-----Original Message----- From: Per Jessen <per@jessen.ch> Sent: 25 November 2019 11:43 To: Guillaume Gardet <Guillaume.Gardet@arm.com>; opensuse- arm@opensuse.org Subject: Re: [opensuse-arm] any hints for getting ds1820s to work with my nano pi neo air?
Guillaume Gardet wrote:
I picked gpio11 because it happened to be convenient for the wiring, but I don't really care which one I use. What is the easiest way of using 1-wire devices on the nanopi, without having to modify the DTB ? I'm using the Friendlycore DTB, not the one from the openSUSE Jeos image.
I fear that you need to update your DT. Not sure what is the current status of Device Tree Overlays, upstream. [snip] If device tree overlays are supported, you may just need to create a dt fragment, compile it and load it at runtime or on boot as a kernel option.
Okay, I had almost concluded that myself, thanks for confirming it. Judging by the instructions for the Raspi, it seems overlays should be fine?
On Raspberry Pi, the overlays are handled by firmware. So, this is different. RPi is different from other boards.
I'm going to go and study how to write a dt fragment for the nanopi.
My understanding is upstream kernel, as used in openSUSE, cannot apply DT overlays at runtime. You need to update your DTB, or create a fragment and merge it with your current DT. Then, use this new DTB to boot your board. Cheers, Guillaume
-- Per Jessen, Zürich (7.1°C) Member, openSUSE Heroes.
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.