1 files changed, 19 insertions, 172 deletions

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 6e437f9e4b9b..a41974e17687 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1,6 +1,8 @@
 /*
  * USB FTDI SIO driver
  *
+ *      Copyright (C) 2009 - 2010
+ *          Johan Hovold (jhovold@gmail.com)
  *      Copyright (C) 1999 - 2001
  *          Greg Kroah-Hartman (greg@kroah.com)
  *          Bill Ryder (bryder@sgi.com)
@@ -49,8 +51,8 @@
 /*
  * Version Information
  */
-#define DRIVER_VERSION "v1.5.0"
-#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Bill Ryder <bryder@sgi.com>, Kuba Ober <kuba@mareimbrium.org>, Andreas Mohr"
+#define DRIVER_VERSION "v1.6.0"
+#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Bill Ryder <bryder@sgi.com>, Kuba Ober <kuba@mareimbrium.org>, Andreas Mohr, Johan Hovold <jhovold@gmail.com>"
 #define DRIVER_DESC "USB FTDI Serial Converters Driver"
 
 static int debug;
@@ -87,9 +89,6 @@ struct ftdi_private {
                                    be enabled */
 
         unsigned int latency;           /* latency setting in use */
-        spinlock_t tx_lock;     /* spinlock for transmit state */
-        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() and change_speed() */
 };
@@ -784,12 +783,9 @@ static int  ftdi_sio_port_remove(struct usb_serial_port *port);
 static int  ftdi_open(struct tty_struct *tty, struct usb_serial_port *port);
 static void ftdi_close(struct usb_serial_port *port);
 static void ftdi_dtr_rts(struct usb_serial_port *port, int on);
-static int  ftdi_write(struct tty_struct *tty, struct usb_serial_port *port,
-                        const unsigned char *buf, int count);
-static int  ftdi_write_room(struct tty_struct *tty);
-static int  ftdi_chars_in_buffer(struct tty_struct *tty);
-static void ftdi_write_bulk_callback(struct urb *urb);
 static void ftdi_process_read_urb(struct urb *urb);
+static int ftdi_prepare_write_buffer(struct usb_serial_port *port,
+                void **dest, size_t size, const void *buf, size_t count);
 static void ftdi_set_termios(struct tty_struct *tty,
                         struct usb_serial_port *port, struct ktermios *old);
 static int  ftdi_tiocmget(struct tty_struct *tty, struct file *file);
@@ -816,6 +812,8 @@ static struct usb_serial_driver ftdi_sio_device = {
         .id_table =             id_table_combined,
         .num_ports =            1,
         .bulk_in_size =         512,
+        /* Must modify prepare_write_buffer if multi_urb_write is changed. */
+        .multi_urb_write =      1,
         .probe =                ftdi_sio_probe,
         .port_probe =           ftdi_sio_port_probe,
         .port_remove =          ftdi_sio_port_remove,
@@ -824,11 +822,8 @@ static struct usb_serial_driver ftdi_sio_device = {
         .dtr_rts =              ftdi_dtr_rts,
         .throttle =             usb_serial_generic_throttle,
         .unthrottle =           usb_serial_generic_unthrottle,
-        .write =                ftdi_write,
-        .write_room =           ftdi_write_room,
-        .chars_in_buffer =      ftdi_chars_in_buffer,
         .process_read_urb =     ftdi_process_read_urb,
-        .write_bulk_callback =  ftdi_write_bulk_callback,
+        .prepare_write_buffer = ftdi_prepare_write_buffer,
         .tiocmget =             ftdi_tiocmget,
         .tiocmset =             ftdi_tiocmset,
         .ioctl =                ftdi_ioctl,
@@ -844,9 +839,6 @@ static struct usb_serial_driver ftdi_sio_device = {
 #define HIGH 1
 #define LOW 0
 
