/* *  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> 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 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);