Appropriate method of io remapping a single memory location?

[Carlo Caione]

On Tue, May 5, 2015 at 12:18 PM,  <maitysanchayan at gmail.com> wrote:
> Hello,
>
> I am adding a small piece of code to expose SoC specific information
> while following the below information, for a Cortex A5 platform.
>
> https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-devices-soc
>
> For the SoC device attribute revision, I need to access a location 0x80
> for reading the ROM revision information. I am kinda stuck at trying to
> find the appropriate way to read this location.
>
> The devm_ioremap* functions take a device pointer which I can manage but
> they also need a struct resource argument and devm_ioremap requries a
> resource_size_t as well. Having only a specific location to read,
> without having any struct resource what would be the appropriate way to
> get this information.

If the register / memory location is only used for that specific
purpose then using something like reg = <0x00000080 0x4> in the DT
node is perfectly fine. But if the register is part of a larger device
you can use a syscon device to represent that.

-- 
Carlo Caione