I believe the pinmux gets setup in pinctrl_bind_pins() found in drivers/pinctrl.c.
pinctrl_bind_pins() gets called by really_probe(), line 291 of drivers/dd.c and then calls the gpio_of_helper_probe on line 316 or 320, so I don’t think this has anything to do with gpio-of-helper.c driver. Probably need to setup some debug statements in pinctrl_bind_pins() to see why this does not work. Regards, John > On Nov 27, 2015, at 7:25 PM, Charles Steinkuehler <[email protected]> > wrote: > > I don't have time to dig into the full details, but IIRC this has > popped up before. I don't think the gpio-of-helper driver actually > does anything (like setup the pinmux) if you're not actually > _exporting_ any gpios. But I could be wrong...it's been a while since > I crawled through the code. > > Oh, and your pinmux settings don't match the comments. If you really > want inputs with the pullup enabled, the value to use is 0x37, *NOT* > 0x17. It's important to enable the gpio receive buffer (bit 0x20) or > you won't be able to read the value on the GPIO pin (IIRC it will > always return zero). If you really want outputs and just didn't > update the comments, 0x17 is fine. > > On 11/27/2015 2:14 PM, Riley Porter wrote: >> Yes I am running: >> >> *Linux beaglebone 4.1.1-bone10 #1 Tue Jul 7 01:15:35 UTC 2015 armv7l >> GNU/Linux* >> >> I followed your instructions but still am at a loss. I was able to update >> the device tree compiler and the kernel which is now: >> >> *Linux beaglebone 4.1.13-ti-r33 #1 SMP PREEMPT Fri Nov 20 11:00:50 UTC 2015 >> armv7l GNU/Linux* >> >> Perhaps describing my exact steps might shed some light on my screw up? >> >> >> *This is the device tree I am testing with:* >> >> >> /* >>> snip for space >>> */ >>> /dts-v1/; >>> /plugin/; >>> >>> /{ >>> compatible = "ti,beaglebone", "ti,beaglebone-black"; >>> part-number = "EBB-GPIO-Example"; >>> version = "00A0"; >>> >>> fragment@0 { >>> target = <&am33xx_pinmux>; >>> >>> >>> __overlay__ { >>> ebb_example: EBB_GPIO_Example { >>> pinctrl-single,pins = < >>> >>> >>> /*============= Inputs ================*/ >>> 0x070 0x17 // P9_11 PINS$28 GPIO0_30 = 30 >>> Input Mode7 pullup >>> 0x078 0x17 // P9_12 PINS$30 GPIO1_28 = 60 >>> Input Mode7 pullup >>> 0x074 0x17 // P9_13 PINS$29 GPIO0_31 = 31 >>> Input Mode7 pullup >>> 0x048 0x17 // P9_14 PINS$18 GPIO1_18 = 50 >>> Input Mode7 pullup >>> 0x040 0x17 // P9_15 PINS$16 GPIO1_16 = 48 >>> Input Mode7 pullup >>> 0x04c 0x17 // P9_16 PINS$19 GPIO1_19 = 51 >>> Input Mode7 pullup >>> 0x15c 0x17 // P9_17 PINS$87 GPIO0_5 = 5 >>> Input Mode7 pullup >>> 0x158 0x17 // P9_18 PINS$86 GPIO0_4 = 4 >>> Input Mode7 pullup >>> >>> /* OUTPUT GPIO(mode7) 0x07 pulldown, 0x17 >>> pullup, 0x?f no pullup/down */ >>> /* INPUT GPIO(mode7) 0x27 pulldown, 0x37 >>> pullup, 0x?f no pullup/down */ >>>> ; >>> }; >>> }; >>> }; >>> >>> fragment@1 { >>> target = <&ocp>; >>> __overlay__ { >>> gpio_helper { >>> compatible = "gpio-of-helper"; >>> status = "okay"; >>> pinctrl-names = "default"; >>> pinctrl-0 = <&ebb_example>; >>> }; >>> }; >>> }; >>> }; >> >> >> >> I also removed ALL overlays from my system before doing this below. >> Here is my output from slots and a python program to get the pins i wrote: >> >> *root ~/bbb_stuff # **slots* >> >> >> >> >> * 0: PF---- -1 1: PF---- -1 2: PF---- -1 3: PF---- -1 9: P-O-L- 0 >> Override Board Name,00A0,Override Manuf,EBB-GPIO-Example* >> >> *root ~/bbb_stuff # ./getpins * >> >> >> >> *==================================================Reading Pinux >> Pins==================================================* >> >> >> >> >> >> >> >> >> *pin 16 (44e10840.0) 00000027 pinctrl-singlepin 18 (44e10848.0) 00000027 >> pinctrl-singlepin 