V4L/DVB (5583): VIDEO4LINUX-2: Replace MINOR() with a call to iminor().

[linux-2.6/cjktty.git] / drivers / media / video / ivtv / ivtv-fileops.c

/*
    file operation functions
    Copyright (C) 2003-2004  Kevin Thayer <nufan_wfk at yahoo.com>
    Copyright (C) 2004  Chris Kennedy <c@groovy.org>
    Copyright (C) 2005-2007  Hans Verkuil <hverkuil@xs4all.nl>

    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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "ivtv-driver.h"
#include "ivtv-fileops.h"
#include "ivtv-i2c.h"
#include "ivtv-queue.h"
#include "ivtv-udma.h"
#include "ivtv-irq.h"
#include "ivtv-vbi.h"
#include "ivtv-mailbox.h"
#include "ivtv-audio.h"
#include "ivtv-streams.h"
#include "ivtv-yuv.h"
#include "ivtv-controls.h"
#include "ivtv-ioctl.h"

/* This function tries to claim the stream for a specific file descriptor.
   If no one else is using this stream then the stream is claimed and
   associated VBI streams are also automatically claimed.
   Possible error returns: -EBUSY if someone else has claimed
   the stream or 0 on success. */
int ivtv_claim_stream(struct ivtv_open_id *id, int type)
{
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[type];
        struct ivtv_stream *s_vbi;
        int vbi_type;

        if (test_and_set_bit(IVTV_F_S_CLAIMED, &s->s_flags)) {
                /* someone already claimed this stream */
                if (s->id == id->open_id) {
                        /* yes, this file descriptor did. So that's OK. */
                        return 0;
                }
                if (s->id == -1 && (type == IVTV_DEC_STREAM_TYPE_VBI ||
                                         type == IVTV_ENC_STREAM_TYPE_VBI)) {
                        /* VBI is handled already internally, now also assign
                           the file descriptor to this stream for external
                           reading of the stream. */
                        s->id = id->open_id;
                        IVTV_DEBUG_INFO("Start Read VBI\n");
                        return 0;
                }
                /* someone else is using this stream already */
                IVTV_DEBUG_INFO("Stream %d is busy\n", type);
                return -EBUSY;
        }
        s->id = id->open_id;
        if (type == IVTV_DEC_STREAM_TYPE_VBI) {
                /* Enable reinsertion interrupt */
                ivtv_clear_irq_mask(itv, IVTV_IRQ_DEC_VBI_RE_INSERT);
        }

        /* IVTV_DEC_STREAM_TYPE_MPG needs to claim IVTV_DEC_STREAM_TYPE_VBI,
           IVTV_ENC_STREAM_TYPE_MPG needs to claim IVTV_ENC_STREAM_TYPE_VBI
           (provided VBI insertion is on and sliced VBI is selected), for all
           other streams we're done */
        if (type == IVTV_DEC_STREAM_TYPE_MPG) {
                vbi_type = IVTV_DEC_STREAM_TYPE_VBI;
        } else if (type == IVTV_ENC_STREAM_TYPE_MPG &&
                   itv->vbi.insert_mpeg && itv->vbi.sliced_in->service_set) {
                vbi_type = IVTV_ENC_STREAM_TYPE_VBI;
        } else {
                return 0;
        }
        s_vbi = &itv->streams[vbi_type];

        if (!test_and_set_bit(IVTV_F_S_CLAIMED, &s_vbi->s_flags)) {
                /* Enable reinsertion interrupt */
                if (vbi_type == IVTV_DEC_STREAM_TYPE_VBI)
                        ivtv_clear_irq_mask(itv, IVTV_IRQ_DEC_VBI_RE_INSERT);
        }
        /* mark that it is used internally */
        set_bit(IVTV_F_S_INTERNAL_USE, &s_vbi->s_flags);
        return 0;
}

/* This function releases a previously claimed stream. It will take into
   account associated VBI streams. */
void ivtv_release_stream(struct ivtv_stream *s)
{
        struct ivtv *itv = s->itv;
        struct ivtv_stream *s_vbi;

        s->id = -1;
        if ((s->type == IVTV_DEC_STREAM_TYPE_VBI || s->type == IVTV_ENC_STREAM_TYPE_VBI) &&
                test_bit(IVTV_F_S_INTERNAL_USE, &s->s_flags)) {
                /* this stream is still in use internally */
                return;
        }
        if (!test_and_clear_bit(IVTV_F_S_CLAIMED, &s->s_flags)) {
                IVTV_DEBUG_WARN("Release stream %s not in use!\n", s->name);
                return;
        }

        ivtv_flush_queues(s);

        /* disable reinsertion interrupt */
        if (s->type == IVTV_DEC_STREAM_TYPE_VBI)
                ivtv_set_irq_mask(itv, IVTV_IRQ_DEC_VBI_RE_INSERT);

