xref: /freebsd/sys/dev/iicbus/if_ic.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
1 /*-
2  * Copyright (c) 1998 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  *	$Id: if_ic.c,v 1.1.1.11 1998/08/13 17:10:42 son Exp $
27  */
28 
29 /*
30  * I2C bus IP driver
31  */
32 
33 #ifdef KERNEL
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/proc.h>
37 #include <sys/mbuf.h>
38 #include <sys/socket.h>
39 #include <sys/filio.h>
40 #include <sys/sockio.h>
41 #include <sys/kernel.h>
42 #include <sys/module.h>
43 #include <sys/bus.h>
44 #include <sys/time.h>
45 #include <sys/malloc.h>
46 
47 #include <net/if.h>
48 #include <net/if_types.h>
49 #include <net/netisr.h>
50 
51 #endif /* KERNEL */
52 #include <sys/mbuf.h>
53 #include <sys/socket.h>
54 #include <net/netisr.h>
55 #include <net/route.h>
56 #include <netinet/in.h>
57 #include <netinet/in_systm.h>
58 #include <netinet/in_var.h>
59 #include <netinet/ip.h>
60 #include <netinet/if_ether.h>
61 
62 #include "bpfilter.h"
63 
64 #if NBPFILTER > 0
65 #include <net/bpf.h>
66 #endif
67 
68 #include <dev/iicbus/iiconf.h>
69 #include <dev/iicbus/iicbus.h>
70 
71 #include "iicbus_if.h"
72 
73 #define ICHDRLEN	sizeof(u_int)
74 #define ICMTU		1500		/* default mtu */
75 
76 struct ic_softc {
77 	struct ifnet ic_if;
78 
79 	u_char ic_addr;			/* peer I2C address */
80 
81 	int ic_sending;
82 
83 	char *ic_obuf;
84 	char *ic_ifbuf;
85 	char *ic_cp;
86 
87 	int ic_xfercnt;
88 
89 	int ic_iferrs;
90 };
91 
92 static devclass_t ic_devclass;
93 
94 static int icprobe(device_t);
95 static int icattach(device_t);
96 
97 static int icioctl(struct ifnet *, u_long, caddr_t);
98 static int icoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
99 		struct rtentry *);
100 
101 static void icintr(device_t, int, char *);
102 
103 static device_method_t ic_methods[] = {
104 	/* device interface */
105 	DEVMETHOD(device_probe,		icprobe),
106 	DEVMETHOD(device_attach,	icattach),
107 
108 	/* iicbus interface */
109 	DEVMETHOD(iicbus_intr,		icintr),
110 
111 	{ 0, 0 }
112 };
113 
114 static driver_t ic_driver = {
115 	"ic",
116 	ic_methods,
117 	DRIVER_TYPE_MISC,
118 	sizeof(struct ic_softc),
119 };
120 
121 /*
122  * icprobe()
123  */
124 static int
125 icprobe(device_t dev)
126 {
127 	return (0);
128 }
129 
130 /*
131  * icattach()
132  */
133 static int
134 icattach(device_t dev)
135 {
136 	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
137 	struct ifnet *ifp = &sc->ic_if;
138 
139 	sc->ic_addr = iicbus_get_addr(dev);
140 
141 	ifp->if_softc = sc;
142 	ifp->if_name = "ic";
143 	ifp->if_unit = device_get_unit(dev);
144 	ifp->if_mtu = ICMTU;
145 	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
146 	ifp->if_ioctl = icioctl;
147 	ifp->if_output = icoutput;
148 	ifp->if_type = IFT_PARA;
149 	ifp->if_hdrlen = 0;
150 	ifp->if_addrlen = 0;
151 	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
152 
153 	if_attach(ifp);
154 
155 #if NBPFILTER > 0
156 	bpfattach(ifp, DLT_NULL, ICHDRLEN);
157 #endif
158 
159 	return (0);
160 }
161 
162 /*
163  * iciotcl()
164  */
165 static int
166 icioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
167 {
168     device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
169     device_t parent = device_get_parent(icdev);
170     struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
