if_ic.c revision 161516 
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 161516 2006-08-21 17:32:50Z imp $");
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	sc->ic_addr = PCF_MASTER_ADDRESS;	/* XXX only PCF masters */
139
140	ifp->if_softc = sc;
141	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
142	ifp->if_mtu = ICMTU;
143	ifp->if_flags = IFF_SIMPLEX | IFF_POINTOPOINT | IFF_MULTICAST |
144	    IFF_NEEDSGIANT;
145	ifp->if_ioctl = icioctl;
146	ifp->if_output = icoutput;
147	ifp->if_hdrlen = 0;
148	ifp->if_addrlen = 0;
149	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
150
151	if_attach(ifp);
152
153	bpfattach(ifp, DLT_NULL, ICHDRLEN);
154
155	return (0);
156}
157
158/*
159 * iciotcl()
160 */
161static int
162icioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
163{
164	device_t icdev = devclass_get_device(ic_devclass, ifp->if_dunit);
165	device_t parent = device_get_parent(icdev);
166	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
167
168	struct ifaddr *ifa = (struct ifaddr *)data;
169	struct ifreq *ifr = (struct ifreq *)data;
170
171	u_char *iptr, *optr;
172	int error;
173
174	switch (cmd) {
175
176	case SIOCSIFDSTADDR:
177	case SIOCAIFADDR:
178	case SIOCSIFADDR:
179		if (ifa->ifa_addr->sa_family != AF_INET)
180			return (EAFNOSUPPORT);
181		ifp->if_flags |= IFF_UP;
182		/* FALLTHROUGH */
183	case SIOCSIFFLAGS:
184		if ((!(ifp->if_flags & IFF_UP)) &&
185		    (ifp->if_drv_flags & IFF_DRV_RUNNING)) {
186
187			/* XXX disable PCF */
188			ifp->if_drv_flags &= ~IFF_DRV_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)) &&
195		    (!(ifp->if_drv_flags & IFF_DRV_RUNNING))) {
196			if ((error = iicbus_request_bus(parent, icdev,
197			    IIC_WAIT | IIC_INTR)))
198				return (error);
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			sc->ic_ifbuf = malloc(sc->ic_ifp->if_mtu + ICHDRLEN,
206			    M_DEVBUF, M_WAITOK);
207			if (!sc->ic_ifbuf) {
208				iicbus_release_bus(parent, icdev);
209				return (ENOBUFS);
210			}
211			iicbus_reset(parent, IIC_FASTEST, 0, NULL);
212			ifp->if_drv_flags |= IFF_DRV_RUNNING;
213		}
214		break;
215
216	case SIOCSIFMTU:
217		/* save previous buffers */
218		iptr = sc->ic_ifbuf;
219		optr = sc->ic_obuf;
220
221		/* allocate input buffer */
222		sc->ic_ifbuf = malloc(ifr->ifr_mtu+ICHDRLEN, M_DEVBUF, M_NOWAIT);
223		if (!sc->ic_ifbuf) {
224			sc->ic_ifbuf = iptr;
225			sc->ic_obuf = optr;
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			free(sc->ic_ifbuf,M_DEVBUF);
233			sc->ic_ifbuf = iptr;
234			sc->ic_obuf = optr;
235			return (ENOBUFS);
236		}
237
238		if (iptr)
239			free(iptr,M_DEVBUF);
240		if (optr)
241			free(optr,M_DEVBUF);
242		sc->ic_ifp->if_mtu = ifr->ifr_mtu;
243		break;
244
245	case SIOCGIFMTU:
246		ifr->ifr_mtu = sc->ic_ifp->if_mtu;
247		break;
248
249	case SIOCADDMULTI:
250	case SIOCDELMULTI:
251		if (ifr == 0)
252			return (EAFNOSUPPORT);		/* XXX */
253		switch (ifr->ifr_addr.sa_family) {
254		case AF_INET:
255			break;
256		default:
257			return (EAFNOSUPPORT);
258		}
259		break;
260	default:
261		return (EINVAL);
262	}
263	return (0);
264}
265
266/*
267 * icintr()
268 */
269static void
270icintr(device_t dev, int event, char *ptr)
271{
272	struct ic_softc *sc = (struct ic_softc *)device_get_softc(dev);
