diff options
| author | Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com> | 2022-06-08 00:22:44 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-06-10 13:30:41 +0200 |
| commit | cfab87c2c2715763dc7e43d9968bdaa01cde4bc3 (patch) | |
| tree | ba9de1fdf2ace007227aad12aeec2c9003a94f8a /drivers/tty | |
| parent | e74024b2eccbb784824a0f9feaeaaa3b47514b79 (diff) | |
| download | lwn-cfab87c2c2715763dc7e43d9968bdaa01cde4bc3.tar.gz lwn-cfab87c2c2715763dc7e43d9968bdaa01cde4bc3.zip | |
serial: core: Introduce callback for start_rx and do stop_rx in suspend only if this callback implementation is present.
In suspend sequence there is a need to perform stop_rx during suspend
sequence to prevent any asynchronous data over rx line. However this
can cause problem to drivers which dont do re-start_rx during set_termios.
Add new callback start_rx and perform stop_rx only when implementation of
start_rx is present. Also add call to start_rx in resume sequence so that
drivers who come across this problem can make use of this framework.
Fixes: c9d2325cdb92 ("serial: core: Do stop_rx in suspend path for console if console_suspend is disabled")
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Link: https://lore.kernel.org/r/1654627965-1461-2-git-send-email-quic_vnivarth@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 9a85b41caa0a..338ebadfd44b 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -2214,11 +2214,12 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport) /* * Nothing to do if the console is not suspending * except stop_rx to prevent any asynchronous data - * over RX line. Re-start_rx, when required, is - * done by set_termios in resume sequence + * over RX line. However ensure that we will be + * able to Re-start_rx later. */ if (!console_suspend_enabled && uart_console(uport)) { - uport->ops->stop_rx(uport); + if (uport->ops->start_rx) + uport->ops->stop_rx(uport); goto unlock; } @@ -2310,6 +2311,8 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport) if (console_suspend_enabled) uart_change_pm(state, UART_PM_STATE_ON); uport->ops->set_termios(uport, &termios, NULL); + if (!console_suspend_enabled && uport->ops->start_rx) + uport->ops->start_rx(uport); if (console_suspend_enabled) console_start(uport->cons); } |