xref: /dragonfly/sys/bus/iicbus/iic.c (revision 956939d5)
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: src/sys/dev/iicbus/iic.c,v 1.18 1999/11/18 05:43:32 peter Exp $
27  * $DragonFly: src/sys/bus/iicbus/iic.c,v 1.10 2006/09/10 01:26:32 dillon Exp $
28  *
29  */
30 #include <sys/param.h>
31 #include <sys/kernel.h>
32 #include <sys/systm.h>
33 #include <sys/module.h>
34 #include <sys/bus.h>
35 #include <sys/conf.h>
36 #include <sys/buf.h>
37 #include <sys/uio.h>
38 #include <sys/malloc.h>
39 #include <sys/fcntl.h>
40 
41 #include <machine/clock.h>
42 
43 #include "iiconf.h"
44 #include "iicbus.h"
45 
46 #include <machine/iic.h>
47 
48 #include "iicbus_if.h"
49 
50 #define BUFSIZE 1024
51 
52 struct iic_softc {
53 
54 	u_char sc_addr;			/* address on iicbus */
55 	int sc_count;			/* >0 if device opened */
56 
57 	char sc_buffer[BUFSIZE];	/* output buffer */
58 	char sc_inbuf[BUFSIZE];		/* input buffer */
59 };
60 
61 #define IIC_SOFTC(unit) \
62 	((struct iic_softc *)devclass_get_softc(iic_devclass, (unit)))
63 
64 #define IIC_DEVICE(unit) \
65 	(devclass_get_device(iic_devclass, (unit)))
66 
67 static int iic_probe(device_t);
68 static int iic_attach(device_t);
69 
70 static devclass_t iic_devclass;
71 
72 static device_method_t iic_methods[] = {
73 	/* device interface */
74 	DEVMETHOD(device_probe,		iic_probe),
75 	DEVMETHOD(device_attach,	iic_attach),
76 
77 	/* iicbus interface */
78 	DEVMETHOD(iicbus_intr,		iicbus_generic_intr),
79 
80 	{ 0, 0 }
81 };
82 
83 static driver_t iic_driver = {
84 	"iic",
85 	iic_methods,
86 	sizeof(struct iic_softc),
87 };
88 
89 static	d_open_t	iicopen;
90 static	d_close_t	iicclose;
91 static	d_write_t	iicwrite;
92 static	d_read_t	iicread;
93 static	d_ioctl_t	iicioctl;
94 
95 #define CDEV_MAJOR 105
96 static struct dev_ops iic_ops = {
97 	{ "iic", CDEV_MAJOR, 0 },
98 	.d_open =	iicopen,
99 	.d_close =	iicclose,
100 	.d_read =	iicread,
101 	.d_write =	iicwrite,
102 	.d_ioctl =	iicioctl,
103 };
104 
105 /*
106  * iicprobe()
107  */
108 static int
109 iic_probe(device_t dev)
110 {
111 	struct iic_softc *sc = (struct iic_softc *)device_get_softc(dev);
112 
113 	sc->sc_addr = iicbus_get_addr(dev);
114 
115 	/* XXX detect chip with start/stop conditions */
116 
117 	return (0);
118 }
119 
120 /*
121  * iicattach()
122  */
123 static int
124 iic_attach(device_t dev)
125 {
126 	make_dev(&iic_ops, device_get_unit(dev),	/* XXX cleanup */
127 			UID_ROOT, GID_WHEEL,
128 			0600, "iic%d", device_get_unit(dev));
129 	return (0);
130 }
131 
132 static int
133 iicopen (struct dev_open_args *ap)
134 {
135 	cdev_t dev = ap->a_head.a_dev;
136 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
137 
138 	if (!sc)
139 		return (EINVAL);
140 
141 	if (sc->sc_count > 0)
142 		return (EBUSY);
143 
144 	sc->sc_count++;
145 
146 	return (0);
147 }
148 
149 static int
150 iicclose(struct dev_close_args *ap)
151 {
152 	cdev_t dev = ap->a_head.a_dev;
153 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
154 
155 	if (!sc)
156 		return (EINVAL);
157 
158 	if (!sc->sc_count)
159 		return (EINVAL);
160 
161 	sc->sc_count--;
