Oliver Neukum writes:
>
> Am Donnerstag, 29. Juli 2010, 17:05:41 schrieb Bill Pemberton:
> > +static int ssu100_ioctl(struct tty_struct *tty, struct file *file,
> > + unsigned int cmd, unsigned long arg)
> > +{
> > + struct usb_serial_port *port = tty->driver_data;
> > + struct ssu100_port_private *priv = usb_get_serial_port_data(port);
> > +
> > + dbg("%s cmd 0x%04x", __func__, cmd);
> > +
> > + switch (cmd) {
> > + case TIOCGSERIAL:
> > + return get_serial_info(port,
> > + (struct serial_struct __user *) arg);
> > +
> > + case TIOCMIWAIT:
> > + while (priv != NULL) {
> > + u8 prevMSR = priv->shadowMSR & SERIAL_MSR_MASK;
> > + interruptible_sleep_on(&priv->delta_msr_wait);
>
> This won't fly
>
> 1. you have no guarantee that the packet that would wake you up hasn't arrived
> by the time you go to sleep. Use a proper wait_event_ macro
> 2. you need to handle disconnection
>
Ok, I'll work on it.
The TIOCMIWAIT logic is pretty much the same as most of the other
usb-serial devices and do not use wait_event_. Is there something in
my implementation that I've missed or do all of these drivers need to
be fixed in the same way?
--
Bill
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