-/* number of outstanding urbs to prevent userspace DoS from happening */
-#define URB_UPPER_LIMIT 42
-
 /*
  * ***************************************************************************
  * Utility functions
@@ -1536,7 +1528,6 @@ static int ftdi_sio_port_probe(struct usb_serial_port *port)
         }
 
         kref_init(&priv->kref);
-        spin_lock_init(&priv->tx_lock);
         mutex_init(&priv->cfg_lock);
         init_waitqueue_head(&priv->delta_msr_wait);
 
@@ -1761,31 +1752,15 @@ static void ftdi_close(struct usb_serial_port *port)
  *
  * The new devices do not require this byte
  */
-static int ftdi_write(struct tty_struct *tty, struct usb_serial_port *port,
-                           const unsigned char *buf, int count)
+static int ftdi_prepare_write_buffer(struct usb_serial_port *port,
+                void **dest, size_t size, const void *src, size_t count)
 {
-        struct ftdi_private *priv = usb_get_serial_port_data(port);
-        struct urb *urb;
+        struct ftdi_private *priv;
         unsigned char *buffer;
         int data_offset ;       /* will be 1 for the SIO and 0 otherwise */
-        int status;
         int transfer_size;
-        unsigned long flags;
-
-        dbg("%s port %d, %d bytes", __func__, port->number, count);
 
-        if (count == 0) {
-                dbg("write request of 0 bytes");
-                return 0;
-        }
-        spin_lock_irqsave(&priv->tx_lock, flags);
-        if (priv->tx_outstanding_urbs > URB_UPPER_LIMIT) {
-                spin_unlock_irqrestore(&priv->tx_lock, flags);
-                dbg("%s - write limit hit", __func__);
-                return 0;
-        }
-        priv->tx_outstanding_urbs++;
-        spin_unlock_irqrestore(&priv->tx_lock, flags);
+        priv = usb_get_serial_port_data(port);
 
         data_offset = priv->write_offset;
         dbg("data_offset set to %d", data_offset);
@@ -1801,17 +1776,9 @@ static int ftdi_write(struct tty_struct *tty, struct usb_serial_port *port,
 
         buffer = kmalloc(transfer_size, GFP_ATOMIC);
         if (!buffer) {
-                dev_err(&port->dev,
-                        "%s ran out of kernel memory for urb ...\n", __func__);
-                count = -ENOMEM;
-                goto error_no_buffer;
-        }
-
-        urb = usb_alloc_urb(0, GFP_ATOMIC);
-        if (!urb) {
-                dev_err(&port->dev, "%s - no more free urbs\n", __func__);
-                count = -ENOMEM;
-                goto error_no_urb;
+                dev_err(&port->dev, "%s - could not allocate buffer\n",
+                                __func__);
+                return -ENOMEM;
         }
 
         /* Copy data */
@@ -1821,7 +1788,7 @@ static int ftdi_write(struct tty_struct *tty, struct usb_serial_port *port,
                 int user_pktsz = priv->max_packet_size - data_offset;
                 int todo = count;
                 unsigned char *first_byte = buffer;
-                const unsigned char *current_position = buf;
+                const unsigned char *current_position = src;
 
                 while (todo > 0) {
                         if (user_pktsz > todo)
@@ -1836,134 +1803,14 @@ static int ftdi_write(struct tty_struct *tty, struct usb_serial_port *port,
                         todo -= user_pktsz;
                 }
         } else {
-                /* No control byte required. */
-                /* Copy in the data to send */
-                memcpy(buffer, buf, count);
+                memcpy(buffer, src, count);
         }
 
-        usb_serial_debug_data(debug, &port->dev, __func__,
-                                                transfer_size, buffer);
-
-        /* fill the buffer and send it */
-        usb_fill_bulk_urb(urb, port->serial->dev,
-                        usb_sndbulkpipe(port->serial->dev,
-                                        port->bulk_out_endpointAddress),
-                        buffer, transfer_size,
-                        ftdi_write_bulk_callback, port);
-
-        status = usb_submit_urb(urb, GFP_ATOMIC);
-        if (status) {
-                dev_err(&port->dev,
-                        "%s - failed submitting write urb, error %d\n",
-                        __func__, status);
-                count = status;
-                goto error;
-        } else {
-                spin_lock_irqsave(&priv->tx_lock, flags);
-                priv->tx_outstanding_bytes += count;
-                spin_unlock_irqrestore(&priv->tx_lock, flags);
-        }
+        *dest = buffer;
 
