usb/83353: [patch] ums driver limits number of buttons to 7

[Seán Farley]

>Number:         83353
>Category:       usb
>Synopsis:       [patch] ums driver limits number of buttons to 7
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-usb
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Jul 12 21:30:16 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Seán Farley
>Release:        FreeBSD 5.4-STABLE i386
>Organization:
>Environment:
System: FreeBSD thor.farley.org 5.4-STABLE FreeBSD 5.4-STABLE #0: Thu Jun 23 09:55:25 CDT 2005 root at thor.farley.org:/usr/obj/usr/src/sys/THOR i386

>Description:
The Logitech MX1000 is registered with the ums driver as only having
seven buttons when it has at least twelve.

I tried using the psm driver, but it claimed a maximum of seven buttons
while this mouse has twelve according to one source[1].  I then tried
the ums driver, yet it also claimed only seven buttons.  Fortunately, I
found a NetBSD PR (kern/30248 [2]) concerning the button limit in the
ums driver.  Since sc_buttons is an int, I just bumped up MAX_BUTTONS to
31, and the driver found 16 buttons.  I have no idea where the extra
four buttons are coming from.

More details in my e-mail to freebsd-hackers:
http://lists.freebsd.org/pipermail/freebsd-hackers/2005-July/012652.html

 1. http://floam.sh.nu/index.xhtml?page=guides&section=mx1000
 2. http://www.netbsd.org/cgi-bin/query-pr-single.pl?number=30248

>How-To-Repeat:
>Fix:
sc_buttons is actually an int.  Should it be an unsigned int?

------------- Begin Patch --------------------------
--- sys/dev/usb/ums.c.orig	Mon Jul 11 23:16:37 2005
+++ sys/dev/usb/ums.c	Mon Jul 11 23:16:37 2005
@@ -116,7 +116,7 @@
 #define UMS_T		0x02	/* aa direction available (tilt) */
 #define UMS_SPUR_BUT_UP	0x02	/* spurious button up events */
 	int nbuttons;
-#define MAX_BUTTONS	7	/* chosen because sc_buttons is u_char */
+#define MAX_BUTTONS	31	/* chosen because sc_buttons is u_char */
 
 	u_char		qbuf[QUEUE_BUFSIZE];	/* must be divisable by 3&4 */
 	u_char		dummy[100];	/* XXX just for safety and for now */
------------- End Patch ----------------------------
>Release-Note:
>Audit-Trail:
>Unformatted: