diff options
Diffstat (limited to 'drivers/char/bsr.c')
| -rw-r--r-- | drivers/char/bsr.c | 25 |
1 files changed, 19 insertions, 6 deletions
diff --git a/drivers/char/bsr.c b/drivers/char/bsr.c index 7d9fd8a8dfd0..c02db01f736e 100644 --- a/drivers/char/bsr.c +++ b/drivers/char/bsr.c @@ -27,6 +27,7 @@ #include <linux/cdev.h> #include <linux/list.h> #include <linux/mm.h> +#include <asm/pgtable.h> #include <asm/io.h> /* @@ -118,15 +119,22 @@ static int bsr_mmap(struct file *filp, struct vm_area_struct *vma) { unsigned long size = vma->vm_end - vma->vm_start; struct bsr_dev *dev = filp->private_data; + int ret; - if (size > dev->bsr_len || (size & (PAGE_SIZE-1))) - return -EINVAL; - - vma->vm_flags |= (VM_IO | VM_DONTEXPAND); vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - if (io_remap_pfn_range(vma, vma->vm_start, dev->bsr_addr >> PAGE_SHIFT, - size, vma->vm_page_prot)) + /* check for the case of a small BSR device and map one 4k page for it*/ + if (dev->bsr_len < PAGE_SIZE && size == PAGE_SIZE) + ret = remap_4k_pfn(vma, vma->vm_start, dev->bsr_addr >> 12, + vma->vm_page_prot); + else if (size <= dev->bsr_len) + ret = io_remap_pfn_range(vma, vma->vm_start, + dev->bsr_addr >> PAGE_SHIFT, + size, vma->vm_page_prot); + else + return -EINVAL; + + if (ret) return -EAGAIN; return 0; @@ -206,6 +214,11 @@ static int bsr_add_node(struct device_node *bn) cur->bsr_stride = bsr_stride[i]; cur->bsr_dev = MKDEV(bsr_major, i + total_bsr_devs); + /* if we have a bsr_len of > 4k and less then PAGE_SIZE (64k pages) */ + /* we can only map 4k of it, so only advertise the 4k in sysfs */ + if (cur->bsr_len > 4096 && cur->bsr_len < PAGE_SIZE) + cur->bsr_len = 4096; + switch(cur->bsr_bytes) { case 8: cur->bsr_type = BSR_8; |