HID: wacom: Report ABS_TILT_{X,Y} as signed values

PATCH In review Jason Gerecke 3 participants 4 messages Nov 19, 2014 – Nov 21, 2014

Subsystems (2)

HID HID wacom driver

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Jason Gerecke

author

2014-11-19 00:50 UTC #0 lore raw

PATCH 1/2 HID: wacom: Report ABS_TILT_{X,Y} as signed values

Centers the ABS_TILT_{X,Y} axes so that a value of zero is reported when the pen is vertical. Combined with resolution information in the next patch, this makes it possible for userspace to calculate the pen angle without needing hardware-specific knowledge. The xf86-input-wacom driver was updated to support signed tilt values in late-2012 (2f2acec).

Signed-off-by Jason Gerecke <[email protected]>

---
 drivers/hid/wacom_wac.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

drivers/hid/wacom_wac.c +8 -8

index 8a83da9..525b648 100644
@@ -600,8 +600,8 @@ static void wacom_intuos_general(struct wacom_wac *wacom)
 		}
 		input_report_abs(input, ABS_PRESSURE, t);
 		input_report_abs(input, ABS_TILT_X,
-				((data[7] << 1) & 0x7e) | (data[8] >> 7));
-		input_report_abs(input, ABS_TILT_Y, data[8] & 0x7f);
+				 (((data[7] << 1) & 0x7e) | (data[8] >> 7)) - 64);
+		input_report_abs(input, ABS_TILT_Y, (data[8] & 0x7f) - 64);
 		input_report_key(input, BTN_STYLUS, data[1] & 2);
 		input_report_key(input, BTN_STYLUS2, data[1] & 4);
 		input_report_key(input, BTN_TOUCH, t > 10);

@@ -612,8 +612,8 @@ static void wacom_intuos_general(struct wacom_wac *wacom)
 		input_report_abs(input, ABS_WHEEL,
 				(data[6] << 2) | ((data[7] >> 6) & 3));
 		input_report_abs(input, ABS_TILT_X,
-				((data[7] << 1) & 0x7e) | (data[8] >> 7));
-		input_report_abs(input, ABS_TILT_Y, data[8] & 0x7f);
+				 (((data[7] << 1) & 0x7e) | (data[8] >> 7)) - 64);
+		input_report_abs(input, ABS_TILT_Y, (data[8] & 0x7f) - 64);
 	}
 }

@@ -915,8 +915,8 @@ static int wacom_intuos_irq(struct wacom_wac *wacom)
 				input_report_key(input, BTN_EXTRA,  data[6] & 0x10);
 
 				input_report_abs(input, ABS_TILT_X,
-					((data[7] << 1) & 0x7e) | (data[8] >> 7));
-				input_report_abs(input, ABS_TILT_Y, data[8] & 0x7f);
+					(((data[7] << 1) & 0x7e) | (data[8] >> 7)) - 64);
+				input_report_abs(input, ABS_TILT_Y, (data[8] & 0x7f) - 64);
 			} else {
 				/* 2D mouse packet */
 				input_report_key(input, BTN_LEFT,   data[8] & 0x04);

@@ -1926,8 +1926,8 @@ static void wacom_setup_cintiq(struct wacom_wac *wacom_wac)
 	input_set_abs_params(input_dev, ABS_DISTANCE,
 			     0, wacom_wac->features.distance_max, 0, 0);
 	input_set_abs_params(input_dev, ABS_WHEEL, 0, 1023, 0, 0);
-	input_set_abs_params(input_dev, ABS_TILT_X, 0, 127, 0, 0);
-	input_set_abs_params(input_dev, ABS_TILT_Y, 0, 127, 0, 0);
+	input_set_abs_params(input_dev, ABS_TILT_X, -64, 63, 0, 0);
+	input_set_abs_params(input_dev, ABS_TILT_Y, -64, 63, 0, 0);
 }
 
 static void wacom_setup_intuos(struct wacom_wac *wacom_wac)

Signature · 1 line

2.1.3

Jason Gerecke

author

2014-11-19 00:50 UTC #1 lore raw

PATCH 2/2 HID: wacom: Add angular resolution data to some ABS axes

Provide the resolution of several angular axes (tilt, pen rotation, puck rotation) to userspace. Because these values are natively degree-based, we need to convert them to into units/radian as required by the input_absinfo struct. To ensure wraparound behaves properly for the rotation axes, the converted value was rounded up rather than rounded nearest.

Notably, the touchring axes (ABS_WHEEL and ABS_THROTTLE) are left without a a declared resolution because the their low resolution cannot be accurately represented (the worst-case rounding-induced error would be ~16 degrees). Pre-scaling the values and range by at least 10x would reduce the error in the resolution to acceptable levels, but the xf86-input-wacom driver is not able to use pre-scaled values for these axes at this time.

Signed-off-by Jason Gerecke <[email protected]>

---
 drivers/hid/wacom_wac.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

drivers/hid/wacom_wac.c +10 -0

index 525b648..5833731 100644
@@ -1927,7 +1927,9 @@ static void wacom_setup_cintiq(struct wacom_wac *wacom_wac)
 			     0, wacom_wac->features.distance_max, 0, 0);
 	input_set_abs_params(input_dev, ABS_WHEEL, 0, 1023, 0, 0);
 	input_set_abs_params(input_dev, ABS_TILT_X, -64, 63, 0, 0);
+	input_abs_set_res(input_dev, ABS_TILT_X, 57);
 	input_set_abs_params(input_dev, ABS_TILT_Y, -64, 63, 0, 0);
+	input_abs_set_res(input_dev, ABS_TILT_Y, 57);
 }
 
 static void wacom_setup_intuos(struct wacom_wac *wacom_wac)

@@ -1947,6 +1949,7 @@ static void wacom_setup_intuos(struct wacom_wac *wacom_wac)
 	__set_bit(BTN_TOOL_LENS, input_dev->keybit);
 
 	input_set_abs_params(input_dev, ABS_RZ, -900, 899, 0, 0);
+	input_abs_set_res(input_dev, ABS_RZ, 287);
 	input_set_abs_params(input_dev, ABS_THROTTLE, -1023, 1023, 0, 0);
 }

@@ -2092,6 +2095,7 @@ int wacom_setup_input_capabilities(struct input_dev *input_dev,
 
 	case WACOM_24HD:
 		input_set_abs_params(input_dev, ABS_Z, -900, 899, 0, 0);
+		input_abs_set_res(input_dev, ABS_Z, 287);
 		input_set_abs_params(input_dev, ABS_THROTTLE, 0, 71, 0, 0);
 		/* fall through */

@@ -2106,6 +2110,7 @@ int wacom_setup_input_capabilities(struct input_dev *input_dev,
 	case WACOM_BEE:
 	case CINTIQ:
 		input_set_abs_params(input_dev, ABS_Z, -900, 899, 0, 0);
+		input_abs_set_res(input_dev, ABS_Z, 287);
 
 		__set_bit(INPUT_PROP_DIRECT, input_dev->propbit);

@@ -2114,6 +2119,7 @@ int wacom_setup_input_capabilities(struct input_dev *input_dev,
 
 	case WACOM_13HD:
 		input_set_abs_params(input_dev, ABS_Z, -900, 899, 0, 0);
+		input_abs_set_res(input_dev, ABS_Z, 287);
 		__set_bit(INPUT_PROP_DIRECT, input_dev->propbit);
 		wacom_setup_cintiq(wacom_wac);
 		break;

@@ -2122,6 +2128,7 @@ int wacom_setup_input_capabilities(struct input_dev *input_dev,
 	case INTUOS3L:
 	case INTUOS3S:
 		input_set_abs_params(input_dev, ABS_Z, -900, 899, 0, 0);
+		input_abs_set_res(input_dev, ABS_Z, 287);
 		/* fall through */
 
 	case INTUOS:

@@ -2144,6 +2151,7 @@ int wacom_setup_input_capabilities(struct input_dev *input_dev,
 					      0, 0);
 
 			input_set_abs_params(input_dev, ABS_Z, -900, 899, 0, 0);
+			input_abs_set_res(input_dev, ABS_Z, 287);
 
 			wacom_setup_intuos(wacom_wac);
 		} else if (features->device_type == BTN_TOOL_FINGER) {

@@ -2162,6 +2170,7 @@ int wacom_setup_input_capabilities(struct input_dev *input_dev,
 	case INTUOS4L:
 	case INTUOS4S:
 		input_set_abs_params(input_dev, ABS_Z, -900, 899, 0, 0);
+		input_abs_set_res(input_dev, ABS_Z, 287);
 		wacom_setup_intuos(wacom_wac);
 
 		__set_bit(INPUT_PROP_POINTER, input_dev->propbit);

@@ -2261,6 +2270,7 @@ int wacom_setup_input_capabilities(struct input_dev *input_dev,
 
 	case CINTIQ_HYBRID:
 		input_set_abs_params(input_dev, ABS_Z, -900, 899, 0, 0);
+		input_abs_set_res(input_dev, ABS_Z, 287);
 		__set_bit(INPUT_PROP_DIRECT, input_dev->propbit);
 
 		wacom_setup_cintiq(wacom_wac);

Signature · 1 line

2.1.3

Ping Cheng

Reviewed-by on v1 1/2

2014-11-21 19:55 UTC #2 lore raw

In reply to Jason Gerecke

Quoted 7 lines · Jason Gerecke

Centers the ABS_TILT_{X,Y} axes so that a value of zero is reported when the pen is vertical. Combined with resolution information in the next patch, this makes it possible for userspace to calculate the pen angle without needing hardware-specific knowledge. The xf86-input-wacom driver was updated to support signed tilt values in late-2012 (2f2acec).
Signed-off-by Jason Gerecke <[email protected]>

Reviewed-by Ping Cheng <[email protected]> for the series.

