4 files changed, 48 insertions, 176 deletions

diff --git a/drivers/usb/serial/aircable.c b/drivers/usb/serial/aircable.c
index cac5162937b3..8a990a763c21 100644
--- a/drivers/usb/serial/aircable.c
+++ b/drivers/usb/serial/aircable.c
@@ -84,9 +84,10 @@ static const struct usb_device_id id_table[] = {
 MODULE_DEVICE_TABLE(usb, id_table);
 
 static int aircable_prepare_write_buffer(struct usb_serial_port *port,
-                void **dest, size_t size, const void *src, size_t count)
+                                                void *dest, size_t size)
 {
-        unsigned char *buf = *dest;
+        int count;
+        unsigned char *buf = dest;
 
         count = kfifo_out_locked(&port->write_fifo, buf + HCI_HEADER_LENGTH,
                                         size - HCI_HEADER_LENGTH, &port->lock);
@@ -185,8 +186,6 @@ static struct usb_serial_driver aircable_device = {
         .id_table =             id_table,
         .num_ports =            1,
         .bulk_out_size =        HCI_COMPLETE_FRAME,
-        /* Must modify prepare_write_buffer if multi_urb_write is changed. */
-        .multi_urb_write =      0,
         .probe =                aircable_probe,
         .process_read_urb =     aircable_process_read_urb,
         .prepare_write_buffer = aircable_prepare_write_buffer,
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index f515f32cde68..14f7a34d614c 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -781,7 +781,7 @@ static void ftdi_close(struct usb_serial_port *port);
 static void ftdi_dtr_rts(struct usb_serial_port *port, int on);
 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);
+                                                void *dest, size_t size);
 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);
@@ -808,8 +808,7 @@ 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,
+        .bulk_out_size =        256,
         .probe =                ftdi_sio_probe,
         .port_probe =           ftdi_sio_port_probe,
         .port_remove =          ftdi_sio_port_remove,
@@ -1531,15 +1530,6 @@ static int ftdi_sio_port_probe(struct usb_serial_port *port)
                 quirk->port_probe(priv);
 
         priv->port = port;
-
-        /* Free port's existing write urb and transfer buffer. */
-        if (port->write_urb) {
-                usb_free_urb(port->write_urb);
-                port->write_urb = NULL;
-        }
-        kfree(port->bulk_out_buffer);
-        port->bulk_out_buffer = NULL;
-
         usb_set_serial_port_data(port, priv);
 
         ftdi_determine_type(port);
@@ -1734,8 +1724,7 @@ static void ftdi_close(struct usb_serial_port *port)
 
         dbg("%s", __func__);
 
-        /* shutdown our bulk read */
-        usb_kill_urb(port->read_urb);
+        usb_serial_generic_close(port);
         kref_put(&priv->kref, ftdi_sio_priv_release);
 }
 
@@ -1747,40 +1736,34 @@ static void ftdi_close(struct usb_serial_port *port)
  * The new devices do not require this byte
  */
 static int ftdi_prepare_write_buffer(struct usb_serial_port *port,
-                void **dest, size_t size, const void *src, size_t count)
+                                                void *dest, size_t size)
 {
         struct ftdi_private *priv;
-        unsigned char *buffer;
-        int len;
+        int count;
+        unsigned long flags;
 
         priv = usb_get_serial_port_data(port);
 
-        len = count;
-        if (priv->chip_type == SIO && count != 0)
-                len += ((count - 1) / (priv->max_packet_size - 1)) + 1;
-
-        buffer = kmalloc(len, GFP_ATOMIC);
-        if (!buffer) {
-                dev_err(&port->dev, "%s - could not allocate buffer\n",
-                                __func__);
-                return -ENOMEM;
-        }
-
         if (priv->chip_type == SIO) {
-                int i, msg_len;
-
-                for (i = 0; i < len; i += priv->max_packet_size) {
-                        msg_len = min_t(int, len - i, priv->max_packet_size) - 1;
-                        buffer[i] = (msg_len << 2) + 1;
-                        memcpy(&buffer[i + 1], src, msg_len);
-                        src += msg_len;
+                unsigned char *buffer = dest;
+                int i, len, c;
+
+                count = 0;
+                spin_lock_irqsave(&port->lock, flags);
+                for (i = 0; i < size - 1; i += priv->max_packet_size) {
+                        len = min_t(int, size - i, priv->max_packet_size) - 1;
+                        buffer[i] = (len << 2) + 1;
+                        c = kfifo_out(&port->write_fifo, &buffer[i + 1], len);
+                        if (!c)
+                                break;
+                        count += c + 1;
                 }
+                spin_unlock_irqrestore(&port->lock, flags);
         } else {
-                memcpy(buffer, src, count);
+                count = kfifo_out_locked(&port->write_fifo, dest, size,
+                                                                &port->lock);
         }
 
-        *dest = buffer;
-
         return count;
 }
 
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c
index 3ae17840175c..fcd30b841559 100644
--- a/drivers/usb/serial/generic.c
+++ b/drivers/usb/serial/generic.c
@@ -26,8 +26,6 @@
 
 static int debug;
 
