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1// SPDX-License-Identifier: GPL-2.0-or-later2/*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_dev *idev)29{30 s8 x, y, z;31 32 mutex_lock(&ams_info.lock);33 34 ams_sensors(&x, &y, &z);35 36 x -= ams_info.xcalib;37 y -= ams_info.ycalib;38 z -= ams_info.zcalib;39 40 input_report_abs(idev, ABS_X, invert ? -x : x);41 input_report_abs(idev, ABS_Y, invert ? -y : y);42 input_report_abs(idev, ABS_Z, z);43 44 input_sync(idev);45 46 mutex_unlock(&ams_info.lock);47}48 49/* Call with ams_info.lock held! */50static int ams_input_enable(void)51{52 struct input_dev *input;53 s8 x, y, z;54 int error;55 56 ams_sensors(&x, &y, &z);57 ams_info.xcalib = x;58 ams_info.ycalib = y;59 ams_info.zcalib = z;60 61 input = input_allocate_device();62 if (!input)63 return -ENOMEM;64 65 input->name = "Apple Motion Sensor";66 input->id.bustype = ams_info.bustype;67 input->id.vendor = 0;68 input->dev.parent = &ams_info.of_dev->dev;69 70 input_set_abs_params(input, ABS_X, -50, 50, 3, 0);71 input_set_abs_params(input, ABS_Y, -50, 50, 3, 0);72 input_set_abs_params(input, ABS_Z, -50, 50, 3, 0);73 input_set_capability(input, EV_KEY, BTN_TOUCH);74 75 error = input_setup_polling(input, ams_idev_poll);76 if (error)77 goto err_free_input;78 79 input_set_poll_interval(input, 25);80 81 error = input_register_device(input);82 if (error)83 goto err_free_input;84 85 ams_info.idev = input;86 joystick = true;87 88 return 0;89 90err_free_input:91 input_free_device(input);92 return error;93}94 95static void ams_input_disable(void)96{97 if (ams_info.idev) {98 input_unregister_device(ams_info.idev);99 ams_info.idev = NULL;100 }101 102 joystick = false;103}104 105static ssize_t ams_input_show_joystick(struct device *dev,106 struct device_attribute *attr, char *buf)107{108 return sprintf(buf, "%d\n", joystick);109}110 111static ssize_t ams_input_store_joystick(struct device *dev,112 struct device_attribute *attr, const char *buf, size_t count)113{114 unsigned long enable;115 int error = 0;116 int ret;117 118 ret = kstrtoul(buf, 0, &enable);119 if (ret)120 return ret;121 if (enable > 1)122 return -EINVAL;123 124 mutex_lock(&ams_input_mutex);125 126 if (enable != joystick) {127 if (enable)128 error = ams_input_enable();129 else130 ams_input_disable();131 }132 133 mutex_unlock(&ams_input_mutex);134 135 return error ? error : count;136}137 138static DEVICE_ATTR(joystick, S_IRUGO | S_IWUSR,139 ams_input_show_joystick, ams_input_store_joystick);140 141int ams_input_init(void)142{143 if (joystick)144 ams_input_enable();145 146 return device_create_file(&ams_info.of_dev->dev, &dev_attr_joystick);147}148 149void ams_input_exit(void)150{151 device_remove_file(&ams_info.of_dev->dev, &dev_attr_joystick);152 153 mutex_lock(&ams_input_mutex);154 ams_input_disable();155 mutex_unlock(&ams_input_mutex);156}157