[PATCH v4 6/8] 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.
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.
A new feature is to introduce scaling the min/max ADC values to the screen
size.
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.
[1]: Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
Signed-off-by: H. Nikolaus Schaller
---
.../devicetree/bindings/input/ads7846.txt | 9 +++-
drivers/input/touchscreen/ads7846.c| 60 ++
2 files changed, 57 insertions(+), 12 deletions(-)
diff --git a/Documentation/devicetree/bindings/input/ads7846.txt
b/Documentation/devicetree/bindings/input/ads7846.txt
index 9fc47b0..29f91ed 100644
--- a/Documentation/devicetree/bindings/input/ads7846.txt
+++ b/Documentation/devicetree/bindings/input/ads7846.txt
@@ -26,6 +26,12 @@ 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).
@@ -33,7 +39,7 @@ Optional properties:
(ADS7846).
ti,keep-vref-on set to keep vref on for differential
measurements as well
- ti,swap-xy swap x and y axis
+ ti,swap-xy deprecated name for
touchscreen-swapped-x-y
ti,settle-delay-usecSettling time of the analog signals;
a function of Vcc and the capacitance
on the X/Y drivers. If set to non-zero,
@@ -82,6 +88,7 @@ Example for a TSC2046 chip connected to an McSPI controller
of an OMAP SoC::
pendown-gpio = < 8 0>;
vcc-supply = <_vcc3>;
+ touchscreen-swapped-x-y;
ti,x-min = /bits/ 16 <0>;
ti,x-max = /bits/ 16 <8000>;
ti,y-min = /bits/ 16 <0>;
diff --git a/drivers/input/touchscreen/ads7846.c
b/drivers/input/touchscreen/ads7846.c
index 1ce3ecb..400e421 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -34,6 +34,7 @@
#include
#include
#include
+#include
#include
/*
@@ -109,8 +110,13 @@ struct ads7846 {
u16 vref_delay_usecs;
u16 x_plate_ohms;
u16 pressure_max;
+ u16 x_min;
+ u16 x_max;
+ u16 y_min;
+ u16 y_max;
+
+ struct touchscreen_properties prop;
- boolswap_xy;
booluse_internal;
struct ads7846_packet *packet;
@@ -825,22 +831,36 @@ static void ads7846_report_state(struct ads7846 *ts)
*/
if (Rt) {
struct input_dev *input = ts->input;
+ int sx, sy;
+
+ dev_dbg(>spi->dev,
+ "Raw point(%4d,%4d), pressure (%4u)\n",
+ x, y, Rt);
+
+ /* scale ADC values to desired output range */
+ sx = (ts->prop.max_x * (x - ts->x_min))
+ / (ts->x_max - ts->x_min);
+ sy = (ts->prop.max_y * (y - ts->y_min))
+ / (ts->y_max - ts->y_min);
- if (ts->swap_xy)
- swap(x, y);
+ dev_dbg(>spi->dev,
+ "Scaled point(%4d,%4d), pressure (%4u)\n",
+ sx, sy, Rt);
+ /* report event */
if (!ts->pendown) {
input_report_key(input, BTN_TOUCH, 1);
ts->pendown = true;
dev_vdbg(>spi->dev, "DOWN\n");
}
- input_report_abs(input, ABS_X, x);
- input_report_abs(input, ABS_Y, y);
+ touchscreen_report_pos(ts->input, >prop,
+ (unsigned int)
[PATCH v4 6/8] 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.
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.
A new feature is to introduce scaling the min/max ADC values to the screen
size.
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.
[1]: Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
Signed-off-by: H. Nikolaus Schaller
---
.../devicetree/bindings/input/ads7846.txt | 9 +++-
drivers/input/touchscreen/ads7846.c| 60 ++
2 files changed, 57 insertions(+), 12 deletions(-)
diff --git a/Documentation/devicetree/bindings/input/ads7846.txt
b/Documentation/devicetree/bindings/input/ads7846.txt
index 9fc47b0..29f91ed 100644
--- a/Documentation/devicetree/bindings/input/ads7846.txt
+++ b/Documentation/devicetree/bindings/input/ads7846.txt
@@ -26,6 +26,12 @@ 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).
@@ -33,7 +39,7 @@ Optional properties:
(ADS7846).
ti,keep-vref-on set to keep vref on for differential
measurements as well
- ti,swap-xy swap x and y axis
+ ti,swap-xy deprecated name for
touchscreen-swapped-x-y
ti,settle-delay-usecSettling time of the analog signals;
a function of Vcc and the capacitance
on the X/Y drivers. If set to non-zero,
@@ -82,6 +88,7 @@ Example for a TSC2046 chip connected to an McSPI controller
of an OMAP SoC::
pendown-gpio = < 8 0>;
vcc-supply = <_vcc3>;
+ touchscreen-swapped-x-y;
ti,x-min = /bits/ 16 <0>;
ti,x-max = /bits/ 16 <8000>;
ti,y-min = /bits/ 16 <0>;
diff --git a/drivers/input/touchscreen/ads7846.c
b/drivers/input/touchscreen/ads7846.c
index 1ce3ecb..400e421 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -34,6 +34,7 @@
#include
#include
#include
+#include
#include
/*
@@ -109,8 +110,13 @@ struct ads7846 {
u16 vref_delay_usecs;
u16 x_plate_ohms;
u16 pressure_max;
+ u16 x_min;
+ u16 x_max;
+ u16 y_min;
+ u16 y_max;
+
+ struct touchscreen_properties prop;
- boolswap_xy;
booluse_internal;
struct ads7846_packet *packet;
@@ -825,22 +831,36 @@ static void ads7846_report_state(struct ads7846 *ts)
*/
if (Rt) {
struct input_dev *input = ts->input;
+ int sx, sy;
+
+ dev_dbg(>spi->dev,
+ "Raw point(%4d,%4d), pressure (%4u)\n",
+ x, y, Rt);
+
+ /* scale ADC values to desired output range */
+ sx = (ts->prop.max_x * (x - ts->x_min))
+ / (ts->x_max - ts->x_min);
+ sy = (ts->prop.max_y * (y - ts->y_min))
+ / (ts->y_max - ts->y_min);
- if (ts->swap_xy)
- swap(x, y);
+ dev_dbg(>spi->dev,
+ "Scaled point(%4d,%4d), pressure (%4u)\n",
+ sx, sy, Rt);
+ /* report event */
if (!ts->pendown) {
input_report_key(input, BTN_TOUCH, 1);
ts->pendown = true;
dev_vdbg(>spi->dev, "DOWN\n");
}
- input_report_abs(input, ABS_X, x);
- input_report_abs(input, ABS_Y, y);
+ touchscreen_report_pos(ts->input, >prop,
+ (unsigned int) sx, (unsigned int)
