From 011bd05d1f5d99eeb91e8a6f81f00654a2b8d3d1 Mon Sep 17 00:00:00 2001 From: Sergey Organov Date: Wed, 26 Jun 2019 17:11:30 +0300 Subject: [PATCH] serial: imx: set_termios(): preserve RTS state imx_set_termios() cleared RTS on every call, now fixed. Reviewed-by: Sascha Hauer Tested-by: Sascha Hauer Signed-off-by: Sergey Organov Link: https://lore.kernel.org/r/1561558293-7683-5-git-send-email-sorganov@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/imx.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 1cb891b4eaa0..57d6e6ba556e 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1562,7 +1562,14 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, spin_lock_irqsave(&sport->port.lock, flags); - ucr2 = UCR2_SRST | UCR2_IRTS; + /* + * Read current UCR2 and save it for future use, then clear all the bits + * except those we will or may need to preserve. + */ + old_ucr2 = imx_uart_readl(sport, UCR2); + ucr2 = old_ucr2 & (UCR2_TXEN | UCR2_RXEN | UCR2_ATEN | UCR2_CTS); + + ucr2 |= UCR2_SRST | UCR2_IRTS; if ((termios->c_cflag & CSIZE) == CS8) ucr2 |= UCR2_WS; @@ -1631,7 +1638,6 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, imx_uart_writel(sport, old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN), UCR1); - old_ucr2 = imx_uart_readl(sport, UCR2); imx_uart_writel(sport, old_ucr2 & ~UCR2_ATEN, UCR2); while (!(imx_uart_readl(sport, USR2) & USR2_TXDC)) @@ -1639,7 +1645,6 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, /* then, disable everything */ imx_uart_writel(sport, old_ucr2 & ~(UCR2_TXEN | UCR2_RXEN | UCR2_ATEN), UCR2); - old_ucr2 &= (UCR2_TXEN | UCR2_RXEN | UCR2_ATEN); /* custom-baudrate handling */ div = sport->port.uartclk / (baud * 16); @@ -1677,8 +1682,7 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, imx_uart_writel(sport, old_ucr1, UCR1); - /* set the parity, stop bits and data size */ - imx_uart_writel(sport, ucr2 | old_ucr2, UCR2); + imx_uart_writel(sport, ucr2, UCR2); if (UART_ENABLE_MS(&sport->port, termios->c_cflag)) imx_uart_enable_ms(&sport->port);