USB: cypress_m8: switch to generic TIOCMIWAIT implementation
Switch to the generic TIOCMIWAIT implementation which does not suffer
from the races involved when using the deprecated sleep_on functions.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c
index 07e0033..763d1c5 100644
--- a/drivers/usb/serial/cypress_m8.c
+++ b/drivers/usb/serial/cypress_m8.c
@@ -113,7 +113,7 @@
int baud_rate; /* stores current baud rate in
integer form */
int isthrottled; /* if throttled, discard reads */
- char prev_status, diff_status; /* used for TIOCMIWAIT */
+ char prev_status; /* used for TIOCMIWAIT */
/* we pass a pointer to this as the argument sent to
cypress_set_termios old_termios */
struct ktermios tmp_termios; /* stores the old termios settings */
@@ -136,7 +136,6 @@
static int cypress_tiocmget(struct tty_struct *tty);
static int cypress_tiocmset(struct tty_struct *tty,
unsigned int set, unsigned int clear);
-static int cypress_tiocmiwait(struct tty_struct *tty, unsigned long arg);
static int cypress_chars_in_buffer(struct tty_struct *tty);
static void cypress_throttle(struct tty_struct *tty);
static void cypress_unthrottle(struct tty_struct *tty);
@@ -162,7 +161,7 @@
.set_termios = cypress_set_termios,
.tiocmget = cypress_tiocmget,
.tiocmset = cypress_tiocmset,
- .tiocmiwait = cypress_tiocmiwait,
+ .tiocmiwait = usb_serial_generic_tiocmiwait,
.chars_in_buffer = cypress_chars_in_buffer,
.throttle = cypress_throttle,
.unthrottle = cypress_unthrottle,
@@ -188,7 +187,7 @@
.set_termios = cypress_set_termios,
.tiocmget = cypress_tiocmget,
.tiocmset = cypress_tiocmset,
- .tiocmiwait = cypress_tiocmiwait,
+ .tiocmiwait = usb_serial_generic_tiocmiwait,
.chars_in_buffer = cypress_chars_in_buffer,
.throttle = cypress_throttle,
.unthrottle = cypress_unthrottle,
@@ -214,7 +213,7 @@
.set_termios = cypress_set_termios,
.tiocmget = cypress_tiocmget,
.tiocmset = cypress_tiocmset,
- .tiocmiwait = cypress_tiocmiwait,
+ .tiocmiwait = usb_serial_generic_tiocmiwait,
.chars_in_buffer = cypress_chars_in_buffer,
.throttle = cypress_throttle,
.unthrottle = cypress_unthrottle,
@@ -864,45 +863,6 @@
return cypress_write(tty, port, NULL, 0);
}
-
-static int cypress_tiocmiwait(struct tty_struct *tty, unsigned long arg)
-{
- struct usb_serial_port *port = tty->driver_data;
- struct cypress_private *priv = usb_get_serial_port_data(port);
- char diff;
-
- for (;;) {
- interruptible_sleep_on(&port->port.delta_msr_wait);
- /* see if a signal did it */
- if (signal_pending(current))
- return -ERESTARTSYS;
-
- if (port->serial->disconnected)
- return -EIO;
-
- diff = priv->diff_status;
- if (diff == 0)
- return -EIO; /* no change => error */
-
- /* consume all events */
- priv->diff_status = 0;
-
- /* return 0 if caller wanted to know about
- these bits */
- if (((arg & TIOCM_RNG) && (diff & UART_RI)) ||
- ((arg & TIOCM_DSR) && (diff & UART_DSR)) ||
- ((arg & TIOCM_CD) && (diff & UART_CD)) ||
- ((arg & TIOCM_CTS) && (diff & UART_CTS)))
- return 0;
- /* otherwise caller can't care less about what
- * happened, and so we continue to wait for
- * more events.
- */
- }
-
- return 0;
-}
-
static void cypress_set_termios(struct tty_struct *tty,
struct usb_serial_port *port, struct ktermios *old_termios)
{
@@ -1185,11 +1145,20 @@
spin_lock_irqsave(&priv->lock, flags);
/* check to see if status has changed */
if (priv->current_status != priv->prev_status) {
- priv->diff_status |= priv->current_status ^
- priv->prev_status;
+ u8 delta = priv->current_status ^ priv->prev_status;
- if (priv->diff_status & UART_MSR_MASK)
+ if (delta & UART_MSR_MASK) {
+ if (delta & UART_CTS)
+ port->icount.cts++;
+ if (delta & UART_DSR)
+ port->icount.dsr++;
+ if (delta & UART_RI)
+ port->icount.rng++;
+ if (delta & UART_CD)
+ port->icount.dcd++;
+
wake_up_interruptible(&port->port.delta_msr_wait);
+ }
priv->prev_status = priv->current_status;
}