    void unmap_descbuffer(struct b43_dmaring *ring,
			  dma_addr_t addr, size_t len, int tx)
{
	if (tx) {
		dma_unmap_single(ring->dev->dev->dma_dev,
				 addr, len, DMA_TO_DEVICE);
	} else {
		dma_unmap_single(ring->dev->dev->dma_dev,
				 addr, len, DMA_FROM_DEVICE);
	}
}
    void unmap_descbuffer(struct b43_dmaring *ring,
			  dma_addr_t addr, size_t len, int tx)
{
	if (tx) {
		dma_unmap_single(ring->dev->dev->dma_dev,
				 addr, len, DMA_TO_DEVICE);
	} else {
		dma_unmap_single(ring->dev->dev->dma_dev,
				 addr, len, DMA_FROM_DEVICE);
	}
}