iic.c revision 38813 
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 1.1.1.1 1998/09/03 20:51:50 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
39#include <machine/clock.h>
40
41#include <dev/iicbus/iiconf.h>
42#include <dev/iicbus/iicbus.h>
43#include <machine/iic.h>
44
45#include "iicbus_if.h"
46
47#define BUFSIZE 1024
48
49struct iic_softc {
50
51	u_char sc_addr;			/* 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
58#define IIC_SOFTC(unit) \
59	((struct iic_softc *)devclass_get_softc(iic_devclass, (unit)))
60
61#define IIC_DEVICE(unit) \
62	(devclass_get_device(iic_devclass, (unit)))
63
64static int iic_probe(device_t);
65static int iic_attach(device_t);
66
67static devclass_t iic_devclass;
68
69static device_method_t iic_methods[] = {
70	/* device interface */
71	DEVMETHOD(device_probe,		iic_probe),
72	DEVMETHOD(device_attach,	iic_attach),
73
74	/* iicbus interface */
75	DEVMETHOD(iicbus_intr,		iicbus_generic_intr),
76
77	{ 0, 0 }
78};
79
80static driver_t iic_driver = {
81	"iic",
82	iic_methods,
83	DRIVER_TYPE_MISC,
84	sizeof(struct iic_softc),
85};
86
87static	d_open_t	iicopen;
88static	d_close_t	iicclose;
89static	d_write_t	iicwrite;
90static	d_read_t	iicread;
91static	d_ioctl_t	iicioctl;
92
93#define CDEV_MAJOR 25
94static struct cdevsw iic_cdevsw =
95	{ iicopen,	iicclose,	iicread,	iicwrite,	/*25*/
96	  iicioctl,	nullstop,	nullreset,	nodevtotty,	/*iic*/
97	  seltrue,	nommap,		nostrat,	"iic",	NULL,	-1 };
98
99/*
100 * iicprobe()
101 */
102static int
103iic_probe(device_t dev)
104{
105	struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
106
107	sc->sc_addr = iicbus_get_addr(dev);
108
109	/* XXX detect chip with start/stop conditions */
110
111	return (0);
112}
113
114/*
115 * iicattach()
116 */
117static int
118iic_attach(device_t dev)
119{
120	struct iic_softc *sc = (struct iic_softc *)device_get_softc(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	count = min(uio->uio_resid, BUFSIZE);
174	uiomove(sc->sc_buffer, count, uio);
175
176	error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr,
177					sc->sc_buffer, count, &sent);
178
179	return(error);
180}
181
182static int
183iicread(dev_t dev, struct uio * uio, int ioflag)
184{
185	device_t iicdev = IIC_DEVICE(minor(dev));
186	struct iic_softc *sc = IIC_SOFTC(minor(dev));
187	int len, error = 0;
188	int bufsize;
189
190	if (!sc || !iicdev)
191		return (EINVAL);
192
193	if (sc->sc_count == 0)
194		return (EINVAL);
195
196	/* max amount of data to read */
197	len = min(uio->uio_resid, BUFSIZE);
198
199	if ((error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr,
200					sc->sc_inbuf, len, &bufsize)))
201		return (error);
202
203	if (bufsize > uio->uio_resid)
204		panic("%s: too much data read!", __FUNCTION__);
205
206	return (uiomove(sc->sc_inbuf, bufsize, uio));
207}
208
209static int
210iicioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
211{
212	device_t iicdev = IIC_DEVICE(minor(dev));
213	struct iic_softc *sc = IIC_SOFTC(minor(dev));
214	int error;
215	device_t parent = device_get_parent(iicdev);
216
217	if (!sc)
218		return (EINVAL);
219
220	switch (cmd) {
221	case I2CSTART:
222		error = iicbus_start(parent, sc->sc_addr);
223		break;
224
225	case I2CSTOP:
226		error = iicbus_stop(parent);
227		break;
228
229	case I2CRSTCARD:
230		error = iicbus_reset(parent, 0);
231		break;
232
233	default:
234		error = ENODEV;
235	}
236
237	return (error);
238}
239
240static int iic_devsw_installed = 0;
241
242static void
243iic_drvinit(void *unused)
244{
245        dev_t dev;
246
247        if( ! iic_devsw_installed ) {
248                dev = makedev(CDEV_MAJOR,0);
249                cdevsw_add(&dev,&iic_cdevsw,NULL);
250                iic_devsw_installed = 1;
251        }
252}
253
254CDEV_DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, CDEV_MAJOR,
255			iic_cdevsw, 0, 0);
256#if 0
257SYSINIT(iicdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,iic_drvinit,NULL)
258#endif
259