The two patches in this series add DMA support to the sh-sci SCI(F) serial driver. The worst problem is partial reception. Since we don't know in advance how many bytes we're going to receive, we submit a DMA buffer _and_ enable the Rx interrupt. When data arrives, we get an interrupt and the data is written into DMA buffers. In the ISR we then set a timeout, if within this time we get no DMA completion callback, we have a partial buffer. Unfortunately, dmaengine API currently doesn't support retrieving partially received DMA buffers, therefore we have to hijack the .device_terminate_all() call to collect the data. A better approach would be to add a stop-transfer / collect-partial call to the API. Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
