xref: /freebsd/sys/dev/iicbus/iic.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
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 1.2 1998/09/04 17:53:35 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 
49 struct 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 
64 static int iic_probe(device_t);
65 static int iic_attach(device_t);
66 
67 static devclass_t iic_devclass;
68 
69 static 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 
80 static driver_t iic_driver = {
81 	"iic",
82 	iic_methods,
83 	DRIVER_TYPE_MISC,
84 	sizeof(struct iic_softc),
85 };
86 
87 static	d_open_t	iicopen;
88 static	d_close_t	iicclose;
89 static	d_write_t	iicwrite;
90 static	d_read_t	iicread;
91 static	d_ioctl_t	iicioctl;
92 
93 #define CDEV_MAJOR 105
94 static struct cdevsw iic_cdevsw =
95 	{ iicopen,	iicclose,	iicread,	iicwrite,	/*105*/
96 	  iicioctl,	nullstop,	nullreset,	nodevtotty,	/*iic*/
97 	  seltrue,	nommap,		nostrat,	"iic",	NULL,	-1 };
98 
99 /*
100  * iicprobe()
101  */
102 static int
103 iic_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  */
117 static int
118 iic_attach(device_t dev)
119 {
120 	struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
121 
122 	return (0);
123 }
124 
125 static int
126 iicopen (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 
141 static int
142 iicclose(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 
160 static int
161 iicwrite(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 
182 static int
183 iicread(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 
209 static int
210 iicioctl(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 
240 static int iic_devsw_installed = 0;
241 
242 static void
243 iic_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 
254 CDEV_DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, CDEV_MAJOR,
255 			iic_cdevsw, 0, 0);
256 
257 SYSINIT(iicdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,iic_drvinit,NULL)
258