Re: [RFC 0/9] OMAP3 ISP and camera drivers

[Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>]

Hiremath, Vaibhav wrote:
> 
> Thanks,
> Vaibhav Hiremath
> 
>> -----Original Message-----
>> From: DongSoo(Nathaniel) Kim [mailto:dongsoo.kim@gmail.com]
>> Sent: Thursday, March 05, 2009 5:41 AM
>> To: Sakari Ailus
>> Cc: Hiremath, Vaibhav; linux-media@vger.kernel.org; linux-
>> omap@vger.kernel.org; Aguirre Rodriguez, Sergio Alberto; Toivonen
>> Tuukka Olli Artturi; Hiroshi DOYU
>> Subject: Re: [RFC 0/9] OMAP3 ISP and camera drivers
>>
>> Hi Sakari,
>>
>> I'm also facing same issue with Hiremath.
>>
>> Here you are my kernel stack dump.
>>
> [Hiremath, Vaibhav] I was getting same kernel crash,  The reason is -
> 
> Since  isp_probe doesn't get called, leaving omap3isp = NULL. So isp_get will return -EBUSY from the very beginning of function.  And the function "omap34xxcam_device_register" which calls isp_get tries to access vdev->vfd->dev where it crashes. Which is completely wrong, since the vfd gets initialize later part of function
> 
> 
> if (hwc.dev_type == OMAP34XXCAM_SLAVE_SENSOR) {
>     rval = isp_get();
>     if (rval < 0) {
>         dev_err(&vdev->vfd->dev, "can't get ISP, sensor init 					failed\n");
> [Vaibhav] - Here it crashes.
>          goto err;
>      }
> }
> 
> There are some instances where vdev->vfd is being accessed before initializing.

Ooops.

Some parts of those dev_* were just mechanically changed from something 
else. And I think Alexey Klimov already notified me about that problem. 
I'm surprised that it was hit it so soon. ;)

Just removing the dev_err helps to resolve the crash, I guess. You could 
use late_initcall instead of module_init in the sensor, but that's just 
a hack, too.

If you are using modules, please load iommu2 and omap3-iommu before isp-mod.

-- 
Sakari Ailus
sakari.ailus@maxwell.research.nokia.com