Hi Derek, > I have a Wandboard (yeah, I know, OLD Hardware) currently running a As in the imx6 based Wandboard? Which model/rev? What release of Fedora, what kernel etc? > project, and I'm trying to add some GPIO inputs to it. In previous GPIO > handling (on a different platform) I used the /sys/class/gpio interfaces > to set up the GPIO, but I've discovered this is now deprecated and removed > from Fedora. So I installed libgpiod and am trying to use it. Yes, we stopped supporting that because it was deprecated and upstream asked us to. > I'm using > https://download.technexion.com/development_resources/wandboard/wbquad-revb1-userguide.pdf > as a reference for the board layout. Specifically, on page 27, it shows > me that the JP4 header connects to GPIO3_12, GPIO3_27, GPIO6_31, CPIO1_24, > GPIO7_8, GPIO3_26, GPIO_18, and GPIO_19. > > I figure that GPIO_18 is going to be gpiochip0 line 18, and GPIO3_12 will > be gpiochip3 line 12.. Except that gpiodetect only tells me I have > gpiochip0 through gpiochip6, so I'm not sure where GPIO7_8 would get > mapped. That's the first issue I have. You'd likely need to look at the device tree and pinmappings to see how they're mapped out. > The second issue is that the kernel does not have any named mappings, so > running gpioinfo just displays generic data, like: > > gpiochip6 - 32 lines: > line 0: unnamed unused input active-high > line 1: unnamed unused input active-high > > Except, of course, looking at gpiochip3 line 12 shows me: > > gpiochip3 - 32 lines: > ... > line 12: unnamed "scl" output active-high [used open-drain] > > Which seems to imply that that GPIO3_12 is actually used for something > else -- or my mapping strategy is off. Probably a kernel device, often GPIOs are used for other things. A quick look at the dtsi for the wandboards some of the GPIOs re used for SCL/SDA pins on two of the i2c buses. The i2c1 seems to not have anything attached so I guess in on a pin header for end user use, and i2c12 has a audio codec and for the camera connector. > I'd appreciate any guidance anyone might have on this subject. If it's a iMX6 based Wandboard the guidance will be limted as the support for ARMv7 went EOL when F-36 did so I have no recollection of what kernel, libgpiod version etc was shipped there. Peter -- _______________________________________________ arm mailing list -- arm@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to arm-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/arm@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