Thanks Jason for the patches,

Ping

Quoted 55 lines

---
 drivers/hid/wacom_wac.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

drivers/hid/wacom_wac.c +8 -9

index 8a83da9..525b648 100644
@@ -600,8 +600,8 @@ static void wacom_intuos_general(struct wacom_wac *wacom)
                }
                input_report_abs(input, ABS_PRESSURE, t);
                input_report_abs(input, ABS_TILT_X,
-                               ((data[7] << 1) & 0x7e) | (data[8] >> 7));
-               input_report_abs(input, ABS_TILT_Y, data[8] & 0x7f);
+                                (((data[7] << 1) & 0x7e) | (data[8] >> 7)) - 64);
+               input_report_abs(input, ABS_TILT_Y, (data[8] & 0x7f) - 64);
                input_report_key(input, BTN_STYLUS, data[1] & 2);
                input_report_key(input, BTN_STYLUS2, data[1] & 4);
                input_report_key(input, BTN_TOUCH, t > 10);

@@ -612,8 +612,8 @@ static void wacom_intuos_general(struct wacom_wac *wacom)
                input_report_abs(input, ABS_WHEEL,
                                (data[6] << 2) | ((data[7] >> 6) & 3));
                input_report_abs(input, ABS_TILT_X,
-                               ((data[7] << 1) & 0x7e) | (data[8] >> 7));
-               input_report_abs(input, ABS_TILT_Y, data[8] & 0x7f);
+                                (((data[7] << 1) & 0x7e) | (data[8] >> 7)) - 64);
+               input_report_abs(input, ABS_TILT_Y, (data[8] & 0x7f) - 64);
        }
 }

@@ -915,8 +915,8 @@ static int wacom_intuos_irq(struct wacom_wac *wacom)
                                input_report_key(input, BTN_EXTRA,  data[6] & 0x10);
 
                                input_report_abs(input, ABS_TILT_X,
-                                       ((data[7] << 1) & 0x7e) | (data[8] >> 7));
-                               input_report_abs(input, ABS_TILT_Y, data[8] & 0x7f);
+                                       (((data[7] << 1) & 0x7e) | (data[8] >> 7)) - 64);
+                               input_report_abs(input, ABS_TILT_Y, (data[8] & 0x7f) - 64);
                        } else {
                                /* 2D mouse packet */
                                input_report_key(input, BTN_LEFT,   data[8] & 0x04);

@@ -1926,8 +1926,8 @@ static void wacom_setup_cintiq(struct wacom_wac *wacom_wac)
        input_set_abs_params(input_dev, ABS_DISTANCE,
                             0, wacom_wac->features.distance_max, 0, 0);
        input_set_abs_params(input_dev, ABS_WHEEL, 0, 1023, 0, 0);
-       input_set_abs_params(input_dev, ABS_TILT_X, 0, 127, 0, 0);
-       input_set_abs_params(input_dev, ABS_TILT_Y, 0, 127, 0, 0);
+       input_set_abs_params(input_dev, ABS_TILT_X, -64, 63, 0, 0);
+       input_set_abs_params(input_dev, ABS_TILT_Y, -64, 63, 0, 0);
 }
 
 static void wacom_setup_intuos(struct wacom_wac *wacom_wac)
--

2.1.3

Jiri Kosina

2014-11-21 21:41 UTC #3 lore raw

Quoted 10 lines · Ping Cheng

Quoted 7 lines · Jason Gerecke
Centers the ABS_TILT_{X,Y} axes so that a value of zero is reported when the pen is vertical. Combined with resolution information in the next patch, this makes it possible for userspace to calculate the pen angle without needing hardware-specific knowledge. The xf86-input-wacom driver was updated to support signed tilt values in late-2012 (2f2acec).
Signed-off-by Jason Gerecke <[email protected]>
Reviewed-by Ping Cheng <[email protected]> for the series.

Series now queued in for-3.19/wacom. Thanks,

Signature · 2 lines

Jiri Kosina
SUSE Labs