
+        struct cx231xx_video_mode *vmode =
+            container_of(dma_q, struct cx231xx_video_mode, vidq);
+        struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
+        int rc;
+
+        switch (urb->status) {
+        case 0:         /* success */
+        case -ETIMEDOUT:        /* NAK */
+                break;
+        case -ECONNRESET:       /* kill */
+        case -ENOENT:
+        case -ESHUTDOWN:
+                return;
+        default:                /* error */
+                cx231xx_err(DRIVER_NAME "urb completition error %d.\n",
+                            urb->status);
+                break;
+        }
+
+        /* Copy data from URB */
+        spin_lock(&dev->vbi_mode.slock);
+        rc = dev->vbi_mode.isoc_ctl.isoc_copy(dev, urb);
+        spin_unlock(&dev->vbi_mode.slock);
+
+        /* Reset status */
+        urb->status = 0;
+
+        urb->status = usb_submit_urb(urb, GFP_ATOMIC);
+        if (urb->status) {
+                cx231xx_err(DRIVER_NAME "urb resubmit failed (error=%i)\n",
+                            urb->status);
+        }
+}
+
+/*
+ * Stop and Deallocate URBs
+ */
+void cx231xx_uninit_vbi_isoc(struct cx231xx *dev)
+{
+        struct urb *urb;
+        int i;
+
+        cx231xx_info(DRIVER_NAME "cx231xx: called cx231xx_uninit_vbi_isoc\n");
+
+        dev->vbi_mode.isoc_ctl.nfields = -1;
+        for (i = 0; i < dev->vbi_mode.isoc_ctl.num_bufs; i++) {
+                urb = dev->vbi_mode.isoc_ctl.urb[i];
+                if (urb) {
+                        if (!irqs_disabled())
+                                usb_kill_urb(urb);
+                        else
+                                usb_unlink_urb(urb);
+
+                        if (dev->vbi_mode.isoc_ctl.transfer_buffer[i]) {
+
+                                kfree(dev->vbi_mode.isoc_ctl.
+                                      transfer_buffer[i]);
+                                dev->vbi_mode.isoc_ctl.transfer_buffer[i] =
+                                    NULL;
+                        }
+                        usb_free_urb(urb);
+                        dev->vbi_mode.isoc_ctl.urb[i] = NULL;
+                }
+                dev->vbi_mode.isoc_ctl.transfer_buffer[i] = NULL;
+        }
+
+        kfree(dev->vbi_mode.isoc_ctl.urb);
+        kfree(dev->vbi_mode.isoc_ctl.transfer_buffer);
+
+        dev->vbi_mode.isoc_ctl.urb = NULL;
+        dev->vbi_mode.isoc_ctl.transfer_buffer = NULL;
+        dev->vbi_mode.isoc_ctl.num_bufs = 0;
+
+        cx231xx_capture_start(dev, 0, Vbi);
+}
+EXPORT_SYMBOL_GPL(cx231xx_uninit_vbi_isoc);
+
+/*
+ * Allocate URBs and start IRQ
+ */
+int cx231xx_init_vbi_isoc(struct cx231xx *dev, int max_packets,
+                          int num_bufs, int max_pkt_size,
+                          int (*isoc_copy) (struct cx231xx *dev,
+                                            struct urb *urb))
+{
+        struct cx231xx_dmaqueue *dma_q = &dev->vbi_mode.vidq;
+        int i;
+        int sb_size, pipe;
+        struct urb *urb;
+        int rc;
+
+        cx231xx_info(DRIVER_NAME "cx231xx: called cx231xx_prepare_isoc\n");
+
+        /* De-allocates all pending stuff */
+        cx231xx_uninit_vbi_isoc(dev);
+
+        /* clear if any halt */
+        usb_clear_halt(dev->udev,
+                       usb_rcvbulkpipe(dev->udev,
+                                       dev->vbi_mode.end_point_addr));
+
+        dev->vbi_mode.isoc_ctl.isoc_copy = isoc_copy;
+        dev->vbi_mode.isoc_ctl.num_bufs = num_bufs;
+        dma_q->pos = 0;
+        dma_q->is_partial_line = 0;
+        dma_q->last_sav = 0;
+        dma_q->current_field = -1;
+        dma_q->bytes_left_in_line = dev->width << 1;
+        dma_q->lines_per_field = ((dev->norm & V4L2_STD_625_50) ?
+                                  PAL_VBI_LINES : NTSC_VBI_LINES);
+        dma_q->lines_completed = 0;
+        for (i = 0; i < 8; i++)
+                dma_q->partial_buf[i] = 0;
+
+        dev->vbi_mode.isoc_ctl.urb = kzalloc(sizeof(void *) * num_bufs,
+                                             GFP_KERNEL);
+        if (!dev->vbi_mode.isoc_ctl.urb) {
+                cx231xx_errdev("cannot alloc memory for usb buffers\n");
+                return -ENOMEM;
+        }
+
+        dev->vbi_mode.isoc_ctl.transfer_buffer =
+            kzalloc(sizeof(void *) * num_bufs, GFP_KERNEL);
+        if (!dev->vbi_mode.isoc_ctl.transfer_buffer) {
+                cx231xx_errdev("cannot allocate memory for usbtransfer\n");
+                kfree(dev->vbi_mode.isoc_ctl.urb);
+                return -ENOMEM;
+        }
+
+        dev->vbi_mode.isoc_ctl.max_pkt_size = max_pkt_size;
+        dev->vbi_mode.isoc_ctl.buf = NULL;
+
+        sb_size = max_packets * dev->vbi_mode.isoc_ctl.max_pkt_size;
+
+        /* allocate urbs and transfer buffers */
+        for (i = 0; i < dev->vbi_mode.isoc_ctl.num_bufs; i++) {
+
+                urb = usb_alloc_urb(0, GFP_KERNEL);
+                if (!urb) {
+                        cx231xx_err(DRIVER_NAME
+                                    ": cannot alloc isoc_ctl.urb %i\n", i);
+                        cx231xx_uninit_vbi_isoc(dev);
+                        return -ENOMEM;
+                }
+                dev->vbi_mode.isoc_ctl.urb[i] = urb;
+                urb->transfer_flags = 0;
+
+                dev->vbi_mode.isoc_ctl.transfer_buffer[i] =
+                    kzalloc(sb_size, GFP_KERNEL);
+                if (!dev->vbi_mode.isoc_ctl.transfer_buffer[i]) {
+                        cx231xx_err(DRIVER_NAME
+                                    ": unable to allocate %i bytes for transfer"
+                                    " buffer %i%s\n", sb_size, i,
+                                    in_interrupt() ? " while in int" : "");
+                        cx231xx_uninit_vbi_isoc(dev);
+                        return -ENOMEM;
+                }
+
+                pipe = usb_rcvbulkpipe(dev->udev, dev->vbi_mode.end_point_addr);
+                usb_fill_bulk_urb(urb, dev->udev, pipe,
+                                  dev->vbi_mode.isoc_ctl.transfer_buffer[i],
+                                  sb_size, cx231xx_irq_vbi_callback, dma_q);
+        }
+
+        init_waitqueue_head(&dma_q->wq);
+
+        /* submit urbs and enables IRQ */
+        for (i = 0; i < dev->vbi_mode.isoc_ctl.num_bufs; i++) {
+                rc = usb_submit_urb(dev->vbi_mode.isoc_ctl.urb[i], GFP_ATOMIC);
+                if (rc) {
+                        cx231xx_err(DRIVER_NAME
+                                    ": submit of urb %i failed (error=%i)\n", i,
+                                    rc);
+                        cx231xx_uninit_vbi_isoc(dev);
+                        return rc;
+                }
+        }
+
+        cx231xx_capture_start(dev, 1, Vbi);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(cx231xx_init_vbi_isoc);
+
+u32 cx231xx_get_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
+                         u8 sav_eav, u8 *p_buffer, u32 buffer_size)
+{
+        u32 bytes_copied = 0;
+        int current_field = -1;
+
+        switch (sav_eav) {
+
+        case SAV_VBI_FIELD1:
+                current_field = 1;
+                break;
+
+        case SAV_VBI_FIELD2:
+                current_field = 2;
+                break;
+        default:
+                break;
+        }
+
+        if (current_field < 0)
+                return bytes_copied;
+
+        dma_q->last_sav = sav_eav;
+
+        bytes_copied =
+            cx231xx_copy_vbi_line(dev, dma_q, p_buffer, buffer_size,
+                                  current_field);
+
+        return bytes_copied;
+}
+
+/*
+ * Announces that a buffer were filled and request the next
+ */
+static inline void vbi_buffer_filled(struct cx231xx *dev,
+                                     struct cx231xx_dmaqueue *dma_q,
+                                     struct cx231xx_buffer *buf)
+{
+        /* Advice that buffer was filled */
+        /* cx231xx_info(DRIVER_NAME "[%p/%d] wakeup\n", buf, buf->vb.i); */
+
+        buf->vb.state = VIDEOBUF_DONE;
+        buf->vb.field_count++;
+        do_gettimeofday(&buf->vb.ts);
+
+        dev->vbi_mode.isoc_ctl.buf = NULL;
+
+        list_del(&buf->vb.queue);
+        wake_up(&buf->vb.done);
+}
+
+u32 cx231xx_copy_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
+                          u8 *p_line, u32 length, int field_number)
+{
+        u32 bytes_to_copy;
+        struct cx231xx_buffer *buf;
+        u32 _line_size = dev->width * 2;
