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Diffstat (limited to 'drivers/media/platform/omap3isp/ispqueue.c')
-rw-r--r--drivers/media/platform/omap3isp/ispqueue.c1161
1 files changed, 0 insertions, 1161 deletions
diff --git a/drivers/media/platform/omap3isp/ispqueue.c b/drivers/media/platform/omap3isp/ispqueue.c
deleted file mode 100644
index a5e65858e79..00000000000
--- a/drivers/media/platform/omap3isp/ispqueue.c
+++ /dev/null
@@ -1,1161 +0,0 @@
-/*
- * ispqueue.c
- *
- * TI OMAP3 ISP - Video buffers queue handling
- *
- * Copyright (C) 2010 Nokia Corporation
- *
- * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
- * Sakari Ailus <sakari.ailus@iki.fi>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
- * 02110-1301 USA
- */
-
-#include <asm/cacheflush.h>
-#include <linux/dma-mapping.h>
-#include <linux/mm.h>
-#include <linux/pagemap.h>
-#include <linux/poll.h>
-#include <linux/scatterlist.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-
-#include "ispqueue.h"
-
-/* -----------------------------------------------------------------------------
- * Video buffers management
- */
-
-/*
- * isp_video_buffer_cache_sync - Keep the buffers coherent between CPU and ISP
- *
- * The typical operation required here is Cache Invalidation across
- * the (user space) buffer address range. And this _must_ be done
- * at QBUF stage (and *only* at QBUF).
- *
- * We try to use optimal cache invalidation function:
- * - dmac_map_area:
- * - used when the number of pages are _low_.
- * - it becomes quite slow as the number of pages increase.
- * - for 648x492 viewfinder (150 pages) it takes 1.3 ms.
- * - for 5 Mpix buffer (2491 pages) it takes between 25-50 ms.
- *
- * - flush_cache_all:
- * - used when the number of pages are _high_.
- * - time taken in the range of 500-900 us.
- * - has a higher penalty but, as whole dcache + icache is invalidated
- */
-/*
- * FIXME: dmac_inv_range crashes randomly on the user space buffer
- * address. Fall back to flush_cache_all for now.
- */
-#define ISP_CACHE_FLUSH_PAGES_MAX 0
-
-static void isp_video_buffer_cache_sync(struct isp_video_buffer *buf)
-{
- if (buf->skip_cache)
- return;
-
- if (buf->vbuf.m.userptr == 0 || buf->npages == 0 ||
- buf->npages > ISP_CACHE_FLUSH_PAGES_MAX)
- flush_cache_all();
- else {
- dmac_map_area((void *)buf->vbuf.m.userptr, buf->vbuf.length,
- DMA_FROM_DEVICE);
- outer_inv_range(buf->vbuf.m.userptr,
- buf->vbuf.m.userptr + buf->vbuf.length);
- }
-}
-
-/*
- * isp_video_buffer_lock_vma - Prevent VMAs from being unmapped
- *
- * Lock the VMAs underlying the given buffer into memory. This avoids the
- * userspace buffer mapping from being swapped out, making VIPT cache handling
- * easier.
- *
- * Note that the pages will not be freed as the buffers have been locked to
- * memory using by a call to get_user_pages(), but the userspace mapping could
- * still disappear if the VMAs are not locked. This is caused by the memory
- * management code trying to be as lock-less as possible, which results in the
- * userspace mapping manager not finding out that the pages are locked under
- * some conditions.
- */
-static int isp_video_buffer_lock_vma(struct isp_video_buffer *buf, int lock)
-{
- struct vm_area_struct *vma;
- unsigned long start;
- unsigned long end;
- int ret = 0;
-
- if (buf->vbuf.memory == V4L2_MEMORY_MMAP)
- return 0;
-
- /* We can be called from workqueue context if the current task dies to
- * unlock the VMAs. In that case there's no current memory management
- * context so unlocking can't be performed, but the VMAs have been or
- * are getting destroyed anyway so it doesn't really matter.
- */
- if (!current || !current->mm)
- return lock ? -EINVAL : 0;
-
- start = buf->vbuf.m.userptr;
- end = buf->vbuf.m.userptr + buf->vbuf.length - 1;
-
- down_write(&current->mm->mmap_sem);
- spin_lock(&current->mm->page_table_lock);
-
- do {
- vma = find_vma(current->mm, start);
- if (vma == NULL) {
- ret = -EFAULT;
- goto out;
- }
-
- if (lock)
- vma->vm_flags |= VM_LOCKED;
- else
- vma->vm_flags &= ~VM_LOCKED;
-
- start = vma->vm_end + 1;
- } while (vma->vm_end < end);
-
- if (lock)
- buf->vm_flags |= VM_LOCKED;
- else
- buf->vm_flags &= ~VM_LOCKED;
-
-out:
- spin_unlock(&current->mm->page_table_lock);
- up_write(&current->mm->mmap_sem);
- return ret;
-}
-
-/*
- * isp_video_buffer_sglist_kernel - Build a scatter list for a vmalloc'ed buffer
- *
- * Iterate over the vmalloc'ed area and create a scatter list entry for every
- * page.
