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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29
30 /*
31 * I2C bus IP driver
32 */
33
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/mbuf.h>
37 #include <sys/socket.h>
38 #include <sys/filio.h>
39 #include <sys/sockio.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/module.h>
43 #include <sys/mutex.h>
44 #include <sys/bus.h>
45 #include <sys/time.h>
46 #include <sys/malloc.h>
47
48 #include <net/if.h>
49 #include <net/if_types.h>
50 #include <net/netisr.h>
51
52 #include <net/route.h>
53 #include <netinet/in.h>
54 #include <netinet/in_systm.h>
55 #include <netinet/in_var.h>
56 #include <netinet/ip.h>
57 #include <netinet/if_ether.h>
58
59 #include <net/bpf.h>
60
61 #include <dev/iicbus/iiconf.h>
62 #include <dev/iicbus/iicbus.h>
63
64 #include "iicbus_if.h"
65
66 #define PCF_MASTER_ADDRESS 0xaa
67
68 #define ICHDRLEN sizeof(u_int32_t)
69 #define ICMTU 1500 /* default mtu */
70
71 struct ic_softc {
72 struct ifnet *ic_ifp;
73 device_t ic_dev;
74
75 u_char ic_addr; /* peer I2C address */
76
77 int ic_flags;
78
79 char *ic_obuf;
80 char *ic_ifbuf;
81 char *ic_cp;
82
83 int ic_xfercnt;
84
85 int ic_iferrs;
86
87 struct mtx ic_lock;
88 };
89
90 #define IC_SENDING 0x0001
91 #define IC_OBUF_BUSY 0x0002
92 #define IC_IFBUF_BUSY 0x0004
93 #define IC_BUFFERS_BUSY (IC_OBUF_BUSY | IC_IFBUF_BUSY)
94 #define IC_BUFFER_WAITER 0x0004
95
96 static devclass_t ic_devclass;
97
98 static int icprobe(device_t);
99 static int icattach(device_t);
100
101 static int icioctl(struct ifnet *, u_long, caddr_t);
102 static int icoutput(struct ifnet *, struct mbuf *, const struct sockaddr *,
103 struct route *);
104
105 static int icintr(device_t, int, char *);
106
107 static device_method_t ic_methods[] = {
108 /* device interface */
109 DEVMETHOD(device_probe, icprobe),
110 DEVMETHOD(device_attach, icattach),
111
112 /* iicbus interface */
113 DEVMETHOD(iicbus_intr, icintr),
114
115 { 0, 0 }
116 };
117
118 static driver_t ic_driver = {
119 "ic",
120 ic_methods,
121 sizeof(struct ic_softc),
122 };
123
124 static void
ic_alloc_buffers(struct ic_softc * sc,int mtu)125 ic_alloc_buffers(struct ic_softc *sc, int mtu)
126 {
127 char *obuf, *ifbuf;
128
129 obuf = malloc(mtu + ICHDRLEN, M_DEVBUF, M_WAITOK);
130 ifbuf = malloc(mtu + ICHDRLEN, M_DEVBUF, M_WAITOK);
131
132 mtx_lock(&sc->ic_lock);
133 while (sc->ic_flags & IC_BUFFERS_BUSY) {
134 sc->ic_flags |= IC_BUFFER_WAITER;
135 mtx_sleep(sc, &sc->ic_lock, 0, "icalloc", 0);
136 sc->ic_flags &= ~IC_BUFFER_WAITER;
137 }
138
139 free(sc->ic_obuf, M_DEVBUF);
140 free(sc->ic_ifbuf, M_DEVBUF);
141 sc->ic_obuf = obuf;
142 sc->ic_ifbuf = ifbuf;
143 sc->ic_ifp->if_mtu = mtu;
144 mtx_unlock(&sc->ic_lock);
145 }
146
147 /*
148 * icprobe()
149 */
150 static int
icprobe(device_t dev)151 icprobe(device_t dev)
152 {
153 return (BUS_PROBE_NOWILDCARD);
154 }
155
156 /*
157 * icattach()
158 */
159 static int
icattach(device_t dev)160 icattach(device_t dev)
161 {
162 struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
163 struct ifnet *ifp;
164
165 ifp = sc->ic_ifp = if_alloc(IFT_PARA);
166 if (ifp == NULL)
167 return (ENOSPC);
168
