if_ic.c revision 119418 
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: head/sys/dev/iicbus/if_ic.c 119418 2003-08-24 17:55:58Z obrien $");
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/module.h>
42#include <sys/bus.h>
43#include <sys/time.h>
44#include <sys/malloc.h>
45
46#include <net/if.h>
47#include <net/if_types.h>
48#include <net/netisr.h>
49
50#include <sys/mbuf.h>
51#include <sys/socket.h>
52#include <net/netisr.h>
53#include <net/route.h>
54#include <netinet/in.h>
55#include <netinet/in_systm.h>
56#include <netinet/in_var.h>
57#include <netinet/ip.h>
58#include <netinet/if_ether.h>
59
60#include <net/bpf.h>
61
62#include <dev/iicbus/iiconf.h>
63#include <dev/iicbus/iicbus.h>
64
65#include "iicbus_if.h"
66
67#define PCF_MASTER_ADDRESS 0xaa
68
69#define ICHDRLEN	sizeof(u_int)
70#define ICMTU		1500		/* default mtu */
71
72struct ic_softc {
73	struct ifnet ic_if;
74
75	u_char ic_addr;			/* peer I2C address */
76
77	int ic_sending;
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
88static devclass_t ic_devclass;
89
90static int icprobe(device_t);
91static int icattach(device_t);
92
93static int icioctl(struct ifnet *, u_long, caddr_t);
94static int icoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
95		struct rtentry *);
96
97static void icintr(device_t, int, char *);
98
99static device_method_t ic_methods[] = {
100	/* device interface */
101	DEVMETHOD(device_probe,		icprobe),
102	DEVMETHOD(device_attach,	icattach),
103
104	/* iicbus interface */
105	DEVMETHOD(iicbus_intr,		icintr),
106
107	{ 0, 0 }
108};
109
110static driver_t ic_driver = {
111	"ic",
112	ic_methods,
113	sizeof(struct ic_softc),
114};
115
116/*
117 * icprobe()
118 */
119static int
120icprobe(device_t dev)
121{
122	return (0);
123}
124
125/*
126 * icattach()
127 */
128static int
129icattach(device_t dev)
130{
131	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
132	struct ifnet *ifp = &sc->ic_if;
133
134	sc->ic_addr = PCF_MASTER_ADDRESS;	/* XXX only PCF masters */
135
136	ifp->if_softc = sc;
137	ifp->if_name = "ic";
138	ifp->if_unit = device_get_unit(dev);
139	ifp->if_mtu = ICMTU;
140	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST;
141	ifp->if_ioctl = icioctl;
142	ifp->if_output = icoutput;
143	ifp->if_type = IFT_PARA;
144	ifp->if_hdrlen = 0;
145	ifp->if_addrlen = 0;
146	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
147
148	if_attach(ifp);
149
150	bpfattach(ifp, DLT_NULL, ICHDRLEN);
151
152	return (0);
153}
154
155/*
156 * iciotcl()
157 */
158static int
159icioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
160{
161    device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
162    device_t parent = device_get_parent(icdev);
163    struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
164
165    struct ifaddr *ifa = (struct ifaddr *)data;
166    struct ifreq *ifr = (struct ifreq *)data;
167
168    u_char *iptr, *optr;
169    int error;
170
171    switch (cmd) {
172
173    case SIOCSIFDSTADDR:
174    case SIOCAIFADDR:
175    case SIOCSIFADDR:
176	if (ifa->ifa_addr->sa_family != AF_INET)
177	    return EAFNOSUPPORT;
178	ifp->if_flags |= IFF_UP;
179	/* FALLTHROUGH */
180    case SIOCSIFFLAGS:
181	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
182
183	    /* XXX disable PCF */
184	    ifp->if_flags &= ~IFF_RUNNING;
185
186	    /* IFF_UP is not set, try to release the bus anyway */
187	    iicbus_release_bus(parent, icdev);
188	    break;
189	}
190	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
191
192	    if ((error = iicbus_request_bus(parent, icdev, IIC_WAIT|IIC_INTR)))
193		return (error);
194
195	    sc->ic_obuf = malloc(sc->ic_if.if_mtu + ICHDRLEN,
196				  M_DEVBUF, M_WAITOK);
197	    if (!sc->ic_obuf) {
198		iicbus_release_bus(parent, icdev);
199		return ENOBUFS;
200	    }
201
202	    sc->ic_ifbuf = malloc(sc->ic_if.if_mtu + ICHDRLEN,
203				  M_DEVBUF, M_WAITOK);
204	    if (!sc->ic_ifbuf) {
205		iicbus_release_bus(parent, icdev);
206		return ENOBUFS;
207	    }
208
209	    iicbus_reset(parent, IIC_FASTEST, 0, NULL);
210
211	    ifp->if_flags |= IFF_RUNNING;
212	}
213	break;
214
215    case SIOCSIFMTU:
216	/* save previous buffers */
217	iptr = sc->ic_ifbuf;
218	optr = sc->ic_obuf;
219
220	/* allocate input buffer */
221	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
222	if (!sc->ic_ifbuf) {
223
224	    sc->ic_ifbuf = iptr;
225	    sc->ic_obuf = optr;
226
227	    return ENOBUFS;
228	}
229
230	/* allocate output buffer */
