On Tue, Jun 11, 2024 at 08:23:11PM +0300, Dmitry Smirnov wrote: > This patch addresses a kernel hang issue with the mos7840 driver when > PC resuming from a suspend with a device connected to the serial port. > > This patch introduces two new functions: mos7840_suspend() and mos7840_resume(). > > Tested with Delock 87414 USB 2.0 to 4x serial adapter. > > Signed-off-by: Dmitry Smirnov <d.smirnov@xxxxxxxx> > --- > V3: Addressed review comments from previous submits > > drivers/usb/serial/mos7840.c | 51 ++++++++++++++++++++++++++++++++++++ > 1 file changed, 51 insertions(+) > > diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c > index 8b0308d84270..3e5f761f4925 100644 > --- a/drivers/usb/serial/mos7840.c > +++ b/drivers/usb/serial/mos7840.c > @@ -1737,6 +1737,55 @@ static void mos7840_port_remove(struct usb_serial_port *port) > kfree(mos7840_port); > } > > +static int mos7840_suspend(struct usb_serial *serial, pm_message_t message) > +{ > + struct moschip_port *mos7840_port; > + struct usb_serial_port *port; > + int i; > + > + dev_dbg(&serial->interface->dev, "mos7840_suspend\n"); ftrace is your friend, there is no need for debug lines like this anymore. > + > + for (i = 0; i < serial->num_ports; ++i) { > + port = serial->port[i]; > + if (!tty_port_initialized(&port->port)) > + continue; > + > + mos7840_port = usb_get_serial_port_data(port); > + > + usb_kill_urb(mos7840_port->read_urb); > + mos7840_port->read_urb_busy = false; > + } > + return 0; > +} > + > +static int mos7840_resume(struct usb_serial *serial) > +{ > + struct moschip_port *mos7840_port; > + struct usb_serial_port *port; > + int res; > + int i; > + > + dev_dbg(&serial->interface->dev, "mos7840_resume\n"); Same here, not needed. thanks, greg k-h