Karl Beldan wrote: > To tx a chunk of data from the SoC => network device, we : > - prepare a buffer with a leading header embedding a pattern, > - trigger the xfer and wait for an irq > // The device updates the pattern and then triggers an irq > - upon irq we check the pattern for the xfer completion > > I was expecting the following to work: > addr = dma_map_single(dev, buffer, size, DMA_TO_DEVICE);
Of both the CPU and the device write to the buffer, you must use DMA_BIDIRECTIONAL. Regards, Clemens -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/