What kernel config options are required to gain access to the /dev/mtd* device? I am running a mainline kernel and would like access to the SPI.
Its a combination of a kernel config and device tree configuration.
I think it should work with Armbian (almost) out of the box since we include necessary patches https://github.com/armbian/build/blob/master/patch/kernel/rockchip64-current/general-rockchip-overlays.patch Just go to the armbian-config -> hardware and enable SPI
@igorp What kernel version is Raspian using? My mainline is 5.4.2.
I am running Alpine at present and would like to get it working on that.
Raspbian is OS for Raspberries while Armbian covers a selection of ARM single board computers and always uses (heavily) improved mainline kernel. Either 5.3.y or 5.4.y. In some cases Armbian provides features (Allwinner chips for example) a year before they come to mainline kernel.
No idea how you will achieve this there.
Default kernel should have support for MTD and SPI; you just have to make a device tree overlay that enables the SPI unit that the SEEPROM is connected to, and tell the kernel that there’s an SEEPROM connected to it.
You may simply be able to pluck the overlay from Armbian and drop it into your system (you will have to instruct the kernel to load the overlay, however, and if they haven’t set it up so that the chip is listed as a device in the dtbo, you’ll have to do that as well.)