Re: [PATCH 00/16] Marvell EBU thermal sensor consolidation

[Andrew Lunn <andrew@lunn.ch>]

On Wed, Mar 20, 2013 at 07:36:21PM -0300, Ezequiel Garcia wrote:
> This patchset is my first attempt at adding basic thermal sensor
> support on Armada 370 and Armada XP.
> 
> Given Armada 370/XP and the other Marvell SoC with thermal support,
> namely Kirkwood and Dove, have fairly similar thermal devices it 
> made sense to integrate all of them into a single driver: mvebu-thermal.

Hi Ezequiel

I went this way to start with, merging Dove, Kirkwood and something
which nearly worked for 370. But then i looked at the code, at how
little is actually shared, and went back to separate drivers.

Kirkwood has no control registers, so needs a special case in the probe.
The bit location of the temperate value moves around in the register.
Each SoC needs its own initialization sequence.
Each SoC needs its own is_valid() function.
Each Soc needs its own formula to convert to milli centigrad.

I've never seen the datasheets for 370/XP, just a list of registers for
370. But i get the impression it has two temperate sensors, so should
export two values?

Also, kirkwood will never be built into the same kernel as
Dove/370/XP.  So we end up with "bloat" in the driver, or at least a
collection of #ifdefs.

In the end, i decided it was simpler and cleaner to just have separate
drivers. This is something which we should think about and discuss.

	 Andrew