169 mtx_init(&sc->ic_lock, device_get_nameunit(dev), MTX_NETWORK_LOCK,
170 MTX_DEF);
171 sc->ic_addr = PCF_MASTER_ADDRESS; /* XXX only PCF masters */
172 sc->ic_dev = dev;
173
174 ifp->if_softc = sc;
175 if_initname(ifp, device_get_name(dev), device_get_unit(dev));
176 ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
177 ifp->if_ioctl = icioctl;
178 ifp->if_output = icoutput;
179 ifp->if_hdrlen = 0;
180 ifp->if_addrlen = 0;
181 ifp->if_snd.ifq_maxlen = ifqmaxlen;
182
183 ic_alloc_buffers(sc, ICMTU);
184
185 if_attach(ifp);
186
187 bpfattach(ifp, DLT_NULL, ICHDRLEN);
188
189 return (0);
190 }
191
192 /*
193 * iciotcl()
194 */
195 static int
icioctl(struct ifnet * ifp,u_long cmd,caddr_t data)196 icioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
197 {
198 struct ic_softc *sc = ifp->if_softc;
199 device_t icdev = sc->ic_dev;
200 device_t parent = device_get_parent(icdev);
201 struct ifaddr *ifa = (struct ifaddr *)data;
202 struct ifreq *ifr = (struct ifreq *)data;
203 int error;
204
205 switch (cmd) {
206
207 case SIOCAIFADDR:
208 case SIOCSIFADDR:
209 if (ifa->ifa_addr->sa_family != AF_INET)
210 return (EAFNOSUPPORT);
211 mtx_lock(&sc->ic_lock);
212 ifp->if_flags |= IFF_UP;
213 goto locked;
214 case SIOCSIFFLAGS:
215 mtx_lock(&sc->ic_lock);
216 locked:
217 if ((!(ifp->if_flags & IFF_UP)) &&
218 (ifp->if_drv_flags & IFF_DRV_RUNNING)) {
219
220 /* XXX disable PCF */
221 ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
222 mtx_unlock(&sc->ic_lock);
223
224 /* IFF_UP is not set, try to release the bus anyway */
225 iicbus_release_bus(parent, icdev);
226 break;
227 }
228 if (((ifp->if_flags & IFF_UP)) &&
229 (!(ifp->if_drv_flags & IFF_DRV_RUNNING))) {
230 mtx_unlock(&sc->ic_lock);
231 if ((error = iicbus_request_bus(parent, icdev,
232 IIC_WAIT | IIC_INTR)))
233 return (error);
234 mtx_lock(&sc->ic_lock);
235 iicbus_reset(parent, IIC_FASTEST, 0, NULL);
236 ifp->if_drv_flags |= IFF_DRV_RUNNING;
237 }
238 mtx_unlock(&sc->ic_lock);
239 break;
240
241 case SIOCSIFMTU:
242 ic_alloc_buffers(sc, ifr->ifr_mtu);
243 break;
244
245 case SIOCGIFMTU:
246 mtx_lock(&sc->ic_lock);
247 ifr->ifr_mtu = sc->ic_ifp->if_mtu;
248 mtx_unlock(&sc->ic_lock);
249 break;
250
251 case SIOCADDMULTI:
252 case SIOCDELMULTI:
253 if (ifr == 0)
254 return (EAFNOSUPPORT); /* XXX */
255 switch (ifr->ifr_addr.sa_family) {
256 case AF_INET:
257 break;
258 default:
259 return (EAFNOSUPPORT);
260 }
261 break;
262 default:
263 return (EINVAL);
264 }
265 return (0);
266 }
267
268 /*
269 * icintr()
270 */
271 static int
icintr(device_t dev,int event,char * ptr)272 icintr(device_t dev, int event, char *ptr)
273 {
274 struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
275 struct mbuf *top;
276 int len;
277
278 mtx_lock(&sc->ic_lock);
279
280 switch (event) {
281
282 case INTR_GENERAL:
283 case INTR_START:
284 sc->ic_cp = sc->ic_ifbuf;
285 sc->ic_xfercnt = 0;
286 sc->ic_flags |= IC_IFBUF_BUSY;
287 break;
288
289 case INTR_STOP:
290
291 /* if any error occured during transfert,
292 * drop the packet */
293 sc->ic_flags &= ~IC_IFBUF_BUSY;
294 if ((sc->ic_flags & (IC_BUFFERS_BUSY | IC_BUFFER_WAITER)) ==
295 IC_BUFFER_WAITER)
296 wakeup(&sc);
297 if (sc->ic_iferrs)
298 goto err;
