1/*-
2 * Copyright (c) 1998 Nicolas Souchu, Marc Bouget
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: head/sys/dev/pcf/pcf.c 93165 2002-03-25 21:22:35Z nsouch $
27 *
28 */
29#include <sys/param.h>
30#include <sys/systm.h>
31#include <sys/kernel.h>
32#include <sys/module.h>
33#include <sys/bus.h>
34
35#include <machine/bus.h>
36#include <machine/resource.h>
37#include <sys/rman.h>
38
39#include <isa/isareg.h>
40#include <isa/isavar.h>
41
42#include <i386/isa/isa_device.h>
43
44#include <dev/iicbus/iiconf.h>
45#include "iicbus_if.h"
46
47#define IO_PCFSIZE 2
48
49#define TIMEOUT 9999 /* XXX */
50
51/* Status bits of S1 register (read only) */
52#define nBB 0x01 /* busy when low set/reset by STOP/START*/
53#define LAB 0x02 /* lost arbitration bit in multi-master mode */
54#define AAS 0x04 /* addressed as slave */
55#define LRB 0x08 /* last received byte when not AAS */
56#define AD0 0x08 /* general call received when AAS */
57#define BER 0x10 /* bus error, misplaced START or STOP */
58#define STS 0x20 /* STOP detected in slave receiver mode */
59#define PIN 0x80 /* pending interrupt not (r/w) */
60
61/* Control bits of S1 register (write only) */
62#define ACK 0x01
63#define STO 0x02
64#define STA 0x04
65#define ENI 0x08
66#define ES2 0x10
67#define ES1 0x20
68#define ES0 0x40
69
70#define BUFSIZE 2048
71
72#define SLAVE_TRANSMITTER 0x1
73#define SLAVE_RECEIVER 0x2
74
75#define PCF_DEFAULT_ADDR 0xaa
76
77struct pcf_softc {
78
79 int pcf_base; /* isa port */
80 int pcf_flags;
81 u_char pcf_addr; /* interface I2C address */
82
83 int pcf_slave_mode; /* receiver or transmitter */
84 int pcf_started; /* 1 if start condition sent */
85
86 device_t iicbus; /* the corresponding iicbus */
87
88 int rid_irq, rid_ioport;
89 struct resource *res_irq, *res_ioport;
90 void *intr_cookie;
91};
92
93static int pcf_probe(device_t);
94static int pcf_attach(device_t);
95static void pcfintr(void *arg);
96
97static int pcf_print_child(device_t, device_t);
98
99static int pcf_repeated_start(device_t, u_char, int);
100static int pcf_start(device_t, u_char, int);
101static int pcf_stop(device_t);
102static int pcf_write(device_t, char *, int, int *, int);
103static int pcf_read(device_t, char *, int, int *, int, int);
104static int pcf_rst_card(device_t, u_char, u_char, u_char *);
105
106static device_method_t pcf_methods[] = {
107 /* device interface */
108 DEVMETHOD(device_probe, pcf_probe),
109 DEVMETHOD(device_attach, pcf_attach),
110
111 /* bus interface */
112 DEVMETHOD(bus_print_child, pcf_print_child),
113
114 /* iicbus interface */
115 DEVMETHOD(iicbus_callback, iicbus_null_callback),
116 DEVMETHOD(iicbus_repeated_start, pcf_repeated_start),
117 DEVMETHOD(iicbus_start, pcf_start),
118 DEVMETHOD(iicbus_stop, pcf_stop),
119 DEVMETHOD(iicbus_write, pcf_write),
120 DEVMETHOD(iicbus_read, pcf_read),
121 DEVMETHOD(iicbus_reset, pcf_rst_card),
122
123 { 0, 0 }
124};
125
126static driver_t pcf_driver = {
127 "pcf",
128 pcf_methods,
129 sizeof(struct pcf_softc),
130};
131
132static devclass_t pcf_devclass;
133
134#define DEVTOSOFTC(dev) ((struct pcf_softc *)device_get_softc(dev))
135
136static int
137pcf_probe(device_t pcfdev)
138{
139 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
140 device_t parent = device_get_parent(pcfdev);
141
142 device_set_desc(pcfdev, "PCF8584 I2C bus controller");
143
144 pcf = DEVTOSOFTC(pcfdev);
145 bzero(pcf, sizeof(struct pcf_softc));
146
