BeagleBone Black Device tree overlay doesn't change pinmux

Question

I started working recently over a BeagleBone Black and I'm facing some problems to apply the device tree overlay to modify the pinmux in order to use some gpios. I found a lot of tutorials concerning the Device tree overlay but I'm struggling to apply the configuration. I need some help.

Here is the dts file I'm using: (BBB-CAM-00A0.dts)

/dts-v1/;
/plugin/;

/ {

compatible = "ti,beaglebone", "ti,beaglebone-black";

/* identification */
part-number = "BB-CAM";
version = "00A0";

exclusive-use =
/* the pin header uses */
        "P8.07",
        "P8.08",
        "P8.09",
        "P8.10",
        "P8.11",
        "P8.12",
        "P8.13",
        "P8.14",
        "P8.15",
        "P8.16",
        "P8.17",
        "P8.18",
        "P8.19",
        "P9.11",
        "P9.12",
        "P9.13",
        "P9.14";

fragment@0 {
        target = <&am33xx_pinmux>;
        __overlay__ {
                pinctrl_test: pinctrl_test_0_pins {
                        pinctrl-single,pins = <
                                0x090 0x07
                                0x094 0x07
                                0x09c 0x07
                                0x098 0x07
                                0x034 0x07
                                0x030 0x07
                                0x024 0x07
                                0x028 0x07
                                0x03c 0x07
                                0x038 0x07
                                0x02c 0x07
                                0x08c 0x07
                                0x020 0x07
                                0x070 0x07
                                0x078 0x07
                                0x074 0x07
                                0x048 0x07
                        >;
                };
        };
};

fragment@1 {
        target = <&ocp>;
        __overlay__ {
                        test_helper: helper {
                                status = "okay";
                                pinctrl-names = "default";
                                pinctrl-0 = <&pinctrl_test>;
                        };
                };
        };
};

None of the pins I'm using are already used from another overlay, all pins are:

pin xx (44e10xxx): (MUX UNCLAIMED) (GPIO UNCLAIMED)

I compile the dts using:

dtc -O dtb -o BBB-CAM-00A0.dtbo -b O -@ BBB-CAM-00A0.dts

Then :

cp BBB-CAM-00A0.dtbo /lib/firmware/

then:

echo BBB-CAM > /sys/devices/bone_capemgr.*/slots

At this point the overlay seems to be accepted:

 0: 54:PF---
 1: 55:PF---
 2: 56:PF---
 3: 57:PF---
 4: ff:P-O-L Bone-LT-eMMC-2G,00A0,Texas Instrument,BB-BONE-EMMC-2G
 5: ff:P-O-L Bone-Black-HDMI,00A0,Texas Instrument,BB-BONELT-HDMI
 7: ff:P-O-L Override Board Name,00A0,Override Manuf,BBB-CAM

But the pinmux seems no to change:

root@beaglebone:~/Desktop# cat $PINS |grep 890
pin 36 (44e10890) 00000037 pinctrl-single
root@beaglebone:~/Desktop# cat $PINS |grep 894
pin 37 (44e10894) 00000037 pinctrl-single
root@beaglebone:~/Desktop# cat $PINS |grep 89c
pin 39 (44e1089c) 00000037 pinctrl-single
root@beaglebone:~/Desktop# cat $PINS |grep 898
pin 38 (44e10898) 00000037 pinctrl-single
root@beaglebone:~/Desktop# cat $PINS |grep 834
pin 13 (44e10834) 00000027 pinctrl-single
root@beaglebone:~/Desktop# cat $PINS |grep 830
pin 12 (44e10830) 00000027 pinctrl-single
root@beaglebone:~/Desktop# cat $PINS |grep 824
pin 9 (44e10824) 00000027 pinctrl-single
root@beaglebone:~/Desktop# cat $PINS |grep 828
pin 10 (44e10828) 00000027 pinctrl-single
root@beaglebone:~/Desktop# cat $PINS |grep 83c
pin 15 (44e1083c) 00000027 pinctrl-single

dmesg return no relevant information.

For information, this is my unchanged kernel:

Linux beaglebone 3.8.13 #1 SMP Wed Sep 4 09:09:32 CEST 2013 armv7l GNU/Linux

I really don't know how to handle this problem, any suggestion?

Thanks a lot

"dmesg return no relevant information" -- To rectify that you could try enabling pinctrl debug, i.e CONFIG_DEBUG_PINCTRL, using menuconfig. You should look for a header file to include that would provide symbolic names for those pins instead of magic numbers. — sawdust

lcit lcit · Accepted Answer · 2014-05-15T18:05:08

Ok. problem solved, I re-installed Angstrom

BeagleBone Black Device tree overlay doesn't change pinmux

1 Answers