drivers/usb/gadget/uvc_queue.h

   1 #ifndef _UVC_QUEUE_H_
   2 #define _UVC_QUEUE_H_
   3
   4 #ifdef __KERNEL__
   5
   6 #include <linux/kernel.h>
   7 #include <linux/poll.h>
   8 #include <linux/videodev2.h>
   9
  10 /* Maximum frame size in bytes, for sanity checking. */
  11 #define UVC_MAX_FRAME_SIZE      (16*1024*1024)
  12 /* Maximum number of video buffers. */
  13 #define UVC_MAX_VIDEO_BUFFERS   32
  14
  15 /* ------------------------------------------------------------------------
  16  * Structures.
  17  */
  18
  19 enum uvc_buffer_state {
  20         UVC_BUF_STATE_IDLE      = 0,
  21         UVC_BUF_STATE_QUEUED    = 1,
  22         UVC_BUF_STATE_ACTIVE    = 2,
  23         UVC_BUF_STATE_DONE      = 3,
  24         UVC_BUF_STATE_ERROR     = 4,
  25 };
  26
  27 struct uvc_buffer {
  28         unsigned long vma_use_count;
  29         struct list_head stream;
  30
  31         /* Touched by interrupt handler. */
  32         struct v4l2_buffer buf;
  33         struct list_head queue;
  34         wait_queue_head_t wait;
  35         enum uvc_buffer_state state;
  36 };
  37
  38 #define UVC_QUEUE_STREAMING             (1 << 0)
  39 #define UVC_QUEUE_DISCONNECTED          (1 << 1)
  40 #define UVC_QUEUE_DROP_INCOMPLETE       (1 << 2)
  41 #define UVC_QUEUE_PAUSED                (1 << 3)
  42
  43 struct uvc_video_queue {
  44         enum v4l2_buf_type type;
  45
  46         void *mem;
  47         unsigned int flags;
  48         __u32 sequence;
  49
  50         unsigned int count;
  51         unsigned int buf_size;
  52         unsigned int buf_used;
  53         struct uvc_buffer buffer[UVC_MAX_VIDEO_BUFFERS];
  54         struct mutex mutex;     /* protects buffers and mainqueue */
  55         spinlock_t irqlock;     /* protects irqqueue */
  56
  57         struct list_head mainqueue;
  58         struct list_head irqqueue;
  59 };
  60
  61 extern void uvc_queue_init(struct uvc_video_queue *queue,
  62                 enum v4l2_buf_type type);
  63 extern int uvc_alloc_buffers(struct uvc_video_queue *queue,
  64                 unsigned int nbuffers, unsigned int buflength);
  65 extern int uvc_free_buffers(struct uvc_video_queue *queue);
  66 extern int uvc_query_buffer(struct uvc_video_queue *queue,
  67                 struct v4l2_buffer *v4l2_buf);
  68 extern int uvc_queue_buffer(struct uvc_video_queue *queue,
  69                 struct v4l2_buffer *v4l2_buf);
  70 extern int uvc_dequeue_buffer(struct uvc_video_queue *queue,
  71                 struct v4l2_buffer *v4l2_buf, int nonblocking);
  72 extern int uvc_queue_enable(struct uvc_video_queue *queue, int enable);
  73 extern void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect);
  74 extern struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
  75                 struct uvc_buffer *buf);
  76 extern unsigned int uvc_queue_poll(struct uvc_video_queue *queue,
  77                 struct file *file, poll_table *wait);
  78 extern int uvc_queue_mmap(struct uvc_video_queue *queue,
  79                 struct vm_area_struct *vma);
  80 static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
  81 {
  82         return queue->flags & UVC_QUEUE_STREAMING;
  83 }
  84 extern struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue);
  85
  86 #endif /* __KERNEL__ */
  87
  88 #endif /* _UVC_QUEUE_H_ */
  89