// SPDX-License-Identifier: GPL-2.0-only/* *  Generic helper functions for touchscreens and other two-dimensional *  pointing devices * *  Copyright (c) 2014 Sebastian Reichel <sre@kernel.org> */ #include <linux/export.h>#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 min, int max, int fuzz){	struct input_absinfo *absinfo; 	if (!test_bit(axis, dev->absbit)) {		dev_warn(&dev->dev,			 "Parameters are specified but the axis %lu is not set up\n",			 axis);		return;	} 	absinfo = &dev->absinfo[axis];	absinfo->minimum = min;	absinfo->maximum = max;	absinfo->fuzz = fuzz;} /** * touchscreen_parse_properties - parse common touchscreen 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 properties for touchscreens and sets up the * input device accordingly. The function keeps previously set up default * values if no value is specified. */void touchscreen_parse_properties(struct input_dev *input, bool multitouch,				  struct touchscreen_properties *prop){	struct device *dev = input->dev.parent;	struct input_absinfo *absinfo;	unsigned int axis, axis_x, axis_y;	unsigned int minimum, maximum, fuzz;	bool data_present; 	input_alloc_absinfo(input);	if (!input->absinfo)		return; 	axis_x = multitouch ? ABS_MT_POSITION_X : ABS_X;	axis_y = multitouch ? ABS_MT_POSITION_Y : ABS_Y; 	data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-x",						input_abs_get_min(input, axis_x),						&minimum);	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-x",						 input_abs_get_max(input,								   axis_x) + 1,						 &maximum);	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x",						 input_abs_get_fuzz(input, axis_x),						 &fuzz);	if (data_present)		touchscreen_set_params(input, axis_x, minimum, maximum - 1, fuzz); 	data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-y",						input_abs_get_min(input, axis_y),						&minimum);	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-y",						 input_abs_get_max(input,								   axis_y) + 1,						 &maximum);	data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y",						 input_abs_get_fuzz(input, axis_y),						 &fuzz);	if (data_present)		touchscreen_set_params(input, axis_y, minimum, 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);	data_present |= touchscreen_get_prop_u32(dev,						 "touchscreen-fuzz-pressure",						 input_abs_get_fuzz(input, axis),						 &fuzz);	if (data_present)		touchscreen_set_params(input, axis, 0, maximum, fuzz); 	if (!prop)		return; 	prop->max_x = input_abs_get_max(input, axis_x);	prop->max_y = input_abs_get_max(input, axis_y); 	prop->invert_x =		device_property_read_bool(dev, "touchscreen-inverted-x");	if (prop->invert_x) {		absinfo = &input->absinfo[axis_x];		absinfo->maximum -= absinfo->minimum;		absinfo->minimum = 0;	} 	prop->invert_y =		device_property_read_bool(dev, "touchscreen-inverted-y");	if (prop->invert_y) {		absinfo = &input->absinfo[axis_y];		absinfo->maximum -= absinfo->minimum;		absinfo->minimum = 0;	} 	prop->swap_x_y =		device_property_read_bool(dev, "touchscreen-swapped-x-y");	if (prop->swap_x_y)		swap(input->absinfo[axis_x], input->absinfo[axis_y]);}EXPORT_SYMBOL(touchscreen_parse_properties); static voidtouchscreen_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("Helper functions for touchscreens and other devices");