From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/usb/gadget/function/uvc_queue.c | 350 ++++++++++++++++++++++++++++++++ 1 file changed, 350 insertions(+) create mode 100644 drivers/usb/gadget/function/uvc_queue.c (limited to 'drivers/usb/gadget/function/uvc_queue.c') diff --git a/drivers/usb/gadget/function/uvc_queue.c b/drivers/usb/gadget/function/uvc_queue.c new file mode 100644 index 000000000..d617c39a0 --- /dev/null +++ b/drivers/usb/gadget/function/uvc_queue.c @@ -0,0 +1,350 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "uvc.h" + +/* ------------------------------------------------------------------------ + * Video buffers queue management. + * + * Video queues is initialized by uvcg_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_video *video = container_of(queue, struct uvc_video, queue); + + if (*nbuffers > UVC_MAX_VIDEO_BUFFERS) + *nbuffers = UVC_MAX_VIDEO_BUFFERS; + + *nplanes = 1; + + sizes[0] = video->imagesize; + + 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->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 struct vb2_ops uvc_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, +}; + +int uvcg_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type, + struct mutex *lock) +{ + int ret; + + queue->queue.type = type; + queue->queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF; + queue->queue.drv_priv = queue; + queue->queue.buf_struct_size = sizeof(struct uvc_buffer); + queue->queue.ops = &uvc_queue_qops; + queue->queue.lock = lock; + queue->queue.mem_ops = &vb2_vmalloc_memops; + queue->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC + | V4L2_BUF_FLAG_TSTAMP_SRC_EOF; + ret = vb2_queue_init(&queue->queue); + if (ret) + return ret; + + spin_lock_init(&queue->irqlock); + INIT_LIST_HEAD(&queue->irqqueue); + queue->flags = 0; + + return 0; +} + +/* + * Free the video buffers. + */ +void uvcg_free_buffers(struct uvc_video_queue *queue) +{ + vb2_queue_release(&queue->queue); +} + +/* + * Allocate the video buffers. + */ +int uvcg_alloc_buffers(struct uvc_video_queue *queue, + struct v4l2_requestbuffers *rb) +{ + int ret; + + ret = vb2_reqbufs(&queue->queue, rb); + + return ret ? ret : rb->count; +} + +int uvcg_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf) +{ + return vb2_querybuf(&queue->queue, buf); +} + +int uvcg_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf) +{ + unsigned long flags; + int ret; + + ret = vb2_qbuf(&queue->queue, buf); + if (ret < 0) + return ret; + + spin_lock_irqsave(&queue->irqlock, flags); + ret = (queue->flags & UVC_QUEUE_PAUSED) != 0; + queue->flags &= ~UVC_QUEUE_PAUSED; + spin_unlock_irqrestore(&queue->irqlock, flags); + return ret; +} + +/* + * Dequeue a video buffer. If nonblocking is false, block until a buffer is + * available. + */ +int uvcg_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf, + int nonblocking) +{ + return vb2_dqbuf(&queue->queue, buf, nonblocking); +} + +/* + * Poll the video queue. + * + * This function implements video queue polling and is intended to be used by + * the device poll handler. + */ +unsigned int uvcg_queue_poll(struct uvc_video_queue *queue, struct file *file, + poll_table *wait) +{ + return vb2_poll(&queue->queue, file, wait); +} + +int uvcg_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma) +{ + return vb2_mmap(&queue->queue, vma); +} + +#ifndef CONFIG_MMU +/* + * Get unmapped area. + * + * NO-MMU arch need this function to make mmap() work correctly. + */ +unsigned long uvcg_queue_get_unmapped_area(struct uvc_video_queue *queue, + unsigned long pgoff) +{ + return vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0); +} +#endif + +/* + * 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 uvcg_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_queue_buffer 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_DEV_DISCONNECTED + * state outside the queue code. + */ + if (disconnect) + queue->flags |= UVC_QUEUE_DISCONNECTED; + spin_unlock_irqrestore(&queue->irqlock, flags); +} + +/* + * 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 initializes parameters (such as sequence number, + * sync pattern, ...). If the queue is already enabled, return -EBUSY. + * + * 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 + * uvcg_queue_cancel() instead. + */ +int uvcg_queue_enable(struct uvc_video_queue *queue, int enable) +{ + unsigned long flags; + int ret = 0; + + if (enable) { + ret = vb2_streamon(&queue->queue, queue->queue.type); + if (ret < 0) + return ret; + + queue->sequence = 0; + queue->buf_used = 0; + } else { + ret = vb2_streamoff(&queue->queue, queue->queue.type); + if (ret < 0) + return ret; + + spin_lock_irqsave(&queue->irqlock, flags); + INIT_LIST_HEAD(&queue->irqqueue); + + /* + * FIXME: We need to clear the DISCONNECTED flag to ensure that + * applications will be able to queue buffers for the next + * streaming run. However, clearing it here doesn't guarantee + * that the device will be reconnected in the meantime. + */ + queue->flags &= ~UVC_QUEUE_DISCONNECTED; + spin_unlock_irqrestore(&queue->irqlock, flags); + } + + return ret; +} + +/* called with &queue_irqlock held.. */ +struct uvc_buffer *uvcg_queue_next_buffer(struct uvc_video_queue *queue, + struct uvc_buffer *buf) +{ + struct uvc_buffer *nextbuf; + + if ((queue->flags & UVC_QUEUE_DROP_INCOMPLETE) && + buf->length != buf->bytesused) { + buf->state = UVC_BUF_STATE_QUEUED; + vb2_set_plane_payload(&buf->buf, 0, 0); + return buf; + } + + list_del(&buf->queue); + if (!list_empty(&queue->irqqueue)) + nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer, + queue); + else + nextbuf = NULL; + + buf->buf.v4l2_buf.field = V4L2_FIELD_NONE; + buf->buf.v4l2_buf.sequence = queue->sequence++; + v4l2_get_timestamp(&buf->buf.v4l2_buf.timestamp); + + vb2_set_plane_payload(&buf->buf, 0, buf->bytesused); + vb2_buffer_done(&buf->buf, VB2_BUF_STATE_DONE); + + return nextbuf; +} + +struct uvc_buffer *uvcg_queue_head(struct uvc_video_queue *queue) +{ + struct uvc_buffer *buf = NULL; + + if (!list_empty(&queue->irqqueue)) + buf = list_first_entry(&queue->irqqueue, struct uvc_buffer, + queue); + else + queue->flags |= UVC_QUEUE_PAUSED; + + return buf; +} + -- cgit v1.2.3-54-g00ecf