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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/systm.h>
33 #include <sys/malloc.h>
34 #include <sys/module.h>
35 #include <sys/mutex.h>
38 #include <dev/iicbus/iiconf.h>
39 #include <dev/iicbus/iicbus.h>
40 #include "iicbus_if.h"
43 * Translate IIC_Exxxxx status values to vaguely-equivelent errno values.
46 iic2errno(int iic_status)
49 case IIC_NOERR: return (0);
50 case IIC_EBUSERR: return (EALREADY);
51 case IIC_ENOACK: return (EIO);
52 case IIC_ETIMEOUT: return (ETIMEDOUT);
53 case IIC_EBUSBSY: return (EWOULDBLOCK);
54 case IIC_ESTATUS: return (EPROTO);
55 case IIC_EUNDERFLOW: return (EIO);
56 case IIC_EOVERFLOW: return (EOVERFLOW);
57 case IIC_ENOTSUPP: return (EOPNOTSUPP);
58 case IIC_ENOADDR: return (EADDRNOTAVAIL);
59 case IIC_ERESOURCE: return (ENOMEM);
60 default: return (EIO);
68 iicbus_intr(device_t bus, int event, char *buf)
70 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
72 /* call owner's intr routine */
74 IICBUS_INTR(sc->owner, event, buf);
80 iicbus_poll(struct iicbus_softc *sc, int how)
84 IICBUS_ASSERT_LOCKED(sc);
86 case IIC_WAIT | IIC_INTR:
87 error = mtx_sleep(sc, &sc->lock, IICPRI|PCATCH, "iicreq", 0);
90 case IIC_WAIT | IIC_NOINTR:
91 error = mtx_sleep(sc, &sc->lock, IICPRI, "iicreq", 0);
102 * iicbus_request_bus()
104 * Allocate the device to perform transfers.
106 * how : IIC_WAIT or IIC_DONTWAIT
109 iicbus_request_bus(device_t bus, device_t dev, int how)
111 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
116 while ((error == 0) && (sc->owner != NULL))
117 error = iicbus_poll(sc, how);
122 * Drop the lock around the call to the bus driver.
123 * This call should be allowed to sleep in the IIC_WAIT case.
124 * Drivers might also need to grab locks that would cause LOR
125 * if our lock is held.
128 /* Ask the underlying layers if the request is ok */
129 error = IICBUS_CALLBACK(device_get_parent(bus),
130 IIC_REQUEST_BUS, (caddr_t)&how);
146 * iicbus_release_bus()
148 * Release the device allocated with iicbus_request_dev()
151 iicbus_release_bus(device_t bus, device_t dev)
153 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
158 if (sc->owner != dev) {
160 return (IIC_EBUSBSY);
164 * Drop the lock around the call to the bus driver.
165 * This call should be allowed to sleep in the IIC_WAIT case.
166 * Drivers might also need to grab locks that would cause LOR
167 * if our lock is held.
170 /* Ask the underlying layers if the release is ok */
171 error = IICBUS_CALLBACK(device_get_parent(bus), IIC_RELEASE_BUS, NULL);
177 /* wakeup a waiting thread */
188 * Test if the iicbus is started by the controller
191 iicbus_started(device_t bus)
193 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
195 return (sc->started);
201 * Send start condition to the slave addressed by 'slave'
204 iicbus_start(device_t bus, u_char slave, int timeout)
206 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
210 return (IIC_ESTATUS); /* protocol error, bus already started */
212 if (!(error = IICBUS_START(device_get_parent(bus), slave, timeout)))
221 * iicbus_repeated_start()
223 * Send start condition to the slave addressed by 'slave'
226 iicbus_repeated_start(device_t bus, u_char slave, int timeout)
228 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
232 return (IIC_ESTATUS); /* protocol error, bus not started */
234 if (!(error = IICBUS_REPEATED_START(device_get_parent(bus), slave, timeout)))
245 * Send stop condition to the bus
248 iicbus_stop(device_t bus)
250 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
254 return (IIC_ESTATUS); /* protocol error, bus not started */
256 error = IICBUS_STOP(device_get_parent(bus));
258 /* refuse any further access */
267 * Write a block of data to the slave previously started by
268 * iicbus_start() call
271 iicbus_write(device_t bus, const char *buf, int len, int *sent, int timeout)
273 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
275 /* a slave must have been started for writing */
