On Mon, Oct 17, 2016 at 8:57 AM, H. Nikolaus Schaller hns@goldelico.com 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.
commit ed7c9870c9bc ("Input: of_touchscreen - add support for inverted / swapped axes") added another helper for parsing axis inversion and swapping and applying them to x and y coordinates.
Both helpers have been integrated to accommodate any orientation of the touch panel in relation to the LCD.
Please add the explanation of why this is a compatible change here.
A new feature is to introduce scaling the min/max ADC values to the screen size.
Sounds like a separate change.
This makes it possible to pre-calibrate the touch so that is (almost) exactly matches the LCD pixel coordinates it is glued onto. This allows to well enough operate the touch before a user space calibration step can improve the precision.
Finally, calculate_pressure has been renamed to calculate_resistance because that is what it is doing.
Signed-off-by: H. Nikolaus Schaller hns@goldelico.com
.../bindings/input/touchscreen/tsc2007.txt | 20 ++-- drivers/input/touchscreen/tsc2007.c | 120 +++++++++++++++++---- include/linux/i2c/tsc2007.h | 8 ++ 3 files changed, 118 insertions(+), 30 deletions(-)
diff --git a/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt index ec365e1..6e9fd55 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt +++ b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt @@ -6,6 +6,7 @@ Required properties:
- ti,x-plate-ohms: X-plate resistance in ohms.
Optional properties: +- generic touch screen properties: see touchscreen binding [2].
- gpios: the interrupt gpio the chip is connected to (trough the penirq pin). The penirq pin goes to low when the panel is touched. (see GPIO binding[1] for more details).
@@ -13,17 +14,20 @@ Optional properties: (see interrupt binding[0]).
- interrupts: (gpio) interrupt to which the chip is connected (see interrupt binding[0]).
-- ti,max-rt: maximum pressure. -- ti,fuzzx: specifies the absolute input fuzz x value.
- If set, it will permit noise in the data up to +- the value given to the fuzz
- parameter, that is used to filter noise from the event stream.
-- ti,fuzzy: specifies the absolute input fuzz y value. -- ti,fuzzz: specifies the absolute input fuzz z value. +- ti,max-rt: maximum pressure resistance above which samples are ignored
- (default: 4095).
+- ti,report-resistance: report resistance (no pressure = max_rt) instead
- of pressure (no pressure = 0).
+- ti,min-x: minimum value reported by X axis ADC (default 0). +- ti,max-x: maximum value reported by X axis ADC (default 4095). +- ti,min-y: minimum value reported by Y axis ADC (default 0). +- ti,max-y: maximum value reported by Y axis ADC (default 4095).
I thought these were going to be common? I think they should be.
Rob
- ti,poll-period: how much time to wait (in milliseconds) before reading again the
- values from the tsc2007.
- values from the tsc2007 (default 1).
+[2]: Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
Example: &i2c1 { @@ -35,6 +39,8 @@ Example: interrupts = <0x0 0x8>; gpios = <&gpio4 0 0>; ti,x-plate-ohms = <180>;
touchscreen-size-x = <640>;touchscreen-size-y = <480>; }; /* ... */