- */
-static int isp_video_buffer_sglist_kernel(struct isp_video_buffer *buf)
-{
- struct scatterlist *sglist;
- unsigned int npages;
- unsigned int i;
- void *addr;
-
- addr = buf->vaddr;
- npages = PAGE_ALIGN(buf->vbuf.length) >> PAGE_SHIFT;
-
- sglist = vmalloc(npages * sizeof(*sglist));
- if (sglist == NULL)
- return -ENOMEM;
-
- sg_init_table(sglist, npages);
-
- for (i = 0; i < npages; ++i, addr += PAGE_SIZE) {
- struct page *page = vmalloc_to_page(addr);
-
- if (page == NULL || PageHighMem(page)) {
- vfree(sglist);
- return -EINVAL;
- }
-
- sg_set_page(&sglist[i], page, PAGE_SIZE, 0);
- }
-
- buf->sglen = npages;
- buf->sglist = sglist;
-
- return 0;
-}
-
-/*
- * isp_video_buffer_sglist_user - Build a scatter list for a userspace buffer
- *
- * Walk the buffer pages list and create a 1:1 mapping to a scatter list.
- */
-static int isp_video_buffer_sglist_user(struct isp_video_buffer *buf)
-{
- struct scatterlist *sglist;
- unsigned int offset = buf->offset;
- unsigned int i;
-
- sglist = vmalloc(buf->npages * sizeof(*sglist));
- if (sglist == NULL)
- return -ENOMEM;
-
- sg_init_table(sglist, buf->npages);
-
- for (i = 0; i < buf->npages; ++i) {
- if (PageHighMem(buf->pages[i])) {
- vfree(sglist);
- return -EINVAL;
- }
-
- sg_set_page(&sglist[i], buf->pages[i], PAGE_SIZE - offset,
- offset);
- offset = 0;
- }
-
- buf->sglen = buf->npages;
- buf->sglist = sglist;
-
- return 0;
-}
-
-/*
- * isp_video_buffer_sglist_pfnmap - Build a scatter list for a VM_PFNMAP buffer
- *
- * Create a scatter list of physically contiguous pages starting at the buffer
- * memory physical address.
- */
-static int isp_video_buffer_sglist_pfnmap(struct isp_video_buffer *buf)
-{
- struct scatterlist *sglist;
- unsigned int offset = buf->offset;
- unsigned long pfn = buf->paddr >> PAGE_SHIFT;
- unsigned int i;
-
- sglist = vmalloc(buf->npages * sizeof(*sglist));
- if (sglist == NULL)
- return -ENOMEM;
-
- sg_init_table(sglist, buf->npages);
-
- for (i = 0; i < buf->npages; ++i, ++pfn) {
- sg_set_page(&sglist[i], pfn_to_page(pfn), PAGE_SIZE - offset,
- offset);
- /* PFNMAP buffers will not get DMA-mapped, set the DMA address
- * manually.
- */
- sg_dma_address(&sglist[i]) = (pfn << PAGE_SHIFT) + offset;
- offset = 0;
- }
-
- buf->sglen = buf->npages;
- buf->sglist = sglist;
-
- return 0;
-}
-
-/*
- * isp_video_buffer_cleanup - Release pages for a userspace VMA.
- *
- * Release pages locked by a call isp_video_buffer_prepare_user and free the
- * pages table.
- */
-static void isp_video_buffer_cleanup(struct isp_video_buffer *buf)
-{
- enum dma_data_direction direction;
- unsigned int i;
-
- if (buf->queue->ops->buffer_cleanup)
- buf->queue->ops->buffer_cleanup(buf);
-
- if (!(buf->vm_flags & VM_PFNMAP)) {
- direction = buf->vbuf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE
- ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
- dma_unmap_sg(buf->queue->dev, buf->sglist, buf->sglen,
- direction);
- }
-
- vfree(buf->sglist);
- buf->sglist = NULL;
- buf->sglen = 0;
-
- if (buf->pages != NULL) {
- isp_video_buffer_lock_vma(buf, 0);
-
- for (i = 0; i < buf->npages; ++i)
- page_cache_release(buf->pages[i]);
-
- vfree(buf->pages);
- buf->pages = NULL;
- }
-
- buf->npages = 0;
- buf->skip_cache = false;
-}
-
-/*
- * isp_video_buffer_prepare_user - Pin userspace VMA pages to memory.
