How to expose /sys/class/gpio/gpioX/power/wakeup

Nolan Replogle

Hello,

I am trying to enable GPIO interrupt wakeups from standby mode using linux 3.12.10 (sitara 7.0 sdk) on the beagle bone black. I can get the GPIOs to interrupt just fine, but when I try to enable wakeup by doing:

echo enabled > /sys/class/gpio/gpioX/power/wakeup [where X is any GPIO number] I discover that wakeup is not exposed/supported.

I know the GPIO driver for am335x supports this, so I am either thinking that my .config file or .dts file is missing something.

Any insight is much appreciated.

Thanks,

Nolan

over 11 years ago

0 Titusrathinaraj Stalin over 11 years ago

TI__Guru** 116100 points

Hi Nolan,

I hope you don't want to enable any support in kernel.

Please make sure that you have "debugfs" support in kernel.

Refer the following TI wiki.

http://processors.wiki.ti.com/index.php/AM335x_Power_Management_Standby_User%27s_Guide#GPIO_wakeup

0 Nolan Replogle over 11 years ago in reply to Titusrathinaraj Stalin

Prodigy 180 points

Thank you for replying.

I am actually unable to locate /debugfs/omap_mux/board/ as well, even though I have CONFIG_DEBUG_FS enabled.

But surely I should not have to mount debugfs just to enable this feature? That would be ideal.

I know other mpus and boards enable wakeup in the .dts, but I am not sure how to do this.

Thanks,

Nolan

0 Miroslav Kiradzhiyski XID over 11 years ago in reply to Nolan Replogle

TI__Mastermind 25235 points

Hi Nolan,

I'm sorry, but the omap_mux folder doesn't exist anymore in the debugfs. It was present in kernel 3.2, but since moving to the new 3.12 kernel, it was removed, because device tree overlays can be used instead. For more information about device tree overlays, please check the following link: http://elinux.org/BeagleBone_and_the_3.8_Kernel#Cape_Manager_and_Device_Tree_Overlays

Best regards,
Miroslav

Processors

Processors forum

How to expose /sys/class/gpio/gpioX/power/wakeup