LXR linux/drivers/input/touchscreen/of

   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>
  14#include <linux/input/touchscreen.h>
  15
  16/**
  17 * touchscreen_parse_of_params - parse common touchscreen DT properties
  18 * @dev: device that should be parsed
  19 *
  20 * This function parses common DT properties for touchscreens and setups the
  21 * input device accordingly. The function keeps previously setuped default
  22 * values if no value is specified via DT.
  23 */
  24void touchscreen_parse_of_params(struct input_dev *dev)
  25{
  26        struct device_node *np = dev->dev.parent->of_node;
  27        struct input_absinfo *absinfo;
  28
  29        input_alloc_absinfo(dev);
  30        if (!dev->absinfo)
  31                return;
  32
  33        absinfo = &dev->absinfo[ABS_X];
  34        of_property_read_u32(np, "touchscreen-size-x", &absinfo->maximum);
  35        of_property_read_u32(np, "touchscreen-fuzz-x", &absinfo->fuzz);
  36
  37        absinfo = &dev->absinfo[ABS_Y];
  38        of_property_read_u32(np, "touchscreen-size-y", &absinfo->maximum);
  39        of_property_read_u32(np, "touchscreen-fuzz-y", &absinfo->fuzz);
  40
  41        absinfo = &dev->absinfo[ABS_PRESSURE];
  42        of_property_read_u32(np, "touchscreen-max-pressure", &absinfo->maximum);
  43        of_property_read_u32(np, "touchscreen-fuzz-pressure", &absinfo->fuzz);
  44}
  45EXPORT_SYMBOL(touchscreen_parse_of_params);
  46