@@ -49,6 +49,9 @@ config V4L2_MEM2MEM_DEV
tristate
depends on VIDEOBUF_GEN
+config VIDEOBUF2_CORE
+ tristate
+
#
# Multimedia Video device configuration
#
@@ -117,6 +117,8 @@ obj-$(CONFIG_VIDEOBUF_VMALLOC) += videobuf-vmalloc.o
obj-$(CONFIG_VIDEOBUF_DVB) += videobuf-dvb.o
obj-$(CONFIG_VIDEO_BTCX) += btcx-risc.o
+obj-$(CONFIG_VIDEOBUF2_CORE) += videobuf2-core.o
+
obj-$(CONFIG_V4L2_MEM2MEM_DEV) += v4l2-mem2mem.o
obj-$(CONFIG_VIDEO_M32R_AR_M64278) += arv.o
new file mode 100644
@@ -0,0 +1,1440 @@
+/*
+ * videobuf2-core.c - V4L2 driver helper framework
+ *
+ * Copyright (C) 2010 Samsung Electronics
+ *
+ * Author: Pawel Osciak <p.osciak@samsung.com>
+ * Marek Szyprowski <m.szyprowski@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <linux/poll.h>
+
+#include <media/videobuf2-core.h>
+
+static int debug;
+module_param(debug, int, 0644);
+
+#define dprintk(level, fmt, arg...) \
+ do { \
+ if (debug >= level) \
+ printk(KERN_DEBUG "vb2: " fmt, ## arg); \
+ } while (0)
+
+#define mem_ops(q, plane) ((q)->alloc_ctx[plane]->mem_ops)
+
+#define call_memop(q, plane, op, args...) \
+ (((q)->alloc_ctx[plane]->mem_ops->op) ? \
+ ((q)->alloc_ctx[plane]->mem_ops->op(args)) : 0)
+
+/**
+ * __vb2_buf_mem_alloc() - allocate video memory for the given buffer
+ */
+static int __vb2_buf_mem_alloc(struct vb2_buffer *vb,
+ unsigned long *plane_sizes)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+ void *mem_priv;
+ int plane;
+
+ /* Allocate memory for all planes in this buffer */
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ mem_priv = call_memop(q, plane, alloc, q->alloc_ctx[plane],
+ plane_sizes[plane]);
+ if (!mem_priv)
+ goto free;
+
+ /* Associate allocator private data with this plane */
+ vb->planes[plane].mem_priv = mem_priv;
+ vb->v4l2_planes[plane].length = plane_sizes[plane];
+ }
+
+ return 0;
+free:
+ /* Free already allocated memory if one of the allocations failed */
+ for (; plane > 0; --plane)
+ call_memop(q, plane, put, vb->planes[plane - 1].mem_priv);
+
+ return -ENOMEM;
+}
+
+/**
+ * __vb2_buf_mem_free() - free memory of the given buffer
+ */
+static void __vb2_buf_mem_free(struct vb2_buffer *vb)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+ unsigned int plane;
+
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ call_memop(q, plane, put, vb->planes[plane].mem_priv);
+ dprintk(3, "Freed plane %d of buffer %d\n",
+ plane, vb->v4l2_buf.index);
+ }
+}
+
+/**
+ * __vb2_buf_userptr_put() - release userspace memory associated associated
+ * with a USERPTR buffer
+ */
+static void __vb2_buf_userptr_put(struct vb2_buffer *vb)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+ unsigned int plane;
+
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ call_memop(q, plane, put_userptr, vb->planes[plane].mem_priv);
+ vb->planes[plane].mem_priv = NULL;
+ }
+}
+
+/**
+ * __setup_offsets() - setup unique offsets ("cookies") for every plane in
+ * every buffer on the queue
+ */
+static void __setup_offsets(struct vb2_queue *q)
+{
+ unsigned int buffer, plane;
+ struct vb2_buffer *vb;
+ unsigned long off = 0;
+
+ for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ vb = q->bufs[buffer];
+ if (!vb)
+ continue;
+
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ vb->v4l2_planes[plane].m.mem_offset = off;
+
+ dprintk(3, "Buffer %d, plane %d offset 0x%08lx\n",
+ buffer, plane, off);
+
+ off += vb->v4l2_planes[plane].length;
+ off = PAGE_ALIGN(off);
+ }
+ }
+}
+
+/**
+ * __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type)
+ * video buffer memory for all buffers/planes on the queue and initializes the
+ * queue
+ *
+ * Returns the number of buffers successfully allocated.
+ */
+static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
+ unsigned int num_buffers, unsigned int num_planes)
+{
+ unsigned long plane_sizes[VIDEO_MAX_PLANES];
+ unsigned int buffer, plane;
+ struct vb2_buffer *vb;
+ int ret;
+
+ /* Get requested plane sizes from the driver */
+ for (plane = 0; plane < num_planes; ++plane) {
+ ret = q->ops->plane_setup(q, plane, &plane_sizes[plane]);
+ if (ret) {
+ dprintk(1, "Plane setup failed\n");
+ return ret;
+ }
+ }
+
+ for (buffer = 0; buffer < num_buffers; ++buffer) {
+ /* Allocate videobuf buffer structures */
+ vb = kzalloc(sizeof(struct vb2_buffer), GFP_KERNEL);
+ if (!vb) {
+ dprintk(1, "Memory alloc for buffer struct failed\n");
+ break;
+ }
+
+ /* Length stores number of planes for multiplanar buffers */
+ if (V4L2_TYPE_IS_MULTIPLANAR(q->type))
+ vb->v4l2_buf.length = num_planes;
+
+ vb->state = VB2_BUF_STATE_DEQUEUED;
+ vb->vb2_queue = q;
+ vb->num_planes = num_planes;
+ vb->v4l2_buf.index = buffer;
+ vb->v4l2_buf.type = q->type;
+ vb->v4l2_buf.memory = memory;
+
+ /* Allocate video buffer memory for the MMAP type */
+ if (memory == V4L2_MEMORY_MMAP) {
+ ret = __vb2_buf_mem_alloc(vb, plane_sizes);
+ if (ret) {
+ dprintk(1, "Failed allocating memory for "
+ "buffer %d\n", buffer);
+ kfree(vb);
+ break;
+ }
+ /*
+ * Call the driver-provided buffer initialization
+ * callback, if given. An error in initialization
+ * results in queue setup failure.
