On Mon, Aug 5, 2013 at 9:09 AM, Kim, Milo [off-list ref] wrote:

In the meantime, I've reviewed the pin control subsystem,
I think it is not the best way to implement LP3943 driver.
The GPIO controller is OK, but I can't make flexible pin assignment for the PWM
operation.
For example, multiple output pins can be controlled by one PWM generator.
These pin assignment are configurable - not fixed type.

So it's more like a router than a PWM goes out on a certain pin,
you can route the same PWM output to e.g. all pins if you want
to, and each pin will have its own driver stage?

And pinmux are only two cases - GPIO and PWM.
I think current driver structure is better because LP3943 uses very limited
pinctrl functionalities.
Any suggestion for this?

Well if you'r going to do things like remuxing this dynamically
you'd use the pinctrl subsystem. But if you only want to pass
a certain static configuration from e.g. platform data or the device
tree, it can be done like this.

Yours,
Linus Walleij