1 files changed, 165 insertions, 21 deletions

diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c
index be82ea956720..932d6241b787 100644
--- a/drivers/usb/serial/generic.c
+++ b/drivers/usb/serial/generic.c
@@ -63,7 +63,8 @@ struct usb_serial_driver usb_serial_generic_device = {
         .id_table =             generic_device_ids,
         .usb_driver =           &generic_driver,
         .num_ports =            1,
-        .shutdown =             usb_serial_generic_shutdown,
+        .disconnect =           usb_serial_generic_disconnect,
+        .release =              usb_serial_generic_release,
         .throttle =             usb_serial_generic_throttle,
         .unthrottle =           usb_serial_generic_unthrottle,
         .resume =               usb_serial_generic_resume,
@@ -190,6 +191,88 @@ void usb_serial_generic_close(struct usb_serial_port *port)
         generic_cleanup(port);
 }
 
+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;
+        unsigned char *buffer;
+        int status;
+        int towrite;
+        int bwrite = 0;
+
+        dbg("%s - port %d", __func__, port->number);
+
+        if (count == 0)
+                dbg("%s - write request of 0 bytes", __func__);
+
+        while (count > 0) {
+                towrite = (count > port->bulk_out_size) ?
+                        port->bulk_out_size : count;
+                spin_lock_irqsave(&port->lock, flags);
+                if (port->urbs_in_flight >
+                    port->serial->type->max_in_flight_urbs) {
+                        spin_unlock_irqrestore(&port->lock, flags);
+                        dbg("%s - write limit hit\n", __func__);
+                        return bwrite;
+                }
+                port->tx_bytes_flight += towrite;
+                port->urbs_in_flight++;
+                spin_unlock_irqrestore(&port->lock, flags);
+
+                buffer = kmalloc(towrite, GFP_ATOMIC);
+                if (!buffer) {
+                        dev_err(&port->dev,
+                        "%s ran out of kernel memory for urb ...\n", __func__);
+                        goto error_no_buffer;
+                }
+
+                urb = usb_alloc_urb(0, GFP_ATOMIC);
+                if (!urb) {
+                        dev_err(&port->dev, "%s - no more free urbs\n",
+                                __func__);
+                        goto error_no_urb;
+                }
+
+                /* Copy data */
+                memcpy(buffer, buf + bwrite, towrite);
+                usb_serial_debug_data(debug, &port->dev, __func__,
+                                      towrite, 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, towrite,
+                        usb_serial_generic_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);
+                        goto error;
+                }
+
+                /* This urb is the responsibility of the host driver now */
+                usb_free_urb(urb);
+                dbg("%s write: %d", __func__, towrite);
+                count -= towrite;
+                bwrite += towrite;
+        }
+        return bwrite;
+
+error:
+        usb_free_urb(urb);
+error_no_urb:
+        kfree(buffer);
+error_no_buffer:
+        spin_lock_irqsave(&port->lock, flags);
+        port->urbs_in_flight--;
+        port->tx_bytes_flight -= towrite;
+        spin_unlock_irqrestore(&port->lock, flags);
+        return bwrite;
+}
+
 int usb_serial_generic_write(struct tty_struct *tty,
         struct usb_serial_port *port, const unsigned char *buf, int count)
 {
@@ -207,6 +290,11 @@ int usb_serial_generic_write(struct tty_struct *tty,
         /* only do something if we have a bulk out endpoint */
         if (serial->num_bulk_out) {
                 unsigned long flags;
+
+                if (serial->type->max_in_flight_urbs)
+                        return usb_serial_multi_urb_write(tty, port,
+                                                          buf, count);
+
                 spin_lock_irqsave(&port->lock, flags);
                 if (port->write_urb_busy) {
                         spin_unlock_irqrestore(&port->lock, flags);
@@ -252,20 +340,26 @@ int usb_serial_generic_write(struct tty_struct *tty,
         /* no bulk out, so return 0 bytes written */
         return 0;
 }
+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 = 0;
 
         dbg("%s - port %d", __func__, port->number);
-
-        /* FIXME: Locking */
-        if (serial->num_bulk_out) {
-                if (!(port->write_urb_busy))
-                        room = port->bulk_out_size;
+        spin_lock_irqsave(&port->lock, flags);
+        if (serial->type->max_in_flight_urbs) {
+                if (port->urbs_in_flight < serial->type->max_in_flight_urbs)
+                        room = port->bulk_out_size *
+                                (serial->type->max_in_flight_urbs -
+                                 port->urbs_in_flight);
+        } else if (serial->num_bulk_out && !(port->write_urb_busy)) {
+                room = port->bulk_out_size;
         }
+        spin_unlock_irqrestore(&port->lock, flags);
 
         dbg("%s - returns %d", __func__, room);
         return room;
@@ -276,11 +370,16 @@ 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;
         int chars = 0;
+        unsigned long flags;
 
         dbg("%s - port %d", __func__, port->number);
 
