On Tue, Sep 8, 2015 at 10:04 AM, Paul Osmialowski [off-list ref] wrote:

On Tue, 14 Jul 2015, Linus Walleij wrote:

quoted

I want Shawn and Sascha to look at this as they worked with
other Freescale pin controllers. Especially I want to know if this
is a sibling to the other Freescale controllers or a separate hardware.

If it is *not* a sibling I will *insist* that it use more generic pin
control bindings and move away from the older Freescale-specific
stuff.

No one answered me about that. However, I looked at other Freescale
pinctrl drivers and realised that no one of them (IMX, IMX1, MXS) is
similar to what I need to do for Kinetis, also positions of configuration
bits differ significantly.

OK I insist on using the generic bindings then.

quoted

There exist generic pin config bindings, see
Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt

I suggest to to function+group paring and then use generic pin config
with this driver unless it is a very close sibling to the existing Freescale
pin controllers.

Hint: if it is a sibling, it should share code with them.

There are several drivers doing generic pin control/pin config in the kernel
tree.

I tried to analyze few of the drivers (e.g. zynq family) and can't find
how can I assing clock gate (clock device) to each port (PORTA, PORTB,
PORTC,...) which is required for Kinetis. Is generic pin control capable
to express that requirement or is it a time to desing my own pinctrl
driver (maybe somewhat improved than the one I presented so far)?

That has nothing to do with whether you use generic pinconf or not.
I imagine if a pinctrl unit contains several blocks with individual
clocks you can either:

- Let each block/bank be a device node (this is common) and assign
  each a clocks = <&clock>;

- Keep one node and assign an array of clocks, affected block indicated
  by the index.
  clocks = <&clk1>, <&clk2>, <&clk3>, ... <clkN>;
  This property is in pluralis for this reason I guess.

This pinctrl component is somwehat critical part of BSP. Until it is not
sorted, I don't see a point in releasing what was developed so far.

True that, you need infrastructure first. The more important that it is
as good as possible.

Yours,
Linus Walleij