1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (c) 1999-2001 Vojtech Pavlik
4 */
5
6/*
7 * Creative Labs Blaster GamePad Cobra driver for Linux
8 */
9
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/slab.h>
13#include <linux/gameport.h>
14#include <linux/input.h>
15#include <linux/jiffies.h>
16
17#define DRIVER_DESC	"Creative Labs Blaster GamePad Cobra driver"
18
19MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
20MODULE_DESCRIPTION(DRIVER_DESC);
21MODULE_LICENSE("GPL");
22
23#define COBRA_MAX_STROBE	45	/* 45 us max wait for first strobe */
24#define COBRA_LENGTH		36
25
26static int cobra_btn[] = { BTN_START, BTN_SELECT, BTN_TL, BTN_TR, BTN_X, BTN_Y, BTN_Z, BTN_A, BTN_B, BTN_C, BTN_TL2, BTN_TR2, 0 };
27
28struct cobra {
29	struct gameport *gameport;
30	struct input_dev *dev[2];
31	int reads;
32	int bads;
33	unsigned char exists;
34	char phys[2][32];
35};
36
37static unsigned char cobra_read_packet(struct gameport *gameport, unsigned int *data)
38{
39	unsigned long flags;
40	unsigned char u, v, w;
41	__u64 buf[2];
42	int r[2], t[2];
43	int i, j, ret;
44
45	int strobe = gameport_time(gameport, COBRA_MAX_STROBE);
46
47	for (i = 0; i < 2; i++) {
48		r[i] = buf[i] = 0;
49		t[i] = COBRA_MAX_STROBE;
50	}
51
52	local_irq_save(flags);
53
54	u = gameport_read(gameport);
55
56	do {
57		t[0]--; t[1]--;
58		v = gameport_read(gameport);
59		for (i = 0, w = u ^ v; i < 2 && w; i++, w >>= 2)
60			if (w & 0x30) {
61				if ((w & 0x30) < 0x30 && r[i] < COBRA_LENGTH && t[i] > 0) {
62					buf[i] |= (__u64)((w >> 5) & 1) << r[i]++;
63					t[i] = strobe;
64					u = v;
65				} else t[i] = 0;
66			}
67	} while (t[0] > 0 || t[1] > 0);
68
69	local_irq_restore(flags);
70
71	ret = 0;
72
73	for (i = 0; i < 2; i++) {
74
75		if (r[i] != COBRA_LENGTH) continue;
76
77		for (j = 0; j < COBRA_LENGTH && (buf[i] & 0x04104107f) ^ 0x041041040; j++)
78			buf[i] = (buf[i] >> 1) | ((__u64)(buf[i] & 1) << (COBRA_LENGTH - 1));
79
80		if (j < COBRA_LENGTH) ret |= (1 << i);
81
82		data[i] = ((buf[i] >>  7) & 0x000001f) | ((buf[i] >>  8) & 0x00003e0)
83			| ((buf[i] >>  9) & 0x0007c00) | ((buf[i] >> 10) & 0x00f8000)
84			| ((buf[i] >> 11) & 0x1f00000);
85
86	}
87
88	return ret;
89}
90
91static void cobra_poll(struct gameport *gameport)
92{
93	struct cobra *cobra = gameport_get_drvdata(gameport);
94	struct input_dev *dev;
95	unsigned int data[2];
96	int i, j, r;
97
98	cobra->reads++;
99
100	if ((r = cobra_read_packet(gameport, data)) != cobra->exists) {
101		cobra->bads++;
102		return;
103	}
104
105	for (i = 0; i < 2; i++)
106		if (cobra->exists & r & (1 << i)) {
107
108			dev = cobra->dev[i];
109
110			input_report_abs(dev, ABS_X, ((data[i] >> 4) & 1) - ((data[i] >> 3) & 1));
111			input_report_abs(dev, ABS_Y, ((data[i] >> 2) & 1) - ((data[i] >> 1) & 1));
112
113			for (j = 0; cobra_btn[j]; j++)
114				input_report_key(dev, cobra_btn[j], data[i] & (0x20 << j));
115
116			input_sync(dev);
117
118		}
119}
120
121static int cobra_open(struct input_dev *dev)
122{
123	struct cobra *cobra = input_get_drvdata(dev);
124
125	gameport_start_polling(cobra->gameport);
126	return 0;
127}
128