+ */
+ if (q->ops->buf_init) {
+ ret = q->ops->buf_init(vb);
+ if (ret) {
+ dprintk(1, "Buffer %d %p initialization"
+ " failed\n", buffer, vb);
+ __vb2_buf_mem_free(vb);
+ kfree(vb);
+ break;
+ }
+ }
+ }
+
+ q->bufs[buffer] = vb;
+ }
+
+ q->num_buffers = buffer;
+
+ __setup_offsets(q);
+
+ dprintk(1, "Allocated %d buffers, %d plane(s) each\n",
+ q->num_buffers, num_planes);
+
+ return buffer;
+}
+
+/**
+ * __vb2_free_mem() - release all video buffer memory for a given queue
+ */
+static void __vb2_free_mem(struct vb2_queue *q)
+{
+ unsigned int buffer;
+ struct vb2_buffer *vb;
+
+ for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ vb = q->bufs[buffer];
+ if (!vb)
+ continue;
+
+ /* Free MMAP buffers or release USERPTR buffers */
+ if (q->memory == V4L2_MEMORY_MMAP)
+ __vb2_buf_mem_free(vb);
+ else
+ __vb2_buf_userptr_put(vb);
+ }
+}
+
+/**
+ * __vb2_queue_free() - free the queue - video memory and related information
+ * and return the queue to an uninitialized state
+ */
+static int __vb2_queue_free(struct vb2_queue *q)
+{
+ unsigned int buffer;
+
+ /* Call driver-provided cleanup function for each buffer, if provided */
+ if (q->ops->buf_cleanup) {
+ for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ if (NULL == q->bufs[buffer])
+ continue;
+ q->ops->buf_cleanup(q->bufs[buffer]);
+ }
+ }
+
+ /* Release video buffer memory */
+ __vb2_free_mem(q);
+
+ /* Free videobuf buffers */
+ for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ if (NULL == q->bufs[buffer])
+ continue;
+ kfree(q->bufs[buffer]);
+ q->bufs[buffer] = NULL;
+ }
+
+ q->num_buffers = 0;
+ q->memory = 0;
+
+ return 0;
+}
+
+/**
+ * __verify_planes_array() - verify that the planes array passed in struct
+ * v4l2_buffer from userspace can be safely used
+ */
+static int __verify_planes_array(struct vb2_buffer *vb, struct v4l2_buffer *b)
+{
+ /* Is memory for copying plane information present? */
+ if (NULL == b->m.planes) {
+ dprintk(1, "Multi-planar buffer passed but "
+ "planes array not provided\n");
+ return -EINVAL;
+ }
+
+ if (b->length < vb->num_planes || b->length > VIDEO_MAX_PLANES) {
+ dprintk(1, "Incorrect planes array length, "
+ "expected %d, got %d\n", vb->num_planes, b->length);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be
+ * returned to userspace
+ */
+static int __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+ int ret = 0;
+
+ /* Copy back data such as timestamp, input, etc. */
+ memcpy(b, &vb->v4l2_buf, offsetof(struct v4l2_buffer, m));
+ b->input = vb->v4l2_buf.input;
+ b->reserved = vb->v4l2_buf.reserved;
+
+ if (V4L2_TYPE_IS_MULTIPLANAR(q->type)) {
+ ret = __verify_planes_array(vb, b);
+ if (ret)
+ return ret;
+
+ /*
+ * Fill in plane-related data if userspace provided an array
+ * for it. The memory and size is verified above.
+ */
+ memcpy(b->m.planes, vb->v4l2_planes,
+ b->length * sizeof(struct v4l2_plane));
+ } else {
+ /*
+ * We use length and offset in v4l2_planes array even for
+ * single-planar buffers, but userspace does not.
+ */
+ b->length = vb->v4l2_planes[0].length;
+ if (q->memory == V4L2_MEMORY_MMAP)
+ b->m.offset = vb->v4l2_planes[0].m.mem_offset;
+ }
+
+ b->flags = 0;
+
+ switch (vb->state) {
+ case VB2_BUF_STATE_QUEUED:
+ case VB2_BUF_STATE_ACTIVE:
+ b->flags |= V4L2_BUF_FLAG_QUEUED;
+ break;
+ case VB2_BUF_STATE_ERROR:
+ b->flags |= V4L2_BUF_FLAG_ERROR;
+ /* fall through */
+ case VB2_BUF_STATE_DONE:
+ b->flags |= V4L2_BUF_FLAG_DONE;
+ break;
+ case VB2_BUF_STATE_DEQUEUED:
+ /* nothing */
+ break;
+ }
+
+ if (vb->num_planes_mapped == vb->num_planes)
+ b->flags |= V4L2_BUF_FLAG_MAPPED;
+
+ return ret;
+}
+
+/**
+ * vb2_querybuf() - query video buffer information
+ * @q: videobuf queue
+ * @b: buffer struct passed from userspace to vidioc_querybuf handler
+ * in driver
+ *
+ * Should be called from vidioc_querybuf ioctl handler in driver.
+ * This function will verify the passed v4l2_buffer structure and fill the
+ * relevant information for the userspace.
+ *
+ * The return values from this function are intended to be directly returned
+ * from vidioc_querybuf handler in driver.
+ */
+int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
+{
+ struct vb2_buffer *vb;
+ int ret = -EINVAL;
+
+ mutex_lock(&q->vb_lock);
+
+ if (b->type != q->type) {
+ dprintk(1, "querybuf: wrong buffer type\n");
+ goto done;
+ }
+
+ if (b->index >= q->num_buffers) {
+ dprintk(1, "querybuf: buffer index out of range\n");
+ goto done;
+ }
+ vb = q->bufs[b->index];
+ if (NULL == vb) {
+ /* Should never happen */
+ dprintk(1, "querybuf: no such buffer\n");
+ goto done;
+ }
+
+ ret = __fill_v4l2_buffer(vb, b);
+done:
+ mutex_unlock(&q->vb_lock);
+ return ret;
+}
+EXPORT_SYMBOL(vb2_querybuf);
+
+/**
+ * __verify_userptr_ops() - verify that all memory operations required for
+ * USERPTR queue type have been provided
+ */
+static int __verify_userptr_ops(struct vb2_queue *q, unsigned int num_planes)
+{
+ unsigned int i;
+
+ for (i = 0; i < num_planes; ++i)
+ if (!mem_ops(q, i)->get_userptr || !mem_ops(q, i)->put_userptr)
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * __verify_mmap_ops() - verify that all memory operations required for
+ * MMAP queue type have been provided
+ */
+static int __verify_mmap_ops(struct vb2_queue *q, unsigned int num_planes)
+{
+ unsigned int i;
+
+ for (i = 0; i < num_planes; ++i)
+ if (!mem_ops(q, i)->alloc || !mem_ops(q, i)->put
+ || !mem_ops(q, i)->mmap)
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * __buffers_in_use() - return true if any buffers on the queue are in use and
+ * the queue cannot be freed (by the means of REQBUFS(0)) call
+ */
+static bool __buffers_in_use(struct vb2_queue *q)
+{
+ unsigned int buffer, plane;
+ struct vb2_buffer *vb;
+
+ for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ vb = q->bufs[buffer];
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ /*
+ * If num_users() has not been provided, apparently
+ * nobody cares.
+ */
+ if (!mem_ops(q, plane)->num_users)
+ continue;
+
+ /*
+ * If num_users() returns more than 1, we are not the
+ * only user of the plane's memory.
+ */
+ if (call_memop(q, plane, num_users,
+ vb->planes[plane].mem_priv) > 1)
+ return true;
+ }
+ }
+
+ return false;
+}
+
+/**
+ * vb2_reqbufs() - Initiate streaming
+ * @q: videobuf2 queue
+ * @req: struct passed from userspace to vidioc_reqbufs handler in driver
+ *
+ * Should be called from vidioc_reqbufs ioctl handler of a driver.
+ * This function:
+ * 1) verifies streaming parameters passed from the userspace,
+ * 2) sets up the queue,
+ * 3) negotiates number of buffers and planes per buffer with the driver
+ * to be used during streaming,
+ * 4) allocates internal buffer structures (struct vb2_buffer), according to
+ * the agreed parameters,
+ * 5) for MMAP memory type, allocates actual video memory, using the
+ * memory handling/allocation routines provided during queue initialization
+ *
+ * If req->count is 0, all the memory will be freed instead.
