2 * Copyright (c) 1998 Nicolas Souchu
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
26 * $FreeBSD: src/sys/dev/iicbus/iiconf.c,v 1.10 1999/12/03 08:41:02 mdodd Exp $
27 * $DragonFly: src/sys/bus/iicbus/iiconf.c,v 1.5 2005/06/02 20:40:36 dillon Exp $
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 #include <sys/module.h>
36 #include <sys/thread2.h>
40 #include "iicbus_if.h"
46 iicbus_intr(device_t bus, int event, char *buf)
48 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
50 /* call owner's intr routine */
52 IICBUS_INTR(sc->owner, event, buf);
60 * Allocate a new bus connected to the given parent device
63 iicbus_alloc_bus(device_t parent)
67 /* add the bus to the parent */
68 child = device_add_child(parent, "iicbus", -1);
74 iicbus_poll(struct iicbus_softc *sc, int how)
79 case (IIC_WAIT | IIC_INTR):
80 error = tsleep(sc, PCATCH, "iicreq", 0);
83 case (IIC_WAIT | IIC_NOINTR):
84 error = tsleep(sc, 0, "iicreq", 0);
96 * iicbus_request_bus()
98 * Allocate the device to perform transfers.
100 * how : IIC_WAIT or IIC_DONTWAIT
103 iicbus_request_bus(device_t bus, device_t dev, int how)
105 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
108 /* first, ask the underlying layers if the request is ok */
110 error = IICBUS_CALLBACK(device_get_parent(bus),
111 IIC_REQUEST_BUS, (caddr_t)&how);
113 error = iicbus_poll(sc, how);
114 } while (error == EWOULDBLOCK);
118 if (sc->owner && sc->owner != dev) {
120 error = iicbus_poll(sc, how);
127 /* free any allocated resource */
129 IICBUS_CALLBACK(device_get_parent(bus), IIC_RELEASE_BUS,
137 * iicbus_release_bus()
139 * Release the device allocated with iicbus_request_dev()
142 iicbus_release_bus(device_t bus, device_t dev)
144 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
147 /* first, ask the underlying layers if the release is ok */
148 error = IICBUS_CALLBACK(device_get_parent(bus), IIC_RELEASE_BUS, NULL);
154 if (sc->owner != dev) {
161 /* wakeup waiting processes */
170 * Test if the iicbus is started by the controller
173 iicbus_started(device_t bus)
175 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
177 return (sc->started);
183 * Send start condition to the slave addressed by 'slave'
186 iicbus_start(device_t bus, u_char slave, int timeout)
188 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
192 return (EINVAL); /* bus already started */
194 if (!(error = IICBUS_START(device_get_parent(bus), slave, timeout)))
203 * iicbus_repeated_start()
205 * Send start condition to the slave addressed by 'slave'
208 iicbus_repeated_start(device_t bus, u_char slave, int timeout)
210 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
214 return (EINVAL); /* bus should have been already started */
216 if (!(error = IICBUS_REPEATED_START(device_get_parent(bus), slave, timeout)))
227 * Send stop condition to the bus
230 iicbus_stop(device_t bus)
232 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
236 return (EINVAL); /* bus not started */
238 error = IICBUS_STOP(device_get_parent(bus));
240 /* refuse any further access */
249 * Write a block of data to the slave previously started by
250 * iicbus_start() call
253 iicbus_write(device_t bus, const char *buf, int len, int *sent, int timeout)
255 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
257 /* a slave must have been started with the appropriate address */
258 if (!sc->started || (sc->started & LSB))
261 return (IICBUS_WRITE(device_get_parent(bus), buf, len, sent, timeout));
267 * Read a block of data from the slave previously started by
271 iicbus_read(device_t bus, char *buf, int len, int *read, int last, int delay)
273 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
275 /* a slave must have been started with the appropriate address */
276 if (!sc->started || !(sc->started & LSB))
279 return (IICBUS_READ(device_get_parent(bus), buf, len, read, last, delay));
283 * iicbus_write_byte()
285 * Write a byte to the slave previously started by iicbus_start() call
288 iicbus_write_byte(device_t bus, char byte, int timeout)
293 return (iicbus_write(bus, &data, 1, &sent, timeout));
299 * Read a byte from the slave previously started by iicbus_start() call
302 iicbus_read_byte(device_t bus, char *byte, int timeout)
306 return (iicbus_read(bus, byte, 1, &read, IIC_LAST_READ, timeout));
310 * iicbus_block_write()
312 * Write a block of data to slave ; start/stop protocol managed
315 iicbus_block_write(device_t bus, u_char slave, char *buf, int len, int *sent)
317 u_char addr = slave & ~LSB;
320 if ((error = iicbus_start(bus, addr, 0)))
323 error = iicbus_write(bus, buf, len, sent, 0);
331 * iicbus_block_read()
333 * Read a block of data from slave ; start/stop protocol managed
336 iicbus_block_read(device_t bus, u_char slave, char *buf, int len, int *read)
338 u_char addr = slave | LSB;
341 if ((error = iicbus_start(bus, addr, 0)))
344 error = iicbus_read(bus, buf, len, read, IIC_LAST_READ, 0);
354 * Get the I2C 7 bits address of the device
357 iicbus_get_addr(device_t dev)
360 device_t parent = device_get_parent(dev);
362 BUS_READ_IVAR(parent, dev, IICBUS_IVAR_ADDR, &addr);
364 return ((u_char)addr);