On 07. 04. 22, 9:25, Vijaya Krishna Nivarthi wrote:
For the case of console_suspend disabled, if back to back suspend/resume
test is executed, at the end of test, sometimes console would appear to
be frozen not responding to input. This would happen because, for
console_suspend disabled, suspend/resume routines only turn resources
off/on but don't do a port close/open.
As a result, during resume, some rx transactions come in before system is
ready, malfunction of rx happens in turn resulting in console appearing
to be stuck.
Do a stop_rx in suspend sequence to prevent this. start_rx is already
present in resume sequence as part of call to set_termios which does a
stop_rx/start_rx.
So why is it OK for every other driver? Should uart_suspend_port() be
fixed instead?
Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@xxxxxxxxxxx>
---
v3: swapped the order of conditions to be more human readable
v2: restricted patch to contain only stop_rx in suspend sequence
v1: intial patch contained 2 additional unrelated changes in vicinity
---
drivers/tty/serial/qcom_geni_serial.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 1543a60..53723d2 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -1481,6 +1481,10 @@ static int __maybe_unused qcom_geni_serial_sys_suspend(struct device *dev)
struct uart_port *uport = &port->uport;
struct qcom_geni_private_data *private_data = uport->private_data;
+ /* do a stop_rx here, start_rx is handled in uart_resume_port by call to setermios */
+ if (uart_console(uport) && !console_suspend_enabled)
+ uport->ops->stop_rx(uport);
+
/*
* This is done so we can hit the lowest possible state in suspend
* even with no_console_suspend
thanks,
--
js
suse labs
