xref: /linux/drivers/usb/gadget/function/uvc_queue.h (revision a4eb44a6435d6d8f9e642407a4a06f65eb90ca04)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _UVC_QUEUE_H_
3 #define _UVC_QUEUE_H_
4 
5 #include <linux/list.h>
6 #include <linux/poll.h>
7 #include <linux/spinlock.h>
8 
9 #include <media/videobuf2-v4l2.h>
10 
11 struct file;
12 struct mutex;
13 
14 /* Maximum frame size in bytes, for sanity checking. */
15 #define UVC_MAX_FRAME_SIZE	(16*1024*1024)
16 /* Maximum number of video buffers. */
17 #define UVC_MAX_VIDEO_BUFFERS	32
18 
19 /* ------------------------------------------------------------------------
20  * Structures.
21  */
22 
23 enum uvc_buffer_state {
24 	UVC_BUF_STATE_IDLE	= 0,
25 	UVC_BUF_STATE_QUEUED	= 1,
26 	UVC_BUF_STATE_ACTIVE	= 2,
27 	UVC_BUF_STATE_DONE	= 3,
28 	UVC_BUF_STATE_ERROR	= 4,
29 };
30 
31 struct uvc_buffer {
32 	struct vb2_v4l2_buffer buf;
33 	struct list_head queue;
34 
35 	enum uvc_buffer_state state;
36 	void *mem;
37 	struct sg_table *sgt;
38 	struct scatterlist *sg;
39 	unsigned int offset;
40 	unsigned int length;
41 	unsigned int bytesused;
42 };
43 
44 #define UVC_QUEUE_DISCONNECTED		(1 << 0)
45 #define UVC_QUEUE_DROP_INCOMPLETE	(1 << 1)
46 #define UVC_QUEUE_PAUSED		(1 << 2)
47 
48 struct uvc_video_queue {
49 	struct vb2_queue queue;
50 
51 	unsigned int flags;
52 	__u32 sequence;
53 
54 	unsigned int buf_used;
55 
56 	bool use_sg;
57 
58 	spinlock_t irqlock;	/* Protects flags and irqqueue */
59 	struct list_head irqqueue;
60 };
61 
62 static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
63 {
64 	return vb2_is_streaming(&queue->queue);
65 }
66 
67 int uvcg_queue_init(struct uvc_video_queue *queue, struct device *dev, enum v4l2_buf_type type,
68 		    struct mutex *lock);
69 
70 void uvcg_free_buffers(struct uvc_video_queue *queue);
71 
72 int uvcg_alloc_buffers(struct uvc_video_queue *queue,
73 		       struct v4l2_requestbuffers *rb);
74 
75 int uvcg_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf);
76 
77 int uvcg_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf);
78 
79 int uvcg_dequeue_buffer(struct uvc_video_queue *queue,
80 			struct v4l2_buffer *buf, int nonblocking);
81 
82 __poll_t uvcg_queue_poll(struct uvc_video_queue *queue,
83 			     struct file *file, poll_table *wait);
84 
85 int uvcg_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma);
86 
87 #ifndef CONFIG_MMU
88 unsigned long uvcg_queue_get_unmapped_area(struct uvc_video_queue *queue,
89 					   unsigned long pgoff);
90 #endif /* CONFIG_MMU */
91 
92 void uvcg_queue_cancel(struct uvc_video_queue *queue, int disconnect);
93 
94 int uvcg_queue_enable(struct uvc_video_queue *queue, int enable);
95 
96 struct uvc_buffer *uvcg_queue_next_buffer(struct uvc_video_queue *queue,
97 					  struct uvc_buffer *buf);
98 
99 struct uvc_buffer *uvcg_queue_head(struct uvc_video_queue *queue);
100 
101 #endif /* _UVC_QUEUE_H_ */
102 
103