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-rw-r--r--include/media/videobuf-core.h233
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diff --git a/include/media/videobuf-core.h b/include/media/videobuf-core.h
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * generic helper functions for handling video4linux capture buffers
+ *
+ * (c) 2007 Mauro Carvalho Chehab, <mchehab@kernel.org>
+ *
+ * Highly based on video-buf written originally by:
+ * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
+ * (c) 2006 Mauro Carvalho Chehab, <mchehab@kernel.org>
+ * (c) 2006 Ted Walther and John Sokol
+ */
+
+#ifndef _VIDEOBUF_CORE_H
+#define _VIDEOBUF_CORE_H
+
+#include <linux/poll.h>
+#include <linux/videodev2.h>
+
+#define UNSET (-1U)
+
+
+struct videobuf_buffer;
+struct videobuf_queue;
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * A small set of helper functions to manage video4linux buffers.
+ *
+ * struct videobuf_buffer holds the data structures used by the helper
+ * functions, additionally some commonly used fields for v4l buffers
+ * (width, height, lists, waitqueue) are in there. That struct should
+ * be used as first element in the drivers buffer struct.
+ *
+ * about the mmap helpers (videobuf_mmap_*):
+ *
+ * The mmaper function allows to map any subset of contiguous buffers.
+ * This includes one mmap() call for all buffers (which the original
+ * video4linux API uses) as well as one mmap() for every single buffer
+ * (which v4l2 uses).
+ *
+ * If there is a valid mapping for a buffer, buffer->baddr/bsize holds
+ * userspace address + size which can be fed into the
+ * videobuf_dma_init_user function listed above.
+ *
+ */
+
+struct videobuf_mapping {
+ unsigned int count;
+ struct videobuf_queue *q;
+};
+
+enum videobuf_state {
+ VIDEOBUF_NEEDS_INIT = 0,
+ VIDEOBUF_PREPARED = 1,
+ VIDEOBUF_QUEUED = 2,
+ VIDEOBUF_ACTIVE = 3,
+ VIDEOBUF_DONE = 4,
+ VIDEOBUF_ERROR = 5,
+ VIDEOBUF_IDLE = 6,
+};
+
+struct videobuf_buffer {
+ unsigned int i;
+ u32 magic;
+
+ /* info about the buffer */
+ unsigned int width;
+ unsigned int height;
+ unsigned int bytesperline; /* use only if != 0 */
+ unsigned long size;
+ enum v4l2_field field;
+ enum videobuf_state state;
+ struct list_head stream; /* QBUF/DQBUF list */
+
+ /* touched by irq handler */
+ struct list_head queue;
+ wait_queue_head_t done;
+ unsigned int field_count;
+ u64 ts;
+
+ /* Memory type */
+ enum v4l2_memory memory;
+
+ /* buffer size */
+ size_t bsize;
+
+ /* buffer offset (mmap + overlay) */
+ size_t boff;
+
+ /* buffer addr (userland ptr!) */
+ unsigned long baddr;
+
+ /* for mmap'ed buffers */
+ struct videobuf_mapping *map;
+
+ /* Private pointer to allow specific methods to store their data */
+ int privsize;
+ void *priv;
+};
+
+struct videobuf_queue_ops {
+ int (*buf_setup)(struct videobuf_queue *q,
+ unsigned int *count, unsigned int *size);
+ int (*buf_prepare)(struct videobuf_queue *q,
+ struct videobuf_buffer *vb,
+ enum v4l2_field field);
+ void (*buf_queue)(struct videobuf_queue *q,
+ struct videobuf_buffer *vb);
+ void (*buf_release)(struct videobuf_queue *q,
+ struct videobuf_buffer *vb);
+};
+
+#define MAGIC_QTYPE_OPS 0x12261003
+
+/* Helper operations - device type dependent */
+struct videobuf_qtype_ops {
+ u32 magic;
+
+ struct videobuf_buffer *(*alloc_vb)(size_t size);
+ void *(*vaddr) (struct videobuf_buffer *buf);
+ int (*iolock) (struct videobuf_queue *q,
