Re: [PATCH 5/7] drivers:input:ads7846(+tsc2046): add new common binding names, pre-calibration and flipping

From: Rob Herring
Date: Mon Nov 09 2015 - 12:31:20 EST

On Fri, Nov 06, 2015 at 04:14:47PM +0100, H. Nikolaus Schaller wrote:
> 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 <hns@xxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/input/ads7846.txt | 8 ++-

The binding change looks okay, but...

> @@ -1213,7 +1259,7 @@ static const struct ads7846_platform_data *ads7846_probe_dt(struct device *dev)
> of_property_read_u16(node, "ti,vref-mv", &pdata->vref_mv);
> pdata->keep_vref_on = of_property_read_bool(node, "ti,keep-vref-on");
> - pdata->swap_xy = of_property_read_bool(node, "ti,swap-xy");
> + pdata->swap_xy = of_property_read_bool(node, "touchscreen-swapped-x-y");

This will break with old dtb's. The driver should look for either

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