xref: /freebsd/sys/dev/iicbus/if_ic.c (revision 3642298923e528d795e3a30ec165d2b469e28b40)
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("$FreeBSD$");
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 
72 struct 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 
88 static devclass_t ic_devclass;
89 
90 static int icprobe(device_t);
91 static int icattach(device_t);
92 
93 static int icioctl(struct ifnet *, u_long, caddr_t);
94 static int icoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
95 		struct rtentry *);
96 
97 static void icintr(device_t, int, char *);
98 
99 static 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 
110 static driver_t ic_driver = {
111 	"ic",
112 	ic_methods,
113 	sizeof(struct ic_softc),
114 };
115 
116 /*
117  * icprobe()
118  */
119 static int
120 icprobe(device_t dev)
121 {
122 	return (0);
123 }
124 
125 /*
126  * icattach()
127  */
128 static int
129 icattach(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  */
162 static int
163 icioctl(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)) &&
186 	  (ifp->if_drv_flags & IFF_DRV_RUNNING)) {
187 
188 	    /* XXX disable PCF */
189 	    ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
190 
191 	    /* IFF_UP is not set, try to release the bus anyway */
192 	    iicbus_release_bus(parent, icdev);
193 	    break;
194 	}
195 	if (((ifp->if_flags & IFF_UP)) &&
196 	  (!(ifp->if_drv_flags & IFF_DRV_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_ifp->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_ifp->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_drv_flags |= IFF_DRV_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_ifp->if_mtu = ifr->ifr_mtu;
255 	break;
256 
257     case SIOCGIFMTU:
258 	ifr->ifr_mtu = sc->ic_ifp->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 	  len -= ICHDRLEN;
317 	  sc->ic_ifp->if_ipackets ++;
318 	  sc->ic_ifp->if_ibytes += len;
319 
320 	  BPF_TAP(sc->ic_ifp, sc->ic_ifbuf, len + ICHDRLEN);
321 
322 	  top = m_devget(sc->ic_ifbuf + ICHDRLEN, len, 0, sc->ic_ifp, 0);
323 
324 	  if (top)
325 	    netisr_dispatch(NETISR_IP, top);
326 	  break;
327 
328 	err:
329 	  printf("ic%d: errors (%d)!\n", unit, sc->ic_iferrs);
330 
331 	  sc->ic_iferrs = 0;			/* reset error count */
332 	  sc->ic_ifp->if_ierrors ++;
333 
334 	  break;
335 
336 	case INTR_RECEIVE:
337 		if (sc->ic_xfercnt >= sc->ic_ifp->if_mtu+ICHDRLEN) {
338 			sc->ic_iferrs ++;
339 
340 		} else {
341 			*sc->ic_cp++ = *ptr;
342 			sc->ic_xfercnt ++;
343 		}
344 		break;
345 
346 	case INTR_NOACK:			/* xfer terminated by master */
347 		break;
348 
349 	case INTR_TRANSMIT:
350 		*ptr = 0xff;					/* XXX */
351 	  	break;
352 
353 	case INTR_ERROR:
354 		sc->ic_iferrs ++;
355 		break;
356 
357 	default:
358 		panic("%s: unknown event (%d)!", __func__, event);
359 	}
360 
361 	splx(s);
362 	return;
363 }
364 
365 /*
366  * icoutput()
367  */
368 static int
369 icoutput(struct ifnet *ifp, struct mbuf *m,
370 	struct sockaddr *dst, struct rtentry *rt)
371 {
372 	device_t icdev = devclass_get_device(ic_devclass, ifp->if_dunit);
373 	device_t parent = device_get_parent(icdev);
374 	struct ic_softc *sc = (struct ic_softc *)device_get_softc(icdev);
375 
376 	int s, len, sent;
377 	struct mbuf *mm;
378 	u_char *cp;
379 	u_int32_t hdr;
380 
381 	/* BPF writes need to be handled specially. */
382 	if (dst->sa_family == AF_UNSPEC)
383 		bcopy(dst->sa_data, &hdr, sizeof(hdr));
384 	else
385 		hdr = dst->sa_family;
386 
387 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
388 
389 	s = splhigh();
390 
391 	/* already sending? */
392 	if (sc->ic_sending) {
393 		ifp->if_oerrors ++;
394 		goto error;
395 	}
396 
397 	/* insert header */
398 	bcopy ((char *)&hdr, sc->ic_obuf, ICHDRLEN);
399 
400 	cp = sc->ic_obuf + ICHDRLEN;
401 	len = 0;
402 	mm = m;
403 	do {
404 		if (len + mm->m_len > sc->ic_ifp->if_mtu) {
405 			/* packet to large */
406 			ifp->if_oerrors ++;
407 			goto error;
408 		}
409 
410 		bcopy(mtod(mm,char *), cp, mm->m_len);
411 		cp += mm->m_len;
412 		len += mm->m_len;
413 
414 	} while ((mm = mm->m_next));
415 
416 	BPF_MTAP2(ifp, &hdr, sizeof(hdr), m);
417 
418 	sc->ic_sending = 1;
419 
420 	m_freem(m);
421 	splx(s);
422 
423 	/* send the packet */
424 	if (iicbus_block_write(parent, sc->ic_addr, sc->ic_obuf,
425 				len + ICHDRLEN, &sent))
426 
427 		ifp->if_oerrors ++;
428 	else {
429 		ifp->if_opackets ++;
430 		ifp->if_obytes += len;
431 	}
432 
433 	sc->ic_sending = 0;
434 
435 	return (0);
436 
437 error:
438 	m_freem(m);
439 	splx(s);
440 
441 	return(0);
442 }
443 
444 DRIVER_MODULE(ic, iicbus, ic_driver, ic_devclass, 0, 0);
445 MODULE_DEPEND(ic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
446 MODULE_VERSION(ic, 1);
447