[PATCH 1/1] tty: serial: imx: disable ageing timer interrupt if dma in use
From: Han, Nandor GE Healthcare <hidden>
Date: 2017-10-11 06:22:53
Also in:
linux-serial
-----Original Message-----
From: linux-serial-owner at vger.kernel.org [mailto:linux-serial-
owner at vger.kernel.org] On Behalf Of Troy Kisky
Sent: 07 October 2017 04:47
To: gregkh at linuxfoundation.org
Cc: fabio.estevam at nxp.com; l.stach at pengutronix.de; u.kleine-
koenig at pengutronix.de; linux-serial at vger.kernel.org; linux-arm-
kernel at lists.infradead.org; Troy Kisky [off-list ref]
Subject: EXT: [PATCH 1/1] tty: serial: imx: disable ageing timer interrupt if
dma in use
Since commit 4dec2f119e86 ("imx-serial: RX DMA startup latency")
the interrupt routine no longer will start rx dma.I think you have 2 commits here: - one that disables ageing timer when DMA is in use - one that cleans the leftovers after 4dec2f119e86.
quoted hunk ↗ jump to hunk
Signed-off-by: Troy Kisky <redacted> --- 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 indexdfeff3951f93..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);
I don't think we need the check `!sport->dma_is_enabled ` since RRDY and AGTIM interrupts should be disable when DMA is enabled.
quoted hunk ↗ jump to hunk
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); -
I think this should be moved to imx_startup. At least RRDY is configured there. <snip> Regards, Nandor