controlD64 device node not found

akhil.mv · 10-21-2017, 04:32 AM

Hi all,
In earlier versions of Linux(4.09), there is a device node /dev/dri/controlD64 for my drm device, but in Linux kernel 4.12, no such node available. Only card0 is available. Is this an expected behavior in latest versions of Linux.
Please share your comments.

Regards
Akhil

business_kid · 10-22-2017, 01:15 PM

That's more udev related than kernel related. There's major/minor numbers for each device. If you run 'ls -l /dev/dri/card0' you'll see them Compare them to your old system.

akhil.mv · 10-26-2017, 04:16 AM

Both kernel versions(4.09 and 4.12) have the /dev/dri/card0 node. But for 4.09 the node /dev/dri/controlD64 is available and this node is not available in 4.12 kernel.
Do you know the reason for this?

business_kid · 10-26-2017, 12:43 PM

Quote:

Originally Posted by akhil.mv

Both kernel versions(4.09 and 4.12) have the /dev/dri/card0 node. But for 4.09 the node /dev/dri/controlD64 is available and this node is not available in 4.12 kernel.
Do you know the reason for this?

If your software is from before this change, and your kernel from after, remember: This is linux; there's always symlimks to get you out of things like that :-D.
No, I don't know, but you can always grok the ever-increasing kernel ChangeLog or, if you're really a sucker for punishment, join the Linux Kernel Mailing List; You'll be treated every day to megabytes of ill-mannered sparring and impoliteness besides top quality technical expositions on uninteresting points.