Hi Rob,

2015-12-09 4:41 GMT+01:00 Rob Herring [off-list ref]:

On Tue, Dec 08, 2015 at 01:45:04PM +0100, Maxime Coquelin wrote:

quoted

Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
---
 .../bindings/pinctrl/st,stm32-pinctrl.txt          | 126 +++++++++++++++++++++
 1 file changed, 126 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt

diff --git a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt
new file mode 100644
index 0000000..7b4800c
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt

@@ -0,0 +1,126 @@
+* STM32 GPIO and Pin Mux/Config controller
+
+STMicroelectronics's STM32 MCUs intregrate a GPIO and Pin mux/config hardware
+controller. It controls the input/output settings on the available pins and
+also provides ability to multiplex and configure the output of various on-chip
+controllers onto these pads.
+
+Pin controller node:
+Required properies:
+ - compatible: value should be one of the following:
+   (a) "st,stm32f429-pinctrl"
+ - #address-cells: The value of this property must be 1
+ - #size-cells       : The value of this property must be 1
+ - ranges    : defines mapping between pin controller node (parent) to
+   gpio-bank node (children).
+ - pins-are-numbered: Specify the subnodes are using numbered pinmux to
+   specify pins.
+
+GPIO controller/bank node:
+Required properties:
+ - gpio-controller : Indicates this device is a GPIO controller
+ - #gpio-cells         : Should be two.
+                     The first cell is the pin number
+                     The second one is the polarity:
+                             - 0 for active high
+                             - 1 for active low
+ - reg                 : The gpio address range, relative to the pinctrl range
+ - clocks      : clock that drives this bank
+ - st,bank-name        : Should be a name string for this bank as specified in
+   the datasheet

How do you intend to use this? We should come up with something generic
or drop it.

Good point.
It is used to have a meaningful name set in gpio_chip's label.
I see two alternatives:
 1. replace "st,bank-name" with label
 2. use aliases, and construct label in driver with something like:
     kasprintf(GFP_KERNEL, "GPIO%c", 'A' + of_alias_get_id(np, "gpio"));

What do you prefer?
Do you have other ideas?

Thanks,
Maxime