diff options
Diffstat (limited to 'drivers/usb/gadget/uvc_queue.c')
-rw-r--r-- | drivers/usb/gadget/uvc_queue.c | 538 |
1 files changed, 171 insertions, 367 deletions
diff --git a/drivers/usb/gadget/uvc_queue.c b/drivers/usb/gadget/uvc_queue.c index 104ae9c..7ce27e3 100644 --- a/drivers/usb/gadget/uvc_queue.c +++ b/drivers/usb/gadget/uvc_queue.c @@ -10,6 +10,7 @@ * (at your option) any later version. */ +#include <linux/atomic.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/list.h> @@ -18,7 +19,8 @@ #include <linux/videodev2.h> #include <linux/vmalloc.h> #include <linux/wait.h> -#include <linux/atomic.h> + +#include <media/videobuf2-vmalloc.h> #include "uvc.h" @@ -28,330 +30,175 @@ * Video queues is initialized by uvc_queue_init(). The function performs * basic initialization of the uvc_video_queue struct and never fails. * - * Video buffer allocation and freeing are performed by uvc_alloc_buffers and - * uvc_free_buffers respectively. The former acquires the video queue lock, - * while the later must be called with the lock held (so that allocation can - * free previously allocated buffers). Trying to free buffers that are mapped - * to user space will return -EBUSY. - * - * Video buffers are managed using two queues. However, unlike most USB video - * drivers that use an in queue and an out queue, we use a main queue to hold - * all queued buffers (both 'empty' and 'done' buffers), and an irq queue to - * hold empty buffers. This design (copied from video-buf) minimizes locking - * in interrupt, as only one queue is shared between interrupt and user - * contexts. - * - * Use cases - * --------- - * - * Unless stated otherwise, all operations that modify the irq buffers queue - * are protected by the irq spinlock. - * - * 1. The user queues the buffers, starts streaming and dequeues a buffer. - * - * The buffers are added to the main and irq queues. Both operations are - * protected by the queue lock, and the later is protected by the irq - * spinlock as well. - * - * The completion handler fetches a buffer from the irq queue and fills it - * with video data. If no buffer is available (irq queue empty), the handler - * returns immediately. - * - * When the buffer is full, the completion handler removes it from the irq - * queue, marks it as ready (UVC_BUF_STATE_DONE) and wakes its wait queue. - * At that point, any process waiting on the buffer will be woken up. If a - * process tries to dequeue a buffer after it has been marked ready, the - * dequeing will succeed immediately. - * - * 2. Buffers are queued, user is waiting on a buffer and the device gets - * disconnected. - * - * When the device is disconnected, the kernel calls the completion handler - * with an appropriate status code. The handler marks all buffers in the - * irq queue as being erroneous (UVC_BUF_STATE_ERROR) and wakes them up so - * that any process waiting on a buffer gets woken up. - * - * Waking up up the first buffer on the irq list is not enough, as the - * process waiting on the buffer might restart the dequeue operation - * immediately. - * + * 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 void -uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type) -{ - mutex_init(&queue->mutex); - spin_lock_init(&queue->irqlock); - INIT_LIST_HEAD(&queue->mainqueue); - INIT_LIST_HEAD(&queue->irqqueue); - queue->type = type; -} - -/* - * Free the video buffers. - * - * This function must be called with the queue lock held. +/* ----------------------------------------------------------------------------- + * videobuf2 