+ * If the queue has been allocated previously (by a previous vb2_reqbufs) call
+ * and the queue is not busy, memory will be reallocated.
+ *
+ * The return values from this function are intended to be directly returned
+ * from vidioc_reqbufs handler in driver.
+ */
+int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
+{
+ unsigned int num_buffers, num_planes;
+ int ret = 0;
+
+ if (req->memory != V4L2_MEMORY_MMAP
+ && req->memory != V4L2_MEMORY_USERPTR) {
+ dprintk(1, "reqbufs: unsupported memory type\n");
+ return -EINVAL;
+ }
+
+ mutex_lock(&q->vb_lock);
+
+ if (req->type != q->type) {
+ dprintk(1, "reqbufs: queue type invalid\n");
+ ret = -EINVAL;
+ goto end;
+ }
+
+ if (q->streaming) {
+ dprintk(1, "reqbufs: streaming active\n");
+ ret = -EBUSY;
+ goto end;
+ }
+
+ if (req->count == 0) {
+ /* Free/release memory for count = 0, but only if unused */
+ if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) {
+ dprintk(1, "reqbufs: memory in use, cannot free\n");
+ ret = -EBUSY;
+ goto end;
+ }
+
+ ret = __vb2_queue_free(q);
+ goto end;
+ }
+
+ if (q->num_buffers != 0) {
+ /*
+ * We already have buffers allocated, so a reallocation is
+ * required, but only if the buffers are not in use.
+ */
+ if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) {
+ dprintk(1, "reqbufs: memory in use, "
+ "cannot reallocate\n");
+ ret = -EBUSY;
+ goto end;
+ }
+
+ ret = __vb2_queue_free(q);
+ if (ret)
+ goto end;
+ }
+
+ num_buffers = min_t(unsigned int, req->count, VIDEO_MAX_FRAME);
+
+ /* Ask the driver how many buffers and planes per buffer it requires */
+ ret = q->ops->queue_negotiate(q, &num_buffers, &num_planes);
+ if (ret)
+ goto end;
+
+ /*
+ * Make sure all the required memory ops for given memory type
+ * are available.
+ */
+ if (req->memory == V4L2_MEMORY_MMAP
+ && __verify_mmap_ops(q, num_planes)) {
+ dprintk(1, "reqbufs: MMAP for current setup unsupported\n");
+ ret = -EINVAL;
+ goto end;
+ } else if (req->memory == V4L2_MEMORY_USERPTR
+ && __verify_userptr_ops(q, num_planes)) {
+ dprintk(1, "reqbufs: USERPTR for current setup unsupported\n");
+ ret = -EINVAL;
+ goto end;
+ }
+
+ /* Finally, allocate buffers and video memory */
+ ret = __vb2_queue_alloc(q, req->memory, num_buffers, num_planes);
+ if (ret < 0) {
+ dprintk(1, "Memory allocation failed with error: %d\n", ret);
+ } else {
+ /*
+ * Return the number of successfully allocated buffers
+ * to the userspace.
+ */
+ req->count = ret;
+ ret = 0;
+ }
+
+ q->memory = req->memory;
+
+end:
+ mutex_unlock(&q->vb_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vb2_reqbufs);
+
+/**
+ * vb2_plane_vaddr() - Return a kernel virtual address of a given plane
+ * @vb: vb2_buffer to which the plane in question belongs to
+ * @plane_no: plane number for which the address is to be returned
+ *
+ * This function returns a kernel virtual address of a given plane if
+ * such a mapping exist, NULL otherwise.
+ */
+void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+
+ if (plane_no > vb->num_planes)
+ return NULL;
+
+ return call_memop(q, plane_no, vaddr, vb->planes[plane_no].mem_priv);
+
+}
+EXPORT_SYMBOL_GPL(vb2_plane_vaddr);
+
+/**
+ * vb2_plane_paddr() - Return the physical address of a given plane
+ * @vb: vb2_buffer to which the plane in question belongs to
+ * @plane_no: plane number for which the address is to be returned
+ *
+ * This function returns a physical address of a given plane if available,
+ * NULL otherwise.
+ */
+unsigned long vb2_plane_paddr(struct vb2_buffer *vb, unsigned int plane_no)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+
+ if (plane_no > vb->num_planes)
+ return 0UL;
+
+ return call_memop(q, plane_no, paddr, vb->planes[plane_no].mem_priv);
+}
+EXPORT_SYMBOL_GPL(vb2_plane_paddr);
+
+/**
+ * vb2_buffer_done() - inform videobuf that an operation on a buffer is finished
+ * @vb: vb2_buffer returned from the driver
+ * @state: either VB2_BUF_STATE_DONE if the operation finished successfully
+ * or VB2_BUF_STATE_ERROR if the operation finished with an error
+ *
+ * This function should be called by the driver after a hardware operation on
+ * a buffer is finished and the buffer may be returned to userspace. The driver
+ * cannot use this buffer anymore until it is queued back to it by videobuf
+ * by the means of buf_queue callback. Only buffers previously queued to the
+ * driver by buf_queue can be passed to this function.
+ */
+void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+ unsigned long flags;
+
+ if (vb->state != VB2_BUF_STATE_ACTIVE)
+ return;
+
+ if (state != VB2_BUF_STATE_DONE && state != VB2_BUF_STATE_ERROR)
+ return;
+
+ dprintk(4, "Done processing on buffer %d, state: %d\n",
+ vb->v4l2_buf.index, vb->state);
+
+ /* Add the buffer to the done buffers list */
+ spin_lock_irqsave(&q->done_lock, flags);
+ vb->state = state;
+ list_add_tail(&vb->done_entry, &q->done_list);
+ spin_unlock_irqrestore(&q->done_lock, flags);
+
+ /* Inform any processes that may be waiting for buffers */
+ wake_up(&q->done_wq);
+}
+EXPORT_SYMBOL_GPL(vb2_buffer_done);
+
+/**
+ * __fill_vb2_buffer() - fill a vb2_buffer with information provided in
+ * a v4l2_buffer by the userspace
+ */
+static int __fill_vb2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b,
+ struct v4l2_plane *v4l2_planes)
+{
+ unsigned int plane;
+ int ret;
+
+ if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) {
+ /*
+ * Verify that the userspace gave us a valid array for
+ * plane information.
+ */
+ ret = __verify_planes_array(vb, b);
+ if (ret)
+ return ret;
+
+ /* Fill in driver-provided information for OUTPUT types */
+ if (V4L2_TYPE_IS_OUTPUT(b->type)) {
+ /*
+ * Will have to go up to b->length when API starts
+ * accepting variable number of planes.
+ */
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ v4l2_planes[plane].bytesused =
+ b->m.planes[plane].bytesused;
+ v4l2_planes[plane].data_offset =
+ b->m.planes[plane].data_offset;
+ }
+ }
+
+ if (b->memory == V4L2_MEMORY_USERPTR) {
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ v4l2_planes[plane].m.userptr =
+ b->m.planes[plane].m.userptr;
+ v4l2_planes[plane].length =
+ b->m.planes[plane].length;
+ }
+ }
+ } else {
+ /*
+ * Single-planar buffers do not use planes array,
+ * so fill in relevant v4l2_buffer struct fields instead.
+ * In videobuf we use our internal V4l2_planes struct for
+ * single-planar buffers as well, for simplicity.
