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 /*
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/gameport.h>
17 #include <linux/input.h>
18 #include <linux/jiffies.h>
19 
20 #define DRIVER_DESC	"Creative Labs Blaster GamePad Cobra driver"
21 
22 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
23 MODULE_DESCRIPTION(DRIVER_DESC);
24 MODULE_LICENSE("GPL");
25 
26 #define COBRA_MAX_STROBE	45	/* 45 us max wait for first strobe */
27 #define COBRA_LENGTH		36
28 
29 static 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 };
30 
31 struct cobra {
32 	struct gameport *gameport;
33 	struct input_dev *dev[2];
34 	int reads;
35 	int bads;
36 	unsigned char exists;
37 	char phys[2][32];
38 };
39 
cobra_read_packet(struct gameport * gameport,unsigned int * data)40 static unsigned char cobra_read_packet(struct gameport *gameport, unsigned int *data)
41 {
42 	unsigned long flags;
43 	unsigned char u, v, w;
44 	__u64 buf[2];
45 	int r[2], t[2];
46 	int i, j, ret;
47 
48 	int strobe = gameport_time(gameport, COBRA_MAX_STROBE);
49 
50 	for (i = 0; i < 2; i++) {
51 		r[i] = buf[i] = 0;
52 		t[i] = COBRA_MAX_STROBE;
53 	}
54 
55 	local_irq_save(flags);
56 
57 	u = gameport_read(gameport);
58 
59 	do {
60 		t[0]--; t[1]--;
61 		v = gameport_read(gameport);
62 		for (i = 0, w = u ^ v; i < 2 && w; i++, w >>= 2)
63 			if (w & 0x30) {
64 				if ((w & 0x30) < 0x30 && r[i] < COBRA_LENGTH && t[i] > 0) {
65 					buf[i] |= (__u64)((w >> 5) & 1) << r[i]++;
66 					t[i] = strobe;
67 					u = v;
68 				} else t[i] = 0;
69 			}
70 	} while (t[0] > 0 || t[1] > 0);
71 
72 	local_irq_restore(flags);
73 
74 	ret = 0;
75 
76 	for (i = 0; i < 2; i++) {
77 
78 		if (r[i] != COBRA_LENGTH) continue;
79 
80 		for (j = 0; j < COBRA_LENGTH && (buf[i] & 0x04104107f) ^ 0x041041040; j++)
81 			buf[i] = (buf[i] >> 1) | ((__u64)(buf[i] & 1) << (COBRA_LENGTH - 1));
82 
83 		if (j < COBRA_LENGTH) ret |= (1 << i);
84 
85 		data[i] = ((buf[i] >>  7) & 0x000001f) | ((buf[i] >>  8) & 0x00003e0)
86 			| ((buf[i] >>  9) & 0x0007c00) | ((buf[i] >> 10) & 0x00f8000)
87 			| ((buf[i] >> 11) & 0x1f00000);
88 
89 	}
90 
91 	return ret;
92 }
93 
cobra_poll(struct gameport * gameport)94 static void cobra_poll(struct gameport *gameport)
95 {
96 	struct cobra *cobra = gameport_get_drvdata(gameport);
97 	struct input_dev *dev;
98 	unsigned int data[2];
99 	int i, j, r;
100 
101 	cobra->reads++;
102 
103 	if ((r = cobra_read_packet(gameport, data)) != cobra->exists) {
104 		cobra->bads++;
105 		return;
106 	}
107 
108 	for (i = 0; i < 2; i++)
109 		if (cobra->exists & r & (1 << i)) {
110 
111 			dev = cobra->dev[i];
112 
113 			input_report_abs(dev, ABS_X, ((data[i] >> 4) & 1) - ((data[i] >> 3) & 1));
114 			input_report_abs(dev, ABS_Y, ((data[i] >> 2) & 1) - ((data[i] >> 1) & 1));
115 
116 			for (j = 0; cobra_btn[j]; j++)
117 				input_report_key(dev, cobra_btn[j], data[i] & (0x20 << j));
118 
119 			input_sync(dev);
120 
121 		}
122 }
123 
cobra_open(struct input_dev * dev)124 static int cobra_open(struct input_dev *dev)
125 {
126 	struct cobra *cobra = input_get_drvdata(dev);
127 
128 	gameport_start_polling(cobra->gameport);
129 	return 0;
130 }
131 
cobra_close(struct input_dev * dev)132 static void cobra_close(struct input_dev *dev)
133 {
134 	struct cobra *cobra = input_get_drvdata(dev);
