tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1I2C bus that tunnels through the ChromeOS EC (cros-ec)
2======================================================
3On some ChromeOS board designs we've got a connection to the EC (embedded
4controller) but no direct connection to some devices on the other side of
5the EC (like a battery and PMIC). To get access to those devices we need
6to tunnel our i2c commands through the EC.
7
8The node for this device should be under a cros-ec node like google,cros-ec-spi
9or google,cros-ec-i2c.
10
11
12Required properties:
13- compatible: google,cros-ec-i2c-tunnel
14- google,remote-bus: The EC bus we'd like to talk to.
15
16Optional child nodes:
17- One node per I2C device connected to the tunnelled I2C bus.
18
19
20Example:
21 cros-ec@0 {
22 compatible = "google,cros-ec-spi";
23
24 ...
25
26 i2c-tunnel {
27 compatible = "google,cros-ec-i2c-tunnel";
28 #address-cells = <1>;
29 #size-cells = <0>;
30
31 google,remote-bus = <0>;
32
33 battery: sbs-battery@b {
34 compatible = "sbs,sbs-battery";
35 reg = <0xb>;
36 sbs,poll-retry-count = <1>;
37 };
38 };
39 }