Setting a GPIO pin as input in uboot

mike A

Genius 3490 points

Hi,

How to set a GPIO pin as input in uboot ?

Thanks And Regards,

Mike

over 11 years ago

0 Pavel Botev over 11 years ago

TI__Guru**** 170625 points

Mike,

If you want to set the GPIO in u-boot, you can do this after pinmux and with direct programming of the GPIO registers. See also the below e2e thread:

http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/716/t/146704
http://e2e.ti.com/support/embedded/linux/f/354/t/152492

Regards,
Pavel

0 mike A over 11 years ago in reply to Pavel Botev

Genius 3490 points

Hi Pavel,

All the links which you pointed set the GPIO pins as output, I need to set the GPIO pin as input. By default is the GPIO pin set as input ?

Thanks & Regards,
Mike

0 Pavel Botev over 11 years ago in reply to mike A

TI__Guru**** 170625 points

Hi Mike,

Yes, all GPIO pins are set as input by default, see GPIO_OE register in TRM.

"The GPIO_OE register is used to enable the pins output capabilities. At reset, all the GPIO related pins are configured as input and output capabilities are disabled."

Which GPIO pin exactly you want to use? Make sure nothing overwrite its default value (which is input).

BR
Pavel

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Setting a GPIO pin as input in uboot