spca5xx webcam driver not compiling on 2.6.13-rc4-RT-V0.7.52-07

["Shayne O'Connor" <forums@machinehasnoagenda.com>]

the spca5xx webcam driver module compiles/installs/runs fine (a few 
compilation warnings, but nothing much) on vanilla 2.6.x kernels, but 
won't succeed on one patched with ingo's realtime pre-emption patches.

*********************************************

[root@localhost spca5xx-20050701]# make
    Building SPCA5XX driver for 2.5/2.6 kernel.
    Remember: you must have read/write access to your kernel source tree.
make -C /lib/modules/`uname -r`/build 
SUBDIRS=/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701 
modules
make[1]: Entering directory 
`/home/mrmachine/my_documents/applications/linux/system+admin/linux-2.6.12'
   CC [M] 
/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/spca5xx.o
In file included from 
/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/spca5xx.c:763:
/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/mr97311.h: 
In function `pcam_start':
/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/mr97311.h:391: 
warning: ISO C90 forbids mixed declarations and code
/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/spca5xx.c: 
In function `spca5xx_probe':
/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/spca5xx.c:8663: 
error: `SPIN_LOCK_UNLOCKED' undeclared (first use in this function)
/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/spca5xx.c:8663: 
error: (Each undeclared identifier is reported only once
/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/spca5xx.c:8663: 
error: for each function it appears in.)
make[2]: *** 
[/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701/drivers/usb/spca5xx.o] 
Error 1
make[1]: *** 
[_module_/home/mrmachine/my_documents/applications/linux/video/spca5xx-20050701] 
Error 2
make[1]: Leaving directory 
`/home/mrmachine/my_documents/applications/linux/system+admin/linux-2.6.12'
make: *** [default] Error 2

**********************************************************************

all the warnings up to the error occur on a vanilla kernel compilation, 
but installs anyway ... i know "SPIN_LOCK_UNLOCKED" has something to do 
with ingo's patch, so i emailed the spca5xx author to see if he knew 
what to do:

> Shayne,
> Try to change 'SPIN_LOCK_UNLOCKED'  by some thing to initialize the spin  :) 
> regards

i'm guessing it's these lines in spca5xx.c that i have to change:

*****************************************

if (!spca50x_configure (spca50x))
     {
       spca50x->user = 0;
       init_MUTEX (&spca50x->lock);	/* to 1 == available */
       init_MUTEX (&spca50x->buf_lock);
       spca50x->v4l_lock = SPIN_LOCK_UNLOCKED;
       spca50x->buf_state = BUF_NOT_ALLOCATED;
     }
   else
     {
       err ("Failed to configure camera");
       goto error;
     }

****************************************

i've looked through the archives for some clue as to what to change it 
to, but being a bit on the newbie side, haven't had any luck ...

please CC me on any replies!

thanx

shayne