#include <linux/usb/serial.h>
#include <asm/uaccess.h>
-static int generic_probe(struct usb_interface *interface,
- const struct usb_device_id *id);
-
static int debug;
#ifdef CONFIG_USB_SERIAL_GENERIC
+
+static int generic_probe(struct usb_interface *interface,
+ const struct usb_device_id *id);
+
static __u16 vendor = 0x05f9;
static __u16 product = 0xffff;
.num_bulk_out = NUM_DONT_CARE,
.num_ports = 1,
.shutdown = usb_serial_generic_shutdown,
+ .throttle = usb_serial_generic_throttle,
+ .unthrottle = usb_serial_generic_unthrottle,
+ .resume = usb_serial_generic_resume,
};
static int generic_probe(struct usb_interface *interface,
{
struct usb_serial *serial = port->serial;
int result = 0;
+ unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
if (port->tty)
port->tty->low_latency = 1;
- /* if we have a bulk interrupt, start reading from it */
+ /* clear the throttle flags */
+ spin_lock_irqsave(&port->lock, flags);
+ port->throttled = 0;
+ port->throttle_req = 0;
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ /* if we have a bulk endpoint, start reading from it */
if (serial->num_bulk_in) {
/* Start reading from the device */
usb_fill_bulk_urb (port->read_urb, serial->dev,
}
}
+int usb_serial_generic_resume(struct usb_serial *serial)
+{
+ struct usb_serial_port *port;
+ int i, c = 0, r;
+
+ for (i = 0; i < serial->num_ports; i++) {
+ port = serial->port[i];
+ if (port->open_count && port->read_urb) {
+ r = usb_submit_urb(port->read_urb, GFP_NOIO);
+ if (r < 0)
+ c++;
+ }
+ }
+
+ return c ? -EIO : 0;
+}
+
void usb_serial_generic_close (struct usb_serial_port *port, struct file * filp)
{
dbg("%s - port %d", __FUNCTION__, port->number);
return (chars);
}
+
+static void resubmit_read_urb(struct usb_serial_port *port, gfp_t mem_flags)
+{
+ struct urb *urb = port->read_urb;
+ struct usb_serial *serial = port->serial;
+ int result;
+
+ /* Continue reading from device */
+ usb_fill_bulk_urb (urb, serial->dev,
+ usb_rcvbulkpipe (serial->dev,
+ port->bulk_in_endpointAddress),
+ 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(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;
- struct usb_serial *serial = port->serial;
- struct tty_struct *tty;
unsigned char *data = urb->transfer_buffer;
- int result;
+ int status = urb->status;
dbg("%s - port %d", __FUNCTION__, port->number);
- if (urb->status) {
- dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
+ if (unlikely(status != 0)) {
+ dbg("%s - nonzero read bulk status received: %d",
+ __FUNCTION__, status);
return;
}
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
- tty = port->tty;
- if (tty && urb->actual_length) {
- tty_buffer_request_room(tty, urb->actual_length);
- tty_insert_flip_string(tty, data, urb->actual_length);
- tty_flip_buffer_push(tty);
- }
-
- /* Continue trying to always read */
- usb_fill_bulk_urb (port->read_urb, serial->dev,
- usb_rcvbulkpipe (serial->dev,
- port->bulk_in_endpointAddress),
- port->read_urb->transfer_buffer,
- port->read_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);
- if (result)
- dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
+ /* Throttle the device if requested by tty */
+ 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);
void usb_serial_generic_write_bulk_callback (struct urb *urb)
{
struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
+ int status = urb->status;
dbg("%s - port %d", __FUNCTION__, port->number);
port->write_urb_busy = 0;
- if (urb->status) {
- dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
+ if (status) {
+ dbg("%s - nonzero write bulk status received: %d",
+ __FUNCTION__, status);
return;
}
}
EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
+void usb_serial_generic_throttle (struct usb_serial_port *port)
+{
+ unsigned long flags;
+
+ dbg("%s - port %d", __FUNCTION__, port->number);
+
+ /* Set the throttle request flag. It will be picked up
+ * by usb_serial_generic_read_bulk_callback(). */
+ spin_lock_irqsave(&port->lock, flags);
+ port->throttle_req = 1;
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+void usb_serial_generic_unthrottle (struct usb_serial_port *port)
+{
+ int was_throttled;
+ unsigned long flags;
+
+ dbg("%s - port %d", __FUNCTION__, port->number);
+
+ /* Clear the throttle flags */
+ spin_lock_irqsave(&port->lock, flags);
+ was_throttled = port->throttled;
+ port->throttled = port->throttle_req = 0;
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ if (was_throttled) {
+ /* Resume reading from device */
+ resubmit_read_urb(port, GFP_KERNEL);
+ }
+}
+
void usb_serial_generic_shutdown (struct usb_serial *serial)
{
int i;
projects / linux-2.6-omap-h63xx.git / blobdiff