xref: /freebsd/sys/dev/iicbus/if_ic.c (revision 6e8394b8baa7d5d9153ab90de6824bcd19b3b4e1)
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 1.3 1998/12/07 21:58:16 archie 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 	sizeof(struct ic_softc),
118 };
119 
120 /*
121  * icprobe()
122  */
123 static int
124 icprobe(device_t dev)
125 {
126 	return (0);
127 }
128 
129 /*
130  * icattach()
131  */
132 static int
133 icattach(device_t dev)
134 {
135 	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
136 	struct ifnet *ifp = &sc->ic_if;
137 
138 	sc->ic_addr = iicbus_get_addr(dev);
139 
140 	ifp->if_softc = sc;
141 	ifp->if_name = "ic";
142 	ifp->if_unit = device_get_unit(dev);
143 	ifp->if_mtu = ICMTU;
144 	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
145 	ifp->if_ioctl = icioctl;
146 	ifp->if_output = icoutput;
147 	ifp->if_type = IFT_PARA;
148 	ifp->if_hdrlen = 0;
149 	ifp->if_addrlen = 0;
150 	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
151 
152 	if_attach(ifp);
153 
154 #if NBPFILTER > 0
155 	bpfattach(ifp, DLT_NULL, ICHDRLEN);
156 #endif
157 
158 	return (0);
159 }
160 
161 /*
162  * iciotcl()
163  */
164 static int
165 icioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
166 {
167     device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
168     device_t parent = device_get_parent(icdev);
169     struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
170 
171     struct ifaddr *ifa = (struct ifaddr *)data;
172     struct ifreq *ifr = (struct ifreq *)data;
173 
174     u_char *iptr, *optr;
175     int error;
176 
177     switch (cmd) {
178 
179     case SIOCSIFDSTADDR:
180     case SIOCAIFADDR:
181     case SIOCSIFADDR:
182 	if (ifa->ifa_addr->sa_family != AF_INET)
183 	    return EAFNOSUPPORT;
184 	ifp->if_flags |= IFF_UP;
185 	/* FALLTHROUGH */
186     case SIOCSIFFLAGS:
187 	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
188 
189 	    /* XXX disable PCF */
190 	    ifp->if_flags &= ~IFF_RUNNING;
191 
192 	    /* IFF_UP is not set, try to release the bus anyway */
193 	    iicbus_release_bus(parent, icdev);
194 	    break;
195 	}
196 	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
197 
198 	    if ((error = iicbus_request_bus(parent, icdev, IIC_WAIT|IIC_INTR)))
199 		return (error);
200 
201 	    sc->ic_obuf = malloc(sc->ic_if.if_mtu + ICHDRLEN,
202 				  M_DEVBUF, M_WAITOK);
203 	    if (!sc->ic_obuf) {
204 		iicbus_release_bus(parent, icdev);
205 		return ENOBUFS;
206 	    }
207 
208 	    sc->ic_ifbuf = malloc(sc->ic_if.if_mtu + ICHDRLEN,
209 				  M_DEVBUF, M_WAITOK);
210 	    if (!sc->ic_ifbuf) {
211 		iicbus_release_bus(parent, icdev);
212 		return ENOBUFS;
213 	    }
214 
215 	    iicbus_reset(parent, IIC_FASTEST, 0, NULL);
216 
217 	    ifp->if_flags |= IFF_RUNNING;
218 	}
219 	break;
220 
221     case SIOCSIFMTU:
222 	/* save previous buffers */
223 	iptr = sc->ic_ifbuf;
224 	optr = sc->ic_obuf;
225 
226 	/* allocate input buffer */
227 	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
228 	if (!sc->ic_ifbuf) {
229 
230 	    sc->ic_ifbuf = iptr;
231 	    sc->ic_obuf = optr;
232 
233 	    return ENOBUFS;
234 	}
235 
236 	/* allocate output buffer */
237 	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
238 	if (!sc->ic_obuf) {
239 
240 	    free(sc->ic_ifbuf,M_DEVBUF);
241 
242 	    sc->ic_ifbuf = iptr;
243 	    sc->ic_obuf = optr;
244 
245 	    return ENOBUFS;
246 	}
247 
248 	if (iptr)
249 	    free(iptr,M_DEVBUF);
250 
251 	if (optr)
252 	    free(optr,M_DEVBUF);
253 
254 	sc->ic_if.if_mtu = ifr->ifr_mtu;
255 	break;
256 
257     case SIOCGIFMTU:
258 	ifr->ifr_mtu = sc->ic_if.if_mtu;
259 	break;
260 
261     case SIOCADDMULTI:
262     case SIOCDELMULTI:
263 	if (ifr == 0) {
264 	    return EAFNOSUPPORT;		/* XXX */
265 	}
266 	switch (ifr->ifr_addr.sa_family) {
267 
268 	case AF_INET:
269 	    break;
270 
271 	default:
272 	    return EAFNOSUPPORT;
273 	}
274 	break;
275 
276     default:
277 	return EINVAL;
278     }
279     return 0;
