From mboxrd@z Thu Jan 1 00:00:00 1970 From: romain.perier@collabora.com (Romain Perier) Date: Wed, 5 Jul 2017 15:07:01 +0200 Subject: [PATCH v2 1/6] serial: imx: only set DMA rx-ing when DMA starts In-Reply-To: <20170705130706.10388-1-romain.perier@collabora.com> References: <20170705130706.10388-1-romain.perier@collabora.com> Message-ID: <20170705130706.10388-2-romain.perier@collabora.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Nandor Han Avoid the situation when `dma_is_rxing` could incorrectly signal that DMA RX channel is receiving data in case DMA preparation or sg mapping fails. This commit fixes the issues by moving the assignment of dma_is_rxing out of imx_disable_rx_int(), then the variable is set to 1 from start_rx_dma() only when the preparation is correctly done. Signed-off-by: Nandor Han Signed-off-by: Romain Perier --- drivers/tty/serial/imx.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 3bae4ea..01df430 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -729,8 +729,6 @@ 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); @@ -1083,6 +1081,7 @@ 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; -- 1.8.3.1