147 pcf->rid_irq = pcf->rid_ioport = 0;
148 pcf->res_irq = pcf->res_ioport = 0;
149
150 /* IO port is mandatory */
151 pcf->res_ioport = bus_alloc_resource(pcfdev, SYS_RES_IOPORT,
152 &pcf->rid_ioport, 0ul, ~0ul,
153 IO_PCFSIZE, RF_ACTIVE);
154 if (pcf->res_ioport == 0) {
155 device_printf(pcfdev, "cannot reserve I/O port range\n");
156 goto error;
157 }
158 BUS_READ_IVAR(parent, pcfdev, ISA_IVAR_PORT, &pcf->pcf_base);
159
160 pcf->pcf_flags = device_get_flags(pcfdev);
161
162 if (!(pcf->pcf_flags & IIC_POLLED)) {
163 pcf->res_irq = bus_alloc_resource(pcfdev, SYS_RES_IRQ, &pcf->rid_irq,
164 0ul, ~0ul, 1, RF_ACTIVE);
165 if (pcf->res_irq == 0) {
166 device_printf(pcfdev, "can't reserve irq, polled mode.\n");
167 pcf->pcf_flags |= IIC_POLLED;
168 }
169 }
170
171 /* reset the chip */
172 pcf_rst_card(pcfdev, IIC_FASTEST, PCF_DEFAULT_ADDR, NULL);
173
174 return (0);
175error:
176 if (pcf->res_ioport != 0) {
177 bus_deactivate_resource(pcfdev, SYS_RES_IOPORT, pcf->rid_ioport,
178 pcf->res_ioport);
179 bus_release_resource(pcfdev, SYS_RES_IOPORT, pcf->rid_ioport,
180 pcf->res_ioport);
181 }
182 return (ENXIO);
183}
184
185static int
186pcf_attach(device_t pcfdev)
187{
188 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
189 device_t parent = device_get_parent(pcfdev);
190 int error = 0;
191
192 if (pcf->res_irq) {
193 /* default to the tty mask for registration */ /* XXX */
194 error = BUS_SETUP_INTR(parent, pcfdev, pcf->res_irq, INTR_TYPE_NET,
195 pcfintr, pcfdev, &pcf->intr_cookie);
196 if (error)
197 return (error);
198 }
199
200 pcf->iicbus = device_add_child(pcfdev, "iicbus", -1);
201
202 /* probe and attach the iicbus */
203 bus_generic_attach(pcfdev);
204
205 return (0);
206}
207
208static int
209pcf_print_child(device_t bus, device_t dev)
210{
211 struct pcf_softc *pcf = (struct pcf_softc *)device_get_softc(bus);
212 int retval = 0;
213
214 retval += bus_print_child_header(bus, dev);
215 retval += printf(" on %s addr 0x%x\n", device_get_nameunit(bus),
216 (int)pcf->pcf_addr);
217
218 return (retval);
219}
220
221/*
222 * PCF8584 datasheet : when operate at 8 MHz or more, a minimun time of
223 * 6 clocks cycles must be left between two consecutives access
224 */
225#define pcf_nops() DELAY(10)
226
227#define dummy_read(pcf) PCF_GET_S0(pcf)
228#define dummy_write(pcf) PCF_SET_S0(pcf, 0)
229
230/*
231 * Specific register access to PCF8584
232 */
233static void PCF_SET_S0(struct pcf_softc *pcf, int data)
234{
235 outb(pcf->pcf_base, data);
236 pcf_nops();
237}
238
239static void PCF_SET_S1(struct pcf_softc *pcf, int data)
240{
241 outb(pcf->pcf_base+1, data);
242 pcf_nops();
243}
244
245static char PCF_GET_S0(struct pcf_softc *pcf)
246{
247 char data;
248
249 data = inb(pcf->pcf_base);
250 pcf_nops();
251
252 return (data);
253}
254
255static char PCF_GET_S1(struct pcf_softc *pcf)
256{
257 char data;
258
259 data = inb(pcf->pcf_base+1);
260 pcf_nops();
261
262 return (data);
263}
264
265/*
266 * Polling mode for master operations wait for a new
267 * byte incomming or outgoing
268 */
269static int pcf_wait_byte(struct pcf_softc *pcf)
270{
271 int counter = TIMEOUT;
272
273 while (counter--) {
274
275 if ((PCF_GET_S1(pcf) & PIN) == 0)
276 return (0);
277 }
278
279 return (IIC_ETIMEOUT);
280}
281
282static int pcf_stop(device_t pcfdev)
283{
284 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
285
286 /*
287 * Send STOP condition iff the START condition was previously sent.
