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: src/sys/dev/iicbus/iic.c,v 1.43 2009/01/26 13:53:39 raj Exp $
27 */
28
29 #include <sys/param.h>
30 #include <sys/buf.h>
31 #include <sys/bus.h>
32 #include <sys/conf.h>
33 #include <sys/fcntl.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/module.h>
37 #include <sys/systm.h>
38 #include <sys/uio.h>
39
40 #include <bus/iicbus/iiconf.h>
41 #include <bus/iicbus/iicbus.h>
42 #include <bus/iicbus/iic.h>
43
44 #include "iicbus_if.h"
45
46 #define BUFSIZE 1024
47
48 struct iic_softc {
49
50 device_t sc_dev;
51 u_char sc_addr; /* 7 bit address on iicbus */
52 int sc_count; /* >0 if device opened */
53
54 char sc_buffer[BUFSIZE]; /* output buffer */
55 char sc_inbuf[BUFSIZE]; /* input buffer */
56
57 cdev_t sc_devnode;
58 };
59
60 #define IIC_LOCK(sc)
61 #define IIC_UNLOCK(sc)
62
63 static int iic_probe(device_t);
64 static int iic_attach(device_t);
65 static int iic_detach(device_t);
66 static void iic_identify(driver_t *driver, device_t parent);
67
68 static devclass_t iic_devclass;
69
70 static device_method_t iic_methods[] = {
71 /* device interface */
72 DEVMETHOD(device_identify, iic_identify),
73 DEVMETHOD(device_probe, iic_probe),
74 DEVMETHOD(device_attach, iic_attach),
75 DEVMETHOD(device_detach, iic_detach),
76
77 /* iicbus interface */
78 DEVMETHOD(iicbus_intr, iicbus_generic_intr),
79
80 DEVMETHOD_END
81 };
82
83 static driver_t iic_driver = {
84 "iic",
85 iic_methods,
86 sizeof(struct iic_softc),
87 };
88
89 static d_open_t iicopen;
90 static d_close_t iicclose;
91 static d_write_t iicwrite;
92 static d_read_t iicread;
93 static d_ioctl_t iicioctl;
94
95 static struct dev_ops iic_ops = {
96 { "iic", 0, 0 },
97 .d_open = iicopen,
98 .d_close = iicclose,
99 .d_read = iicread,
100 .d_write = iicwrite,
101 .d_ioctl = iicioctl,
102 };
103
104 static void
iic_identify(driver_t * driver,device_t parent)105 iic_identify(driver_t *driver, device_t parent)
106 {
107
108 if (device_find_child(parent, "iic", -1) == NULL)
109 BUS_ADD_CHILD(parent, parent, 0, "iic", -1);
110 }
111
112 static int
iic_probe(device_t dev)113 iic_probe(device_t dev)
114 {
115 if (iicbus_get_addr(dev) > 0)
116 return (ENXIO);
117
118 device_set_desc(dev, "I2C generic I/O");
119
120 return (0);
121 }
122
123 static int
iic_attach(device_t dev)124 iic_attach(device_t dev)
125 {
126 struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
127
128 sc->sc_devnode = make_dev(&iic_ops, device_get_unit(dev),
129 UID_ROOT, GID_WHEEL,
130 0600, "iic%d", device_get_unit(dev));
131 if (sc->sc_devnode == NULL) {
132 device_printf(dev, "failed to create character device\n");
133 return (ENXIO);
134 }
135 sc->sc_devnode->si_drv1 = sc;
136
137 return (0);
138 }
139
140 static int
iic_detach(device_t dev)141 iic_detach(device_t dev)
142 {
143 struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
144
145 if (sc->sc_devnode)
146 dev_ops_remove_minor(&iic_ops, device_get_unit(dev));
147
148 return (0);
149 }
150
151 static int
iicopen(struct dev_open_args * ap)152 iicopen(struct dev_open_args *ap)
153 {
154 cdev_t dev = ap->a_head.a_dev;
155 struct iic_softc *sc = dev->si_drv1;
156
157 IIC_LOCK(sc);
158 if (sc->sc_count > 0) {
159 IIC_UNLOCK(sc);
160 return (EBUSY);
161 }
162
163 sc->sc_count++;
164 IIC_UNLOCK(sc);
165
166 return (0);
167 }
168
169 static int
iicclose(struct dev_close_args * ap)170 iicclose(struct dev_close_args *ap)
171 {
172 cdev_t dev = ap->a_head.a_dev;
