On Mon, 2016-02-01 at 21:29 +0800, Shawn Guo wrote: [snip]
> + /* STMPE811 touch screen controller */
> > + stmpe811@41 {
> > + compatible = "st,stmpe811";
>
> The compatible seems to be used by kernel without a binding document.
Indeed and looking at git logs Linus himself introduced it (;-p):
commit 5a826feedc331a2d5ced2afd832199a70b3af891
Author: Linus Walleij <[email protected]>
Date: Wed Apr 23 23:35:58 2014 +0200
Subject: mfd: stmpe: Probe properly from the Device Tree