- *
- * This function creates a list of pages for a userspace VMA. The number of
- * pages is first computed based on the buffer size, and pages are then
- * retrieved by a call to get_user_pages.
- *
- * Pages are pinned to memory by get_user_pages, making them available for DMA
- * transfers. However, due to memory management optimization, it seems the
- * get_user_pages doesn't guarantee that the pinned pages will not be written
- * to swap and removed from the userspace mapping(s). When this happens, a page
- * fault can be generated when accessing those unmapped pages.
- *
- * If the fault is triggered by a page table walk caused by VIPT cache
- * management operations, the page fault handler might oops if the MM semaphore
- * is held, as it can't handle kernel page faults in that case. To fix that, a
- * fixup entry needs to be added to the cache management code, or the userspace
- * VMA must be locked to avoid removing pages from the userspace mapping in the
- * first place.
- *
- * If the number of pages retrieved is smaller than the number required by the
- * buffer size, the function returns -EFAULT.
- */
-static int isp_video_buffer_prepare_user(struct isp_video_buffer *buf)
-{
- unsigned long data;
- unsigned int first;
- unsigned int last;
- int ret;
-
- data = buf->vbuf.m.userptr;
- first = (data & PAGE_MASK) >> PAGE_SHIFT;
- last = ((data + buf->vbuf.length - 1) & PAGE_MASK) >> PAGE_SHIFT;
-
- buf->offset = data & ~PAGE_MASK;
- buf->npages = last - first + 1;
- buf->pages = vmalloc(buf->npages * sizeof(buf->pages[0]));
- if (buf->pages == NULL)
- return -ENOMEM;
-
- down_read(&current->mm->mmap_sem);
- ret = get_user_pages(current, current->mm, data & PAGE_MASK,
- buf->npages,
- buf->vbuf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE, 0,
- buf->pages, NULL);
- up_read(&current->mm->mmap_sem);
-
- if (ret != buf->npages) {
- buf->npages = ret < 0 ? 0 : ret;
- isp_video_buffer_cleanup(buf);
- return -EFAULT;
- }
-
- ret = isp_video_buffer_lock_vma(buf, 1);
- if (ret < 0)
- isp_video_buffer_cleanup(buf);
-
- return ret;
-}
-
-/*
- * isp_video_buffer_prepare_pfnmap - Validate a VM_PFNMAP userspace buffer
- *
- * Userspace VM_PFNMAP buffers are supported only if they are contiguous in
- * memory and if they span a single VMA.
- *
- * Return 0 if the buffer is valid, or -EFAULT otherwise.
- */
-static int isp_video_buffer_prepare_pfnmap(struct isp_video_buffer *buf)
-{
- struct vm_area_struct *vma;
- unsigned long prev_pfn;
- unsigned long this_pfn;
- unsigned long start;
- unsigned long end;
- dma_addr_t pa = 0;
- int ret = -EFAULT;
-
- start = buf->vbuf.m.userptr;
- end = buf->vbuf.m.userptr + buf->vbuf.length - 1;
-
- buf->offset = start & ~PAGE_MASK;
- buf->npages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1;
- buf->pages = NULL;
-
- down_read(&current->mm->mmap_sem);
- vma = find_vma(current->mm, start);
- if (vma == NULL || vma->vm_end < end)
- goto done;
-
- for (prev_pfn = 0; start <= end; start += PAGE_SIZE) {
- ret = follow_pfn(vma, start, &this_pfn);
- if (ret)
- goto done;
-
- if (prev_pfn == 0)
- pa = this_pfn << PAGE_SHIFT;
- else if (this_pfn != prev_pfn + 1) {
- ret = -EFAULT;
- goto done;
- }
-
- prev_pfn = this_pfn;
- }
-
- buf->paddr = pa + buf->offset;
- ret = 0;
-
-done:
- up_read(&current->mm->mmap_sem);
- return ret;
-}
-
-/*
- * isp_video_buffer_prepare_vm_flags - Get VMA flags for a userspace address
- *
- * This function locates the VMAs for the buffer's userspace address and checks
- * that their flags match. The only flag that we need to care for at the moment
- * is VM_PFNMAP.
- *
- * The buffer vm_flags field is set to the first VMA flags.
- *
- * Return -EFAULT if no VMA can be found for part of the buffer, or if the VMAs
- * have incompatible flags.
