From: Huang Shijie Date: Fri, 19 Sep 2014 07:33:12 +0000 (+0800) Subject: serial: imx: terminate the RX DMA when the UART is suspending X-Git-Tag: v3.18-rc1~129^2~12 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=45564a6656b4944fa90aabd59f8ec082e8f7a969;p=linux.git serial: imx: terminate the RX DMA when the UART is suspending When the uart port is suspending, the RX data is useless. So in this case, we can terminate the RX DMA right now. Signed-off-by: Huang Shijie Signed-off-by: Fugang Duan Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index c7683d747c18..db749f768ac4 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -436,12 +436,14 @@ static void imx_stop_rx(struct uart_port *port) struct imx_port *sport = (struct imx_port *)port; unsigned long temp; - /* - * We are maybe in the SMP context, so if the DMA TX thread is running - * on other cpu, we have to wait for it to finish. - */ - if (sport->dma_is_enabled && sport->dma_is_rxing) - return; + if (sport->dma_is_enabled && sport->dma_is_rxing) { + if (sport->port.suspended) { + dmaengine_terminate_all(sport->dma_chan_rx); + sport->dma_is_rxing = 0; + } else { + return; + } + } temp = readl(sport->port.membase + UCR2); writel(temp & ~UCR2_RXEN, sport->port.membase + UCR2);