On the Beaglebone Black Rev C, debian 9.3, 4.4.68-ti-r110, the device tree sources /opt/source/bb.org-overlays/src/arm/cape_universal-00A0.dts show that when P9_24 and P9_26 are set up as pruin, the pad control should be:
P9_24_pruin_pin: pinmux_P9_24_pruin_pin {
pinctrl-single,pins = <0x184 0x36>; }; / Mode 6, Pull-Up, RxActive /
and
P9_26_pruin_pin: pinmux_P9_26_pruin_pin {
pinctrl-single,pins = <0x180 0x36>; }; / Mode 6, Pull-Up, RxActive */
The command line: "config-pin p9.24 pruin && config-pin -q p9.24" shows "P9_24 Mode: pruin"
however, the command "grep 984 pins" shows "pin 97 (44e10984.0) 00000026 pinctrl-single" this should be 36 rather than 26 i.e. it shows pull-down rather than pull-up.
The results are similar for p9.26.
Decompiling the corresponding dtbo(s), show that the 26 is the correct(?) value.
Either the dts or dtb(s) should be modified to bring them into sync.
My preference, fwiw, is the pull-up configuration to give two pruin pins a pullup input rather than all pull-downs.
On the Beaglebone Black Rev C, debian 9.3, 4.4.68-ti-r110, the device tree sources /opt/source/bb.org-overlays/src/arm/cape_universal-00A0.dts show that when P9_24 and P9_26 are set up as pruin, the pad control should be: P9_24_pruin_pin: pinmux_P9_24_pruin_pin { pinctrl-single,pins = <0x184 0x36>; }; / Mode 6, Pull-Up, RxActive / and P9_26_pruin_pin: pinmux_P9_26_pruin_pin { pinctrl-single,pins = <0x180 0x36>; }; / Mode 6, Pull-Up, RxActive */ The command line: "config-pin p9.24 pruin && config-pin -q p9.24" shows "P9_24 Mode: pruin" however, the command "grep 984 pins" shows "pin 97 (44e10984.0) 00000026 pinctrl-single" this should be 36 rather than 26 i.e. it shows pull-down rather than pull-up. The results are similar for p9.26. Decompiling the corresponding dtbo(s), show that the 26 is the correct(?) value. Either the dts or dtb(s) should be modified to bring them into sync. My preference, fwiw, is the pull-up configuration to give two pruin pins a pullup input rather than all pull-downs.