231	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
232	if (!sc->ic_obuf) {
233
234	    free(sc->ic_ifbuf,M_DEVBUF);
235
236	    sc->ic_ifbuf = iptr;
237	    sc->ic_obuf = optr;
238
239	    return ENOBUFS;
240	}
241
242	if (iptr)
243	    free(iptr,M_DEVBUF);
244
245	if (optr)
246	    free(optr,M_DEVBUF);
247
248	sc->ic_if.if_mtu = ifr->ifr_mtu;
249	break;
250
251    case SIOCGIFMTU:
252	ifr->ifr_mtu = sc->ic_if.if_mtu;
253	break;
254
255    case SIOCADDMULTI:
256    case SIOCDELMULTI:
257	if (ifr == 0) {
258	    return EAFNOSUPPORT;		/* XXX */
259	}
260	switch (ifr->ifr_addr.sa_family) {
261
262	case AF_INET:
263	    break;
264
265	default:
266	    return EAFNOSUPPORT;
267	}
268	break;
269
270    default:
271	return EINVAL;
272    }
273    return 0;
274}
275
276/*
277 * icintr()
278 */
279static void
280icintr (device_t dev, int event, char *ptr)
281{
282	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
283	int unit = device_get_unit(dev);
284	int s, len;
285	struct mbuf *top;
286
287	s = splhigh();
288
289	switch (event) {
290
291	case INTR_GENERAL:
292	case INTR_START:
293		sc->ic_cp = sc->ic_ifbuf;
294		sc->ic_xfercnt = 0;
295		break;
296
297	case INTR_STOP:
298
299	  /* if any error occured during transfert,
300	   * drop the packet */
301	  if (sc->ic_iferrs)
302	    goto err;
303
304	  if ((len = sc->ic_xfercnt) == 0)
305		break;					/* ignore */
306
307	  if (len <= ICHDRLEN)
308	    goto err;
309
310	  len -= ICHDRLEN;
311	  sc->ic_if.if_ipackets ++;
312	  sc->ic_if.if_ibytes += len;
313
314	  BPF_TAP(&sc->ic_if, sc->ic_ifbuf, len + ICHDRLEN);
315
316	  top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, &sc->ic_if, 0);
317
318	  if (top)
319	    netisr_dispatch(NETISR_IP, top);
320	  break;
321
322	err:
323	  printf("ic%d: errors (%d)!\n", unit, sc->ic_iferrs);
324
325	  sc->ic_iferrs = 0;			/* reset error count */
326	  sc->ic_if.if_ierrors ++;
327
328	  break;
329
330	case INTR_RECEIVE:
331		if (sc->ic_xfercnt >= sc->ic_if.if_mtu+ICHDRLEN) {
332			sc->ic_iferrs ++;
333
334		} else {
335			*sc->ic_cp++ = *ptr;
336			sc->ic_xfercnt ++;
337		}
338		break;
339
340	case INTR_NOACK:			/* xfer terminated by master */
341		break;
342
343	case INTR_TRANSMIT:
344		*ptr = 0xff;					/* XXX */
345	  	break;
346
347	case INTR_ERROR:
348		sc->ic_iferrs ++;
349		break;
350
351	default:
352		panic("%s: unknown event (%d)!", __func__, event);
353	}
354
355	splx(s);
356	return;
357}
358
359/*
360 * icoutput()
361 */
362static int
363icoutput(struct ifnet *ifp, struct mbuf *m,
364	struct sockaddr *dst, struct rtentry *rt)
365{
366	device_t icdev = devclass_get_device(ic_devclass, ifp->if_unit);
367	device_t parent = device_get_parent(icdev);
368	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
369
370	int s, len, sent;
371	struct mbuf *mm;
372	u_char *cp;
373	u_int hdr = dst->sa_family;
374
375	ifp->if_flags |= IFF_RUNNING;
376
377	s = splhigh();
378
379	/* already sending? */
380	if (sc->ic_sending) {
381		ifp->if_oerrors ++;
382		goto error;
383	}
384
385	/* insert header */
386	bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
387
388	cp = sc->ic_obuf + ICHDRLEN;
389	len = 0;
390	mm = m;
391	do {
392		if (len + mm->m_len > sc->ic_if.if_mtu) {
393			/* packet to large */
394			ifp->if_oerrors ++;
395			goto error;
396		}
397
398		bcopy(mtod(mm,char *), cp, mm->m_len);
399		cp += mm->m_len;
400		len += mm->m_len;
401
402	} while ((mm = mm->m_next));
403
404	if (ifp->if_bpf) {
405		struct mbuf m0, *n = m;
406
407		/*
408		 * We need to prepend the address family as
409		 * a four byte field.  Cons up a dummy header
410		 * to pacify bpf.  This is safe because bpf
411		 * will only read from the mbuf (i.e., it won't
412		 * try to free it or keep a pointer a to it).
413		 */
414		m0.m_next = m;
415		m0.m_len = sizeof(u_int);
416		m0.m_data = (char *)&hdr;
417		n = &m0;
418
419		BPF_MTAP(ifp, n);
420	}
421
422	sc->ic_sending = 1;
423
424	m_freem(m);
425	splx(s);
426
427	/* send the packet */
428	if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
429				len + ICHDRLEN, &sent))
430
431		ifp->if_oerrors ++;
432	else {
433		ifp->if_opackets ++;
434		ifp->if_obytes += len;
435	}
436
437	sc->ic_sending = 0;
438
439	return (0);
440
441error:
442	m_freem(m);
443	splx(s);
444
445	return(0);
446}
447
448DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
449MODULE_DEPEND(ic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
450MODULE_VERSION(ic, 1);
451