xref: /freebsd/sys/dev/iicbus/iic.c (revision 56ca39961bd1c9946a505c41c3fc634ef63fdd42)
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  * $FreeBSD$
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/uio.h>
36 #include <sys/fcntl.h>
37 
38 #include <machine/clock.h>
39 
40 #include <dev/iicbus/iiconf.h>
41 #include <dev/iicbus/iicbus.h>
42 
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 	sizeof(struct iic_softc),
84 };
85 
86 static	d_open_t	iicopen;
87 static	d_close_t	iicclose;
88 static	d_write_t	iicwrite;
89 static	d_read_t	iicread;
90 static	d_ioctl_t	iicioctl;
91 
92 #define CDEV_MAJOR 105
93 static struct cdevsw iic_cdevsw = {
94 	/* open */	iicopen,
95 	/* close */	iicclose,
96 	/* read */	iicread,
97 	/* write */	iicwrite,
98 	/* ioctl */	iicioctl,
99 	/* poll */	nopoll,
100 	/* mmap */	nommap,
101 	/* strategy */	nostrategy,
102 	/* name */	"iic",
103 	/* maj */	CDEV_MAJOR,
104 	/* dump */	nodump,
105 	/* psize */	nopsize,
106 	/* flags */	0,
107 	/* bmaj */	-1
108 };
109 
110 /*
111  * iicprobe()
112  */
113 static int
114 iic_probe(device_t dev)
115 {
116 	struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
117 
118 	sc->sc_addr = iicbus_get_addr(dev);
119 
120 	/* XXX detect chip with start/stop conditions */
121 
122 	return (0);
123 }
124 
125 /*
126  * iicattach()
127  */
128 static int
129 iic_attach(device_t dev)
130 {
131 	make_dev(&iic_cdevsw, device_get_unit(dev),	/* XXX cleanup */
132 			UID_ROOT, GID_WHEEL,
133 			0600, "iic%d", device_get_unit(dev));
134 	return (0);
135 }
136 
137 static int
138 iicopen (dev_t dev, int flags, int fmt, struct proc *p)
139 {
140 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
141 
142 	if (!sc)
143 		return (EINVAL);
144 
145 	if (sc->sc_count > 0)
146 		return (EBUSY);
147 
148 	sc->sc_count++;
149 
150 	return (0);
151 }
152 
153 static int
154 iicclose(dev_t dev, int flags, int fmt, struct proc *p)
155 {
156 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
157 
158 	if (!sc)
159 		return (EINVAL);
160 
161 	if (!sc->sc_count)
162 		return (EINVAL);
163 
164 	sc->sc_count--;
165 
166 	if (sc->sc_count < 0)
167 		panic("%s: iic_count < 0!", __FUNCTION__);
168 
169 	return (0);
170 }
171 
172 static int
173 iicwrite(dev_t dev, struct uio * uio, int ioflag)
174 {
175 	device_t iicdev = IIC_DEVICE(minor(dev));
176 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
177 	int sent, error, count;
178 
179 	if (!sc || !iicdev)
180 		return (EINVAL);
181 
182 	if (sc->sc_count == 0)
183 		return (EINVAL);
184 
185 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
186 		return (error);
187 
188 	count = min(uio->uio_resid, BUFSIZE);
189 	uiomove(sc->sc_buffer, count, uio);
190 
191 	error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr,
192 					sc->sc_buffer, count, &sent);
193 
194 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
195 
196 	return(error);
197 }
198 
199 static int
200 iicread(dev_t dev, struct uio * uio, int ioflag)
201 {
202 	device_t iicdev = IIC_DEVICE(minor(dev));
203 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
204 	int len, error = 0;
205 	int bufsize;
206 
207 	if (!sc || !iicdev)
208 		return (EINVAL);
209 
210 	if (sc->sc_count == 0)
211 		return (EINVAL);
212 
213 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
214 		return (error);
215 
216 	/* max amount of data to read */
217 	len = min(uio->uio_resid, BUFSIZE);
218 
219 	if ((error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr,
220 					sc->sc_inbuf, len, &bufsize)))
221 		return (error);
222 
223 	if (bufsize > uio->uio_resid)
224 		panic("%s: too much data read!", __FUNCTION__);
225 
226 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
227 
228 	return (uiomove(sc->sc_inbuf, bufsize, uio));
229 }
230 
231 static int
232 iicioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
233 {
234 	device_t iicdev = IIC_DEVICE(minor(dev));
235 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
236 	device_t parent = device_get_parent(iicdev);
237 	struct iiccmd *s = (struct iiccmd *)data;
238 	int error, count;
239 
240 	if (!sc)
241 		return (EINVAL);
242 
243 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev,
244 			(flags & O_NONBLOCK) ? IIC_DONTWAIT :
245 						(IIC_WAIT | IIC_INTR))))
246 		return (error);
247 
248 	switch (cmd) {
249 	case I2CSTART:
250 		error = iicbus_start(parent, s->slave, 0);
251 		break;
252 
253 	case I2CSTOP:
254 		error = iicbus_stop(parent);
255 		break;
256 
257 	case I2CRSTCARD:
258 		error = iicbus_reset(parent, 0, 0, NULL);
259 		break;
260 
261 	case I2CWRITE:
262 		error = iicbus_write(parent, s->buf, s->count, &count, 0);
263 		break;
264 
265 	case I2CREAD:
266 		error = iicbus_read(parent, s->buf, s->count, &count, s->last, 0);
267 		break;
268 
269 	default:
270 		error = ENODEV;
271 	}
272 
273 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
274 
275 	return (error);
276 }
277 
278 DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, 0, 0);
279