USB: opticon: switch to generic read implementation
authorJohan Hovold <jhovold@gmail.com>
Sun, 18 Nov 2012 12:23:36 +0000 (13:23 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 21 Nov 2012 21:33:56 +0000 (13:33 -0800)
Switch to the more efficient generic read implementation.

Note that the generic implementation is not required to hold the tty
port mutex during resume due to the read-urb free mask and write start
flag.

Note also that the generic resume implementation will call generic
write start if there is a bulk-out end-point, but that nothing will be
submitted as the write fifo is not used and is empty.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/serial/opticon.c

index 8d6ece0..c6bfb83 100644 (file)
@@ -1,6 +1,7 @@
 /*
  * Opticon USB barcode to serial driver
  *
+ * Copyright (C) 2011 - 2012 Johan Hovold <jhovold@gmail.com>
  * Copyright (C) 2011 Martin Jansen <martin.jansen@opticon.com>
  * Copyright (C) 2008 - 2009 Greg Kroah-Hartman <gregkh@suse.de>
  * Copyright (C) 2008 - 2009 Novell Inc.
@@ -40,10 +41,7 @@ MODULE_DEVICE_TABLE(usb, id_table);
 
 /* This structure holds all of the individual device information */
 struct opticon_private {
-       struct urb *bulk_read_urb;
        spinlock_t lock;        /* protects the following flags */
-       bool throttled;
-       bool actually_throttled;
        bool rts;
        bool cts;
        int outstanding_urbs;
@@ -109,49 +107,6 @@ static void opticon_process_read_urb(struct urb *urb)
        }
 }
 
-static void opticon_read_bulk_callback(struct urb *urb)
-{
-       struct usb_serial_port *port = urb->context;
-       struct opticon_private *priv = usb_get_serial_port_data(port);
-       unsigned char *data = urb->transfer_buffer;
-       int status = urb->status;
-       int result;
-
-       switch (status) {
-       case 0:
-               /* success */
-               break;
-       case -ECONNRESET:
-       case -ENOENT:
-       case -ESHUTDOWN:
-               /* this urb is terminated, clean up */
-               dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
-                       __func__, status);
-               return;
-       default:
-               dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
-                       __func__, status);
-               goto exit;
-       }
-
-       usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
-
-       opticon_process_read_urb(urb);
-exit:
-       spin_lock(&priv->lock);
-
-       /* Continue trying to always read if we should */
-       if (!priv->throttled) {
-               result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC);
-               if (result)
-                       dev_err(&port->dev,
-                           "%s - failed resubmitting read urb, error %d\n",
-                                                       __func__, result);
-       } else
-               priv->actually_throttled = true;
-       spin_unlock(&priv->lock);
-}
-
 static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
                                u8 val)
 {
@@ -179,11 +134,9 @@ static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
        struct opticon_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;
-       int result = 0;
+       int res;
 
        spin_lock_irqsave(&priv->lock, flags);
-       priv->throttled = false;
-       priv->actually_throttled = false;
        priv->rts = false;
        spin_unlock_irqrestore(&priv->lock, flags);
 
@@ -191,25 +144,17 @@ static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port)
        send_control_msg(port, CONTROL_RTS, 0);
 
        /* clear the halt status of the enpoint */
-       usb_clear_halt(port->serial->dev, priv->bulk_read_urb->pipe);
+       usb_clear_halt(port->serial->dev, port->read_urb->pipe);
+
+       res = usb_serial_generic_open(tty, port);
+       if (!res)
+               return res;
 
-       result = usb_submit_urb(priv->bulk_read_urb, GFP_KERNEL);
-       if (result)
-               dev_err(&port->dev,
-                       "%s - failed resubmitting read urb, error %d\n",
-                       __func__, result);
        /* Request CTS line state, sometimes during opening the current
         * CTS state can be missed. */
        send_control_msg(port, RESEND_CTS_STATE, 1);
-       return result;
-}
 
