Hello,
On Thursday, July 26, 2012 1:13 PM Hideki EIRAKU wrote:
Previously the vb2_dma_contig_mmap() function was using a dma_addr_t as a physical address. The two addressses are not necessarily the same. For example, when using the IOMMU funtion on certain platforms, dma_addr_t addresses are not directly mappable physical address. dma_mmap_coherent() maps the address correctly. It is available on ARM platforms.
Signed-off-by: Hideki EIRAKU hdk@igel.co.jp
drivers/media/video/videobuf2-dma-contig.c | 18 ++++++++++++++++++ 1 files changed, 18 insertions(+), 0 deletions(-)
diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma- contig.c index 4b71326..4dc85ab 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -101,14 +101,32 @@ static unsigned int vb2_dma_contig_num_users(void *buf_priv) static int vb2_dma_contig_mmap(void *buf_priv, struct vm_area_struct *vma) { struct vb2_dc_buf *buf = buf_priv; +#ifdef ARCH_HAS_DMA_MMAP_COHERENT
- int ret;
+#endif
if (!buf) { printk(KERN_ERR "No buffer to map\n"); return -EINVAL; }
+#ifdef ARCH_HAS_DMA_MMAP_COHERENT
- vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
The above line is not needed. It is up to dma_mmap_coherent() / dma_mmap_attrs() to set page protection bits which match requested type of dma buffer mapping.
- ret = dma_mmap_coherent(buf->conf->dev, vma, buf->vaddr, buf->dma_addr,
buf->size);- if (ret) {
pr_err("Remapping memory failed, error: %d\n", ret);return ret;- }
- vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
- vma->vm_private_data = &buf->handler;
- vma->vm_ops = &vb2_common_vm_ops;
- vma->vm_ops->open(vma);
- return 0;
+#else return vb2_mmap_pfn_range(vma, buf->dma_addr, buf->size, &vb2_common_vm_ops, &buf->handler); +#endif }
static void *vb2_dma_contig_get_userptr(void *alloc_ctx, unsigned long vaddr,
Best regards