299 if ((len = sc->ic_xfercnt) == 0)
300 break; /* ignore */
301 if (len <= ICHDRLEN)
302 goto err;
303 len -= ICHDRLEN;
304 sc->ic_ifp->if_ipackets++;
305 sc->ic_ifp->if_ibytes += len;
306 BPF_TAP(sc->ic_ifp, sc->ic_ifbuf, len + ICHDRLEN);
307 top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, sc->ic_ifp, 0);
308 if (top) {
309 mtx_unlock(&sc->ic_lock);
310 M_SETFIB(top, sc->ic_ifp->if_fib);
311 netisr_dispatch(NETISR_IP, top);
312 mtx_lock(&sc->ic_lock);
313 }
314 break;
315 err:
316 if_printf(sc->ic_ifp, "errors (%d)!\n", sc->ic_iferrs);
317 sc->ic_iferrs = 0; /* reset error count */
318 sc->ic_ifp->if_ierrors++;
319 break;
320
321 case INTR_RECEIVE:
322 if (sc->ic_xfercnt >= sc->ic_ifp->if_mtu + ICHDRLEN) {
323 sc->ic_iferrs++;
324 } else {
325 *sc->ic_cp++ = *ptr;
326 sc->ic_xfercnt++;
327 }
328 break;
329
330 case INTR_NOACK: /* xfer terminated by master */
331 break;
332
333 case INTR_TRANSMIT:
334 *ptr = 0xff; /* XXX */
335 break;
336
337 case INTR_ERROR:
338 sc->ic_iferrs++;
339 break;
340
341 default:
342 panic("%s: unknown event (%d)!", __func__, event);
343 }
344
345 mtx_unlock(&sc->ic_lock);
346 return (0);
347 }
348
349 /*
350 * icoutput()
351 */
352 static int
icoutput(struct ifnet * ifp,struct mbuf * m,const struct sockaddr * dst,struct route * ro)353 icoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
354 struct route *ro)
355 {
356 struct ic_softc *sc = ifp->if_softc;
357 device_t icdev = sc->ic_dev;
358 device_t parent = device_get_parent(icdev);
359 int len, sent;
360 struct mbuf *mm;
361 u_char *cp;
362 u_int32_t hdr;
363
364 /* BPF writes need to be handled specially. */
365 if (dst->sa_family == AF_UNSPEC)
366 bcopy(dst->sa_data, &hdr, sizeof(hdr));
367 else
368 hdr = dst->sa_family;
369
370 mtx_lock(&sc->ic_lock);
371 ifp->if_drv_flags |= IFF_DRV_RUNNING;
372
373 /* already sending? */
374 if (sc->ic_flags & IC_SENDING) {
375 ifp->if_oerrors++;
376 goto error;
377 }
378
379 /* insert header */
380 bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
381
382 cp = sc->ic_obuf + ICHDRLEN;
383 len = 0;
384 mm = m;
385 do {
386 if (len + mm->m_len > sc->ic_ifp->if_mtu) {
387 /* packet too large */
388 ifp->if_oerrors++;
389 goto error;
390 }
391
392 bcopy(mtod(mm,char *), cp, mm->m_len);
393 cp += mm->m_len;
394 len += mm->m_len;
395
396 } while ((mm = mm->m_next));
397
398 BPF_MTAP2(ifp, &hdr, sizeof(hdr), m);
399
400 sc->ic_flags |= (IC_SENDING | IC_OBUF_BUSY);
401
402 m_freem(m);
403 mtx_unlock(&sc->ic_lock);
404
405 /* send the packet */
406 if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
407 len + ICHDRLEN, &sent))
408
409 ifp->if_oerrors++;
410 else {
411 ifp->if_opackets++;
412 ifp->if_obytes += len;
413 }
414
415 mtx_lock(&sc->ic_lock);
416 sc->ic_flags &= ~(IC_SENDING | IC_OBUF_BUSY);
417 if ((sc->ic_flags & (IC_BUFFERS_BUSY | IC_BUFFER_WAITER)) ==
418 IC_BUFFER_WAITER)
419 wakeup(&sc);
420 mtx_unlock(&sc->ic_lock);
421
422 return (0);
423
424 error:
425 m_freem(m);
426 mtx_unlock(&sc->ic_lock);
427
428 return(0);
429 }
430
431 DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
432 MODULE_DEPEND(ic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
433 MODULE_VERSION(ic, 1);
434