171 
172     struct ifaddr *ifa = (struct ifaddr *)data;
173     struct ifreq *ifr = (struct ifreq *)data;
174 
175     u_char *iptr, *optr;
176     int error;
177 
178     switch (cmd) {
179 
180     case SIOCSIFDSTADDR:
181     case SIOCAIFADDR:
182     case SIOCSIFADDR:
183 	if (ifa->ifa_addr->sa_family != AF_INET)
184 	    return EAFNOSUPPORT;
185 	ifp->if_flags |= IFF_UP;
186 	/* FALLTHROUGH */
187     case SIOCSIFFLAGS:
188 	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
189 
190 	    /* XXX disable PCF */
191 	    ifp->if_flags &= ~IFF_RUNNING;
192 
193 	    /* IFF_UP is not set, try to release the bus anyway */
194 	    iicbus_release_bus(parent, icdev);
195 	    break;
196 	}
197 	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
198 
199 	    if ((error = iicbus_request_bus(parent, icdev, IIC_WAIT|IIC_INTR)))
200 		return (error);
201 
202 	    sc->ic_obuf = malloc(sc->ic_if.if_mtu + ICHDRLEN,
203 				  M_DEVBUF, M_WAITOK);
204 	    if (!sc->ic_obuf) {
205 		iicbus_release_bus(parent, icdev);
206 		return ENOBUFS;
207 	    }
208 
209 	    sc->ic_ifbuf = malloc(sc->ic_if.if_mtu + ICHDRLEN,
210 				  M_DEVBUF, M_WAITOK);
211 	    if (!sc->ic_ifbuf) {
212 		iicbus_release_bus(parent, icdev);
213 		return ENOBUFS;
214 	    }
215 
216 	    iicbus_reset(parent, IIC_FASTEST);
217 
218 	    ifp->if_flags |= IFF_RUNNING;
219 	}
220 	break;
221 
222     case SIOCSIFMTU:
223 	/* save previous buffers */
224 	iptr = sc->ic_ifbuf;
225 	optr = sc->ic_obuf;
226 
227 	/* allocate input buffer */
228 	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
229 	if (!sc->ic_ifbuf) {
230 
231 	    sc->ic_ifbuf = iptr;
232 	    sc->ic_obuf = optr;
233 
234 	    return ENOBUFS;
235 	}
236 
237 	/* allocate output buffer */
238 	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
239 	if (!sc->ic_obuf) {
240 
241 	    free(sc->ic_ifbuf,M_DEVBUF);
242 
243 	    sc->ic_ifbuf = iptr;
244 	    sc->ic_obuf = optr;
245 
246 	    return ENOBUFS;
247 	}
248 
249 	if (iptr)
250 	    free(iptr,M_DEVBUF);
251 
252 	if (optr)
253 	    free(optr,M_DEVBUF);
254 
255 	sc->ic_if.if_mtu = ifr->ifr_mtu;
256 	break;
257 
258     case SIOCGIFMTU:
259 	ifr->ifr_mtu = sc->ic_if.if_mtu;
260 	break;
261 
262     case SIOCADDMULTI:
263     case SIOCDELMULTI:
264 	if (ifr == 0) {
265 	    return EAFNOSUPPORT;		/* XXX */
266 	}
267 	switch (ifr->ifr_addr.sa_family) {
268 
269 	case AF_INET:
270 	    break;
271 
272 	default:
273 	    return EAFNOSUPPORT;
274 	}
275 	break;
276 
277     default:
278 	return EINVAL;
279     }
280     return 0;
281 }
282 
283 /*
284  * icintr()
285  */
286 static void
287 icintr (device_t dev, int event, char *ptr)
288 {
289 	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
290 	int unit = device_get_unit(dev);
291 	int s, len;
292 	struct mbuf *top;
293 	int i;
294 
295 	s = splhigh();
296 
297 	switch (event) {
298 
299 	case INTR_GENERAL:
300 	case INTR_START:
301 		sc->ic_cp = sc->ic_ifbuf;
302 		sc->ic_xfercnt = 0;
303 		break;
304 
305 	case INTR_STOP:
306 
307 	  /* if any error occured during transfert,
308 	   * drop the packet */
309 	  if (sc->ic_iferrs)
310 	    goto err;
311 
312 	  if ((len = sc->ic_xfercnt) == 0)
313 		break;					/* ignore */
314 
315 	  if (len <= ICHDRLEN)
