OSCL-LXR linux-6.0.1/​drivers/​media/​usb/​uvc/​uvc_queue.c	Source navigation Diff markup Identifier search General search
	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *      uvc_queue.c  --  USB Video Class driver - Buffers management
  *
  *      Copyright (C) 2005-2010
  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
  */
 
 #include <linux/atomic.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/list.h>
 #include <linux/module.h>
 #include <linux/usb.h>
 #include <linux/videodev2.h>
 #include <linux/vmalloc.h>
 #include <linux/wait.h>
 #include <media/videobuf2-v4l2.h>
 #include <media/videobuf2-vmalloc.h>
 
 #include "uvcvideo.h"
 
 /* ------------------------------------------------------------------------
  * Video buffers queue management.
  *
  * Video queues is initialized by uvc_queue_init(). The function performs
  * basic initialization of the uvc_video_queue struct and never fails.
  *
  * Video buffers are managed by videobuf2. The driver uses a mutex to protect
  * the videobuf2 queue operations by serializing calls to videobuf2 and a
  * spinlock to protect the IRQ queue that holds the buffers to be processed by
  * the driver.
  */
 
 static inline struct uvc_buffer *uvc_vbuf_to_buffer(struct vb2_v4l2_buffer *buf)
 {
     return container_of(buf, struct uvc_buffer, buf);
 }
 
 /*
  * Return all queued buffers to videobuf2 in the requested state.
  *
  * This function must be called with the queue spinlock held.
  */
 static void uvc_queue_return_buffers(struct uvc_video_queue *queue,
                    enum uvc_buffer_state state)
 {
     enum vb2_buffer_state vb2_state = state == UVC_BUF_STATE_ERROR
                     ? VB2_BUF_STATE_ERROR
                     : VB2_BUF_STATE_QUEUED;
 
     while (!list_empty(&queue->irqqueue)) {
         struct uvc_buffer *buf = list_first_entry(&queue->irqqueue,
                               struct uvc_buffer,
                               queue);
         list_del(&buf->queue);
         buf->state = state;
         vb2_buffer_done(&buf->buf.vb2_buf, vb2_state);
     }
 }
 
 /* -----------------------------------------------------------------------------
  * videobuf2 queue operations
  */
 
 static int uvc_queue_setup(struct vb2_queue *vq,
                unsigned int *nbuffers, unsigned int *nplanes,
                unsigned int sizes[], struct device *alloc_devs[])
 {
     struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
     struct uvc_streaming *stream;
     unsigned int size;
 
     switch (vq->type) {
     case V4L2_BUF_TYPE_META_CAPTURE:
         size = UVC_METADATA_BUF_SIZE;
         break;
 
     default:
         stream = uvc_queue_to_stream(queue);
         size = stream->ctrl.dwMaxVideoFrameSize;
         break;
     }
 
     /*
      * When called with plane sizes, validate them. The driver supports
      * single planar formats only, and requires buffers to be large enough
      * to store a complete frame.
      */
     if (*nplanes)
         return *nplanes != 1 || sizes[0] < size ? -EINVAL : 0;
 
     *nplanes = 1;
     sizes[0] = size;
     return 0;
 }
 
 static int uvc_buffer_prepare(struct vb2_buffer *vb)
 {
     struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
     struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
     struct uvc_buffer *buf = uvc_vbuf_to_buffer(vbuf);
 
     if (vb->type == V4L2_BUF_TYPE_VIDEO_OUTPUT &&
         vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0)) {
         uvc_dbg(uvc_queue_to_stream(queue)->dev, CAPTURE,
             "[E] Bytes used out of bounds\n");
         return -EINVAL;
     }
 
     if (unlikely(queue->flags & UVC_QUEUE_DISCONNECTED))
         return -ENODEV;
 
