[PATCH v2 4/5] drivers/mailbox: Add aspeed ast2400/ast2500 mbox driver

[Benjamin Herrenschmidt]

On Tue, 2017-01-03 at 11:54 +1030, Andrew Jeffery wrote:
> 
> regmap_update_bits() will just write back what it read for the
> untouched bits, which should be 0 in accordance with the datasheet.
> It's not really a change in behaviour as we will still be writing to
> reserved bits, but I think it makes the intent clear.

It wastes cycles though...

Cheers,
Ben.