19 (44e1084c.0) 00000027 pinctrl-singlepin 28 >> (44e10870.0) 00000017 pinctrl-singlepin 29 (44e10874.0) 00000027 >> pinctrl-singlepin 30 (44e10878.0) 00000027 pinctrl-singlepin 86 >> (44e10958.0) 00000027 pinctrl-singlepin 87 (44e1095c.0) 00000027 >> pinctrl-single* >> >> You can clearly see I have requested them all to be 0x17? >> >> *Here are the alias's I am using:* >> >> *pins='cat /sys/kernel/debug/pinctrl/44e10800.pinmux/pins'**slots='cat >> /sys/devices/platform/bone_capemgr/slots'* >> >> >> *This is the command i used to compile the dt.* >> *dtc -O dtb -o EBB-GPIO-Example-00A0.dtbo -b 0 -@ EBB-GPIO-Example.dts* >> >> *This is the command I used to install it:* >> *echo EBB-GPIO-Example-00A0 > "/sys/devices/platform/bone_capemgr/slots"* >> >> >> *This is the dmesg output after installing the overlay:* >> >> >> >> >> >> >> *[ 2629.259630] bone_capemgr bone_capemgr: part_number >> 'EBB-GPIO-Example-00A0', version 'N/A'[ 2629.259679] bone_capemgr >> bone_capemgr: slot #11: override[ 2629.259700] bone_capemgr bone_capemgr: >> Using override eeprom data at slot 11[ 2629.259722] bone_capemgr >> bone_capemgr: slot #11: 'Override Board Name,00A0,Override >> Manuf,EBB-GPIO-Example'[ 2629.271307] gpio-of-helper ocp:gpio_helper: >> ready[ 2629.271555] bone_capemgr bone_capemgr: slot #11: dtbo >> 'EBB-GPIO-Example-00A0.dtbo' loaded; overlay id #0* >> >> >> >> So any help guys would be really appreciated! I am thinking that I must be >> just doing something wrong. Perhaps the example device tree I am using is >> outdated? Would someone be willing to share with me a GPIO device tree >> that works with kernel 4.1? Also I have tried the dt builder online: >> >> http://kilobaser.com/blog/2014-07-28-beaglebone-black-devicetreeoverlay-generator#1gpiodto >> >> But this seems to not work also. Thanks again everyone. >> >> >> Riley >> >> On Thu, Nov 26, 2015 at 2:13 PM, John Syne <[email protected]> wrote: >> >>> That is strange because it seems to be working for everyone else. What is >>> your kernel version? >>> >>> If you are using kernel version 4.1 or higher, then do the following on >>> your BBB >>> >>> git clone https://github.com/RobertCNelson/bb.org-overlays.git >>> >>> Follow the instructions readme.md file. My guess is you don’t have the >>> correct Device Tree Compiler, but this repo will install the correct >>> version. >>> >>> Regards, >>> John >>> >>> >>> >>> >>> On Nov 26, 2015, at 8:35 AM, Riley Porter <[email protected]> wrote: >>> >>> Hey guys, >>> >>> I have been fighting this for a few days now. But it seems to me that no >>> matter what I do I cannot get the pinmux'ing to work when applying overlays >>> in debian. I have tried 7.8 and 8.2 and either is really different. >>> >>> I was looking around to see if I was the only one in this boat and it >>> turns out I found a post on stack exchange that describes my issue >>> perfectly. >>> >>> Unfortunately the "answer" was to install angstrom. I was hoping someone >>> on the list would have some secret answer as to why applying an overlay was >>> not changing the pinmux's? >>> >>> I would very much like to stick with debian but if the answer is go back >>> angstrom I guess I can live with that. >>> >>> Thanks >>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google Groups >>> "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send an >>> email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google Groups >>> "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send an >>> email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> > > > -- > Charles Steinkuehler > [email protected] > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
