xref: /freebsd/sys/dev/iicbus/iic.c (revision 2ad872c5794e4c26fdf6ed219ad3f09ca0d5304a)
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 1.5 1998/12/07 21:58:16 archie 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 
44 #include <machine/iic.h>
45 
46 #include "iicbus_if.h"
47 
48 #define BUFSIZE 1024
49 
50 struct iic_softc {
51 
52 	u_char sc_addr;			/* address on iicbus */
53 	int sc_count;			/* >0 if device opened */
54 
55 	char sc_buffer[BUFSIZE];	/* output buffer */
56 	char sc_inbuf[BUFSIZE];		/* input buffer */
57 };
58 
59 #define IIC_SOFTC(unit) \
60 	((struct iic_softc *)devclass_get_softc(iic_devclass, (unit)))
61 
62 #define IIC_DEVICE(unit) \
63 	(devclass_get_device(iic_devclass, (unit)))
64 
65 static int iic_probe(device_t);
66 static int iic_attach(device_t);
67 
68 static devclass_t iic_devclass;
69 
70 static device_method_t iic_methods[] = {
71 	/* device interface */
72 	DEVMETHOD(device_probe,		iic_probe),
73 	DEVMETHOD(device_attach,	iic_attach),
74 
75 	/* iicbus interface */
76 	DEVMETHOD(iicbus_intr,		iicbus_generic_intr),
77 
78 	{ 0, 0 }
79 };
80 
81 static driver_t iic_driver = {
82 	"iic",
83 	iic_methods,
84 	DRIVER_TYPE_MISC,
85 	sizeof(struct iic_softc),
86 };
87 
88 static	d_open_t	iicopen;
89 static	d_close_t	iicclose;
90 static	d_write_t	iicwrite;
91 static	d_read_t	iicread;
92 static	d_ioctl_t	iicioctl;
93 
94 #define CDEV_MAJOR 105
95 static struct cdevsw iic_cdevsw =
96 	{ iicopen,	iicclose,	iicread,	iicwrite,	/*105*/
97 	  iicioctl,	nullstop,	nullreset,	nodevtotty,	/*iic*/
98 	  seltrue,	nommap,		nostrat,	"iic",	NULL,	-1 };
99 
100 /*
101  * iicprobe()
102  */
103 static int
104 iic_probe(device_t dev)
105 {
106 	struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
107 
108 	sc->sc_addr = iicbus_get_addr(dev);
109 
110 	/* XXX detect chip with start/stop conditions */
111 
112 	return (0);
113 }
114 
115 /*
116  * iicattach()
117  */
118 static int
119 iic_attach(device_t dev)
120 {
121 	return (0);
122 }
123 
124 static int
125 iicopen (dev_t dev, int flags, int fmt, struct proc *p)
126 {
127 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
128 
129 	if (!sc)
130 		return (EINVAL);
131 
132 	if (sc->sc_count > 0)
133 		return (EBUSY);
134 
135 	sc->sc_count++;
136 
137 	return (0);
138 }
139 
140 static int
141 iicclose(dev_t dev, int flags, int fmt, struct proc *p)
142 {
143 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
144 
145 	if (!sc)
146 		return (EINVAL);
147 
148 	if (!sc->sc_count)
149 		return (EINVAL);
150 
151 	sc->sc_count--;
152 
153 	if (sc->sc_count < 0)
154 		panic("%s: iic_count < 0!", __FUNCTION__);
155 
156 	return (0);
157 }
158 
159 static int
160 iicwrite(dev_t dev, struct uio * uio, int ioflag)
161 {
162 	device_t iicdev = IIC_DEVICE(minor(dev));
163 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
164 	int sent, error, count;
165 
166 	if (!sc || !iicdev)
167 		return (EINVAL);
168 
169 	if (sc->sc_count == 0)
170 		return (EINVAL);
171 
172 	count = min(uio->uio_resid, BUFSIZE);
173 	uiomove(sc->sc_buffer, count, uio);
174 
175 	error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr,
176 					sc->sc_buffer, count, &sent);
177 
178 	return(error);
179 }
180 
181 static int
182 iicread(dev_t dev, struct uio * uio, int ioflag)
183 {
184 	device_t iicdev = IIC_DEVICE(minor(dev));
185 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
186 	int len, error = 0;
187 	int bufsize;
188 
189 	if (!sc || !iicdev)
190 		return (EINVAL);
191 
192 	if (sc->sc_count == 0)
193 		return (EINVAL);
194 
195 	/* max amount of data to read */
196 	len = min(uio->uio_resid, BUFSIZE);
197 
198 	if ((error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr,
199 					sc->sc_inbuf, len, &bufsize)))
200 		return (error);
201 
202 	if (bufsize > uio->uio_resid)
203 		panic("%s: too much data read!", __FUNCTION__);
204 
205 	return (uiomove(sc->sc_inbuf, bufsize, uio));
206 }
207 
208 static int
209 iicioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
210 {
211 	device_t iicdev = IIC_DEVICE(minor(dev));
212 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
213 	device_t parent = device_get_parent(iicdev);
214 	struct iiccmd *s = (struct iiccmd *)data;
215 	int error, count;
216 
217 	if (!sc)
218 		return (EINVAL);
219 
220 	switch (cmd) {
221 	case I2CSTART:
222 		error = iicbus_start(parent, s->slave, 0);
223 		break;
224 
225 	case I2CSTOP:
226 		error = iicbus_stop(parent);
227 		break;
228 
229 	case I2CRSTCARD:
230 		error = iicbus_reset(parent, 0, 0, NULL);
231 		break;
232 
233 	case I2CWRITE:
234 		error = iicbus_write(parent, s->buf, s->count, &count, 0);
235 		break;
236 
237 	case I2CREAD:
238 		error = iicbus_read(parent, s->buf, s->count, &count, s->last, 0);
239 		break;
240 
241 	default:
242 		error = ENODEV;
243 	}
244 
245 	return (error);
246 }
247 
248 static int iic_devsw_installed = 0;
249 
250 static void
251 iic_drvinit(void *unused)
252 {
253         dev_t dev;
254 
255         if( ! iic_devsw_installed ) {
256                 dev = makedev(CDEV_MAJOR,0);
257                 cdevsw_add(&dev,&iic_cdevsw,NULL);
258                 iic_devsw_installed = 1;
259         }
260 }
261 
262 CDEV_DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, CDEV_MAJOR,
263 			iic_cdevsw, 0, 0);
264 
265 SYSINIT(iicdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,iic_drvinit,NULL)
266