queue operations */ -static int uvc_free_buffers(struct uvc_video_queue *queue) + +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[]) { - unsigned int i; + struct uvc_video_queue *queue = vb2_get_drv_priv(vq); + struct uvc_video *video = container_of(queue, struct uvc_video, queue); - for (i = 0; i < queue->count; ++i) { - if (queue->buffer[i].vma_use_count != 0) - return -EBUSY; - } + if (*nbuffers > UVC_MAX_VIDEO_BUFFERS) + *nbuffers = UVC_MAX_VIDEO_BUFFERS; - if (queue->count) { - vfree(queue->mem); - queue->count = 0; - } + *nplanes = 1; + + sizes[0] = video->imagesize; return 0; } -/* - * Allocate the video buffers. - * - * Pages are reserved to make sure they will not be swapped, as they will be - * filled in the URB completion handler. - * - * Buffers will be individually mapped, so they must all be page aligned. - */ -static int -uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers, - unsigned int buflength) +static int uvc_buffer_prepare(struct vb2_buffer *vb) { - unsigned int bufsize = PAGE_ALIGN(buflength); - unsigned int i; - void *mem = NULL; - int ret; + struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); + struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); - if (nbuffers > UVC_MAX_VIDEO_BUFFERS) - nbuffers = UVC_MAX_VIDEO_BUFFERS; + 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; + } - mutex_lock(&queue->mutex); + if (unlikely(queue->flags & UVC_QUEUE_DISCONNECTED)) + return -ENODEV; - if ((ret = uvc_free_buffers(queue)) < 0) - goto done; + 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); - /* Bail out if no buffers should be allocated. */ - if (nbuffers == 0) - goto done; + return 0; +} - /* Decrement the number of buffers until allocation succeeds. */ - for (; nbuffers > 0; --nbuffers) { - mem = vmalloc_32(nbuffers * bufsize); - if (mem != NULL) - break; - } +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; - if (mem == NULL) { - ret = -ENOMEM; - goto done; - } + spin_lock_irqsave(&queue->irqlock, flags); - for (i = 0; i < nbuffers; ++i) { - memset(&queue->buffer[i], 0, sizeof queue->buffer[i]); - queue->buffer[i].buf.index = i; - queue->buffer[i].buf.m.offset = i * bufsize; - queue->buffer[i].buf.length = buflength; - queue->buffer[i].buf.type = queue->type; - queue->buffer[i].buf.sequence = 0; - queue->buffer[i].buf.field = V4L2_FIELD_NONE; - queue->buffer[i].buf.memory = V4L2_MEMORY_MMAP; - queue->buffer[i].buf.flags = 0; - init_waitqueue_head(&queue->buffer[i].wait); + 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); } - queue->mem = mem; - queue->count = nbuffers; - queue->buf_size = bufsize; - ret = nbuffers; - -done: - mutex_unlock(&queue->mutex); - return ret; + spin_unlock_irqrestore(&queue->irqlock, flags); } -static void __uvc_query_buffer(struct uvc_buffer *buf, - struct v4l2_buffer *v4l2_buf) -{ - memcpy(v4l2_buf, &buf->buf, sizeof *v4l2_buf); - - if (buf->vma_use_count) - v4l2_buf->flags |= V4L2_BUF_FLAG_MAPPED; - - switch (buf->state) { - case UVC_BUF_STATE_ERROR: - case UVC_BUF_STATE_DONE: - v4l2_buf->flags |= V4L2_BUF_FLAG_DONE; - break; - case UVC_BUF_STATE_QUEUED: - case UVC_BUF_STATE_ACTIVE: - v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED; - break; - case UVC_BUF_STATE_IDLE: - default: - break; - } -} +static struct vb2_ops uvc_queue_qops = { + .queue_setup = uvc_queue_setup, + .buf_prepare = uvc_buffer_prepare, + .buf_queue = uvc_buffer_queue, +}; -static int -uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf) +static