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Diffstat (limited to 'include/media/videobuf2-core.h')
-rw-r--r--include/media/videobuf2-core.h185
1 files changed, 152 insertions, 33 deletions
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index 6781258d0b6..8fab6fa0dbf 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -20,6 +20,7 @@
struct vb2_alloc_ctx;
struct vb2_fileio_data;
+struct vb2_threadio_data;
/**
* struct vb2_mem_ops - memory handling/memory allocator operations
@@ -34,56 +35,56 @@ struct vb2_fileio_data;
* usually will result in the allocator freeing the buffer (if
* no other users of this buffer are present); the buf_priv
* argument is the allocator private per-buffer structure
- * previously returned from the alloc callback
+ * previously returned from the alloc callback.
* @get_userptr: acquire userspace memory for a hardware operation; used for
* USERPTR memory types; vaddr is the address passed to the
* videobuf layer when queuing a video buffer of USERPTR type;
* should return an allocator private per-buffer structure
* associated with the buffer on success, NULL on failure;
* the returned private structure will then be passed as buf_priv
- * argument to other ops in this structure
+ * argument to other ops in this structure.
* @put_userptr: inform the allocator that a USERPTR buffer will no longer
- * be used
+ * be used.
* @attach_dmabuf: attach a shared struct dma_buf for a hardware operation;
* used for DMABUF memory types; alloc_ctx is the alloc context
* dbuf is the shared dma_buf; returns NULL on failure;
* allocator private per-buffer structure on success;
- * this needs to be used for further accesses to the buffer
+ * this needs to be used for further accesses to the buffer.
* @detach_dmabuf: inform the exporter of the buffer that the current DMABUF
* buffer is no longer used; the buf_priv argument is the
* allocator private per-buffer structure previously returned
- * from the attach_dmabuf callback
+ * from the attach_dmabuf callback.
* @map_dmabuf: request for access to the dmabuf from allocator; the allocator
* of dmabuf is informed that this driver is going to use the
- * dmabuf
+ * dmabuf.
* @unmap_dmabuf: releases access control to the dmabuf - allocator is notified
- * that this driver is done using the dmabuf for now
+ * that this driver is done using the dmabuf for now.
* @prepare: called every time the buffer is passed from userspace to the
- * driver, useful for cache synchronisation, optional
+ * driver, useful for cache synchronisation, optional.
* @finish: called every time the buffer is passed back from the driver
- * to the userspace, also optional
+ * to the userspace, also optional.
* @vaddr: return a kernel virtual address to a given memory buffer
* associated with the passed private structure or NULL if no
- * such mapping exists
+ * such mapping exists.
* @cookie: return allocator specific cookie for a given memory buffer
* associated with the passed private structure or NULL if not
- * available
+ * available.
* @num_users: return the current number of users of a memory buffer;
* return 1 if the videobuf layer (or actually the driver using
- * it) is the only user
+ * it) is the only user.
* @mmap: setup a userspace mapping for a given memory buffer under
- * the provided virtual memory region
+ * the provided virtual memory region.
*
* Required ops for USERPTR types: get_userptr, put_userptr.
* Required ops for MMAP types: alloc, put, num_users, mmap.
- * Required ops for read/write access types: alloc, put, num_users, vaddr
+ * Required ops for read/write access types: alloc, put, num_users, vaddr.
* Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, map_dmabuf,
* unmap_dmabuf.
