Re: [PATCH v2 5/8] drivers:input:ads7846(+tsc2046): add new common binding names, pre-calibration and flipping

commit b98abe52fa8e ("Input: add common DT binding for touchscreens")
introduced common DT bindings for touchscreens [1] and a helper function to
parse the DT.

This has been integrated and interpretation of the inversion (flipping)
properties for the x and y axis has been added to accommodate any
orientation of the touch in relation to the LCD.

By scaling the min/max ADC values to the screen size it is now possible to
pre-calibrate the touch so that is (almost) exactly matches the LCD it is
glued onto. This allows to well enough operate the touch before a user
space calibration can improve the precision.

[1]: Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt

Signed-off-by: H. Nikolaus Schaller <redacted>
---
 .../devicetree/bindings/input/ads7846.txt          |  8 ++-
 drivers/input/touchscreen/ads7846.c                | 72 ++++++++++++++++++++--
 2 files changed, 74 insertions(+), 6 deletions(-)

diff --git a/Documentation/devicetree/bindings/input/ads7846.txt b/Documentation/devicetree/bindings/input/ads7846.txt
index df8b127..ae56355 100644
--- a/Documentation/devicetree/bindings/input/ads7846.txt
+++ b/Documentation/devicetree/bindings/input/ads7846.txt

@@ -26,12 +26,17 @@ Additional required properties:
 
 Optional properties:
 
+You can optionally specify any of the touchscreen parameters described in
+
+	Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
+
+This allows to scale, invert or swap coordinates and define the fuzz factors.
+
 	ti,vref-delay-usecs		vref supply delay in usecs, 0 for
 					external vref (u16).
 	ti,vref-mv			The VREF voltage, in millivolts (u16).
 	ti,keep-vref-on			set to keep vref on for differential
 					measurements as well
-	ti,swap-xy			swap x and y axis