- */
-static int isp_video_buffer_prepare_vm_flags(struct isp_video_buffer *buf)
-{
- struct vm_area_struct *vma;
- pgprot_t uninitialized_var(vm_page_prot);
- unsigned long start;
- unsigned long end;
- int ret = -EFAULT;
-
- start = buf->vbuf.m.userptr;
- end = buf->vbuf.m.userptr + buf->vbuf.length - 1;
-
- down_read(&current->mm->mmap_sem);
-
- do {
- vma = find_vma(current->mm, start);
- if (vma == NULL)
- goto done;
-
- if (start == buf->vbuf.m.userptr) {
- buf->vm_flags = vma->vm_flags;
- vm_page_prot = vma->vm_page_prot;
- }
-
- if ((buf->vm_flags ^ vma->vm_flags) & VM_PFNMAP)
- goto done;
-
- if (vm_page_prot != vma->vm_page_prot)
- goto done;
-
- start = vma->vm_end + 1;
- } while (vma->vm_end < end);
-
- /* Skip cache management to enhance performances for non-cached or
- * write-combining buffers.
- */
- if (vm_page_prot == pgprot_noncached(vm_page_prot) ||
- vm_page_prot == pgprot_writecombine(vm_page_prot))
- buf->skip_cache = true;
-
- ret = 0;
-
-done:
- up_read(&current->mm->mmap_sem);
- return ret;
-}
-
-/*
- * isp_video_buffer_prepare - Make a buffer ready for operation
- *
- * Preparing a buffer involves:
- *
- * - validating VMAs (userspace buffers only)
- * - locking pages and VMAs into memory (userspace buffers only)
- * - building page and scatter-gather lists
- * - mapping buffers for DMA operation
- * - performing driver-specific preparation
- *
- * The function must be called in userspace context with a valid mm context
- * (this excludes cleanup paths such as sys_close when the userspace process
- * segfaults).
- */
-static int isp_video_buffer_prepare(struct isp_video_buffer *buf)
-{
- enum dma_data_direction direction;
- int ret;
-
- switch (buf->vbuf.memory) {
- case V4L2_MEMORY_MMAP:
- ret = isp_video_buffer_sglist_kernel(buf);
- break;
-
- case V4L2_MEMORY_USERPTR:
- ret = isp_video_buffer_prepare_vm_flags(buf);
- if (ret < 0)
- return ret;
-
- if (buf->vm_flags & VM_PFNMAP) {
- ret = isp_video_buffer_prepare_pfnmap(buf);
- if (ret < 0)
- return ret;
-
- ret = isp_video_buffer_sglist_pfnmap(buf);
- } else {
- ret = isp_video_buffer_prepare_user(buf);
- if (ret < 0)
- return ret;
-
- ret = isp_video_buffer_sglist_user(buf);
- }
- break;
-
- default:
- return -EINVAL;
- }
-
- if (ret < 0)
- goto done;
-
- if (!(buf->vm_flags & VM_PFNMAP)) {
- direction = buf->vbuf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE
- ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
- ret = dma_map_sg(buf->queue->dev, buf->sglist, buf->sglen,
- direction);
- if (ret != buf->sglen) {
- ret = -EFAULT;
- goto done;
- }
- }
-
- if (buf->queue->ops->buffer_prepare)
- ret = buf->queue->ops->buffer_prepare(buf);
-
-done:
- if (ret < 0) {
- isp_video_buffer_cleanup(buf);
- return ret;
- }
-
- return ret;
-}
-
-/*
- * isp_video_queue_query - Query the status of a given buffer
- *
- * Locking: must be called with the queue lock held.
- */
-static void isp_video_buffer_query(struct isp_video_buffer *buf,
- struct v4l2_buffer *vbuf)
-{
- memcpy(vbuf, &buf->vbuf, sizeof(*vbuf));
-
- if (buf->vma_use_count)
- vbuf->flags |= V4L2_BUF_FLAG_MAPPED;
-
- switch (buf->state) {
- case ISP_BUF_STATE_ERROR:
- vbuf->flags |= V4L2_BUF_FLAG_ERROR;
- /* Fallthrough */
- case ISP_BUF_STATE_DONE:
- vbuf->flags |= V4L2_BUF_FLAG_DONE;
- break;
- case ISP_BUF_STATE_QUEUED:
- case ISP_BUF_STATE_ACTIVE:
- vbuf->flags |= V4L2_BUF_FLAG_QUEUED;
- break;
- case ISP_BUF_STATE_IDLE:
- default:
- break;
- }
-}
-
-/*
- * isp_video_buffer_wait - Wait for a buffer to be ready
- *
- * In non-blocking mode, return immediately with 0 if the buffer is ready or
- * -EAGAIN if the buffer is in the QUEUED or ACTIVE state.