288 * STOP is sent only once even if a iicbus_stop() is called after
289 * an iicbus_read()... see pcf_read(): the pcf needs to send the stop
290 * before the last char is read.
291 */
292 if (pcf->pcf_started) {
293 /* set stop condition and enable IT */
294 PCF_SET_S1(pcf, PIN|ES0|ENI|STO|ACK);
295
296 pcf->pcf_started = 0;
297 }
298
299 return (0);
300}
301
302
303static int pcf_noack(struct pcf_softc *pcf, int timeout)
304{
305 int noack;
306 int k = timeout/10;
307
308 do {
309 noack = PCF_GET_S1(pcf) & LRB;
310 if (!noack)
311 break;
312 DELAY(10); /* XXX wait 10 us */
313 } while (k--);
314
315 return (noack);
316}
317
318static int pcf_repeated_start(device_t pcfdev, u_char slave, int timeout)
319{
320 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
321 int error = 0;
322
323 /* repeated start */
324 PCF_SET_S1(pcf, ES0|STA|STO|ACK);
325
326 /* set slave address to PCF. Last bit (LSB) must be set correctly
327 * according to transfer direction */
328 PCF_SET_S0(pcf, slave);
329
330 /* wait for address sent, polling */
331 if ((error = pcf_wait_byte(pcf)))
332 goto error;
333
334 /* check for ack */
335 if (pcf_noack(pcf, timeout)) {
336 error = IIC_ENOACK;
337 goto error;
338 }
339
340 return (0);
341
342error:
343 pcf_stop(pcfdev);
344 return (error);
345}
346
347static int pcf_start(device_t pcfdev, u_char slave, int timeout)
348{
349 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
350 int error = 0;
351
352 if ((PCF_GET_S1(pcf) & nBB) == 0)
353 return (IIC_EBUSBSY);
354
355 /* set slave address to PCF. Last bit (LSB) must be set correctly
356 * according to transfer direction */
357 PCF_SET_S0(pcf, slave);
358
359 /* START only */
360 PCF_SET_S1(pcf, PIN|ES0|STA|ACK);
361
362 pcf->pcf_started = 1;
363
364 /* wait for address sent, polling */
365 if ((error = pcf_wait_byte(pcf)))
366 goto error;
367
368 /* check for ACK */
369 if (pcf_noack(pcf, timeout)) {
370 error = IIC_ENOACK;
371 goto error;
372 }
373
374 return (0);
375
376error:
377 pcf_stop(pcfdev);
378 return (error);
379}
380
381static void
382pcfintr(void *arg)
383{
384 device_t pcfdev = (device_t)arg;
385 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
386
387 char data, status, addr;
388 char error = 0;
389
390 status = PCF_GET_S1(pcf);
391
392 if (status & PIN) {
393 device_printf(pcfdev, "spurious interrupt, status=0x%x\n", status & 0xff);
394
395 goto error;
396 }
397
398 if (status & LAB)
399 device_printf(pcfdev, "bus arbitration lost!\n");
400
401 if (status & BER) {
402 error = IIC_EBUSERR;
403 iicbus_intr(pcf->iicbus, INTR_ERROR, &error);
404
405 goto error;
406 }
407
408 do {
409 status = PCF_GET_S1(pcf);
410
411 switch(pcf->pcf_slave_mode) {
412
413 case SLAVE_TRANSMITTER:
414 if (status & LRB) {
415 /* ack interrupt line */
416 dummy_write(pcf);
417
418 /* no ack, don't send anymore */
419 pcf->pcf_slave_mode = SLAVE_RECEIVER;
420
421 iicbus_intr(pcf->iicbus, INTR_NOACK, NULL);
422 break;
423 }
424
425 /* get data from upper code */
426 iicbus_intr(pcf->iicbus, INTR_TRANSMIT, &data);
427
428 PCF_SET_S0(pcf, data);
429 break;
430
431 case SLAVE_RECEIVER:
432 if (status & AAS) {
433 addr = PCF_GET_S0(pcf);
434
435 if (status & AD0)
436 iicbus_intr(pcf->iicbus, INTR_GENERAL, &addr);
437 else
438 iicbus_intr(pcf->iicbus, INTR_START, &addr);
439
440 if (addr & LSB) {
441 pcf->pcf_slave_mode = SLAVE_TRANSMITTER;
442
443 /* get the first char from upper code */
444 iicbus_intr(pcf->iicbus, INTR_TRANSMIT, &data);
445
446 /* send first data byte */
447 PCF_SET_S0(pcf, data);
448 }
449
450 break;
451 }
452
453 /* stop condition received? */
454 if (status & STS) {
455 /* ack interrupt line */
456 dummy_read(pcf);
457
458 /* emulate intr stop condition */
459 iicbus_intr(pcf->iicbus, INTR_STOP, NULL);
460
461 } else {
462 /* get data, ack interrupt line */
463 data = PCF_GET_S0(pcf);
464
465 /* deliver the character */
466 iicbus_intr(pcf->iicbus, INTR_RECEIVE, &data);
467 }
468 break;
469
470 default:
471 panic("%s: unknown slave mode (%d)!", __func__,
472 pcf->pcf_slave_mode);
473 }
474
475 } while ((PCF_GET_S1(pcf) & PIN) == 0);
476
477 return;
478
479error:
480 /* unknown event on bus...reset PCF */
481 PCF_SET_S1(pcf, PIN|ES0|ENI|ACK);
482
483 pcf->pcf_slave_mode = SLAVE_RECEIVER;
484
485 return;
486}
487
488static int pcf_rst_card(device_t pcfdev, u_char speed, u_char addr, u_char *oldaddr)
489{
490 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
491
492 if (oldaddr)
493 *oldaddr = pcf->pcf_addr;
494
495 /* retrieve own address from bus level */
496 if (!addr)
497 pcf->pcf_addr = PCF_DEFAULT_ADDR;
498 else
499 pcf->pcf_addr = addr;
500
501 PCF_SET_S1(pcf, PIN); /* initialize S1 */
502
503 /* own address S'O<>0 */
504 PCF_SET_S0(pcf, pcf->pcf_addr >> 1);
505
506 /* select clock register */
507 PCF_SET_S1(pcf, PIN|ES1);
508
509 /* select bus speed : 18=90kb, 19=45kb, 1A=11kb, 1B=1.5kb */
510 switch (speed) {
511 case IIC_SLOW:
512 PCF_SET_S0(pcf, 0x1b);
513 break;
514
515 case IIC_FAST:
516 PCF_SET_S0(pcf, 0x19);
517 break;
518
519 case IIC_UNKNOWN:
520 case IIC_FASTEST:
521 default:
522 PCF_SET_S0(pcf, 0x18);
523 break;
524 }
525
526 /* set bus on, ack=yes, INT=yes */
527 PCF_SET_S1(pcf, PIN|ES0|ENI|ACK);
528
529 pcf->pcf_slave_mode = SLAVE_RECEIVER;
530
531 return (0);
532}
533
534static int
535pcf_write(device_t pcfdev, char *buf, int len, int *sent, int timeout /* us */)
536{
537 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
538 int bytes, error = 0;
539
540#ifdef PCFDEBUG
541 printf("pcf%d: >> writing %d bytes\n", device_get_unit(pcfdev), len);
542#endif
543
544 bytes = 0;
545 while (len) {
546
547 PCF_SET_S0(pcf, *buf++);
548
549 /* wait for the byte to be send */
550 if ((error = pcf_wait_byte(pcf)))
551 goto error;
552
553 /* check if ack received */
554 if (pcf_noack(pcf, timeout)) {
555 error = IIC_ENOACK;
556 goto error;
557 }
558
559 len --;
560 bytes ++;
561 }
562
563error:
564 *sent = bytes;
565
566#ifdef PCFDEBUG
567 printf("pcf%d: >> %d bytes written (%d)\n",
568 device_get_unit(pcfdev), bytes, error);
569#endif
570
571 return (error);
572}
573
574static int
575pcf_read(device_t pcfdev, char *buf, int len, int *read, int last,
576 int delay /* us */)
577{
