V4L/DVB (4929): Read() implementation + format set/get simplifications

- implement read() entry point that works with linux list.h
- rework of VIDIOC_ENUM_FMT/VIDIOC_S_FMT/VIDIOC_G_FMT
- VIDIOC_STREAMON : allows streaming whereas there is no queued buffer
(xdtv does VIDIOC_STREAMON before VIDIOC_QBUFs)

Signed-off-by: Thierry MERLE <thierry.merle@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 167 insertions, 156 deletions

diff --git a/drivers/media/video/usbvision/usbvision-core.c b/drivers/media/video/usbvision/usbvision-core.c
index 5a61ed728b35..3833f3fbbdf0 100644
--- a/drivers/media/video/usbvision/usbvision-core.c
+++ b/drivers/media/video/usbvision/usbvision-core.c
@@ -409,7 +409,8 @@
 
 
 static int usbvision_nr = 0;                    // sequential number of usbvision device
-
+static unsigned long usbvision_timestamp = 0;           // timestamp in jiffies of a hundred frame
+static unsigned long usbvision_counter = 0;             // frame counter
 
 static const int max_imgwidth = MAX_FRAME_WIDTH;
 static const int max_imgheight = MAX_FRAME_HEIGHT;
@@ -4278,6 +4279,7 @@ static int usbvision_v4l2_do_ioctl(struct inode *inode, struct file *file,
                         list_add_tail(&usbvision->frame[vb->index].frame, &usbvision->inqueue);
                         spin_unlock_irqrestore(&usbvision->queue_lock, lock_flags);
 
+                        PDEBUG(DBG_IOCTL, "VIDIOC_QBUF frame #%d",vb->index);
                         return 0;
                 }
                 case VIDIOC_DQBUF:
@@ -4312,18 +4314,31 @@ static int usbvision_v4l2_do_ioctl(struct inode *inode, struct file *file,
                         vb->flags = V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | V4L2_BUF_FLAG_DONE;
                         vb->index = f->index;
                         vb->sequence = f->sequence;
+                        vb->timestamp = f->timestamp;
+                        vb->field = V4L2_FIELD_NONE;
+                        vb->bytesused = f->scanlength;
 
+                        if(debug & DBG_IOCTL) { // do not spend computing time for debug stuff if not needed !
+                                if(usbvision_counter == 100) {
+                                        PDEBUG(DBG_IOCTL, "VIDIOC_DQBUF delta=%d",(unsigned)(jiffies-usbvision_timestamp));
+                                        usbvision_counter = 0;
+                                        usbvision_timestamp = jiffies;
+                                }
+                                else {
+                                        usbvision_counter++;
+                                }
+                                PDEBUG(DBG_IOCTL, "VIDIOC_DQBUF frame #%d",vb->index);
+                        }
                         return 0;
                 }
                 case VIDIOC_STREAMON:
                 {
                         int b=V4L2_BUF_TYPE_VIDEO_CAPTURE;
 
-                        if (list_empty(&usbvision->inqueue))
-                                return -EINVAL;
-
                         usbvision->streaming = Stream_On;
 
+                        if(debug & DBG_IOCTL) usbvision_timestamp = jiffies;
+
                         call_i2c_clients(usbvision,VIDIOC_STREAMON , &b);
 
                         PDEBUG(DBG_IOCTL, "VIDIOC_STREAMON");
@@ -4412,134 +4427,132 @@ static int usbvision_v4l2_do_ioctl(struct inode *inode, struct file *file,
                 {
                         struct v4l2_fmtdesc *vfd = arg;
 
-                        if ( (dga == 0) &&
-                             (vfd->type == V4L2_BUF_TYPE_VIDEO_OVERLAY) &&
-                             (usbvision->palette.format != V4L2_PIX_FMT_YVU420) &&
-                             (usbvision->palette.format != V4L2_PIX_FMT_YUV422P) ) {
-                                return -EINVAL;
-                        }
                         if(vfd->index>=USBVISION_SUPPORTED_PALETTES-1) {
                                 return -EINVAL;
                         }
                         vfd->flags = 0;
+                        vfd->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
                         strcpy(vfd->description,usbvision_v4l2_format[vfd->index].desc);
                         vfd->pixelformat = usbvision_v4l2_format[vfd->index].format;
+                        memset(vfd->reserved, 0, sizeof(vfd->reserved));
                         return 0;
                 }
                 case VIDIOC_G_FMT:
                 {
                         struct v4l2_format *vf = arg;
 
