xref: /linux/drivers/usb/gadget/function/uvc_queue.h (revision 791d3ef2e11100449837dc0b6fe884e60ca3a484)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _UVC_QUEUE_H_
3 #define _UVC_QUEUE_H_
4 
5 #ifdef __KERNEL__
6 
7 #include <linux/kernel.h>
8 #include <linux/poll.h>
9 #include <linux/videodev2.h>
10 #include <media/videobuf2-v4l2.h>
11 
12 /* Maximum frame size in bytes, for sanity checking. */
13 #define UVC_MAX_FRAME_SIZE	(16*1024*1024)
14 /* Maximum number of video buffers. */
15 #define UVC_MAX_VIDEO_BUFFERS	32
16 
17 /* ------------------------------------------------------------------------
18  * Structures.
19  */
20 
21 enum uvc_buffer_state {
22 	UVC_BUF_STATE_IDLE	= 0,
23 	UVC_BUF_STATE_QUEUED	= 1,
24 	UVC_BUF_STATE_ACTIVE	= 2,
25 	UVC_BUF_STATE_DONE	= 3,
26 	UVC_BUF_STATE_ERROR	= 4,
27 };
28 
29 struct uvc_buffer {
30 	struct vb2_v4l2_buffer buf;
31 	struct list_head queue;
32 
33 	enum uvc_buffer_state state;
34 	void *mem;
35 	unsigned int length;
36 	unsigned int bytesused;
37 };
38 
39 #define UVC_QUEUE_DISCONNECTED		(1 << 0)
40 #define UVC_QUEUE_DROP_INCOMPLETE	(1 << 1)
41 #define UVC_QUEUE_PAUSED		(1 << 2)
42 
43 struct uvc_video_queue {
44 	struct vb2_queue queue;
45 
46 	unsigned int flags;
47 	__u32 sequence;
48 
49 	unsigned int buf_used;
50 
51 	spinlock_t irqlock;	/* Protects flags and irqqueue */
52 	struct list_head irqqueue;
53 };
54 
55 static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
56 {
57 	return vb2_is_streaming(&queue->queue);
58 }
59 
60 int uvcg_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
61 		    struct mutex *lock);
62 
63 void uvcg_free_buffers(struct uvc_video_queue *queue);
64 
65 int uvcg_alloc_buffers(struct uvc_video_queue *queue,
66 		       struct v4l2_requestbuffers *rb);
67 
68 int uvcg_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf);
69 
70 int uvcg_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf);
71 
72 int uvcg_dequeue_buffer(struct uvc_video_queue *queue,
73 			struct v4l2_buffer *buf, int nonblocking);
74 
75 __poll_t uvcg_queue_poll(struct uvc_video_queue *queue,
76 			     struct file *file, poll_table *wait);
77 
78 int uvcg_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma);
79 
80 #ifndef CONFIG_MMU
81 unsigned long uvcg_queue_get_unmapped_area(struct uvc_video_queue *queue,
82 					   unsigned long pgoff);
83 #endif /* CONFIG_MMU */
84 
85 void uvcg_queue_cancel(struct uvc_video_queue *queue, int disconnect);
86 
87 int uvcg_queue_enable(struct uvc_video_queue *queue, int enable);
88 
89 struct uvc_buffer *uvcg_queue_next_buffer(struct uvc_video_queue *queue,
90 					  struct uvc_buffer *buf);
91 
92 struct uvc_buffer *uvcg_queue_head(struct uvc_video_queue *queue);
93 
94 #endif /* __KERNEL__ */
95 
96 #endif /* _UVC_QUEUE_H_ */
97 
98