xref: /linux/drivers/usb/gadget/function/uvc_queue.h (revision 2eff01ee2881becc9daaa0d53477ec202136b1f4)
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 	/* req_payload_size: only used with isoc */
43 	unsigned int req_payload_size;
44 };
45 
46 #define UVC_QUEUE_DISCONNECTED		(1 << 0)
47 #define UVC_QUEUE_DROP_INCOMPLETE	(1 << 1)
48 
49 struct uvc_video_queue {
50 	struct vb2_queue queue;
51 
52 	unsigned int flags;
53 	__u32 sequence;
54 
55 	unsigned int buf_used;
56 
57 	bool use_sg;
58 
59 	spinlock_t irqlock;	/* Protects flags and irqqueue */
60 	struct list_head irqqueue;
61 };
62 
63 static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
64 {
65 	return vb2_is_streaming(&queue->queue);
66 }
67 
68 int uvcg_queue_init(struct uvc_video_queue *queue, struct device *dev, enum v4l2_buf_type type,
69 		    struct mutex *lock);
70 
71 void uvcg_free_buffers(struct uvc_video_queue *queue);
72 
73 int uvcg_alloc_buffers(struct uvc_video_queue *queue,
74 		       struct v4l2_requestbuffers *rb);
75 
76 int uvcg_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf);
77 
78 int uvcg_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf);
79 
80 int uvcg_dequeue_buffer(struct uvc_video_queue *queue,
81 			struct v4l2_buffer *buf, int nonblocking);
82 
83 __poll_t uvcg_queue_poll(struct uvc_video_queue *queue,
84 			     struct file *file, poll_table *wait);
85 
86 int uvcg_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma);
87 
88 #ifndef CONFIG_MMU
89 unsigned long uvcg_queue_get_unmapped_area(struct uvc_video_queue *queue,
90 					   unsigned long pgoff);
91 #endif /* CONFIG_MMU */
92 
93 void uvcg_queue_cancel(struct uvc_video_queue *queue, int disconnect);
94 
95 int uvcg_queue_enable(struct uvc_video_queue *queue, int enable);
96 
97 void uvcg_complete_buffer(struct uvc_video_queue *queue,
98 					  struct uvc_buffer *buf);
99 
100 struct uvc_buffer *uvcg_queue_head(struct uvc_video_queue *queue);
101 
102 #endif /* _UVC_QUEUE_H_ */
103 
104