- *
- * In blocking mode, wait (interruptibly but with no timeout) on the buffer wait
- * queue using the same condition.
- */
-static int isp_video_buffer_wait(struct isp_video_buffer *buf, int nonblocking)
-{
- if (nonblocking) {
- return (buf->state != ISP_BUF_STATE_QUEUED &&
- buf->state != ISP_BUF_STATE_ACTIVE)
- ? 0 : -EAGAIN;
- }
-
- return wait_event_interruptible(buf->wait,
- buf->state != ISP_BUF_STATE_QUEUED &&
- buf->state != ISP_BUF_STATE_ACTIVE);
-}
-
-/* -----------------------------------------------------------------------------
- * Queue management
- */
-
-/*
- * isp_video_queue_free - Free video buffers memory
- *
- * Buffers can only be freed if the queue isn't streaming and if no buffer is
- * mapped to userspace. Return -EBUSY if those conditions aren't satisfied.
- *
- * This function must be called with the queue lock held.
- */
-static int isp_video_queue_free(struct isp_video_queue *queue)
-{
- unsigned int i;
-
- if (queue->streaming)
- return -EBUSY;
-
- for (i = 0; i < queue->count; ++i) {
- if (queue->buffers[i]->vma_use_count != 0)
- return -EBUSY;
- }
-
- for (i = 0; i < queue->count; ++i) {
- struct isp_video_buffer *buf = queue->buffers[i];
-
- isp_video_buffer_cleanup(buf);
-
- vfree(buf->vaddr);
- buf->vaddr = NULL;
-
- kfree(buf);
- queue->buffers[i] = NULL;
- }
-
- INIT_LIST_HEAD(&queue->queue);
- queue->count = 0;
- return 0;
-}
-
-/*
- * isp_video_queue_alloc - Allocate video buffers memory
- *
- * This function must be called with the queue lock held.
- */
-static int isp_video_queue_alloc(struct isp_video_queue *queue,
- unsigned int nbuffers,
- unsigned int size, enum v4l2_memory memory)
-{
- struct isp_video_buffer *buf;
- unsigned int i;
- void *mem;
- int ret;
-
- /* Start by freeing the buffers. */
- ret = isp_video_queue_free(queue);
- if (ret < 0)
- return ret;
-
- /* Bail out if no buffers should be allocated. */
- if (nbuffers == 0)
- return 0;
-
- /* Initialize the allocated buffers. */
- for (i = 0; i < nbuffers; ++i) {
- buf = kzalloc(queue->bufsize, GFP_KERNEL);
- if (buf == NULL)
- break;
-
- if (memory == V4L2_MEMORY_MMAP) {
- /* Allocate video buffers memory for mmap mode. Align
- * the size to the page size.
- */
- mem = vmalloc_32_user(PAGE_ALIGN(size));
- if (mem == NULL) {
- kfree(buf);
- break;
- }
-
- buf->vbuf.m.offset = i * PAGE_ALIGN(size);
- buf->vaddr = mem;
- }
-
- buf->vbuf.index = i;
- buf->vbuf.length = size;
- buf->vbuf.type = queue->type;
- buf->vbuf.flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
- buf->vbuf.field = V4L2_FIELD_NONE;
- buf->vbuf.memory = memory;
-
- buf->queue = queue;
- init_waitqueue_head(&buf->wait);
-
- queue->buffers[i] = buf;
- }
-
- if (i == 0)
- return -ENOMEM;
-
- queue->count = i;
- return nbuffers;
-}
-
-/**
- * omap3isp_video_queue_cleanup - Clean up the video buffers queue
- * @queue: Video buffers queue
- *
- * Free all allocated resources and clean up the video buffers queue. The queue
- * must not be busy (no ongoing video stream) and buffers must have been
- * unmapped.
- *
- * Return 0 on success or -EBUSY if the queue is busy or buffers haven't been
- * unmapped.
- */
-int omap3isp_video_queue_cleanup(struct isp_video_queue *queue)
-{
- return isp_video_queue_free(queue);
-}
-
-/**
- * omap3isp_video_queue_init - Initialize the video buffers queue
- * @queue: Video buffers queue
- * @type: V4L2 buffer type (capture or output)
- * @ops: Driver-specific queue operations
- * @dev: Device used for DMA operations
- * @bufsize: Size of the driver-specific buffer structure
- *
- * Initialize the video buffers queue with the supplied parameters.
