diff options
| author | Alessio Igor Bogani <abogani@texware.it> | 2010-03-13 18:35:14 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-03-19 07:24:21 -0700 |
| commit | 9c67d28e4e7683b4f667fa4c7b6f9aee92b44b5c (patch) | |
| tree | 3ebe03430385bbcab1ecaa8f53cc0037386fa44e | |
| parent | 11b10d999469dc0514447a15e88c7ef14ec0761d (diff) | |
| download | linux-9c67d28e4e7683b4f667fa4c7b6f9aee92b44b5c.tar.bz2 | |
USB: ftdi_sio: Fix locking for change_speed() function
The change_speed() function should be serialized against multiple calls.
Use the cfg_lock mutex to do this.
Signed-off-by: Alessio Igor Bogani <abogani@texware.it>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/usb/serial/ftdi_sio.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c index 6fc09dc3b53e..1d7c4fac02e8 100644 --- a/drivers/usb/serial/ftdi_sio.c +++ b/drivers/usb/serial/ftdi_sio.c @@ -91,7 +91,7 @@ struct ftdi_private { unsigned long tx_outstanding_bytes; unsigned long tx_outstanding_urbs; unsigned short max_packet_size; - struct mutex cfg_lock; /* Avoid mess by parallel calls of config ioctl() */ + struct mutex cfg_lock; /* Avoid mess by parallel calls of config ioctl() and change_speed() */ }; /* struct ftdi_sio_quirk is used by devices requiring special attention. */ @@ -1273,8 +1273,8 @@ check_and_exit: (priv->flags & ASYNC_SPD_MASK)) || (((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) && (old_priv.custom_divisor != priv->custom_divisor))) { - mutex_unlock(&priv->cfg_lock); change_speed(tty, port); + mutex_unlock(&priv->cfg_lock); } else mutex_unlock(&priv->cfg_lock); @@ -2265,9 +2265,11 @@ static void ftdi_set_termios(struct tty_struct *tty, clear_mctrl(port, TIOCM_DTR | TIOCM_RTS); } else { /* set the baudrate determined before */ + mutex_lock(&priv->cfg_lock); if (change_speed(tty, port)) dev_err(&port->dev, "%s urb failed to set baudrate\n", __func__); + mutex_unlock(&priv->cfg_lock); /* Ensure RTS and DTR are raised when baudrate changed from 0 */ if (!old_termios || (old_termios->c_cflag & CBAUD) == B0) set_mctrl(port, TIOCM_DTR | TIOCM_RTS); |