v4.19.13 snapshot.
diff --git a/drivers/input/touchscreen/of_touchscreen.c b/drivers/input/touchscreen/of_touchscreen.c
new file mode 100644
index 0000000..9642f10
--- /dev/null
+++ b/drivers/input/touchscreen/of_touchscreen.c
@@ -0,0 +1,191 @@
+/*
+ * Generic DT helper functions for touchscreen devices
+ *
+ * Copyright (c) 2014 Sebastian Reichel <sre@kernel.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/property.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <linux/module.h>
+
+static bool touchscreen_get_prop_u32(struct device *dev,
+ const char *property,
+ unsigned int default_value,
+ unsigned int *value)
+{
+ u32 val;
+ int error;
+
+ error = device_property_read_u32(dev, property, &val);
+ if (error) {
+ *value = default_value;
+ return false;
+ }
+
+ *value = val;
+ return true;
+}
+
+static void touchscreen_set_params(struct input_dev *dev,
+ unsigned long axis,
+ int max, int fuzz)
+{
+ struct input_absinfo *absinfo;
+
+ if (!test_bit(axis, dev->absbit)) {
+ dev_warn(&dev->dev,
+ "DT specifies parameters but the axis %lu is not set up\n",
+ axis);
+ return;
+ }
+
+ absinfo = &dev->absinfo[axis];
+ absinfo->maximum = max;
+ absinfo->fuzz = fuzz;
+}
+
+/**
+ * touchscreen_parse_properties - parse common touchscreen DT properties
+ * @input: input device that should be parsed
+ * @multitouch: specifies whether parsed properties should be applied to
+ * single-touch or multi-touch axes
+ * @prop: pointer to a struct touchscreen_properties into which to store
+ * axis swap and invert info for use with touchscreen_report_x_y();
+ * or %NULL
+ *
+ * This function parses common DT properties for touchscreens and setups the
+ * input device accordingly. The function keeps previously set up default
+ * values if no value is specified via DT.
+ */
+void touchscreen_parse_properties(struct input_dev *input, bool multitouch,
+ struct touchscreen_properties *prop)
+{
+ struct device *dev = input->dev.parent;
+ unsigned int axis;
+ unsigned int maximum, fuzz;
+ bool data_present;
+
+ input_alloc_absinfo(input);
+ if (!input->absinfo)
+ return;
+
+ axis = multitouch ? ABS_MT_POSITION_X : ABS_X;
+ data_present = touchscreen_get_prop_u32(dev, "touchscreen-size-x",
+ input_abs_get_max(input,
+ axis) + 1,
+ &maximum) |
+ touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x",
+ input_abs_get_fuzz(input, axis),
+ &fuzz);
+ if (data_present)
+ touchscreen_set_params(input, axis, maximum - 1, fuzz);
+
+ axis = multitouch ? ABS_MT_POSITION_Y : ABS_Y;
+ data_present = touchscreen_get_prop_u32(dev, "touchscreen-size-y",
+ input_abs_get_max(input,
+ axis) + 1,
+ &maximum) |
+ touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y",
+ input_abs_get_fuzz(input, axis),
+ &fuzz);
+ if (data_present)
+ touchscreen_set_params(input, axis, maximum - 1, fuzz);
+
+ axis = multitouch ? ABS_MT_PRESSURE : ABS_PRESSURE;
+ data_present = touchscreen_get_prop_u32(dev,
+ "touchscreen-max-pressure",
+ input_abs_get_max(input, axis),
+ &maximum) |
+ touchscreen_get_prop_u32(dev,
+ "touchscreen-fuzz-pressure",
+ input_abs_get_fuzz(input, axis),
+ &fuzz);
+ if (data_present)
+ touchscreen_set_params(input, axis, maximum, fuzz);
+
+ if (!prop)
+ return;
+
+ axis = multitouch ? ABS_MT_POSITION_X : ABS_X;
+
+ prop->max_x = input_abs_get_max(input, axis);
+ prop->max_y = input_abs_get_max(input, axis + 1);
+ prop->invert_x =
+ device_property_read_bool(dev, "touchscreen-inverted-x");
+ prop->invert_y =
+ device_property_read_bool(dev, "touchscreen-inverted-y");
+ prop->swap_x_y =
+ device_property_read_bool(dev, "touchscreen-swapped-x-y");
+
+ if (prop->swap_x_y)
+ swap(input->absinfo[axis], input->absinfo[axis + 1]);
+}
+EXPORT_SYMBOL(touchscreen_parse_properties);
+
+static void
+touchscreen_apply_prop_to_x_y(const struct touchscreen_properties *prop,
+ unsigned int *x, unsigned int *y)
+{
+ if (prop->invert_x)
+ *x = prop->max_x - *x;
+
+ if (prop->invert_y)
+ *y = prop->max_y - *y;
+
+ if (prop->swap_x_y)
+ swap(*x, *y);
+}
+
+/**
+ * touchscreen_set_mt_pos - Set input_mt_pos coordinates
+ * @pos: input_mt_pos to set coordinates of
+ * @prop: pointer to a struct touchscreen_properties
+ * @x: X coordinate to store in pos
+ * @y: Y coordinate to store in pos
+ *
+ * Adjust the passed in x and y values applying any axis inversion and
+ * swapping requested in the passed in touchscreen_properties and store
+ * the result in a struct input_mt_pos.
+ */
+void touchscreen_set_mt_pos(struct input_mt_pos *pos,
+ const struct touchscreen_properties *prop,
+ unsigned int x, unsigned int y)
+{
+ touchscreen_apply_prop_to_x_y(prop, &x, &y);
+ pos->x = x;
+ pos->y = y;
+}
+EXPORT_SYMBOL(touchscreen_set_mt_pos);
+
+/**
+ * touchscreen_report_pos - Report touchscreen coordinates
+ * @input: input_device to report coordinates for
+ * @prop: pointer to a struct touchscreen_properties
+ * @x: X coordinate to report
+ * @y: Y coordinate to report
+ * @multitouch: Report coordinates on single-touch or multi-touch axes
+ *
+ * Adjust the passed in x and y values applying any axis inversion and
+ * swapping requested in the passed in touchscreen_properties and then
+ * report the resulting coordinates on the input_dev's x and y axis.
+ */
+void touchscreen_report_pos(struct input_dev *input,
+ const struct touchscreen_properties *prop,
+ unsigned int x, unsigned int y,
+ bool multitouch)
+{
+ touchscreen_apply_prop_to_x_y(prop, &x, &y);
+ input_report_abs(input, multitouch ? ABS_MT_POSITION_X : ABS_X, x);
+ input_report_abs(input, multitouch ? ABS_MT_POSITION_Y : ABS_Y, y);
+}
+EXPORT_SYMBOL(touchscreen_report_pos);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Device-tree helpers functions for touchscreen devices");