Commit 4139fd76 authored Sep 28, 2017 by Romain Perier Committed by Greg Kroah-Hartman Oct 03, 2017

serial: imx: only set dma_is_rxing when DMA starts



The variable dma_is_rxing is currently set to 1 in imx_disable_rx_int().
This is problematic as:

- whilst imx_disable_rx_int() is currently always called before
  start_rx_dma() this dependency isn't obvious.
- start_rx_dma() does error checking and might exit without
  enabling DMA. Currently this will result in dma_is_rxing suggesting
  that DMA is being used for recieving.

To avoid these issues, move the setting of dma_is_rxing to
start_rx_dma() when appropriate.

Signed-off-by: Romain Perier <romain.perier@collabora.com>
Signed-off-by: Martyn Welch <martyn.welch@collabora.co.uk>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 177b508f

drivers/tty/serial/imx.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -716,8 +716,6 @@ static void imx_disable_rx_int(struct imx_port *sport)
		{
		unsigned long temp;

		sport->dma_is_rxing = 1;

		/* disable the receiver ready and aging timer interrupts */
		temp = readl(sport->port.membase + UCR1);
		temp &= ~(UCR1_RRDYEN);
		@@ -1076,6 +1074,7 @@ static int start_rx_dma(struct imx_port *sport)
		desc->callback_param = sport;

		dev_dbg(dev, "RX: prepare for the DMA.\n");
		sport->dma_is_rxing = 1;
		sport->rx_cookie = dmaengine_submit(desc);
		dma_async_issue_pending(chan);
		return 0;

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