@@ -41,6 +41,7 @@ struct opticon_private {
bool rts;
bool cts;
int outstanding_urbs;
+ int outstanding_bytes;
};
@@ -169,6 +170,7 @@ static void opticon_write_control_callback(struct urb *urb)
spin_lock_irqsave(&priv->lock, flags);
--priv->outstanding_urbs;
+ priv->outstanding_bytes -= urb->transfer_buffer_length;
spin_unlock_irqrestore(&priv->lock, flags);
usb_serial_port_softint(port);
@@ -182,8 +184,8 @@ static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
struct urb *urb;
unsigned char *buffer;
unsigned long flags;
- int status;
struct usb_ctrlrequest *dr;
+ int ret = -ENOMEM;
spin_lock_irqsave(&priv->lock, flags);
if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
@@ -192,19 +194,16 @@ static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
return 0;
}
priv->outstanding_urbs++;
+ priv->outstanding_bytes += count;
spin_unlock_irqrestore(&priv->lock, flags);
buffer = kmalloc(count, GFP_ATOMIC);
- if (!buffer) {
- count = -ENOMEM;
+ if (!buffer)
goto error_no_buffer;
- }
urb = usb_alloc_urb(0, GFP_ATOMIC);
- if (!urb) {
- count = -ENOMEM;
+ if (!urb)
goto error_no_urb;
- }
memcpy(buffer, buf, count);
@@ -213,10 +212,8 @@ static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
/* The connected devices do not have a bulk write endpoint,
* to transmit data to de barcode device the control endpoint is used */
dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
- if (!dr) {
- count = -ENOMEM;
+ if (!dr)
goto error_no_dr;
- }
dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT;
dr->bRequest = 0x01;
@@ -230,12 +227,9 @@ static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
opticon_write_control_callback, port);
/* send it down the pipe */
- status = usb_submit_urb(urb, GFP_ATOMIC);
- if (status) {
- dev_err(&port->dev,
- "%s - usb_submit_urb(write endpoint) failed status = %d\n",
- __func__, status);
- count = status;
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret) {
+ dev_err(&port->dev, "failed to submit write urb: %d\n", ret);
goto error;
}
@@ -253,8 +247,10 @@ static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
error_no_buffer:
spin_lock_irqsave(&priv->lock, flags);
--priv->outstanding_urbs;
+ priv->outstanding_bytes -= count;
spin_unlock_irqrestore(&priv->lock, flags);
- return count;
+
+ return ret;
}
static int opticon_write_room(struct tty_struct *tty)
@@ -279,6 +275,20 @@ static int opticon_write_room(struct tty_struct *tty)
return 2048;
}
+static int opticon_chars_in_buffer(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 count;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ count = priv->outstanding_bytes;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return count;
+}
+
static int opticon_tiocmget(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
@@ -383,6 +393,7 @@ static struct usb_serial_driver opticon_device = {
.open = opticon_open,
.write = opticon_write,
.write_room = opticon_write_room,
+ .chars_in_buffer = opticon_chars_in_buffer,
.throttle = usb_serial_generic_throttle,
.unthrottle = usb_serial_generic_unthrottle,
.get_serial = get_serial_info,
Add a chars_in_buffer() implementation so that the tty layer will wait for outgoing buffered data to be drained when needed (e.g. on final close()). Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/usb/serial/opticon.c | 45 ++++++++++++++++++++++-------------- 1 file changed, 28 insertions(+), 17 deletions(-)