Documentation/devicetree/bindings/i2c/i2c-gate.txt

   1 An i2c gate is useful to e.g. reduce the digital noise for RF tuners connected
   2 to the i2c bus. Gates are similar to arbitrators in that you need to perform
   3 some kind of operation to access the i2c bus past the arbitrator/gate, but
   4 there are no competing masters to consider for gates and therefore there is
   5 no arbitration happening for gates.
   6
   7 Common i2c gate properties.
   8
   9 - i2c-gate child node
  10
  11 Required properties for the i2c-gate child node:
  12 - #address-cells = <1>;
  13 - #size-cells = <0>;
  14
  15 Optional properties for i2c-gate child node:
  16 - Child nodes conforming to i2c bus binding
  17
  18
  19 Example :
  20
  21         /*
  22            An Invensense mpu9150 at address 0x68 featuring an on-chip Asahi
  23            Kasei ak8975 compass behind a gate.
  24          */
  25
  26         mpu9150@68 {
  27                 compatible = "invensense,mpu9150";
  28                 reg = <0x68>;
  29                 interrupt-parent = <&gpio1>;
  30                 interrupts = <18 1>;
  31
  32                 i2c-gate {
  33                         #address-cells = <1>;
  34                         #size-cells = <0>;
  35
  36                         ax8975@c {
  37                                 compatible = "ak,ak8975";
  38                                 reg = <0x0c>;
  39                         };
  40                 };
  41         };