-#define MAX_TX_URBS             40
-
 #ifdef CONFIG_USB_SERIAL_GENERIC
 
 static int generic_probe(struct usb_interface *interface,
@@ -172,90 +170,9 @@ void usb_serial_generic_close(struct usb_serial_port *port)
 EXPORT_SYMBOL_GPL(usb_serial_generic_close);
 
 int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
-                void **dest, size_t size, const void *src, size_t count)
+                                                void *dest, size_t size)
 {
-        if (!*dest) {
-                size = count;
-                *dest = kmalloc(count, GFP_ATOMIC);
-                if (!*dest) {
-                        dev_err(&port->dev, "%s - could not allocate buffer\n",
-                                        __func__);
-                        return -ENOMEM;
-                }
-        }
-        if (src) {
-                count = size;
-                memcpy(*dest, src, size);
-        } else {
-                count = kfifo_out_locked(&port->write_fifo, *dest, size,
-                                                                &port->lock);
-        }
-        return count;
-}
-EXPORT_SYMBOL_GPL(usb_serial_generic_prepare_write_buffer);
-
-static int usb_serial_multi_urb_write(struct tty_struct *tty,
-        struct usb_serial_port *port, const unsigned char *buf, int count)
-{
-        unsigned long flags;
-        struct urb *urb;
-        void *buffer;
-        int status;
-
-        spin_lock_irqsave(&port->lock, flags);
-        if (port->tx_urbs == MAX_TX_URBS) {
-                spin_unlock_irqrestore(&port->lock, flags);
-                dbg("%s - write limit hit", __func__);
-                return 0;
-        }
-        port->tx_urbs++;
-        spin_unlock_irqrestore(&port->lock, flags);
-
-        urb = usb_alloc_urb(0, GFP_ATOMIC);
-        if (!urb) {
-                dev_err(&port->dev, "%s - no free urbs available\n", __func__);
-                status = -ENOMEM;
-                goto err_urb;
-        }
-
-        buffer = NULL;
-        count = min_t(int, count, PAGE_SIZE);
-        count = port->serial->type->prepare_write_buffer(port, &buffer, 0,
-                                                                buf, count);
-        if (count < 0) {
-                status = count;
-                goto err_buf;
-        }
-        usb_serial_debug_data(debug, &port->dev, __func__, count, buffer);
-        usb_fill_bulk_urb(urb, port->serial->dev,
-                        usb_sndbulkpipe(port->serial->dev,
-                                        port->bulk_out_endpointAddress),
-                        buffer, count,
-                        port->serial->type->write_bulk_callback, port);
-
-        status = usb_submit_urb(urb, GFP_ATOMIC);
-        if (status) {
-                dev_err(&port->dev, "%s - error submitting urb: %d\n",
-                                __func__, status);
-                goto err;
-        }
-        spin_lock_irqsave(&port->lock, flags);
-        port->tx_bytes += urb->transfer_buffer_length;
-        spin_unlock_irqrestore(&port->lock, flags);
-
-        usb_free_urb(urb);
-
-        return count;
-err:
-        kfree(buffer);
-err_buf:
-        usb_free_urb(urb);
-err_urb:
-        spin_lock_irqsave(&port->lock, flags);
-        port->tx_urbs--;
-        spin_unlock_irqrestore(&port->lock, flags);
-
-        return status;
+        return kfifo_out_locked(&port->write_fifo, dest, size, &port->lock);
 }
 
 /**
@@ -286,8 +203,8 @@ retry:
 
         urb = port->write_urbs[i];
         count = port->serial->type->prepare_write_buffer(port,
-                                                &urb->transfer_buffer,
-                                                port->bulk_out_size, NULL, 0);
+                                                urb->transfer_buffer,
+                                                port->bulk_out_size);
         urb->transfer_buffer_length = count;
         usb_serial_debug_data(debug, &port->dev, __func__, count,
                                                 urb->transfer_buffer);
@@ -328,7 +245,6 @@ retry:
 int usb_serial_generic_write(struct tty_struct *tty,
         struct usb_serial_port *port, const unsigned char *buf, int count)
 {
-        struct usb_serial *serial = port->serial;
         int result;
 
         dbg("%s - port %d", __func__, port->number);
@@ -340,23 +256,18 @@ int usb_serial_generic_write(struct tty_struct *tty,
         if (!count)
                 return 0;
 
-        if (serial->type->multi_urb_write)
-                return usb_serial_multi_urb_write(tty, port, buf, count);
-
         count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
         result = usb_serial_generic_write_start(port);
+        if (result)
+                return result;
 
-        if (result >= 0)
-                result = count;
-
-        return result;
+        return count;
 }
 EXPORT_SYMBOL_GPL(usb_serial_generic_write);
 
 int usb_serial_generic_write_room(struct tty_struct *tty)
 {
         struct usb_serial_port *port = tty->driver_data;
-        struct usb_serial *serial = port->serial;
         unsigned long flags;
         int room;
 