129static void cobra_close(struct input_dev *dev)
130{
131	struct cobra *cobra = input_get_drvdata(dev);
132
133	gameport_stop_polling(cobra->gameport);
134}
135
136static int cobra_connect(struct gameport *gameport, struct gameport_driver *drv)
137{
138	struct cobra *cobra;
139	struct input_dev *input_dev;
140	unsigned int data[2];
141	int i, j;
142	int err;
143
144	cobra = kzalloc(sizeof(struct cobra), GFP_KERNEL);
145	if (!cobra)
146		return -ENOMEM;
147
148	cobra->gameport = gameport;
149
150	gameport_set_drvdata(gameport, cobra);
151
152	err = gameport_open(gameport, drv, GAMEPORT_MODE_RAW);
153	if (err)
154		goto fail1;
155
156	cobra->exists = cobra_read_packet(gameport, data);
157
158	for (i = 0; i < 2; i++)
159		if ((cobra->exists >> i) & data[i] & 1) {
160			printk(KERN_WARNING "cobra.c: Device %d on %s has the Ext bit set. ID is: %d"
161				" Contact vojtech@ucw.cz\n", i, gameport->phys, (data[i] >> 2) & 7);
162			cobra->exists &= ~(1 << i);
163		}
164
165	if (!cobra->exists) {
166		err = -ENODEV;
167		goto fail2;
168	}
169
170	gameport_set_poll_handler(gameport, cobra_poll);
171	gameport_set_poll_interval(gameport, 20);
172
173	for (i = 0; i < 2; i++) {
174		if (~(cobra->exists >> i) & 1)
175			continue;
176
177		cobra->dev[i] = input_dev = input_allocate_device();
178		if (!input_dev) {
179			err = -ENOMEM;
180			goto fail3;
181		}
182
183		snprintf(cobra->phys[i], sizeof(cobra->phys[i]),
184			 "%s/input%d", gameport->phys, i);
185
186		input_dev->name = "Creative Labs Blaster GamePad Cobra";
187		input_dev->phys = cobra->phys[i];
188		input_dev->id.bustype = BUS_GAMEPORT;
189		input_dev->id.vendor = GAMEPORT_ID_VENDOR_CREATIVE;
190		input_dev->id.product = 0x0008;
191		input_dev->id.version = 0x0100;
192		input_dev->dev.parent = &gameport->dev;
193
194		input_set_drvdata(input_dev, cobra);
195
196		input_dev->open = cobra_open;
197		input_dev->close = cobra_close;
198
199		input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
200		input_set_abs_params(input_dev, ABS_X, -1, 1, 0, 0);
201		input_set_abs_params(input_dev, ABS_Y, -1, 1, 0, 0);
202		for (j = 0; cobra_btn[j]; j++)
203			set_bit(cobra_btn[j], input_dev->keybit);
204
205		err = input_register_device(cobra->dev[i]);
206		if (err)
207			goto fail4;
208	}
209
210	return 0;
211
212 fail4:	input_free_device(cobra->dev[i]);
213 fail3:	while (--i >= 0)
214		if (cobra->dev[i])
215			input_unregister_device(cobra->dev[i]);
216 fail2:	gameport_close(gameport);
217 fail1:	gameport_set_drvdata(gameport, NULL);
218	kfree(cobra);
219	return err;
220}
221
222static void cobra_disconnect(struct gameport *gameport)
223{
224	struct cobra *cobra = gameport_get_drvdata(gameport);
225	int i;
226
227	for (i = 0; i < 2; i++)
228		if ((cobra->exists >> i) & 1)
229			input_unregister_device(cobra->dev[i]);
230	gameport_close(gameport);
231	gameport_set_drvdata(gameport, NULL);
232	kfree(cobra);
233}
234
235static struct gameport_driver cobra_drv = {
236	.driver		= {
237		.name	= "cobra",
238	},
239	.description	= DRIVER_DESC,
240	.connect	= cobra_connect,
241	.disconnect	= cobra_disconnect,
242};
243
244module_gameport_driver(cobra_drv);
245