From ab62a585a02af4dae2d615d4476e1bf493ff1be8 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Thu, 2 Jan 2014 22:49:27 +0100 Subject: [PATCH] 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 Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/cypress_m8.c | 63 +++++++++------------------------ 1 file changed, 16 insertions(+), 47 deletions(-) diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c index 07e003398613..763d1c59f8fc 100644 --- a/drivers/usb/serial/cypress_m8.c +++ b/drivers/usb/serial/cypress_m8.c @@ -113,7 +113,7 @@ struct cypress_private { 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 void cypress_set_termios(struct tty_struct *tty, 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 @@ static struct usb_serial_driver cypress_earthmate_device = { .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 @@ static struct usb_serial_driver cypress_hidcom_device = { .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 @@ static struct usb_serial_driver cypress_ca42v2_device = { .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 @@ static int cypress_tiocmset(struct tty_struct *tty, 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 @@ static void cypress_read_int_callback(struct urb *urb) 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 (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++; - if (priv->diff_status & UART_MSR_MASK) wake_up_interruptible(&port->port.delta_msr_wait); + } priv->prev_status = priv->current_status; } -- 2.20.1