[linux-2.6-block.git] / drivers / input / touchscreen / of_touchscreen.c

/*
 *  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/of.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>

static bool touchscreen_get_prop_u32(struct device_node *np,
				     const char *property,
				     unsigned int default_value,
				     unsigned int *value)
{
	u32 val;
	int error;

	error = of_property_read_u32(np, 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_of_params - parse common touchscreen DT properties
 * @dev: device that should be parsed
 *
 * This function parses common DT properties for touchscreens and setups the
 * input device accordingly. The function keeps previously setuped default
 * values if no value is specified via DT.
 */
void touchscreen_parse_of_params(struct input_dev *dev, bool multitouch)
{
	struct device_node *np = dev->dev.parent->of_node;
	unsigned int axis;
	unsigned int maximum, fuzz;
	bool data_present;

	input_alloc_absinfo(dev);
	if (!dev->absinfo)
		return;

	axis = multitouch ? ABS_MT_POSITION_X : ABS_X;
	data_present = touchscreen_get_prop_u32(np, "touchscreen-size-x",
						input_abs_get_max(dev, axis),
						&maximum) |
		       touchscreen_get_prop_u32(np, "touchscreen-fuzz-x",
						input_abs_get_fuzz(dev, axis),
						&fuzz);
	if (data_present)
		touchscreen_set_params(dev, axis, maximum, fuzz);

	axis = multitouch ? ABS_MT_POSITION_Y : ABS_Y;
	data_present = touchscreen_get_prop_u32(np, "touchscreen-size-y",
						input_abs_get_max(dev, axis),
						&maximum) |
		       touchscreen_get_prop_u32(np, "touchscreen-fuzz-y",
						input_abs_get_fuzz(dev, axis),
						&fuzz);
	if (data_present)
		touchscreen_set_params(dev, axis, maximum, fuzz);

	axis = multitouch ? ABS_MT_PRESSURE : ABS_PRESSURE;
	data_present = touchscreen_get_prop_u32(np, "touchscreen-max-pressure",
						input_abs_get_max(dev, axis),
						&maximum) |
		       touchscreen_get_prop_u32(np, "touchscreen-fuzz-pressure",
						input_abs_get_fuzz(dev, axis),
						&fuzz);
	if (data_present)
		touchscreen_set_params(dev, axis, maximum, fuzz);
}
EXPORT_SYMBOL(touchscreen_parse_of_params);
Commit	Line	Data
b98abe52 SR	1	/*
	2	* Generic DT helper functions for touchscreen devices
	3	*
	4	* Copyright (c) 2014 Sebastian Reichel <sre@kernel.org>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*
	10	*/
	11
	12	#include <linux/of.h>
	13	#include <linux/input.h>
0a363a38	14	#include <linux/input/mt.h>
b98abe52 SR	15	#include <linux/input/touchscreen.h>
b98abe52 SR	16
7c494375 DT	17	static bool touchscreen_get_prop_u32(struct device_node *np,
	18	const char *property,
	19	unsigned int default_value,
	20	unsigned int *value)
3eea8b5d	21	{
7c494375 DT	22	u32 val;
7c494375 DT	23	int error;
3eea8b5d	24
7c494375 DT	25	error = of_property_read_u32(np, property, &val);
	26	if (error) {
	27	*value = default_value;
	28	return false;
	29	}
3eea8b5d	30
7c494375 DT	31	*value = val;
7c494375 DT	32	return true;
3eea8b5d MR	33	}
	34
	35	static void touchscreen_set_params(struct input_dev *dev,
	36	unsigned long axis,
	37	int max, int fuzz)
	38	{
	39	struct input_absinfo *absinfo;
	40
	41	if (!test_bit(axis, dev->absbit)) {
f61fd21d DT	42	dev_warn(&dev->dev,
	43	"DT specifies parameters but the axis %lu is not set up\n",
	44	axis);
3eea8b5d MR	45	return;
	46	}
	47
	48	absinfo = &dev->absinfo[axis];
	49	absinfo->maximum = max;
	50	absinfo->fuzz = fuzz;
	51	}
	52
b98abe52 SR	53	/**
	54	* touchscreen_parse_of_params - parse common touchscreen DT properties
	55	* @dev: device that should be parsed
	56	*
	57	* This function parses common DT properties for touchscreens and setups the
	58	* input device accordingly. The function keeps previously setuped default
	59	* values if no value is specified via DT.
	60	*/
7c494375	61	void touchscreen_parse_of_params(struct input_dev *dev, bool multitouch)
b98abe52 SR	62	{
b98abe52 SR	63	struct device_node *np = dev->dev.parent->of_node;
7c494375 DT	64	unsigned int axis;
	65	unsigned int maximum, fuzz;
	66	bool data_present;
b98abe52 SR	67
	68	input_alloc_absinfo(dev);
	69	if (!dev->absinfo)
	70	return;
	71
7c494375 DT	72	axis = multitouch ? ABS_MT_POSITION_X : ABS_X;
	73	data_present = touchscreen_get_prop_u32(np, "touchscreen-size-x",
	74	input_abs_get_max(dev, axis),
	75	&maximum) \|
	76	touchscreen_get_prop_u32(np, "touchscreen-fuzz-x",
	77	input_abs_get_fuzz(dev, axis),
	78	&fuzz);
	79	if (data_present)
	80	touchscreen_set_params(dev, axis, maximum, fuzz);
b98abe52	81
7c494375 DT	82	axis = multitouch ? ABS_MT_POSITION_Y : ABS_Y;
	83	data_present = touchscreen_get_prop_u32(np, "touchscreen-size-y",
	84	input_abs_get_max(dev, axis),
	85	&maximum) \|
	86	touchscreen_get_prop_u32(np, "touchscreen-fuzz-y",
	87	input_abs_get_fuzz(dev, axis),
	88	&fuzz);
	89	if (data_present)
	90	touchscreen_set_params(dev, axis, maximum, fuzz);
b98abe52	91
7c494375 DT	92	axis = multitouch ? ABS_MT_PRESSURE : ABS_PRESSURE;
	93	data_present = touchscreen_get_prop_u32(np, "touchscreen-max-pressure",
	94	input_abs_get_max(dev, axis),
	95	&maximum) \|
	96	touchscreen_get_prop_u32(np, "touchscreen-fuzz-pressure",
	97	input_abs_get_fuzz(dev, axis),
	98	&fuzz);
	99	if (data_present)
	100	touchscreen_set_params(dev, axis, maximum, fuzz);
b98abe52 SR	101	}
b98abe52 SR	102	EXPORT_SYMBOL(touchscreen_parse_of_params);