Thanks! I had DC and Reset swapped in the overlay file. I've fixed and the display is now working! The console is displayed after bootup and libdrm modetest is able to display color bars OK.
Here is the updated dts: https://gist.github.com/pdp7/aee5664598059c9b9a9020f107957f80 Thanks, Drew On Feb 21, 2018 1:53 PM, "David Lechner" <da...@lechnology.com> wrote: > On 02/21/2018 01:18 PM, Drew Fustini wrote: > >> On Wed, Feb 21, 2018 at 11:01 AM, David Lechner <da...@lechnology.com> >> wrote: >> >>> Are you sure your phandles are correct here? They don't match the >>> comments. >>> Should it be <&gpio1 16 0> instead? >>> >>> + reset-gpios = <&gpio1 16 0>; /* >>>> reset:60 P9.12 GPIO1_28 */ >>>> >>> >>> And then <&gpio1 28 0> here? >>> >> Here is the full BB-SPIDEV1-00A0.dts: >> https://gist.github.com/pdp7/aee5664598059c9b9a9020f107957f80 >> >> I have P9.12 connected to LCD reset pin. I have P9.15 connected to >> LCD dc pin. For fbtft driver, this translated to GPIO_60 for reset >> and GPIO_48 for dc. This is based on this pinout diagram: >> https://elinux.org/File:Cape_expansion_headers.PNG >> >> For this dts file, I was trying to figure out what appropriate gpio >> phandle. I looked at this table for the P9 header: >> https://elinux.org/File:H9Pinout.PNG >> >> I believe that gpio1[16] corresponds to P9.15 which is LCD dc pin, and >> gpio1[28] corresponds to P9.12 which is LCD reset pin. >> >> My understanding of those mappings may be incorrect, so I'd appreciate >> any additional feedback. >> >> You understand correct, but I think you have swapped the values in your > device tree overlay. You say "gpio1[16] corresponds to P9.15 which is LCD > dc pin", but in the overlay, you have dc-gpios = <&gpio1 28 0>;. Likewise > "gpio1[28] corresponds to P9.12 which is LCD reset pin.", but you have > reset-gpios = <&gpio1 16 0>;. > > > -- 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 beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAPgEAj613TXf7HP87B5GMqwt_khiTm%2BQq-H%2Bj9yQMAoyAQC8Yg%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
