/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _UVC_QUEUE_H_
#define _UVC_QUEUE_H_

#include <linux/list.h>
#include <linux/poll.h>
#include <linux/spinlock.h>

#include <media/videobuf2-v4l2.h>

struct file;
struct mutex;

/* Maximum frame size in bytes, for sanity checking. */
#define UVC_MAX_FRAME_SIZE      (16*1024*1024)
/* Maximum number of video buffers. */
#define UVC_MAX_VIDEO_BUFFERS   32

/* ------------------------------------------------------------------------
 * Structures.
 */

enum uvc_buffer_state {
        UVC_BUF_STATE_IDLE      = 0,
        UVC_BUF_STATE_QUEUED    = 1,
        UVC_BUF_STATE_ACTIVE    = 2,
        UVC_BUF_STATE_DONE      = 3,
        UVC_BUF_STATE_ERROR     = 4,
};

struct uvc_buffer {
        struct vb2_v4l2_buffer buf;
        struct list_head queue;

        enum uvc_buffer_state state;
        void *mem;
        struct sg_table *sgt;
        struct scatterlist *sg;
        unsigned int offset;
        unsigned int length;
        unsigned int bytesused;
        /* req_payload_size: only used with isoc */
        unsigned int req_payload_size;
};

#define UVC_QUEUE_DISCONNECTED          (1 << 0)
#define UVC_QUEUE_DROP_INCOMPLETE       (1 << 1)

struct uvc_video_queue {
        struct vb2_queue queue;

        unsigned int flags;
        __u32 sequence;

        unsigned int buf_used;

        bool use_sg;

        spinlock_t irqlock;     /* Protects flags and irqqueue */
        struct list_head irqqueue;
};

static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
{
        return vb2_is_streaming(&queue->queue);
}

int uvcg_queue_init(struct uvc_video_queue *queue, struct device *dev, enum v4l2_buf_type type,
                    struct mutex *lock);

void uvcg_free_buffers(struct uvc_video_queue *queue);

int uvcg_alloc_buffers(struct uvc_video_queue *queue,
                       struct v4l2_requestbuffers *rb);

int uvcg_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf);

int uvcg_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf);

int uvcg_dequeue_buffer(struct uvc_video_queue *queue,
                        struct v4l2_buffer *buf, int nonblocking);

__poll_t uvcg_queue_poll(struct uvc_video_queue *queue,
                             struct file *file, poll_table *wait);

int uvcg_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma);

#ifndef CONFIG_MMU
unsigned long uvcg_queue_get_unmapped_area(struct uvc_video_queue *queue,
                                           unsigned long pgoff);
#endif /* CONFIG_MMU */

void uvcg_queue_cancel(struct uvc_video_queue *queue, int disconnect);

int uvcg_queue_enable(struct uvc_video_queue *queue, int enable);

void uvcg_complete_buffer(struct uvc_video_queue *queue,
                                          struct uvc_buffer *buf);

struct uvc_buffer *uvcg_queue_head(struct uvc_video_queue *queue);

#endif /* _UVC_QUEUE_H_ */