LXR linux/drivers/macintosh/ams/ams-input.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Apple Motion Sensor driver (joystick emulation)
   4 *
   5 * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
   6 * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
   7 */
   8
   9#include <linux/module.h>
  10
  11#include <linux/types.h>
  12#include <linux/errno.h>
  13#include <linux/init.h>
  14#include <linux/delay.h>
  15
  16#include "ams.h"
  17
  18static bool joystick;
  19module_param(joystick, bool, S_IRUGO);
  20MODULE_PARM_DESC(joystick, "Enable the input class device on module load");
  21
  22static bool invert;
  23module_param(invert, bool, S_IWUSR | S_IRUGO);
  24MODULE_PARM_DESC(invert, "Invert input data on X and Y axis");
  25
  26static DEFINE_MUTEX(ams_input_mutex);
  27
  28static void ams_idev_poll(struct input_polled_dev *dev)
  29{
  30        struct input_dev *idev = dev->input;
  31        s8 x, y, z;
  32
  33        mutex_lock(&ams_info.lock);
  34
  35        ams_sensors(&x, &y, &z);
  36
  37        x -= ams_info.xcalib;
  38        y -= ams_info.ycalib;
  39        z -= ams_info.zcalib;
  40
  41        input_report_abs(idev, ABS_X, invert ? -x : x);
  42        input_report_abs(idev, ABS_Y, invert ? -y : y);
  43        input_report_abs(idev, ABS_Z, z);
  44
  45        input_sync(idev);
  46
  47        mutex_unlock(&ams_info.lock);
  48}
  49
  50/* Call with ams_info.lock held! */
  51static int ams_input_enable(void)
  52{
  53        struct input_dev *input;
  54        s8 x, y, z;
  55        int error;
  56
  57        ams_sensors(&x, &y, &z);
  58        ams_info.xcalib = x;
  59        ams_info.ycalib = y;
  60        ams_info.zcalib = z;
  61
  62        ams_info.idev = input_allocate_polled_device();
  63        if (!ams_info.idev)
  64                return -ENOMEM;
  65
  66        ams_info.idev->poll = ams_idev_poll;
  67        ams_info.idev->poll_interval = 25;
  68
  69        input = ams_info.idev->input;
  70        input->name = "Apple Motion Sensor";
  71        input->id.bustype = ams_info.bustype;
  72        input->id.vendor = 0;
  73        input->dev.parent = &ams_info.of_dev->dev;
  74
  75        input_set_abs_params(input, ABS_X, -50, 50, 3, 0);
  76        input_set_abs_params(input, ABS_Y, -50, 50, 3, 0);
  77        input_set_abs_params(input, ABS_Z, -50, 50, 3, 0);
  78
  79        set_bit(EV_ABS, input->evbit);
  80        set_bit(EV_KEY, input->evbit);
  81        set_bit(BTN_TOUCH, input->keybit);
  82
  83        error = input_register_polled_device(ams_info.idev);
  84        if (error) {
  85                input_free_polled_device(ams_info.idev);
  86                ams_info.idev = NULL;
  87                return error;
  88        }
  89
  90        joystick = true;
  91
  92        return 0;
  93}
  94
  95static void ams_input_disable(void)
  96{
  97        if (ams_info.idev) {
  98                input_unregister_polled_device(ams_info.idev);
  99                input_free_polled_device(ams_info.idev);
 100                ams_info.idev = NULL;
 101        }
 102
 103        joystick = false;
 104}
 105
 106static ssize_t ams_input_show_joystick(struct device *dev,
 107        struct device_attribute *attr, char *buf)
 108{
 109        return sprintf(buf, "%d\n", joystick);
 110}
 111
 112static ssize_t ams_input_store_joystick(struct device *dev,
 113        struct device_attribute *attr, const char *buf, size_t count)
 114{
 115        unsigned long enable;
 116        int error = 0;
 117        int ret;
 118
 119        ret = kstrtoul(buf, 0, &enable);
 120        if (ret)
 121                return ret;
 122        if (enable > 1)
 123                return -EINVAL;
 124
 125        mutex_lock(&ams_input_mutex);
 126
 127        if (enable != joystick) {
 128                if (enable)
 129                        error = ams_input_enable();
 130                else
 131                        ams_input_disable();
 132        }
 133
 134        mutex_unlock(&ams_input_mutex);
 135
 136        return error ? error : count;
 137}
 138
 139static DEVICE_ATTR(joystick, S_IRUGO | S_IWUSR,
 140        ams_input_show_joystick, ams_input_store_joystick);
 141
 142int ams_input_init(void)
 143{
 144        if (joystick)
 145                ams_input_enable();
 146
 147        return device_create_file(&ams_info.of_dev->dev, &dev_attr_joystick);
 148}
 149
 150void ams_input_exit(void)
 151{
 152        device_remove_file(&ams_info.of_dev->dev, &dev_attr_joystick);
 153
 154        mutex_lock(&ams_input_mutex);
 155        ams_input_disable();
 156        mutex_unlock(&ams_input_mutex);
 157}
 158