Linux: GPIO1 bank for Wake up

Nagamahesh Gamidi61

Intellectual 360 points

Tool/software: Linux

We are working on AM335x SOM which has wake-up and sleep mode features on Linux-4.4 kernel.

Also we came to know that, the wake-up can be done only with uart0, touch, GPIO0 bank.

But we need GPIO1 bank to wake-up the SOM.

Do you have any solution ? if not is it possible to share the firmware of GPIO0 bank.

So that we will do modifications to wake-up the SOM with GPIO1 bank.

over 8 years ago

0 Pavel Botev over 8 years ago

TI__Guru**** 170625 points

Hi Nagamahesh,

AM335x device has several low power modes (Standby, Deepsleep1, Deepsleep0). From which power mode you need to wake-up with GPIO1?

See also if the below links will be in help:

processors.wiki.ti.com/.../Linux_Core_Power_Management_User's_Guide_(v4.4)
www.ti.com/.../sprac74a.pdf
e2e.ti.com/.../550811

Regards,
Pavel

0 Nagamahesh Gamidi61 over 8 years ago in reply to Pavel Botev

Intellectual 360 points

I given te below command and it is going to sleep mode:

echo standby > /sys/power/state
[ 413.512726] PM: Syncing filesystems ... done.
[ 413.532904] Freezing user space processes ... (elapsed 0.001 seconds) done.
[ 413.541931] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[ 413.551538] Suspending console(s) (use no_console_suspend to debug)

0 Pavel Botev over 8 years ago in reply to Nagamahesh Gamidi61

TI__Guru**** 170625 points

Nagamahesh Gamidi61 said:
I given te below command and it is going to sleep mode:

echo standby > /sys/power/state

This is standby mode. You can wake-up from GPIO1. Which linux kernel version you are using?

See below e2e thread for more info how to configure GPIO1 to wake-up from standby:

Regards,
Pavel

0 Nagamahesh Gamidi61 over 8 years ago in reply to Pavel Botev

Intellectual 360 points

Hi Pavel,

Thank you very much for the reply.
I am working on Linux-4.4 kernel version.

From the link which you shared, i came to know that GPIO1 wakeup mode supported for Linux-3.2 kernel version.

So, is it possible to port the same to Linux-4.4 kernel to get wake-up support.

Regards
Nagamahesh

0 Pavel Botev over 8 years ago in reply to Nagamahesh Gamidi61

TI__Guru**** 170625 points

Nagamahesh Gamidi61 said:
From the link which you shared, i came to know that GPIO1 wakeup mode supported for Linux-3.2 kernel version.

So, is it possible to port the same to Linux-4.4 kernel to get wake-up support.

The link explains that GPIO1 wake up feature is supported for both 3.2 and 4.4 kernels, but with some differences. For 3.2 kernel you should use standby_gpio_pad_conf feature, for 4.4 kernel you should use gpio-key instance in your device tree.

Regards,
Pavel

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Linux: GPIO1 bank for Wake up