-                        if ( (dga == 0) &&
-                             (vf->type == V4L2_BUF_TYPE_VIDEO_OVERLAY) &&
-                             (usbvision->palette.format != V4L2_PIX_FMT_YVU420) &&
-                             (usbvision->palette.format != V4L2_PIX_FMT_YUV422P) ) {
-                                return -EINVAL;
+                        switch (vf->type) {
+                                case V4L2_BUF_TYPE_VIDEO_CAPTURE:
+                                {
+                                        vf->fmt.pix.width = usbvision->curwidth;
+                                        vf->fmt.pix.height = usbvision->curheight;
+                                        vf->fmt.pix.pixelformat = usbvision->palette.format;
+                                        vf->fmt.pix.bytesperline =  usbvision->curwidth*usbvision->palette.bytes_per_pixel;
+                                        vf->fmt.pix.sizeimage = vf->fmt.pix.bytesperline*usbvision->curheight;
+                                        vf->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
+                                        vf->fmt.pix.field = V4L2_FIELD_NONE; /* Always progressive image */
+                                }
+                                return 0;
+                                default:
+                                        PDEBUG(DBG_IOCTL, "VIDIOC_G_FMT invalid type %d",vf->type);
+                                        return -EINVAL;
                         }
-                        down(&usbvision->lock);
-                        *vf = usbvision->vid_win;
-                        up(&usbvision->lock);
-                        PDEBUG(DBG_IOCTL, "VIDIOC_G_FMT x=%d, y=%d, w=%d, h=%d, chroma=%x, clips=%d",
-                               vf->fmt.win.w.left, vf->fmt.win.w.top, vf->fmt.win.w.width, vf->fmt.win.w.height, vf->fmt.win.chromakey, vf->fmt.win.clipcount);
+                        PDEBUG(DBG_IOCTL, "VIDIOC_G_FMT w=%d, h=%d",vf->fmt.win.w.width, vf->fmt.win.w.height);
                         return 0;
                 }
+                case VIDIOC_TRY_FMT:
                 case VIDIOC_S_FMT:
                 {
                         struct v4l2_format *vf = arg;
                         struct v4l2_clip *vc=NULL;
                         int on,formatIdx;
 
-                        if ( (dga == 0) &&
-                             (vf->type == V4L2_BUF_TYPE_VIDEO_OVERLAY) &&
-                             (usbvision->palette.format != V4L2_PIX_FMT_YVU420) &&
-                             (usbvision->palette.format != V4L2_PIX_FMT_YUV422P) ) {
-                                return -EINVAL;
-                        }
-                        if(vf->type == V4L2_BUF_TYPE_VIDEO_OVERLAY) {
-                                if (vf->fmt.win.clipcount>256) {
-                                        return -EDOM;   /* Too many clips! */
-                                }
-                                // Do every clips.
-                                vc = vmalloc(sizeof(struct v4l2_clip)*(vf->fmt.win.clipcount+4));
-                                if (vc == NULL) {
-                                        return -ENOMEM;
-                                }
-                                if (vf->fmt.win.clipcount && copy_from_user(vc,vf->fmt.win.clips,sizeof(struct v4l2_clip)*vf->fmt.win.clipcount)) {
-                                        return -EFAULT;
-                                }
-                                on = usbvision->overlay;        // Save overlay state
-                                if (on) {
-                                        usbvision_cap(usbvision, 0);
-                                }
+                        switch(vf->type) {
+                                case V4L2_BUF_TYPE_VIDEO_OVERLAY:
+                                {
+                                        if (vf->fmt.win.clipcount>256) {
+                                                return -EDOM;   /* Too many clips! */
+                                        }
+                                        // Do every clips.
+                                        vc = vmalloc(sizeof(struct v4l2_clip)*(vf->fmt.win.clipcount+4));
+                                        if (vc == NULL) {
+                                                return -ENOMEM;
+                                        }
+                                        if (vf->fmt.win.clipcount && copy_from_user(vc,vf->fmt.win.clips,sizeof(struct v4l2_clip)*vf->fmt.win.clipcount)) {
+                                                return -EFAULT;
+                                        }
+                                        on = usbvision->overlay;        // Save overlay state
+                                        if (on) {
+                                                usbvision_cap(usbvision, 0);
+                                        }
 
