Processor Expert SoftwareのトピックRe: configure GPIO as input in imx8mp

configure GPIO as input in imx8mp

DEEPIKA19 — Tue, 13 Dec 2022 05:45:19 GMT

Hi team

I would like to use the GPIO5_IO25 as a input pin in our design. By default when exported from sysfs I am getting the following value.

root@root:/sys/class/gpio/gpio153# cat direction

root@root:/sys/class/gpio/gpio153# cat value

The GPIO5_IO05 is connected to a 10k pullup but the value is 0. Please could someone suggest me on how to debug this. Should any dts changes be added for this?

Regards,

Deepika

Re: configure GPIO as input in imx8mp

Dhruvit — Wed, 14 Dec 2022 04:19:37 GMT

Hi @DEEPIKA19,

In the case of the GPIO5_IO25, it should be mentioned that when a GPIO is exported in the sysfs, by default, the direction of the GPIO is set as "input," and the value is set to "zero." The processor itself drives the voltage level of that particular GPIO.

For the GPIO5_IO05, please confirm the voltage at the processor side of the GPIO5_IO05 before and after exporting the GPIO.

And also, please confirm if the GPIO5_IO05 is not used in the device tree by any other peripheral.

Thanks & Regards,
Dhruvit.

Re: configure GPIO as input in imx8mp

DEEPIKA19 — Wed, 28 Dec 2022 07:39:05 GMT

hi @Dhruvit ,

Thanks for your reply.

Regards,

Deepika

Re: configure GPIO as input in imx8mp

Dhruvit — Fri, 06 Jan 2023 07:54:34 GMT

Hi @DEEPIKA19

If this issue is resolved, then Can I mark this case to close state?

Thanks & Regards

Dhruvit Vasavda

Re: configure GPIO as input in imx8mp

DEEPIKA19 — Mon, 09 Jan 2023 07:13:38 GMT

hi @Dhruvit ,

The issue is not resolved.

I tried to add device_init_wakeup(&client->dev, 1) as suggested but i am still facing the the same issue.

Regards,

Deepika

Re: configure GPIO as input in imx8mp

DEEPIKA19 — Tue, 10 Jan 2023 07:40:54 GMT

Thanks for your support @Dhruvit ,

The issues is resolved making driver change in reference with similar touch drivers .

Regards,

Deepika