Hi PrasannaKumar,

On Sunday, 20 August 2017 09:12:12 PDT PrasannaKumar Muralidharan wrote:

quoted

Could you instead perhaps:
 - Just add "syscon" as a second compatible string to the CGU node in the
 
   device tree, but otherwise leave it as-is without the extra
   cgu_registers
   node.
 
 - Have your RNG device node as a child of the CGU node, which should let
 it
 
   pick up the regmap via syscon_node_to_regmap() as it already does.
 
 - Leave the CGU driver as-is, so it can continue accessing memory
 directly
 
   rather than via regmap.

As per my understanding, CGU driver and syscon will map the same
register set. Is that fine?

That should work fine.

It's only risky if you have 2 drivers using the same registers in ways that 
might race with one another or clobber one another's data. In this case each 
of the 2 drivers is using a different subset of registers that just happen to 
be in the same address range, so there shouldn't be an issue.

Thanks,
    Paul