        /* IVTV_DEC_STREAM_TYPE_MPG needs to release IVTV_DEC_STREAM_TYPE_VBI,
           IVTV_ENC_STREAM_TYPE_MPG needs to release IVTV_ENC_STREAM_TYPE_VBI,
           for all other streams we're done */
        if (s->type == IVTV_DEC_STREAM_TYPE_MPG)
                s_vbi = &itv->streams[IVTV_DEC_STREAM_TYPE_VBI];
        else if (s->type == IVTV_ENC_STREAM_TYPE_MPG)
                s_vbi = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
        else
                return;

        /* clear internal use flag */
        if (!test_and_clear_bit(IVTV_F_S_INTERNAL_USE, &s_vbi->s_flags)) {
                /* was already cleared */
                return;
        }
        if (s_vbi->id != -1) {
                /* VBI stream still claimed by a file descriptor */
                return;
        }
        /* disable reinsertion interrupt */
        if (s_vbi->type == IVTV_DEC_STREAM_TYPE_VBI)
                ivtv_set_irq_mask(itv, IVTV_IRQ_DEC_VBI_RE_INSERT);
        clear_bit(IVTV_F_S_CLAIMED, &s_vbi->s_flags);
        ivtv_flush_queues(s_vbi);
}

static void ivtv_dualwatch(struct ivtv *itv)
{
        struct v4l2_tuner vt;
        u16 new_bitmap;
        u16 new_stereo_mode;
        const u16 stereo_mask = 0x0300;
        const u16 dual = 0x0200;

        new_stereo_mode = itv->params.audio_properties & stereo_mask;
        memset(&vt, 0, sizeof(vt));
        ivtv_call_i2c_clients(itv, VIDIOC_G_TUNER, &vt);
        if (vt.audmode == V4L2_TUNER_MODE_LANG1_LANG2 && (vt.rxsubchans & V4L2_TUNER_SUB_LANG2))
                new_stereo_mode = dual;

        if (new_stereo_mode == itv->dualwatch_stereo_mode)
                return;

        new_bitmap = new_stereo_mode | (itv->params.audio_properties & ~stereo_mask);

        IVTV_DEBUG_INFO("dualwatch: change stereo flag from 0x%x to 0x%x. new audio_bitmask=0x%ux\n",
                           itv->dualwatch_stereo_mode, new_stereo_mode, new_bitmap);

        if (ivtv_vapi(itv, CX2341X_ENC_SET_AUDIO_PROPERTIES, 1, new_bitmap) == 0) {
                itv->dualwatch_stereo_mode = new_stereo_mode;
                return;
        }
        IVTV_DEBUG_INFO("dualwatch: changing stereo flag failed\n");
}

static void ivtv_update_pgm_info(struct ivtv *itv)
{
        u32 wr_idx = (read_enc(itv->pgm_info_offset) - itv->pgm_info_offset - 4) / 24;
        int cnt;
        int i = 0;

        if (wr_idx >= itv->pgm_info_num) {
                IVTV_DEBUG_WARN("Invalid PGM index %d (>= %d)\n", wr_idx, itv->pgm_info_num);
                return;
        }
        cnt = (wr_idx + itv->pgm_info_num - itv->pgm_info_write_idx) % itv->pgm_info_num;
        while (i < cnt) {
                int idx = (itv->pgm_info_write_idx + i) % itv->pgm_info_num;
                struct v4l2_enc_idx_entry *e = itv->pgm_info + idx;
                u32 addr = itv->pgm_info_offset + 4 + idx * 24;
                const int mapping[] = { V4L2_ENC_IDX_FRAME_P, V4L2_ENC_IDX_FRAME_I, V4L2_ENC_IDX_FRAME_B, 0 };

                e->offset = read_enc(addr + 4) + ((u64)read_enc(addr + 8) << 32);
                if (e->offset > itv->mpg_data_received) {
                        break;
                }
                e->offset += itv->vbi_data_inserted;
                e->length = read_enc(addr);
                e->pts = read_enc(addr + 16) + ((u64)(read_enc(addr + 20) & 1) << 32);
                e->flags = mapping[read_enc(addr + 12) & 3];
                i++;
        }
        itv->pgm_info_write_idx = (itv->pgm_info_write_idx + i) % itv->pgm_info_num;
}

static struct ivtv_buffer *ivtv_get_buffer(struct ivtv_stream *s, int non_block, int *err)
{
        struct ivtv *itv = s->itv;
        struct ivtv_stream *s_vbi = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
        struct ivtv_buffer *buf;
        DEFINE_WAIT(wait);

        *err = 0;
        while (1) {
                if (s->type == IVTV_ENC_STREAM_TYPE_MPG) {
                        /* Process pending program info updates and pending VBI data */
                        ivtv_update_pgm_info(itv);