     buf->state = UVC_BUF_STATE_QUEUED;
     buf->error = 0;
     buf->mem = vb2_plane_vaddr(vb, 0);
     buf->length = vb2_plane_size(vb, 0);
     if (vb->type != V4L2_BUF_TYPE_VIDEO_OUTPUT)
         buf->bytesused = 0;
     else
         buf->bytesused = vb2_get_plane_payload(vb, 0);
 
     return 0;
 }
 
 static void uvc_buffer_queue(struct vb2_buffer *vb)
 {
     struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
     struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
     struct uvc_buffer *buf = uvc_vbuf_to_buffer(vbuf);
     unsigned long flags;
 
     spin_lock_irqsave(&queue->irqlock, flags);
     if (likely(!(queue->flags & UVC_QUEUE_DISCONNECTED))) {
         kref_init(&buf->ref);
         list_add_tail(&buf->queue, &queue->irqqueue);
     } else {
         /*
          * If the device is disconnected return the buffer to userspace
          * directly. The next QBUF call will fail with -ENODEV.
          */
         buf->state = UVC_BUF_STATE_ERROR;
         vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
     }
 
     spin_unlock_irqrestore(&queue->irqlock, flags);
 }
 
 static void uvc_buffer_finish(struct vb2_buffer *vb)
 {
     struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
     struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
     struct uvc_streaming *stream = uvc_queue_to_stream(queue);
     struct uvc_buffer *buf = uvc_vbuf_to_buffer(vbuf);
 
     if (vb->state == VB2_BUF_STATE_DONE)
         uvc_video_clock_update(stream, vbuf, buf);
 }
 
 static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count)
 {
     struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
     struct uvc_streaming *stream = uvc_queue_to_stream(queue);
     int ret;
 
     lockdep_assert_irqs_enabled();
 
     queue->buf_used = 0;
 
     ret = uvc_video_start_streaming(stream);
     if (ret == 0)
         return 0;
 
     spin_lock_irq(&queue->irqlock);
     uvc_queue_return_buffers(queue, UVC_BUF_STATE_QUEUED);
     spin_unlock_irq(&queue->irqlock);
 
     return ret;
 }
 
 static void uvc_stop_streaming(struct vb2_queue *vq)
 {
     struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
 
     lockdep_assert_irqs_enabled();
 
     if (vq->type != V4L2_BUF_TYPE_META_CAPTURE)
         uvc_video_stop_streaming(uvc_queue_to_stream(queue));
 
     spin_lock_irq(&queue->irqlock);
     uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);
     spin_unlock_irq(&queue->irqlock);
 }
 
 static const struct vb2_ops uvc_queue_qops = {
     .queue_setup = uvc_queue_setup,
     .buf_prepare = uvc_buffer_prepare,
     .buf_queue = uvc_buffer_queue,
     .buf_finish = uvc_buffer_finish,
     .wait_prepare = vb2_ops_wait_prepare,
     .wait_finish = vb2_ops_wait_finish,
     .start_streaming = uvc_start_streaming,
     .stop_streaming = uvc_stop_streaming,
 };
 
 static const struct vb2_ops uvc_meta_queue_qops = {
     .queue_setup = uvc_queue_setup,
     .buf_prepare = uvc_buffer_prepare,
     .buf_queue = uvc_buffer_queue,
     .wait_prepare = vb2_ops_wait_prepare,
     .wait_finish = vb2_ops_wait_finish,
     .stop_streaming = uvc_stop_streaming,
 };
 
 int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
             int drop_corrupted)
 {
     int ret;
 
     queue->queue.type = type;
     queue->queue.io_modes = VB2_MMAP | VB2_USERPTR;
     queue->queue.drv_priv = queue;
     queue->queue.buf_struct_size = sizeof(struct uvc_buffer);
     queue->queue.mem_ops = &vb2_vmalloc_memops;
     queue->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC
         | V4L2_BUF_FLAG_TSTAMP_SRC_SOE;
     queue->queue.lock = &queue->mutex;
 