173 struct iic_softc *sc = dev->si_drv1;
174
175 IIC_LOCK(sc);
176 if (!sc->sc_count) {
177 /* XXX: I don't think this can happen. */
178 IIC_UNLOCK(sc);
179 return (EINVAL);
180 }
181
182 sc->sc_count--;
183
184 if (sc->sc_count < 0)
185 panic("%s: iic_count < 0!", __func__);
186 IIC_UNLOCK(sc);
187
188 return (0);
189 }
190
191 static int
iicwrite(struct dev_write_args * ap)192 iicwrite(struct dev_write_args *ap)
193 {
194 cdev_t dev = ap->a_head.a_dev;
195 struct uio *uio = ap->a_uio;
196 struct iic_softc *sc = dev->si_drv1;
197 device_t iicdev = sc->sc_dev;
198 int sent, error, count;
199
200 IIC_LOCK(sc);
201 if (!sc->sc_addr) {
202 IIC_UNLOCK(sc);
203 return (EINVAL);
204 }
205
206 if (sc->sc_count == 0) {
207 /* XXX: I don't think this can happen. */
208 IIC_UNLOCK(sc);
209 return (EINVAL);
210 }
211
212 error = iicbus_request_bus(device_get_parent(iicdev), iicdev,
213 IIC_DONTWAIT);
214 if (error) {
215 IIC_UNLOCK(sc);
216 return (error);
217 }
218
219 count = (int)szmin(uio->uio_resid, BUFSIZE);
220 uiomove(sc->sc_buffer, (size_t)count, uio);
221
222 error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr,
223 sc->sc_buffer, count, &sent);
224
225 iicbus_release_bus(device_get_parent(iicdev), iicdev);
226 IIC_UNLOCK(sc);
227
228 return (error);
229 }
230
231 static int
iicread(struct dev_read_args * ap)232 iicread(struct dev_read_args *ap)
233 {
234 cdev_t dev = ap->a_head.a_dev;
235 struct uio *uio = ap->a_uio;
236 struct iic_softc *sc = dev->si_drv1;
237 device_t iicdev = sc->sc_dev;
238 int len, error = 0;
239 int bufsize;
240
241 IIC_LOCK(sc);
242 if (!sc->sc_addr) {
243 IIC_UNLOCK(sc);
244 return (EINVAL);
245 }
246
247 if (sc->sc_count == 0) {
248 /* XXX: I don't think this can happen. */
249 IIC_UNLOCK(sc);
250 return (EINVAL);
251 }
252
253 error = iicbus_request_bus(device_get_parent(iicdev), iicdev,
254 IIC_DONTWAIT);
255 if (error) {
256 IIC_UNLOCK(sc);
257 return (error);
258 }
259
260 /* max amount of data to read */
261 len = (int)szmin(uio->uio_resid, BUFSIZE);
262
263 error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr,
264 sc->sc_inbuf, len, &bufsize);
265 if (error) {
266 IIC_UNLOCK(sc);
267 return (error);
268 }
269
270 if (bufsize > uio->uio_resid)
271 panic("%s: too much data read!", __func__);
272
273 iicbus_release_bus(device_get_parent(iicdev), iicdev);
274
275 error = uiomove(sc->sc_inbuf, (size_t)bufsize, uio);
276 IIC_UNLOCK(sc);
277 return (error);
278 }
279
280 static int
iicioctl(struct dev_ioctl_args * ap)281 iicioctl(struct dev_ioctl_args *ap)
282 {
283 cdev_t dev = ap->a_head.a_dev;
284 u_long cmd = ap->a_cmd;
285 caddr_t data = ap->a_data;
286 int flags = ap->a_fflag;
287 struct iic_softc *sc = dev->si_drv1;
288 device_t iicdev = sc->sc_dev;
289 device_t parent = device_get_parent(iicdev);
290 struct iiccmd *s = (struct iiccmd *)data;
291 struct iic_rdwr_data *d = (struct iic_rdwr_data *)data;
292 struct iic_msg *m;
293 int error, count, i;
294 char *buf = NULL;
295 void **usrbufs = NULL;
296
297 if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev,
298 (flags & O_NONBLOCK) ? IIC_DONTWAIT :
299 (IIC_WAIT | IIC_INTR))))
300 return (error);
301
302 switch (cmd) {
303 case I2CSTART:
304 IIC_LOCK(sc);
305 error = iicbus_start(parent, s->slave, 0);
306
307 /*
308 * Implicitly set the chip addr to the slave addr passed as
309 * parameter. Consequently, start/stop shall be called before
310 * the read or the write of a block.