*/
struct vb2_mem_ops {
void *(*alloc)(void *alloc_ctx, unsigned long size, gfp_t gfp_flags);
void (*put)(void *buf_priv);
- struct dma_buf *(*get_dmabuf)(void *buf_priv);
+ struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags);
void *(*get_userptr)(void *alloc_ctx, unsigned long vaddr,
unsigned long size, int write);
@@ -142,6 +143,7 @@ enum vb2_fileio_flags {
/**
* enum vb2_buffer_state - current video buffer state
* @VB2_BUF_STATE_DEQUEUED: buffer under userspace control
+ * @VB2_BUF_STATE_PREPARING: buffer is being prepared in videobuf
* @VB2_BUF_STATE_PREPARED: buffer prepared in videobuf and by the driver
* @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in driver
* @VB2_BUF_STATE_ACTIVE: buffer queued in driver and possibly used
@@ -154,6 +156,7 @@ enum vb2_fileio_flags {
*/
enum vb2_buffer_state {
VB2_BUF_STATE_DEQUEUED,
+ VB2_BUF_STATE_PREPARING,
VB2_BUF_STATE_PREPARED,
VB2_BUF_STATE_QUEUED,
VB2_BUF_STATE_ACTIVE,
@@ -201,6 +204,37 @@ struct vb2_buffer {
struct list_head done_entry;
struct vb2_plane planes[VIDEO_MAX_PLANES];
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+ /*
+ * Counters for how often these buffer-related ops are
+ * called. Used to check for unbalanced ops.
+ */
+ u32 cnt_mem_alloc;
+ u32 cnt_mem_put;
+ u32 cnt_mem_get_dmabuf;
+ u32 cnt_mem_get_userptr;
+ u32 cnt_mem_put_userptr;
+ u32 cnt_mem_prepare;
+ u32 cnt_mem_finish;
+ u32 cnt_mem_attach_dmabuf;
+ u32 cnt_mem_detach_dmabuf;
+ u32 cnt_mem_map_dmabuf;
+ u32 cnt_mem_unmap_dmabuf;
+ u32 cnt_mem_vaddr;
+ u32 cnt_mem_cookie;
+ u32 cnt_mem_num_users;
+ u32 cnt_mem_mmap;
+
+ u32 cnt_buf_init;
+ u32 cnt_buf_prepare;
+ u32 cnt_buf_finish;
+ u32 cnt_buf_cleanup;
+ u32 cnt_buf_queue;
+
+ /* This counts the number of calls to vb2_buffer_done() */
+ u32 cnt_buf_done;
+#endif
};
/**
@@ -225,35 +259,46 @@ struct vb2_buffer {
* @wait_prepare: release any locks taken while calling vb2 functions;
* it is called before an ioctl needs to wait for a new
* buffer to arrive; required to avoid a deadlock in
- * blocking access type
+ * blocking access type.
* @wait_finish: reacquire all locks released in the previous callback;
* required to continue operation after sleeping while
- * waiting for a new buffer to arrive
+ * waiting for a new buffer to arrive.
* @buf_init: called once after allocating a buffer (in MMAP case)
* or after acquiring a new USERPTR buffer; drivers may
* perform additional buffer-related initialization;
* initialization failure (return != 0) will prevent
- * queue setup from completing successfully; optional
+ * queue setup from completing successfully; optional.
* @buf_prepare: called every time the buffer is queued from userspace
* and from the VIDIOC_PREPARE_BUF ioctl; drivers may
* perform any initialization required before each hardware
* operation in this callback; drivers that support
* VIDIOC_CREATE_BUFS must also validate the buffer size;
* if an error is returned, the buffer will not be queued
- * in driver; optional
+ * in driver; optional.
* @buf_finish: called before every dequeue of the buffer back to
* userspace; drivers may perform any operations required
- * before userspace accesses the buffer; optional
+ * before userspace accesses the buffer; optional. The
+ * buffer state can be one of the following: DONE and
+ * ERROR occur while streaming is in progress, and the
+ * PREPARED state occurs when the queue has been canceled
+ * and all pending buffers are being returned to their
+ * default DEQUEUED state. Typically you only have to do
+ * something if the state is VB2_BUF_STATE_DONE, since in
+ * all other cases the buffer contents will be ignored
+ * anyway.
* @buf_cleanup: called once before the buffer is freed; drivers may
- * perform any additional cleanup; optional
+ * perform any additional cleanup; optional.
