1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (c) 1999-2001 Vojtech Pavlik
4 */
5
6/*
7 * Magellan and Space Mouse 6dof controller driver for Linux
8 */
9
10/*
11 */
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/input.h>
17#include <linux/serio.h>
18
19#define DRIVER_DESC	"Magellan and SpaceMouse 6dof controller driver"
20
21MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
22MODULE_DESCRIPTION(DRIVER_DESC);
23MODULE_LICENSE("GPL");
24
25/*
26 * Definitions & global arrays.
27 */
28
29#define	MAGELLAN_MAX_LENGTH	32
30
31static int magellan_buttons[] = { BTN_0, BTN_1, BTN_2, BTN_3, BTN_4, BTN_5, BTN_6, BTN_7, BTN_8 };
32static int magellan_axes[] = { ABS_X, ABS_Y, ABS_Z, ABS_RX, ABS_RY, ABS_RZ };
33
34/*
35 * Per-Magellan data.
36 */
37
38struct magellan {
39	struct input_dev *dev;
40	int idx;
41	unsigned char data[MAGELLAN_MAX_LENGTH];
42	char phys[32];
43};
44
45/*
46 * magellan_crunch_nibbles() verifies that the bytes sent from the Magellan
47 * have correct upper nibbles for the lower ones, if not, the packet will
48 * be thrown away. It also strips these upper halves to simplify further
49 * processing.
50 */
51
52static int magellan_crunch_nibbles(unsigned char *data, int count)
53{
54	static unsigned char nibbles[16] = "0AB3D56GH9:K<MN?";
55
56	do {
57		if (data[count] == nibbles[data[count] & 0xf])
58			data[count] = data[count] & 0xf;
59		else
60			return -1;
61	} while (--count);
62
63	return 0;
64}
65
66static void magellan_process_packet(struct magellan* magellan)
67{
68	struct input_dev *dev = magellan->dev;
69	unsigned char *data = magellan->data;
70	int i, t;
71
72	if (!magellan->idx) return;
73
74	switch (magellan->data[0]) {
75
76		case 'd':				/* Axis data */
77			if (magellan->idx != 25) return;
78			if (magellan_crunch_nibbles(data, 24)) return;
79			for (i = 0; i < 6; i++)
80				input_report_abs(dev, magellan_axes[i],
81					(data[(i << 2) + 1] << 12 | data[(i << 2) + 2] << 8 |
82					 data[(i << 2) + 3] <<  4 | data[(i << 2) + 4]) - 32768);
83			break;
84
85		case 'k':				/* Button data */
86			if (magellan->idx != 4) return;
87			if (magellan_crunch_nibbles(data, 3)) return;
88			t = (data[1] << 1) | (data[2] << 5) | data[3];
89			for (i = 0; i < 9; i++) input_report_key(dev, magellan_buttons[i], (t >> i) & 1);
90			break;
91	}
92
93	input_sync(dev);
94}
95
96static irqreturn_t magellan_interrupt(struct serio *serio,
97		unsigned char data, unsigned int flags)
98{
99	struct magellan* magellan = serio_get_drvdata(serio);
100
101	if (data == '\r') {
102		magellan_process_packet(magellan);
103		magellan->idx = 0;
104	} else {
105		if (magellan->idx < MAGELLAN_MAX_LENGTH)
106			magellan->data[magellan->idx++] = data;
107	}
108	return IRQ_HANDLED;
109}
110
111/*
112 * magellan_disconnect() is the opposite of magellan_connect()
113 */
114
115static void magellan_disconnect(struct serio *serio)
116{
117	struct magellan* magellan = serio_get_drvdata(serio);
118
119	serio_close(serio);
120	serio_set_drvdata(serio, NULL);
121	input_unregister_device(magellan->dev);
122	kfree(magellan);
123}
124
125/*
126 * magellan_connect() is the routine that is called when someone adds a
127 * new serio device that supports Magellan protocol and registers it as
128 * an input device.
129 */
130
131static int magellan_connect(struct serio *serio, struct serio_driver *drv)
132{
133	struct magellan *magellan;
134	struct input_dev *input_dev;
135	int err = -ENOMEM;
136	int i;
137
138	magellan = kzalloc(sizeof(struct magellan), GFP_KERNEL);
139	input_dev = input_allocate_device();
140	if (!magellan || !input_dev)
141		goto fail1;
142
143	magellan->dev = input_dev;
144	snprintf(magellan->phys, sizeof(magellan->phys), "%s/input0", serio->phys);
145
146	input_dev->name = "LogiCad3D Magellan / SpaceMouse";
147	input_dev->phys = magellan->phys;
148	input_dev->id.bustype = BUS_RS232;
149	input_dev->id.vendor = SERIO_MAGELLAN;
150	input_dev->id.product = 0x0001;
151	input_dev->id.version = 0x0100;
152	input_dev->dev.parent = &serio->dev;
153
154	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
155
156	for (i = 0; i < 9; i++)
157		set_bit(magellan_buttons[i], input_dev->keybit);
158
159	for (i = 0; i < 6; i++)
160		input_set_abs_params(input_dev, magellan_axes[i], -360, 360, 0, 0);
161
162	serio_set_drvdata(serio, magellan);
163
164	err = serio_open(serio, drv);
165	if (err)
166		goto fail2;
167
168	err = input_register_device(magellan->dev);
169	if (err)
170		goto fail3;
171
172	return 0;
173
174 fail3:	serio_close(serio);
175 fail2:	serio_set_drvdata(serio, NULL);
176 fail1:	input_free_device(input_dev);
177	kfree(magellan);
178	return err;
179}
180
181/*
182 * The serio driver structure.
183 */
184
185static const struct serio_device_id magellan_serio_ids[] = {
186	{
187		.type	= SERIO_RS232,
188		.proto	= SERIO_MAGELLAN,
189		.id	= SERIO_ANY,
190		.extra	= SERIO_ANY,
191	},
192	{ 0 }
193};
194
195MODULE_DEVICE_TABLE(serio, magellan_serio_ids);
196
197static struct serio_driver magellan_drv = {
198	.driver		= {
199		.name	= "magellan",
200	},
201	.description	= DRIVER_DESC,
202	.id_table	= magellan_serio_ids,
203	.interrupt	= magellan_interrupt,
204	.connect	= magellan_connect,
205	.disconnect	= magellan_disconnect,
206};
207
208module_serio_driver(magellan_drv);
209