+ */
+ if (V4L2_TYPE_IS_OUTPUT(b->type))
+ v4l2_planes[0].bytesused = b->bytesused;
+
+ if (b->memory == V4L2_MEMORY_USERPTR) {
+ v4l2_planes[0].m.userptr = b->m.userptr;
+ v4l2_planes[0].length = b->length;
+ }
+ }
+
+ vb->v4l2_buf.field = b->field;
+ vb->v4l2_buf.timestamp = b->timestamp;
+
+ return 0;
+}
+
+/**
+ * __qbuf_userptr() - handle qbuf of a USERPTR buffer
+ */
+static int __qbuf_userptr(struct vb2_buffer *vb, struct v4l2_buffer *b)
+{
+ struct v4l2_plane planes[VIDEO_MAX_PLANES];
+ struct vb2_queue *q = vb->vb2_queue;
+ void *mem_priv = NULL;
+ unsigned int plane;
+ int ret;
+
+ /* Verify and copy relevant information provided by the userspace */
+ ret = __fill_vb2_buffer(vb, b, planes);
+ if (ret)
+ return ret;
+
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ /* Skip the plane if already verified */
+ if (vb->v4l2_planes[plane].m.userptr == planes[plane].m.userptr
+ && vb->v4l2_planes[plane].length == planes[plane].length)
+ continue;
+
+ dprintk(3, "qbuf: userspace address for plane %d changed, "
+ "reacquiring memory\n", plane);
+
+ /* Release previously acquired memory if present */
+ if (vb->planes[plane].mem_priv)
+ call_memop(q, plane, put_userptr,
+ vb->planes[plane].mem_priv);
+
+ vb->planes[plane].mem_priv = NULL;
+
+ /* Acquire each plane's memory */
+ if (mem_ops(q, plane)->get_userptr) {
+ mem_priv = mem_ops(q, plane)->get_userptr(
+ planes[plane].m.userptr,
+ planes[plane].length);
+ if (IS_ERR(mem_priv)) {
+ dprintk(1, "qbuf: failed acquiring userspace "
+ "memory for plane %d\n", plane);
+ goto err;
+ }
+
+ vb->planes[plane].mem_priv = mem_priv;
+ }
+ }
+
+ /*
+ * Call driver-specific initialization on the newly acquired buffer,
+ * if provided.
+ */
+ if (q->ops->buf_init) {
+ ret = q->ops->buf_init(vb);
+ if (ret) {
+ dprintk(1, "qbuf: buffer initialization failed\n");
+ goto err;
+ }
+ }
+
+ /*
+ * Now that everything is in order, copy relevant information
+ * provided by userspace.
+ */
+ for (plane = 0; plane < vb->num_planes; ++plane)
+ vb->v4l2_planes[plane] = planes[plane];
+
+ return 0;
+err:
+ /* In case of errors, release planes that were already acquired */
+ for (; plane > 0; --plane) {
+ call_memop(q, plane, put_userptr,
+ vb->planes[plane - 1].mem_priv);
+ vb->planes[plane - 1].mem_priv = NULL;
+ }
+
+ return ret;
+}
+
+/**
+ * __qbuf_mmap() - handle qbuf of an MMAP buffer
+ */
+static int __qbuf_mmap(struct vb2_buffer *vb, struct v4l2_buffer *b)
+{
+ return __fill_vb2_buffer(vb, b, vb->v4l2_planes);
+}
+
+/**
+ * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing
+ */
+static void __enqueue_in_driver(struct vb2_buffer *vb)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+ vb->state = VB2_BUF_STATE_ACTIVE;
+ q->ops->buf_queue(vb);
+}
+
+/**
+ * vb2_qbuf() - Queue a buffer from userspace
+ * @q: videobuf2 queue
+ * @b: buffer structure passed from userspace to vidioc_qbuf handler
+ * in driver
+ *
+ * Should be called from vidioc_qbuf ioctl handler of a driver.
+ * This function:
+ * 1) verifies the passed buffer,
+ * 2) calls buf_prepare callback in the driver (if provided), in which
+ * driver-specific buffer initialization can be performed,
+ * 3) if streaming is on, queues the buffer in driver by the means of buf_queue
+ * callback for processing.
+ *
+ * The return values from this function are intended to be directly returned
+ * from vidioc_qbuf handler in driver.
+ */
+int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
+{
+ struct vb2_buffer *vb;
+ int ret;
+
+ mutex_lock(&q->vb_lock);
+
+ ret = -EINVAL;
+ if (b->type != q->type) {
+ dprintk(1, "qbuf: invalid buffer type\n");
+ goto done;
+ }
+ if (b->index >= q->num_buffers) {
+ dprintk(1, "qbuf: buffer index out of range\n");
+ goto done;
+ }
+
+ vb = q->bufs[b->index];
+ if (NULL == vb) {
+ /* Should never happen */
+ dprintk(1, "qbuf: buffer is NULL\n");
+ goto done;
+ }
+
+ if (b->memory != q->memory) {
+ dprintk(1, "qbuf: invalid memory type\n");
+ goto done;
+ }
+
+ if (vb->state != VB2_BUF_STATE_DEQUEUED) {
+ dprintk(1, "qbuf: buffer already in use\n");
+ goto done;
+ }
+
+ if (q->memory == V4L2_MEMORY_MMAP)
+ ret = __qbuf_mmap(vb, b);
+ else if (q->memory == V4L2_MEMORY_USERPTR)
+ ret = __qbuf_userptr(vb, b);
+ if (ret)
+ goto done;
+
+ if (q->ops->buf_prepare) {
+ ret = q->ops->buf_prepare(vb);
+ if (ret) {
+ dprintk(1, "qbuf: buffer preparation failed\n");
+ goto done;
+ }
+ }
+
+ /*
+ * Add to the queued buffers list, a buffer will stay on it until
+ * dequeued in dqbuf.
+ */
+ list_add_tail(&vb->queued_entry, &q->queued_list);
+ vb->state = VB2_BUF_STATE_QUEUED;
+
+ /*
+ * If already streaming, give the buffer to driver for processing.
+ * If not, the buffer will be given to driver on next streamon.
+ */
+ if (q->streaming)
+ __enqueue_in_driver(vb);
+
+ dprintk(1, "qbuf of buffer %d succeeded\n", vb->v4l2_buf.index);
+ ret = 0;
+done:
+ mutex_unlock(&q->vb_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vb2_qbuf);
+
+/**
+ * __vb2_wait_for_done_vb() - wait for a buffer to become available
+ * for dequeuing
+ *
+ * Will sleep if required for nonblocking == false.
+ */
+static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking)
+{
+checks:
+ if (!q->streaming) {
+ dprintk(1, "Streaming off, will not wait for buffers\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Buffers may be added to vb_done_list without holding the vb_lock,
+ * but removal is performed only while holding both vb_lock and the
+ * vb_done_lock spinlock. Thus we can be sure that as long as we hold
+ * vb_lock, the list will remain not empty if this check succeeds.
+ */
+ if (list_empty(&q->done_list)) {
+ int retval;
+ if (nonblocking) {
+ dprintk(1, "Nonblocking and no buffers to dequeue, "
+ "will not wait\n");
+ return -EAGAIN;
+ }
+
+ /*
+ * We are streaming and nonblocking, wait for another buffer to
+ * become ready or for streamoff. vb_lock is released to allow
+ * streamoff or qbuf to be called while waiting.