135 
136 	gameport_stop_polling(cobra->gameport);
137 }
138 
cobra_connect(struct gameport * gameport,struct gameport_driver * drv)139 static int cobra_connect(struct gameport *gameport, struct gameport_driver *drv)
140 {
141 	struct cobra *cobra;
142 	struct input_dev *input_dev;
143 	unsigned int data[2];
144 	int i, j;
145 	int err;
146 
147 	cobra = kzalloc(sizeof(struct cobra), GFP_KERNEL);
148 	if (!cobra)
149 		return -ENOMEM;
150 
151 	cobra->gameport = gameport;
152 
153 	gameport_set_drvdata(gameport, cobra);
154 
155 	err = gameport_open(gameport, drv, GAMEPORT_MODE_RAW);
156 	if (err)
157 		goto fail1;
158 
159 	cobra->exists = cobra_read_packet(gameport, data);
160 
161 	for (i = 0; i < 2; i++)
162 		if ((cobra->exists >> i) & data[i] & 1) {
163 			printk(KERN_WARNING "cobra.c: Device %d on %s has the Ext bit set. ID is: %d"
164 				" Contact vojtech@ucw.cz\n", i, gameport->phys, (data[i] >> 2) & 7);
165 			cobra->exists &= ~(1 << i);
166 		}
167 
168 	if (!cobra->exists) {
169 		err = -ENODEV;
170 		goto fail2;
171 	}
172 
173 	gameport_set_poll_handler(gameport, cobra_poll);
174 	gameport_set_poll_interval(gameport, 20);
175 
176 	for (i = 0; i < 2; i++) {
177 		if (~(cobra->exists >> i) & 1)
178 			continue;
179 
180 		cobra->dev[i] = input_dev = input_allocate_device();
181 		if (!input_dev) {
182 			err = -ENOMEM;
183 			goto fail3;
184 		}
185 
186 		snprintf(cobra->phys[i], sizeof(cobra->phys[i]),
187 			 "%s/input%d", gameport->phys, i);
188 
189 		input_dev->name = "Creative Labs Blaster GamePad Cobra";
190 		input_dev->phys = cobra->phys[i];
191 		input_dev->id.bustype = BUS_GAMEPORT;
192 		input_dev->id.vendor = GAMEPORT_ID_VENDOR_CREATIVE;
193 		input_dev->id.product = 0x0008;
194 		input_dev->id.version = 0x0100;
195 		input_dev->dev.parent = &gameport->dev;
196 
197 		input_set_drvdata(input_dev, cobra);
198 
199 		input_dev->open = cobra_open;
200 		input_dev->close = cobra_close;
201 
202 		input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
203 		input_set_abs_params(input_dev, ABS_X, -1, 1, 0, 0);
204 		input_set_abs_params(input_dev, ABS_Y, -1, 1, 0, 0);
205 		for (j = 0; cobra_btn[j]; j++)
206 			set_bit(cobra_btn[j], input_dev->keybit);
207 
208 		err = input_register_device(cobra->dev[i]);
209 		if (err)
210 			goto fail4;
211 	}
212 
213 	return 0;
214 
215  fail4:	input_free_device(cobra->dev[i]);
216  fail3:	while (--i >= 0)
217 		if (cobra->dev[i])
218 			input_unregister_device(cobra->dev[i]);
219  fail2:	gameport_close(gameport);
220  fail1:	gameport_set_drvdata(gameport, NULL);
221 	kfree(cobra);
222 	return err;
223 }
224 
cobra_disconnect(struct gameport * gameport)225 static void cobra_disconnect(struct gameport *gameport)
226 {
227 	struct cobra *cobra = gameport_get_drvdata(gameport);
228 	int i;
229 
230 	for (i = 0; i < 2; i++)
231 		if ((cobra->exists >> i) & 1)
232 			input_unregister_device(cobra->dev[i]);
233 	gameport_close(gameport);
234 	gameport_set_drvdata(gameport, NULL);
235 	kfree(cobra);
236 }
237 
238 static struct gameport_driver cobra_drv = {
239 	.driver		= {
240 		.name	= "cobra",
241 	},
242 	.description	= DRIVER_DESC,
243 	.connect	= cobra_connect,
244 	.disconnect	= cobra_disconnect,
245 };
246 
247 module_gameport_driver(cobra_drv);
248