int uvc_queue_init(struct uvc_video_queue *queue, + enum v4l2_buf_type type) { - int ret = 0; + int ret; - mutex_lock(&queue->mutex); - if (v4l2_buf->index >= queue->count) { - ret = -EINVAL; - goto done; - } + 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; + 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 = 0; - __uvc_query_buffer(&queue->buffer[v4l2_buf->index], v4l2_buf); + return 0; +} -done: +/* + * Free the video buffers. + */ +static void uvc_free_buffers(struct uvc_video_queue *queue) +{ + mutex_lock(&queue->mutex); + vb2_queue_release(&queue->queue); mutex_unlock(&queue->mutex); - return ret; } /* - * Queue a video buffer. Attempting to queue a buffer that has already been - * queued will return -EINVAL. + * Allocate the video buffers. */ -static int -uvc_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf) +static int uvc_alloc_buffers(struct uvc_video_queue *queue, + struct v4l2_requestbuffers *rb) { - struct uvc_buffer *buf; - unsigned long flags; - int ret = 0; + int ret; - uvc_trace(UVC_TRACE_CAPTURE, "Queuing buffer %u.\n", v4l2_buf->index); + mutex_lock(&queue->mutex); + ret = vb2_reqbufs(&queue->queue, rb); + mutex_unlock(&queue->mutex); - if (v4l2_buf->type != queue->type || - v4l2_buf->memory != V4L2_MEMORY_MMAP) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer type (%u) " - "and/or memory (%u).\n", v4l2_buf->type, - v4l2_buf->memory); - return -EINVAL; - } + return ret ? ret : rb->count; +} - mutex_lock(&queue->mutex); - if (v4l2_buf->index >= queue->count) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Out of range index.\n"); - ret = -EINVAL; - goto done; - } +static int uvc_query_buffer(struct uvc_video_queue *queue, + struct v4l2_buffer *buf) +{ + int ret; - buf = &queue->buffer[v4l2_buf->index]; - if (buf->state != UVC_BUF_STATE_IDLE) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer state " - "(%u).\n", buf->state); - ret = -EINVAL; - goto done; - } + mutex_lock(&queue->mutex); + ret = vb2_querybuf(&queue->queue, buf); + mutex_unlock(&queue->mutex); - if (v4l2_buf->type == V4L2_BUF_TYPE_VIDEO_OUTPUT && - v4l2_buf->bytesused > buf->buf.length) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Bytes used out of bounds.\n"); - ret = -EINVAL; - goto done; - } + return ret; +} - if (v4l2_buf->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) - buf->buf.bytesused = 0; - else - buf->buf.bytesused = v4l2_buf->bytesused; +static int uvc_queue_buffer(struct uvc_video_queue *queue, + struct v4l2_buffer *buf) +{ + unsigned long flags; + int ret; + mutex_lock(&queue->mutex); + ret = vb2_qbuf(&queue->queue, buf); spin_lock_irqsave(&queue->irqlock, flags); - if (queue->flags & UVC_QUEUE_DISCONNECTED) { - spin_unlock_irqrestore(&queue->irqlock, flags); - ret = -ENODEV; - goto done; - } - buf->state = UVC_BUF_STATE_QUEUED; - ret = (queue->flags & UVC_QUEUE_PAUSED) != 0; queue->flags &= ~UVC_QUEUE_PAUSED; - - list_add_tail(&buf->stream, &queue->mainqueue); - list_add_tail(&buf->queue, &queue->irqqueue); spin_unlock_irqrestore(&queue->irqlock, flags); - -done: mutex_unlock(&queue->mutex); - return ret; -} -static int uvc_queue_waiton(struct uvc_buffer *buf, int nonblocking) -{ - if (nonblocking) { - return (buf->state != UVC_BUF_STATE_QUEUED && - buf->state != UVC_BUF_STATE_ACTIVE) - ? 