-                                // strange, it seems xawtv sometimes calls us with 0
-                                // width and/or height. Ignore these values
-                                if (vf->fmt.win.w.left == 0) {
-                                        vf->fmt.win.w.left = usbvision->vid_win.fmt.win.w.left;
-                                }
-                                if (vf->fmt.win.w.top == 0) {
-                                        vf->fmt.win.w.top = usbvision->vid_win.fmt.win.w.top;
-                                }
+                                        // strange, it seems xawtv sometimes calls us with 0
+                                        // width and/or height. Ignore these values
+                                        if (vf->fmt.win.w.left == 0) {
+                                                vf->fmt.win.w.left = usbvision->vid_win.fmt.win.w.left;
+                                        }
+                                        if (vf->fmt.win.w.top == 0) {
+                                                vf->fmt.win.w.top = usbvision->vid_win.fmt.win.w.top;
+                                        }
 
-                                // by now we are committed to the new data...
-                                down(&usbvision->lock);
-                                RESTRICT_TO_RANGE(vf->fmt.win.w.width, MIN_FRAME_WIDTH, MAX_FRAME_WIDTH);
-                                RESTRICT_TO_RANGE(vf->fmt.win.w.height, MIN_FRAME_HEIGHT, MAX_FRAME_HEIGHT);
-                                usbvision->vid_win = *vf;
-                                usbvision->overlay_frame.width = vf->fmt.win.w.width;
-                                usbvision->overlay_frame.height = vf->fmt.win.w.height;
-                                usbvision_set_output(usbvision, vf->fmt.win.w.width, vf->fmt.win.w.height);
-                                up(&usbvision->lock);
-
-                                // Impose display clips
-                                if (vf->fmt.win.w.left+vf->fmt.win.w.width > (unsigned int)usbvision->vid_buf.fmt.width) {
-                                        usbvision_new_clip(vf, vc, usbvision->vid_buf.fmt.width-vf->fmt.win.w.left, 0, vf->fmt.win.w.width-1, vf->fmt.win.w.height-1);
-                                }
-                                if (vf->fmt.win.w.top+vf->fmt.win.w.height > (unsigned int)usbvision->vid_buf.fmt.height) {
-                                        usbvision_new_clip(vf, vc, 0, usbvision->vid_buf.fmt.height-vf->fmt.win.w.top, vf->fmt.win.w.width-1, vf->fmt.win.w.height-1);
-                                }
+                                        // by now we are committed to the new data...
+                                        down(&usbvision->lock);
+                                        RESTRICT_TO_RANGE(vf->fmt.win.w.width, MIN_FRAME_WIDTH, MAX_FRAME_WIDTH);
+                                        RESTRICT_TO_RANGE(vf->fmt.win.w.height, MIN_FRAME_HEIGHT, MAX_FRAME_HEIGHT);
+                                        usbvision->vid_win = *vf;
+                                        usbvision->overlay_frame.width = vf->fmt.win.w.width;
+                                        usbvision->overlay_frame.height = vf->fmt.win.w.height;
+                                        usbvision_set_output(usbvision, vf->fmt.win.w.width, vf->fmt.win.w.height);
+                                        up(&usbvision->lock);
+
+                                        // Impose display clips
+                                        if (vf->fmt.win.w.left+vf->fmt.win.w.width > (unsigned int)usbvision->vid_buf.fmt.width) {
+                                                usbvision_new_clip(vf, vc, usbvision->vid_buf.fmt.width-vf->fmt.win.w.left, 0, vf->fmt.win.w.width-1, vf->fmt.win.w.height-1);
+                                        }
+                                        if (vf->fmt.win.w.top+vf->fmt.win.w.height > (unsigned int)usbvision->vid_buf.fmt.height) {
+                                                usbvision_new_clip(vf, vc, 0, usbvision->vid_buf.fmt.height-vf->fmt.win.w.top, vf->fmt.win.w.width-1, vf->fmt.win.w.height-1);
+                                        }
 