-        /* FIXME: Locking */
-        if (serial->num_bulk_out) {
+        if (serial->type->max_in_flight_urbs) {
+                spin_lock_irqsave(&port->lock, flags);
+                chars = port->tx_bytes_flight;
+                spin_unlock_irqrestore(&port->lock, flags);
+        } else if (serial->num_bulk_out) {
+                /* FIXME: Locking */
                 if (port->write_urb_busy)
                         chars = port->write_urb->transfer_buffer_length;
         }
@@ -290,7 +389,8 @@ int usb_serial_generic_chars_in_buffer(struct tty_struct *tty)
 }
 
 
-static void resubmit_read_urb(struct usb_serial_port *port, gfp_t mem_flags)
+void usb_serial_generic_resubmit_read_urb(struct usb_serial_port *port,
+                        gfp_t mem_flags)
 {
         struct urb *urb = port->read_urb;
         struct usb_serial *serial = port->serial;
@@ -311,25 +411,28 @@ static void resubmit_read_urb(struct usb_serial_port *port, gfp_t mem_flags)
                         "%s - failed resubmitting read urb, error %d\n",
                                                         __func__, result);
 }
+EXPORT_SYMBOL_GPL(usb_serial_generic_resubmit_read_urb);
 
 /* Push data to tty layer and resubmit the bulk read URB */
 static void flush_and_resubmit_read_urb(struct usb_serial_port *port)
 {
         struct urb *urb = port->read_urb;
         struct tty_struct *tty = tty_port_tty_get(&port->port);
-        int room;
+        char *ch = (char *)urb->transfer_buffer;
+        int i;
+
+        if (!tty)
+                goto done;
 
         /* Push data to tty */
-        if (tty && urb->actual_length) {
-                room = tty_buffer_request_room(tty, urb->actual_length);
-                if (room) {
-                        tty_insert_flip_string(tty, urb->transfer_buffer, room);
-                        tty_flip_buffer_push(tty);
-                }
+        for (i = 0; i < urb->actual_length; i++, ch++) {
+                if (!usb_serial_handle_sysrq_char(port, *ch))
+                        tty_insert_flip_char(tty, *ch, TTY_NORMAL);
         }
+        tty_flip_buffer_push(tty);
         tty_kref_put(tty);
-
-        resubmit_read_urb(port, GFP_ATOMIC);
+done:
+        usb_serial_generic_resubmit_read_urb(port, GFP_ATOMIC);
 }
 
 void usb_serial_generic_read_bulk_callback(struct urb *urb)
@@ -363,12 +466,24 @@ EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback);
 
 void usb_serial_generic_write_bulk_callback(struct urb *urb)
 {
+        unsigned long flags;
         struct usb_serial_port *port = urb->context;
         int status = urb->status;
 
         dbg("%s - port %d", __func__, port->number);
 
-        port->write_urb_busy = 0;
+        if (port->serial->type->max_in_flight_urbs) {
+                spin_lock_irqsave(&port->lock, flags);
+                --port->urbs_in_flight;
+                port->tx_bytes_flight -= urb->transfer_buffer_length;
+                if (port->urbs_in_flight < 0)
+                        port->urbs_in_flight = 0;
+                spin_unlock_irqrestore(&port->lock, flags);
+        } else {
+                /* Handle the case for single urb mode */
+                port->write_urb_busy = 0;
+        }
+
         if (status) {
                 dbg("%s - nonzero write bulk status received: %d",
                     __func__, status);
@@ -408,11 +523,36 @@ void usb_serial_generic_unthrottle(struct tty_struct *tty)
 
         if (was_throttled) {
                 /* Resume reading from device */
-                resubmit_read_urb(port, GFP_KERNEL);
+                usb_serial_generic_resubmit_read_urb(port, GFP_KERNEL);
+        }
+}
+
+int usb_serial_handle_sysrq_char(struct usb_serial_port *port, unsigned int ch)
+{
+        if (port->sysrq && port->console) {
+                if (ch && time_before(jiffies, port->sysrq)) {
+                        handle_sysrq(ch, tty_port_tty_get(&port->port));
+                        port->sysrq = 0;
+                        return 1;
+                }
+                port->sysrq = 0;
+        }
+        return 0;
+}
+EXPORT_SYMBOL_GPL(usb_serial_handle_sysrq_char);
+
+int usb_serial_handle_break(struct usb_serial_port *port)
+{
+        if (!port->sysrq) {
+                port->sysrq = jiffies + HZ*5;
+                return 1;
         }
+        port->sysrq = 0;
+        return 0;
 }
+EXPORT_SYMBOL_GPL(usb_serial_handle_break);
 
-void usb_serial_generic_shutdown(struct usb_serial *serial)
+void usb_serial_generic_disconnect(struct usb_serial *serial)
 {
         int i;
 
@@ -423,3 +563,7 @@ void usb_serial_generic_shutdown(struct usb_serial *serial)
                 generic_cleanup(serial->port[i]);
 }
 
+void usb_serial_generic_release(struct usb_serial *serial)
+{
+        dbg("%s", __func__);
+}