xref: /freebsd/sys/dev/smbus/smb.c (revision 405c3050f102b8c74782f0366c8ead927bd07b68)
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 devclass_t smb_devclass;
61 
62 static device_method_t smb_methods[] = {
63 	/* device interface */
64 	DEVMETHOD(device_identify,	smb_identify),
65 	DEVMETHOD(device_probe,		smb_probe),
66 	DEVMETHOD(device_attach,	smb_attach),
67 	DEVMETHOD(device_detach,	smb_detach),
68 
69 	/* smbus interface */
70 	DEVMETHOD(smbus_intr,		smbus_generic_intr),
71 
72 	{ 0, 0 }
73 };
74 
75 static driver_t smb_driver = {
76 	"smb",
77 	smb_methods,
78 	sizeof(struct smb_softc),
79 };
80 
81 static	d_ioctl_t	smbioctl;
82 
83 static struct cdevsw smb_cdevsw = {
84 	.d_version =	D_VERSION,
85 	.d_flags =	D_TRACKCLOSE,
86 	.d_ioctl =	smbioctl,
87 	.d_name =	"smb",
88 };
89 
90 static void
91 smb_identify(driver_t *driver, device_t parent)
92 {
93 
94 	if (device_find_child(parent, "smb", -1) == NULL)
95 		BUS_ADD_CHILD(parent, 0, "smb", -1);
96 }
97 
98 static int
99 smb_probe(device_t dev)
100 {
101 	if (smbus_get_addr(dev) != -1)
102 		return (ENXIO);
103 
104 	device_set_desc(dev, "SMBus generic I/O");
105 	return (BUS_PROBE_NOWILDCARD);
106 }
107 
108 static int
109 smb_attach(device_t dev)
110 {
111 	struct smb_softc *sc;
112 	struct make_dev_args mda;
113 	int error;
114 
115 	sc = device_get_softc(dev);
116 	sc->sc_dev = dev;
117 
118 	make_dev_args_init(&mda);
119 	mda.mda_devsw = &smb_cdevsw;
120 	mda.mda_unit = device_get_unit(dev);
121 	mda.mda_uid = UID_ROOT;
122 	mda.mda_gid = GID_WHEEL;
123 	mda.mda_mode = 0600;
124 	mda.mda_si_drv1 = sc;
125 	error = make_dev_s(&mda, &sc->sc_devnode, "smb%d", mda.mda_unit);
126 	return (error);
127 }
128 
129 static int
130 smb_detach(device_t dev)
131 {
132 	struct smb_softc *sc;
133 
134 	sc = device_get_softc(dev);
135 	destroy_dev(sc->sc_devnode);
136 	return (0);
137 }
138 
139 static int
140 smbioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td)
141 {
142 	char buf[SMB_MAXBLOCKSIZE];
143 	device_t parent;
144 	struct smbcmd *s = (struct smbcmd *)data;
145 	struct smb_softc *sc = dev->si_drv1;
146 	device_t smbdev = sc->sc_dev;
147 	int error;
148 	int unit;
149 	u_char bcount;
150 
151 	/*
152 	 * If a specific slave device is being used, override any passed-in
153 	 * slave.
154 	 */
155 	unit = dev2unit(dev);
156 	if (unit & 0x0400)
157 		s->slave = unit & 0x03ff;
158 
159 	parent = device_get_parent(smbdev);
160 
161 	/* Make sure that LSB bit is cleared. */
162 	if (s->slave & 0x1)
163 		return (EINVAL);
164 
165 	/* Allocate the bus. */
166 	if ((error = smbus_request_bus(parent, smbdev,
167 			(flags & O_NONBLOCK) ? SMB_DONTWAIT : (SMB_WAIT | SMB_INTR))))
168 		return (error);
169 
170 	switch (cmd) {
171 	case SMB_QUICK_WRITE:
172 		error = smbus_error(smbus_quick(parent, s->slave, SMB_QWRITE));
173 		break;
174 
175 	case SMB_QUICK_READ:
176 		error = smbus_error(smbus_quick(parent, s->slave, SMB_QREAD));
177 		break;
178 
179 	case SMB_SENDB:
180 		error = smbus_error(smbus_sendb(parent, s->slave, s->cmd));
181 		break;
182 
183 	case SMB_RECVB:
184 		error = smbus_error(smbus_recvb(parent, s->slave, &s->cmd));
185 		break;
186 
187 	case SMB_WRITEB:
188 		error = smbus_error(smbus_writeb(parent, s->slave, s->cmd,
189 						s->wdata.byte));
190 		break;
191 
192 	case SMB_WRITEW:
193 		error = smbus_error(smbus_writew(parent, s->slave,
194 						s->cmd, s->wdata.word));
195 		break;
196 
197 	case SMB_OLD_READB:
198 	case SMB_READB:
199 		/* NB: for SMB_OLD_READB the read data goes to rbuf only. */
200 		error = smbus_error(smbus_readb(parent, s->slave, s->cmd,
201 		    &s->rdata.byte));
202 		if (error)
203 			break;
204 		if (s->rbuf && s->rcount >= 1) {
205 			error = copyout(&s->rdata.byte, s->rbuf, 1);
206 			s->rcount = 1;
207 		}
208 		break;
209 
210 	case SMB_OLD_READW:
211 	case SMB_READW:
212 		/* NB: for SMB_OLD_READW the read data goes to rbuf only. */
213 		error = smbus_error(smbus_readw(parent, s->slave, s->cmd,
214 		    &s->rdata.word));
215 		if (error)
216 			break;
217 		if (s->rbuf && s->rcount >= 2) {
218 			buf[0] = (u_char)s->rdata.word;
219 			buf[1] = (u_char)(s->rdata.word >> 8);
220 			error = copyout(buf, s->rbuf, 2);
221 			s->rcount = 2;
222 		}
223 		break;
224 
225 	case SMB_OLD_PCALL:
226 	case SMB_PCALL:
227 		/* NB: for SMB_OLD_PCALL the read data goes to rbuf only. */
228 		error = smbus_error(smbus_pcall(parent, s->slave, s->cmd,
229 		    s->wdata.word, &s->rdata.word));
230 		if (error)
231 			break;
232 		if (s->rbuf && s->rcount >= 2) {
233 			buf[0] = (u_char)s->rdata.word;
234 			buf[1] = (u_char)(s->rdata.word >> 8);
235 			error = copyout(buf, s->rbuf, 2);
236 			s->rcount = 2;
237 		}
238 
239 		break;
240 
241 	case SMB_BWRITE:
242 		if (s->wcount < 0) {
243 			error = EINVAL;
244 			break;
245 		}
246 		if (s->wcount > SMB_MAXBLOCKSIZE)
247 			s->wcount = SMB_MAXBLOCKSIZE;
248 		if (s->wcount)
249 			error = copyin(s->wbuf, buf, s->wcount);
250 		if (error)
251 			break;
252 		error = smbus_error(smbus_bwrite(parent, s->slave, s->cmd,
253 		    s->wcount, buf));
254 		break;
255 
256 	case SMB_BREAD:
257 		if (s->rcount < 0) {
258 			error = EINVAL;
259 			break;
260 		}
261 		if (s->rcount > SMB_MAXBLOCKSIZE)
262 			s->rcount = SMB_MAXBLOCKSIZE;
263 		error = smbus_error(smbus_bread(parent, s->slave, s->cmd,
264 		    &bcount, buf));
265 		if (error)
266 			break;
267 		if (s->rcount > bcount)
268 			s->rcount = bcount;
269 		error = copyout(buf, s->rbuf, s->rcount);
270 		break;
271 
272 	default:
273 		error = ENOTTY;
274 	}
275 
276 	smbus_release_bus(parent, smbdev);
277 
278 	return (error);
279 }
280 
281 DRIVER_MODULE(smb, smbus, smb_driver, smb_devclass, 0, 0);
282 MODULE_DEPEND(smb, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER);
283 MODULE_VERSION(smb, 1);
284