topic KPP and I2C2 in i.MX Processors

KPP and I2C2

dylanbartlett — Thu, 05 Jul 2018 12:02:03 GMT

Hi,

I'm working with an i.MX6 based SoM from Digi. I've been looking into the potential for using the KPP module to interface with a keypad we're building.

My only concern is that Digi use KEY_COL3 for I2C_2 in their module for communicating with the on-module PMIC. Does the KPP driver in Linux allow for "skipping" pins in this case?

i.e if I wanted to create a 4x4 matrix. Can I use KEY_COL0 through 2 and KEY_COL4 to create my columns? Effectively skipping KEYCOL_3 since it's being used for something else?

Thanks for the help.

Re: KPP and I2C2

igorpadykov — Fri, 06 Jul 2018 04:54:12 GMT

Hi Dylan

seems it is possible to exclude some keys from processing, one can check

documentation in linux/Documentation/devicetree/bindings/input/imx-keypad.txt

linux-2.6-imx.git - Freescale i.MX Linux Tree

Best regards
igor
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Re: KPP and I2C2

dylanbartlett — Wed, 11 Jul 2018 16:34:03 GMT

Where exactly in the documentation does it say I can do that? The only thing that tells me is to pass a pin control group. Presumably that pin group can be missing a few pins but nothing there suggest the list of kpp pins can be non-contiguous.

Re: KPP and I2C2

igorpadykov — Thu, 12 Jul 2018 00:12:37 GMT

seems some pads can be excluded from pinctrl-0 = <&pinctrl_kpp_1>

and "linux,keymap"

Regarding documentation for if list of kpp pins can be non-contiguous,

suggest to post it on kernel mail list:

Majordomo Lists at VGER.KERNEL.ORG

Best regards igor