@@ -366,10 +277,7 @@ int usb_serial_generic_write_room(struct tty_struct *tty)
                 return 0;
 
         spin_lock_irqsave(&port->lock, flags);
-        if (serial->type->multi_urb_write)
-                room = (MAX_TX_URBS - port->tx_urbs) * PAGE_SIZE;
-        else
-                room = kfifo_avail(&port->write_fifo);
+        room = kfifo_avail(&port->write_fifo);
         spin_unlock_irqrestore(&port->lock, flags);
 
         dbg("%s - returns %d", __func__, room);
@@ -379,7 +287,6 @@ int usb_serial_generic_write_room(struct tty_struct *tty)
 int usb_serial_generic_chars_in_buffer(struct tty_struct *tty)
 {
         struct usb_serial_port *port = tty->driver_data;
-        struct usb_serial *serial = port->serial;
         unsigned long flags;
         int chars;
 
@@ -389,10 +296,7 @@ int usb_serial_generic_chars_in_buffer(struct tty_struct *tty)
                 return 0;
 
         spin_lock_irqsave(&port->lock, flags);
-        if (serial->type->multi_urb_write)
-                chars = port->tx_bytes;
-        else
-                chars = kfifo_len(&port->write_fifo) + port->tx_bytes;
+        chars = kfifo_len(&port->write_fifo) + port->tx_bytes;
         spin_unlock_irqrestore(&port->lock, flags);
 
         dbg("%s - returns %d", __func__, chars);
@@ -479,35 +383,25 @@ void usb_serial_generic_write_bulk_callback(struct urb *urb)
 
         dbg("%s - port %d", __func__, port->number);
 
-        if (port->serial->type->multi_urb_write) {
-                kfree(urb->transfer_buffer);
+        for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
+                if (port->write_urbs[i] == urb)
+                        break;
 
-                spin_lock_irqsave(&port->lock, flags);
-                port->tx_bytes -= urb->transfer_buffer_length;
-                port->tx_urbs--;
-                spin_unlock_irqrestore(&port->lock, flags);
-        } else {
-                for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
-                        if (port->write_urbs[i] == urb)
-                                break;
+        spin_lock_irqsave(&port->lock, flags);
+        port->tx_bytes -= urb->transfer_buffer_length;
+        set_bit(i, &port->write_urbs_free);
+        spin_unlock_irqrestore(&port->lock, flags);
+
+        if (status) {
+                dbg("%s - non-zero urb status: %d", __func__, status);
 
                 spin_lock_irqsave(&port->lock, flags);
-                port->tx_bytes -= urb->transfer_buffer_length;
-                set_bit(i, &port->write_urbs_free);
+                kfifo_reset_out(&port->write_fifo);
                 spin_unlock_irqrestore(&port->lock, flags);
-
-                if (status) {
-                        spin_lock_irqsave(&port->lock, flags);
-                        kfifo_reset_out(&port->write_fifo);
-                        spin_unlock_irqrestore(&port->lock, flags);
-                } else {
-                        usb_serial_generic_write_start(port);
-                }
+        } else {
+                usb_serial_generic_write_start(port);
         }
 
-        if (status)
-                dbg("%s - non-zero urb status: %d", __func__, status);
-
         usb_serial_port_softint(port);
 }
 EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h
index 70b6d6b28997..061c997ae0cf 100644
--- a/include/linux/usb/serial.h
+++ b/include/linux/usb/serial.h
@@ -67,7 +67,6 @@ enum port_dev_state {
  * @write_urbs: pointers to the bulk out urbs for this port
  * @write_urbs_free: status bitmap the for bulk out urbs
  * @tx_bytes: number of bytes currently in host stack queues
- * @tx_urbs: number of urbs currently in host stack queues
  * @bulk_out_endpointAddress: endpoint address for the bulk out pipe for this
  *      port.
  * @flags: usb serial port flags
@@ -112,7 +111,6 @@ struct usb_serial_port {
         __u8                    bulk_out_endpointAddress;
 
         int                     tx_bytes;
-        int                     tx_urbs;
 
         unsigned long           flags;
         wait_queue_head_t       write_wait;
@@ -238,8 +236,6 @@ struct usb_serial_driver {
         struct usb_driver       *usb_driver;
         struct usb_dynids       dynids;
 
-        unsigned char           multi_urb_write:1;
-
         size_t                  bulk_in_size;
         size_t                  bulk_out_size;
 
@@ -291,7 +287,7 @@ struct usb_serial_driver {
         void (*process_read_urb)(struct urb *urb);
         /* Called by the generic write implementation */
         int (*prepare_write_buffer)(struct usb_serial_port *port,
-                void **dest, size_t size, const void *src, size_t count);
+                                                void *dest, size_t size);
 };
 #define to_usb_serial_driver(d) \
         container_of(d, struct usb_serial_driver, driver)
@@ -345,7 +341,7 @@ extern int usb_serial_generic_submit_read_urb(struct usb_serial_port *port,
                                                  gfp_t mem_flags);
 extern void usb_serial_generic_process_read_urb(struct urb *urb);
 extern int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
-                void **dest, size_t size, const void *src, size_t count);
+                                                void *dest, size_t size);
 extern int usb_serial_handle_sysrq_char(struct tty_struct *tty,
                                         struct usb_serial_port *port,
                                         unsigned int ch);