273	int unit = device_get_unit(dev);
274	int s, len;
275	struct mbuf *top;
276
277	s = splhigh();
278
279	switch (event) {
280
281	case INTR_GENERAL:
282	case INTR_START:
283		sc->ic_cp = sc->ic_ifbuf;
284		sc->ic_xfercnt = 0;
285		break;
286
287	case INTR_STOP:
288
289		/* if any error occured during transfert,
290		 * drop the packet */
291		if (sc->ic_iferrs)
292			goto err;
293		if ((len = sc->ic_xfercnt) == 0)
294			break;					/* ignore */
295		if (len <= ICHDRLEN)
296			goto err;
297		len -= ICHDRLEN;
298		sc->ic_ifp->if_ipackets++;
299		sc->ic_ifp->if_ibytes += len;
300		BPF_TAP(sc->ic_ifp, sc->ic_ifbuf, len + ICHDRLEN);
301		top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, sc->ic_ifp, 0);
302		if (top)
303			netisr_dispatch(NETISR_IP, top);
304		break;
305	err:
306		printf("ic%d: errors (%d)!\n", unit, sc->ic_iferrs);
307		sc->ic_iferrs = 0;			/* reset error count */
308		sc->ic_ifp->if_ierrors++;
309		break;
310
311	case INTR_RECEIVE:
312		if (sc->ic_xfercnt >= sc->ic_ifp->if_mtu+ICHDRLEN) {
313			sc->ic_iferrs++;
314		} else {
315			*sc->ic_cp++ = *ptr;
316			sc->ic_xfercnt++;
317		}
318		break;
319
320	case INTR_NOACK:			/* xfer terminated by master */
321		break;
322
323	case INTR_TRANSMIT:
324		*ptr = 0xff;					/* XXX */
325	  	break;
326
327	case INTR_ERROR:
328		sc->ic_iferrs++;
329		break;
330
331	default:
332		panic("%s: unknown event (%d)!", __func__, event);
333	}
334
335	splx(s);
336	return;
337}
338
339/*
340 * icoutput()
341 */
342static int
343icoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
344    struct rtentry *rt)
345{
346	device_t icdev = devclass_get_device(ic_devclass, ifp->if_dunit);
347	device_t parent = device_get_parent(icdev);
348	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
349
350	int s, len, sent;
351	struct mbuf *mm;
352	u_char *cp;
353	u_int32_t hdr;
354
355	/* BPF writes need to be handled specially. */
356	if (dst->sa_family == AF_UNSPEC)
357		bcopy(dst->sa_data, &hdr, sizeof(hdr));
358	else
359		hdr = dst->sa_family;
360
361	ifp->if_drv_flags |= IFF_DRV_RUNNING;
362
363	s = splhigh();
364
365	/* already sending? */
366	if (sc->ic_sending) {
367		ifp->if_oerrors++;
368		goto error;
369	}
370
371	/* insert header */
372	bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
373
374	cp = sc->ic_obuf + ICHDRLEN;
375	len = 0;
376	mm = m;
377	do {
378		if (len + mm->m_len > sc->ic_ifp->if_mtu) {
379			/* packet to large */
380			ifp->if_oerrors++;
381			goto error;
382		}
383
384		bcopy(mtod(mm,char *), cp, mm->m_len);
385		cp += mm->m_len;
386		len += mm->m_len;
387
388	} while ((mm = mm->m_next));
389
390	BPF_MTAP2(ifp, &hdr, sizeof(hdr), m);
391
392	sc->ic_sending = 1;
393
394	m_freem(m);
395	splx(s);
396
397	/* send the packet */
398	if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
399				len + ICHDRLEN, &sent))
400
401		ifp->if_oerrors++;
402	else {
403		ifp->if_opackets++;
404		ifp->if_obytes += len;
405	}
406
407	sc->ic_sending = 0;
408
409	return (0);
410
411error:
412	m_freem(m);
413	splx(s);
414
415	return(0);
416}
417
418DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
419MODULE_DEPEND(ic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
420MODULE_VERSION(ic, 1);
421