                        if (jiffies - itv->dualwatch_jiffies > HZ) {
                                itv->dualwatch_jiffies = jiffies;
                                ivtv_dualwatch(itv);
                        }

                        if (test_bit(IVTV_F_S_INTERNAL_USE, &s_vbi->s_flags) &&
                            !test_bit(IVTV_F_S_APPL_IO, &s_vbi->s_flags)) {
                                while ((buf = ivtv_dequeue(s_vbi, &s_vbi->q_full))) {
                                        /* byteswap and process VBI data */
                                        ivtv_process_vbi_data(itv, buf, s_vbi->dma_pts, s_vbi->type);
                                        ivtv_enqueue(s_vbi, buf, &s_vbi->q_free);
                                }
                        }
                        buf = &itv->vbi.sliced_mpeg_buf;
                        if (buf->readpos != buf->bytesused) {
                                return buf;
                        }
                }

                /* do we have leftover data? */
                buf = ivtv_dequeue(s, &s->q_io);
                if (buf)
                        return buf;

                /* do we have new data? */
                buf = ivtv_dequeue(s, &s->q_full);
                if (buf) {
                        if (!test_and_clear_bit(IVTV_F_B_NEED_BUF_SWAP, &buf->b_flags))
                                return buf;
                        if (s->type == IVTV_ENC_STREAM_TYPE_MPG)
                                /* byteswap MPG data */
                                ivtv_buf_swap(buf);
                        else if (s->type != IVTV_DEC_STREAM_TYPE_VBI) {
                                /* byteswap and process VBI data */
                                ivtv_process_vbi_data(itv, buf, s->dma_pts, s->type);
                        }
                        return buf;
                }
                /* return if file was opened with O_NONBLOCK */
                if (non_block) {
                        *err = -EAGAIN;
                        return NULL;
                }

                /* return if end of stream */
                if (s->type != IVTV_DEC_STREAM_TYPE_VBI && !test_bit(IVTV_F_S_STREAMING, &s->s_flags)) {
                        clear_bit(IVTV_F_S_STREAMOFF, &s->s_flags);
                        IVTV_DEBUG_INFO("EOS %s\n", s->name);
                        return NULL;
                }

                /* wait for more data to arrive */
                prepare_to_wait(&s->waitq, &wait, TASK_INTERRUPTIBLE);
                /* New buffers might have become available before we were added to the waitqueue */
                if (!s->q_full.buffers)
                        schedule();
                finish_wait(&s->waitq, &wait);
                if (signal_pending(current)) {
                        /* return if a signal was received */
                        IVTV_DEBUG_INFO("User stopped %s\n", s->name);
                        *err = -EINTR;
                        return NULL;
                }
        }
}

static void ivtv_setup_sliced_vbi_buf(struct ivtv *itv)
{
        int idx = itv->vbi.inserted_frame % IVTV_VBI_FRAMES;

        itv->vbi.sliced_mpeg_buf.buf = itv->vbi.sliced_mpeg_data[idx];
        itv->vbi.sliced_mpeg_buf.bytesused = itv->vbi.sliced_mpeg_size[idx];
        itv->vbi.sliced_mpeg_buf.readpos = 0;
}

static size_t ivtv_copy_buf_to_user(struct ivtv_stream *s, struct ivtv_buffer *buf,
                char __user *ubuf, size_t ucount)
{
        struct ivtv *itv = s->itv;
        size_t len = buf->bytesused - buf->readpos;

        if (len > ucount) len = ucount;
        if (itv->vbi.insert_mpeg && s->type == IVTV_ENC_STREAM_TYPE_MPG &&
            itv->vbi.sliced_in->service_set && buf != &itv->vbi.sliced_mpeg_buf) {
                const char *start = buf->buf + buf->readpos;
                const char *p = start + 1;
                const u8 *q;
                u8 ch = itv->search_pack_header ? 0xba : 0xe0;
                int stuffing, i;

