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author | Mauro Carvalho Chehab <mchehab@redhat.com> | 2012-08-14 00:13:22 -0300 |
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committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2012-08-15 16:25:07 -0300 |
commit | 0c0d06cac63ee327ceaab4b5ffe2206574ab86bd (patch) | |
tree | e759f0dc3185d97f2a0c6b5cd5e32ea6faa74d40 /drivers/media/usb/uvc/uvc_queue.c | |
parent | 84cfe9e79bd5ac11c963f4841158454fefa872f6 (diff) | |
download | linux-0c0d06cac63ee327ceaab4b5ffe2206574ab86bd.tar.gz linux-0c0d06cac63ee327ceaab4b5ffe2206574ab86bd.tar.bz2 linux-0c0d06cac63ee327ceaab4b5ffe2206574ab86bd.zip |
[media] rename most media/video usb drivers to media/usb
Rename all USB drivers with their own directory under
drivers/media/video into drivers/media/usb and update the
building system.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/usb/uvc/uvc_queue.c')
-rw-r--r-- | drivers/media/usb/uvc/uvc_queue.c | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c new file mode 100644 index 000000000000..9288fbd5001b --- /dev/null +++ b/drivers/media/usb/uvc/uvc_queue.c @@ -0,0 +1,359 @@ +/* + * uvc_queue.c -- USB Video Class driver - Buffers management + * + * Copyright (C) 2005-2010 + * Laurent Pinchart (laurent.pinchart@ideasonboard.com) + * + * 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. + * + */ + +#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-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. + */ + +/* ----------------------------------------------------------------------------- + * videobuf2 queue operations + */ + +static int uvc_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt, + unsigned int *nbuffers, unsigned int *nplanes, + unsigned int sizes[], void *alloc_ctxs[]) +{ + struct uvc_video_queue *queue = vb2_get_drv_priv(vq); + struct uvc_streaming *stream = + container_of(queue, struct uvc_streaming, queue); + + if (*nbuffers > UVC_MAX_VIDEO_BUFFERS) + *nbuffers = UVC_MAX_VIDEO_BUFFERS; + + *nplanes = 1; + + sizes[0] = stream->ctrl.dwMaxVideoFrameSize; + + return 0; +} + +static int uvc_buffer_prepare(struct vb2_buffer *vb) +{ + struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); + struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); + + if (vb->v4l2_buf.type == V4L2_BUF_TYPE_VIDEO_OUTPUT && + vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0)) { + uvc_trace(UVC_TRACE_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->v4l2_buf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE) + buf->bytesused = 0; + else + buf->bytesused = vb2_get_plane_payload(vb, 0); + + return 0; +} + +static void uvc_buffer_queue(struct vb2_buffer *vb) +{ + struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); + struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); + unsigned long flags; + + spin_lock_irqsave(&queue->irqlock, flags); + if (likely(!(queue->flags & UVC_QUEUE_DISCONNECTED))) { + 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(&buf->buf, VB2_BUF_STATE_ERROR); + } + + spin_unlock_irqrestore(&queue->irqlock, flags); +} + +static int uvc_buffer_finish(struct vb2_buffer *vb) +{ + struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); + struct uvc_streaming *stream = + container_of(queue, struct uvc_streaming, queue); + struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); + + uvc_video_clock_update(stream, &vb->v4l2_buf, buf); + return 0; +} + +static 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, +}; + +void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type, + int drop_corrupted) +{ + 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.ops = &uvc_queue_qops; + queue->queue.mem_ops = &vb2_vmalloc_memops; + vb2_queue_init(&queue->queue); + + mutex_init(&queue->mutex); + spin_lock_init(&queue->irqlock); + INIT_LIST_HEAD(&queue->irqqueue); + queue->flags = drop_corrupted ? UVC_QUEUE_DROP_CORRUPTED : 0; +} + +/* ----------------------------------------------------------------------------- + * V4L2 queue operations + */ + +int uvc_alloc_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; +} + +void uvc_free_buffers(struct uvc_video_queue *queue) +{ + mutex_lock(&queue->mutex); + vb2_queue_release(&queue->queue); + mutex_unlock(&queue->mutex); +} + +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_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf) +{ + int ret; + + mutex_lock(&queue->mutex); + ret = vb2_qbuf(&queue->queue, buf); + 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_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma) +{ + int ret; + + mutex_lock(&queue->mutex); + ret = vb2_mmap(&queue->queue, vma); + mutex_unlock(&queue->mutex); + + return ret; +} + +#ifndef CONFIG_MMU +unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue, + unsigned long pgoff) +{ + unsigned long ret; + + mutex_lock(&queue->mutex); + ret = vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0); + mutex_unlock(&queue->mutex); + return ret; +} +#endif + +unsigned int uvc_queue_poll(struct uvc_video_queue *queue, struct file *file, + poll_table *wait) +{ + unsigned int 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; +} + +/* + * Enable or disable the video buffers queue. + * + * The queue must be enabled before starting video acquisition and must be + * disabled after stopping it. This ensures that the video buffers queue + * state can be properly initialized before buffers are accessed from the + * interrupt handler. + * + * Enabling the video queue returns -EBUSY if the queue is already enabled. + * + * Disabling the video queue cancels the queue and removes all buffers from + * the main queue. + * + * This function can't be called from interrupt context. Use + * uvc_queue_cancel() instead. + */ +int uvc_queue_enable(struct uvc_video_queue *queue, int enable) +{ + unsigned long flags; + int ret; + + mutex_lock(&queue->mutex); + if (enable) { + ret = vb2_streamon(&queue->queue, queue->queue.type); + if (ret < 0) + goto done; + + queue->buf_used = 0; + } else { + ret = vb2_streamoff(&queue->queue, queue->queue.type); + if (ret < 0) + goto done; + + spin_lock_irqsave(&queue->irqlock, flags); + INIT_LIST_HEAD(&queue->irqqueue); + spin_unlock_irqrestore(&queue->irqlock, flags); + } + +done: + mutex_unlock(&queue->mutex); + return ret; +} + +/* + * 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) +{ + struct uvc_buffer *buf; + unsigned long flags; + + spin_lock_irqsave(&queue->irqlock, flags); + while (!list_empty(&queue->irqqueue)) { + buf = list_first_entry(&queue->irqqueue, struct uvc_buffer, + queue); + list_del(&buf->queue); + buf->state = UVC_BUF_STATE_ERROR; + vb2_buffer_done(&buf->buf, VB2_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); +} + +struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue, + struct uvc_buffer *buf) +{ + struct uvc_buffer *nextbuf; + unsigned long flags; + + if ((queue->flags & UVC_QUEUE_DROP_CORRUPTED) && buf->error) { + buf->error = 0; + buf->state = UVC_BUF_STATE_QUEUED; + vb2_set_plane_payload(&buf->buf, 0, 0); + return buf; + } + + spin_lock_irqsave(&queue->irqlock, flags); + list_del(&buf->queue); + if (!list_empty(&queue->irqqueue)) + nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer, + queue); + else + nextbuf = NULL; + spin_unlock_irqrestore(&queue->irqlock, flags); + + buf->state = buf->error ? VB2_BUF_STATE_ERROR : UVC_BUF_STATE_DONE; + vb2_set_plane_payload(&buf->buf, 0, buf->bytesused); + vb2_buffer_done(&buf->buf, VB2_BUF_STATE_DONE); + + return nextbuf; +} |