[PATCH] USB: add ability for usb-serial drivers to determine if their write urb is currently being used.
This removes a lot of racy and buggy code by trying to check the status of the urb.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/cyberjack.c b/drivers/usb/serial/cyberjack.c
index 46a204c..b5b4310 100644
--- a/drivers/usb/serial/cyberjack.c
+++ b/drivers/usb/serial/cyberjack.c
@@ -213,10 +213,14 @@
return (0);
}
- if (port->write_urb->status == -EINPROGRESS) {
+ spin_lock(&port->lock);
+ if (port->write_urb_busy) {
+ spin_unlock(&port->lock);
dbg("%s - already writing", __FUNCTION__);
- return (0);
+ return 0;
}
+ port->write_urb_busy = 1;
+ spin_unlock(&port->lock);
spin_lock_irqsave(&priv->lock, flags);
@@ -224,6 +228,7 @@
/* To much data for buffer. Reset buffer. */
priv->wrfilled=0;
spin_unlock_irqrestore(&priv->lock, flags);
+ port->write_urb_busy = 0;
return (0);
}
@@ -268,6 +273,7 @@
priv->wrfilled=0;
priv->wrsent=0;
spin_unlock_irqrestore(&priv->lock, flags);
+ port->write_urb_busy = 0;
return 0;
}
@@ -412,7 +418,8 @@
struct cyberjack_private *priv = usb_get_serial_port_data(port);
dbg("%s - port %d", __FUNCTION__, port->number);
-
+
+ port->write_urb_busy = 0;
if (urb->status) {
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
return;
@@ -424,12 +431,6 @@
if( priv->wrfilled ) {
int length, blksize, result;
- if (port->write_urb->status == -EINPROGRESS) {
- dbg("%s - already writing", __FUNCTION__);
- spin_unlock(&priv->lock);
- return;
- }
-
dbg("%s - transmitting data (frame n)", __FUNCTION__);
length = ((priv->wrfilled - priv->wrsent) > port->bulk_out_size) ?