if_ic.c revision 147256 
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 147256 2005-06-10 16:49:24Z brooks $");
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_int32_t)
70#define ICMTU		1500		/* default mtu */
71
72struct ic_softc {
73	struct ifnet *ic_ifp;
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;
133
134	ifp = sc->ic_ifp = if_alloc(IFT_PARA);
135	if (ifp == NULL) {
136		return (ENOSPC);
137	}
138
139	sc->ic_addr = PCF_MASTER_ADDRESS;	/* XXX only PCF masters */
140
141	ifp->if_softc = sc;
142	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
143	ifp->if_mtu = ICMTU;
144	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST |
145	    IFF_NEEDSGIANT;
146	ifp->if_ioctl = icioctl;
147	ifp->if_output = icoutput;
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	bpfattach(ifp, DLT_NULL, ICHDRLEN);
155
156	return (0);
157}
158
159/*
160 * iciotcl()
161 */
162static int
163icioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
164{
165    device_t icdev = devclass_get_device(ic_devclass, ifp->if_dunit);
166    device_t parent = device_get_parent(icdev);
167    struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
168
169    struct ifaddr *ifa = (struct ifaddr *)data;
170    struct ifreq *ifr = (struct ifreq *)data;
171
172    u_char *iptr, *optr;
173    int error;
174
175    switch (cmd) {
176
177    case SIOCSIFDSTADDR:
178    case SIOCAIFADDR:
179    case SIOCSIFADDR:
180	if (ifa->ifa_addr->sa_family != AF_INET)
181	    return EAFNOSUPPORT;
182	ifp->if_flags |= IFF_UP;
183	/* FALLTHROUGH */
184    case SIOCSIFFLAGS:
185	if ((!(ifp->if_flags & IFF_UP)) && (ifp->if_flags & IFF_RUNNING)) {
186
187	    /* XXX disable PCF */
188	    ifp->if_flags &= ~IFF_RUNNING;
189
190	    /* IFF_UP is not set, try to release the bus anyway */
191	    iicbus_release_bus(parent, icdev);
192	    break;
193	}
194	if (((ifp->if_flags & IFF_UP)) && (!(ifp->if_flags & IFF_RUNNING))) {
195
196	    if ((error = iicbus_request_bus(parent, icdev, IIC_WAIT|IIC_INTR)))
197		return (error);
198
199	    sc->ic_obuf = malloc(sc->ic_ifp->if_mtu + ICHDRLEN,
200				  M_DEVBUF, M_WAITOK);
201	    if (!sc->ic_obuf) {
202		iicbus_release_bus(parent, icdev);
203		return ENOBUFS;
204	    }
205
206	    sc->ic_ifbuf = malloc(sc->ic_ifp->if_mtu + ICHDRLEN,
207				  M_DEVBUF, M_WAITOK);
208	    if (!sc->ic_ifbuf) {
209		iicbus_release_bus(parent, icdev);
210		return ENOBUFS;
211	    }
212
213	    iicbus_reset(parent, IIC_FASTEST, 0, NULL);
214
215	    ifp->if_flags |= IFF_RUNNING;
216	}
217	break;
218
219    case SIOCSIFMTU:
220	/* save previous buffers */
221	iptr = sc->ic_ifbuf;
222	optr = sc->ic_obuf;
223
224	/* allocate input buffer */
225	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
226	if (!sc->ic_ifbuf) {
227
228	    sc->ic_ifbuf = iptr;
229	    sc->ic_obuf = optr;
230
231	    return ENOBUFS;
232	}
233
234	/* allocate output buffer */
235	sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
236	if (!sc->ic_obuf) {
237
238	    free(sc->ic_ifbuf,M_DEVBUF);
239
240	    sc->ic_ifbuf = iptr;
241	    sc->ic_obuf = optr;
242
243	    return ENOBUFS;
244	}
245
246	if (iptr)
247	    free(iptr,M_DEVBUF);
248
249	if (optr)
250	    free(optr,M_DEVBUF);
251
252	sc->ic_ifp->if_mtu = ifr->ifr_mtu;
253	break;
254
255    case SIOCGIFMTU:
256	ifr->ifr_mtu = sc->ic_ifp->if_mtu;
257	break;
258
259    case SIOCADDMULTI:
260    case SIOCDELMULTI:
261	if (ifr == 0) {
262	    return EAFNOSUPPORT;		/* XXX */
263	}