+ */
+ mutex_unlock(&q->vb_lock);
+ /*
+ * Although the mutex is released here, we will be reevaluating
+ * both conditions again after reacquiring it.
+ */
+ dprintk(3, "Will sleep waiting for buffers\n");
+ retval = wait_event_interruptible(q->done_wq,
+ !list_empty(&q->done_list) || !q->streaming);
+ mutex_lock(&q->vb_lock);
+
+ if (retval)
+ return -EINTR;
+
+ goto checks;
+ }
+ return 0;
+}
+
+/**
+ * __vb2_get_done_vb() - get a buffer ready for dequeuing
+ *
+ * Will sleep if required for nonblocking == false.
+ */
+static int __vb2_get_done_vb(struct vb2_queue *q, struct vb2_buffer **vb,
+ int nonblocking)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ /*
+ * Wait for at least one buffer to become available on the done_list.
+ */
+ ret = __vb2_wait_for_done_vb(q, nonblocking);
+ if (ret)
+ goto end;
+
+ /*
+ * vb_lock has been held since we last verified that done_list is
+ * not empty, so no need for another list_empty(done_list) check.
+ */
+ spin_lock_irqsave(&q->done_lock, flags);
+ *vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry);
+ list_del(&(*vb)->done_entry);
+ spin_unlock_irqrestore(&q->done_lock, flags);
+
+end:
+ return ret;
+}
+
+
+/**
+ * vb2_dqbuf() - Dequeue a buffer to the userspace
+ * @q: videobuf2 queue
+ * @b: buffer structure passed from userspace to vidioc_dqbuf handler
+ * in driver
+ * @nonblocking: if true, this call will not sleep waiting for a buffer if no
+ * buffers ready for dequeuing are present. Normally the driver
+ * would be passing (file->f_flags & O_NONBLOCK) here
+ *
+ * Should be called from vidioc_dqbuf ioctl handler of a driver.
+ * This function:
+ * 1) verifies the passed buffer,
+ * 2) calls buf_finish callback in the driver (if provided), in which
+ * driver can perform any additional operations that may be required before
+ * returning the buffer to userspace, such as cache sync,
+ * 3) the buffer struct members are filled with relevant information for
+ * the userspace.
+ *
+ * The return values from this function are intended to be directly returned
+ * from vidioc_dqbuf handler in driver.
+ */
+int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking)
+{
+ struct vb2_buffer *vb = NULL;
+ int ret;
+
+ mutex_lock(&q->vb_lock);
+
+ if (b->type != q->type) {
+ dprintk(1, "dqbuf: invalid buffer type\n");
+ ret = -EINVAL;
+ goto done;
+ }
+
+ ret = __vb2_get_done_vb(q, &vb, nonblocking);
+ if (ret < 0) {
+ dprintk(1, "dqbuf: error getting next done buffer\n");
+ goto done;
+ }
+
+ if (q->ops->buf_finish) {
+ ret = q->ops->buf_finish(vb);
+ if (ret) {
+ dprintk(1, "dqbuf: buffer finish failed\n");
+ goto done;
+ }
+ }
+
+ switch (vb->state) {
+ case VB2_BUF_STATE_DONE:
+ dprintk(3, "dqbuf: Returning done buffer\n");
+ break;
+ case VB2_BUF_STATE_ERROR:
+ dprintk(3, "dqbuf: Returning done buffer with errors\n");
+ break;
+ default:
+ dprintk(1, "dqbuf: Invalid buffer state\n");
+ ret = -EINVAL;
+ goto done;
+ }
+
+ /* Fill buffer information for the userspace */
+ __fill_v4l2_buffer(vb, b);
+ /* Remove from videobuf queue */
+ list_del(&vb->queued_entry);
+
+ dprintk(1, "dqbuf of buffer %d, with state %d\n",
+ vb->v4l2_buf.index, vb->state);
+
+ vb->state = VB2_BUF_STATE_DEQUEUED;
+
+done:
+ mutex_unlock(&q->vb_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vb2_dqbuf);
+
+/**
+ * vb2_streamon - start streaming
+ * @q: videobuf2 queue
+ * @type: type argument passed from userspace to vidioc_streamon handler
+ *
+ * Should be called from vidioc_streamon handler of a driver.
+ * This function:
+ * 1) verifies current state
+ * 2) starts streaming and passes any previously queued buffers to the driver
+ *
+ * The return values from this function are intended to be directly returned
+ * from vidioc_streamon handler in the driver.
+ */
+int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
+{
+ struct vb2_buffer *vb;
+ int ret = 0;
+
+ mutex_lock(&q->vb_lock);
+
+ if (type != q->type) {
+ dprintk(1, "streamon: invalid stream type\n");
+ ret = -EINVAL;
+ goto done;
+ }
+
+ if (q->streaming) {
+ dprintk(1, "streamon: already streaming\n");
+ ret = -EBUSY;
+ goto done;
+ }
+
+ /*
+ * Cannot start streaming on an OUTPUT device if no buffers have
+ * been queued yet.
+ */
+ if (V4L2_TYPE_IS_OUTPUT(q->type)) {
+ if (list_empty(&q->queued_list)) {
+ dprintk(1, "streamon: no output buffers queued\n");
+ ret = -EINVAL;
+ goto done;
+ }
+ }
+
+ q->streaming = 1;
+
+ /*
+ * Let driver notice that streaming state has been enabled.
+ */
+ if (q->ops->start_streaming)
+ q->ops->start_streaming(q);
+
+ /*
+ * If any buffers were queued before streamon,
+ * we can now pass them to driver for processing.
+ */
+ list_for_each_entry(vb, &q->queued_list, queued_entry)
+ __enqueue_in_driver(vb);
+
+ dprintk(3, "Streamon successful\n");
+done:
+ mutex_unlock(&q->vb_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vb2_streamon);
+
+/**
+ * __vb2_queue_cancel() - cancel and stop (pause) streaming
+ *
+ * Removes all queued buffers from driver's queue and all buffers queued by
+ * userspace from videobuf's queue. Returns to state after reqbufs.
+ */
+static void __vb2_queue_cancel(struct vb2_queue *q)
+{
+ /*
+ * Tell driver to stop all dma transactions and release all queued
+ * buffers
+ */
+ if (q->streaming && q->ops->stop_streaming)
+ q->ops->stop_streaming(q);
+ q->streaming = 0;
+
+ /*
+ * Remove all buffers from videobuf's list...
+ */
+ INIT_LIST_HEAD(&q->queued_list);
+ /*
+ * ...and done list; userspace will not receive any buffers it
+ * has not already dequeued before initiating cancel.
+ */
+ INIT_LIST_HEAD(&q->done_list);
+ wake_up_all(&q->done_wq);
+}
+
+/**
+ * vb2_streamoff - stop streaming
+ * @q: videobuf2 queue
+ * @type: type argument passed from userspace to vidioc_streamoff handler
+ *
+ * Should be called from vidioc_streamoff handler of a driver.
+ * This function:
+ * 1) verifies current state,
+ * 2) stop streaming and dequeues any queued buffers, including those previously
+ * passed to the driver (after waiting for the driver to finish).
+ *
+ * This call can be used for pausing playback.
