AM1808: Problem with two GPIOs

Niclas Knuts

Other Parts Discussed in Thread: AM1808

Hi,

I have a custom made AM1808 board that works very fine, however it has two interesting problems, two GPIOs are not working, the GPIO numbers are:

GPIO6[13] (GPIO Pin 110, R17) and GPIO2[4] (GPIO Pin 37, A9)

I have verified that they are connected to the correct pins (according to AM1808 datasheet), however I cannot export them in Linux /sys/, all the pin mappings seem to be fine, that is I have defined the pins to be GPIOs. I have also verified that GPIO6[12], GPIO6[14] and GPIO2[3], GPIO2[5] works as expected and can be exported in /sys/.

What could be the reason for this behaviour?

Best Regards.

Niclas

over 14 years ago

0 Norman Wong over 14 years ago

Guru 26430 points

Not sure if this will help. Coincidentally those two pins are used by USB 1.1. You might have to comment out the configuration of those pins in your board.c file. I think that in your case that file would be board-da850-evm.c. Look for ON_BD_USB_DRV, ON_BD_USB_OVC and da850_evm_usb11_pins. Perhaps you have to unconfig the USB 1.1 OHCI driver in the kernel as well.

0 Niclas Knuts over 14 years ago in reply to Norman Wong

Intellectual 655 points

That does make sense. I am using USB OTG, but not USB 1.1 OHCI, so I will try to disable OHCI and let you know how it went.

Best Regards,

Niclas

0 Niclas Knuts over 14 years ago in reply to Niclas Knuts

Intellectual 655 points

Ok, I got it to work, the GPIOs didn't work because they were configured as OHCI Bluetooth. Thanks for the help!

Niclas

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AM1808: Problem with two GPIOs