diff options
| -rw-r--r-- | drivers/media/video/Kconfig | 5 | ||||
| -rw-r--r-- | drivers/media/video/Makefile | 1 | ||||
| -rw-r--r-- | drivers/media/video/videobuf-dma-contig.c | 417 | ||||
| -rw-r--r-- | include/media/videobuf-dma-contig.h | 32 |
4 files changed, 455 insertions, 0 deletions
diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig index 2103f7b..9a4265e 100644 --- a/drivers/media/video/Kconfig +++ b/drivers/media/video/Kconfig @@ -24,6 +24,11 @@ config VIDEOBUF_VMALLOC select VIDEOBUF_GEN tristate +config VIDEOBUF_DMA_CONTIG + depends on HAS_DMA + select VIDEOBUF_GEN + tristate + config VIDEOBUF_DVB tristate select VIDEOBUF_GEN diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile index d5f6eea..3106eaa 100644 --- a/drivers/media/video/Makefile +++ b/drivers/media/video/Makefile @@ -88,6 +88,7 @@ obj-$(CONFIG_VIDEO_TUNER) += tuner.o obj-$(CONFIG_VIDEOBUF_GEN) += videobuf-core.o obj-$(CONFIG_VIDEOBUF_DMA_SG) += videobuf-dma-sg.o +obj-$(CONFIG_VIDEOBUF_DMA_CONTIG) += videobuf-dma-contig.o obj-$(CONFIG_VIDEOBUF_VMALLOC) += videobuf-vmalloc.o obj-$(CONFIG_VIDEOBUF_DVB) += videobuf-dvb.o obj-$(CONFIG_VIDEO_BTCX) += btcx-risc.o diff --git a/drivers/media/video/videobuf-dma-contig.c b/drivers/media/video/videobuf-dma-contig.c new file mode 100644 index 0000000..2475535 --- /dev/null +++ b/drivers/media/video/videobuf-dma-contig.c @@ -0,0 +1,417 @@ +/* + * helper functions for physically contiguous capture buffers + * + * The functions support hardware lacking scatter gather support + * (i.e. the buffers must be linear in physical memory) + * + * Copyright (c) 2008 Magnus Damm + * + * Based on videobuf-vmalloc.c, + * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org> + * + * 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; either version 2 + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/dma-mapping.h> +#include <media/videobuf-dma-contig.h> + +struct videobuf_dma_contig_memory { + u32 magic; + void *vaddr; + dma_addr_t dma_handle; + unsigned long size; +}; + +#define MAGIC_DC_MEM 0x0733ac61 +#define MAGIC_CHECK(is, should) \ + if (unlikely((is) != (should))) { \ + pr_err("magic mismatch: %x expected %x\n", is, should); \ + BUG(); \ + } + +static void +videobuf_vm_open(struct vm_area_struct *vma) +{ + struct videobuf_mapping *map = vma->vm_private_data; + + dev_dbg(map->q->dev, "vm_open %p [count=%u,vma=%08lx-%08lx]\n", + map, map->count, vma->vm_start, vma->vm_end); + + map->count++; +} + +static void videobuf_vm_close(struct vm_area_struct *vma) +{ + struct videobuf_mapping *map = vma->vm_private_data; + struct videobuf_queue *q = map->q; + int i; + + dev_dbg(map->q->dev, "vm_close %p [count=%u,vma=%08lx-%08lx]\n", + map, map->count, vma->vm_start, vma->vm_end); + + map->count--; + if (0 == map->count) { + struct videobuf_dma_contig_memory *mem; + + dev_dbg(map->q->dev, "munmap %p q=%p\n", map, q); + mutex_lock(&q->vb_lock); + + /* We need first to cancel streams, before unmapping */ + if (q->streaming) + videobuf_queue_cancel(q); + + for (i = 0; i < VIDEO_MAX_FRAME; i++) { + if (NULL == q->bufs[i]) + continue; + + if (q->bufs[i]->map != map) + continue; + + mem = q->bufs[i]->priv; + if (mem) { + /* This callback is called only if kernel has + allocated memory and this memory is mmapped. + In this case, memory should be freed, + in order to do memory unmap. + */ + + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + /* vfree is not atomic - can't be + called with IRQ's disabled + */ + dev_dbg(map->q->dev, "buf[%d] freeing %p\n", + i, mem->vaddr); + + dma_free_coherent(q->dev, mem->size, + mem->vaddr, mem->dma_handle); + mem->vaddr = NULL; + } + + q->bufs[i]->map = NULL; + q->bufs[i]->baddr = 0; + } + + kfree(map); + + mutex_unlock(&q->vb_lock); + } +} + +static struct vm_operations_struct videobuf_vm_ops = { + .open = videobuf_vm_open, + .close = videobuf_vm_close, +}; + +static void *__videobuf_alloc(size_t size) +{ + struct videobuf_dma_contig_memory *mem; + struct videobuf_buffer *vb; + + vb = kzalloc(size + sizeof(*mem), GFP_KERNEL); + if (vb) { + mem = vb->priv = ((char *)vb) + size; + mem->magic = MAGIC_DC_MEM; + } + + return vb; +} + +static void *__videobuf_to_vmalloc(struct videobuf_buffer *buf) +{ + struct videobuf_dma_contig_memory *mem = buf->priv; + + BUG_ON(!mem); + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + return mem->vaddr; +} + +static int __videobuf_iolock(struct videobuf_queue *q, + struct videobuf_buffer *vb, + struct v4l2_framebuffer *fbuf) +{ + struct videobuf_dma_contig_memory *mem = vb->priv; + + BUG_ON(!mem); + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + switch (vb->memory) { + case V4L2_MEMORY_MMAP: + dev_dbg(q->dev, "%s memory method MMAP\n", __func__); + + /* All handling should be done by __videobuf_mmap_mapper() */ + if (!mem->vaddr) { + dev_err(q->dev, "memory is not alloced/mmapped.