From 83a3dfc018943b05b6daf3a6f891833e1aabfa1f Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 23 Jun 2026 17:08:15 +0200 Subject: [PATCH] USB: serial: digi_acceleport: fix broken rx after throttle If the port is closed while throttled, the read urb is never resubmitted and the port will not receive any further data until the device is reconnected (or the driver is rebound). Clear the throttle flags and submit the urb if needed when opening the port. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Johan Hovold --- drivers/usb/serial/digi_acceleport.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/usb/serial/digi_acceleport.c b/drivers/usb/serial/digi_acceleport.c index fa5c3539f806..dea039163661 100644 --- a/drivers/usb/serial/digi_acceleport.c +++ b/drivers/usb/serial/digi_acceleport.c @@ -1076,6 +1076,7 @@ static int digi_open(struct tty_struct *tty, struct usb_serial_port *port) unsigned char buf[32]; struct digi_port *priv = usb_get_serial_port_data(port); struct ktermios not_termios; + int throttled; /* be sure the device is started up */ if (digi_startup_device(port->serial) != 0) @@ -1103,6 +1104,21 @@ static int digi_open(struct tty_struct *tty, struct usb_serial_port *port) not_termios.c_iflag = ~tty->termios.c_iflag; digi_set_termios(tty, port, ¬_termios); } + + spin_lock_irq(&priv->dp_port_lock); + throttled = priv->dp_throttle_restart; + priv->dp_throttled = 0; + priv->dp_throttle_restart = 0; + spin_unlock_irq(&priv->dp_port_lock); + + if (throttled) { + ret = usb_submit_urb(port->read_urb, GFP_KERNEL); + if (ret) { + dev_err(&port->dev, "failed to submit read urb: %d\n", ret); + return ret; + } + } + return 0; }