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-rw-r--r--doc/device-tree-bindings/i2c/i2c-gpio.txt37
1 files changed, 37 insertions, 0 deletions
diff --git a/doc/device-tree-bindings/i2c/i2c-gpio.txt b/doc/device-tree-bindings/i2c/i2c-gpio.txt
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+++ b/doc/device-tree-bindings/i2c/i2c-gpio.txt
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+I2C gpio device binding
+=======================
+
+Driver:
+- drivers/i2c/i2c-gpio.c
+
+Software i2c device-tree node properties:
+Required:
+* #address-cells = <1>;
+* #size-cells = <0>;
+* compatible = "i2c-gpio";
+* gpios = <sda ...>, <scl ...>;
+
+Optional:
+* i2c-gpio,delay-us = <5>;
+ The resulting transfer speed can be adjusted by setting the delay[us]
+ between gpio-toggle operations. Speed [Hz] = 1000000 / 4 * udelay[us],
+ It not defined, then default is 5us (~50KHz).
+
+Example:
+
+i2c-gpio@1 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ compatible = "i2c-gpio";
+ gpios = <&gpd1 0 GPIO_ACTIVE_HIGH>, /* SDA */
+ <&gpd1 1 GPIO_ACTIVE_HIGH>; /* CLK */
+
+ i2c-gpio,delay-us = <5>;
+
+ some_device@5 {
+ compatible = "some_device";
+ reg = <0x5>;
+ ...
+ };
+};