AM6548: API guide for GPIO driver of processor SDK Linux

Hi, Keerthy

Sorry for my late reply.

Thank you for your reply.

I have two questions about GPIO Driver.

Q1

According to above URL, I looked for the documentation about GPIO driver and found "gpio.txt" in /doc/device-tree-bindings/gpio.

I understand that this text indicates how to create API for GPIO.

Do I have to make APIs for GPIO driver ?

Or could you tell me if the APIs for GPIO driver are prepared ?

Q2

I got "gpio-davici.c".

I would like to enable a GPIO pin interrupt, and read/write the value of GPIO pin.

In gpio-davinci.c, I found functions for read/write but could not find the function to enable a GPIO pin interrupt.

I also want to understand the meanings of the arguments and the return value of the functions in gpio-davinci.c.

Could you tell me where to find the documents that describe about the meanings of these and where to find the function to enable a GPIO pin interrupt ?

Thanks and regards,

Naoya Kimura

Hi,

If you are looking for generic GPIO understanding: https://www.kernel.org/doc/html/v4.19/driver-api/gpio/index.html

Driver interface: https://www.kernel.org/doc/html/latest/driver-api/gpio/driver.html

Hope that helps.

Best Regards,
Keerthy

Hi Keerthy,

Thank you for your reply.

I understand that generic GPIO interface(gpio_chip) can enable interrupt and read/write the value of GPIO pin.

I have a additional quesetion about the setting for GPIO pin.

Q1

Currently, I would like to know which GPIO pin I can use in SDK linux.

Could you tell me which GPIO pin of TMDX654IDKEVM I can use in the environment of generic GPIO interface?

If there is a document that describe about it, could you tell me where to find the document ?

Thanks and regards,

Naoya Kimura 

Hi Keerthy,

Thank you for your quick reply.

I understand how to use sysfs commands for GPIO.

In order to understand more deeply, I have a additional question.

Q1

I want to learn more about the settings for the pinmux.

According to below thread, the data manual for am6548 indicates what kind of GPIO pin I can use for the settings.

e2e.ti.com/.../tmdx654idkevm-gpios-in-linux

Is my understanding correct ?

If not, could you tell me where to find the documents that describe about GPIO pin which I can use ?

Thanks and regards,

Naoya Kimura