Re: [PATCH] spi: spidev: Add compatible for external SPI ports on Kontron boards

From: Frieder Schrempf
Date: Thu Jul 02 2020 - 12:24:57 EST


On 02.07.20 17:07, Mark Brown wrote:
On Thu, Jul 02, 2020 at 04:46:09PM +0200, Frieder Schrempf wrote:

My intention is to use the spidev driver in the default board DT for an
interface that is routed to an extension connector and has no dedicated
slave device attached onboard. So users can attach sensors, etc. with
userspace drivers without touching the kernel or DT.

The expected way of doing this is to describe whatever was attached via
DT when it's attached - the device is what has the compatible, not some
connector in the middle of the connection. The way you've got things
set up if the device has a driver then they won't be able to instantiate
the driver.

Ok thanks, got it. I will remove the spi device from the board DT and use an overlay if required. Now I got a reason to learn writing DT overlays ;)