- *
- * The queue type must be one of V4L2_BUF_TYPE_VIDEO_CAPTURE or
- * V4L2_BUF_TYPE_VIDEO_OUTPUT. Other buffer types are not supported yet.
- *
- * Buffer objects will be allocated using the given buffer size to allow room
- * for driver-specific fields. Driver-specific buffer structures must start
- * with a struct isp_video_buffer field. Drivers with no driver-specific buffer
- * structure must pass the size of the isp_video_buffer structure in the bufsize
- * parameter.
- *
- * Return 0 on success.
- */
-int omap3isp_video_queue_init(struct isp_video_queue *queue,
- enum v4l2_buf_type type,
- const struct isp_video_queue_operations *ops,
- struct device *dev, unsigned int bufsize)
-{
- INIT_LIST_HEAD(&queue->queue);
- mutex_init(&queue->lock);
- spin_lock_init(&queue->irqlock);
-
- queue->type = type;
- queue->ops = ops;
- queue->dev = dev;
- queue->bufsize = bufsize;
-
- return 0;
-}
-
-/* -----------------------------------------------------------------------------
- * V4L2 operations
- */
-
-/**
- * omap3isp_video_queue_reqbufs - Allocate video buffers memory
- *
- * This function is intended to be used as a VIDIOC_REQBUFS ioctl handler. It
- * allocated video buffer objects and, for MMAP buffers, buffer memory.
- *
- * If the number of buffers is 0, all buffers are freed and the function returns
- * without performing any allocation.
- *
- * If the number of buffers is not 0, currently allocated buffers (if any) are
- * freed and the requested number of buffers are allocated. Depending on
- * driver-specific requirements and on memory availability, a number of buffer
- * smaller or bigger than requested can be allocated. This isn't considered as
- * an error.
- *
- * Return 0 on success or one of the following error codes:
- *
- * -EINVAL if the buffer type or index are invalid
- * -EBUSY if the queue is busy (streaming or buffers mapped)
- * -ENOMEM if the buffers can't be allocated due to an out-of-memory condition
- */
-int omap3isp_video_queue_reqbufs(struct isp_video_queue *queue,
- struct v4l2_requestbuffers *rb)
-{
- unsigned int nbuffers = rb->count;
- unsigned int size;
- int ret;
-
- if (rb->type != queue->type)
- return -EINVAL;
-
- queue->ops->queue_prepare(queue, &nbuffers, &size);
- if (size == 0)
- return -EINVAL;
-
- nbuffers = min_t(unsigned int, nbuffers, ISP_VIDEO_MAX_BUFFERS);
-
- mutex_lock(&queue->lock);
-
- ret = isp_video_queue_alloc(queue, nbuffers, size, rb->memory);
- if (ret < 0)
- goto done;
-
- rb->count = ret;
- ret = 0;
-
-done:
- mutex_unlock(&queue->lock);
- return ret;
-}
-
-/**
- * omap3isp_video_queue_querybuf - Query the status of a buffer in a queue
- *
- * This function is intended to be used as a VIDIOC_QUERYBUF ioctl handler. It
- * returns the status of a given video buffer.
- *
- * Return 0 on success or -EINVAL if the buffer type or index are invalid.
- */
-int omap3isp_video_queue_querybuf(struct isp_video_queue *queue,
- struct v4l2_buffer *vbuf)
-{
- struct isp_video_buffer *buf;
- int ret = 0;
-
- if (vbuf->type != queue->type)
- return -EINVAL;
-
- mutex_lock(&queue->lock);
-
- if (vbuf->index >= queue->count) {
- ret = -EINVAL;
- goto done;
- }
-
- buf = queue->buffers[vbuf->index];
- isp_video_buffer_query(buf, vbuf);
-
-done:
- mutex_unlock(&queue->lock);
- return ret;
-}
-
-/**
- * omap3isp_video_queue_qbuf - Queue a buffer
- *
- * This function is intended to be used as a VIDIOC_QBUF ioctl handler.
- *
- * The v4l2_buffer structure passed from userspace is first sanity tested. If
- * sane, the buffer is then processed and added to the main queue and, if the
- * queue is streaming, to the IRQ queue.
- *
- * Before being enqueued, USERPTR buffers are checked for address changes. If
- * the buffer has a different userspace address, the old memory area is unlocked
- * and the new memory area is locked.
