U-Boot not responding to pinmux

Hi Toradex,

I’m trying to change the pinmux of the following GPIO MX6_PAD_DISP0_DAT20__GPIO5_IO14 to MUX_PAD_CTRL(WEAK_PULLDOWN) in colibri_imx6.c. After change the source and updating the bootloader with run setupdate / update_uboot nothing changes to the output on the Colibri Imx6.

I’m trying to configure SODIMM 142 as pull-down at boot-time. Can you provide us some more information how to achieve this or provide some code example?

What i want is pulling the SODIMM pin to near 0 volts at boot time.

We already configured the device tree accordingly and confirmed the mux will be set while booting the kernel. We really need to set the mux as early as possible in the bootloader.

138-colibri-imx6.png

With kind regards,
Jormen Janssen

Additional information from Jormen:

We are using the GPIO MX6_PAD_DISP0_DAT20__GPIO5_IO14 (SODIMM 140) as output on our product and we must be sure it’s state is not going temporary (At U-Boot) to 3.3V.

Can you give us some more details on this matter?

Quickly checked the pulldown pinmux configuration for ‘DISP0_DAT20’ PAD at my end, it worked as expected.