diff options
| author | Ian Abbott <abbotti@mev.co.uk> | 2014-09-12 10:04:44 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-09-19 15:36:25 -0700 |
| commit | 75fbdbf61dd9f68a28a5e233ad1ccdda7c6f94e8 (patch) | |
| tree | 0bcac831a4c3d01984829418e75203c35171b056 /drivers/staging/comedi/drivers/adl_pci9118.c | |
| parent | f39f87e9ea944ca07b53d8261ba60bfbf4f097da (diff) | |
staging: comedi: adl_pci9118: use dma_alloc_coherent()
Use `dma_alloc_coherent()` to allocate the DMA buffers instead of
using `__get_free_pages()` to allocate and `virt_to_bus()` to get the
hardware address. The coherent buffers are fairly small - at most 4
pages (although there are two of them). Use of `virt_to_bus()` is
discouraged.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/comedi/drivers/adl_pci9118.c')
| -rw-r--r-- | drivers/staging/comedi/drivers/adl_pci9118.c | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/drivers/staging/comedi/drivers/adl_pci9118.c b/drivers/staging/comedi/drivers/adl_pci9118.c index 6ab9e0a27588..e18fd9569a2b 100644 --- a/drivers/staging/comedi/drivers/adl_pci9118.c +++ b/drivers/staging/comedi/drivers/adl_pci9118.c @@ -204,11 +204,10 @@ static const struct pci9118_boardinfo pci9118_boards[] = { }; struct pci9118_dmabuf { - unsigned long virt; /* virtual address of buffer */ - unsigned long hw; /* hardware (bus) address of buffer */ + unsigned short *virt; /* virtual address of buffer */ + dma_addr_t hw; /* hardware (bus) address of buffer */ unsigned int size; /* size of dma buffer in bytes */ unsigned int use_size; /* which size we may now use for transfer */ - int order; /* log2 number of pages in buffer */ }; struct pci9118_private { @@ -475,12 +474,11 @@ static unsigned int defragment_dma_buffer(struct comedi_device *dev, static int move_block_from_dma(struct comedi_device *dev, struct comedi_subdevice *s, - unsigned long virt_addr, + unsigned short *dma_buffer, unsigned int num_samples) { struct pci9118_private *devpriv = dev->private; struct comedi_cmd *cmd = &s->async->cmd; - unsigned short *dma_buffer = (unsigned short *)virt_addr; unsigned int num_bytes; num_samples = defragment_dma_buffer(dev, s, dma_buffer, num_samples); @@ -1485,15 +1483,15 @@ static void pci9118_alloc_dma(struct comedi_device *dev) for (i = 0; i < 2; i++) { dmabuf = &devpriv->dmabuf[i]; for (order = 2; order >= 0; order--) { - dmabuf->virt = __get_free_pages(GFP_KERNEL, order); + dmabuf->virt = + dma_alloc_coherent(dev->hw_dev, PAGE_SIZE << order, + &dmabuf->hw, GFP_KERNEL); if (dmabuf->virt) break; } if (!dmabuf->virt) break; - dmabuf->order = order; dmabuf->size = PAGE_SIZE << order; - dmabuf->hw = virt_to_bus((void *)dmabuf->virt); if (i == 0) devpriv->master = 1; @@ -1513,8 +1511,10 @@ static void pci9118_free_dma(struct comedi_device *dev) for (i = 0; i < 2; i++) { dmabuf = &devpriv->dmabuf[i]; - if (dmabuf->virt) - free_pages(dmabuf->virt, dmabuf->order); + if (dmabuf->virt) { + dma_free_coherent(dev->hw_dev, dmabuf->size, + dmabuf->virt, dmabuf->hw); + } } } |