\n"); + return -EINVAL; + } + break; + case V4L2_MEMORY_USERPTR: + dev_dbg(q->dev, "%s memory method USERPTR\n", __func__); + + /* The only USERPTR currently supported is the one needed for + read() method. + */ + if (vb->baddr) + return -EINVAL; + + mem->size = PAGE_ALIGN(vb->size); + mem->vaddr = dma_alloc_coherent(q->dev, mem->size, + &mem->dma_handle, GFP_KERNEL); + if (!mem->vaddr) { + dev_err(q->dev, "dma_alloc_coherent %ld failed\n", + mem->size); + return -ENOMEM; + } + + dev_dbg(q->dev, "dma_alloc_coherent data is at %p (%ld)\n", + mem->vaddr, mem->size); + break; + case V4L2_MEMORY_OVERLAY: + default: + dev_dbg(q->dev, "%s memory method OVERLAY/unknown\n", + __func__); + return -EINVAL; + } + + return 0; +} + +static int __videobuf_sync(struct videobuf_queue *q, + struct videobuf_buffer *buf) +{ + struct videobuf_dma_contig_memory *mem = buf->priv; + + BUG_ON(!mem); + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + dma_sync_single_for_cpu(q->dev, mem->dma_handle, mem->size, + DMA_FROM_DEVICE); + return 0; +} + +static int __videobuf_mmap_free(struct videobuf_queue *q) +{ + unsigned int i; + + dev_dbg(q->dev, "%s\n", __func__); + for (i = 0; i < VIDEO_MAX_FRAME; i++) { + if (q->bufs[i] && q->bufs[i]->map) + return -EBUSY; + } + + return 0; +} + +static int __videobuf_mmap_mapper(struct videobuf_queue *q, + struct vm_area_struct *vma) +{ + struct videobuf_dma_contig_memory *mem; + struct videobuf_mapping *map; + unsigned int first; + int retval; + unsigned long size, offset = vma->vm_pgoff << PAGE_SHIFT; + + dev_dbg(q->dev, "%s\n", __func__); + if (!(vma->vm_flags & VM_WRITE) || !(vma->vm_flags & VM_SHARED)) + return -EINVAL; + + /* look for first buffer to map */ + for (first = 0; first < VIDEO_MAX_FRAME; first++) { + if (!q->bufs[first]) + continue; + + if (V4L2_MEMORY_MMAP != q->bufs[first]->memory) + continue; + if (q->bufs[first]->boff == offset) + break; + } + if (VIDEO_MAX_FRAME == first) { + dev_dbg(q->dev, "invalid user space offset [offset=0x%lx]\n", + offset); + return -EINVAL; + } + + /* create mapping + update buffer list */ + map = kzalloc(sizeof(struct videobuf_mapping), GFP_KERNEL); + if (!map) + return -ENOMEM; + + q->bufs[first]->map = map; + map->start = vma->vm_start; + map->end = vma->vm_end; + map->q = q; + + q->bufs[first]->baddr = vma->vm_start; + + mem = q->bufs[first]->priv; + BUG_ON(!mem); + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + mem->size = PAGE_ALIGN(q->bufs[first]->bsize); + mem->vaddr = dma_alloc_coherent(q->dev, mem->size, + &mem->dma_handle, GFP_KERNEL); + if (!mem->vaddr) { + dev_err(q->dev, "dma_alloc_coherent size %ld failed\n", + mem->size); + goto error; + } + dev_dbg(q->dev, "dma_alloc_coherent data is at addr %p (size %ld)\n", + mem->vaddr, mem->size); + + /* Try to remap memory */ + + size = vma->vm_end - vma->vm_start; + size = (size < mem->size) ? size : mem->size; + + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + retval = remap_pfn_range(vma, vma->vm_start, + mem->dma_handle >> PAGE_SHIFT, + size, vma->vm_page_prot); + if (retval) { + dev_err(q->dev, "mmap: remap failed with error %d. ", retval); + dma_free_coherent(q->dev, mem->size, + mem->vaddr, mem->dma_handle); + goto error; + } + + vma->vm_ops = &videobuf_vm_ops; + vma->vm_flags |= VM_DONTEXPAND; + vma->vm_private_data = map; + + dev_dbg(q->dev, "mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n", + map, q, vma->vm_start, vma->vm_end, + (long int) q->bufs[first]->bsize, + vma->vm_pgoff, first); + + videobuf_vm_open(vma); + + return 0; + +error: + kfree(map); + return -ENOMEM; +} + +static int __videobuf_copy_to_user(struct videobuf_queue *q, + char __user *data, size_t count, + int nonblocking) +{ + struct videobuf_dma_contig_memory *mem = q->read_buf->priv; + void *vaddr; + + BUG_ON(!mem); + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + BUG_ON(!mem->vaddr); + + /* copy to userspace */ + if (count > q->read_buf->size - q->read_off) + count = q->read_buf->size - q->read_off; + + vaddr = mem->vaddr; + + if (copy_to_user(data, vaddr + q->read_off, count)) + return -EFAULT; + + return count; +} + +static int __videobuf_copy_stream(struct videobuf_queue *q, + char __user *data, size_t count, size_t pos, + int vbihack, int nonblocking) +{ + unsigned int *fc; + struct videobuf_dma_contig_memory *mem = q->read_buf->priv; + + BUG_ON(!mem); + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + if (vbihack) { + /* dirty, undocumented hack -- pass the frame counter + * within the last four bytes of each vbi data block. + * We need that one to maintain backward compatibility + * to all vbi decoding software out there ... */ + fc = (unsigned int *)mem->vaddr; + fc += (q->read_buf->size >> 2) - 1; + *fc = q->read_buf->field_count >> 1; + dev_dbg(q->dev, "vbihack: %d\n", *fc); + } + + /* copy stuff using the common method */ + count = __videobuf_copy_to_user(q, data, count, nonblocking); + + if ((count == -EFAULT) && (pos == 0)) + return -EFAULT; + + return count; +} + +static struct videobuf_qtype_ops qops = { + .magic = MAGIC_QTYPE_OPS, + + .alloc = __videobuf_alloc, + .iolock = __videobuf_iolock, + .sync = __videobuf_sync, + .mmap_free = __videobuf_mmap_free, + .mmap_mapper = __videobuf_mmap_mapper, + .video_copy_to_user = __videobuf_copy_to_user, + .copy_stream = __videobuf_copy_stream, + .vmalloc = __videobuf_to_vmalloc, +}; + +void videobuf_queue_dma_contig_init(struct videobuf_queue *q, + struct videobuf_queue_ops *ops, + struct device *dev, + spinlock_t *irqlock, + enum v4l2_buf_type type, + enum v4l2_field field, + unsigned int msize, + void *priv) +{ + videobuf_queue_core_init(q, ops, dev, irqlock, type, field, msize, + priv, &qops); +} +EXPORT_SYMBOL_GPL(videobuf_queue_dma_contig_init); + +dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf) +{ + struct videobuf_dma_contig_memory *mem = buf->priv; + + BUG_ON(!mem); + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + return mem->dma_handle; +} +EXPORT_SYMBOL_GPL(videobuf_to_dma_contig); + +void videobuf_dma_contig_free(struct videobuf_queue *q, + struct videobuf_buffer *buf) +{ + struct videobuf_dma_contig_memory *mem = buf->priv; + + /* mmapped memory can't be freed here, otherwise mmapped region + would be released, while still needed. In this case, the memory + release should happen inside videobuf_vm_close(). + So, it should free memory only if the memory were allocated for + read() operation. + */ + if ((buf->memory != V4L2_MEMORY_USERPTR) || !buf->baddr) + return; + + if (!mem) + return; + + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + dma_free_coherent(q->dev, mem->size, mem->vaddr, mem->dma_handle); + mem->vaddr = NULL; +} +EXPORT_SYMBOL_GPL(videobuf_dma_contig_free); + +MODULE_DESCRIPTION("helper module to manage video4linux dma contig buffers"); +MODULE_AUTHOR("Magnus Damm"); +MODULE_LICENSE("GPL"); diff --git a/include/media/videobuf-dma-contig.h b/include/media/videobuf-dma-contig.h new file mode 100644 index 0000000..5493866 --- /dev/null +++ b/include/media/videobuf-dma-contig.h @@ -0,0 +1,32 @@ +/* + * helper functions for physically contiguous capture buffers + * + * The functions support hardware lacking scatter gather support + * (i.e. the buffers must be linear in physical memory) + * + * Copyright (c) 2008 Magnus Damm + * + * 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; either version 2 + */ +#ifndef _VIDEOBUF_DMA_CONTIG_H +#define _VIDEOBUF_DMA_CONTIG_H + +#include <linux/dma-mapping.h> +#include <media/videobuf-core.h> + +void videobuf_queue_dma_contig_init(struct videobuf_queue *q, + struct videobuf_queue_ops *ops, + struct device *dev, + spinlock_t *irqlock, + enum v4l2_buf_type type, + enum v4l2_field field, + unsigned int msize, + void *priv); + +dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf); +void videobuf_dma_contig_free(struct videobuf_queue *q, + struct videobuf_buffer *buf); + +#endif /* _VIDEOBUF_DMA_CONTIG_H */ |