- */
-int omap3isp_video_queue_qbuf(struct isp_video_queue *queue,
- struct v4l2_buffer *vbuf)
-{
- struct isp_video_buffer *buf;
- unsigned long flags;
- int ret = -EINVAL;
-
- if (vbuf->type != queue->type)
- goto done;
-
- mutex_lock(&queue->lock);
-
- if (vbuf->index >= queue->count)
- goto done;
-
- buf = queue->buffers[vbuf->index];
-
- if (vbuf->memory != buf->vbuf.memory)
- goto done;
-
- if (buf->state != ISP_BUF_STATE_IDLE)
- goto done;
-
- if (vbuf->memory == V4L2_MEMORY_USERPTR &&
- vbuf->length < buf->vbuf.length)
- goto done;
-
- if (vbuf->memory == V4L2_MEMORY_USERPTR &&
- vbuf->m.userptr != buf->vbuf.m.userptr) {
- isp_video_buffer_cleanup(buf);
- buf->vbuf.m.userptr = vbuf->m.userptr;
- buf->prepared = 0;
- }
-
- if (!buf->prepared) {
- ret = isp_video_buffer_prepare(buf);
- if (ret < 0)
- goto done;
- buf->prepared = 1;
- }
-
- isp_video_buffer_cache_sync(buf);
-
- buf->state = ISP_BUF_STATE_QUEUED;
- list_add_tail(&buf->stream, &queue->queue);
-
- if (queue->streaming) {
- spin_lock_irqsave(&queue->irqlock, flags);
- queue->ops->buffer_queue(buf);
- spin_unlock_irqrestore(&queue->irqlock, flags);
- }
-
- ret = 0;
-
-done:
- mutex_unlock(&queue->lock);
- return ret;
-}
-
-/**
- * omap3isp_video_queue_dqbuf - Dequeue a buffer
- *
- * This function is intended to be used as a VIDIOC_DQBUF ioctl handler.
- *
- * Wait until a buffer is ready to be dequeued, remove it from the queue and
- * copy its information to the v4l2_buffer structure.
- *
- * If the nonblocking argument is not zero and no buffer is ready, return
- * -EAGAIN immediately instead of waiting.
- *
- * If no buffer has been enqueued, or if the requested buffer type doesn't match
- * the queue type, return -EINVAL.
- */
-int omap3isp_video_queue_dqbuf(struct isp_video_queue *queue,
- struct v4l2_buffer *vbuf, int nonblocking)
-{
- struct isp_video_buffer *buf;
- int ret;
-
- if (vbuf->type != queue->type)
- return -EINVAL;
-
- mutex_lock(&queue->lock);
-
- if (list_empty(&queue->queue)) {
- ret = -EINVAL;
- goto done;
- }
-
- buf = list_first_entry(&queue->queue, struct isp_video_buffer, stream);
- ret = isp_video_buffer_wait(buf, nonblocking);
- if (ret < 0)
- goto done;
-
- list_del(&buf->stream);
-
- isp_video_buffer_query(buf, vbuf);
- buf->state = ISP_BUF_STATE_IDLE;
- vbuf->flags &= ~V4L2_BUF_FLAG_QUEUED;
-
-done:
- mutex_unlock(&queue->lock);
- return ret;
-}
-
-/**
- * omap3isp_video_queue_streamon - Start streaming
- *
- * This function is intended to be used as a VIDIOC_STREAMON ioctl handler. It
- * starts streaming on the queue and calls the buffer_queue operation for all
- * queued buffers.
- *
- * Return 0 on success.
- */
-int omap3isp_video_queue_streamon(struct isp_video_queue *queue)
-{
- struct isp_video_buffer *buf;
- unsigned long flags;
-
- mutex_lock(&queue->lock);
-
- if (queue->streaming)
- goto done;
-
- queue->streaming = 1;
-
- spin_lock_irqsave(&queue->irqlock, flags);
- list_for_each_entry(buf, &queue->queue, stream)
- queue->ops->buffer_queue(buf);
- spin_unlock_irqrestore(&queue->irqlock, flags);
-
-done:
- mutex_unlock(&queue->lock);
- return 0;
-}
-
-/**
- * omap3isp_video_queue_streamoff - Stop streaming
- *
- * This function is intended to be used as a VIDIOC_STREAMOFF ioctl handler. It
- * stops streaming on the queue and wakes up all the buffers.
- *
- * Drivers must stop the hardware and synchronize with interrupt handlers and/or
- * delayed works before calling this function to make sure no buffer will be
- * touched by the driver and/or hardware.
