diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c
index 1a134f9c64f3..3ae17840175c 100644
--- a/drivers/usb/serial/generic.c
+++ b/drivers/usb/serial/generic.c
@@ -1,6 +1,7 @@
/*
* USB Serial Converter Generic functions
*
+ * Copyright (C) 2010 Johan Hovold (jhovold@gmail.com)
* Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
*
* This program is free software; you can redistribute it and/or
@@ -143,6 +144,7 @@ static void generic_cleanup(struct usb_serial_port *port)
{
struct usb_serial *serial = port->serial;
unsigned long flags;
+ int i;
dbg("%s - port %d", __func__, port->number);
@@ -150,6 +152,8 @@ static void generic_cleanup(struct usb_serial_port *port)
/* shutdown any bulk transfers that might be going on */
if (port->bulk_out_size) {
usb_kill_urb(port->write_urb);
+ for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
+ usb_kill_urb(port->write_urbs[i]);
spin_lock_irqsave(&port->lock, flags);
kfifo_reset_out(&port->write_fifo);
@@ -258,46 +262,56 @@ err_urb:
* usb_serial_generic_write_start - kick off an URB write
* @port: Pointer to the &struct usb_serial_port data
*
- * Returns the number of bytes queued on success. This will be zero if there
- * was nothing to send. Otherwise, it returns a negative errno value
+ * Returns zero on success, or a negative errno value
*/
static int usb_serial_generic_write_start(struct usb_serial_port *port)
{
- int result;
- int count;
+ struct urb *urb;
+ int count, result;
unsigned long flags;
+ int i;
+ if (test_and_set_bit_lock(USB_SERIAL_WRITE_BUSY, &port->flags))
+ return 0;
+retry:
spin_lock_irqsave(&port->lock, flags);
- if (port->write_urb_busy || !kfifo_len(&port->write_fifo)) {
+ if (!port->write_urbs_free || !kfifo_len(&port->write_fifo)) {
+ clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
spin_unlock_irqrestore(&port->lock, flags);
return 0;
}
- port->write_urb_busy = 1;
+ i = (int)find_first_bit(&port->write_urbs_free,
+ ARRAY_SIZE(port->write_urbs));
spin_unlock_irqrestore(&port->lock, flags);
+ urb = port->write_urbs[i];
count = port->serial->type->prepare_write_buffer(port,
- &port->write_urb->transfer_buffer,
- port->bulk_out_size, NULL, 0);
- usb_serial_debug_data(debug, &port->dev, __func__,
- count, port->write_urb->transfer_buffer);
- port->write_urb->transfer_buffer_length = count;
-
- /* send the data out the bulk port */
- result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
+ &urb->transfer_buffer,
+ port->bulk_out_size, NULL, 0);
+ urb->transfer_buffer_length = count;
+ usb_serial_debug_data(debug, &port->dev, __func__, count,
+ urb->transfer_buffer);
+ result = usb_submit_urb(urb, GFP_ATOMIC);
if (result) {
dev_err(&port->dev, "%s - error submitting urb: %d\n",
__func__, result);
- /* don't have to grab the lock here, as we will
- retry if != 0 */
- port->write_urb_busy = 0;
+ clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
return result;
}
+ clear_bit(i, &port->write_urbs_free);
spin_lock_irqsave(&port->lock, flags);
port->tx_bytes += count;
spin_unlock_irqrestore(&port->lock, flags);
- return count;
+ /* Try sending off another urb, unless in irq context (in which case
+ * there will be no free urb). */
+ if (!in_irq())
+ goto retry;
+
+ clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
+
+ return 0;
}
/**
@@ -461,6 +475,7 @@ void usb_serial_generic_write_bulk_callback(struct urb *urb)
unsigned long flags;
struct usb_serial_port *port = urb->context;
int status = urb->status;
+ int i;
dbg("%s - port %d", __func__, port->number);
@@ -472,9 +487,13 @@ void usb_serial_generic_write_bulk_callback(struct urb *urb)
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;
- port->write_urb_busy = 0;
+ set_bit(i, &port->write_urbs_free);
spin_unlock_irqrestore(&port->lock, flags);
if (status) {
@@ -576,7 +595,7 @@ int usb_serial_generic_resume(struct usb_serial *serial)
c++;
}
- if (port->write_urb) {
+ if (port->bulk_out_size) {
r = usb_serial_generic_write_start(port);
if (r < 0)
c++;
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 8249fd8381fb..941c2d409f85 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -548,8 +548,12 @@ static void usb_serial_port_work(struct work_struct *work)
static void kill_traffic(struct usb_serial_port *port)
{
+ int i;
+
usb_kill_urb(port->read_urb);
usb_kill_urb(port->write_urb);
+ for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
+ usb_kill_urb(port->write_urbs[i]);
/*
* This is tricky.
