topic GPIO Mapping of Android Buttons (how to remove) in i.MX Processors

GPIO Mapping of Android Buttons (how to remove)

geoffbrown — Fri, 16 May 2014 10:55:22 GMT

Hi there,

I'm developing on a freescale imx6q SABRE LITE board. Currently running Ubuntu Oneiric based on one available from Boundary Devices.

We are using the board as part of a system that includes another board (custom) that provides gpio signals to the imx6 board. The boards are connected via the J17 Android Buttons Interface gpio connector.

We only use the one pin but that appears to be mapped to the KEY_VOL_DN which is undesirable as we are using the audio output from the board. I've been hunting around for anywhere in the kernal or uboot code that defines this mapping but have been unable to find anything, does anyone know where I should be looking or what steps I need to take to either remove the mapping entirely or simple disable it?

Thanks,

Geoff

Re: GPIO Mapping of Android Buttons (how to remove)

EricNelson — Fri, 16 May 2014 14:05:36 GMT

Hi Geoffrey,

This pin-mapping is done in the board configuration, and in 3.0.35 kernels this is done in board-mx6_nitrogen6x.c:

linux-imx6/arch/arm/mach-mx6/board-mx6_nitrogen6x.c at boundary-imx_3.0.35_4.1.0 · boundarydevices/linux-imx6 · GitHub

If you remove the entry from the table, the pin won't be mapped as a keyboard input.

Re: GPIO Mapping of Android Buttons (how to remove)

geoffbrown — Fri, 16 May 2014 14:12:04 GMT

awesome, thanks :smileyhappy: