drivers/hid/hid-magicmouse.c


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./packaging/docker/Dockerfile
/*
 *   Apple "Magic" Wireless Mouse driver
 *
 *   Copyright (c) 2010 Michael Poole <mdpoole@troilus.org>
 *   Copyright (c) 2010 Chase Douglas <chase.douglas@canonical.com>
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 */

#include <linux/device.h>
#include <linux/hid.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb.h>

#include "hid-ids.h"

static bool emulate_3button = true;
module_param(emulate_3button, bool, 0644);
MODULE_PARM_DESC(emulate_3button, "Emulate a middle button");

static int middle_button_start = -350;
static int middle_button_stop = +350;

static bool emulate_scroll_wheel = true;
module_param(emulate_scroll_wheel, bool, 0644);
MODULE_PARM_DESC(emulate_scroll_wheel, "Emulate a scroll wheel");

static unsigned int scroll_speed = 32;
static int param_set_scroll_speed(const char *val, struct kernel_param *kp) {
	unsigned long speed;
	if (!val || strict_strtoul(val, 0, &speed) || speed > 63)
		return -EINVAL;
	scroll_speed = speed;
	return 0;
}
module_param_call(scroll_speed, param_set_scroll_speed, param_get_uint, &scroll_speed, 0644);
MODULE_PARM_DESC(scroll_speed, "Scroll speed, value from 0 (slow) to 63 (fast)");

static bool scroll_acceleration = false;
module_param(scroll_acceleration, bool, 0644);
MODULE_PARM_DESC(scroll_acceleration, "Accelerate sequential scroll events");

static bool report_touches = true;
module_param(report_touches, bool, 0644);
MODULE_PARM_DESC(report_touches, "Emit touch records (otherwise, only use them for emulation)");

static bool report_undeciphered;
module_param(report_undeciphered, bool, 0644);
MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state field using a MSC_RAW event");

#define TRACKPAD_REPORT_ID 0x28
#define MOUSE_REPORT_ID    0x29
#define DOUBLE_REPORT_ID   0xf7
/* These definitions are not precise, but they're close enough.  (Bits
 * 0x03 seem to indicate the aspect ratio of the touch, bits 0x70 seem
 * to be some kind of bit mask -- 0x20 may be a near-field reading,
 * and 0x40 is actual contact, and 0x10 may be a start/stop or change
 * indication.)
 */
#define TOUCH_STATE_MASK  0xf0
#define TOUCH_STATE_NONE  0x00
#define TOUCH_STATE_START 0x30
#define TOUCH_STATE_DRAG  0x40

#define SCROLL_ACCEL_DEFAULT 7

/* Single touch emulation should only begin when no touches are currently down.
 * This is true when single_touch_id is equal to NO_TOUCHES. If multiple touches
 * are down and the touch providing for single touch emulation is lifted,
 * single_touch_id is equal to SINGLE_TOUCH_UP. While single touch emulation is
 * occuring, single_touch_id corresponds with the tracking id of the touch used.
 */
#define NO_TOUCHES -1
#define SINGLE_TOUCH_UP -2

/**
 * struct magicmouse_sc - Tracks Magic Mouse-specific data.
 * @input: Input device through which we report events.
 * @quirks: Currently unused.
 * @ntouches: Number of touches in most recent touch report.
 * @scroll_accel: Number of consecutive scroll motions.
 * @scroll_jiffies: Time of last scroll motion.
 * @touches: Most recent data for a touch, indexed by tracking ID.
 * @tracking_ids: Mapping of current touch input data to @touches.
 */
struct magicmouse_sc {
	struct input_dev *input;
	unsigned long quirks;

	int ntouches;
	int scroll_accel;
	unsigned long scroll_jiffies;

	struct {
		short x;
		short y;
		short scroll_x;
		short scroll_y;
		u8 size;
	} touches[16];
	int tracking_ids[16];
	int single_touch_id;
};

static int magicmouse_firm_touch(struct magicmouse_sc *msc)
{
	int touch = -1;
	int ii;

	/* If there is only one "firm" touch, set touch to its
	 * tracking ID.
	 */
	for (ii = 0; ii < msc->ntouches; ii++) {
		int idx = msc->tracking_ids[ii];
		if (msc->touches[idx].size < 8) {
			/* Ignore this touch. */
		} else if (touch >= 0) {
			touch = -1;
			break;
		} else {
			touch = idx;
		}
	}

	return touch;
}

static void magicmouse_emit_buttons(struct magicmouse_sc *msc, int state)
{
	int last_state = test_bit(BTN_LEFT, msc->input->key) << 0 |
		test_bit(BTN_RIGHT, msc->input->key) << 1 |
		test_bit(BTN_MIDDLE, msc->input->key) << 2;

	if (emulate_3button) {
		int id;

		/* If some button was pressed before, keep it held
		 * down.  Otherwise, if there's exactly one firm
		 * touch, use that to override the mouse's guess.
		 */
		if (state == 0) {
			/* The button was released. */
		} else if (last_state != 0) {
			state = last_state;
		} else if ((id = magicmouse_firm_touch(msc)) >= 0) {
			int x = msc->touches[id].x;
			if (x < middle_button_start)
				state = 1;
			else if (x > middle_button_stop)
				state = 2;
			else
				state = 4;
		} /* else: we keep the mouse's guess */

		input_report_key(msc->input, BTN_MIDDLE, state & 4);
	}

	input_report_key(msc->input, BTN_LEFT, state & 1);
	input_report_key(msc->input, BTN_RIGHT, state & 2);

	if (state != last_state)
		msc->scroll_accel = SCROLL_ACCEL_DEFAULT;
}

static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tdata)
{
	struct input_dev *input = msc->input;
	int id, x, y, size, orientation, touch_major, touch_minor, state, down;

	if (input->id.product == USB_DEVICE_ID_APPLE_MAGICMOUSE) {
		id = (tdata[6] << 2 | tdata[5] >> 6) & 0xf;
		x = (tdata[1] << 28 | tdata[0] << 20) >> 20;
		y = -((tdata[2] << 24 | tdata[1] << 16) >> 20);
		size = tdata[5] & 0x3f;
		orientation = (tdata[6] >> 2) - 32;
		touch_major = tdata[3];
		touch_minor = tdata[4];
		state = tdata[7] & TOUCH_STATE_MASK;
		down = state != TOUCH_STATE_NONE;
	} else { /* USB_DEVICE_ID_APPLE_MAGICTRACKPAD */
		id = (tdata[7] << 2 | tdata[6] >> 6) & 0xf;
		x = (tdata[1] << 27 | tdata[0] << 19) >> 19;
		y = -((tdata[3] << 30 | tdata[2] << 22 | tdata[1] << 14) >> 19);
		size = tdata[6] & 0x3f;
		orientation = (tdata[7] >> 2) - 32;
		touch_major = tdata[4];
		touch_minor = tdata[5];
		state = tdata[8] & TOUCH_STATE_MASK;
		down = state != TOUCH_STATE_NONE;
	}

	/* Store tracking ID and other fields. */
	msc->tracking_ids[raw_id] = id;
	msc->touches[id].x = x;
	msc->touches[id].y = y;
	msc->touches[id].size = size;

	/* If requested, emulate a scroll wheel by detecting small
	 * vertical touch motions.
	 */
	if (emulate_scroll_wh