xref: /freebsd/sys/dev/iicbus/if_ic.c (revision 2ad872c5794e4c26fdf6ed219ad3f09ca0d5304a)
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 1.2 1998/10/31 11:31:07 nsouch 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, 0, NULL);
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 
294 	s = splhigh();
295 
296 	switch (event) {
297 
298 	case INTR_GENERAL:
299 	case INTR_START:
300 		sc->ic_cp = sc->ic_ifbuf;
301 		sc->ic_xfercnt = 0;
302 		break;
303 
304 	case INTR_STOP:
305 
306 	  /* if any error occured during transfert,
307 	   * drop the packet */
308 	  if (sc->ic_iferrs)
309 	    goto err;
310 
311 	  if ((len = sc->ic_xfercnt) == 0)
312 		break;					/* ignore */
313 
314 	  if (len <= ICHDRLEN)
315 	    goto err;
316 
317 	  if (IF_QFULL(&ipintrq)) {
318 	    IF_DROP(&ipintrq);
319 	    break;
320 	  }
321 
322 	  len -= ICHDRLEN;
323 	  sc->ic_if.if_ipackets ++;
324 	  sc->ic_if.if_ibytes += len;
325 
326 #if NBPFILTER > 0
327 	if (sc->ic_if.if_bpf)
328 		bpf_tap(&sc->ic_if, sc->ic_ifbuf, len + ICHDRLEN);
329 #endif
330 
331 	  top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, &sc->ic_if, 0);
332 
333 	  if (top) {
334 	    IF_ENQUEUE(&ipintrq, top);
335 	    schednetisr(NETISR_IP);
336 	  }
337 	  break;
338 
339 	err:
340 	  printf("ic%d: errors (%d)!\n", unit, sc->ic_iferrs);
341 
342 	  sc->ic_iferrs = 0;			/* reset error count */
343 	  sc->ic_if.if_ierrors ++;
344 
345 	  break;
346 
347 	case INTR_RECEIVE:
348 		if (sc->ic_xfercnt >= sc->ic_if.if_mtu+ICHDRLEN) {
349 			sc->ic_iferrs ++;
350 
351 		} else {
352 			*sc->ic_cp++ = *ptr;
353 			sc->ic_xfercnt ++;
354 		}
355 		break;
356 
357 	case INTR_NOACK:			/* xfer terminated by master */
358 		break;
359 
360 	case INTR_TRANSMIT:
361 		*ptr = 0xff;					/* XXX */
362 	  	break;
363 
364 	case INTR_ERROR:
365 		sc->ic_iferrs ++;
366 		break;
367 
368 	default:
369 		panic("%s: unknown event (%d)!", __FUNCTION__, event);
370 	}
371 
372 	splx(s);
373 	return;
374 }
375 
376 /*
377  * icoutput()
378  */
379 static int
380 icoutput(struct ifnet *ifp, struct mbuf *m,
381 	struct sockaddr *dst, struct rtentry *rt)
382 {
383 	device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
384 	device_t parent = device_get_parent(icdev);
385 	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
386 
387 	int s, len, sent;
388 	struct mbuf *mm;
389 	u_char *cp;
390 	u_int hdr = dst->sa_family;
391 
392 	ifp->if_flags |= IFF_RUNNING;
393 
394 	s = splhigh();
395 
396 	/* already sending? */
397 	if (sc->ic_sending) {
398 		ifp->if_oerrors ++;
399 		goto error;
400 	}
401 
402 	/* insert header */
403 	bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
404 
405 	cp = sc->ic_obuf + ICHDRLEN;
406 	len = 0;
407 	mm = m;
408 	do {
409 		if (len + mm->m_len > sc->ic_if.if_mtu) {
410 			/* packet to large */
411 			ifp->if_oerrors ++;
412 			goto error;
413 		}
414 
415 		bcopy(mtod(mm,char *), cp, mm->m_len);
416 		cp += mm->m_len;
417 		len += mm->m_len;
418 
419 	} while ((mm = mm->m_next));
420 
421 #if NBPFILTER > 0
422 	if (ifp->if_bpf) {
423 		struct mbuf m0, *n = m;
424 
425 		/*
426 		 * We need to prepend the address family as
427 		 * a four byte field.  Cons up a dummy header
428 		 * to pacify bpf.  This is safe because bpf
429 		 * will only read from the mbuf (i.e., it won't
430 		 * try to free it or keep a pointer a to it).
431 		 */
432 		m0.m_next = m;
433 		m0.m_len = sizeof(u_int);
434 		m0.m_data = (char *)&hdr;
435 		n = &m0;
436 
437 		bpf_mtap(ifp, n);
438 	}
439 #endif
440 
441 	sc->ic_sending = 1;
442 
443 	m_freem(m);
444 	splx(s);
445 
446 	/* send the packet */
447 	if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
448 				len + ICHDRLEN, &sent))
449 
450 		ifp->if_oerrors ++;
451 	else {
452 		ifp->if_opackets ++;
453 		ifp->if_obytes += len;
454 	}
455 
456 	sc->ic_sending = 0;
457 
458 	return (0);
459 
460 error:
461 	m_freem(m);
462 	splx(s);
463 
464 	return(0);
465 }
466 
467 DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
468