311 */
312 if (!error)
313 sc->sc_addr = s->slave;
314 IIC_UNLOCK(sc);
315
316 break;
317
318 case I2CSTOP:
319 error = iicbus_stop(parent);
320 break;
321
322 case I2CRSTCARD:
323 error = iicbus_reset(parent, IIC_UNKNOWN, 0, NULL);
324 break;
325
326 case I2CWRITE:
327 if (s->count <= 0) {
328 error = EINVAL;
329 break;
330 }
331 buf = kmalloc((unsigned long)s->count, M_TEMP, M_WAITOK);
332 error = copyin(s->buf, buf, s->count);
333 if (error)
334 break;
335 error = iicbus_write(parent, buf, s->count, &count, 10);
336 break;
337
338 case I2CREAD:
339 if (s->count <= 0) {
340 error = EINVAL;
341 break;
342 }
343 buf = kmalloc((unsigned long)s->count, M_TEMP, M_WAITOK);
344 error = iicbus_read(parent, buf, s->count, &count, s->last, 10);
345 if (error)
346 break;
347 error = copyout(buf, s->buf, s->count);
348 break;
349
350 case I2CRDWR:
351 buf = kmalloc(sizeof(*d->msgs) * d->nmsgs, M_TEMP, M_WAITOK);
352 usrbufs = kmalloc(sizeof(void *) * d->nmsgs, M_TEMP, M_ZERO | M_WAITOK);
353 error = copyin(d->msgs, buf, sizeof(*d->msgs) * d->nmsgs);
354 if (error)
355 break;
356 /* Alloc kernel buffers for userland data, copyin write data */
357 for (i = 0; i < d->nmsgs; i++) {
358 m = &((struct iic_msg *)buf)[i];
359 usrbufs[i] = m->buf;
360 m->buf = kmalloc(m->len, M_TEMP, M_WAITOK);
361 if (!(m->flags & IIC_M_RD))
362 copyin(usrbufs[i], m->buf, m->len);
363 }
364 error = iicbus_transfer(parent, (struct iic_msg *)buf, d->nmsgs);
365 /* Copyout all read segments, free up kernel buffers */
366 for (i = 0; i < d->nmsgs; i++) {
367 m = &((struct iic_msg *)buf)[i];
368 if (m->flags & IIC_M_RD)
369 copyout(m->buf, usrbufs[i], m->len);
370 kfree(m->buf, M_TEMP);
371 }
372 kfree(usrbufs, M_TEMP);
373 break;
374
375 case I2CRPTSTART:
376 error = iicbus_repeated_start(parent, s->slave, 0);
377 break;
378
379 default:
380 error = ENOTTY;
381 }
382
383 iicbus_release_bus(device_get_parent(iicdev), iicdev);
384
385 if (buf != NULL)
386 kfree(buf, M_TEMP);
387 return (error);
388 }
389
390 DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, NULL, NULL);
391 MODULE_DEPEND(iic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
392 MODULE_VERSION(iic, 1);
393