[PATCH] imx-serial: Reduce RX DMA startup latency when opening for reading

2017-04-07 Thread Peter Senna Tschudin
Reduce RX DMA start latency for the first reception when port is opened for reading. Instead of waiting for an interrupt signaling data on RX FIFO or data too old on RX FIFO, start RX DMA immediately when the serial port is opened for reading. Before this patch, the average RX DMA latency for the

[PATCH] imx-serial: Reduce RX DMA startup latency when opening for reading

2017-04-07 Thread Peter Senna Tschudin
Reduce RX DMA start latency for the first reception when port is opened for reading. Instead of waiting for an interrupt signaling data on RX FIFO or data too old on RX FIFO, start RX DMA immediately when the serial port is opened for reading. Before this patch, the average RX DMA latency for the