if_ic.c revision 106937 
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: head/sys/dev/iicbus/if_ic.c 106937 2002-11-14 23:54:55Z sam $
27 */
28
29/*
30 * I2C bus IP driver
31 */
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/mbuf.h>
36#include <sys/socket.h>
37#include <sys/filio.h>
38#include <sys/sockio.h>
39#include <sys/kernel.h>
40#include <sys/module.h>
41#include <sys/bus.h>
42#include <sys/time.h>
43#include <sys/malloc.h>
44
45#include <net/if.h>
46#include <net/if_types.h>
47#include <net/netisr.h>
48
49#include <sys/mbuf.h>
50#include <sys/socket.h>
51#include <net/netisr.h>
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_int)
69#define ICMTU		1500		/* default mtu */
70
71struct ic_softc {
72	struct ifnet ic_if;
73
74	u_char ic_addr;			/* peer I2C address */
75
76	int ic_sending;
77
78	char *ic_obuf;
79	char *ic_ifbuf;
80	char *ic_cp;
81
82	int ic_xfercnt;
83
84	int ic_iferrs;
85};
86
87static devclass_t ic_devclass;
88
89static int icprobe(device_t);
90static int icattach(device_t);
91
92static int icioctl(struct ifnet *, u_long, caddr_t);
93static int icoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
94		struct rtentry *);
95
96static void icintr(device_t, int, char *);
97
98static device_method_t ic_methods[] = {
99	/* device interface */
100	DEVMETHOD(device_probe,		icprobe),
101	DEVMETHOD(device_attach,	icattach),
102
103	/* iicbus interface */
104	DEVMETHOD(iicbus_intr,		icintr),
105
106	{ 0, 0 }
107};
108
109static driver_t ic_driver = {
110	"ic",
111	ic_methods,
112	sizeof(struct ic_softc),
113};
114
115/*
116 * icprobe()
117 */
118static int
119icprobe(device_t dev)
120{
121	return (0);
122}
123
124/*
125 * icattach()
126 */
127static int
128icattach(device_t dev)
129{
130	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
131	struct ifnet *ifp = &sc->ic_if;
132
133	sc->ic_addr = PCF_MASTER_ADDRESS;	/* XXX only PCF masters */
134
135	ifp->if_softc = sc;
136	ifp->if_name = "ic";
137	ifp->if_unit = device_get_unit(dev);
138	ifp->if_mtu = ICMTU;
139	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
140	ifp->if_ioctl = icioctl;
141	ifp->if_output = icoutput;
142	ifp->if_type = IFT_PARA;
143	ifp->if_hdrlen = 0;
144	ifp->if_addrlen = 0;
145	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
146
147	if_attach(ifp);
148
149	bpfattach(ifp, DLT_NULL, ICHDRLEN);
150
151	return (0);
152}
153
154/*
155 * iciotcl()
156 */
157static int
158icioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
159{
160    device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
161    device_t parent = device_get_parent(icdev);
162    struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
163
164    struct ifaddr *ifa = (struct ifaddr *)data;
165    struct ifreq *ifr = (struct ifreq *)data;
166
167    u_char *iptr, *optr;
168    int error;
169
170    switch (cmd) {
171
172    case SIOCSIFDSTADDR:
173    case SIOCAIFADDR:
174    case SIOCSIFADDR:
175	if (ifa->ifa_addr->sa_family != AF_INET)
176	    return EAFNOSUPPORT;
177	ifp->if_flags |= IFF_UP;
178	/* FALLTHROUGH */
179    case SIOCSIFFLAGS:
180	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
181
182	    /* XXX disable PCF */
183	    ifp->if_flags &= ~IFF_RUNNING;
184
185	    /* IFF_UP is not set, try to release the bus anyway */
186	    iicbus_release_bus(parent, icdev);
187	    break;
188	}
189	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
190
191	    if ((error = iicbus_request_bus(parent, icdev, IIC_WAIT|IIC_INTR)))
192		return (error);
193
194	    sc->ic_obuf = malloc(sc->ic_if.if_mtu + ICHDRLEN,
195				  M_DEVBUF, M_WAITOK);
196	    if (!sc->ic_obuf) {
197		iicbus_release_bus(parent, icdev);
198		return ENOBUFS;
199	    }
200
201	    sc->ic_ifbuf = malloc(sc->ic_if.if_mtu + ICHDRLEN,
202				  M_DEVBUF, M_WAITOK);
203	    if (!sc->ic_ifbuf) {
204		iicbus_release_bus(parent, icdev);
205		return ENOBUFS;
206	    }
207
208	    iicbus_reset(parent, IIC_FASTEST, 0, NULL);
209
210	    ifp->if_flags |= IFF_RUNNING;
211	}
212	break;
213
214    case SIOCSIFMTU:
215	/* save previous buffers */
216	iptr = sc->ic_ifbuf;
217	optr = sc->ic_obuf;
218
219	/* allocate input buffer */
220	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
221	if (!sc->ic_ifbuf) {
222
223	    sc->ic_ifbuf = iptr;
224	    sc->ic_obuf = optr;
225
226	    return ENOBUFS;
227	}
228
229	/* allocate output buffer */
230	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