578 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
579 int bytes, error = 0;
580
581#ifdef PCFDEBUG
582 printf("pcf%d: << reading %d bytes\n", device_get_unit(pcfdev), len);
583#endif
584
585 /* trig the bus to get the first data byte in S0 */
586 if (len) {
587 if (len == 1 && last)
588 /* just one byte to read */
589 PCF_SET_S1(pcf, ES0); /* no ack */
590
591 dummy_read(pcf);
592 }
593
594 bytes = 0;
595 while (len) {
596
597 /* XXX delay needed here */
598
599 /* wait for trigged byte */
600 if ((error = pcf_wait_byte(pcf))) {
601 pcf_stop(pcfdev);
602 goto error;
603 }
604
605 if (len == 1 && last)
606 /* ok, last data byte already in S0, no I2C activity
607 * on next PCF_GET_S0() */
608 pcf_stop(pcfdev);
609
610 else if (len == 2 && last)
611 /* next trigged byte with no ack */
612 PCF_SET_S1(pcf, ES0);
613
614 /* receive byte, trig next byte */
615 *buf++ = PCF_GET_S0(pcf);
616
617 len --;
618 bytes ++;
619 };
620
621error:
622 *read = bytes;
623
624#ifdef PCFDEBUG
625 printf("pcf%d: << %d bytes read (%d)\n",
626 device_get_unit(pcfdev), bytes, error);
627#endif
628
629 return (error);
630}
631
632DRIVER_MODULE(pcf, isa, pcf_driver, pcf_devclass, 0, 0);
2 * Copyright (c) 1998 Nicolas Souchu, Marc Bouget
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: head/sys/dev/pcf/pcf.c 93165 2002-03-25 21:22:35Z nsouch $
27 *
28 */
29#include <sys/param.h>
30#include <sys/systm.h>
31#include <sys/kernel.h>
32#include <sys/module.h>
33#include <sys/bus.h>
34
35#include <machine/bus.h>
36#include <machine/resource.h>
37#include <sys/rman.h>
38
39#include <isa/isareg.h>
40#include <isa/isavar.h>
41
42#include <i386/isa/isa_device.h>
43
44#include <dev/iicbus/iiconf.h>
45#include "iicbus_if.h"
46
47#define IO_PCFSIZE 2
48
49#define TIMEOUT 9999 /* XXX */
50
51/* Status bits of S1 register (read only) */
52#define nBB 0x01 /* busy when low set/reset by STOP/START*/
53#define LAB 0x02 /* lost arbitration bit in multi-master mode */
54#define AAS 0x04 /* addressed as slave */
55#define LRB 0x08 /* last received byte when not AAS */
56#define AD0 0x08 /* general call received when AAS */
57#define BER 0x10 /* bus error, misplaced START or STOP */
58#define STS 0x20 /* STOP detected in slave receiver mode */
59#define PIN 0x80 /* pending interrupt not (r/w) */
60
61/* Control bits of S1 register (write only) */
62#define ACK 0x01
63#define STO 0x02
64#define STA 0x04
65#define ENI 0x08
66#define ES2 0x10
67#define ES1 0x20
68#define ES0 0x40
69
70#define BUFSIZE 2048
71
72#define SLAVE_TRANSMITTER 0x1
73#define SLAVE_RECEIVER 0x2
74
75#define PCF_DEFAULT_ADDR 0xaa
76
77struct pcf_softc {
78
79 int pcf_base; /* isa port */
80 int pcf_flags;
81 u_char pcf_addr; /* interface I2C address */
82
83 int pcf_slave_mode; /* receiver or transmitter */
84 int pcf_started; /* 1 if start condition sent */
85
86 device_t iicbus; /* the corresponding iicbus */
87
88 int rid_irq, rid_ioport;
89 struct resource *res_irq, *res_ioport;
90 void *intr_cookie;
91};
92
93static int pcf_probe(device_t);
94static int pcf_attach(device_t);
95static void pcfintr(void *arg);
96
97static int pcf_print_child(device_t, device_t);
98
99static int pcf_repeated_start(device_t, u_char, int);
100static int pcf_start(device_t, u_char, int);
101static int pcf_stop(device_t);
102static int pcf_write(device_t, char *, int, int *, int);
103static int pcf_read(device_t, char *, int, int *, int, int);
104static int pcf_rst_card(device_t, u_char, u_char, u_char *);
105
106static device_method_t pcf_methods[] = {
107 /* device interface */
108 DEVMETHOD(device_probe, pcf_probe),
109 DEVMETHOD(device_attach, pcf_attach),
110
111 /* bus interface */
112 DEVMETHOD(bus_print_child, pcf_print_child),
113
114 /* iicbus interface */
115 DEVMETHOD(iicbus_callback, iicbus_null_callback),
116 DEVMETHOD(iicbus_repeated_start, pcf_repeated_start),
117 DEVMETHOD(iicbus_start, pcf_start),
118 DEVMETHOD(iicbus_stop, pcf_stop),
119 DEVMETHOD(iicbus_write, pcf_write),
120 DEVMETHOD(iicbus_read, pcf_read),
121 DEVMETHOD(iicbus_reset, pcf_rst_card),
122
123 { 0, 0 }
124};
125
126static driver_t pcf_driver = {
127 "pcf",
128 pcf_methods,
129 sizeof(struct pcf_softc),
130};
131
132static devclass_t pcf_devclass;
133
134#define DEVTOSOFTC(dev) ((struct pcf_softc *)device_get_softc(dev))
135
136static int
137pcf_probe(device_t pcfdev)
138{
139 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
140 device_t parent = device_get_parent(pcfdev);
141
142 device_set_desc(pcfdev, "PCF8584 I2C bus controller");
143
144 pcf = DEVTOSOFTC(pcfdev);
145 bzero(pcf, sizeof(struct pcf_softc));
146
147 pcf->rid_irq = pcf->rid_ioport = 0;
148 pcf->res_irq = pcf->res_ioport = 0;
149
150 /* IO port is mandatory */
151 pcf->res_ioport = bus_alloc_resource(pcfdev, SYS_RES_IOPORT,
152 &pcf->rid_ioport, 0ul, ~0ul,
153 IO_PCFSIZE, RF_ACTIVE);
154 if (pcf->res_ioport == 0) {
155 device_printf(pcfdev, "cannot reserve I/O port range\n");
156 goto error;
157 }
158 BUS_READ_IVAR(parent, pcfdev, ISA_IVAR_PORT, &pcf->pcf_base);
159
160 pcf->pcf_flags = device_get_flags(pcfdev);
161
162 if (!(pcf->pcf_flags & IIC_POLLED)) {
163 pcf->res_irq = bus_alloc_resource(pcfdev, SYS_RES_IRQ, &pcf->rid_irq,
164 0ul, ~0ul, 1, RF_ACTIVE);
165 if (pcf->res_irq == 0) {
166 device_printf(pcfdev, "can't reserve irq, polled mode.\n");
167 pcf->pcf_flags |= IIC_POLLED;
168 }
169 }
170
171 /* reset the chip */
172 pcf_rst_card(pcfdev, IIC_FASTEST, PCF_DEFAULT_ADDR, NULL);
173
174 return (0);
175error:
176 if (pcf->res_ioport != 0) {
177 bus_deactivate_resource(pcfdev, SYS_RES_IOPORT, pcf->rid_ioport,
178 pcf->res_ioport);
179 bus_release_resource(pcfdev, SYS_RES_IOPORT, pcf->rid_ioport,
180 pcf->res_ioport);
181 }
182 return (ENXIO);
183}
184
185static int
186pcf_attach(device_t pcfdev)
187{
188 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
189 device_t parent = device_get_parent(pcfdev);
190 int error = 0;
191
192 if (pcf->res_irq) {
193 /* default to the tty mask for registration */ /* XXX */
194 error = BUS_SETUP_INTR(parent, pcfdev, pcf->res_irq, INTR_TYPE_NET,
195 pcfintr, pcfdev, &pcf->intr_cookie);
196 if (error)
197 return (error);
198 }
199
200 pcf->iicbus = device_add_child(pcfdev, "iicbus", -1);
