* Solomon SSD1307 Framebuffer Driver

Required properties:
  - compatible: Should be "solomon,ssd1307fb-<bus>". The only supported bus for
    now is i2c.
  - reg: Should contain address of the controller on the I2C bus. Most likely
         0x3c or 0x3d
  - pwm: Should contain the pwm to use according to the OF device tree PWM
         specification [0]
  - reset-gpios: Should contain the GPIO used to reset the OLED display

Optional properties:
  - reset-active-low: Is the reset gpio is active on physical low?

[0]: Documentation/devicetree/bindings/pwm/pwm.txt

Examples:
ssd1307: oled@3c {
        compatible = "solomon,ssd1307fb-i2c";
        reg = <0x3c>;
        pwms = <&pwm 4 3000>;
        reset-gpios = <&gpio2 7>;
        reset-active-low;
};