[PATCH v1 2/4] ARM: dts: Add i2c-arbitrator bus for exynos5250-snow
Stephen Warren
swarren at wwwdotorg.org
Wed Feb 13 16:04:18 EST 2013
On 02/13/2013 11:02 AM, Doug Anderson wrote:
> We need to use the i2c-arbitrator to talk to any of the devices on i2c
> bus 4 on exynos5250-snow so that we don't confuse the embedded
> controller (EC). Add the i2c-arbitrator to the device tree. As we
> add future devices (keyboard, sbs, tps65090) we'll add them on top of
> this.
>
> The arbitrated bus is numbered 104 simply as a convenience to make it
> easier for people poking around to guess that it might have something
> to do with the physical bus 4.
>
> The addition is split between the cros5250-common and the snow device
> tree file since not all cros5250-class devices use arbitration.
> diff --git a/arch/arm/boot/dts/cros5250-common.dtsi b/arch/arm/boot/dts/cros5250-common.dtsi
> i2c at 12CA0000 {
> - status = "disabled";
> + samsung,i2c-sda-delay = <100>;
> + samsung,i2c-max-bus-freq = <66000>;
Shouldn't that use the standard clock-frequency property?
> diff --git a/arch/arm/boot/dts/exynos5250-snow.dts b/arch/arm/boot/dts/exynos5250-snow.dts
> + i2c-arbitrator {
> + compatible = "i2c-arbitrator";
> + #address-cells = <1>;
> + #size-cells = <0>;
> + /* Use ID 104 as a hint that we're on physical bus 4 */
> + i2c_104: i2c at 0 {
Does something use that hint? It sounds a little odd.
More information about the linux-arm-kernel
mailing list