162 
163 	if (sc->sc_count < 0)
164 		panic("%s: iic_count < 0!", __func__);
165 
166 	return (0);
167 }
168 
169 static int
170 iicwrite(struct dev_write_args *ap)
171 {
172 	cdev_t dev = ap->a_head.a_dev;
173 	struct uio *uio = ap->a_uio;
174 	device_t iicdev = IIC_DEVICE(minor(dev));
175 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
176 	int sent, error, count;
177 
178 	if (!sc || !iicdev)
179 		return (EINVAL);
180 
181 	if (sc->sc_count == 0)
182 		return (EINVAL);
183 
184 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
185 		return (error);
186 
187 	count = (int)szmin(uio->uio_resid, BUFSIZE);
188 	uiomove(sc->sc_buffer, (size_t)count, uio);
189 
190 	error = iicbus_block_write(device_get_parent(iicdev), sc->sc_addr,
191 					sc->sc_buffer, count, &sent);
192 
193 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
194 
195 	return(error);
196 }
197 
198 static int
199 iicread(struct dev_read_args *ap)
200 {
201 	cdev_t dev = ap->a_head.a_dev;
202 	struct uio *uio = ap->a_uio;
203 	device_t iicdev = IIC_DEVICE(minor(dev));
204 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
205 	int len, error = 0;
206 	int bufsize;
207 
208 	if (!sc || !iicdev)
209 		return (EINVAL);
210 
211 	if (sc->sc_count == 0)
212 		return (EINVAL);
213 
214 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev, IIC_DONTWAIT)))
215 		return (error);
216 
217 	/* max amount of data to read */
218 	len = (int)szmin(uio->uio_resid, BUFSIZE);
219 
220 	if ((error = iicbus_block_read(device_get_parent(iicdev), sc->sc_addr,
221 					sc->sc_inbuf, len, &bufsize)))
222 		return (error);
223 
224 	if (bufsize > uio->uio_resid)
225 		panic("%s: too much data read!", __func__);
226 
227 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
228 
229 	return (uiomove(sc->sc_inbuf, (size_t)bufsize, uio));
230 }
231 
232 static int
233 iicioctl(struct dev_ioctl_args *ap)
234 {
235 	cdev_t dev = ap->a_head.a_dev;
236 	device_t iicdev = IIC_DEVICE(minor(dev));
237 	struct iic_softc *sc = IIC_SOFTC(minor(dev));
238 	device_t parent = device_get_parent(iicdev);
239 	struct iiccmd *s = (struct iiccmd *)ap->a_data;
240 	int error, count;
241 
242 	if (!sc)
243 		return (EINVAL);
244 
245 	if ((error = iicbus_request_bus(device_get_parent(iicdev), iicdev,
246 			(ap->a_fflag & O_NONBLOCK) ? IIC_DONTWAIT :
247 						(IIC_WAIT | IIC_INTR))))
248 		return (error);
249 
250 	switch (ap->a_cmd) {
251 	case I2CSTART:
252 		error = iicbus_start(parent, s->slave, 0);
253 		break;
254 
255 	case I2CSTOP:
256 		error = iicbus_stop(parent);
257 		break;
258 
259 	case I2CRSTCARD:
260 		error = iicbus_reset(parent, 0, 0, NULL);
261 		break;
262 
263 	case I2CWRITE:
264 		error = iicbus_write(parent, s->buf, s->count, &count, 0);
265 		break;
266 
267 	case I2CREAD:
268 		error = iicbus_read(parent, s->buf, s->count, &count, s->last, 0);
269 		break;
270 
271 	default:
272 		error = ENODEV;
273 	}
274 
275 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
276 
277 	return (error);
278 }
279 
280 DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, 0, 0);
281