How to find out GPIO03 is which gpiochip and number?

Autonomous Machines Jetson & Embedded Systems Jetson Xavier NX
1

i want find out nx gpio03 is which chip, i want control /sys/class/gpio

3

hello lorilovebird,

please access pinmux spreadsheets to check that.
you may also refer to Topic 145524 for an example,
thanks

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5

however，i found the gpio is GPIO3_PCC.01 , what is CC mean?

6

hello lorilovebird,

please refer to L4T sources package for public release sources.
you may check the header file for the details of Tegra’s GPIO IDs.
for example,
$L4T_Sources/r32.4.3/Linux_for_Tegra/source/public/kernel/kernel-4.9/include/dt-bindings/gpio/tegra186-gpio.h

/* GPIOs implemented by main GPIO controller */
...
    #define TEGRA_MAIN_GPIO_PORT_CC 22

you should also check your kernel init messages for the allocation ranges for these GPIO chips, such as MAIN, AON,… etc
for example,

nvidia@nvidia-desktop:~$ dmesg | grep "registered GPIOs"
[    0.778328] gpiochip_setup_dev: registered GPIOs 288 to 511 on device: gpiochip0 (tegra-gpio)
[    0.786632] gpiochip_setup_dev: registered GPIOs 248 to 287 on device: gpiochip1 (tegra-gpio-aon)
[    0.934262] gpiochip_setup_dev: registered GPIOs 240 to 247 on device: gpiochip2 (max77620-gpio)

according to the formula below
#define TEGRA_MAIN_GPIO(port, offset) ((TEGRA_MAIN_GPIO_PORT_##port * 8) + offset)
that GPIO3_PCC.01 means port CC with offset 1, here’s the GPIO number calculation results.
i.e. 288 + ((22* 8) + 1 ) = 465

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7

It is working ,thankyou