-        /* we are done with this urb, so let the host driver
-         * really free it when it is finished with it */
-        usb_free_urb(urb);
-
-        dbg("%s write returning: %d", __func__, count);
-        return count;
-error:
-        usb_free_urb(urb);
-error_no_urb:
-        kfree(buffer);
-error_no_buffer:
-        spin_lock_irqsave(&priv->tx_lock, flags);
-        priv->tx_outstanding_urbs--;
-        spin_unlock_irqrestore(&priv->tx_lock, flags);
         return count;
 }
 
-/* This function may get called when the device is closed */
-static void ftdi_write_bulk_callback(struct urb *urb)
-{
-        unsigned long flags;
-        struct usb_serial_port *port = urb->context;
-        struct ftdi_private *priv;
-        int data_offset;       /* will be 1 for the SIO and 0 otherwise */
-        unsigned long countback;
-        int status = urb->status;
-
-        /* free up the transfer buffer, as usb_free_urb() does not do this */
-        kfree(urb->transfer_buffer);
-
-        dbg("%s - port %d", __func__, port->number);
-
-        priv = usb_get_serial_port_data(port);
-        if (!priv) {
-                dbg("%s - bad port private data pointer - exiting", __func__);
-                return;
-        }
-        /* account for transferred data */
-        countback = urb->transfer_buffer_length;
-        data_offset = priv->write_offset;
-        if (data_offset > 0) {
-                /* Subtract the control bytes */
-                countback -= (data_offset * DIV_ROUND_UP(countback, priv->max_packet_size));
-        }
-        spin_lock_irqsave(&priv->tx_lock, flags);
-        --priv->tx_outstanding_urbs;
-        priv->tx_outstanding_bytes -= countback;
-        spin_unlock_irqrestore(&priv->tx_lock, flags);
-
-        if (status) {
-                dbg("nonzero write bulk status received: %d", status);
-        }
-
-        usb_serial_port_softint(port);
-}
-
-static int ftdi_write_room(struct tty_struct *tty)
-{
-        struct usb_serial_port *port = tty->driver_data;
-        struct ftdi_private *priv = usb_get_serial_port_data(port);
-        int room;
-        unsigned long flags;
-
-        dbg("%s - port %d", __func__, port->number);
-
-        spin_lock_irqsave(&priv->tx_lock, flags);
-        if (priv->tx_outstanding_urbs < URB_UPPER_LIMIT) {
-                /*
-                 * We really can take anything the user throws at us
-                 * but let's pick a nice big number to tell the tty
-                 * layer that we have lots of free space
-                 */
-                room = 2048;
-        } else {
-                room = 0;
-        }
-        spin_unlock_irqrestore(&priv->tx_lock, flags);
-        return room;
-}
-
-static int ftdi_chars_in_buffer(struct tty_struct *tty)
-{
-        struct usb_serial_port *port = tty->driver_data;
-        struct ftdi_private *priv = usb_get_serial_port_data(port);
-        int buffered;
-        unsigned long flags;
-
-        dbg("%s - port %d", __func__, port->number);
-
-        spin_lock_irqsave(&priv->tx_lock, flags);
-        buffered = (int)priv->tx_outstanding_bytes;
-        spin_unlock_irqrestore(&priv->tx_lock, flags);
-        if (buffered < 0) {
-                dev_err(&port->dev, "%s outstanding tx bytes is negative!\n",
-                        __func__);
-                buffered = 0;
-        }
-        return buffered;
-}
-
 static int ftdi_process_packet(struct tty_struct *tty,
                 struct usb_serial_port *port, struct ftdi_private *priv,
                 char *packet, int len)