* @start_streaming: called once to enter 'streaming' state; the driver may
* receive buffers with @buf_queue callback before
* @start_streaming is called; the driver gets the number
* of already queued buffers in count parameter; driver
- * can return an error if hardware fails or not enough
- * buffers has been queued, in such case all buffers that
- * have been already given by the @buf_queue callback are
- * invalidated.
+ * can return an error if hardware fails, in that case all
+ * buffers that have been already given by the @buf_queue
+ * callback are invalidated.
+ * If there were not enough queued buffers to start
+ * streaming, then this callback returns -ENOBUFS, and the
+ * vb2 core will retry calling @start_streaming when a new
+ * buffer is queued.
* @stop_streaming: called when 'streaming' state must be disabled; driver
* should stop any DMA transactions or wait until they
* finish and give back all buffers it got from buf_queue()
@@ -263,7 +308,7 @@ struct vb2_buffer {
* the buffer back by calling vb2_buffer_done() function;
* it is allways called after calling STREAMON ioctl;
* might be called before start_streaming callback if user
- * pre-queued buffers before calling STREAMON
+ * pre-queued buffers before calling STREAMON.
*/
struct vb2_ops {
int (*queue_setup)(struct vb2_queue *q, const struct v4l2_format *fmt,
@@ -275,11 +320,11 @@ struct vb2_ops {
int (*buf_init)(struct vb2_buffer *vb);
int (*buf_prepare)(struct vb2_buffer *vb);
- int (*buf_finish)(struct vb2_buffer *vb);
+ void (*buf_finish)(struct vb2_buffer *vb);
void (*buf_cleanup)(struct vb2_buffer *vb);
int (*start_streaming)(struct vb2_queue *q, unsigned int count);
- int (*stop_streaming)(struct vb2_queue *q);
+ void (*stop_streaming)(struct vb2_queue *q);
void (*buf_queue)(struct vb2_buffer *vb);
};
@@ -307,21 +352,31 @@ struct v4l2_fh;
* @buf_struct_size: size of the driver-specific buffer structure;
* "0" indicates the driver doesn't want to use a custom buffer
* structure type, so sizeof(struct vb2_buffer) will is used
+ * @timestamp_flags: Timestamp flags; V4L2_BUF_FLAGS_TIMESTAMP_* and
+ * V4L2_BUF_FLAGS_TSTAMP_SRC_*
* @gfp_flags: additional gfp flags used when allocating the buffers.
* Typically this is 0, but it may be e.g. GFP_DMA or __GFP_DMA32
* to force the buffer allocation to a specific memory zone.
+ * @min_buffers_needed: the minimum number of buffers needed before
+ * start_streaming() can be called. Used when a DMA engine
+ * cannot be started unless at least this number of buffers
+ * have been queued into the driver.
*
* @memory: current memory type used
* @bufs: videobuf buffer structures
* @num_buffers: number of allocated/used buffers
* @queued_list: list of buffers currently queued from userspace
- * @queued_count: number of buffers owned by the driver
+ * @queued_count: number of buffers queued and ready for streaming.
+ * @owned_by_drv_count: number of buffers owned by the driver
* @done_list: list of buffers ready to be dequeued to userspace
* @done_lock: lock to protect done_list list
* @done_wq: waitqueue for processes waiting for buffers ready to be dequeued
* @alloc_ctx: memory type/allocator-specific contexts for each plane
* @streaming: current streaming state
+ * @start_streaming_called: start_streaming() was called successfully and we
+ * started streaming.
