From: Doug Berger opendmb@gmail.com
[ Upstream commit 3182efd036c1b955403d131258234896cbd9fbeb ]
Commit 9cabe26e65a8 ("serial: 8250_bcm7271: UART errors after resuming from S2") prevented an early enabling of RTS during resume, but it did not actively restore the RTS state after resume.
Fixes: 9cabe26e65a8 ("serial: 8250_bcm7271: UART errors after resuming from S2") Signed-off-by: Doug Berger opendmb@gmail.com Signed-off-by: Florian Fainelli f.fainelli@gmail.com Link: https://lore.kernel.org/r/20220714031316.404918-1-f.fainelli@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/8250/8250_bcm7271.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_bcm7271.c b/drivers/tty/serial/8250/8250_bcm7271.c index 9b878d023dac..8efdc271eb75 100644 --- a/drivers/tty/serial/8250/8250_bcm7271.c +++ b/drivers/tty/serial/8250/8250_bcm7271.c @@ -1139,16 +1139,19 @@ static int __maybe_unused brcmuart_suspend(struct device *dev) struct brcmuart_priv *priv = dev_get_drvdata(dev); struct uart_8250_port *up = serial8250_get_port(priv->line); struct uart_port *port = &up->port; - - serial8250_suspend_port(priv->line); - clk_disable_unprepare(priv->baud_mux_clk); + unsigned long flags;
/* * This will prevent resume from enabling RTS before the - * baud rate has been resored. + * baud rate has been restored. */ + spin_lock_irqsave(&port->lock, flags); priv->saved_mctrl = port->mctrl; - port->mctrl = 0; + port->mctrl &= ~TIOCM_RTS; + spin_unlock_irqrestore(&port->lock, flags); + + serial8250_suspend_port(priv->line); + clk_disable_unprepare(priv->baud_mux_clk);
return 0; } @@ -1158,6 +1161,7 @@ static int __maybe_unused brcmuart_resume(struct device *dev) struct brcmuart_priv *priv = dev_get_drvdata(dev); struct uart_8250_port *up = serial8250_get_port(priv->line); struct uart_port *port = &up->port; + unsigned long flags; int ret;
ret = clk_prepare_enable(priv->baud_mux_clk); @@ -1180,7 +1184,15 @@ static int __maybe_unused brcmuart_resume(struct device *dev) start_rx_dma(serial8250_get_port(priv->line)); } serial8250_resume_port(priv->line); - port->mctrl = priv->saved_mctrl; + + if (priv->saved_mctrl & TIOCM_RTS) { + /* Restore RTS */ + spin_lock_irqsave(&port->lock, flags); + port->mctrl |= TIOCM_RTS; + port->ops->set_mctrl(port, port->mctrl); + spin_unlock_irqrestore(&port->lock, flags); + } + return 0; }