+ * The return values from this function are intended to be directly returned
+ * from vidioc_streamoff handler in the driver
+ */
+int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type)
+{
+ int ret = 0;
+
+ mutex_lock(&q->vb_lock);
+
+ if (type != q->type) {
+ dprintk(1, "streamoff: invalid stream type\n");
+ ret = -EINVAL;
+ goto end;
+ }
+
+ if (!q->streaming) {
+ dprintk(1, "streamoff: not streaming\n");
+ ret = -EINVAL;
+ goto end;
+ }
+
+ /*
+ * Cancel will pause streaming and remove all buffers from the driver
+ * and videobuf, effectively returning control over them to userspace.
+ */
+ __vb2_queue_cancel(q);
+
+ dprintk(3, "Streamoff successful\n");
+end:
+ mutex_unlock(&q->vb_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vb2_streamoff);
+
+/**
+ * __find_plane_by_off() - find plane associated with the given offset off
+ */
+int __find_plane_by_off(struct vb2_queue *q, unsigned long off,
+ unsigned int *_buffer, unsigned int *_plane)
+{
+ struct vb2_buffer *vb;
+ unsigned int buffer, plane;
+
+ /*
+ * Go over all buffers and their planes, comparing the given offset
+ * with an offset assigned to each plane. If a match is found,
+ * return its buffer and plane numbers.
+ */
+ for (buffer = 0; buffer < q->num_buffers; ++buffer) {
+ vb = q->bufs[buffer];
+
+ for (plane = 0; plane < vb->num_planes; ++plane) {
+ if (vb->v4l2_planes[plane].m.mem_offset == off) {
+ *_buffer = buffer;
+ *_plane = plane;
+ return 0;
+ }
+ }
+ }
+
+ return -EINVAL;
+}
+
+/**
+ * vb2_mmap() - map video buffers into application address space
+ * @q: videobuf2 queue
+ * @vma: vma passed to the mmap file operation handler in the driver
+ *
+ * Should be called from mmap file operation handler of a driver.
+ * This function maps one plane of one of the available video buffers to
+ * userspace. To map whole video memory allocated on reqbufs, this function
+ * has to be called once per each plane per each buffer previously allocated.
+ *
+ * When the userspace application calls mmap, it passes to it an offset returned
+ * to it earlier by the means of vidioc_querybuf handler. That offset acts as
+ * a "cookie", which is then used to identify the plane to be mapped.
+ * This function finds a plane with a matching offset and a mapping is performed
+ * by the means of a provided memory operation.
+ *
+ * The return values from this function are intended to be directly returned
+ * from the mmap handler in driver.
+ */
+int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
+{
+ unsigned long off = vma->vm_pgoff << PAGE_SHIFT;
+ struct vb2_plane *vb_plane;
+ struct vb2_buffer *vb;
+ unsigned int buffer, plane;
+ int ret = -EINVAL;
+
+ if (q->memory != V4L2_MEMORY_MMAP) {
+ dprintk(1, "Queue is not currently set up for mmap\n");
+ return ret;
+ }
+
+ if (V4L2_TYPE_IS_OUTPUT(q->type) &&
+ (!(vma->vm_flags & VM_WRITE) || !(vma->vm_flags & VM_SHARED))) {
+ dprintk(1, "Invalid vma flags (need VM_WRITE | VM_SHARED)\n");
+ return ret;
+ } else if (!(vma->vm_flags & VM_READ) || !(vma->vm_flags & VM_SHARED)) {
+ dprintk(1, "Invalid vma flags (need VM_READ | VM_SHARED)\n");
+ return ret;
+ }
+
+ mutex_lock(&q->vb_lock);
+
+ /*
+ * Find the plane corresponding to the offset passed by userspace.
+ */
+ ret = __find_plane_by_off(q, off, &buffer, &plane);
+ if (ret)
+ goto end;
+
+ vb = q->bufs[buffer];
+ vb_plane = &vb->planes[plane];
+
+ if (vb_plane->mapped) {
+ dprintk(1, "Plane already mapped\n");
+ goto end;
+ }
+
+ if (!mem_ops(q, plane)->mmap) {
+ dprintk(1, "mmap not supported\n");
+ goto end;
+ }
+
+ ret = mem_ops(q, plane)->mmap(vb_plane->mem_priv, vma);
+ if (ret)
+ goto end;
+
+ vb_plane->mapped = 1;
+ vb->num_planes_mapped++;
+
+ dprintk(3, "Buffer %d, plane %d successfully mapped\n", buffer, plane);
+end:
+ mutex_unlock(&q->vb_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vb2_mmap);
+
+/**
+ * vb2_has_consumers() - return true if the userspace is waiting for a buffer
+ * @q: videobuf2 queue
+ *
+ * This function returns true if a userspace application is waiting for a buffer
+ * to be ready to dequeue (on which a hardware operation has been finished).
+ */
+bool vb2_has_consumers(struct vb2_queue *q)
+{
+ return waitqueue_active(&q->done_wq);
+}
+EXPORT_SYMBOL_GPL(vb2_has_consumers);
+
+/**
+ * vb2_poll() - implements poll userspace operation
+ * @q: videobuf2 queue
+ * @file: file argument passed to the poll file operation handler
+ * @wait: wait argument passed to the poll file operation handler
+ *
+ * This function implements poll file operation handler for a driver.
+ * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will
+ * be informed that the file descriptor of a video device is available for
+ * reading.
+ * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor
+ * will be reported as available for writing.
+ *
+ * The return values from this function are intended to be directly returned
+ * from poll handler in driver.
+ */
+unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
+{
+ unsigned long flags = 0;
+ unsigned int ret = 0;
+ struct vb2_buffer *vb = NULL;
+
+ mutex_lock(&q->vb_lock);
+
+ /*
+ * There is nothing to wait for if no buffers have already been queued.
+ */
+ if (list_empty(&q->queued_list)) {
+ ret = POLLERR;
+ goto end;
+ }
+
+ poll_wait(file, &q->done_wq, wait);
+
+ /*
+ * Take first buffer available for dequeuing.