-                                // built the requested clipping zones
-                                usbvision_built_overlay(usbvision, vf->fmt.win.clipcount, vc);
-                                vfree(vc);
+                                        // built the requested clipping zones
+                                        usbvision_built_overlay(usbvision, vf->fmt.win.clipcount, vc);
+                                        vfree(vc);
 
-                                // restore overlay state
-                                if (on) {
-                                        usbvision_cap(usbvision, 1);
+                                        // restore overlay state
+                                        if (on) {
+                                                usbvision_cap(usbvision, 1);
+                                        }
+                                        usbvision->vid_win_valid = 1;
+                                        PDEBUG(DBG_IOCTL, "VIDIOC_S_FMT overlay x=%d, y=%d, w=%d, h=%d, chroma=%x, clips=%d",
+                                               vf->fmt.win.w.left, vf->fmt.win.w.top, vf->fmt.win.w.width, vf->fmt.win.w.height, vf->fmt.win.chromakey, vf->fmt.win.clipcount);
+                                        return 0;
                                 }
-                                usbvision->vid_win_valid = 1;
-                                PDEBUG(DBG_IOCTL, "VIDIOC_S_FMT overlay x=%d, y=%d, w=%d, h=%d, chroma=%x, clips=%d",
-                                       vf->fmt.win.w.left, vf->fmt.win.w.top, vf->fmt.win.w.width, vf->fmt.win.w.height, vf->fmt.win.chromakey, vf->fmt.win.clipcount);
-                        }
-                        else {
-                                /* Find requested format in available ones */
-                                for(formatIdx=0;formatIdx<USBVISION_SUPPORTED_PALETTES;formatIdx++) {
-                                        if(vf->fmt.pix.pixelformat == usbvision_v4l2_format[formatIdx].format) {
-                                                usbvision->palette = usbvision_v4l2_format[formatIdx];
-                                                break;
+                                case V4L2_BUF_TYPE_VIDEO_CAPTURE:
+                                {
+                                        /* Find requested format in available ones */
+                                        for(formatIdx=0;formatIdx<USBVISION_SUPPORTED_PALETTES;formatIdx++) {
+                                                if(vf->fmt.pix.pixelformat == usbvision_v4l2_format[formatIdx].format) {
+                                                        usbvision->palette = usbvision_v4l2_format[formatIdx];
+                                                        break;
+                                                }
+                                        }
+                                        /* robustness */
+                                        if(formatIdx == USBVISION_SUPPORTED_PALETTES) {
+                                                return -EINVAL;
                                         }
+                                        RESTRICT_TO_RANGE(vf->fmt.pix.width, MIN_FRAME_WIDTH, MAX_FRAME_WIDTH);
+                                        RESTRICT_TO_RANGE(vf->fmt.pix.height, MIN_FRAME_HEIGHT, MAX_FRAME_HEIGHT);
+                                        // by now we are committed to the new data...
+                                        down(&usbvision->lock);
+                                        usbvision_set_output(usbvision, vf->fmt.pix.width, vf->fmt.pix.height);
+                                        up(&usbvision->lock);
+
+                                        PDEBUG(DBG_IOCTL, "VIDIOC_S_FMT grabdisplay w=%d, h=%d, format=%s",
+                                               vf->fmt.pix.width, vf->fmt.pix.height,usbvision->palette.desc);
+                                        return 0;
                                 }
-                                /* robustness */
-                                if(formatIdx == USBVISION_SUPPORTED_PALETTES) {
+                                default:
                                         return -EINVAL;
-                                }
-                                usbvision->vid_win.fmt.pix.pixelformat = vf->fmt.pix.pixelformat;
-                                usbvision->vid_win.fmt.pix.width = vf->fmt.pix.width; //Image width in pixels.
-                                usbvision->vid_win.fmt.pix.height = vf->fmt.pix.height; // Image height in pixels.
-
-                                // by now we are committed to the new data...
-                                down(&usbvision->lock);
-                                RESTRICT_TO_RANGE(vf->fmt.pix.width, MIN_FRAME_WIDTH, MAX_FRAME_WIDTH);
-                                RESTRICT_TO_RANGE(vf->fmt.pix.height, MIN_FRAME_HEIGHT, MAX_FRAME_HEIGHT);
-                                usbvision->vid_win = *vf;
-                                usbvision_set_output(usbvision, vf->fmt.pix.width, vf->fmt.pix.height);
-                                up(&usbvision->lock);
-
-                                usbvision->vid_win_valid = 1;
-                                PDEBUG(DBG_IOCTL, "VIDIOC_S_FMT grabdisplay w=%d, h=%d, ",
-                                       vf->fmt.pix.width, vf->fmt.pix.height);
                         }
-                        return 0;
                 }
                 case VIDIOC_OVERLAY:
                 {
@@ -4586,99 +4599,97 @@ static ssize_t usbvision_v4l2_read(struct file *file, char *buf,
         struct video_device *dev = video_devdata(file);
         struct usb_usbvision *usbvision = (struct usb_usbvision *) video_get_drvdata(dev);
         int noblock = file->f_flags & O_NONBLOCK;
+        unsigned long lock_flags;
 