                while (start + len > p && (q = memchr(p, 0, start + len - p))) {
                        p = q + 1;
                        if ((char *)q + 15 >= buf->buf + buf->bytesused ||
                            q[1] != 0 || q[2] != 1 || q[3] != ch) {
                                continue;
                        }
                        if (!itv->search_pack_header) {
                                if ((q[6] & 0xc0) != 0x80)
                                        continue;
                                if (((q[7] & 0xc0) == 0x80 && (q[9] & 0xf0) == 0x20) ||
                                    ((q[7] & 0xc0) == 0xc0 && (q[9] & 0xf0) == 0x30)) {
                                        ch = 0xba;
                                        itv->search_pack_header = 1;
                                        p = q + 9;
                                }
                                continue;
                        }
                        stuffing = q[13] & 7;
                        /* all stuffing bytes must be 0xff */
                        for (i = 0; i < stuffing; i++)
                                if (q[14 + i] != 0xff)
                                        break;
                        if (i == stuffing && (q[4] & 0xc4) == 0x44 && (q[12] & 3) == 3 &&
                                        q[14 + stuffing] == 0 && q[15 + stuffing] == 0 &&
                                        q[16 + stuffing] == 1) {
                                itv->search_pack_header = 0;
                                len = (char *)q - start;
                                ivtv_setup_sliced_vbi_buf(itv);
                                break;
                        }
                }
        }
        if (copy_to_user(ubuf, (u8 *)buf->buf + buf->readpos, len)) {
                IVTV_DEBUG_WARN("copy %zd bytes to user failed for %s\n", len, s->name);
                return -EFAULT;
        }
        /*IVTV_INFO("copied %lld %d %d %d %d %d vbi %d\n", itv->mpg_data_received, len, ucount,
                        buf->readpos, buf->bytesused, buf->bytesused - buf->readpos - len,
                        buf == &itv->vbi.sliced_mpeg_buf); */
        buf->readpos += len;
        if (s->type == IVTV_ENC_STREAM_TYPE_MPG && buf != &itv->vbi.sliced_mpeg_buf)
                itv->mpg_data_received += len;
        return len;
}

static ssize_t ivtv_read(struct ivtv_stream *s, char __user *ubuf, size_t tot_count, int non_block)
{
        struct ivtv *itv = s->itv;
        size_t tot_written = 0;
        int single_frame = 0;

        if (atomic_read(&itv->capturing) == 0 && s->id == -1) {
                /* shouldn't happen */
                IVTV_DEBUG_WARN("Stream %s not initialized before read\n", s->name);
                return -EIO;
        }

        /* Each VBI buffer is one frame, the v4l2 API says that for VBI the frames should
           arrive one-by-one, so make sure we never output more than one VBI frame at a time */
        if (s->type == IVTV_DEC_STREAM_TYPE_VBI ||
                        (s->type == IVTV_ENC_STREAM_TYPE_VBI && itv->vbi.sliced_in->service_set))
                single_frame = 1;

        for (;;) {
                struct ivtv_buffer *buf;
                int rc;

                buf = ivtv_get_buffer(s, non_block, &rc);
                if (buf == NULL && rc == -EAGAIN && tot_written)
                        break;
                if (buf == NULL)
                        return rc;
                rc = ivtv_copy_buf_to_user(s, buf, ubuf + tot_written, tot_count - tot_written);
                if (buf != &itv->vbi.sliced_mpeg_buf) {
                        ivtv_enqueue(s, buf, (buf->readpos == buf->bytesused) ? &s->q_free : &s->q_io);
                }
                else if (buf->readpos == buf->bytesused) {
                        int idx = itv->vbi.inserted_frame % IVTV_VBI_FRAMES;
                        itv->vbi.sliced_mpeg_size[idx] = 0;
                        itv->vbi.inserted_frame++;
                        itv->vbi_data_inserted += buf->bytesused;
                }
                if (rc < 0)
                        return rc;
                tot_written += rc;

                if (tot_written == tot_count || single_frame)
                        break;
        }
        return tot_written;
}

static ssize_t ivtv_read_pos(struct ivtv_stream *s, char __user *ubuf, size_t count,
                        loff_t *pos, int non_block)
{
        ssize_t rc = count ? ivtv_read(s, ubuf, count, non_block) : 0;
        struct ivtv *itv = s->itv;

        IVTV_DEBUG_INFO("read %zd from %s, got %zd\n", count, s->name, rc);
        if (rc > 0)
                pos += rc;
        return rc;
}

int ivtv_start_capture(struct ivtv_open_id *id)
{
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];
        struct ivtv_stream *s_vbi;

        if (s->type == IVTV_ENC_STREAM_TYPE_RAD ||
            s->type == IVTV_DEC_STREAM_TYPE_MPG ||
            s->type == IVTV_DEC_STREAM_TYPE_YUV ||
            s->type == IVTV_DEC_STREAM_TYPE_VOUT) {
                /* you cannot read from these stream types. */
                return -EPERM;
        }

        /* Try to claim this stream. */
        if (ivtv_claim_stream(id, s->type))
                return -EBUSY;

        /* This stream does not need to start capturing */
        if (s->type == IVTV_DEC_STREAM_TYPE_VBI) {
                set_bit(IVTV_F_S_APPL_IO, &s->s_flags);
                return 0;
        }

        /* If capture is already in progress, then we also have to
           do nothing extra. */
        if (test_bit(IVTV_F_S_STREAMOFF, &s->s_flags) || test_and_set_bit(IVTV_F_S_STREAMING, &s->s_flags)) {
                set_bit(IVTV_F_S_APPL_IO, &s->s_flags);
                return 0;
        }

        /* Start VBI capture if required */
        s_vbi = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
        if (s->type == IVTV_ENC_STREAM_TYPE_MPG &&
            test_bit(IVTV_F_S_INTERNAL_USE, &s_vbi->s_flags) &&
            !test_and_set_bit(IVTV_F_S_STREAMING, &s_vbi->s_flags)) {
                /* Note: the IVTV_ENC_STREAM_TYPE_VBI is claimed
                   automatically when the MPG stream is claimed.
                   We only need to start the VBI capturing. */
                if (ivtv_start_v4l2_encode_stream(s_vbi)) {
                        IVTV_DEBUG_WARN("VBI capture start failed\n");

                        /* Failure, clean up and return an error */
                        clear_bit(IVTV_F_S_STREAMING, &s_vbi->s_flags);
                        clear_bit(IVTV_F_S_STREAMING, &s->s_flags);
                        /* also releases the associated VBI stream */
                        ivtv_release_stream(s);
                        return -EIO;
                }
                IVTV_DEBUG_INFO("VBI insertion started\n");
        }

        /* Tell the card to start capturing */
        if (!ivtv_start_v4l2_encode_stream(s)) {
                /* We're done */
                set_bit(IVTV_F_S_APPL_IO, &s->s_flags);
                /* Resume a possibly paused encoder */
                if (test_and_clear_bit(IVTV_F_I_ENC_PAUSED, &itv->i_flags))
                        ivtv_vapi(itv, CX2341X_ENC_PAUSE_ENCODER, 1, 1);
                return 0;
        }

        /* failure, clean up */
        IVTV_DEBUG_WARN("Failed to start capturing for stream %s\n", s->name);

        /* Note: the IVTV_ENC_STREAM_TYPE_VBI is released
           automatically when the MPG stream is released.
           We only need to stop the VBI capturing. */
        if (s->type == IVTV_ENC_STREAM_TYPE_MPG &&
            test_bit(IVTV_F_S_STREAMING, &s_vbi->s_flags)) {
                ivtv_stop_v4l2_encode_stream(s_vbi, 0);
                clear_bit(IVTV_F_S_STREAMING, &s_vbi->s_flags);
        }
        clear_bit(IVTV_F_S_STREAMING, &s->s_flags);
        ivtv_release_stream(s);
        return -EIO;
}

ssize_t ivtv_v4l2_read(struct file * filp, char __user *buf, size_t count, loff_t * pos)
{
        struct ivtv_open_id *id = filp->private_data;
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];
        int rc;

        IVTV_DEBUG_IOCTL("read %zd bytes from %s\n", count, s->name);

        rc = ivtv_start_capture(id);
        if (rc)
                return rc;
        return ivtv_read_pos(s, buf, count, pos, filp->f_flags & O_NONBLOCK);
}

int ivtv_start_decoding(struct ivtv_open_id *id, int speed)
{
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];

        if (atomic_read(&itv->decoding) == 0) {
                if (ivtv_claim_stream(id, s->type)) {
                        /* someone else is using this stream already */
                        IVTV_DEBUG_WARN("start decode, stream already claimed\n");
                        return -EBUSY;
                }
                ivtv_start_v4l2_decode_stream(s, 0);
        }
        if (s->type == IVTV_DEC_STREAM_TYPE_MPG)
                return ivtv_set_speed(itv, speed);
        return 0;
}

ssize_t ivtv_v4l2_write(struct file *filp, const char __user *user_buf, size_t count, loff_t *pos)
{
        struct ivtv_open_id *id = filp->private_data;
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];
        struct ivtv_buffer *buf;
        struct ivtv_queue q;
        int bytes_written = 0;
        int mode;
        int rc;
        DEFINE_WAIT(wait);

        IVTV_DEBUG_IOCTL("write %zd bytes to %s\n", count, s->name);

        if (s->type != IVTV_DEC_STREAM_TYPE_MPG &&
            s->type != IVTV_DEC_STREAM_TYPE_YUV &&
            s->type != IVTV_DEC_STREAM_TYPE_VOUT)
                /* not decoder streams */
                return -EPERM;

        /* Try to claim this stream */
        if (ivtv_claim_stream(id, s->type))
                return -EBUSY;

        /* This stream does not need to start any decoding */
        if (s->type == IVTV_DEC_STREAM_TYPE_VOUT) {
                set_bit(IVTV_F_S_APPL_IO, &s->s_flags);
                return ivtv_write_vbi(itv, user_buf, count);
        }

        mode = s->type == IVTV_DEC_STREAM_TYPE_MPG ? OUT_MPG : OUT_YUV;

        if (ivtv_set_output_mode(itv, mode) != mode) {
            ivtv_release_stream(s);
            return -EBUSY;
        }
        ivtv_queue_init(&q);
        set_bit(IVTV_F_S_APPL_IO, &s->s_flags);

retry:
        for (;;) {
                /* Gather buffers */
                while (q.length - q.bytesused < count && (buf = ivtv_dequeue(s, &s->q_io)))
                        ivtv_enqueue(s, buf, &q);
                while (q.length - q.bytesused < count && (buf = ivtv_dequeue(s, &s->q_free))) {
                        ivtv_enqueue(s, buf, &q);
                }
                if (q.buffers)
                        break;
                if (filp->f_flags & O_NONBLOCK)
                        return -EAGAIN;
                prepare_to_wait(&s->waitq, &wait, TASK_INTERRUPTIBLE);
                /* New buffers might have become free before we were added to the waitqueue */
                if (!s->q_free.buffers)
                        schedule();
                finish_wait(&s->waitq, &wait);
                if (signal_pending(current)) {
                        IVTV_DEBUG_INFO("User stopped %s\n", s->name);
                        return -EINTR;
                }
        }

        /* copy user data into buffers */
        while ((buf = ivtv_dequeue(s, &q))) {
                /* Make sure we really got all the user data */
                rc = ivtv_buf_copy_from_user(s, buf, user_buf, count);

                if (rc < 0) {
                        ivtv_queue_move(s, &q, NULL, &s->q_free, 0);
                        return rc;
                }
                user_buf += rc;
                count -= rc;
                bytes_written += rc;

                if (buf->bytesused != s->buf_size) {
                        /* incomplete, leave in q_io for next time */
                        ivtv_enqueue(s, buf, &s->q_io);
                        break;
                }
                /* Byteswap MPEG buffer */
                if (s->type == IVTV_DEC_STREAM_TYPE_MPG)
                        ivtv_buf_swap(buf);
                ivtv_enqueue(s, buf, &s->q_full);
        }

        /* Start decoder (returns 0 if already started) */
        rc = ivtv_start_decoding(id, itv->speed);
        if (rc) {
                IVTV_DEBUG_WARN("Failed start decode stream %s\n", s->name);

                /* failure, clean up */
                clear_bit(IVTV_F_S_STREAMING, &s->s_flags);
                clear_bit(IVTV_F_S_APPL_IO, &s->s_flags);
                return rc;
        }
        if (test_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags)) {
                if (s->q_full.length >= itv->dma_data_req_size) {
                        int got_sig;

                        prepare_to_wait(&itv->dma_waitq, &wait, TASK_INTERRUPTIBLE);
                        while (!(got_sig = signal_pending(current)) &&
                                        test_bit(IVTV_F_S_DMA_PENDING, &s->s_flags)) {
                                schedule();
                        }
                        finish_wait(&itv->dma_waitq, &wait);
                        if (got_sig) {
                                IVTV_DEBUG_INFO("User interrupted %s\n", s->name);
                                return -EINTR;
                        }

                        clear_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
                        ivtv_queue_move(s, &s->q_full, NULL, &s->q_predma, itv->dma_data_req_size);
                        ivtv_dma_stream_dec_prepare(s, itv->dma_data_req_offset + IVTV_DECODER_OFFSET, 1);
                }
        }
        /* more user data is available, wait until buffers become free
           to transfer the rest. */
        if (count && !(filp->f_flags & O_NONBLOCK))
                goto retry;
        IVTV_DEBUG_INFO("Wrote %d bytes to %s (%d)\n", bytes_written, s->name, s->q_full.bytesused);
        return bytes_written;
}

unsigned int ivtv_v4l2_dec_poll(struct file *filp, poll_table *wait)
{
        struct ivtv_open_id *id = filp->private_data;
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];
        int res = 0;

        /* add stream's waitq to the poll list */
        poll_wait(filp, &s->waitq, wait);

        set_bit(IVTV_F_I_EV_VSYNC_ENABLED, &itv->i_flags);
        if (test_bit(IVTV_F_I_EV_VSYNC, &itv->i_flags) ||
            test_bit(IVTV_F_I_EV_DEC_STOPPED, &itv->i_flags))
                res = POLLPRI;

        /* Allow write if buffers are available for writing */
        if (s->q_free.buffers)
                res |= POLLOUT | POLLWRNORM;
        return res;
}

unsigned int ivtv_v4l2_enc_poll(struct file *filp, poll_table * wait)
{
        struct ivtv_open_id *id = filp->private_data;
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];
        int eof = test_bit(IVTV_F_S_STREAMOFF, &s->s_flags);

        /* Start a capture if there is none */
        if (!eof && !test_bit(IVTV_F_S_STREAMING, &s->s_flags)) {
                int rc = ivtv_start_capture(id);

                if (rc) {
                        IVTV_DEBUG_INFO("Could not start capture for %s (%d)\n",
                                        s->name, rc);
                        return POLLERR;
                }
        }

