Re: [matroxfb] Second head is on but fb1 not accessible

Re: [matroxfb] Second head is on but fb1 not accessible

[Petr Vandrovec]

On  9 Feb 04 at 14:09, Jan Mynarik wrote:

> I'm using matroxfb from (2.6.2 and 2.6.0 patch from
> http://platan.vc.cvut.cz/ftp/pub/linux/matrox-latest/ tested too) on
> G400 (32MB dual head). Other details are SMP, preempt kernel, Debian
> unstable.
> 
> Cannot open /dev/fb1: No such device

Make sure that /dev/fb1 is character device 29,1 and not 29,32. 2.2.x kernels
accept 29,32 only, 2.4.x accept both, and 2.6.x accept 29,1 only.
                                                Petr Vandrovec
                                                

Re: [matroxfb] Second head is on but fb1 not accessible

[Petr Vandrovec]

On  9 Feb 04 at 14:21, Jan Mynarik wrote:
> > Make sure that /dev/fb1 is character device 29,1 and not 29,32. 2.2.x kernels
> > accept 29,32 only, 2.4.x accept both, and 2.6.x accept 29,1 only.
> 
> Thanks for super-fast reply :-), I did think it could be related to
> minor device number.
> 
> But anyway, shouldn't I have at least console visible on the second head
> (even if /dev/fb1 is not accessible)? I tested it by attaching my
> monitor to second head and nothing appeared.

Only G450/G550 display same picture (from CRTC1) on all outputs, MAVEN output
is by default disabled until you'll configure it with 'matroxset'. 
If you want same picture on both outputs even for G400, it should be 
enough to replace

ACCESS_FBINFO(outputs[1]).src = MATROXFB_SRC_NONE;

with

ACCESS_FBINFO(outputs[1]).src = MATROXFB_SRC_CRTC1;

in maven_init_client() in drivers/video/matrox/matroxfb_maven.c.
(it is not enabled by default as on G400 you can have either Maven output
or DFP output but not both; G450/G550 does not have such restriction,
and so on G450/G550 all three outputs show same picture by default).
                                                    Petr Vandrovec
                                                    vandrove@vc.cvut.cz
                                                    

[matroxfb] Second head is on but fb1 not accessible

[Jan Mynarik]

Hi,

I'm using matroxfb from (2.6.2 and 2.6.0 patch from
http://platan.vc.cvut.cz/ftp/pub/linux/matrox-latest/ tested too) on
G400 (32MB dual head). Other details are SMP, preempt kernel, Debian
unstable.

Framebuffer on first head is working fine, the problem is that dmesg
says that second head is on (matroxfb_crtc2: secondary head of fb0 was
registered as fb1) but it's not true. Every tool (matroxset, fbset, ..)
trying to touch fb1 gets:

Cannot open /dev/fb1: No such device

I think my configuration is OK, it's done according to several
framebuffer TV-out howtos.

I can't send actual kernel config file or dmesg at the moment, won't be
at affected computer till weekend.

Does anyone else has the same problem? Any suggestions?

Thanks,

Jan "Pogo" Mynarik

-- 
Jan Mynarik <mynarikj@phoenix.inf.upol.cz>

Re: [matroxfb] Second head is on but fb1 not accessible

[Jan Mynarik]

> Make sure that /dev/fb1 is character device 29,1 and not 29,32. 2.2.x kernels
> accept 29,32 only, 2.4.x accept both, and 2.6.x accept 29,1 only.

Thanks for super-fast reply :-), I did think it could be related to
minor device number.

But anyway, shouldn't I have at least console visible on the second head
(even if /dev/fb1 is not accessible)? I tested it by attaching my
monitor to second head and nothing appeared.

Jan "Pogo" Mynarik

-- 
Jan Mynarik <mynarikj@phoenix.inf.upol.cz>