0 : -EAGAIN; - } - - return wait_event_interruptible(buf->wait, - buf->state != UVC_BUF_STATE_QUEUED && - buf->state != UVC_BUF_STATE_ACTIVE); + return ret; } /* * Dequeue a video buffer. If nonblocking is false, block until a buffer is * available. */ -static int -uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf, - int nonblocking) +static int uvc_dequeue_buffer(struct uvc_video_queue *queue, + struct v4l2_buffer *buf, int nonblocking) { - struct uvc_buffer *buf; - int ret = 0; - - if (v4l2_buf->type != queue->type || - v4l2_buf->memory != V4L2_MEMORY_MMAP) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer type (%u) " - "and/or memory (%u).\n", v4l2_buf->type, - v4l2_buf->memory); - return -EINVAL; - } + int ret; mutex_lock(&queue->mutex); - if (list_empty(&queue->mainqueue)) { - uvc_trace(UVC_TRACE_CAPTURE, "[E] Empty buffer queue.\n"); - ret = -EINVAL; - goto done; - } - - buf = list_first_entry(&queue->mainqueue, struct uvc_buffer, stream); - if ((ret = uvc_queue_waiton(buf, nonblocking)) < 0) - goto done; - - uvc_trace(UVC_TRACE_CAPTURE, "Dequeuing buffer %u (%u, %u bytes).\n", - buf->buf.index, buf->state, buf->buf.bytesused); - - switch (buf->state) { - case UVC_BUF_STATE_ERROR: - uvc_trace(UVC_TRACE_CAPTURE, "[W] Corrupted data " - "(transmission error).\n"); - ret = -EIO; - case UVC_BUF_STATE_DONE: - buf->state = UVC_BUF_STATE_IDLE; - break; - - case UVC_BUF_STATE_IDLE: - case UVC_BUF_STATE_QUEUED: - case UVC_BUF_STATE_ACTIVE: - default: - uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer state %u " - "(driver bug?).\n", buf->state); - ret = -EINVAL; - goto done; - } - - list_del(&buf->stream); - __uvc_query_buffer(buf, v4l2_buf); - -done: + ret = vb2_dqbuf(&queue->queue, buf, nonblocking); mutex_unlock(&queue->mutex); + return ret; } @@ -361,105 +208,47 @@ done: * This function implements video queue polling and is intended to be used by * the device poll handler. */ -static unsigned int -uvc_queue_poll(struct uvc_video_queue *queue, struct file *file, - poll_table *wait) +static unsigned int uvc_queue_poll(struct uvc_video_queue *queue, + struct file *file, poll_table *wait) { - struct uvc_buffer *buf; - unsigned int mask = 0; + unsigned int ret; mutex_lock(&queue->mutex); - if (list_empty(&queue->mainqueue)) - goto done; - - buf = list_first_entry(&queue->mainqueue, struct uvc_buffer, stream); - - poll_wait(file, &buf->wait, wait); - if (buf->state == UVC_BUF_STATE_DONE || - buf->state == UVC_BUF_STATE_ERROR) - mask |= POLLOUT | POLLWRNORM; - -done: + ret = vb2_poll(&queue->queue, file, wait); mutex_unlock(&queue->mutex); - return mask; -} -/* - * VMA operations. - */ -static void uvc_vm_open(struct vm_area_struct *vma) -{ - struct uvc_buffer *buffer = vma->vm_private_data; - buffer->vma_use_count++; + return ret; } -static void uvc_vm_close(struct vm_area_struct *vma) +static int uvc_queue_mmap(struct uvc_video_queue *queue, + struct vm_area_struct *vma) { - struct uvc_buffer *buffer = vma->vm_private_data; - buffer->vma_use_count--; -} + int ret; -static struct vm_operations_struct uvc_vm_ops = { - .open = uvc_vm_open, - .close = uvc_vm_close, -}; + mutex_lock(&queue->mutex); + ret = vb2_mmap(&queue->queue, vma); + mutex_unlock(&queue->mutex); + + return ret; +} +#ifndef CONFIG_MMU /* - * Memory-map a buffer. + * Get unmapped area. * - * This function implements video buffer memory mapping and is intended to be - * used by the device mmap handler. + * NO-MMU arch need this function to make mmap() work correctly. */ -static int -uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma) +static unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue, + unsigned long pgoff) { - struct uvc_buffer *uninitialized_var(buffer); - struct page *page; - unsigned long addr, start, size; - unsigned int i; - int ret = 0; - - start = vma->vm_start; - size = vma->vm_end - vma->vm_start; + unsigned long ret; mutex_lock(&queue->mutex); - - for (i = 0; i < queue->count; ++i) { - buffer = &queue->buffer[i]; - if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff) - break; - } - - if (i == queue->count || size != queue->buf_size) { - ret = -EINVAL; - goto done; - } - - /* - * VM_IO marks the area as being an mmaped region for I/O to a - * device. It also prevents the region from being core dumped. - */ - vma->vm_flags |= VM_IO; - - addr = (unsigned long)queue->mem + buffer->buf.m.offset; - while (size > 0) { - page = vmalloc_to_page((void *)addr); - if ((ret = vm_insert_page(vma, start, page)) < 0) - goto done; - - start += PAGE_SIZE; - addr += PAGE_SIZE; - size -= PAGE_SIZE; - } - - vma->vm_ops = &uvc_vm_ops; - vma->vm_private_data = buffer; - uvc_vm_open(vma); - -done: + ret = vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0); mutex_unlock(&queue->mutex); return ret; } +#endif /* * Cancel the video buffers queue. @@ -484,7 +273,7 @@ static void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect) queue); list_del(&buf->queue); buf->state = UVC_BUF_STATE_ERROR; - wake_up(&buf->wait); + 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 @@ -516,26 +305,33 @@ static void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect) */ static int uvc_queue_enable(struct uvc_video_queue *queue, int enable) { - unsigned int i; + unsigned long flags; int ret = 0; mutex_lock(&queue->mutex); if (enable) { - if (uvc_queue_streaming(queue)) { - ret = -EBUSY; + ret = vb2_streamon(&queue->queue, queue->queue.type); + if (ret < 0) goto done; - } + queue->sequence = 0; - queue->flags |= UVC_QUEUE_STREAMING; queue->buf_used = 0; } else { - uvc_queue_cancel(queue, 0); - INIT_LIST_HEAD(&queue->mainqueue); + ret = vb2_streamoff(&queue->queue, queue->queue.type); + if (ret < 0) + goto done; - for (i = 0; i < queue->count; ++i) - queue->buffer[i].state = UVC_BUF_STATE_IDLE; + spin_lock_irqsave(&queue->irqlock, flags); + INIT_LIST_HEAD(&queue->irqqueue); - queue->flags &= ~UVC_QUEUE_STREAMING; + /* + * 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); } done: @@ -544,15 +340,15 @@ done: } /* called with &queue_irqlock held.. */ -static struct uvc_buffer * -uvc_queue_next_buffer(struct uvc_video_queue *queue, struct uvc_buffer *buf) +static struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue, + struct uvc_buffer *buf) { struct uvc_buffer *nextbuf; if ((queue->flags & UVC_QUEUE_DROP_INCOMPLETE) && - buf->buf.length != buf->buf.bytesused) { + buf->length != buf->bytesused) { buf->state = UVC_BUF_STATE_QUEUED; - buf->buf.bytesused = 0; + vb2_set_plane_payload(&buf->buf, 0, 0); return buf; } @@ -563,10 +359,18 @@ uvc_queue_next_buffer(struct uvc_video_queue *queue, struct uvc_buffer *buf) else nextbuf = NULL; - buf->buf.sequence = queue->sequence++; - do_gettimeofday(&buf->buf.timestamp); + /* + * FIXME: with videobuf2, the sequence number or timestamp fields + * are valid only for video capture devices and the UVC gadget usually + * is a video output device. Keeping these until the specs are clear on + * this aspect. + */ + buf->buf.v4l2_buf.sequence = queue->sequence++; + do_gettimeofday(&buf->buf.v4l2_buf.timestamp); + + vb2_set_plane_payload(&buf->buf, 0, buf->bytesused); + vb2_buffer_done(&buf->buf, VB2_BUF_STATE_DONE); - wake_up(&buf->wait); return nextbuf; } |