On Mon, May 14, 2007 at 12:04:44PM -0700, Yinghai Lu wrote: > Russell King wrote: > >There may be some sense, however, in allowing DTR to be permanently > >raised for serial consoles. However, I would err on caution since > >DTR is used to reliably instruct modems to drop the line, so making > >such a change would be undesirable for those folk. > > > please check following is OK.
Still wrong, and unfortunately you haven't understood what I was saying at all because this is worse. ;( Do not put the code in serial8250_set_termios. It is the wrong place. > > YH > > [PATCH] serial: set DTR in uart for kernel serial console > > Some UARTs on other side need host uart DTR is set, otherwise will not > receive char from the host that kernel is runing during kernel boot stage. > > BTW: > earlyprintk and early_uart are hard coded to set DTR/RTS. > > Signed-off-by: Yinghai Lu <[EMAIL PROTECTED]> > Cc: Russell King <[EMAIL PROTECTED]> > Cc: Andi Kleen <[EMAIL PROTECTED]> > Cc: Bjorn Helgaas <[EMAIL PROTECTED]> > > *diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c* > index 48e259a..29c051c 100644 > *--- a/drivers/serial/8250.c* > *+++ b/drivers/serial/8250.c* > @@ -2154,6 +2154,12 @@ serial8250_set_termios(struct uart_port *port, > struct ktermios *termios, > } > serial_outp(up, UART_FCR, fcr); /* set fcr */ > } > + > + /* some uarts on other side don't support no flow control. So we set > + * DTR in host uart to make them happy > + */ > + up->port.mctrl |= TIOCM_DTR; > + > serial8250_set_mctrl(&up->port, up->port.mctrl); > spin_unlock_irqrestore(&up->port.lock, flags); > } > -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