+ */
+ spin_lock_irqsave(&q->done_lock, flags);
+ if (!list_empty(&q->done_list))
+ vb = list_first_entry(&q->done_list, struct vb2_buffer,
+ done_entry);
+ spin_unlock_irqrestore(&q->done_lock, flags);
+
+ if (!vb)
+ goto end;
+
+ if (vb->state == VB2_BUF_STATE_DONE
+ || vb->state == VB2_BUF_STATE_ERROR) {
+ if (V4L2_TYPE_IS_OUTPUT(q->type))
+ ret = POLLOUT | POLLWRNORM;
+ else
+ ret = POLLIN | POLLRDNORM;
+ }
+end:
+ mutex_unlock(&q->vb_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vb2_poll);
+
+/**
+ * vb2_queue_init() - initialize a videobuf2 queue
+ * @q: videobuf2 queue; this structure should be allocated in driver
+ * @ops: driver-specific callbacks
+ * @alloc_ctx: memory handler/allocator-specific context to be used;
+ * the given context will be used for memory allocation on all
+ * planes and buffers; it is possible to assign different contexts
+ * per plane, use vb2_set_alloc_ctx() for that
+ * @type: queue type
+ * @drv_priv: driver private data, may be NULL; it can be used by driver in
+ * driver-specific callbacks when issued
+ */
+int vb2_queue_init(struct vb2_queue *q, const struct vb2_ops *ops,
+ const struct vb2_alloc_ctx *alloc_ctx,
+ enum v4l2_buf_type type, void *drv_priv)
+{
+ unsigned int i;
+
+ BUG_ON(!q);
+ BUG_ON(!ops);
+ BUG_ON(!ops->queue_negotiate);
+ BUG_ON(!ops->plane_setup);
+ BUG_ON(!ops->buf_queue);
+
+ BUG_ON(!alloc_ctx);
+ BUG_ON(!alloc_ctx->mem_ops);
+
+ memset(q, 0, sizeof *q);
+ q->ops = ops;
+
+ for (i = 0; i < VIDEO_MAX_PLANES; ++i)
+ q->alloc_ctx[i] = alloc_ctx;
+
+ q->type = type;
+ q->drv_priv = drv_priv;
+
+ mutex_init(&q->vb_lock);
+ INIT_LIST_HEAD(&q->queued_list);
+ INIT_LIST_HEAD(&q->done_list);
+ spin_lock_init(&q->done_lock);
+ init_waitqueue_head(&q->done_wq);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(vb2_queue_init);
+
+/**
+ * vb2_queue_release() - stop streaming, release the queue and free memory
+ * @q: videobuf2 queue
+ *
+ * This function stops streaming and performs necessary clean ups, including
+ * freeing video buffer memory. The driver is responsible for freeing
+ * the vb2_queue structure itself.
+ */
+void vb2_queue_release(struct vb2_queue *q)
+{
+ mutex_lock(&q->vb_lock);
+
+ __vb2_queue_cancel(q);
+ __vb2_queue_free(q);
+
+ mutex_unlock(&q->vb_lock);
+}
+EXPORT_SYMBOL_GPL(vb2_queue_release);
+
+MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2");
+MODULE_AUTHOR("Pawel Osciak");
+MODULE_LICENSE("GPL");
new file mode 100644
@@ -0,0 +1,371 @@
+/*
+ * videobuf2-core.h - V4L2 driver helper framework
+ *
+ * Copyright (C) 2010 Samsung Electronics
+ *
+ * Author: Pawel Osciak <p.osciak@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ */
+#ifndef _MEDIA_VIDEOBUF2_CORE_H
+#define _MEDIA_VIDEOBUF2_CORE_H
+
+#include <linux/mutex.h>
+#include <linux/mm_types.h>
+#include <linux/videodev2.h>
+#include <linux/poll.h>
+
+struct vb2_alloc_ctx;
+
+/**
+ * struct vb2_mem_ops - memory handling/memory allocator operations
+ * @alloc: allocate video memory and, optionally, allocator private data,
+ * return NULL on failure or a pointer to allocator private,
+ * per-buffer data on success, NULL on failure; the returned
+ * private structure will then be passed as buf_priv argument
+ * to other ops in this structure
+ * @put: inform the allocator that the buffer will no longer be used;
+ * 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
+ * @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
+ * @put_userptr: inform the allocator that a USERPTR buffer will no longer
+ * be used
+ * @vaddr: return a kernel virtual address to a given memory buffer
+ * associated with the passed private structure or NULL if no
+ * such mapping exists
+ * @paddr: return a physical address to a given memory buffer associated
+ * with the passed private structure or NULL if not 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
+ * @mmap: setup a userspace mapping for a given memory buffer under
+ * the provided virtual memory region
+ *
+ * Required ops for USERPTR types: get_userptr, put_userptr.
+ * Required ops for MMAP types: alloc, put, num_users, mmap.
+ */
+struct vb2_mem_ops {
+ void *(*alloc)(const struct vb2_alloc_ctx *alloc_ctx,
+ unsigned long size);
+ void (*put)(void *buf_priv);
+
+ void *(*get_userptr)(unsigned long vaddr,
+ unsigned long size);
+ void (*put_userptr)(void *buf_priv);
+
+ void *(*vaddr)(void *buf_priv);
+ unsigned long (*paddr)(void *buf_priv);
+ unsigned int (*num_users)(void *buf_priv);
+
+ int (*mmap)(void *buf_priv, struct vm_area_struct *vma);
+};
+
+/**
+ * struct vb2_alloc_ctx - allocator/memory handler-specific context
+ * @mem_ops: memory operations used by the current context
+ *
+ * This structure is passed to the alloc() call and can be used to store
+ * additional allocator private data. In such case it can be embedded in
+ * a allocator private structure as its first member.
+ * In more complicated cases, separate contexts can be assigned to each plane,
+ * if required. This would allow separate memory allocation/handling strategies
+ * for each plane, which is useful for drivers requiring different memory types
+ * and/or handling for each plane.
+ *
+ * See videobuf2-vmalloc.c and videobuf2-dma-coherent.c for example usage.
+ */
+struct vb2_alloc_ctx {
+ const struct vb2_mem_ops *mem_ops;
+};
+
+struct vb2_plane {
+ void *mem_priv;
+ int mapped:1;
+};
+
+/**
+ * enum vb2_buffer_state - current video buffer state
+ * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control
+ * @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in driver
+ * @VB2_BUF_STATE_ACTIVE: buffer queued in driver and possibly used
+ * in a hardware operation
+ * @VB2_BUF_STATE_DONE: buffer returned from driver to videobuf, but
+ * not yet dequeued to userspace
+ * @VB2_BUF_STATE_ERROR: same as above, but the operation on the buffer
+ * has ended with an error, which will be reported
+ * to the userspace when it is dequeued
+ */
+enum vb2_buffer_state {
+ VB2_BUF_STATE_DEQUEUED,
+ VB2_BUF_STATE_QUEUED,
+ VB2_BUF_STATE_ACTIVE,
+ VB2_BUF_STATE_DONE,
+ VB2_BUF_STATE_ERROR,
+};
+
+struct vb2_queue;
+
+/**
+ * struct vb2_buffer - represents a video buffer
+ * @v4l2_buf: struct v4l2_buffer associated with this buffer; can
+ * be read by the driver and relevant entries can be
+ * changed by the driver in case of CAPTURE types
+ * (such as timestamp)
+ * @v4l2_planes: struct v4l2_planes associated with this buffer; can
+ * be read by the driver and relevant entries can be
+ * changed by the driver in case of CAPTURE types
+ * (such as bytesused); NOTE that even for single-planar
+ * types, the v4l2_planes[0] struct should be used
+ * instead of v4l2_buf for filling bytesused - drivers
+ * should use the vb2_set_plane_payload() function for that
+ * @vb2_queue: the queue to which this driver belongs
+ * @drv_entry: list entry to be used by driver for storing the buffer
+ * @num_planes: number of planes in the buffer
+ * on an internal driver queue
+ * @state: current buffer state; do not change
+ * @queued_entry: entry on the queued buffers list, which holds all
+ * buffers queued from userspace
+ * @done_entry: entry on the list that stores all buffers ready to
+ * be dequeued to userspace
+ * @planes: private per-plane information; do not change