201
202 /* probe and attach the iicbus */
203 bus_generic_attach(pcfdev);
204
205 return (0);
206}
207
208static int
209pcf_print_child(device_t bus, device_t dev)
210{
211 struct pcf_softc *pcf = (struct pcf_softc *)device_get_softc(bus);
212 int retval = 0;
213
214 retval += bus_print_child_header(bus, dev);
215 retval += printf(" on %s addr 0x%x\n", device_get_nameunit(bus),
216 (int)pcf->pcf_addr);
217
218 return (retval);
219}
220
221/*
222 * PCF8584 datasheet : when operate at 8 MHz or more, a minimun time of
223 * 6 clocks cycles must be left between two consecutives access
224 */
225#define pcf_nops() DELAY(10)
226
227#define dummy_read(pcf) PCF_GET_S0(pcf)
228#define dummy_write(pcf) PCF_SET_S0(pcf, 0)
229
230/*
231 * Specific register access to PCF8584
232 */
233static void PCF_SET_S0(struct pcf_softc *pcf, int data)
234{
235 outb(pcf->pcf_base, data);
236 pcf_nops();
237}
238
239static void PCF_SET_S1(struct pcf_softc *pcf, int data)
240{
241 outb(pcf->pcf_base+1, data);
242 pcf_nops();
243}
244
245static char PCF_GET_S0(struct pcf_softc *pcf)
246{
247 char data;
248
249 data = inb(pcf->pcf_base);
250 pcf_nops();
251
252 return (data);
253}
254
255static char PCF_GET_S1(struct pcf_softc *pcf)
256{
257 char data;
258
259 data = inb(pcf->pcf_base+1);
260 pcf_nops();
261
262 return (data);
263}
264
265/*
266 * Polling mode for master operations wait for a new
267 * byte incomming or outgoing
268 */
269static int pcf_wait_byte(struct pcf_softc *pcf)
270{
271 int counter = TIMEOUT;
272
273 while (counter--) {
274
275 if ((PCF_GET_S1(pcf) & PIN) == 0)
276 return (0);
277 }
278
279 return (IIC_ETIMEOUT);
280}
281
282static int pcf_stop(device_t pcfdev)
283{
284 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
285
286 /*
287 * Send STOP condition iff the START condition was previously sent.
288 * STOP is sent only once even if a iicbus_stop() is called after
289 * an iicbus_read()... see pcf_read(): the pcf needs to send the stop
290 * before the last char is read.
291 */
292 if (pcf->pcf_started) {
293 /* set stop condition and enable IT */
294 PCF_SET_S1(pcf, PIN|ES0|ENI|STO|ACK);
295
296 pcf->pcf_started = 0;
297 }
298
299 return (0);
300}
301
302
303static int pcf_noack(struct pcf_softc *pcf, int timeout)
304{
305 int noack;
306 int k = timeout/10;
307
308 do {
309 noack = PCF_GET_S1(pcf) & LRB;
310 if (!noack)
311 break;
312 DELAY(10); /* XXX wait 10 us */
313 } while (k--);
314
315 return (noack);
316}
317
318static int pcf_repeated_start(device_t pcfdev, u_char slave, int timeout)
319{
320 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
321 int error = 0;
322
323 /* repeated start */
324 PCF_SET_S1(pcf, ES0|STA|STO|ACK);
325
326 /* set slave address to PCF. Last bit (LSB) must be set correctly
327 * according to transfer direction */
328 PCF_SET_S0(pcf, slave);
329
330 /* wait for address sent, polling */
331 if ((error = pcf_wait_byte(pcf)))
332 goto error;
333
334 /* check for ack */
335 if (pcf_noack(pcf, timeout)) {
336 error = IIC_ENOACK;
337 goto error;
338 }
339
340 return (0);
341
342error:
343 pcf_stop(pcfdev);
