USB serial linux kernel module

[Andrew Lunn <andrew at lunn dot ch>]

Hi Frank

I worked on the Linux kernel module for the USB serial interface.

Attached is a patch that allows it to compile with 2.6.26-rc9.  The
patch also handles the device when it is in ACM mode. I found that
Linux attaches a device to the ACM interface which just has an
interrupt endpoint. This device is useless. By adding a probe function
i can detect this interface and tell the usb-serial layer to ignore
it.

Please could you test this patch and let me know if it works for
you. If so, i will commit it.

     Thanks
        Andrew

Index: io/usb/serial/slave/current/host/linux/.cvsignore
===================================================================
RCS file: /cvs/ecos/ecos/packages/io/usb/serial/slave/current/host/linux/.cvsignore,v
retrieving revision 1.1
diff -u -r1.1 .cvsignore
--- io/usb/serial/slave/current/host/linux/.cvsignore	12 Jul 2008 10:30:34 -0000	1.1
+++ io/usb/serial/slave/current/host/linux/.cvsignore	13 Jul 2008 12:57:27 -0000
@@ -1,3 +1,7 @@
 .ecos_usbserial.o.d
 .tmp_versions
-*.ko
\ No newline at end of file
+*.ko
+*.cmd
+Module.symvers
+ecos_usbserial.mod.c
+modules.order
Index: io/usb/serial/slave/current/host/linux/ecos_usbserial.c
===================================================================
RCS file: /cvs/ecos/ecos/packages/io/usb/serial/slave/current/host/linux/ecos_usbserial.c,v
retrieving revision 1.1
diff -u -r1.1 ecos_usbserial.c
--- io/usb/serial/slave/current/host/linux/ecos_usbserial.c	12 Jul 2008 10:30:34 -0000	1.1
+++ io/usb/serial/slave/current/host/linux/ecos_usbserial.c	13 Jul 2008 12:57:27 -0000
@@ -45,6 +45,7 @@
 //####DESCRIPTIONEND####
 //===========================================================================
 
+#include <linux/version.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/tty.h>
@@ -55,6 +56,47 @@
 #define VENDOR_ID	0xFFFF
 #define PRODUCT_ID	1
 
+static int debug;
+
+/* Our probe function will detect if the interface has sufficient bulk
+ * in and out endpoints to be useful. The ACM interface only has an
+ * interrupt endpoint, so we don't want a serial device bound to it.
+ */
+
+static int ecos_usbserial_probe(struct usb_serial *serial,
+                                const struct usb_device_id *id)
+{
+        struct usb_interface *interface = serial->interface;
+        struct usb_host_interface *iface_desc; 
+        struct usb_endpoint_descriptor *endpoint;
+        int num_bulk_in = 0;
+        int num_bulk_out = 0;
+        int i;
+        
+        iface_desc = interface->cur_altsetting;
+        for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+                endpoint = &iface_desc->endpoint[i].desc;
+                
+                if (usb_endpoint_is_bulk_in(endpoint)) {
+                        /* we found a bulk in endpoint */
+                        dbg("found bulk in on endpoint %d", i);
+                        ++num_bulk_in;
+                }
+                
+                if (usb_endpoint_is_bulk_out(endpoint)) {
+                        /* we found a bulk out endpoint */
+                        dbg("found bulk out on endpoint %d", i);
+                        ++num_bulk_out;
+                }
+        }
+        
+        if (!num_bulk_out || !num_bulk_out) {
+                info("Ignoring interface, insufficient endpoints");
+                return -ENODEV;
+        }
+        return 0;
+}
+
 static struct usb_device_id id_table[] = {
 	{ USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
 	{ }
@@ -74,11 +116,17 @@
 		.owner			= THIS_MODULE,
 		.name			= "ecos_usbserial",
 	},
-	.id_table			= id_table, 
+	.id_table		= id_table,
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,25) 
 	.num_interrupt_in	= NUM_DONT_CARE,
 	.num_bulk_in		= NUM_DONT_CARE,
 	.num_bulk_out		= NUM_DONT_CARE,
-	.num_ports			= 1
+#else
+        .usb_driver             = &ecos_usbserial_driver,
+#endif
+	.num_ports		= 1,
+        .probe                  = ecos_usbserial_probe,
+
 };
 
 static int __init ecos_usbserial_init(void)
@@ -108,4 +156,6 @@
 module_exit(ecos_usbserial_exit);
 
 MODULE_LICENSE("GPL");
+module_param(debug, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Debug enabled or not");