264	switch (ifr->ifr_addr.sa_family) {
265
266	case AF_INET:
267	    break;
268
269	default:
270	    return EAFNOSUPPORT;
271	}
272	break;
273
274    default:
275	return EINVAL;
276    }
277    return 0;
278}
279
280/*
281 * icintr()
282 */
283static void
284icintr (device_t dev, int event, char *ptr)
285{
286	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
287	int unit = device_get_unit(dev);
288	int s, len;
289	struct mbuf *top;
290
291	s = splhigh();
292
293	switch (event) {
294
295	case INTR_GENERAL:
296	case INTR_START:
297		sc->ic_cp = sc->ic_ifbuf;
298		sc->ic_xfercnt = 0;
299		break;
300
301	case INTR_STOP:
302
303	  /* if any error occured during transfert,
304	   * drop the packet */
305	  if (sc->ic_iferrs)
306	    goto err;
307
308	  if ((len = sc->ic_xfercnt) == 0)
309		break;					/* ignore */
310
311	  if (len <= ICHDRLEN)
312	    goto err;
313
314	  len -= ICHDRLEN;
315	  sc->ic_ifp->if_ipackets ++;
316	  sc->ic_ifp->if_ibytes += len;
317
318	  BPF_TAP(sc->ic_ifp, sc->ic_ifbuf, len + ICHDRLEN);
319
320	  top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, sc->ic_ifp, 0);
321
322	  if (top)
323	    netisr_dispatch(NETISR_IP, top);
324	  break;
325
326	err:
327	  printf("ic%d: errors (%d)!\n", unit, sc->ic_iferrs);
328
329	  sc->ic_iferrs = 0;			/* reset error count */
330	  sc->ic_ifp->if_ierrors ++;
331
332	  break;
333
334	case INTR_RECEIVE:
335		if (sc->ic_xfercnt >= sc->ic_ifp->if_mtu+ICHDRLEN) {
336			sc->ic_iferrs ++;
337
338		} else {
339			*sc->ic_cp++ = *ptr;
340			sc->ic_xfercnt ++;
341		}
342		break;
343
344	case INTR_NOACK:			/* xfer terminated by master */
345		break;
346
347	case INTR_TRANSMIT:
348		*ptr = 0xff;					/* XXX */
349	  	break;
350
351	case INTR_ERROR:
352		sc->ic_iferrs ++;
353		break;
354
355	default:
356		panic("%s: unknown event (%d)!", __func__, event);
357	}
358
359	splx(s);
360	return;
361}
362
363/*
364 * icoutput()
365 */
366static int
367icoutput(struct ifnet *ifp, struct mbuf *m,
368	struct sockaddr *dst, struct rtentry *rt)
369{
370	device_t icdev = devclass_get_device(ic_devclass, ifp->if_dunit);
371	device_t parent = device_get_parent(icdev);
372	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
373
374	int s, len, sent;
375	struct mbuf *mm;
376	u_char *cp;
377	u_int32_t hdr = dst->sa_family;
378
379	ifp->if_flags |= IFF_RUNNING;
380
381	s = splhigh();
382
383	/* already sending? */
384	if (sc->ic_sending) {
385		ifp->if_oerrors ++;
386		goto error;
387	}
388
389	/* insert header */
390	bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
391
392	cp = sc->ic_obuf + ICHDRLEN;
393	len = 0;
394	mm = m;
395	do {
396		if (len + mm->m_len > sc->ic_ifp->if_mtu) {
397			/* packet to large */
398			ifp->if_oerrors ++;
399			goto error;
400		}
401
402		bcopy(mtod(mm,char *), cp, mm->m_len);
403		cp += mm->m_len;
404		len += mm->m_len;
405
406	} while ((mm = mm->m_next));
407
408	BPF_MTAP2(ifp, &hdr, sizeof(hdr), m);
409
410	sc->ic_sending = 1;
411
412	m_freem(m);
413	splx(s);
414
415	/* send the packet */
416	if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
417				len + ICHDRLEN, &sent))
418
419		ifp->if_oerrors ++;
420	else {
421		ifp->if_opackets ++;
422		ifp->if_obytes += len;
423	}
424
425	sc->ic_sending = 0;
426
427	return (0);
428
429error:
430	m_freem(m);
431	splx(s);
432
433	return(0);
434}
435
436DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
437MODULE_DEPEND(ic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
438MODULE_VERSION(ic, 1);
439