On Wed, May 20, 2020 at 08:41:59PM +0200, Heiko Stübner wrote:

Hi Dmitry,

Am Mittwoch, 20. Mai 2020, 19:13:24 CEST schrieb Dmitry Torokhov:

quoted

Hi Johan,

On Wed, May 20, 2020 at 09:33:27AM +0200, Johan Jonker wrote:

quoted

A test with the command below gives this error:

arch/arm/boot/dts/rk3188-bqedison2qc.dt.yaml:
touchscreen@3e: reg:0:0: 56 was expected

The touchscreen chip on 'rk3188-bqedison2qc' and other BQ models
was shipped with different addresses then the binding currently allows.
Change the reg property that any address will pass.

make ARCH=arm dtbs_check
DT_SCHEMA_FILES=Documentation/devicetree/bindings/input/touchscreen/
edt-ft5x06.yaml

Signed-off-by: Johan Jonker <redacted>
---
 Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml
index 383d64a91..baa8e8f7e 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml
+++ b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml

@@ -42,7 +42,7 @@ properties:
       - focaltech,ft6236
 
   reg:
-    const: 0x38
+    maxItems: 1

Should we have a list of valid addresses instead of allowing any
address? Controllers usually have only a couple of addresses that they
support.

from what I've read, the fdt touchscreen controllers are just a generic
cpu with device-specific (or better panel-specific) firmware, which seems
to include the address as well - so it looks to be variable.

But of course that is only 2nd hand knowledge for me ;-)


But also, the i2c address is something you cannot really mess up,
either it is correct and your touchscreen works, or it isn't and and
adding entries to this list every time a new address variant pops up
feels clumsy.

Is that an Ack?

I'm fine either way. It's really only useful if there's a single 
address because with a list it could still be wrong just as any other 
data like an interrupt number could be wrong.

Rob