iic.c revision 46635 
1/*-
2 * Copyright (c) 1998 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 *	$Id: iic.c,v 1.7 1999/02/13 18:01:55 nsouch Exp $
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/buf.h>
36#include <sys/uio.h>
37#include <sys/malloc.h>
38#include <sys/fcntl.h>
39
40#include <machine/clock.h>
41
42#include <dev/iicbus/iiconf.h>
43#include <dev/iicbus/iicbus.h>
44
45#include <machine/iic.h>
46
47#include "iicbus_if.h"
48
49#define BUFSIZE 1024
50
51struct iic_softc {
52
53	u_char sc_addr;			/* address on iicbus */
54	int sc_count;			/* >0 if device opened */
55
56	char sc_buffer[BUFSIZE];	/* output buffer */
57	char sc_inbuf[BUFSIZE];		/* input buffer */
58};
59
60#define IIC_SOFTC(unit) \
61	((struct iic_softc *)devclass_get_softc(iic_devclass, (unit)))
62
63#define IIC_DEVICE(unit) \
64	(devclass_get_device(iic_devclass, (unit)))
65
66static int iic_probe(device_t);
67static int iic_attach(device_t);
68
69static devclass_t iic_devclass;
70
71static device_method_t iic_methods[] = {
72	/* device interface */
73	DEVMETHOD(device_probe,		iic_probe),
74	DEVMETHOD(device_attach,	iic_attach),
75
76	/* iicbus interface */
77	DEVMETHOD(iicbus_intr,		iicbus_generic_intr),
78
79	{ 0, 0 }
80};
81
82static driver_t iic_driver = {
83	"iic",
84	iic_methods,
85	DRIVER_TYPE_MISC,
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	{ iicopen,	iicclose,	iicread,	iicwrite,	/*105*/
98	  iicioctl,	nullstop,	nullreset,	nodevtotty,	/*iic*/
99	  seltrue,	nommap,		nostrat,	"iic",	NULL,	-1 };
100
101/*
102 * iicprobe()
103 */
104static int
105iic_probe(device_t dev)
106{
107	struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
108
109	sc->sc_addr = iicbus_get_addr(dev);
110
111	/* XXX detect chip with start/stop conditions */
112
113	return (0);
114}
115
116/*
117 * iicattach()
118 */
119static int
120iic_attach(device_t dev)
121{
122	return (0);
123}
124
125static int
126iicopen (dev_t dev, int flags, int fmt, struct proc *p)
127{
128	struct iic_softc *sc = IIC_SOFTC(minor(dev));
129
130	if (!sc)
131		return (EINVAL);
132
133	if (sc->sc_count > 0)
134		return (EBUSY);
135
136	sc->sc_count++;
137
138	return (0);
139}
140
141static int
142iicclose(dev_t dev, int flags, int fmt, struct proc *p)
143{
144	struct iic_softc *sc = IIC_SOFTC(minor(dev));
145
146	if (!sc)
147		return (EINVAL);
148
149	if (!sc->sc_count)
150		return (EINVAL);
151
152	sc->sc_count--;
153
154	if (sc->sc_count < 0)
155		panic("%s: iic_count < 0!", __FUNCTION__);
156
157	return (0);
158}
159
160static int
161iicwrite(dev_t dev, struct uio * uio, int ioflag)
162{
163	device_t iicdev = IIC_DEVICE(minor(dev));
164	struct iic_softc *sc = IIC_SOFTC(minor(dev));
165	int sent, error, count;
166
167	if (!sc || !iicdev)
168		return (EINVAL);
169
170	if (sc->sc_count == 0)
171		return (EINVAL);
172
173	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
174		return (error);
175
176	count = min(uio->uio_resid, BUFSIZE);
177	uiomove(sc->sc_buffer, count, uio);
178
179	error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr,
180					sc->sc_buffer, count, &sent);
181
182	iicbus_release_bus(device_get_parent(iicdev), iicdev);
183
184	return(error);
185}
186
187static int
188iicread(dev_t dev, struct uio * uio, int ioflag)
189{
190	device_t iicdev = IIC_DEVICE(minor(dev));
191	struct iic_softc *sc = IIC_SOFTC(minor(dev));
192	int len, error = 0;
193	int bufsize;
194
195	if (!sc || !iicdev)
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	/* max amount of data to read */
205	len = min(uio->uio_resid, BUFSIZE);
206
207	if ((error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr,
208					sc->sc_inbuf, len, &bufsize)))
209		return (error);
210
211	if (bufsize > uio->uio_resid)
212		panic("%s: too much data read!", __FUNCTION__);
213
214	iicbus_release_bus(device_get_parent(iicdev), iicdev);
215
216	return (uiomove(sc->sc_inbuf, bufsize, uio));
217}
218
219static int
220iicioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
221{
222	device_t iicdev = IIC_DEVICE(minor(dev));
223	struct iic_softc *sc = IIC_SOFTC(minor(dev));
224	device_t parent = device_get_parent(iicdev);
225	struct iiccmd *s = (struct iiccmd *)data;
226	int error, count;
227
228	if (!sc)
229		return (EINVAL);
230
231	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev,
232			(flags & O_NONBLOCK) ? IIC_DONTWAIT :
233						(IIC_WAIT | IIC_INTR))))
234		return (error);
235
236	switch (cmd) {
237	case I2CSTART:
238		error = iicbus_start(parent, s->slave, 0);
239		break;
240
241	case I2CSTOP:
242		error = iicbus_stop(parent);
243		break;
244
245	case I2CRSTCARD:
246		error = iicbus_reset(parent, 0, 0, NULL);
247		break;
248
249	case I2CWRITE:
250		error = iicbus_write(parent, s->buf, s->count, &count, 0);
251		break;
252
253	case I2CREAD:
254		error = iicbus_read(parent, s->buf, s->count, &count, s->last, 0);
255		break;
256
257	default:
258		error = ENODEV;
259	}
260
261	iicbus_release_bus(device_get_parent(iicdev), iicdev);
262
263	return (error);
264}
265
266static int iic_devsw_installed = 0;
267
268static void
269iic_drvinit(void *unused)
270{
271        dev_t dev;
272
273        if( ! iic_devsw_installed ) {
274                dev = makedev(CDEV_MAJOR,0);
275                cdevsw_add(&dev,&iic_cdevsw,NULL);
276                iic_devsw_installed = 1;
277        }
278}
279
280DEV_DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, CDEV_MAJOR,
281			NODEV, iic_cdevsw, 0, 0);
282
283SYSINIT(iicdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,iic_drvinit,NULL)
284