add high-speed usb serial fix from Junxion (closes: #2274)

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@8549 3c298f89-4303-0410-b956-a3cf2f4a3e73

target/linux/generic-2.6/patches-2.6.22/601-usb_serial_endpoint_size.patch

@@ -0,0 +1,25 @@
+--- linux-2.6.22.4-old/drivers/usb/serial/usb-serial.c	2007-08-21 06:33:06.000000000 +0200
++++ linux-2.6.22.4-new/drivers/usb/serial/usb-serial.c	2007-08-26 15:43:11.000000000 +0200
+@@ -56,6 +56,7 @@
+    drivers depend on it.
+ */
+ 
++static ushort maxSize = 0;
+ static int debug;
+ static struct usb_serial *serial_table[SERIAL_TTY_MINORS];	/* initially all NULL */
+ static spinlock_t table_lock;
+@@ -864,7 +865,7 @@
+ 			dev_err(&interface->dev, "No free urbs available\n");
+ 			goto probe_error;
+ 		}
+-		buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
++		buffer_size = (endpoint->wMaxPacketSize > maxSize) ? endpoint->wMaxPacketSize : maxSize;
+ 		port->bulk_in_size = buffer_size;
+ 		port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
+ 		port->bulk_in_buffer = kmalloc (buffer_size, GFP_KERNEL);
+@@ -1245,3 +1246,5 @@
+ 
+ module_param(debug, bool, S_IRUGO | S_IWUSR);
+ MODULE_PARM_DESC(debug, "Debug enabled or not");
++module_param(maxSize, ushort,0);
++MODULE_PARM_DESC(maxSize,"User specified USB endpoint size");