+ struct videobuf_buffer *vb,
+ struct v4l2_framebuffer *fbuf);
+ int (*sync) (struct videobuf_queue *q,
+ struct videobuf_buffer *buf);
+ int (*mmap_mapper) (struct videobuf_queue *q,
+ struct videobuf_buffer *buf,
+ struct vm_area_struct *vma);
+};
+
+struct videobuf_queue {
+ struct mutex vb_lock;
+ struct mutex *ext_lock;
+ spinlock_t *irqlock;
+ struct device *dev;
+
+ wait_queue_head_t wait; /* wait if queue is empty */
+
+ enum v4l2_buf_type type;
+ unsigned int msize;
+ enum v4l2_field field;
+ enum v4l2_field last; /* for field=V4L2_FIELD_ALTERNATE */
+ struct videobuf_buffer *bufs[VIDEO_MAX_FRAME];
+ const struct videobuf_queue_ops *ops;
+ struct videobuf_qtype_ops *int_ops;
+
+ unsigned int streaming:1;
+ unsigned int reading:1;
+
+ /* capture via mmap() + ioctl(QBUF/DQBUF) */
+ struct list_head stream;
+
+ /* capture via read() */
+ unsigned int read_off;
+ struct videobuf_buffer *read_buf;
+
+ /* driver private data */
+ void *priv_data;
+};
+
+static inline void videobuf_queue_lock(struct videobuf_queue *q)
+{
+ if (!q->ext_lock)
+ mutex_lock(&q->vb_lock);
+}
+
+static inline void videobuf_queue_unlock(struct videobuf_queue *q)
+{
+ if (!q->ext_lock)
+ mutex_unlock(&q->vb_lock);
+}
+
+int videobuf_waiton(struct videobuf_queue *q, struct videobuf_buffer *vb,
+ int non_blocking, int intr);
+int videobuf_iolock(struct videobuf_queue *q, struct videobuf_buffer *vb,
+ struct v4l2_framebuffer *fbuf);
+
+struct videobuf_buffer *videobuf_alloc_vb(struct videobuf_queue *q);
+
+/* Used on videobuf-dvb */
+void *videobuf_queue_to_vaddr(struct videobuf_queue *q,
+ struct videobuf_buffer *buf);
+
+void videobuf_queue_core_init(struct videobuf_queue *q,
+ const struct videobuf_queue_ops *ops,
+ struct device *dev,
+ spinlock_t *irqlock,
+ enum v4l2_buf_type type,
+ enum v4l2_field field,
+ unsigned int msize,
+ void *priv,
+ struct videobuf_qtype_ops *int_ops,
+ struct mutex *ext_lock);
+int videobuf_queue_is_busy(struct videobuf_queue *q);
+void videobuf_queue_cancel(struct videobuf_queue *q);
+
+enum v4l2_field videobuf_next_field(struct videobuf_queue *q);
+int videobuf_reqbufs(struct videobuf_queue *q,
+ struct v4l2_requestbuffers *req);
+int videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b);
+int videobuf_qbuf(struct videobuf_queue *q,
+ struct v4l2_buffer *b);
+int videobuf_dqbuf(struct videobuf_queue *q,
+ struct v4l2_buffer *b, int nonblocking);
+int videobuf_streamon(struct videobuf_queue *q);
+int videobuf_streamoff(struct videobuf_queue *q);
+
+void videobuf_stop(struct videobuf_queue *q);
+
+int videobuf_read_start(struct videobuf_queue *q);
+void videobuf_read_stop(struct videobuf_queue *q);
+ssize_t videobuf_read_stream(struct videobuf_queue *q,
+ char __user *data, size_t count, loff_t *ppos,
+ int vbihack, int nonblocking);
+ssize_t videobuf_read_one(struct videobuf_queue *q,
+ char __user *data, size_t count, loff_t *ppos,
+ int nonblocking);
+__poll_t videobuf_poll_stream(struct file *file,
+ struct videobuf_queue *q,
+ poll_table *wait);
+
+int videobuf_mmap_setup(struct videobuf_queue *q,
+ unsigned int bcount, unsigned int bsize,
+ enum v4l2_memory memory);
+int __videobuf_mmap_setup(struct videobuf_queue *q,
+ unsigned int bcount, unsigned int bsize,
+ enum v4l2_memory memory);
+int videobuf_mmap_free(struct videobuf_queue *q);
+int videobuf_mmap_mapper(struct videobuf_queue *q,
+ struct vm_area_struct *vma);
+
+#endif