xref: /freebsd/sys/dev/smbus/smb.c (revision 8eb2bee6c0f4957c6c1cea826e59cda4d18a2a64)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1998, 2001 Nicolas Souchu
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 AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/systm.h>
34 #include <sys/module.h>
35 #include <sys/bus.h>
36 #include <sys/conf.h>
37 #include <sys/uio.h>
38 #include <sys/fcntl.h>
39 
40 #include <dev/smbus/smbconf.h>
41 #include <dev/smbus/smbus.h>
42 #include <dev/smbus/smb.h>
43 
44 #include "smbus_if.h"
45 
46 #define SMB_OLD_READB	_IOW('i', 7, struct smbcmd)
47 #define SMB_OLD_READW	_IOW('i', 8, struct smbcmd)
48 #define SMB_OLD_PCALL	_IOW('i', 9, struct smbcmd)
49 
50 struct smb_softc {
51 	device_t sc_dev;
52 	struct cdev *sc_devnode;
53 };
54 
55 static void smb_identify(driver_t *driver, device_t parent);
56 static int smb_probe(device_t);
57 static int smb_attach(device_t);
58 static int smb_detach(device_t);
59 
60 static device_method_t smb_methods[] = {
61 	/* device interface */
62 	DEVMETHOD(device_identify,	smb_identify),
63 	DEVMETHOD(device_probe,		smb_probe),
64 	DEVMETHOD(device_attach,	smb_attach),
65 	DEVMETHOD(device_detach,	smb_detach),
66 
67 	/* smbus interface */
68 	DEVMETHOD(smbus_intr,		smbus_generic_intr),
69 	{ 0, 0 }
70 };
71 
72 static driver_t smb_driver = {
73 	"smb",
74 	smb_methods,
75 	sizeof(struct smb_softc),
76 };
77 
78 static	d_ioctl_t	smbioctl;
79 
80 static struct cdevsw smb_cdevsw = {
81 	.d_version =	D_VERSION,
82 	.d_flags =	D_TRACKCLOSE,
83 	.d_ioctl =	smbioctl,
84 	.d_name =	"smb",
85 };
86 
87 static void
88 smb_identify(driver_t *driver, device_t parent)
89 {
90 
91 	if (device_find_child(parent, "smb", -1) == NULL)
92 		BUS_ADD_CHILD(parent, 0, "smb", -1);
93 }
94 
95 static int
96 smb_probe(device_t dev)
97 {
98 	if (smbus_get_addr(dev) != -1)
99 		return (ENXIO);
100 
101 	device_set_desc(dev, "SMBus generic I/O");
102 	return (BUS_PROBE_NOWILDCARD);
103 }
104 
105 static int
106 smb_attach(device_t dev)
107 {
108 	struct smb_softc *sc;
109 	struct make_dev_args mda;
110 	int error;
111 
112 	sc = device_get_softc(dev);
113 	sc->sc_dev = dev;
114 
115 	make_dev_args_init(&mda);
116 	mda.mda_devsw = &smb_cdevsw;
117 	mda.mda_unit = device_get_unit(dev);
118 	mda.mda_uid = UID_ROOT;
119 	mda.mda_gid = GID_WHEEL;
120 	mda.mda_mode = 0600;
121 	mda.mda_si_drv1 = sc;
122 	error = make_dev_s(&mda, &sc->sc_devnode, "smb%d", mda.mda_unit);
123 	return (error);
124 }
125 
126 static int
127 smb_detach(device_t dev)
128 {
129 	struct smb_softc *sc;
130 
131 	sc = device_get_softc(dev);
132 	destroy_dev(sc->sc_devnode);
133 	return (0);
134 }
135 
136 static int
137 smbioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td)
138 {
139 	char buf[SMB_MAXBLOCKSIZE];
140 	device_t parent;
141 	struct smbcmd *s = (struct smbcmd *)data;
142 	struct smb_softc *sc = dev->si_drv1;
143 	device_t smbdev = sc->sc_dev;
144 	int error;
145 	int unit;
146 	u_char bcount;
147 
148 	/*
149 	 * If a specific slave device is being used, override any passed-in
150 	 * slave.
