On 27/01/13 14:07, Stijn Devriendt wrote:

quoted

+Example:
+
+        blockgpio {
+                compatible = "linux,gpio-block";
+
+                block0 {
+                        gpios = <&gpio 3 0 0>,
+                                <&gpio 3 1 0>;
+                };
+                block1 {
+                        gpios = <&gpio 4 1 0>,
+                                <&gpio 4 3 0>,
+                                <&gpio 4 2 0>,
+                                <&gpio 4 4 0>,
+                                <&gpio 4 5 0>,
+                                <&gpio 4 6 0>,
+                                <&gpio 4 7 0>,
+                                <&gpio 4 8 0>,
+                                <&gpio 4 9 0>,
+                                <&gpio 4 10 0>,
+                                <&gpio 4 19 0>;
+                };
+        };

How do you see bindings for other kinds of drivers?

In my patchset, it's possible for other drivers to use gpio-blocks.
One example we have is a power sequencer with 2 pins attached
to GPIO pins. These 2 pins form a 2bit word to select power margining.
These 2 pins need to be set synchronously (as otherwise when going
from profile 0 to profile 3 you pass either profile 1 or profile 2 which
could be bad for hardware)

In the device-tree this is specified as:

powr at 0x20 {
   // other properties

  gpios = <&gpio 4 0
               &gpio 5 0>;
};

Is this kind of integration also possible?

You can reference the gpio block via a phandle, e.g.:

        blockgpio {
                compatible = "linux,gpio-block";

                selector1 {
                        gpios = <&gpio 4 0>,
                                <&gpio 5 0>;
                };
        };

        powr at 0x20 {
                // ...

                gpios = <&selector1>;
        };


In the driver, you can get the gpio block like this:

block = gpio_block_find_by_name(of_parse_phandle(powr, "gpios", 0)->name);

(Simplified by removed error/NULL handling!)

If this turns out to be a common pattern, I can add a convenience "get"
function for this.

Roland