316 	    goto err;
317 
318 	  if (IF_QFULL(&ipintrq)) {
319 	    IF_DROP(&ipintrq);
320 	    break;
321 	  }
322 
323 	  len -= ICHDRLEN;
324 	  sc->ic_if.if_ipackets ++;
325 	  sc->ic_if.if_ibytes += len;
326 
327 #if NBPFILTER > 0
328 	if (sc->ic_if.if_bpf)
329 		bpf_tap(&sc->ic_if, sc->ic_ifbuf, len + ICHDRLEN);
330 #endif
331 
332 	  top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, &sc->ic_if, 0);
333 
334 	  if (top) {
335 	    IF_ENQUEUE(&ipintrq, top);
336 	    schednetisr(NETISR_IP);
337 	  }
338 	  break;
339 
340 	err:
341 	  printf("ic%d: errors (%d)!\n", unit, sc->ic_iferrs);
342 
343 	  sc->ic_iferrs = 0;			/* reset error count */
344 	  sc->ic_if.if_ierrors ++;
345 
346 	  break;
347 
348 	case INTR_RECEIVE:
349 		if (sc->ic_xfercnt >= sc->ic_if.if_mtu+ICHDRLEN) {
350 			sc->ic_iferrs ++;
351 
352 		} else {
353 			*sc->ic_cp++ = *ptr;
354 			sc->ic_xfercnt ++;
355 		}
356 		break;
357 
358 	case INTR_NOACK:			/* xfer terminated by master */
359 		break;
360 
361 	case INTR_TRANSMIT:
362 		*ptr = 0xff;					/* XXX */
363 	  	break;
364 
365 	case INTR_ERROR:
366 		sc->ic_iferrs ++;
367 		break;
368 
369 	default:
370 		panic("%s: unknown event (%d)!", __FUNCTION__, event);
371 	}
372 
373 	splx(s);
374 	return;
375 }
376 
377 /*
378  * icoutput()
379  */
380 static int
381 icoutput(struct ifnet *ifp, struct mbuf *m,
382 	struct sockaddr *dst, struct rtentry *rt)
383 {
384 	device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
385 	device_t parent = device_get_parent(icdev);
386 	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
387 
388 	int s, len, sent;
389 	struct mbuf *mm;
390 	u_char *cp;
391 	u_int hdr = dst->sa_family;
392 
393 	ifp->if_flags |= IFF_RUNNING;
394 
395 	s = splhigh();
396 
397 	/* already sending? */
398 	if (sc->ic_sending) {
399 		ifp->if_oerrors ++;
400 		goto error;
401 	}
402 
403 	/* insert header */
404 	bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
405 
406 	cp = sc->ic_obuf + ICHDRLEN;
407 	len = 0;
408 	mm = m;
409 	do {
410 		if (len + mm->m_len > sc->ic_if.if_mtu) {
411 			/* packet to large */
412 			ifp->if_oerrors ++;
413 			goto error;
414 		}
415 
416 		bcopy(mtod(mm,char *), cp, mm->m_len);
417 		cp += mm->m_len;
418 		len += mm->m_len;
419 
420 	} while ((mm = mm->m_next));
421 
422 #if NBPFILTER > 0
423 	if (ifp->if_bpf) {
424 		struct mbuf m0, *n = m;
425 
426 		/*
427 		 * We need to prepend the address family as
428 		 * a four byte field.  Cons up a dummy header
429 		 * to pacify bpf.  This is safe because bpf
430 		 * will only read from the mbuf (i.e., it won't
431 		 * try to free it or keep a pointer a to it).
432 		 */
433 		m0.m_next = m;
434 		m0.m_len = sizeof(u_int);
435 		m0.m_data = (char *)&hdr;
436 		n = &m0;
437 
438 		bpf_mtap(ifp, n);
439 	}
440 #endif
441 
442 	sc->ic_sending = 1;
443 
444 	m_freem(m);
445 	splx(s);
446 
447 	/* send the packet */
448 	if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
449 				len + ICHDRLEN, &sent))
450 
451 		ifp->if_oerrors ++;
452 	else {
453 		ifp->if_opackets ++;
454 		ifp->if_obytes += len;
455 	}
456 
457 	sc->ic_sending = 0;
458 
459 	return (0);
460 
461 error:
462 	m_freem(m);
463 	splx(s);
464 
465 	return(0);
466 }
467 
468 DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
469