From 36003386f86c0624ae0662a229081ef2b11ac784 Mon Sep 17 00:00:00 2001 From: Alexandre Courbot Date: Thu, 3 Mar 2011 08:04:42 +0000 Subject: serial: sh-sci: fix deadlock when resuming from S3 sleep S3 sleep invokes the shutdown callback of the sh-sci driver, which suspends the clocks until they are reactivated by a call to startup. However, before the latter is invoked, sci_set_termios may be called on the port by uart_resume_port. In such cases it will endlessly wait for the TEND bit to raise, which will never happen since the clocks are disabled. This patch ensures that clocks are enabled when ports registers are manipulated within sci_set_termios. Signed-off-by: Alexandre Courbot Signed-off-by: Paul Mundt --- drivers/tty/serial/sh-sci.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 0257fd5ede52..eb7958c675a8 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1504,6 +1504,9 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, if (likely(baud && port->uartclk)) t = sci_scbrr_calc(s->cfg->scbrr_algo_id, baud, port->uartclk); + if (s->enable) + s->enable(port); + do { status = sci_in(port, SCxSR); } while (!(status & SCxSR_TEND(port))); @@ -1571,6 +1574,9 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, if ((termios->c_cflag & CREAD) != 0) sci_start_rx(port); + + if (s->disable) + s->disable(port); } static const char *sci_type(struct uart_port *port) -- cgit v1.2.3