xref: /freebsd/sys/dev/iicbus/iic.c (revision 6e8394b8baa7d5d9153ab90de6824bcd19b3b4e1)
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 1.11 1999/05/30 16:51:28 phk 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 
51 struct 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 
66 static int iic_probe(device_t);
67 static int iic_attach(device_t);
68 
69 static devclass_t iic_devclass;
70 
71 static 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 
82 static driver_t iic_driver = {
83 	"iic",
84 	iic_methods,
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 	/* open */	iicopen,
97 	/* close */	iicclose,
98 	/* read */	iicread,
99 	/* write */	iicwrite,
100 	/* ioctl */	iicioctl,
101 	/* stop */	nostop,
102 	/* reset */	noreset,
103 	/* devtotty */	nodevtotty,
104 	/* poll */	nopoll,
105 	/* mmap */	nommap,
106 	/* strategy */	nostrategy,
107 	/* name */	"iic",
108 	/* parms */	noparms,
109 	/* maj */	CDEV_MAJOR,
110 	/* dump */	nodump,
111 	/* psize */	nopsize,
112 	/* flags */	0,
113 	/* maxio */	0,
114 	/* bmaj */	-1
115 };
116 
117 /*
118  * iicprobe()
119  */
120 static int
121 iic_probe(device_t dev)
122 {
123 	struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
124 	static int once;
125 
126 	if (!once++)
127                 cdevsw_add(&iic_cdevsw);
128 
129 	sc->sc_addr = iicbus_get_addr(dev);
130 
131 	/* XXX detect chip with start/stop conditions */
132 
133 	return (0);
134 }
135 
136 /*
137  * iicattach()
138  */
139 static int
140 iic_attach(device_t dev)
141 {
142 	return (0);
143 }
144 
145 static int
146 iicopen (dev_t dev, int flags, int fmt, struct proc *p)
147 {
148 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
149 
150 	if (!sc)
151 		return (EINVAL);
152 
153 	if (sc->sc_count > 0)
154 		return (EBUSY);
155 
156 	sc->sc_count++;
157 
158 	return (0);
159 }
160 
161 static int
162 iicclose(dev_t dev, int flags, int fmt, struct proc *p)
163 {
164 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
165 
166 	if (!sc)
167 		return (EINVAL);
168 
169 	if (!sc->sc_count)
170 		return (EINVAL);
171 
172 	sc->sc_count--;
173 
174 	if (sc->sc_count < 0)
175 		panic("%s: iic_count < 0!", __FUNCTION__);
176 
177 	return (0);
178 }
179 
180 static int
181 iicwrite(dev_t dev, struct uio * uio, int ioflag)
182 {
183 	device_t iicdev = IIC_DEVICE(minor(dev));
184 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
185 	int sent, error, count;
186 
187 	if (!sc || !iicdev)
188 		return (EINVAL);
189 
190 	if (sc->sc_count == 0)
191 		return (EINVAL);
192 
193 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
194 		return (error);
195 
196 	count = min(uio->uio_resid, BUFSIZE);
197 	uiomove(sc->sc_buffer, count, uio);
198 
199 	error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr,
200 					sc->sc_buffer, count, &sent);
201 
202 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
203 
204 	return(error);
205 }
206 
207 static int
208 iicread(dev_t dev, struct uio * uio, int ioflag)
209 {
210 	device_t iicdev = IIC_DEVICE(minor(dev));
211 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
212 	int len, error = 0;
213 	int bufsize;
214 
215 	if (!sc || !iicdev)
216 		return (EINVAL);
217 
218 	if (sc->sc_count == 0)
219 		return (EINVAL);
220 
221 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
222 		return (error);
223 
224 	/* max amount of data to read */
225 	len = min(uio->uio_resid, BUFSIZE);
226 
227 	if ((error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr,
228 					sc->sc_inbuf, len, &bufsize)))
229 		return (error);
230 
231 	if (bufsize > uio->uio_resid)
232 		panic("%s: too much data read!", __FUNCTION__);
233 
234 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
235 
236 	return (uiomove(sc->sc_inbuf, bufsize, uio));
237 }
238 
239 static int
240 iicioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
241 {
242 	device_t iicdev = IIC_DEVICE(minor(dev));
243 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
244 	device_t parent = device_get_parent(iicdev);
245 	struct iiccmd *s = (struct iiccmd *)data;
246 	int error, count;
247 
248 	if (!sc)
249 		return (EINVAL);
250 
251 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev,
252 			(flags & O_NONBLOCK) ? IIC_DONTWAIT :
253 						(IIC_WAIT | IIC_INTR))))
254 		return (error);
255 
256 	switch (cmd) {
257 	case I2CSTART:
258 		error = iicbus_start(parent, s->slave, 0);
259 		break;
260 
261 	case I2CSTOP:
262 		error = iicbus_stop(parent);
263 		break;
264 
265 	case I2CRSTCARD:
266 		error = iicbus_reset(parent, 0, 0, NULL);
267 		break;
268 
269 	case I2CWRITE:
270 		error = iicbus_write(parent, s->buf, s->count, &count, 0);
271 		break;
272 
273 	case I2CREAD:
274 		error = iicbus_read(parent, s->buf, s->count, &count, s->last, 0);
275 		break;
276 
277 	default:
278 		error = ENODEV;
279 	}
280 
281 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
282 
283 	return (error);
284 }
285 
286 DEV_DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, CDEV_MAJOR,
287 			NOMAJ, iic_cdevsw, 0, 0);
288