On 7/3/2022 11:40 PM, Jiri Slaby wrote:
On 29. 06. 22, 18:02, Florian Fainelli wrote:
From: Doug Berger <opendmb@xxxxxxxxx>
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@xxxxxxxxx>
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
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..b9cea38c8aff 100644
--- a/drivers/tty/serial/8250/8250_bcm7271.c
+++ b/drivers/tty/serial/8250/8250_bcm7271.c
...
@@ -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;
+ spin_unlock_irqrestore(&port->lock, flags);
+ port->ops->set_mctrl(port, port->mctrl);
Calling ->set_mctrl w/o port->lock doesn't look really safe.
Good point, I will check with Doug whether this was intentional and if
so, why, and if not why should we move it up under the spinlock.
Thanks!
--
Florian