From 736d16baad35a1fcbf22edac8d7d9eccae686a33 Mon Sep 17 00:00:00 2001 From: Jeff Kletsky Date: Wed, 23 Oct 2019 09:55:01 -0700 Subject: [PATCH] ath79: GL-AR300M series: Add I2C Support MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The GL-AR300M series have an internal header for I2C. Provide DTS definitions for the i2c-gpio driver. The I2C drivers; kmod-i2c-core, kmod-i2c-gpio consume ~20 kB of flash and can be loaded as modules, Default clock measured ~11.4 ms period, ~88 kHz The board has two sets of (unpopulated) headers. While facing the back of the board (looking into the Ethernet jacks), and looking from the top, the one on the left edge of the baord with four holes is the I2C header. It appears to be labeled J8 on "GL-AR300M-V1.4.0" boards. | (Patch antenna) | | | O GND | O SDA / GPIO 17 | O SCL / GPIO 16 | ⊡ 3V3 (square land) | | (Ethernet jacks) https://docs.gl-inet.com/en/3/hardware/ar300m/#pcb-pinout states "Note: I2C is not working in some early version of the router." Signed-off-by: Jeff Kletsky --- target/linux/ath79/dts/qca9531_glinet_gl-ar300m.dtsi | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/target/linux/ath79/dts/qca9531_glinet_gl-ar300m.dtsi b/target/linux/ath79/dts/qca9531_glinet_gl-ar300m.dtsi index 267f2f478fcf..b72aa65522df 100644 --- a/target/linux/ath79/dts/qca9531_glinet_gl-ar300m.dtsi +++ b/target/linux/ath79/dts/qca9531_glinet_gl-ar300m.dtsi @@ -60,6 +60,13 @@ linux,default-trigger = "phy0tpt"; }; }; + + i2c: i2c { + compatible = "i2c-gpio"; + + sda-gpios = <&gpio 17 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>; + scl-gpios = <&gpio 16 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>; + }; }; &pcie0 { -- 2.30.2