        /* add stream's waitq to the poll list */
        poll_wait(filp, &s->waitq, wait);

        if (eof || s->q_full.length)
                return POLLIN | POLLRDNORM;
        return 0;
}

void ivtv_stop_capture(struct ivtv_open_id *id, int gop_end)
{
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];

        IVTV_DEBUG_IOCTL("close() of %s\n", s->name);

        /* 'Unclaim' this stream */

        /* Stop capturing */
        if (test_bit(IVTV_F_S_STREAMING, &s->s_flags)) {
                struct ivtv_stream *s_vbi = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];

                IVTV_DEBUG_INFO("close stopping capture\n");
                /* Special case: a running VBI capture for VBI insertion
                   in the mpeg stream. Need to stop that too. */
                if (id->type == IVTV_ENC_STREAM_TYPE_MPG &&
                    test_bit(IVTV_F_S_STREAMING, &s_vbi->s_flags) &&
                    !test_bit(IVTV_F_S_APPL_IO, &s_vbi->s_flags)) {
                        IVTV_DEBUG_INFO("close stopping embedded VBI capture\n");
                        ivtv_stop_v4l2_encode_stream(s_vbi, 0);
                }
                if ((id->type == IVTV_DEC_STREAM_TYPE_VBI ||
                     id->type == IVTV_ENC_STREAM_TYPE_VBI) &&
                    test_bit(IVTV_F_S_INTERNAL_USE, &s->s_flags)) {
                        /* Also used internally, don't stop capturing */
                        s->id = -1;
                }
                else {
                        ivtv_stop_v4l2_encode_stream(s, gop_end);
                }
        }
        clear_bit(IVTV_F_S_APPL_IO, &s->s_flags);
        clear_bit(IVTV_F_S_STREAMOFF, &s->s_flags);

        ivtv_release_stream(s);
}

static void ivtv_stop_decoding(struct ivtv_open_id *id, int flags, u64 pts)
{
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];

        IVTV_DEBUG_IOCTL("close() of %s\n", s->name);

        /* Stop decoding */
        if (test_bit(IVTV_F_S_STREAMING, &s->s_flags)) {
                IVTV_DEBUG_INFO("close stopping decode\n");

                ivtv_stop_v4l2_decode_stream(s, flags, pts);
        }
        clear_bit(IVTV_F_S_APPL_IO, &s->s_flags);
        clear_bit(IVTV_F_S_STREAMOFF, &s->s_flags);
        if (id->type == IVTV_DEC_STREAM_TYPE_YUV && test_bit(IVTV_F_I_DECODING_YUV, &itv->i_flags)) {
                /* Restore registers we've changed & clean up any mess we've made */
                ivtv_yuv_close(itv);
        }
        if (s->type == IVTV_DEC_STREAM_TYPE_YUV && itv->output_mode == OUT_YUV)
            itv->output_mode = OUT_NONE;
        else if (s->type == IVTV_DEC_STREAM_TYPE_MPG && itv->output_mode == OUT_MPG)
            itv->output_mode = OUT_NONE;

        itv->speed = 0;
        ivtv_release_stream(s);
}

int ivtv_v4l2_close(struct inode *inode, struct file *filp)
{
        struct ivtv_open_id *id = filp->private_data;
        struct ivtv *itv = id->itv;
        struct ivtv_stream *s = &itv->streams[id->type];

        IVTV_DEBUG_IOCTL("close() of %s\n", s->name);

        v4l2_prio_close(&itv->prio, &id->prio);

        /* Easy case first: this stream was never claimed by us */
        if (s->id != id->open_id) {
                kfree(id);
                return 0;
        }

        /* 'Unclaim' this stream */

        /* Stop radio */
        if (id->type == IVTV_ENC_STREAM_TYPE_RAD) {
                /* Closing radio device, return to TV mode */
                ivtv_mute(itv);
                /* Mark that the radio is no longer in use */
                clear_bit(IVTV_F_I_RADIO_USER, &itv->i_flags);
                /* Switch tuner to TV */
                ivtv_call_i2c_clients(itv, VIDIOC_S_STD, &itv->std);
                /* Select correct audio input (i.e. TV tuner or Line in) */
                ivtv_audio_set_io(itv);
                /* Done! Unmute and continue. */
                ivtv_unmute(itv);
                ivtv_release_stream(s);
        } else if (s->type >= IVTV_DEC_STREAM_TYPE_MPG) {
                ivtv_stop_decoding(id, VIDEO_CMD_STOP_TO_BLACK | VIDEO_CMD_STOP_IMMEDIATELY, 0);
        } else {
                ivtv_stop_capture(id, 0);
        }
        kfree(id);
        return 0;
}

int ivtv_v4l2_open(struct inode *inode, struct file *filp)
{
        int x, y = 0;
        struct ivtv_open_id *item;
        struct ivtv *itv = NULL;
        struct ivtv_stream *s = NULL;
        int minor = iminor(inode);

