From c48dea5195a3bc374c6357df7ec1ffc3106d22b4 Mon Sep 17 00:00:00 2001
From: Tim 'mithro' Ansell <mithro@mithis.com>
Date: Thu, 2 Jul 2015 01:17:49 +1000
Subject: [PATCH] Allow the vizzini module to be installed side-by-side with
 cdc-acm.

 * Use a dynamically allocated major device number.

 * Use the tty name of /dev/ttyVIZx so it doesn't conflict with other devices.

 * Create a udev rule which makes sure the device is bound to the vizzini
   module. This is needed if the vizzini module is loaded *after* the cdc-acm
   module as drivers are checked in the order they have been loaded and the
   cdc-acm registers for the device class exported by the device.

 * Adding slightly better debug messages.
---
 99-vizzini.rules |  1 +
 Makefile         |  5 +++++
 debian/changelog |  6 ++++++
 debian/rules     |  3 +++
 vizzini.c        | 11 +++++++----
 vizzini.h        |  1 -
 6 files changed, 22 insertions(+), 5 deletions(-)
 create mode 100644 99-vizzini.rules

diff --git a/99-vizzini.rules b/99-vizzini.rules
new file mode 100644
index 0000000..61ebe5c
--- /dev/null
+++ b/99-vizzini.rules
@@ -0,0 +1 @@
+SUBSYSTEM=="usb", ATTR{idVendor}=="04e2", RUN+="/bin/sh -c 'echo -n %k:1.0 >/sys/bus/usb/drivers/cdc_acm/unbind; echo -n %k:1.0 >/sys/bus/usb/drivers/vizzini/bind'"
diff --git a/Makefile b/Makefile
index 750a450..898f64d 100644
--- a/Makefile
+++ b/Makefile
@@ -13,3 +13,8 @@ modules_install:
 
 clean:
 	rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c .tmp_versions vtty
+
+install-rules: 99-vizzini.rules
+	cp $< "/etc/udev/rules.d/99-vizzini.rules"
+	udevadm control --reload-rules
+	udevadm trigger --attr-match=idVendor=04e2 --verbose
diff --git a/debian/changelog b/debian/changelog
index fdc80e0..9b9bc66 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+vizzini (1.0.0-3) unstable; urgency=low
+
+  * Now can be loaded side-by-side with the cdc-acm module.
+
+ -- Tim 'mithro' Ansell <mithro@mithis.com>  Thu, 02 Jul 2015 01:34:00 +1030
+
 vizzini (1.0.0-2) unstable; urgency=low
 
   * Now based on https://github.com/shenki/exar-uart-driver instead of https://github.com/ardje/vizzini
diff --git a/debian/rules b/debian/rules
index 42506bb..1faffd7 100755
--- a/debian/rules
+++ b/debian/rules
@@ -27,6 +27,8 @@ binary-modules:
 	dh_installdocs
 	dh_installchangelogs
 	dh_installmodules
+	cp debian/vizzini.udev debian/$(PKGNAME).udev
+	dh_installudev --priority=99
 	dh_compress
 	dh_fixperms
 	dh_installdeb
@@ -50,6 +52,7 @@ install: build
 	dh_installdirs -p$(psource)  usr/src/modules/$(sname)/debian
 	cp Makefile README* vizzini.c vizzini.h vzioctl.h $(DESTDIR)
 	cp debian/*modules.in* debian/control debian/rules debian/changelog debian/copyright debian/compat $(DESTDIR)/debian
+	cp 99-vizzini.rules $(DESTDIR)/debian/vizzini.udev
 	cd debian/$(psource)/usr/src && tar c modules | bzip2 -9 > $(sname).tar.bz2 && rm -rf modules
 	dh_install
 
diff --git a/vizzini.c b/vizzini.c
index 9e085c0..85e5d76 100644
--- a/vizzini.c
+++ b/vizzini.c
@@ -1853,11 +1853,13 @@ static int __init xr21v141x_init(void)
 {
 	int retval;
 	xr21v141x_tty_driver = alloc_tty_driver(XR21V141X_TTY_MINORS);
-	if (!xr21v141x_tty_driver)
+	if (!xr21v141x_tty_driver) {
+		printk(KERN_INFO KBUILD_MODNAME ": alloc_tty_driver(%d) failed\n", XR21V141X_TTY_MINORS);
 		return -ENOMEM;
+        }
 	xr21v141x_tty_driver->driver_name = "vizzini",
-	xr21v141x_tty_driver->name = "ttyUSB",
-	xr21v141x_tty_driver->major = XR21V141X_TTY_MAJOR,
+	xr21v141x_tty_driver->name = "ttyVIZ",
+	xr21v141x_tty_driver->major = 0, // Dynamically allocate the major number
 	xr21v141x_tty_driver->minor_start = 0,
 	xr21v141x_tty_driver->type = TTY_DRIVER_TYPE_SERIAL,
 	xr21v141x_tty_driver->subtype = SERIAL_TYPE_NORMAL,
@@ -1869,12 +1871,14 @@ static int __init xr21v141x_init(void)
 
 	retval = tty_register_driver(xr21v141x_tty_driver);
 	if (retval) {
+		printk(KERN_INFO KBUILD_MODNAME ": tty_register_driver failed\n");
 		put_tty_driver(xr21v141x_tty_driver);
 		return retval;
 	}
 
 	retval = usb_register(&xr21v141x_driver);
 	if (retval) {
+		printk(KERN_INFO KBUILD_MODNAME ": usb_register failed\n");
 		tty_unregister_driver(xr21v141x_tty_driver);
 		put_tty_driver(xr21v141x_tty_driver);
 		return retval;
@@ -1898,4 +1902,3 @@ module_exit(xr21v141x_exit);
 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_LICENSE("GPL");
-MODULE_ALIAS_CHARDEV_MAJOR(ACM_TTY_MAJOR);
diff --git a/vizzini.h b/vizzini.h
index 1fa31e6..9fe8638 100644
--- a/vizzini.h
+++ b/vizzini.h
@@ -195,7 +195,6 @@
  * Major and minor numbers.
  */
 
-#define XR21V141X_TTY_MAJOR		166
 #define XR21V141X_TTY_MINORS		32
 
 #define USB_RT_ACM		(USB_TYPE_CLASS | USB_RECIP_INTERFACE)
-- 
2.39.2