i2c: i2c-cbus-gpio: introduce driver

Add i2c driver to enable access to devices behind CBUS on Nokia Internet
Tablets.

The patch also adds CBUS I2C configuration for N8x0 which is one of the
users of this driver.

Acked-by: Felipe Balbi <balbi@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>

1 files changed, 27 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt
new file mode 100644
index 000000000000..8ce9cd2855b5
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt
@@ -0,0 +1,27 @@
+Device tree bindings for i2c-cbus-gpio driver
+
+Required properties:
+        - compatible = "i2c-cbus-gpio";
+        - gpios: clk, dat, sel
+        - #address-cells = <1>;
+        - #size-cells = <0>;
+
+Optional properties:
+        - child nodes conforming to i2c bus binding
+
+Example:
+
+i2c@0 {
+        compatible = "i2c-cbus-gpio";
+        gpios = <&gpio 66 0 /* clk */
+                 &gpio 65 0 /* dat */
+                 &gpio 64 0 /* sel */
+                >;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        retu-mfd: retu@1 {
+                compatible = "retu-mfd";
+                reg = <0x1>;
+        };
+};