* Some drivers submit the read_urb in the
@@ -568,6 +572,7 @@ static void kill_traffic(struct usb_serial_port *port)
static void port_release(struct device *dev)
{
struct usb_serial_port *port = to_usb_serial_port(dev);
+ int i;
dbg ("%s - %s", __func__, dev_name(dev));
@@ -582,6 +587,10 @@ static void port_release(struct device *dev)
usb_free_urb(port->write_urb);
usb_free_urb(port->interrupt_in_urb);
usb_free_urb(port->interrupt_out_urb);
+ for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
+ usb_free_urb(port->write_urbs[i]);
+ kfree(port->bulk_out_buffers[i]);
+ }
kfifo_free(&port->write_fifo);
kfree(port->bulk_in_buffer);
kfree(port->bulk_out_buffer);
@@ -920,6 +929,8 @@ int usb_serial_probe(struct usb_interface *interface,
}
for (i = 0; i < num_bulk_out; ++i) {
+ int j;
+
endpoint = bulk_out_endpoint[i];
port = serial->port[i];
port->write_urb = usb_alloc_urb(0, GFP_KERNEL);
@@ -945,6 +956,28 @@ int usb_serial_probe(struct usb_interface *interface,
endpoint->bEndpointAddress),
port->bulk_out_buffer, buffer_size,
serial->type->write_bulk_callback, port);
+ for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
+ set_bit(j, &port->write_urbs_free);
+ port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
+ if (!port->write_urbs[j]) {
+ dev_err(&interface->dev,
+ "No free urbs available\n");
+ goto probe_error;
+ }
+ port->bulk_out_buffers[j] = kmalloc(buffer_size,
+ GFP_KERNEL);
+ if (!port->bulk_out_buffers[j]) {
+ dev_err(&interface->dev,
+ "Couldn't allocate bulk_out_buffer\n");
+ goto probe_error;
+ }
+ usb_fill_bulk_urb(port->write_urbs[j], dev,
+ usb_sndbulkpipe(dev,
+ endpoint->bEndpointAddress),
+ port->bulk_out_buffers[j], buffer_size,
+ serial->type->write_bulk_callback,
+ port);
+ }
}
if (serial->type->read_int_callback) {
diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h
index a4c99ea390e7..70b6d6b28997 100644
--- a/include/linux/usb/serial.h
+++ b/include/linux/usb/serial.h
@@ -35,6 +35,9 @@ enum port_dev_state {
PORT_UNREGISTERING,
};
+/* USB serial flags */
+#define USB_SERIAL_WRITE_BUSY 0
+
/**
* usb_serial_port: structure for the specific ports of a device.
* @serial: pointer back to the struct usb_serial owner of this port.
@@ -60,10 +63,14 @@ enum port_dev_state {
* @write_urb: pointer to the bulk out struct urb for this port.
* @write_fifo: kfifo used to buffer outgoing data
* @write_urb_busy: port`s writing status
+ * @bulk_out_buffers: pointers to the bulk out buffers for this port
+ * @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
* @write_wait: a wait_queue_head_t used by the port.
* @work: work queue entry for the line discipline waking up.
* @throttled: nonzero if the read urb is inactive to throttle the device
@@ -98,11 +105,16 @@ struct usb_serial_port {
struct urb *write_urb;
struct kfifo write_fifo;
int write_urb_busy;
+
+ unsigned char *bulk_out_buffers[2];
+ struct urb *write_urbs[2];
+ unsigned long write_urbs_free;
__u8 bulk_out_endpointAddress;
int tx_bytes;
int tx_urbs;
+ unsigned long flags;
wait_queue_head_t write_wait;
struct work_struct work;
char throttled;