Hi list,<br><br>I&#39;m a little bit confused about an issue I hope you can shed some light on it.<br><br>Right now I&#39;m trying to write a driver for a vustom piece of hardware, which resides on a VME bus. I&#39;m using 
2.6.15 kernel with an VME driver and can access the device through normal ioctl()&#39;s, read(), writes()&#39;s. My confiusion comes from the fact that from my driver I have to read some registers when the custom device generates an interrupt, but since this happens in kernel space, I&#39;m not sure wheather I can use the normal IO controls or not. Further confusion brings the fact that there is already a working device for Solaris/SPARC for this device, and there the device driver uses some kind of leaf driver. Is the concept of leaf and nexus drivers, which is present in Solaris, also present in Linux? I tried to find some information about differences in the two operating systems on that level but only ended up in the &quot;Writing device drivers&quot; tutorials on 
<a href="http://doc.sun.com">doc.sun.com</a>.<br><br>If anybody can give me some clue about this leaf stuff I&#39;ll be thankful.<br><br>Best regards,<br>Konstantin<br><br>