tablet: use the AttrPressureRange quirk for tablets too

The Aiptek 8000U has a pressure offset above our default (%5) but no
meaningful way of detecting that. It doesn't provide distance or BTN_TOOL_PEN
either, so our heuristics can't hook onto anything. BTN_TOUCH is set by this
tablet but not at consistent pressure thresholds.

Work around this by shipping a quirk that ups it to 70. Aiptek
re-uses USB IDs because of course they do, so this applies to more than one
device. Let's see what breaks.

Fixes #462

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
(cherry picked from commit 72af32c89e1dd03301c1b28d35afb4c513b4ed82)

2 files changed, 51 insertions, 19 deletions

diff --git a/quirks/30-vendor-aiptek.quirks b/quirks/30-vendor-aiptek.quirks
index 23194e0f..3efddb63 100644
--- a/quirks/30-vendor-aiptek.quirks
+++ b/quirks/30-vendor-aiptek.quirks
@@ -5,3 +5,10 @@ MatchUdevType=tablet
 MatchBus=usb
 MatchVendor=0x08CA
 AttrEventCodeDisable=ABS_TILT_X;ABS_TILT_Y;
+
+[Aiptek 8000U pressure threshold]
+MatchUdevType=tablet
+MatchBus=usb
+MatchVendor=0x08CA
+MatchProduct=0x0010
+AttrPressureRange=70:50
diff --git a/src/evdev-tablet.c b/src/evdev-tablet.c
index cd07ae0a..dc7eebfb 100644
--- a/src/evdev-tablet.c
+++ b/src/evdev-tablet.c
@@ -1066,6 +1066,49 @@ axis_range_percentage(const struct input_absinfo *a, double percent)
 	return (a->maximum - a->minimum) * percent/100.0 + a->minimum;
 }
 
+static inline void
+tool_set_pressure_thresholds(struct tablet_dispatch *tablet,
+			     struct libinput_tablet_tool *tool)
+{
+	struct evdev_device *device = tablet->device;
+	const struct input_absinfo *pressure;
+	struct quirks_context *quirks = NULL;
+	struct quirks *q = NULL;
+	struct quirk_range r;
+	int lo = 0, hi = 1;
+
+	tool->pressure_offset = 0;
+	tool->has_pressure_offset = false;
+
+	pressure = libevdev_get_abs_info(device->evdev, ABS_PRESSURE);
+	if (!pressure)
+		goto out;
+
+	quirks = evdev_libinput_context(device)->quirks;
+	q = quirks_fetch_for_device(quirks, device->udev_device);
+
+	tool->pressure_offset = pressure->minimum;
+
+	/* 5 and 1% of the pressure range */
+	hi = axis_range_percentage(pressure, 5);
+	lo = axis_range_percentage(pressure, 1);
+
+	if (q && quirks_get_range(q, QUIRK_ATTR_PRESSURE_RANGE, &r)) {
+		if (r.lower >= r.upper) {
+			evdev_log_info(device,
+				       "Invalid pressure range, using defaults\n");
+		} else {
+			hi = r.upper;
+			lo = r.lower;
+		}
+	}
+out:
+	tool->pressure_threshold.upper = hi;
+	tool->pressure_threshold.lower = lo;
+
+	quirks_unref(q);
+}
+
 static struct libinput_tablet_tool *
 tablet_get_tool(struct tablet_dispatch *tablet,
 		enum libinput_tablet_tool_type type,
@@ -1116,8 +1159,6 @@ tablet_get_tool(struct tablet_dispatch *tablet,
 	/* If we didn't already have the new_tool in our list of tools,
 	 * add it */
 	if (!tool) {
-		const struct input_absinfo *pressure;
-
 		tool = zalloc(sizeof *tool);
 
 		*tool = (struct libinput_tablet_tool) {
@@ -1127,23 +1168,7 @@ tablet_get_tool(struct tablet_dispatch *tablet,
 			.refcount = 1,
 		};
 
-		tool->pressure_offset = 0;
-		tool->has_pressure_offset = false;
-		tool->pressure_threshold.lower = 0;
-		tool->pressure_threshold.upper = 1;
-
-		pressure = libevdev_get_abs_info(tablet->device->evdev,
-						 ABS_PRESSURE);
-		if (pressure) {
-			tool->pressure_offset = pressure->minimum;
-
-			/* 5 and 1% of the pressure range */
-			tool->pressure_threshold.upper =
-				axis_range_percentage(pressure, 5);
-			tool->pressure_threshold.lower =
-				axis_range_percentage(pressure, 1);
-		}
-
+		tool_set_pressure_thresholds(tablet, tool);
 		tool_set_bits(tablet, tool);
 
 		list_insert(tool_list, &tool->link);