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USB: generic usb serial to new buffering scheme 

the generic driver also had its own buffering.

Signed-off-by: Oliver Neukum <oneukum@suse.de_
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Oliver Neukum 2007-05-07 12:09:33 +02:00 committed by Greg Kroah-Hartman
parent 39892da44b
commit 1abdeeb1d5
1 changed files with 34 additions and 35 deletions
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65
drivers/usb/serial/generic.c
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@ -281,45 +281,54 @@ int usb_serial_generic_chars_in_buffer (struct usb_serial_port *port)
return (chars);
}
/* Push data to tty layer and resubmit the bulk read URB */
static void flush_and_resubmit_read_urb (struct usb_serial_port *port)
static void resubmit_read_urb(struct usb_serial_port *port, gfp_t mem_flags)
{
struct usb_serial *serial = port->serial;
struct urb *urb = port->read_urb;
struct tty_struct *tty = port->tty;
struct usb_serial *serial = port->serial;
int result;
/* Push data to tty */
if (tty && urb->actual_length) {
tty_buffer_request_room(tty, urb->actual_length);
tty_insert_flip_string(tty, urb->transfer_buffer, urb->actual_length);
tty_flip_buffer_push(tty); /* is this allowed from an URB callback ? */
}
/* Continue reading from device */
usb_fill_bulk_urb (port->read_urb, serial->dev,
usb_fill_bulk_urb (urb, serial->dev,
usb_rcvbulkpipe (serial->dev,
port->bulk_in_endpointAddress),
port->read_urb->transfer_buffer,
port->read_urb->transfer_buffer_length,
urb->transfer_buffer,
urb->transfer_buffer_length,
((serial->type->read_bulk_callback) ?
serial->type->read_bulk_callback :
usb_serial_generic_read_bulk_callback), port);
result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
result = usb_submit_urb(urb, mem_flags);
if (result)
dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
}
/* 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 = port->tty;
int room;
/* 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); /* is this allowed from an URB callback ? */
}
}
resubmit_read_urb(port, GFP_ATOMIC);
}
void usb_serial_generic_read_bulk_callback (struct urb *urb)
{
struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
unsigned char *data = urb->transfer_buffer;
int is_throttled;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
if (urb->status) {
if (unlikely(urb->status != 0)) {
dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
return;
}
@ -327,21 +336,11 @@ void usb_serial_generic_read_bulk_callback (struct urb *urb)
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
/* Throttle the device if requested by tty */
if (urb->actual_length) {
spin_lock_irqsave(&port->lock, flags);
is_throttled = port->throttled = port->throttle_req;
spin_unlock_irqrestore(&port->lock, flags);
if (is_throttled) {
/* Let the received data linger in the read URB;
* usb_serial_generic_unthrottle() will pick it
* up later. */
dbg("%s - throttling device", __FUNCTION__);
return;
}
}
spin_lock(&port->lock);
if (!(port->throttled = port->throttle_req))
/* Handle data and continue reading from device */
flush_and_resubmit_read_urb(port);
spin_unlock(&port->lock);
}
EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback);
@ -388,8 +387,8 @@ void usb_serial_generic_unthrottle (struct usb_serial_port *port)
spin_unlock_irqrestore(&port->lock, flags);
if (was_throttled) {
/* Handle pending data and resume reading from device */
flush_and_resubmit_read_urb(port);
/* Resume reading from device */
resubmit_read_urb(port, GFP_KERNEL);
}
}