From bc2be239feef9ac9fc8ad17adf7c03b353f6546f Mon Sep 17 00:00:00 2001
From: Fabio Estevam <fabio.estevam@nxp.com>
Date: Mon, 30 Jan 2017 09:12:12 -0200
Subject: [PATCH] serial: imx: Fix the CTS_B polarity in RS485 mode
When userspace passes the SER_RS485_RTS_ON_SEND flag it means that the
CTS_B pin should go to logic level high before the transmission begins.
CTS_B goes to logic level high when both CTSC and CTS bits are cleared.
When userspace passes the SER_RS485_RTS_AFTER_SEND flag it means that the
CTS_B pin should go to logic level low after the transmission finishes.
CTS_B goes to logic level low when CTSC bit is cleared and CTS bit is set.
So fix the CTS_B polarity logic.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/serial/imx.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 29dd57c51706c..e3e152cbc75e7 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -336,15 +336,15 @@ static void imx_port_ucrs_restore(struct uart_port *port,
static void imx_port_rts_active(struct imx_port *sport, unsigned long *ucr2)
{
- *ucr2 &= ~UCR2_CTSC;
- *ucr2 |= UCR2_CTS;
+ *ucr2 &= ~(UCR2_CTSC | UCR2_CTS);
mctrl_gpio_set(sport->gpios, sport->port.mctrl | TIOCM_RTS);
}
static void imx_port_rts_inactive(struct imx_port *sport, unsigned long *ucr2)
{
- *ucr2 &= ~(UCR2_CTSC | UCR2_CTS);
+ *ucr2 &= ~UCR2_CTSC;
+ *ucr2 |= UCR2_CTS;
mctrl_gpio_set(sport->gpios, sport->port.mctrl & ~TIOCM_RTS);
}
--
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