280 }
281 
282 /*
283  * icintr()
284  */
285 static void
286 icintr (device_t dev, int event, char *ptr)
287 {
288 	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
289 	int unit = device_get_unit(dev);
290 	int s, len;
291 	struct mbuf *top;
292 
293 	s = splhigh();
294 
295 	switch (event) {
296 
297 	case INTR_GENERAL:
298 	case INTR_START:
299 		sc->ic_cp = sc->ic_ifbuf;
300 		sc->ic_xfercnt = 0;
301 		break;
302 
303 	case INTR_STOP:
304 
305 	  /* if any error occured during transfert,
306 	   * drop the packet */
307 	  if (sc->ic_iferrs)
308 	    goto err;
309 
310 	  if ((len = sc->ic_xfercnt) == 0)
311 		break;					/* ignore */
312 
313 	  if (len <= ICHDRLEN)
314 	    goto err;
315 
316 	  if (IF_QFULL(&ipintrq)) {
317 	    IF_DROP(&ipintrq);
318 	    break;
319 	  }
320 
321 	  len -= ICHDRLEN;
322 	  sc->ic_if.if_ipackets ++;
323 	  sc->ic_if.if_ibytes += len;
324 
325 #if NBPFILTER > 0
326 	if (sc->ic_if.if_bpf)
327 		bpf_tap(&sc->ic_if, sc->ic_ifbuf, len + ICHDRLEN);
328 #endif
329 
330 	  top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, &sc->ic_if, 0);
331 
332 	  if (top) {
333 	    IF_ENQUEUE(&ipintrq, top);
334 	    schednetisr(NETISR_IP);
335 	  }
336 	  break;
337 
338 	err:
339 	  printf("ic%d: errors (%d)!\n", unit, sc->ic_iferrs);
340 
341 	  sc->ic_iferrs = 0;			/* reset error count */
342 	  sc->ic_if.if_ierrors ++;
343 
344 	  break;
345 
346 	case INTR_RECEIVE:
347 		if (sc->ic_xfercnt >= sc->ic_if.if_mtu+ICHDRLEN) {
348 			sc->ic_iferrs ++;
349 
350 		} else {
351 			*sc->ic_cp++ = *ptr;
352 			sc->ic_xfercnt ++;
353 		}
354 		break;
355 
356 	case INTR_NOACK:			/* xfer terminated by master */
357 		break;
358 
359 	case INTR_TRANSMIT:
360 		*ptr = 0xff;					/* XXX */
361 	  	break;
362 
363 	case INTR_ERROR:
364 		sc->ic_iferrs ++;
365 		break;
366 
367 	default:
368 		panic("%s: unknown event (%d)!", __FUNCTION__, event);
369 	}
370 
371 	splx(s);
372 	return;
373 }
374 
375 /*
376  * icoutput()
377  */
378 static int
379 icoutput(struct ifnet *ifp, struct mbuf *m,
380 	struct sockaddr *dst, struct rtentry *rt)
381 {
382 	device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
383 	device_t parent = device_get_parent(icdev);
384 	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
385 
386 	int s, len, sent;
387 	struct mbuf *mm;
388 	u_char *cp;
389 	u_int hdr = dst->sa_family;
390 
391 	ifp->if_flags |= IFF_RUNNING;
392 
393 	s = splhigh();
394 
395 	/* already sending? */
396 	if (sc->ic_sending) {
397 		ifp->if_oerrors ++;
398 		goto error;
399 	}
400 
401 	/* insert header */
402 	bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
403 
404 	cp = sc->ic_obuf + ICHDRLEN;
405 	len = 0;
406 	mm = m;
407 	do {
408 		if (len + mm->m_len > sc->ic_if.if_mtu) {
409 			/* packet to large */
410 			ifp->if_oerrors ++;
411 			goto error;
412 		}
413 
414 		bcopy(mtod(mm,char *), cp, mm->m_len);
415 		cp += mm->m_len;
416 		len += mm->m_len;
417 
418 	} while ((mm = mm->m_next));
419 
420 #if NBPFILTER > 0
421 	if (ifp->if_bpf) {
422 		struct mbuf m0, *n = m;
423 
424 		/*
425 		 * We need to prepend the address family as
426 		 * a four byte field.  Cons up a dummy header
427 		 * to pacify bpf.  This is safe because bpf
428 		 * will only read from the mbuf (i.e., it won't
429 		 * try to free it or keep a pointer a to it).
430 		 */
431 		m0.m_next = m;
432 		m0.m_len = sizeof(u_int);
433 		m0.m_data = (char *)&hdr;
434 		n = &m0;
435 
436 		bpf_mtap(ifp, n);
437 	}
438 #endif
439 
440 	sc->ic_sending = 1;
441 
442 	m_freem(m);
443 	splx(s);
444 
445 	/* send the packet */
446 	if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
447 				len + ICHDRLEN, &sent))
448 
449 		ifp->if_oerrors ++;
450 	else {
451 		ifp->if_opackets ++;
452 		ifp->if_obytes += len;
453 	}
454 
455 	sc->ic_sending = 0;
456 
457 	return (0);
458 
459 error:
460 	m_freem(m);
461 	splx(s);
462 
463 	return(0);
464 }
465 
466 DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
467