     switch (type) {
     case V4L2_BUF_TYPE_META_CAPTURE:
         queue->queue.ops = &uvc_meta_queue_qops;
         break;
     default:
         queue->queue.io_modes |= VB2_DMABUF;
         queue->queue.ops = &uvc_queue_qops;
         break;
     }
 
     ret = vb2_queue_init(&queue->queue);
     if (ret)
         return ret;
 
     mutex_init(&queue->mutex);
     spin_lock_init(&queue->irqlock);
     INIT_LIST_HEAD(&queue->irqqueue);
     queue->flags = drop_corrupted ? UVC_QUEUE_DROP_CORRUPTED : 0;
 
     return 0;
 }
 
 void uvc_queue_release(struct uvc_video_queue *queue)
 {
     mutex_lock(&queue->mutex);
     vb2_queue_release(&queue->queue);
     mutex_unlock(&queue->mutex);
 }
 
 /* -----------------------------------------------------------------------------
  * V4L2 queue operations
  */
 
 int uvc_request_buffers(struct uvc_video_queue *queue,
             struct v4l2_requestbuffers *rb)
 {
     int ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_reqbufs(&queue->queue, rb);
     mutex_unlock(&queue->mutex);
 
     return ret ? ret : rb->count;
 }
 
 int uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf)
 {
     int ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_querybuf(&queue->queue, buf);
     mutex_unlock(&queue->mutex);
 
     return ret;
 }
 
 int uvc_create_buffers(struct uvc_video_queue *queue,
                struct v4l2_create_buffers *cb)
 {
     int ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_create_bufs(&queue->queue, cb);
     mutex_unlock(&queue->mutex);
 
     return ret;
 }
 
 int uvc_queue_buffer(struct uvc_video_queue *queue,
              struct media_device *mdev, struct v4l2_buffer *buf)
 {
     int ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_qbuf(&queue->queue, mdev, buf);
     mutex_unlock(&queue->mutex);
 
     return ret;
 }
 
 int uvc_export_buffer(struct uvc_video_queue *queue,
               struct v4l2_exportbuffer *exp)
 {
     int ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_expbuf(&queue->queue, exp);
     mutex_unlock(&queue->mutex);
 
     return ret;
 }
 
 int uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf,
                int nonblocking)
 {
     int ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_dqbuf(&queue->queue, buf, nonblocking);
     mutex_unlock(&queue->mutex);
 
     return ret;
 }
 
 int uvc_queue_streamon(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 {
     int ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_streamon(&queue->queue, type);
     mutex_unlock(&queue->mutex);
 
     return ret;
 }
 
 int uvc_queue_streamoff(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 {
     int ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_streamoff(&queue->queue, type);
     mutex_unlock(&queue->mutex);
 
     return ret;
 }
 
 int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
 {
     return vb2_mmap(&queue->queue, vma);
 }
 
 #ifndef CONFIG_MMU
 unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
         unsigned long pgoff)
 {
     return vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0);
 }
 #endif
 
 __poll_t uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
                 poll_table *wait)
 {
     __poll_t ret;
 
     mutex_lock(&queue->mutex);
     ret = vb2_poll(&queue->queue, file, wait);
     mutex_unlock(&queue->mutex);
 
     return ret;
 }
 
 /* -----------------------------------------------------------------------------
  *
  */
 
 /*
  * Check if buffers have been allocated.
  */
 int uvc_queue_allocated(struct uvc_video_queue *queue)
 {
     int allocated;
 
     mutex_lock(&queue->mutex);
     allocated = vb2_is_busy(&queue->queue);
     mutex_unlock(&queue->mutex);
 
     return allocated;
 }
 
 /*
  * Cancel the video buffers queue.
  *
  * Cancelling the queue marks all buffers on the irq queue as erroneous,
  * wakes them up and removes them from the queue.
  *
  * If the disconnect parameter is set, further calls to uvc_queue_buffer will
  * fail with -ENODEV.
  *
  * This function acquires the irq spinlock and can be called from interrupt
  * context.
  */
 void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect)
 {
     unsigned long flags;
 