- */
-void omap3isp_video_queue_streamoff(struct isp_video_queue *queue)
-{
- struct isp_video_buffer *buf;
- unsigned long flags;
- unsigned int i;
-
- mutex_lock(&queue->lock);
-
- if (!queue->streaming)
- goto done;
-
- queue->streaming = 0;
-
- spin_lock_irqsave(&queue->irqlock, flags);
- for (i = 0; i < queue->count; ++i) {
- buf = queue->buffers[i];
-
- if (buf->state == ISP_BUF_STATE_ACTIVE)
- wake_up(&buf->wait);
-
- buf->state = ISP_BUF_STATE_IDLE;
- }
- spin_unlock_irqrestore(&queue->irqlock, flags);
-
- INIT_LIST_HEAD(&queue->queue);
-
-done:
- mutex_unlock(&queue->lock);
-}
-
-/**
- * omap3isp_video_queue_discard_done - Discard all buffers marked as DONE
- *
- * This function is intended to be used with suspend/resume operations. It
- * discards all 'done' buffers as they would be too old to be requested after
- * resume.
- *
- * Drivers must stop the hardware and synchronize with interrupt handlers and/or
- * delayed works before calling this function to make sure no buffer will be
- * touched by the driver and/or hardware.
- */
-void omap3isp_video_queue_discard_done(struct isp_video_queue *queue)
-{
- struct isp_video_buffer *buf;
- unsigned int i;
-
- mutex_lock(&queue->lock);
-
- if (!queue->streaming)
- goto done;
-
- for (i = 0; i < queue->count; ++i) {
- buf = queue->buffers[i];
-
- if (buf->state == ISP_BUF_STATE_DONE)
- buf->state = ISP_BUF_STATE_ERROR;
- }
-
-done:
- mutex_unlock(&queue->lock);
-}
-
-static void isp_video_queue_vm_open(struct vm_area_struct *vma)
-{
- struct isp_video_buffer *buf = vma->vm_private_data;
-
- buf->vma_use_count++;
-}
-
-static void isp_video_queue_vm_close(struct vm_area_struct *vma)
-{
- struct isp_video_buffer *buf = vma->vm_private_data;
-
- buf->vma_use_count--;
-}
-
-static const struct vm_operations_struct isp_video_queue_vm_ops = {
- .open = isp_video_queue_vm_open,
- .close = isp_video_queue_vm_close,
-};
-
-/**
- * omap3isp_video_queue_mmap - Map buffers to userspace
- *
- * This function is intended to be used as an mmap() file operation handler. It
- * maps a buffer to userspace based on the VMA offset.
- *
- * Only buffers of memory type MMAP are supported.
- */
-int omap3isp_video_queue_mmap(struct isp_video_queue *queue,
- struct vm_area_struct *vma)
-{
- struct isp_video_buffer *uninitialized_var(buf);
- unsigned long size;
- unsigned int i;
- int ret = 0;
-
- mutex_lock(&queue->lock);
-
- for (i = 0; i < queue->count; ++i) {
- buf = queue->buffers[i];
- if ((buf->vbuf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff)
- break;
- }
-
- if (i == queue->count) {
- ret = -EINVAL;
- goto done;
- }
-
- size = vma->vm_end - vma->vm_start;
-
- if (buf->vbuf.memory != V4L2_MEMORY_MMAP ||
- size != PAGE_ALIGN(buf->vbuf.length)) {
- ret = -EINVAL;
- goto done;
- }
-
- ret = remap_vmalloc_range(vma, buf->vaddr, 0);
- if (ret < 0)
- goto done;
-
- vma->vm_ops = &isp_video_queue_vm_ops;
- vma->vm_private_data = buf;
- isp_video_queue_vm_open(vma);
-
-done:
- mutex_unlock(&queue->lock);
- return ret;
-}
-
-/**
- * omap3isp_video_queue_poll - Poll video queue state
- *
- * This function is intended to be used as a poll() file operation handler. It
- * polls the state of the video buffer at the front of the queue and returns an
- * events mask.
- *
- * If no buffer is present at the front of the queue, POLLERR is returned.
- */
-unsigned int omap3isp_video_queue_poll(struct isp_video_queue *queue,
- struct file *file, poll_table *wait)
-{
- struct isp_video_buffer *buf;
- unsigned int mask = 0;
-
- mutex_lock(&queue->lock);
- if (list_empty(&queue->queue)) {
- mask |= POLLERR;
- goto done;
- }
- buf = list_first_entry(&queue->queue, struct isp_video_buffer, stream);
-
- poll_wait(file, &buf->wait, wait);
- if (buf->state == ISP_BUF_STATE_DONE ||
- buf->state == ISP_BUF_STATE_ERROR) {
- if (queue->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
- mask |= POLLIN | POLLRDNORM;
- else
- mask |= POLLOUT | POLLWRNORM;
- }
-
-done:
- mutex_unlock(&queue->lock);
- return mask;
-}