231	if (!sc->ic_obuf) {
232
233	    free(sc->ic_ifbuf,M_DEVBUF);
234
235	    sc->ic_ifbuf = iptr;
236	    sc->ic_obuf = optr;
237
238	    return ENOBUFS;
239	}
240
241	if (iptr)
242	    free(iptr,M_DEVBUF);
243
244	if (optr)
245	    free(optr,M_DEVBUF);
246
247	sc->ic_if.if_mtu = ifr->ifr_mtu;
248	break;
249
250    case SIOCGIFMTU:
251	ifr->ifr_mtu = sc->ic_if.if_mtu;
252	break;
253
254    case SIOCADDMULTI:
255    case SIOCDELMULTI:
256	if (ifr == 0) {
257	    return EAFNOSUPPORT;		/* XXX */
258	}
259	switch (ifr->ifr_addr.sa_family) {
260
261	case AF_INET:
262	    break;
263
264	default:
265	    return EAFNOSUPPORT;
266	}
267	break;
268
269    default:
270	return EINVAL;
271    }
272    return 0;
273}
274
275/*
276 * icintr()
277 */
278static void
279icintr (device_t dev, int event, char *ptr)
280{
281	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
282	int unit = device_get_unit(dev);
283	int s, len;
284	struct mbuf *top;
285
286	s = splhigh();
287
288	switch (event) {
289
290	case INTR_GENERAL:
291	case INTR_START:
292		sc->ic_cp = sc->ic_ifbuf;
293		sc->ic_xfercnt = 0;
294		break;
295
296	case INTR_STOP:
297
298	  /* if any error occured during transfert,
299	   * drop the packet */
300	  if (sc->ic_iferrs)
301	    goto err;
302
303	  if ((len = sc->ic_xfercnt) == 0)
304		break;					/* ignore */
305
306	  if (len <= ICHDRLEN)
307	    goto err;
308
309	  len -= ICHDRLEN;
310	  sc->ic_if.if_ipackets ++;
311	  sc->ic_if.if_ibytes += len;
312
313	  BPF_TAP(&sc->ic_if, sc->ic_ifbuf, len + ICHDRLEN);
314
315	  top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, &sc->ic_if, 0);
316
317	  if (top) {
318	    if (IF_HANDOFF(&ipintrq, top, NULL))
319	      schednetisr(NETISR_IP);
320	  }
321	  break;
322
323	err:
324	  printf("ic%d: errors (%d)!\n", unit, sc->ic_iferrs);
325
326	  sc->ic_iferrs = 0;			/* reset error count */
327	  sc->ic_if.if_ierrors ++;
328
329	  break;
330
331	case INTR_RECEIVE:
332		if (sc->ic_xfercnt >= sc->ic_if.if_mtu+ICHDRLEN) {
333			sc->ic_iferrs ++;
334
335		} else {
336			*sc->ic_cp++ = *ptr;
337			sc->ic_xfercnt ++;
338		}
339		break;
340
341	case INTR_NOACK:			/* xfer terminated by master */
342		break;
343
344	case INTR_TRANSMIT:
345		*ptr = 0xff;					/* XXX */
346	  	break;
347
348	case INTR_ERROR:
349		sc->ic_iferrs ++;
350		break;
351
352	default:
353		panic("%s: unknown event (%d)!", __func__, event);
354	}
355
356	splx(s);
357	return;
358}
359
360/*
361 * icoutput()
362 */
363static int
364icoutput(struct ifnet *ifp, struct mbuf *m,
365	struct sockaddr *dst, struct rtentry *rt)
366{
367	device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
368	device_t parent = device_get_parent(icdev);
369	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
370
371	int s, len, sent;
372	struct mbuf *mm;
373	u_char *cp;
374	u_int hdr = dst->sa_family;
375
376	ifp->if_flags |= IFF_RUNNING;
377
378	s = splhigh();
379
380	/* already sending? */
381	if (sc->ic_sending) {
382		ifp->if_oerrors ++;
383		goto error;
384	}
385
386	/* insert header */
387	bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
388
389	cp = sc->ic_obuf + ICHDRLEN;
390	len = 0;
391	mm = m;
392	do {
393		if (len + mm->m_len > sc->ic_if.if_mtu) {
394			/* packet to large */
395			ifp->if_oerrors ++;
396			goto error;
397		}
398
399		bcopy(mtod(mm,char *), cp, mm->m_len);
400		cp += mm->m_len;
401		len += mm->m_len;
402
403	} while ((mm = mm->m_next));
404
405	if (ifp->if_bpf) {
406		struct mbuf m0, *n = m;
407
408		/*
409		 * We need to prepend the address family as
410		 * a four byte field.  Cons up a dummy header
411		 * to pacify bpf.  This is safe because bpf
412		 * will only read from the mbuf (i.e., it won't
413		 * try to free it or keep a pointer a to it).
414		 */
415		m0.m_next = m;
416		m0.m_len = sizeof(u_int);
417		m0.m_data = (char *)&hdr;
418		n = &m0;
419
420		BPF_MTAP(ifp, n);
421	}
422
423	sc->ic_sending = 1;
424
425	m_freem(m);
426	splx(s);
427
428	/* send the packet */
429	if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
430				len + ICHDRLEN, &sent))
431
432		ifp->if_oerrors ++;
433	else {
434		ifp->if_opackets ++;
435		ifp->if_obytes += len;
436	}
437
438	sc->ic_sending = 0;
439
440	return (0);
441
442error:
443	m_freem(m);
444	splx(s);
445
446	return(0);
447}
448
449DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
450MODULE_DEPEND(ic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
451MODULE_VERSION(ic, 1);
452