     spin_lock_irqsave(&queue->irqlock, flags);
     uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);
     /*
      * This must be protected by the irqlock spinlock to avoid race
      * conditions between uvc_buffer_queue and the disconnection event that
      * could result in an interruptible wait in uvc_dequeue_buffer. Do not
      * blindly replace this logic by checking for the UVC_QUEUE_DISCONNECTED
      * state outside the queue code.
      */
     if (disconnect)
         queue->flags |= UVC_QUEUE_DISCONNECTED;
     spin_unlock_irqrestore(&queue->irqlock, flags);
 }
 
 /*
  * uvc_queue_get_current_buffer: Obtain the current working output buffer
  *
  * Buffers may span multiple packets, and even URBs, therefore the active buffer
  * remains on the queue until the EOF marker.
  */
 static struct uvc_buffer *
 __uvc_queue_get_current_buffer(struct uvc_video_queue *queue)
 {
     if (list_empty(&queue->irqqueue))
         return NULL;
 
     return list_first_entry(&queue->irqqueue, struct uvc_buffer, queue);
 }
 
 struct uvc_buffer *uvc_queue_get_current_buffer(struct uvc_video_queue *queue)
 {
     struct uvc_buffer *nextbuf;
     unsigned long flags;
 
     spin_lock_irqsave(&queue->irqlock, flags);
     nextbuf = __uvc_queue_get_current_buffer(queue);
     spin_unlock_irqrestore(&queue->irqlock, flags);
 
     return nextbuf;
 }
 
 /*
  * uvc_queue_buffer_requeue: Requeue a buffer on our internal irqqueue
  *
  * Reuse a buffer through our internal queue without the need to 'prepare'.
  * The buffer will be returned to userspace through the uvc_buffer_queue call if
  * the device has been disconnected.
  */
 static void uvc_queue_buffer_requeue(struct uvc_video_queue *queue,
         struct uvc_buffer *buf)
 {
     buf->error = 0;
     buf->state = UVC_BUF_STATE_QUEUED;
     buf->bytesused = 0;
     vb2_set_plane_payload(&buf->buf.vb2_buf, 0, 0);
 
     uvc_buffer_queue(&buf->buf.vb2_buf);
 }
 
 static void uvc_queue_buffer_complete(struct kref *ref)
 {
     struct uvc_buffer *buf = container_of(ref, struct uvc_buffer, ref);
     struct vb2_buffer *vb = &buf->buf.vb2_buf;
     struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
 
     if ((queue->flags & UVC_QUEUE_DROP_CORRUPTED) && buf->error) {
         uvc_queue_buffer_requeue(queue, buf);
         return;
     }
 
     buf->state = buf->error ? UVC_BUF_STATE_ERROR : UVC_BUF_STATE_DONE;
     vb2_set_plane_payload(&buf->buf.vb2_buf, 0, buf->bytesused);
     vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_DONE);
 }
 
 /*
  * Release a reference on the buffer. Complete the buffer when the last
  * reference is released.
  */
 void uvc_queue_buffer_release(struct uvc_buffer *buf)
 {
     kref_put(&buf->ref, uvc_queue_buffer_complete);
 }
 
 /*
  * Remove this buffer from the queue. Lifetime will persist while async actions
  * are still running (if any), and uvc_queue_buffer_release will give the buffer
  * back to VB2 when all users have completed.
  */
 struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
         struct uvc_buffer *buf)
 {
     struct uvc_buffer *nextbuf;
     unsigned long flags;
 
     spin_lock_irqsave(&queue->irqlock, flags);
     list_del(&buf->queue);
     nextbuf = __uvc_queue_get_current_buffer(queue);
     spin_unlock_irqrestore(&queue->irqlock, flags);
 
     uvc_queue_buffer_release(buf);
 
     return nextbuf;
 }

This page was automatically generated by the 2.1.0 LXR engine. The LXR team