On Thu, Nov 06, 2014 at 01:33:24AM +0400, Dmitry Eremin-Solenikov wrote:
2014-11-03 16:43 GMT+03:00 Linus Walleij linus.walleij@linaro.org:
Yes that's the point: if you use regmap mmio you get the RMW-locking for free, with the regmap implementation.
Just to be more concrete. Currently locomo_gpio_ack_irq() function uses one lock and one unlock for doing 3 consecutive RMW I I convert locomo to regmap, will that be 3 lock/unlock calls or still one? (Or maybe I'm trying to be over-protective here and adding more lock/unlock cycles won't matter that much?)
You'll get three lock/unlocks, we could add an interface for bulk updates under one lock if it's important though.
Next question: if I have to export regmap to several subdrivers, is it better to have one big regmap or to have one-map-per-driver approach?
One regmap for the physical register map which is shared between all the users.