On Tue, May 27, 2014 at 10:35:36AM +0200, Ludovic Desroches wrote: > +static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec, > + struct of_dma *of_dma) > +{ > + struct at_xdmac_chan *atchan; > + struct dma_chan *chan; > + dma_cap_mask_t mask; > + struct platform_device *pdev = of_find_device_by_node(dma_spec->np); No need to search through all the device nodes, you can look up the device from of_dma->of_dma_data. > + if (dma_spec->args_count != 2) { > + dev_err(&pdev->dev, "dma phandler args: bad number of args\n"); > + return NULL; > + } > + > + dma_cap_zero(mask); > + dma_cap_set(DMA_SLAVE, mask); > + chan = dma_request_channel(mask, NULL, NULL); > + if (!chan) { > + dev_err(&pdev->dev, "can't get a dma channel\n"); > + return NULL; > + } You must use dma_get_any_slave_channel. dma_request_channel gives you a channel from a random dma engine that is present in the system, not necessarily the one you are managing here. Arnd -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html