xref: /openbsd/sys/dev/sun/sunms.c (revision 4bdff4be)
1 /*	$OpenBSD: sunms.c,v 1.3 2022/01/09 05:43:00 jsg Exp $	*/
2 
3 /*
4  * Copyright (c) 2002, 2009, Miodrag Vallat
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 /*
29  * Common Sun mouse handling code.
30  *
31  * This code supports 3- and 5- byte Mouse Systems protocols, and speeds of
32  * 1200, 4800 and 9600 bps.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/conf.h>
38 #include <sys/device.h>
39 #include <sys/ioctl.h>
40 #include <sys/kernel.h>
41 #include <sys/proc.h>
42 #include <sys/time.h>
43 #include <sys/timeout.h>
44 
45 #include <dev/wscons/wsconsio.h>
46 #include <dev/wscons/wsmousevar.h>
47 
48 #include <dev/sun/sunmsvar.h>
49 
50 void
51 sunms_attach(struct sunms_softc *sc, const struct wsmouse_accessops *ao)
52 {
53 	struct wsmousedev_attach_args a;
54 
55 	printf("\n");
56 
57 	/* Initialize state machine. */
58 	sc->sc_state = STATE_PROBING;
59 	sc->sc_bps = INIT_SPEED;
60 	timeout_set(&sc->sc_abort_tmo, sunms_abort_input, sc);
61 
62 	/*
63 	 * Note that it doesn't matter if a long time elapses between this
64 	 * and the moment interrupts are enabled, as we either have the
65 	 * right speed, and will switch to decode state, or get a break
66 	 * or a framing error, causing an immediate speed change.
67 	 */
68 	getmicrotime(&sc->sc_lastbpschange);
69 
70 	a.accessops = ao;
71 	a.accesscookie = sc;
72 	sc->sc_wsmousedev = config_found(&sc->sc_dev, &a, wsmousedevprint);
73 }
74 
75 int
76 sunms_ioctl(void *v, u_long cmd, caddr_t data, int flag, struct proc *p)
77 {
78 #if 0
79 	struct sunms_softc *sc = v;
80 #endif
81 
82 	switch (cmd) {
83 	case WSMOUSEIO_GTYPE:
84 		*(u_int *)data = WSMOUSE_TYPE_SUN;
85 		break;
86 
87 	default:
88 		return -1;
89 	}
90 
91 	return 0;
92 }
93 
94 /*
95  * Reinitialize the line to a different speed.  Invoked at spltty().
96  */
97 void
98 sunms_speed_change(struct sunms_softc *sc)
99 {
100 	uint bps;
101 
102 	switch (sc->sc_bps) {
103 	default:
104 	case 9600:
105 		bps = 4800;
106 		break;
107 	case 4800:
108 		bps = 1200;
109 		break;
110 	case 1200:
111 		bps = 9600;
112 		break;
113 	}
114 
115 #ifdef DEBUG
116 	printf("%s: %d bps\n", sc->sc_dev.dv_xname, bps);
117 #endif
118 	microtime(&sc->sc_lastbpschange);
119 
120 	(*sc->sc_speed_change)(sc, bps);
121 	sc->sc_state = STATE_PROBING;
122 	sc->sc_bps = bps;
123 	sc->sc_brk = 0;
124 	timeout_del(&sc->sc_abort_tmo);
125 }
126 
127 /*
128  * Process actual mouse data.  Invoked at spltty().
129  */
130 void
131 sunms_input(struct sunms_softc *sc, int c)
132 {
133 	struct timeval curtime;
134 
135 	if (sc->sc_wsmousedev == NULL)
136 		return;	/* why bother */
137 
138 	if (sc->sc_state == STATE_RATE_CHANGE)
139 		return;	/* not ready yet */
140 
141 	/*
142 	 * If we have changed speed recently, ignore data for a few
143 	 * milliseconds to make sure that either we'll detect the speed
144 	 * is still not correct, or discard potential noise resulting
145 	 * from the speed change.
146 	 */
147 	if (sc->sc_state == STATE_PROBING) {
148 		microtime(&curtime);
149 		timersub(&curtime, &sc->sc_lastbpschange, &curtime);
150 		if (curtime.tv_sec != 0 ||
151 		    curtime.tv_usec >= 200 * 1000) {
152 			sc->sc_state = STATE_DECODING;
153 			sc->sc_byteno = -1;
154 		} else
155 			return;
156 	}
157 
158 	/*
159 	 * The Sun mice use either 3 byte or 5 byte packets. The
160 	 * first byte of each packet has the topmost bit set;
161 	 * however motion parts of the packet may have the topmost
162 	 * bit set too; so we only check for a first byte pattern
163 	 * when we are not currently processing a packet.
164 	 */
165 	if (sc->sc_byteno < 0) {
166 		if (ISSET(c, 0x80) && !ISSET(c, 0x30))
167 			sc->sc_byteno = 0;
168 		else
169 			return;
170 	}
171 
172 	switch (sc->sc_byteno) {
173 	case 0:
174 		/*
175 		 * First packet has bit 7 set; bits 0-2 are button states,
176 		 * and bit 3 is set if it is a short (3 byte) packet.
177 		 * On the Tadpole SPARCbook, mice connected to the external
178 		 * connector will also have bit 6 set to allow it to be
179 		 * differentiated from the onboard pointer.
180 		 */
181 		sc->sc_pktlen = ISSET(c, 0x08) ? 3 : 5;
182 		sc->sc_mb = 0;
183 		if (!ISSET(c, 1 << 2))	/* left button */
184 			sc->sc_mb |= 1 << 0;
185 		if (!ISSET(c, 1 << 1))	/* middle button */
186 			sc->sc_mb |= 1 << 1;
187 		if (!ISSET(c, 1 << 0))	/* right button */
188 			sc->sc_mb |= 1 << 2;
189 		sc->sc_byteno++;
190 
191 		/*
192 		 * In case we do not receive the whole packet, we need
193 		 * to be able to reset sc_byteno.
194 		 *
195 		 * At 1200bps 8N2, a five byte packet will span 50 bits
196 		 * and thus will transmit in 1/24 second, or about 42ms.
197 		 *
198 		 * A reset timeout of 100ms will be more than enough.
199 		 */
200 		timeout_add_msec(&sc->sc_abort_tmo, 100);
201 
202 		break;
203 	case 1:
204 	case 3:
205 		/*
206 		 * Following bytes contain signed 7 bit X, then Y deltas.
207 		 * Short packets only have one set of deltas (and are
208 		 * thus usually used on 4800 baud mice).
209 		 */
210 		sc->sc_dx += (int8_t)c;
211 		sc->sc_byteno++;
212 		break;
213 	case 2:
214 	case 4:
215 		sc->sc_dy += (int8_t)c;
216 		sc->sc_byteno++;
217 		break;
218 	}
219 
220 	if (sc->sc_byteno == sc->sc_pktlen) {
221 		timeout_del(&sc->sc_abort_tmo);
222 		sc->sc_byteno = -1;
223 		WSMOUSE_INPUT(sc->sc_wsmousedev,
224 		    sc->sc_mb, sc->sc_dx, sc->sc_dy, 0, 0);
225 		sc->sc_dx = sc->sc_dy = 0;
226 	}
227 }
228 
229 void
230 sunms_abort_input(void *v)
231 {
232 	struct sunms_softc *sc = v;
233 	int s;
234 
235 #ifdef DEBUG
236 	printf("aborting incomplete packet\n");
237 #endif
238 	s = spltty();
239 	sc->sc_byteno = -1;
240 	splx(s);
241 }
242