+ * @num_planes_mapped: number of mapped planes; do not change
+ */
+struct vb2_buffer {
+ struct v4l2_buffer v4l2_buf;
+ struct v4l2_plane v4l2_planes[VIDEO_MAX_PLANES];
+
+ struct vb2_queue *vb2_queue;
+
+ unsigned int num_planes;
+
+/* Private: internal use only */
+ enum vb2_buffer_state state;
+
+ struct list_head queued_entry;
+ struct list_head done_entry;
+
+ struct vb2_plane planes[VIDEO_MAX_PLANES];
+ unsigned int num_planes_mapped;
+};
+
+/**
+ * struct vb2_ops - driver-specific callbacks
+ *
+ * @queue_negotiate: called from a VIDIOC_REQBUFS handler, before
+ * memory allocation; driver should return the required
+ * number of buffers in num_buffers and the required number
+ * of planes per buffer in num_planes
+ * @plane_setup: called before memory allocation num_planes times;
+ * driver should return the required size of plane number
+ * plane_no
+ * @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
+ * @buf_prepare: called every time the buffer is queued from userspace;
+ * drivers may perform any initialization required before
+ * each hardware operation in this callback;
+ * if an error is returned, the buffer will not be queued
+ * 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
+ * @buf_cleanup: called once before the buffer is freed; drivers may
+ * perform any additional cleanup; optional
+ * @start_streaming: called once before entering 'streaming' state; enables
+ * driver to recieve buffers over buf_queue() callback
+ * @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()
+ * callback
+ * @buf_queue: passes buffer vb to the driver; driver may start
+ * hardware operation on this buffer; driver should give
+ * the buffer back by calling vb2_buffer_done() function
+ */
+struct vb2_ops {
+ int (*queue_negotiate)(struct vb2_queue *q, unsigned int *num_buffers,
+ unsigned int *num_planes);
+ int (*plane_setup)(struct vb2_queue *q,
+ unsigned int plane_no, unsigned long *plane_size);
+
+ int (*buf_init)(struct vb2_buffer *vb);
+ int (*buf_prepare)(struct vb2_buffer *vb);
+ int (*buf_finish)(struct vb2_buffer *vb);
+ void (*buf_cleanup)(struct vb2_buffer *vb);
+
+ int (*start_streaming)(struct vb2_queue *q);
+ int (*stop_streaming)(struct vb2_queue *q);
+ void (*buf_queue)(struct vb2_buffer *vb);
+};
+
+/**
+ * struct vb2_queue - a videobuf queue
+ *
+ * @type: current queue type
+ * @memory: current memory type used
+ * @drv_priv: driver private data, passed on vb2_queue_init
+ * @bufs: videobuf buffer structures
+ * @num_buffers: number of allocated/used buffers
+ * @vb_lock: for ioctl handler and queue state changes synchronization
+ * @queued_list: list of buffers currently queued from userspace
+ * @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
+ * @ops: driver-specific callbacks
+ * @alloc_ctx: memory type/allocator-specific callbacks
+ * @streaming: current streaming state
+ * @userptr_supported: true if queue supports USERPTR types
+ * @mmap_supported: true if queue supports MMAP types
+ */
+struct vb2_queue {
+ enum v4l2_buf_type type;
+ enum v4l2_memory memory;
+ void *drv_priv;
+
+/* private: internal use only */
+ struct vb2_buffer *bufs[VIDEO_MAX_FRAME];
+ unsigned int num_buffers;
+
+ struct mutex vb_lock;
+ struct list_head queued_list;
+
+ struct list_head done_list;
+ spinlock_t done_lock;
+ wait_queue_head_t done_wq;
+
+ const struct vb2_ops *ops;
+ const struct vb2_alloc_ctx *alloc_ctx[VIDEO_MAX_PLANES];
+
+ int streaming:1;
+ int userptr_supported:1;
+ int mmap_supported:1;
+};
+
+void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no);
+unsigned long vb2_plane_paddr(struct vb2_buffer *vb, unsigned int plane_no);
+void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state);
+bool vb2_has_consumers(struct vb2_queue *q);
+
+int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b);
+int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req);
+
+int vb2_queue_init(struct vb2_queue *q, const struct vb2_ops *ops,
+ const struct vb2_alloc_ctx *alloc_ctx,
+ enum v4l2_buf_type type, void *drv_priv);
+void vb2_queue_release(struct vb2_queue *q);
+
+int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b);
+int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking);
+
+int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type);
+int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type);
+
+int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma);
+unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait);
+
+/**
+ * vb2_is_streaming() - return streaming status of the queue
+ * @q: videobuf queue
+ */
+static inline bool vb2_is_streaming(struct vb2_queue *q)
+{
+ return q->streaming;
+}
+
+/**
+ * vb2_lock() - lock the queue
+ * @q: videobuf queue
+ *
+ * This function can be used to obtain internal vb2 lock and block any
+ * concurrent calls to vb2. Usefull for implementing S_FMT and similar
+ * operations that requires exclusive access to driver and it's queue.
+ */
+static inline void vb2_lock(struct vb2_queue *q)
+{
+ mutex_lock(&q->vb_lock);
+}
+
+/**
+ * vb2_unlock() - unlock the queue
+ * @q: videobuf queue
+ *
+ * This function can be used to release internal vb2 lock and let it
+ * any pending calls to vb2.
+ */
+static inline void vb2_unlock(struct vb2_queue *q)
+{
+ mutex_unlock(&q->vb_lock);
+}
+
+/**
+ * vb2_get_drv_priv() - return driver private data associated with the queue
+ * @q: videobuf queue
+ */
+static inline void *vb2_get_drv_priv(struct vb2_queue *q)
+{
+ return q->drv_priv;
+}
+
+/**
+ * vb2_set_plane_payload() - set bytesused for the plane plane_no
+ * @vb: buffer for which plane payload should be set
+ * @plane_no: plane number for which payload should be set
+ * @size: payload in bytes
+ */
+static inline void vb2_set_plane_payload(struct vb2_buffer *vb,
+ unsigned int plane_no, unsigned long size)
+{
+ if (!V4L2_TYPE_IS_MULTIPLANAR(vb->vb2_queue->type) && plane_no == 0)
+ vb->v4l2_buf.bytesused = size;
+ else
+ vb->v4l2_planes[plane_no].bytesused = size;
+}
+
+/**
+ * vb2_plane_size() - return plane size in bytes
+ * @vb: buffer for which plane size should be returned
+ * @plane_no: plane number for which size should be returned
+ */
+static inline unsigned long
+vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no)
+{
+ if (plane_no < vb->num_planes)
+ return vb->v4l2_planes[plane_no].length;
+ else
+ return 0;
+}
+
+/**
+ * vb2_set_alloc_ctx() - use to assign a allocator context for a plane
+ * @q: videobuf queue
+ * @alloc_ctx: allocator context to be assigned
+ * @plane_no: plane number to which the context is to be assigned
+ *
+ * This function can be used to assign additional allocator contexts
+ * on a per-plane basis, if a driver requires such feature.
+ * When a driver passes an allocator context to the vb2_queue_init call,
+ * it is initially assigned to all planes. Driver can then use this call
+ * to selectively assign additional contexts to particular planes.
+ * A context assigned to plane_no will be used for memory operations
+ * on plane number plane_no for all buffers.
+ */
+static inline void
+vb2_set_alloc_ctx(struct vb2_queue *q, struct vb2_alloc_ctx *alloc_ctx,
+ unsigned int plane_no)
+{
+ if (plane_no < VIDEO_MAX_PLANES)
+ q->alloc_ctx[plane_no] = alloc_ctx;
+}
+
+#endif /* _MEDIA_VIDEOBUF2_CORE_H */