         int frmx = -1;
-        int rc = 0;
+        int ret,i;
         struct usbvision_frame *frame;
-return -EINVAL;
+
         PDEBUG(DBG_IO, "%s: %ld bytes, noblock=%d", __FUNCTION__, (unsigned long)count, noblock);
 
         if (!USBVISION_IS_OPERATIONAL(usbvision) || (buf == NULL))
                 return -EFAULT;
 
-        down(&usbvision->lock);
-        //code for testing compression
-        if (usbvision->isocMode == ISOC_MODE_COMPRESS) {
-          usbvision->frame[0].v4l2_format = usbvision_v4l2_format[0]; //V4L2_PIX_FMT_GREY;
-          usbvision->frame[1].v4l2_format = usbvision_v4l2_format[0]; // V4L2_PIX_FMT_GREY;
-        }
+        /* no stream is running, make it running ! */
+        usbvision->streaming = Stream_On;
+        call_i2c_clients(usbvision,VIDIOC_STREAMON , NULL);
 
-        // See if a frame is completed, then use it.
-        if (usbvision->frame[0].grabstate >= FrameState_Done) // _Done or _Error
-                frmx = 0;
-        else if (usbvision->frame[1].grabstate >= FrameState_Done)// _Done or _Error
-                frmx = 1;
+        /* First, enqueue as many frames as possible (like a user of VIDIOC_QBUF would do) */
+        for(i=0;i<USBVISION_NUMFRAMES;i++) {
+                frame = &usbvision->frame[i];
+                if(frame->grabstate == FrameState_Unused) {
+                        /* Mark it as ready and enqueue frame */
+                        frame->grabstate = FrameState_Ready;
+                        frame->scanstate = ScanState_Scanning;
+                        frame->scanlength = 0;  /* Accumulated in usbvision_parse_data() */
 
-        if (noblock && (frmx == -1)) {
-                count = -EAGAIN;
-                goto usbvision_v4l2_read_done;
-        }
+                        /* set v4l2_format index */
+                        frame->v4l2_format = usbvision->palette;
 
-        // If no FRAME_DONE, look for a FRAME_GRABBING state.
-        // See if a frame is in process (grabbing), then use it.
-        if (frmx == -1) {
-                if (usbvision->frame[0].grabstate == FrameState_Grabbing)
-                        frmx = 0;
-                else if (usbvision->frame[1].grabstate == FrameState_Grabbing)
-                        frmx = 1;
+                        spin_lock_irqsave(&usbvision->queue_lock, lock_flags);
+                        list_add_tail(&frame->frame, &usbvision->inqueue);
+                        spin_unlock_irqrestore(&usbvision->queue_lock, lock_flags);
+                }
         }
 