* @fileio: file io emulator internal data, used only if emulator is active
+ * @threadio: thread io internal data, used only if thread is active
*/
struct vb2_queue {
enum v4l2_buf_type type;
@@ -334,8 +389,9 @@ struct vb2_queue {
const struct vb2_mem_ops *mem_ops;
void *drv_priv;
unsigned int buf_struct_size;
- u32 timestamp_type;
+ u32 timestamp_flags;
gfp_t gfp_flags;
+ u32 min_buffers_needed;
/* private: internal use only */
enum v4l2_memory memory;
@@ -343,8 +399,9 @@ struct vb2_queue {
unsigned int num_buffers;
struct list_head queued_list;
+ unsigned int queued_count;
- atomic_t queued_count;
+ atomic_t owned_by_drv_count;
struct list_head done_list;
spinlock_t done_lock;
wait_queue_head_t done_wq;
@@ -353,14 +410,29 @@ struct vb2_queue {
unsigned int plane_sizes[VIDEO_MAX_PLANES];
unsigned int streaming:1;
+ unsigned int start_streaming_called:1;
struct vb2_fileio_data *fileio;
+ struct vb2_threadio_data *threadio;
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+ /*
+ * Counters for how often these queue-related ops are
+ * called. Used to check for unbalanced ops.
+ */
+ u32 cnt_queue_setup;
+ u32 cnt_wait_prepare;
+ u32 cnt_wait_finish;
+ u32 cnt_start_streaming;
+ u32 cnt_stop_streaming;
+#endif
};
void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no);
void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no);
void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state);
+void vb2_discard_done(struct vb2_queue *q);
int vb2_wait_for_all_buffers(struct vb2_queue *q);
int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b);
@@ -391,8 +463,37 @@ unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait);
size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count,
loff_t *ppos, int nonblock);
-size_t vb2_write(struct vb2_queue *q, char __user *data, size_t count,
+size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count,
loff_t *ppos, int nonblock);
+/**
+ * vb2_thread_fnc - callback function for use with vb2_thread
+ *
+ * This is called whenever a buffer is dequeued in the thread.
+ */
+typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv);
+
+/**
+ * vb2_thread_start() - start a thread for the given queue.
+ * @q: videobuf queue
+ * @fnc: callback function
+ * @priv: priv pointer passed to the callback function
+ * @thread_name:the name of the thread. This will be prefixed with "vb2-".
+ *
+ * This starts a thread that will queue and dequeue until an error occurs
+ * or @vb2_thread_stop is called.
+ *
+ * This function should not be used for anything else but the videobuf2-dvb
+ * support. If you think you have another good use-case for this, then please
+ * contact the linux-media mailinglist first.
+ */
+int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv,
+ const char *thread_name);
+
+/**
+ * vb2_thread_stop() - stop the thread for the given queue.
+ * @q: videobuf queue
+ */
+int vb2_thread_stop(struct vb2_queue *q);
/**
* vb2_is_streaming() - return streaming status of the queue
@@ -404,6 +505,23 @@ static inline bool vb2_is_streaming(struct vb2_queue *q)
}
/**
+ * vb2_fileio_is_active() - return true if fileio is active.
+ * @q: videobuf queue
+ *
+ * This returns true if read() or write() is used to stream the data
+ * as opposed to stream I/O. This is almost never an important distinction,
+ * except in rare cases. One such case is that using read() or write() to
+ * stream a format using V4L2_FIELD_ALTERNATE is not allowed since there
+ * is no way you can pass the field information of each buffer to/from
+ * userspace. A driver that supports this field format should check for
+ * this in the queue_setup op and reject it if this function returns true.
+ */
+static inline bool vb2_fileio_is_active(struct vb2_queue *q)
+{
+ return q->fileio;
+}
+
+/**
* vb2_is_busy() - return busy status of the queue
* @q: videobuf queue
*
@@ -491,7 +609,8 @@ int vb2_ioctl_expbuf(struct file *file, void *priv,
int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma);
int vb2_fop_release(struct file *file);
-ssize_t vb2_fop_write(struct file *file, char __user *buf,
+int _vb2_fop_release(struct file *file, struct mutex *lock);
+ssize_t vb2_fop_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos);
ssize_t vb2_fop_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos);