xref: /freebsd/sys/dev/smbus/smb.c (revision 3fe92528afe8313fecf48822dde74bad5e380f48)
1 /*-
2  * Copyright (c) 1998, 2001 Nicolas Souchu
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <sys/param.h>
30 #include <sys/kernel.h>
31 #include <sys/systm.h>
32 #include <sys/module.h>
33 #include <sys/bus.h>
34 #include <sys/conf.h>
35 #include <sys/uio.h>
36 #include <sys/fcntl.h>
37 
38 #include <dev/smbus/smbconf.h>
39 #include <dev/smbus/smbus.h>
40 #include <dev/smbus/smb.h>
41 
42 #include "smbus_if.h"
43 
44 #define BUFSIZE 1024
45 
46 struct smb_softc {
47 
48 	int sc_count;			/* >0 if device opened */
49 	struct cdev *sc_devnode;
50 };
51 
52 #define IIC_SOFTC(unit) \
53 	((struct smb_softc *)devclass_get_softc(smb_devclass, (unit)))
54 
55 #define IIC_DEVICE(unit) \
56 	(devclass_get_device(smb_devclass, (unit)))
57 
58 static void smb_identify(driver_t *driver, device_t parent);
59 static int smb_probe(device_t);
60 static int smb_attach(device_t);
61 static int smb_detach(device_t);
62 
63 static devclass_t smb_devclass;
64 
65 static device_method_t smb_methods[] = {
66 	/* device interface */
67 	DEVMETHOD(device_identify,	smb_identify),
68 	DEVMETHOD(device_probe,		smb_probe),
69 	DEVMETHOD(device_attach,	smb_attach),
70 	DEVMETHOD(device_detach,	smb_detach),
71 
72 	/* smbus interface */
73 	DEVMETHOD(smbus_intr,		smbus_generic_intr),
74 
75 	{ 0, 0 }
76 };
77 
78 static driver_t smb_driver = {
79 	"smb",
80 	smb_methods,
81 	sizeof(struct smb_softc),
82 };
83 
84 static	d_open_t	smbopen;
85 static	d_close_t	smbclose;
86 static	d_ioctl_t	smbioctl;
87 
88 static struct cdevsw smb_cdevsw = {
89 	.d_version =	D_VERSION,
90 	.d_flags =	D_NEEDGIANT,
91 	.d_open =	smbopen,
92 	.d_close =	smbclose,
93 	.d_ioctl =	smbioctl,
94 	.d_name =	"smb",
95 };
96 
97 static void
98 smb_identify(driver_t *driver, device_t parent)
99 {
100 
101 	if (device_find_child(parent, "smb", -1) == NULL)
102 		BUS_ADD_CHILD(parent, 0, "smb", -1);
103 }
104 
105 static int
106 smb_probe(device_t dev)
107 {
108 	device_set_desc(dev, "SMBus generic I/O");
109 
110 	return (0);
111 }
112 
113 static int
114 smb_attach(device_t dev)
115 {
116 	struct smb_softc *sc = (struct smb_softc *)device_get_softc(dev);
117 
118 	if (!sc)
119 		return (ENOMEM);
120 
121 	bzero(sc, sizeof(struct smb_softc *));
122 
123 	sc->sc_devnode = make_dev(&smb_cdevsw, device_get_unit(dev),
124 			UID_ROOT, GID_WHEEL,
125 			0600, "smb%d", device_get_unit(dev));
126 
127 	return (0);
128 }
129 
130 static int
131 smb_detach(device_t dev)
132 {
133 	struct smb_softc *sc = (struct smb_softc *)device_get_softc(dev);
134 
135 	if (sc->sc_devnode)
136 		destroy_dev(sc->sc_devnode);
137 
138 	return (0);
139 }
140 
141 static int
142 smbopen (struct cdev *dev, int flags, int fmt, struct thread *td)
143 {
144 	struct smb_softc *sc = IIC_SOFTC(minor(dev));
145 
146 	if (sc == NULL)
147 		return (ENXIO);
148 
149 	if (sc->sc_count != 0)
150 		return (EBUSY);
151 
152 	sc->sc_count++;
153 
154 	return (0);
155 }
156 
157 static int
158 smbclose(struct cdev *dev, int flags, int fmt, struct thread *td)
159 {
160 	struct smb_softc *sc = IIC_SOFTC(minor(dev));
161 
162 	if (sc == NULL)
163 		return (ENXIO);
164 
165 	if (sc->sc_count == 0)
166 		/* This is not supposed to happen. */
167 		return (0);
168 
169 	sc->sc_count--;
170 
171 	return (0);
172 }
173 
174 static int
175 smbioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td)
176 {
177 	char buf[SMB_MAXBLOCKSIZE];
178 	device_t parent;
179 	struct smbcmd *s = (struct smbcmd *)data;
180 	struct smb_softc *sc = IIC_SOFTC(minor(dev));
181 	device_t smbdev = IIC_DEVICE(minor(dev));
182 	int error;
183 	short w;
184 	u_char count;
185 	char c;
186 
187 	if (sc == NULL)
188 		return (ENXIO);
189 	if (s == NULL)
190 		return (EINVAL);
191 
192 	parent = device_get_parent(smbdev);
193 
194 	/* Allocate the bus. */
195 	if ((error = smbus_request_bus(parent, smbdev,
196 			(flags & O_NONBLOCK) ? SMB_DONTWAIT : (SMB_WAIT | SMB_INTR))))
197 		return (error);
198 
199 	switch (cmd) {
200 	case SMB_QUICK_WRITE:
201 		error = smbus_error(smbus_quick(parent, s->slave, SMB_QWRITE));
202 		break;
203 
204 	case SMB_QUICK_READ:
205 		error = smbus_error(smbus_quick(parent, s->slave, SMB_QREAD));
206 		break;
207 
208 	case SMB_SENDB:
209 		error = smbus_error(smbus_sendb(parent, s->slave, s->cmd));
210 		break;
211 
212 	case SMB_RECVB:
213 		error = smbus_error(smbus_recvb(parent, s->slave, &s->cmd));
214 		break;
215 
216 	case SMB_WRITEB:
217 		error = smbus_error(smbus_writeb(parent, s->slave, s->cmd,
218 						s->data.byte));
219 		break;
220 
221 	case SMB_WRITEW:
222 		error = smbus_error(smbus_writew(parent, s->slave,
223 						s->cmd, s->data.word));
224 		break;
225 
226 	case SMB_READB:
227 		if (s->data.byte_ptr) {
228 			error = smbus_error(smbus_readb(parent, s->slave,
229 						s->cmd, &c));
230 			if (error)
231 				break;
232 			error = copyout(&c, s->data.byte_ptr,
233 					sizeof(*(s->data.byte_ptr)));
234 		}
235 		break;
236 
237 	case SMB_READW:
238 		if (s->data.word_ptr) {
239 			error = smbus_error(smbus_readw(parent, s->slave,
240 						s->cmd, &w));
241 			if (error == 0) {
242 				error = copyout(&w, s->data.word_ptr,
243 						sizeof(*(s->data.word_ptr)));
244 			}
245 		}
246 		break;
247 
248 	case SMB_PCALL:
249 		if (s->data.process.rdata) {
250 
251 			error = smbus_error(smbus_pcall(parent, s->slave, s->cmd,
252 				s->data.process.sdata, &w));
253 			if (error)
254 				break;
255 			error = copyout(&w, s->data.process.rdata,
256 					sizeof(*(s->data.process.rdata)));
257 		}
258 
259 		break;
260 
261 	case SMB_BWRITE:
262 		if (s->count && s->data.byte_ptr) {
263 			if (s->count > SMB_MAXBLOCKSIZE)
264 				s->count = SMB_MAXBLOCKSIZE;
265 			error = copyin(s->data.byte_ptr, buf, s->count);
266 			if (error)
267 				break;
268 			error = smbus_error(smbus_bwrite(parent, s->slave,
269 						s->cmd, s->count, buf));
270 		}
271 		break;
272 
273 	case SMB_OLD_BREAD:
274 	case SMB_BREAD:
275 		if (s->count && s->data.byte_ptr) {
276 			count = min(s->count, SMB_MAXBLOCKSIZE);
277 			error = smbus_error(smbus_bread(parent, s->slave,
278 						s->cmd, &count, buf));
279 			if (error)
280 				break;
281 			error = copyout(buf, s->data.byte_ptr,
282 			    min(count, s->count));
283 			s->count = count;
284 		}
285 		break;
286 
287 	default:
288 		error = ENOTTY;
289 	}
290 
291 	smbus_release_bus(parent, smbdev);
292 
293 	return (error);
294 }
295 
296 DRIVER_MODULE(smb, smbus, smb_driver, smb_devclass, 0, 0);
297 MODULE_DEPEND(smb, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER);
298 MODULE_VERSION(smb, 1);
299