-        // If no frame is active, start one.
-        if (frmx == -1)
-        // FIXME: enqueue all inqueue...
-        /*              usbvision_new_frame(usbvision, frmx = 0); */
-
-        frame = &usbvision->frame[frmx];
+        /* Then try to steal a frame (like a VIDIOC_DQBUF would do) */
+        if (list_empty(&(usbvision->outqueue))) {
+                if(noblock)
+                        return -EAGAIN;
 
-      restart:
-        if (!USBVISION_IS_OPERATIONAL(usbvision)) {
-                count = -EIO;
-                goto usbvision_v4l2_read_done;
+                ret = wait_event_interruptible
+                        (usbvision->wait_frame,
+                         !list_empty(&(usbvision->outqueue)));
+                if (ret)
+                        return ret;
         }
-        PDEBUG(DBG_IO, "Waiting frame grabbing");
-        rc = wait_event_interruptible(usbvision->wait_frame, (frame->grabstate == FrameState_Done) ||
-                                                 (frame->grabstate == FrameState_Error));
-        if (rc) {
-                goto usbvision_v4l2_read_done;
+
+        spin_lock_irqsave(&usbvision->queue_lock, lock_flags);
+        frame = list_entry(usbvision->outqueue.next,
+                           struct usbvision_frame, frame);
+        list_del(usbvision->outqueue.next);
+        spin_unlock_irqrestore(&usbvision->queue_lock, lock_flags);
+
+        if(debug & DBG_IOCTL) { // do not spend computing time for debug stuff if not needed !
+                if(usbvision_counter == 100) {
+                        PDEBUG(DBG_IOCTL, "VIDIOC_DQBUF delta=%d",(unsigned)(jiffies-usbvision_timestamp));
+                        usbvision_counter = 0;
+                        usbvision_timestamp = jiffies;
+                }
+                else {
+                        usbvision_counter++;
+                }
         }
 
+        /* An error returns an empty frame */
         if (frame->grabstate == FrameState_Error) {
                 frame->bytes_read = 0;
-                // FIXME: enqueue all inqueue...
-/*              if (usbvision_new_frame(usbvision, frmx)) { */
-/*                      err("%s: usbvision_new_frame() failed", __FUNCTION__); */
-/*              } */
-                goto restart;
+                return 0;
         }
 
         PDEBUG(DBG_IO, "%s: frmx=%d, bytes_read=%ld, scanlength=%ld", __FUNCTION__,
-                       frmx, frame->bytes_read, frame->scanlength);
+                       frame->index, frame->bytes_read, frame->scanlength);
 
         /* copy bytes to user space; we allow for partials reads */
         if ((count + frame->bytes_read) > (unsigned long)frame->scanlength)
                 count = frame->scanlength - frame->bytes_read;
 
         if (copy_to_user(buf, frame->data + frame->bytes_read, count)) {
-                count = -EFAULT;
-                goto usbvision_v4l2_read_done;
+                return -EFAULT;
         }
 
         frame->bytes_read += count;
         PDEBUG(DBG_IO, "%s: {copy} count used=%ld, new bytes_read=%ld", __FUNCTION__,
                        (unsigned long)count, frame->bytes_read);
 
-        if (frame->bytes_read >= frame->scanlength) {// All data has been read
+        // For now, forget the frame if it has not been read in one shot.
+/*      if (frame->bytes_read >= frame->scanlength) {// All data has been read */
                 frame->bytes_read = 0;
 
                 /* Mark it as available to be used again. */
                 usbvision->frame[frmx].grabstate = FrameState_Unused;
-                // FIXME enqueue another frame
-/*              if (usbvision_new_frame(usbvision, frmx ? 0 : 1)) */
-/*                      err("%s: usbvision_new_frame() failed", __FUNCTION__); */
-        }
+/*      } */
 
-usbvision_v4l2_read_done:
-        up(&usbvision->lock);
         return count;
 }