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: head/sys/dev/iicbus/iic.c 103588 2002-09-19 03:25:46Z peter $
27 *
28 */
29#include <sys/param.h>
30#include <sys/kernel.h>
31#include <sys/systm.h>
32#include <sys/module.h>
33#include <sys/bus.h>
34#include <sys/conf.h>
35#include <sys/uio.h>
36#include <sys/fcntl.h>
37
38#include <dev/iicbus/iiconf.h>
39#include <dev/iicbus/iicbus.h>
40#include <dev/iicbus/iic.h>
41
42#include "iicbus_if.h"
43
44#define BUFSIZE 1024
45
46struct iic_softc {
47
48 u_char sc_addr; /* 7 bit address on iicbus */
49 int sc_count; /* >0 if device opened */
50
51 char sc_buffer[BUFSIZE]; /* output buffer */
52 char sc_inbuf[BUFSIZE]; /* input buffer */
53
54 dev_t sc_devnode;
55};
56
57#define IIC_SOFTC(unit) \
58 ((struct iic_softc *)devclass_get_softc(iic_devclass, (unit)))
59
60#define IIC_DEVICE(unit) \
61 (devclass_get_device(iic_devclass, (unit)))
62
63static int iic_probe(device_t);
64static int iic_attach(device_t);
65static int iic_detach(device_t);
66static void iic_identify(driver_t *driver, device_t parent);
67
68static devclass_t iic_devclass;
69
70static 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 { 0, 0 }
81};
82
83static driver_t iic_driver = {
84 "iic",
85 iic_methods,
86 sizeof(struct iic_softc),
87};
88
89static d_open_t iicopen;
90static d_close_t iicclose;
91static d_write_t iicwrite;
92static d_read_t iicread;
93static d_ioctl_t iicioctl;
94
95#define CDEV_MAJOR 105
96static struct cdevsw iic_cdevsw = {
97 /* open */ iicopen,
98 /* close */ iicclose,
99 /* read */ iicread,
100 /* write */ iicwrite,
101 /* ioctl */ iicioctl,
102 /* poll */ nopoll,
103 /* mmap */ nommap,
104 /* strategy */ nostrategy,
105 /* name */ "iic",
106 /* maj */ CDEV_MAJOR,
107 /* dump */ nodump,
108 /* psize */ nopsize,
109 /* flags */ 0,
110};
111
112static void
113iic_identify(driver_t *driver, device_t parent)
114{
115 BUS_ADD_CHILD(parent, 0, "iic", 0);
116}
117
118static int
119iic_probe(device_t dev)
120{
121 device_set_desc(dev, "I2C generic I/O");
122 return (0);
123}
124
125static int
126iic_attach(device_t dev)
127{
128 struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
129
130 if (!sc)
131 return (ENOMEM);
132
133 bzero(sc, sizeof(struct iic_softc));
134
135 sc->sc_devnode = make_dev(&iic_cdevsw, device_get_unit(dev),
136 UID_ROOT, GID_WHEEL,
137 0600, "iic%d", device_get_unit(dev));
138
139 return (0);
140}
141
142static int
143iic_detach(device_t dev)
144{
145 struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
146
147 if (sc->sc_devnode)
148 destroy_dev(sc->sc_devnode);
149
150 return (0);
151}
152
153static int
154iicopen (dev_t dev, int flags, int fmt, struct thread *td)
155{
156 struct iic_softc *sc = IIC_SOFTC(minor(dev));
157
158 if (!sc)
159 return (EINVAL);
160
161 if (sc->sc_count > 0)
162 return (EBUSY);
163
164 sc->sc_count++;
165
166 return (0);
167}
168
169static int
170iicclose(dev_t dev, int flags, int fmt, struct thread *td)
171{
172 struct iic_softc *sc = IIC_SOFTC(minor(dev));
173
174 if (!sc)
175 return (EINVAL);
176
177 if (!sc->sc_count)
178 return (EINVAL);
179
180 sc->sc_count--;
181
182 if (sc->sc_count < 0)
183 panic("%s: iic_count < 0!", __func__);
184
185 return (0);
186}
187
188static int
189iicwrite(dev_t dev, struct uio * uio, int ioflag)
190{
191 device_t iicdev = IIC_DEVICE(minor(dev));
192 struct iic_softc *sc = IIC_SOFTC(minor(dev));
193 int sent, error, count;
194
195 if (!sc || !iicdev || !sc->sc_addr)
196 return (EINVAL);
197
198 if (sc->sc_count == 0)
199 return (EINVAL);
200
201 if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
202 return (error);
203
204 count = min(uio->uio_resid, BUFSIZE);
205 uiomove(sc->sc_buffer, count, uio);
206
207 error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr,
208 sc->sc_buffer, count, &sent);
209
210 iicbus_release_bus(device_get_parent(iicdev), iicdev);
211
212 return(error);
213}
214
215static int
216iicread(dev_t dev, struct uio * uio, int ioflag)
217{
218 device_t iicdev = IIC_DEVICE(minor(dev));
219 struct iic_softc *sc = IIC_SOFTC(minor(dev));
220 int len, error = 0;
221 int bufsize;
222
223 if (!sc || !iicdev || !sc->sc_addr)
224 return (EINVAL);
225
226 if (sc->sc_count == 0)
227 return (EINVAL);
228
229 if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
230 return (error);
231
232 /* max amount of data to read */
233 len = min(uio->uio_resid, BUFSIZE);
234
235 if ((error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr,
236 sc->sc_inbuf, len, &bufsize)))
237 return (error);
238
239 if (bufsize > uio->uio_resid)
240 panic("%s: too much data read!", __func__);
241
242 iicbus_release_bus(device_get_parent(iicdev), iicdev);
243
244 return (uiomove(sc->sc_inbuf, bufsize, uio));
245}
246
247static int
248iicioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
249{
250 device_t iicdev = IIC_DEVICE(minor(dev));
251 struct iic_softc *sc = IIC_SOFTC(minor(dev));
252 device_t parent = device_get_parent(iicdev);
253 struct iiccmd *s = (struct iiccmd *)data;
254 int error, count;
255
256 if (!sc)
257 return (EINVAL);
258
259 if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev,
260 (flags & O_NONBLOCK) ? IIC_DONTWAIT :
261 (IIC_WAIT | IIC_INTR))))
262 return (error);
263
264 switch (cmd) {
265 case I2CSTART:
266 error = iicbus_start(parent, s->slave, 0);
267
268 /*
269 * Implicitly set the chip addr to the slave addr passed as
270 * parameter. Consequently, start/stop shall be called before
271 * the read or the write of a block.
272 */
273 if (!error)
274 sc->sc_addr = s->slave;
275
276 break;
277
278 case I2CSTOP:
279 error = iicbus_stop(parent);
280 break;
281
282 case I2CRSTCARD:
283 error = iicbus_reset(parent, 0, 0, NULL);
284 break;
285
286 case I2CWRITE:
287 error = iicbus_write(parent, s->buf, s->count, &count, 10);
288 break;
289
290 case I2CREAD:
291 error = iicbus_read(parent, s->buf, s->count, &count, s->last, 10);
292 break;
293
294 default:
295 error = ENODEV;
296 }
297
298 iicbus_release_bus(device_get_parent(iicdev), iicdev);
299
300 return (error);
301}
302
303DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, 0, 0);
304MODULE_DEPEND(iic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
305MODULE_VERSION(iic, 1);