276 if (sc->started == 0 || (sc->strict != 0 && (sc->started & LSB) != 0))
277 return (IIC_ESTATUS);
279 return (IICBUS_WRITE(device_get_parent(bus), buf, len, sent, timeout));
285 * Read a block of data from the slave previously started by
289 iicbus_read(device_t bus, char *buf, int len, int *read, int last, int delay)
291 struct iicbus_softc *sc = (struct iicbus_softc *)device_get_softc(bus);
293 /* a slave must have been started for reading */
294 if (sc->started == 0 || (sc->strict != 0 && (sc->started & LSB) == 0))
295 return (IIC_ESTATUS);
297 return (IICBUS_READ(device_get_parent(bus), buf, len, read, last, delay));
301 * iicbus_write_byte()
303 * Write a byte to the slave previously started by iicbus_start() call
306 iicbus_write_byte(device_t bus, char byte, int timeout)
308 struct iicbus_softc *sc = device_get_softc(bus);
312 /* a slave must have been started for writing */
313 if (sc->started == 0 || (sc->strict != 0 && (sc->started & LSB) != 0))
314 return (IIC_ESTATUS);
316 return (iicbus_write(bus, &data, 1, &sent, timeout));
322 * Read a byte from the slave previously started by iicbus_start() call
325 iicbus_read_byte(device_t bus, char *byte, int timeout)
327 struct iicbus_softc *sc = device_get_softc(bus);
330 /* a slave must have been started for reading */
331 if (sc->started == 0 || (sc->strict != 0 && (sc->started & LSB) == 0))
332 return (IIC_ESTATUS);
334 return (iicbus_read(bus, byte, 1, &read, IIC_LAST_READ, timeout));
338 * iicbus_block_write()
340 * Write a block of data to slave ; start/stop protocol managed
343 iicbus_block_write(device_t bus, u_char slave, char *buf, int len, int *sent)
345 u_char addr = slave & ~LSB;
348 if ((error = iicbus_start(bus, addr, 0)))
351 error = iicbus_write(bus, buf, len, sent, 0);
359 * iicbus_block_read()
361 * Read a block of data from slave ; start/stop protocol managed
364 iicbus_block_read(device_t bus, u_char slave, char *buf, int len, int *read)
366 u_char addr = slave | LSB;
369 if ((error = iicbus_start(bus, addr, 0)))
372 error = iicbus_read(bus, buf, len, read, IIC_LAST_READ, 0);
382 * Do an aribtrary number of transfers on the iicbus. We pass these
383 * raw requests to the bridge driver. If the bridge driver supports
384 * them directly, then it manages all the details. If not, it can use
385 * the helper function iicbus_transfer_gen() which will do the
386 * transfers at a low level.
388 * Pointers passed in as part of iic_msg must be kernel pointers.
389 * Callers that have user addresses to manage must do so on their own.
392 iicbus_transfer(device_t bus, struct iic_msg *msgs, uint32_t nmsgs)
395 return (IICBUS_TRANSFER(device_get_parent(bus), msgs, nmsgs));
399 iicbus_transfer_excl(device_t dev, struct iic_msg *msgs, uint32_t nmsgs,
405 bus = device_get_parent(dev);
406 error = iicbus_request_bus(bus, dev, how);
408 error = IICBUS_TRANSFER(bus, msgs, nmsgs);
409 iicbus_release_bus(bus, dev);
414 * Generic version of iicbus_transfer that calls the appropriate
415 * routines to accomplish this. See note above about acceptable
419 iicbus_transfer_gen(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
421 int i, error, lenread, lenwrote, nkid, rpstart, addr;
422 device_t *children, bus;
425 if ((error = device_get_children(dev, &children, &nkid)) != 0)
426 return (IIC_ERESOURCE);
428 free(children, M_TEMP);
429 return (IIC_ENOTSUPP);
433 free(children, M_TEMP);
434 nostop = iicbus_get_nostop(dev);
435 for (i = 0, error = 0; i < nmsgs && error == 0; i++) {
436 addr = msgs[i].slave;
437 if (msgs[i].flags & IIC_M_RD)
442 if (!(msgs[i].flags & IIC_M_NOSTART)) {
444 error = iicbus_repeated_start(bus, addr, 0);
446 error = iicbus_start(bus, addr, 0);
451 if (msgs[i].flags & IIC_M_RD)
452 error = iicbus_read(bus, msgs[i].buf, msgs[i].len,
453 &lenread, IIC_LAST_READ, 0);
455 error = iicbus_write(bus, msgs[i].buf, msgs[i].len,
460 if ((msgs[i].flags & IIC_M_NOSTOP) != 0 ||
461 (nostop && i + 1 < nmsgs)) {
462 rpstart = 1; /* Next message gets repeated start */
468 if (error != 0 && !nostop)