From mboxrd@z Thu Jan 1 00:00:00 1970 From: Troy Kisky Subject: [PATCH 1/1] tty: serial: imx: disable ageing timer interrupt if dma in use Date: Fri, 6 Oct 2017 18:46:48 -0700 Message-ID: <20171007014648.6989-1-troy.kisky@boundarydevices.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: gregkh@linuxfoundation.org Cc: Troy Kisky , linux-serial@vger.kernel.org, u.kleine-koenig@pengutronix.de, fabio.estevam@nxp.com, linux-arm-kernel@lists.infradead.org, l.stach@pengutronix.de List-Id: linux-serial@vger.kernel.org Since commit 4dec2f119e86 ("imx-serial: RX DMA startup latency") the interrupt routine no longer will start rx dma. Signed-off-by: Troy Kisky --- drivers/tty/serial/imx.c | 34 ++-------------------------------- 1 file changed, 2 insertions(+), 32 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index dfeff3951f93..15b0ecb4cf60 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -732,29 +732,6 @@ static void imx_disable_rx_int(struct imx_port *sport) } static void clear_rx_errors(struct imx_port *sport); -static int start_rx_dma(struct imx_port *sport); -/* - * If the RXFIFO is filled with some data, and then we - * arise a DMA operation to receive them. - */ -static void imx_dma_rxint(struct imx_port *sport) -{ - unsigned long temp; - unsigned long flags; - - spin_lock_irqsave(&sport->port.lock, flags); - - temp = readl(sport->port.membase + USR2); - if ((temp & USR2_RDR) && !sport->dma_is_rxing) { - - imx_disable_rx_int(sport); - - /* tell the DMA to receive the data. */ - start_rx_dma(sport); - } - - spin_unlock_irqrestore(&sport->port.lock, flags); -} /* * We have a modem side uart, so the meanings of RTS and CTS are inverted. @@ -816,11 +793,8 @@ static irqreturn_t imx_int(int irq, void *dev_id) sts = readl(sport->port.membase + USR1); sts2 = readl(sport->port.membase + USR2); - if (sts & (USR1_RRDY | USR1_AGTIM)) { - if (sport->dma_is_enabled) - imx_dma_rxint(sport); - else - imx_rxint(irq, dev_id); + if (!sport->dma_is_enabled && (sts & (USR1_RRDY | USR1_AGTIM))) { + imx_rxint(irq, dev_id); ret = IRQ_HANDLED; } @@ -1207,10 +1181,6 @@ static void imx_enable_dma(struct imx_port *sport) temp |= UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN; writel(temp, sport->port.membase + UCR1); - temp = readl(sport->port.membase + UCR2); - temp |= UCR2_ATEN; - writel(temp, sport->port.membase + UCR2); - imx_setup_ufcr(sport, TXTL_DMA, RXTL_DMA); sport->dma_is_enabled = 1; -- 2.11.0