topic Re: Pinmux modification at runtime in i.MX Processors

Pinmux modification at runtime

JeromeBaron — Thu, 18 Sep 2014 11:31:44 GMT

Hi everyone,

I'm working on a platform with a iMX28 that runs Linux. I would like to know if it's allowed to change the pinmux at runtime, while in the Linux.

My goal is to use a SPI port, program a device, then change those IO to GPIO after the programmation.

Can I do this? How?

Regards,

Jerome

Re: Pinmux modification at runtime

igorpadykov — Thu, 18 Sep 2014 23:31:44 GMT

Hi Jerome

seems not, since linux spi driver will own pins. To rmmod driver one needs

to be administrator with root permissions.

Best regards

igor

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Re: Pinmux modification at runtime

JeromeBaron — Fri, 19 Sep 2014 17:28:35 GMT

It appears the answer is a simple memory write to the CPU registers. I have found a small application(imxregs) in amadeus distribution to access those registers.