        /* Find which card this open was on */
        spin_lock(&ivtv_cards_lock);
        for (x = 0; itv == NULL && x < ivtv_cards_active; x++) {
                /* find out which stream this open was on */
                for (y = 0; y < IVTV_MAX_STREAMS; y++) {
                        s = &ivtv_cards[x]->streams[y];
                        if (s->v4l2dev && s->v4l2dev->minor == minor) {
                                itv = ivtv_cards[x];
                                break;
                        }
                }
        }
        spin_unlock(&ivtv_cards_lock);

        if (itv == NULL) {
                /* Couldn't find a device registered
                   on that minor, shouldn't happen! */
                printk(KERN_WARNING "ivtv: no ivtv device found on minor %d\n", minor);
                return -ENXIO;
        }

        if (y == IVTV_DEC_STREAM_TYPE_MPG &&
                test_bit(IVTV_F_S_CLAIMED, &itv->streams[IVTV_DEC_STREAM_TYPE_YUV].s_flags))
                return -EBUSY;

        if (y == IVTV_DEC_STREAM_TYPE_YUV &&
                test_bit(IVTV_F_S_CLAIMED, &itv->streams[IVTV_DEC_STREAM_TYPE_MPG].s_flags))
                return -EBUSY;

        if (y == IVTV_DEC_STREAM_TYPE_YUV) {
                if (read_reg(0x82c) == 0) {
                        IVTV_ERR("Tried to open YUV output device but need to send data to mpeg decoder before it can be used\n");
                        /* return -ENODEV; */
                }
                ivtv_udma_alloc(itv);
        }

        /* Allocate memory */
        item = kmalloc(sizeof(struct ivtv_open_id), GFP_KERNEL);
        if (NULL == item) {
                IVTV_DEBUG_WARN("nomem on v4l2 open\n");
                return -ENOMEM;
        }
        item->itv = itv;
        item->type = y;
        v4l2_prio_open(&itv->prio, &item->prio);

        item->open_id = itv->open_id++;
        filp->private_data = item;

        if (item->type == IVTV_ENC_STREAM_TYPE_RAD) {
                /* Try to claim this stream */
                if (ivtv_claim_stream(item, item->type)) {
                        /* No, it's already in use */
                        kfree(item);
                        return -EBUSY;
                }

                /* We have the radio */
                ivtv_mute(itv);
                /* Switch tuner to radio */
                ivtv_call_i2c_clients(itv, AUDC_SET_RADIO, NULL);
                /* Mark that the radio is being used. */
                set_bit(IVTV_F_I_RADIO_USER, &itv->i_flags);
                /* Select the correct audio input (i.e. radio tuner) */
                ivtv_audio_set_io(itv);
                /* Done! Unmute and continue. */
                ivtv_unmute(itv);
        }

        /* YUV or MPG Decoding Mode? */
        if (y == IVTV_DEC_STREAM_TYPE_MPG)
                clear_bit(IVTV_F_I_DEC_YUV, &itv->i_flags);
        else if (y == IVTV_DEC_STREAM_TYPE_YUV)
        {
                set_bit(IVTV_F_I_DEC_YUV, &itv->i_flags);
        }

        return 0;
}

void ivtv_mute(struct ivtv *itv)
{
        struct v4l2_control ctrl = { V4L2_CID_AUDIO_MUTE, 1 };

        /* Mute sound to avoid pop */
        ivtv_control_ioctls(itv, VIDIOC_S_CTRL, &ctrl);

        if (atomic_read(&itv->capturing))
                ivtv_vapi(itv, CX2341X_ENC_MUTE_AUDIO, 1, 1);

        IVTV_DEBUG_INFO("Mute\n");
}

void ivtv_unmute(struct ivtv *itv)
{
        struct v4l2_control ctrl = { V4L2_CID_AUDIO_MUTE, 0 };

        /* initialize or refresh input */
        if (atomic_read(&itv->capturing) == 0)
                ivtv_vapi(itv, CX2341X_ENC_INITIALIZE_INPUT, 0);

        ivtv_sleep_timeout(HZ / 10, 0);

        if (atomic_read(&itv->capturing)) {
                ivtv_vapi(itv, CX2341X_ENC_MISC, 1, 12);
                ivtv_vapi(itv, CX2341X_ENC_MUTE_AUDIO, 1, 0);
        }

        /* Unmute */
        ivtv_control_ioctls(itv, VIDIOC_S_CTRL, &ctrl);
        IVTV_DEBUG_INFO("Unmute\n");
}