-static void opticon_close(struct usb_serial_port *port)
-{
-       struct opticon_private *priv = usb_get_serial_port_data(port);
-
-       /* shutdown our urbs */
-       usb_kill_urb(priv->bulk_read_urb);
+       return res;
 }
 
 static void opticon_write_control_callback(struct urb *urb)
@@ -346,40 +291,6 @@ static int opticon_write_room(struct tty_struct *tty)
        return 2048;
 }
 
-static void opticon_throttle(struct tty_struct *tty)
-{
-       struct usb_serial_port *port = tty->driver_data;
-       struct opticon_private *priv = usb_get_serial_port_data(port);
-       unsigned long flags;
-
-       spin_lock_irqsave(&priv->lock, flags);
-       priv->throttled = true;
-       spin_unlock_irqrestore(&priv->lock, flags);
-}
-
-
-static void opticon_unthrottle(struct tty_struct *tty)
-{
-       struct usb_serial_port *port = tty->driver_data;
-       struct opticon_private *priv = usb_get_serial_port_data(port);
-       unsigned long flags;
-       int result, was_throttled;
-
-       spin_lock_irqsave(&priv->lock, flags);
-       priv->throttled = false;
-       was_throttled = priv->actually_throttled;
-       priv->actually_throttled = false;
-       spin_unlock_irqrestore(&priv->lock, flags);
-
-       if (was_throttled) {
-               result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC);
-               if (result)
-                       dev_err(&port->dev,
-                               "%s - failed submitting read urb, error %d\n",
-                                                       __func__, result);
-       }
-}
-
 static int opticon_tiocmget(struct tty_struct *tty)
 {
        struct usb_serial_port *port = tty->driver_data;
@@ -495,7 +406,6 @@ static int opticon_port_probe(struct usb_serial_port *port)
                return -ENOMEM;
 
        spin_lock_init(&priv->lock);
-       priv->bulk_read_urb = port->read_urbs[0];
 
        usb_set_serial_port_data(port, priv);
 
@@ -511,32 +421,6 @@ static int opticon_port_remove(struct usb_serial_port *port)
        return 0;
 }
 
-static int opticon_suspend(struct usb_serial *serial, pm_message_t message)
-{
-       struct opticon_private *priv;
-
-       priv = usb_get_serial_port_data(serial->port[0]);
-
-       usb_kill_urb(priv->bulk_read_urb);
-       return 0;
-}
-
-static int opticon_resume(struct usb_serial *serial)
-{
-       struct usb_serial_port *port = serial->port[0];
-       struct opticon_private *priv = usb_get_serial_port_data(port);
-       int result;
-
-       mutex_lock(&port->port.mutex);
-       /* This is protected by the port mutex against close/open */
-       if (test_bit(ASYNCB_INITIALIZED, &port->port.flags))
-               result = usb_submit_urb(priv->bulk_read_urb, GFP_NOIO);
-       else
-               result = 0;
-       mutex_unlock(&port->port.mutex);
-       return result;
-}
-
 static struct usb_serial_driver opticon_device = {
        .driver = {
                .owner =        THIS_MODULE,
@@ -549,17 +433,14 @@ static struct usb_serial_driver opticon_device = {
        .port_probe =           opticon_port_probe,
        .port_remove =          opticon_port_remove,
        .open =                 opticon_open,
-       .close =                opticon_close,
        .write =                opticon_write,
        .write_room =           opticon_write_room,
-       .throttle =             opticon_throttle,
-       .unthrottle =           opticon_unthrottle,
+       .throttle =             usb_serial_generic_throttle,
+       .unthrottle =           usb_serial_generic_unthrottle,
        .ioctl =                opticon_ioctl,
        .tiocmget =             opticon_tiocmget,
        .tiocmset =             opticon_tiocmset,
-       .suspend =              opticon_suspend,
-       .resume =               opticon_resume,
-       .read_bulk_callback =   opticon_read_bulk_callback,
+       .process_read_urb =     opticon_process_read_urb,
 };
 
 static struct usb_serial_driver * const serial_drivers[] = {