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 
19 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
20 MODULE_DESCRIPTION(DRIVER_DESC);
21 MODULE_LICENSE("GPL");
22 
23 #define COBRA_MAX_STROBE	45	/* 45 us max wait for first strobe */
24 #define COBRA_LENGTH		36
25 
26 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 };
27 
28 struct 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 
cobra_read_packet(struct gameport * gameport,unsigned int * data)37 static 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 
cobra_poll(struct gameport * gameport)91 static 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 
cobra_open(struct input_dev * dev)121 static 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 
cobra_close(struct input_dev * dev)129 static 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 
cobra_connect(struct gameport * gameport,struct gameport_driver * drv)136 static 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 
cobra_disconnect(struct gameport * gameport)222 static 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 
235 static 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 
244 module_gameport_driver(cobra_drv);
245