+
+        if (dma_q->current_field != field_number)
+                cx231xx_reset_vbi_buffer(dev, dma_q);
+
+        /* get the buffer pointer */
+        buf = dev->vbi_mode.isoc_ctl.buf;
+
+        /* Remember the field number for next time */
+        dma_q->current_field = field_number;
+
+        bytes_to_copy = dma_q->bytes_left_in_line;
+        if (bytes_to_copy > length)
+                bytes_to_copy = length;
+
+        if (dma_q->lines_completed >= dma_q->lines_per_field) {
+                dma_q->bytes_left_in_line -= bytes_to_copy;
+                dma_q->is_partial_line =
+                    (dma_q->bytes_left_in_line == 0) ? 0 : 1;
+                return 0;
+        }
+
+        dma_q->is_partial_line = 1;
+
+        /* If we don't have a buffer, just return the number of bytes we would
+           have copied if we had a buffer. */
+        if (!buf) {
+                dma_q->bytes_left_in_line -= bytes_to_copy;
+                dma_q->is_partial_line =
+                    (dma_q->bytes_left_in_line == 0) ? 0 : 1;
+                return bytes_to_copy;
+        }
+
+        /* copy the data to video buffer */
+        cx231xx_do_vbi_copy(dev, dma_q, p_line, bytes_to_copy);
+
+        dma_q->pos += bytes_to_copy;
+        dma_q->bytes_left_in_line -= bytes_to_copy;
+
+        if (dma_q->bytes_left_in_line == 0) {
+
+                dma_q->bytes_left_in_line = _line_size;
+                dma_q->lines_completed++;
+                dma_q->is_partial_line = 0;
+
+                if (cx231xx_is_vbi_buffer_done(dev, dma_q) && buf) {
+
+                        vbi_buffer_filled(dev, dma_q, buf);
+
+                        dma_q->pos = 0;
+                        buf = NULL;
+                        dma_q->lines_completed = 0;
+                }
+        }
+
+        return bytes_to_copy;
+}
+
+/*
+ * video-buf generic routine to get the next available buffer
+ */
+static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
+                                    struct cx231xx_buffer **buf)
+{
+        struct cx231xx_video_mode *vmode =
+            container_of(dma_q, struct cx231xx_video_mode, vidq);
+        struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
+        char *outp;
+
+        if (list_empty(&dma_q->active)) {
+                cx231xx_err(DRIVER_NAME ": No active queue to serve\n");
+                dev->vbi_mode.isoc_ctl.buf = NULL;
+                *buf = NULL;
+                return;
+        }
+
+        /* Get the next buffer */
+        *buf = list_entry(dma_q->active.next, struct cx231xx_buffer, vb.queue);
+
+        /* Cleans up buffer - Usefull for testing for frame/URB loss */
+        outp = videobuf_to_vmalloc(&(*buf)->vb);
+        memset(outp, 0, (*buf)->vb.size);
+
+        dev->vbi_mode.isoc_ctl.buf = *buf;
+
+        return;
+}
+
+void cx231xx_reset_vbi_buffer(struct cx231xx *dev,
+                              struct cx231xx_dmaqueue *dma_q)
+{
+        struct cx231xx_buffer *buf;
+
+        buf = dev->vbi_mode.isoc_ctl.buf;
+
+        if (buf == NULL) {
+                /* first try to get the buffer */
+                get_next_vbi_buf(dma_q, &buf);
+
+                dma_q->pos = 0;
+                dma_q->current_field = -1;
+        }
+
+        dma_q->bytes_left_in_line = dev->width << 1;
+        dma_q->lines_completed = 0;
+}
+
+int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
+                        u8 *p_buffer, u32 bytes_to_copy)
+{
+        u8 *p_out_buffer = NULL;
+        u32 current_line_bytes_copied = 0;
+        struct cx231xx_buffer *buf;
+        u32 _line_size = dev->width << 1;
+        void *startwrite;
+        int offset, lencopy;
+
+        buf = dev->vbi_mode.isoc_ctl.buf;
+
+        if (buf == NULL)
+                return -EINVAL;
+
+        p_out_buffer = videobuf_to_vmalloc(&buf->vb);
+
+        if (dma_q->bytes_left_in_line != _line_size) {
+                current_line_bytes_copied =
+                    _line_size - dma_q->bytes_left_in_line;
+        }
+
+        offset = (dma_q->lines_completed * _line_size) +
+                 current_line_bytes_copied;
+
+        /* prepare destination address */
+        startwrite = p_out_buffer + offset;
+
+        lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
+                  bytes_to_copy : dma_q->bytes_left_in_line;
+
+        memcpy(startwrite, p_buffer, lencopy);
+
+        return 0;
+}
+
+u8 cx231xx_is_vbi_buffer_done(struct cx231xx *dev,
+                              struct cx231xx_dmaqueue *dma_q)
+{
+        u32 height = 0;
+
+        height = ((dev->norm & V4L2_STD_625_50) ?
+                  PAL_VBI_LINES : NTSC_VBI_LINES);
+        return (dma_q->lines_completed == height) ? 1 : 0;
+}