于 2012年12月13日 00:31, Steffen Trumtrar 写道: > With the patch "serial: mxs-auart: fix the wrong RTS hardware flow control" the > mainline mxs-uart driver now sets RTSEN only when hardware flow control is > enabled via software. It is not possible any longer to set RTS manually via > software. However, the manual modification is a valid operation. > Regain the possibility to set RTS via software and only set RTSEN when hardware Is there any user case to set the RTS via software? I am confused at this. > flow control is explicitly enabled via settermios cflag CRTSCTS. > > Signed-off-by: Steffen Trumtrar <s.trumtrar@xxxxxxxxxxxxxx> > --- > drivers/tty/serial/mxs-auart.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c > index 6db23b0..9b62c4b 100644 > --- a/drivers/tty/serial/mxs-auart.c > +++ b/drivers/tty/serial/mxs-auart.c > @@ -412,10 +412,12 @@ static void mxs_auart_set_mctrl(struct uart_port *u, unsigned mctrl) > > u32 ctrl = readl(u->membase + AUART_CTRL2); > > - ctrl &= ~AUART_CTRL2_RTSEN; > + ctrl &= ~(AUART_CTRL2_RTSEN | AUART_CTRL2_RTS); > if (mctrl & TIOCM_RTS) { > if (tty_port_cts_enabled(&u->state->port)) > ctrl |= AUART_CTRL2_RTSEN; > + else > + ctrl |= AUART_CTRL2_RTS; > } > > s->ctrl = mctrl; > @@ -678,6 +680,10 @@ static void mxs_auart_settermios(struct uart_port *u, > } > ctrl2 |= AUART_CTRL2_CTSEN | AUART_CTRL2_RTSEN; > } else { > + u->flags |= ASYNC_CTS_FLOW; > + ctrl2 |= AUART_CTRL2_CTSEN | AUART_CTRL2_RTSEN; > + } else { > + u->flags &= ~ASYNC_CTS_FLOW; bug. Your code adds TWO "else" here. thanks Huang Shijie > ctrl2 &= ~(AUART_CTRL2_CTSEN | AUART_CTRL2_RTSEN); > } > -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html