How to set imx6dl board gpio default low level in uboot once power on

cancel
Showing results for 
Search instead for 
Did you mean: 

How to set imx6dl board gpio default low level in uboot once power on

Jump to solution
950 Views
mrleo
Contributor IV

HI,all

I  found that imx6 some gpio default is output high level once power on.

example:GPIO_2(GPIO_1_2)),NANDF_D5(GPIO_2_5)

My custom imx6dl board is used these two gpio  to control  lcd power and lcd reset.

These two gpio are default high level.

If I want these two gpio are default low level,what should I do?

Who can give me a help? Or give me an advices?

Thanks,

Leo

0 Kudos
1 Solution
528 Views
igorpadykov
NXP TechSupport
NXP TechSupport

Hi Leo

if one uses plugin mode, this can be added to dcd header.

Otherwise, for uboot 2009 this may be lowlevel_init.S,

for later uboot versions seems in miscellaneous functions

like board_xx_init_yy in   ..freescale/mx6sabresd/mx6sabresd.c

Best regards

igor

-----------------------------------------------------------------------------------------------------------------------

Note: If this post answers your question, please click the Correct Answer button. Thank you!

-----------------------------------------------------------------------------------------------------------------------

View solution in original post

0 Kudos
3 Replies
529 Views
igorpadykov
NXP TechSupport
NXP TechSupport

Hi Leo

if one uses plugin mode, this can be added to dcd header.

Otherwise, for uboot 2009 this may be lowlevel_init.S,

for later uboot versions seems in miscellaneous functions

like board_xx_init_yy in   ..freescale/mx6sabresd/mx6sabresd.c

Best regards

igor

-----------------------------------------------------------------------------------------------------------------------

Note: If this post answers your question, please click the Correct Answer button. Thank you!

-----------------------------------------------------------------------------------------------------------------------

0 Kudos
528 Views
mrleo
Contributor IV

Hi igorpadyov,

I have added to uboot 2009 in lowlevel_init.S( lowlevel_init below,befor inv_dcache).

But it will have a very shorter time high level then (in lowlevel_init.S set to low level) low level once power on.

Thanks,

Leo

Re: How to set imx6dl board gpio default low level in uboot once power on
0 Kudos
528 Views
igorpadykov
NXP TechSupport
NXP TechSupport

Hi Leo

default pad state after reset is not possible to change, so

there always will be short time until software change pin state.

This is inevitable.

~igor

0 Kudos