Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

tty: USB tty devices can block in tcdrain when unplugged

Browse source 
The underlying problem is that the device methods don't all correctly
handle disconnected status and some keep reporting bytes pending which
causes tcdrain to stall.

When the cable is unplugged they are definitely gone, and as this is true
for all USB cables we can fix it in the core usb serial code.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alan Cox 2009-01-02 13:47:06 +00:00 committed by Linus Torvalds
parent 39aced68d6
commit eff6937a46
1 changed files with 4 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
drivers/usb/serial/usb-serial.c
View file

@ -339,6 +339,10 @@ static int serial_chars_in_buffer(struct tty_struct *tty)
dbg("%s = port %d", __func__, port->number);
WARN_ON(!port->port.count);
/* if the device was unplugged then any remaining characters
fell out of the connector ;) */
if (port->serial->disconnected)
return 0;
/* pass on to the driver specific version of this function */
return port->serial->type->chars_in_buffer(tty);
}