node-drivers/base-driver/drivers/vca/plx87xx/plx_main.c
static int plx_request_dma_chan(struct plx_device *xdev)
{
	dma_cap_mask_t mask;

	dma_cap_zero(mask);
	dma_cap_set(DMA_MEMCPY, mask);

	xdev->dma_ch = dma_request_channel(mask, plx_dma_filter,
					   &xdev->pdev->dev);
	dev_info(&xdev->pdev->dev, "DMA channels # %d\n", !!xdev->dma_ch);
	return !!xdev->dma_ch;
}
/**
 * plx_request_dma_chan - Request DMA channel
 * @xdev: pointer to plx_device instance
 *
 * returns true if a DMA channel was acquired
 */
Request DMA channel
@xdev: pointer to plx_device instance

returns true if a DMA channel was acquired
Request DMA channel @xdev : pointer to plx_device instance returns true if a DMA channel was acquired
static int plx_request_dma_chan(struct plx_device *xdev)
{
	dma_cap_mask_t mask;
	dma_cap_zero(mask);
	dma_cap_set(DMA_MEMCPY, mask);
	xdev->dma_ch = dma_request_channel(mask, plx_dma_filter,
					   &xdev->pdev->dev);
	dev_info(&xdev->pdev->dev, "DMA channels # %d\n", !!xdev->dma_ch);
	return !!xdev->dma_ch;
}
static int plx_request_dma_chan ( struct plx_device * xdev ) { dma_cap_mask_t mask ; dma_cap_zero ( mask ) ; dma_cap_set ( DMA_MEMCPY , mask ) ; xdev -> dma_ch = dma_request_channel ( mask , plx_dma_filter , & xdev -> pdev -> dev ) ; dev_info ( & xdev -> pdev -> dev , " \n " , ! ! xdev -> dma_ch ) ; return ! ! xdev -> dma_ch ; }
plx_request_dma_chan - Request DMA channel
 @xdev: pointer to plx_device instance
plx_request_dma_chan - Request DMA channel @xdev : pointer to plx_device instance