151 	 */
152 	unit = dev2unit(dev);
153 	if (unit & 0x0400)
154 		s->slave = unit & 0x03ff;
155 
156 	parent = device_get_parent(smbdev);
157 
158 	/* Make sure that LSB bit is cleared. */
159 	if (s->slave & 0x1)
160 		return (EINVAL);
161 
162 	/* Allocate the bus. */
163 	if ((error = smbus_request_bus(parent, smbdev,
164 			(flags & O_NONBLOCK) ? SMB_DONTWAIT : (SMB_WAIT | SMB_INTR))))
165 		return (error);
166 
167 	switch (cmd) {
168 	case SMB_QUICK_WRITE:
169 		error = smbus_error(smbus_quick(parent, s->slave, SMB_QWRITE));
170 		break;
171 
172 	case SMB_QUICK_READ:
173 		error = smbus_error(smbus_quick(parent, s->slave, SMB_QREAD));
174 		break;
175 
176 	case SMB_SENDB:
177 		error = smbus_error(smbus_sendb(parent, s->slave, s->cmd));
178 		break;
179 
180 	case SMB_RECVB:
181 		error = smbus_error(smbus_recvb(parent, s->slave, &s->cmd));
182 		break;
183 
184 	case SMB_WRITEB:
185 		error = smbus_error(smbus_writeb(parent, s->slave, s->cmd,
186 						s->wdata.byte));
187 		break;
188 
189 	case SMB_WRITEW:
190 		error = smbus_error(smbus_writew(parent, s->slave,
191 						s->cmd, s->wdata.word));
192 		break;
193 
194 	case SMB_OLD_READB:
195 	case SMB_READB:
196 		/* NB: for SMB_OLD_READB the read data goes to rbuf only. */
197 		error = smbus_error(smbus_readb(parent, s->slave, s->cmd,
198 		    &s->rdata.byte));
199 		if (error)
200 			break;
201 		if (s->rbuf && s->rcount >= 1) {
202 			error = copyout(&s->rdata.byte, s->rbuf, 1);
203 			s->rcount = 1;
204 		}
205 		break;
206 
207 	case SMB_OLD_READW:
208 	case SMB_READW:
209 		/* NB: for SMB_OLD_READW the read data goes to rbuf only. */
210 		error = smbus_error(smbus_readw(parent, s->slave, s->cmd,
211 		    &s->rdata.word));
212 		if (error)
213 			break;
214 		if (s->rbuf && s->rcount >= 2) {
215 			buf[0] = (u_char)s->rdata.word;
216 			buf[1] = (u_char)(s->rdata.word >> 8);
217 			error = copyout(buf, s->rbuf, 2);
218 			s->rcount = 2;
219 		}
220 		break;
221 
222 	case SMB_OLD_PCALL:
223 	case SMB_PCALL:
224 		/* NB: for SMB_OLD_PCALL the read data goes to rbuf only. */
225 		error = smbus_error(smbus_pcall(parent, s->slave, s->cmd,
226 		    s->wdata.word, &s->rdata.word));
227 		if (error)
228 			break;
229 		if (s->rbuf && s->rcount >= 2) {
230 			buf[0] = (u_char)s->rdata.word;
231 			buf[1] = (u_char)(s->rdata.word >> 8);
232 			error = copyout(buf, s->rbuf, 2);
233 			s->rcount = 2;
234 		}
235 
236 		break;
237 
238 	case SMB_BWRITE:
239 		if (s->wcount < 0) {
240 			error = EINVAL;
241 			break;
242 		}
243 		if (s->wcount > SMB_MAXBLOCKSIZE)
244 			s->wcount = SMB_MAXBLOCKSIZE;
245 		if (s->wcount)
246 			error = copyin(s->wbuf, buf, s->wcount);
247 		if (error)
248 			break;
249 		error = smbus_error(smbus_bwrite(parent, s->slave, s->cmd,
250 		    s->wcount, buf));
251 		break;
252 
253 	case SMB_BREAD:
254 		if (s->rcount < 0) {
255 			error = EINVAL;
256 			break;
257 		}
258 		if (s->rcount > SMB_MAXBLOCKSIZE)
259 			s->rcount = SMB_MAXBLOCKSIZE;
260 		error = smbus_error(smbus_bread(parent, s->slave, s->cmd,
261 		    &bcount, buf));
262 		if (error)
263 			break;
264 		if (s->rcount > bcount)
265 			s->rcount = bcount;
266 		error = copyout(buf, s->rbuf, s->rcount);
267 		break;
268 
269 	default:
270 		error = ENOTTY;
271 	}
272 
273 	smbus_release_bus(parent, smbdev);
274 
275 	return (error);
276 }
277 
278 DRIVER_MODULE(smb, smbus, smb_driver, 0, 0);
279 MODULE_DEPEND(smb, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER);
280 MODULE_VERSION(smb, 1);
281