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| author | Sergey Organov <sorganov@gmail.com> | 2019-07-26 21:52:40 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-09-04 12:43:46 +0200 |
| commit | 197540dc8301a296e8ae7aa062f9f61f047eea05 (patch) | |
| tree | 57c0730d640a96aac2e4a66acb7b5208d14fb3f4 /drivers/tty/serial | |
| parent | a25aee902e666e8cc41e33754f13c69a979dd67f (diff) | |
| download | blackbird-op-linux-197540dc8301a296e8ae7aa062f9f61f047eea05.tar.gz blackbird-op-linux-197540dc8301a296e8ae7aa062f9f61f047eea05.zip | |
serial: imx: set_mctrl(): correctly restore autoRTS state
imx_uart_set_mctrl() happened to set UCR2_CTSC bit whenever TIOCM_RTS
was set, no matter if RTS/CTS handshake is enabled or not. Now fixed by
turning handshake on only when CRTSCTS bit for the port is set.
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Sergey Organov <sorganov@gmail.com>
Link: https://lore.kernel.org/r/1564167161-3972-3-git-send-email-sorganov@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
| -rw-r--r-- | drivers/tty/serial/imx.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 32f36d86a960..059ba354d17e 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -974,10 +974,22 @@ static void imx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) if (!(port->rs485.flags & SER_RS485_ENABLED)) { u32 ucr2; + /* + * Turn off autoRTS if RTS is lowered and restore autoRTS + * setting if RTS is raised. + */ ucr2 = imx_uart_readl(sport, UCR2); ucr2 &= ~(UCR2_CTS | UCR2_CTSC); - if (mctrl & TIOCM_RTS) - ucr2 |= UCR2_CTS | UCR2_CTSC; + if (mctrl & TIOCM_RTS) { + ucr2 |= UCR2_CTS; + /* + * UCR2_IRTS is unset if and only if the port is + * configured for CRTSCTS, so we use inverted UCR2_IRTS + * to get the state to restore to. + */ + if (!(ucr2 & UCR2_IRTS)) + ucr2 |= UCR2_CTSC; + } imx_uart_writel(sport, ucr2, UCR2); } |
