About "Power Tree Changes" for L4T kernel customization

[anon54950357]

Dear Sirs

I have a question about the contents of “Power Tree Changes” in “PLATFORM_ADAPTATION_AND_BRING-UP_GUIDE (DA_08477-001) _Tegra Linux Driver Package for Jetson TX2”.

There is a description as follows.
"The Jetson P2597 baseboard has a GPIO expander. Some of the pins on the GPIO expander are used as a GPIO regulator.
One such usage is to enable vbus-2-supply which is powered using vdd_usb2_5v GPIO regulator. "

Where does the “vdd_usb2_5v GPIO regulator” shown here specifically refer to the P2597’s circuit diagram?

If anyone can understand it, I would appreciate it if you could teach me.

Best regards

[JerryChang]

hello ToruUno,

you’ll see following by checking the device tree sources. it’s pin to provide 5v for your usage.
for example,
$L4T_Sources/r32.5/Linux_for_Tegra/source/public/hardware/nvidia/platform/t18x/common/kernel-dts/t18x-common-platforms/tegra186-cvb-prod-p2597-b00-p3310-1000-a00-00.dtsi

                vdd_usb2_5v: regulator@17 {
                        compatible = "regulator-fixed-sync";
                        reg = <17>;
                        regulator-name = "vdd-usb2-5v";
                        regulator-min-microvolt = <5000000>;
                        regulator-max-microvolt = <5000000>;
                        gpio = <&gpio_i2c_0_74 0 0>;
                };

[anon54950357]

@JerryChang

vdd_usb2_5v

Hello JerryChang

Thank you for your reply.

Is it correct to interpret that “vdd_usb2_5v” in the device tree corresponds to “GPIO_EXP_P17_3V3” connected to U29 (TCA9539, I2C device address 0x74) and Pin20 on Page21of34 of the P2597 circuit diagram?

Regards

[Trumany]

Yes.