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How to free up emmc pin (8.24) for GPIO? #225
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That's the correct way... but note, not every "eMMC" can be disabled... Using the eMMC pins should be considered a last resort.. Regards, |
Thanks @RobertCNelson but is there a reason this would have changed with the 4.x kernel and UBOOT overlays vs the 3.8 kernel? This same BBB with 3.8.13 works. (With a different overlay of course.) |
Nope, if it worked before, i'd expect it to work now (with the exact same hardware)... I forget which model of eMMC on some boards can't be disabled.. Regards, |
I need to use P8.24 for GPIO. The default mode for this pin is 31h (mmc1_dat1)
I've modified uEnv.txt to disable eemc:
disable_uboot_overlay_emmc=1
and I see the appropriate message on boot:
uboot_overlays: uboot loading of [/lib/firmware/BB-BONE-eMMC1-01-00A0.dtbo] disa bled by /boot/uEnv.txt [disable_uboot_overlay_emmc=1]...
My overlay attempts to free up the pin with:
P8_24_pinmux { status = "disabled"; };
but I'm wondering if that is the correct way to do it for an emmc pin because I do the same thing with all of my other GPIOs and they change modes appropriately but P8.24 is still 31h and I can't take control of it. show-pins shows:
P8.24 / eMMC d1 1 fast rx up 1 mmc 1 d1
where-as my other GPIO outputs show up like this:
Is there something I'm missing?
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