1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (c) 2000-2001 Vojtech Pavlik
4 *  Copyright (c) 2000 Mark Fletcher
5 */
6
7/*
8 * Gravis Stinger gamepad driver for Linux
9 */
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/input.h>
15#include <linux/serio.h>
16
17#define DRIVER_DESC	"Gravis Stinger gamepad driver"
18
19MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
20MODULE_DESCRIPTION(DRIVER_DESC);
21MODULE_LICENSE("GPL");
22
23/*
24 * Constants.
25 */
26
27#define STINGER_MAX_LENGTH 8
28
29/*
30 * Per-Stinger data.
31 */
32
33struct stinger {
34	struct input_dev *dev;
35	int idx;
36	unsigned char data[STINGER_MAX_LENGTH];
37	char phys[32];
38};
39
40/*
41 * stinger_process_packet() decodes packets the driver receives from the
42 * Stinger. It updates the data accordingly.
43 */
44
45static void stinger_process_packet(struct stinger *stinger)
46{
47	struct input_dev *dev = stinger->dev;
48	unsigned char *data = stinger->data;
49
50	if (!stinger->idx) return;
51
52	input_report_key(dev, BTN_A,	  ((data[0] & 0x20) >> 5));
53	input_report_key(dev, BTN_B,	  ((data[0] & 0x10) >> 4));
54	input_report_key(dev, BTN_C,	  ((data[0] & 0x08) >> 3));
55	input_report_key(dev, BTN_X,	  ((data[0] & 0x04) >> 2));
56	input_report_key(dev, BTN_Y,	  ((data[3] & 0x20) >> 5));
57	input_report_key(dev, BTN_Z,	  ((data[3] & 0x10) >> 4));
58	input_report_key(dev, BTN_TL,     ((data[3] & 0x08) >> 3));
59	input_report_key(dev, BTN_TR,     ((data[3] & 0x04) >> 2));
60	input_report_key(dev, BTN_SELECT, ((data[3] & 0x02) >> 1));
61	input_report_key(dev, BTN_START,   (data[3] & 0x01));
62
63	input_report_abs(dev, ABS_X, (data[1] & 0x3F) - ((data[0] & 0x01) << 6));
64	input_report_abs(dev, ABS_Y, ((data[0] & 0x02) << 5) - (data[2] & 0x3F));
65
66	input_sync(dev);
67
68	return;
69}
70
71/*
72 * stinger_interrupt() is called by the low level driver when characters
73 * are ready for us. We then buffer them for further processing, or call the
74 * packet processing routine.
75 */
76
77static irqreturn_t stinger_interrupt(struct serio *serio,
78	unsigned char data, unsigned int flags)
79{
80	struct stinger *stinger = serio_get_drvdata(serio);
81
82	/* All Stinger packets are 4 bytes */
83
84	if (stinger->idx < STINGER_MAX_LENGTH)
85		stinger->data[stinger->idx++] = data;
86
87	if (stinger->idx == 4) {
88		stinger_process_packet(stinger);
89		stinger->idx = 0;
90	}
91
92	return IRQ_HANDLED;
93}
94
95/*
96 * stinger_disconnect() is the opposite of stinger_connect()
97 */
98
99static void stinger_disconnect(struct serio *serio)
100{
101	struct stinger *stinger = serio_get_drvdata(serio);
102
103	serio_close(serio);
104	serio_set_drvdata(serio, NULL);
105	input_unregister_device(stinger->dev);
106	kfree(stinger);
107}
108
109/*
110 * stinger_connect() is the routine that is called when someone adds a
111 * new serio device that supports Stinger protocol and registers it as
112 * an input device.
113 */
114
115static int stinger_connect(struct serio *serio, struct serio_driver *drv)
116{
117	struct stinger *stinger;
118	struct input_dev *input_dev;
119	int err = -ENOMEM;
120
121	stinger = kmalloc(sizeof(struct stinger), GFP_KERNEL);
122	input_dev = input_allocate_device();
123	if (!stinger || !input_dev)
124		goto fail1;
125
126	stinger->dev = input_dev;
127	snprintf(stinger->phys, sizeof(stinger->phys), "%s/serio0", serio->phys);
128
129	input_dev->name = "Gravis Stinger";
130	input_dev->phys = stinger->phys;
131	input_dev->id.bustype = BUS_RS232;
132	input_dev->id.vendor = SERIO_STINGER;
133	input_dev->id.product = 0x0001;
134	input_dev->id.version = 0x0100;
135	input_dev->dev.parent = &serio->dev;
136
137	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
138	input_dev->keybit[BIT_WORD(BTN_A)] = BIT_MASK(BTN_A) | BIT_MASK(BTN_B) |
139		BIT_MASK(BTN_C) | BIT_MASK(BTN_X) | BIT_MASK(BTN_Y) |
140		BIT_MASK(BTN_Z) | BIT_MASK(BTN_TL) | BIT_MASK(BTN_TR) |
141		BIT_MASK(BTN_START) | BIT_MASK(BTN_SELECT);
142	input_set_abs_params(input_dev, ABS_X, -64, 64, 0, 4);
143	input_set_abs_params(input_dev, ABS_Y, -64, 64, 0, 4);
144
145	serio_set_drvdata(serio, stinger);
146
147	err = serio_open(serio, drv);
148	if (err)
149		goto fail2;
150
151	err = input_register_device(stinger->dev);
152	if (err)
153		goto fail3;
154
155	return 0;
156
157 fail3:	serio_close(serio);
158 fail2:	serio_set_drvdata(serio, NULL);
159 fail1:	input_free_device(input_dev);
160	kfree(stinger);
161	return err;
162}
163
164/*
165 * The serio driver structure.
166 */
167
168static const struct serio_device_id stinger_serio_ids[] = {
169	{
170		.type	= SERIO_RS232,
171		.proto	= SERIO_STINGER,
172		.id	= SERIO_ANY,
173		.extra	= SERIO_ANY,
174	},
175	{ 0 }
176};
177
178MODULE_DEVICE_TABLE(serio, stinger_serio_ids);
179
180static struct serio_driver stinger_drv = {
181	.driver		= {
182		.name	= "stinger",
183	},
184	.description	= DRIVER_DESC,
185	.id_table	= stinger_serio_ids,
186	.interrupt	= stinger_interrupt,
187	.connect	= stinger_connect,
188	.disconnect	= stinger_disconnect,
189};
190
191module_serio_driver(stinger_drv);
192