The patch titled
serial: assert DTR for serial console devices
has been added to the -mm tree. Its filename is
serial-assert-dtr-for-serial-console-devices.patch
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: serial: assert DTR for serial console devices
From: Yinghai Lu <Yinghai.Lu@xxxxxxx>
Some RS-232 devices require DTR to be asserted before they can be used. DTR
is normally asserted in uart_startup() when the port is opened. But we don't
actually open serial console ports, so assert DTR when the port is added.
BTW:
earlyprintk and early_uart are hard coded to set DTR/RTS.
Signed-off-by: Yinghai Lu <yinghai.lu@xxxxxxx>
Acked-by: Russell King <rmk@xxxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxx>
Cc: Bjorn Helgaas <bjorn.helgaas@xxxxxx>
Cc: Gerd Hoffmann <kraxel@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/serial/serial_core.c | 6 ++++++
1 files changed, 6 insertions(+)
diff -puN drivers/serial/serial_core.c~serial-assert-dtr-for-serial-console-devices drivers/serial/serial_core.c
--- a/drivers/serial/serial_core.c~serial-assert-dtr-for-serial-console-devices
+++ a/drivers/serial/serial_core.c
@@ -1918,6 +1918,12 @@ uart_set_options(struct uart_port *port,
if (flow == 'r')
termios.c_cflag |= CRTSCTS;
+ /*
+ * some uarts on other side don't support no flow control.
+ * So we set * DTR in host uart to make them happy
+ */
+ port->mctrl |= TIOCM_DTR;
+
port->ops->set_termios(port, &termios, NULL);
co->cflag = termios.c_cflag;
_
Patches currently in -mm which might be from Yinghai.Lu@xxxxxxx are
console-more-buf-for-index-parsing.patch
console-console-handover-to-preferred-console.patch
serial-convert-early_uart-to-earlycon-for-8250.patch
serial-convert-early_uart-to-earlycon-for-8250-fix.patch
serial-assert-dtr-for-serial-console-devices.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
