rampis: HLK-RM04 - Setup I2C as GPIO
authorJohn Crispin <john@openwrt.org>
Mon, 8 Feb 2016 08:26:19 +0000 (08:26 +0000)
committerJohn Crispin <john@openwrt.org>
Mon, 8 Feb 2016 08:26:19 +0000 (08:26 +0000)
The I2C function of the RT5350 SoC on the HLK-RM04 is used for GPIO1 and GPIO2.

Take note that the I2C_SD pin is GPIO1 on the RT5350 and is exposed on the HLK-RM04 as GPIO0
Likewise the I2C_SCLK pin is GPIO2 on the RT5350 and is exposed on the HLK-RM04 as GPIO1

 group   mode 1    mode 2   hlk-rm04 pin & export
  i2c    i2c_sd    gpio1   (pin 8, hlk-rm04:gpio0)
  i2c    i2c_sclk  gpio2   (pin 9, hlk-rm04:gpio1)

reference:
  http://www.hlktech.net/product_detail.php?ProId=39
  http://cdn.sparkfun.com/datasheets/Wireless/WiFi/RT5350.pdf

Signed-off-by: John Clark <inindev@gmail.com>
SVN-Revision: 48664

target/linux/ramips/dts/HLKRM04.dts

index 5f43642..713b51f 100644 (file)
@@ -60,7 +60,7 @@
        pinctrl {
                state_default: pinctrl0 {
                        gpio {
-                               ralink,group = "jtag";
+                               ralink,group = "i2c", "jtag";
                                ralink,function = "gpio";
                        };
                };
                status = "okay";
        };
 
+       gpio-export {
+               compatible = "gpio-export";
+               #size-cells = <0>;
+
+               /* I2C */
+               gpio1 {
+                       /* I2C_I2C_SD */
+                       gpio-export,name = "hlk-rm04:gpio0";
+                       gpio-export,direction_may_change = <1>;
+                       gpios = <&gpio0 1 0>;
+               };
+               gpio2 {
+                       /* I2C_I2C_SCLK */
+                       gpio-export,name = "hlk-rm04:gpio1";
+                       gpio-export,direction_may_change = <1>;
+                       gpios = <&gpio0 2 0>;
+               };
+       };
+
        gpio-keys-polled {
                compatible = "gpio-keys-polled";
                #address-cells = <1>;