344 return (error);
345}
346
347static int pcf_start(device_t pcfdev, u_char slave, int timeout)
348{
349 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
350 int error = 0;
351
352 if ((PCF_GET_S1(pcf) & nBB) == 0)
353 return (IIC_EBUSBSY);
354
355 /* set slave address to PCF. Last bit (LSB) must be set correctly
356 * according to transfer direction */
357 PCF_SET_S0(pcf, slave);
358
359 /* START only */
360 PCF_SET_S1(pcf, PIN|ES0|STA|ACK);
361
362 pcf->pcf_started = 1;
363
364 /* wait for address sent, polling */
365 if ((error = pcf_wait_byte(pcf)))
366 goto error;
367
368 /* check for ACK */
369 if (pcf_noack(pcf, timeout)) {
370 error = IIC_ENOACK;
371 goto error;
372 }
373
374 return (0);
375
376error:
377 pcf_stop(pcfdev);
378 return (error);
379}
380
381static void
382pcfintr(void *arg)
383{
384 device_t pcfdev = (device_t)arg;
385 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
386
387 char data, status, addr;
388 char error = 0;
389
390 status = PCF_GET_S1(pcf);
391
392 if (status & PIN) {
393 device_printf(pcfdev, "spurious interrupt, status=0x%x\n", status & 0xff);
394
395 goto error;
396 }
397
398 if (status & LAB)
399 device_printf(pcfdev, "bus arbitration lost!\n");
400
401 if (status & BER) {
402 error = IIC_EBUSERR;
403 iicbus_intr(pcf->iicbus, INTR_ERROR, &error);
404
405 goto error;
406 }
407
408 do {
409 status = PCF_GET_S1(pcf);
410
411 switch(pcf->pcf_slave_mode) {
412
413 case SLAVE_TRANSMITTER:
414 if (status & LRB) {
415 /* ack interrupt line */
416 dummy_write(pcf);
417
418 /* no ack, don't send anymore */
419 pcf->pcf_slave_mode = SLAVE_RECEIVER;
420
421 iicbus_intr(pcf->iicbus, INTR_NOACK, NULL);
422 break;
423 }
424
425 /* get data from upper code */
426 iicbus_intr(pcf->iicbus, INTR_TRANSMIT, &data);
427
428 PCF_SET_S0(pcf, data);
429 break;
430
431 case SLAVE_RECEIVER:
432 if (status & AAS) {
433 addr = PCF_GET_S0(pcf);
434
435 if (status & AD0)
436 iicbus_intr(pcf->iicbus, INTR_GENERAL, &addr);
437 else
438 iicbus_intr(pcf->iicbus, INTR_START, &addr);
439
440 if (addr & LSB) {
441 pcf->pcf_slave_mode = SLAVE_TRANSMITTER;
442
443 /* get the first char from upper code */
444 iicbus_intr(pcf->iicbus, INTR_TRANSMIT, &data);
445
446 /* send first data byte */
447 PCF_SET_S0(pcf, data);
448 }
449
450 break;
451 }
452
453 /* stop condition received? */
454 if (status & STS) {
455 /* ack interrupt line */
456 dummy_read(pcf);
457
458 /* emulate intr stop condition */
459 iicbus_intr(pcf->iicbus, INTR_STOP, NULL);
460
461 } else {
462 /* get data, ack interrupt line */
463 data = PCF_GET_S0(pcf);
464
465 /* deliver the character */
466 iicbus_intr(pcf->iicbus, INTR_RECEIVE, &data);
467 }
468 break;
469
470 default:
471 panic("%s: unknown slave mode (%d)!", __func__,
472 pcf->pcf_slave_mode);
473 }
474
475 } while ((PCF_GET_S1(pcf) & PIN) == 0);
476
477 return;
478
479error:
480 /* unknown event on bus...reset PCF */
481 PCF_SET_S1(pcf, PIN|ES0|ENI|ACK);
482
483 pcf->pcf_slave_mode = SLAVE_RECEIVER;
484
485 return;
486}
487
488static int pcf_rst_card(device_t pcfdev, u_char speed, u_char addr, u_char *oldaddr)
489{
490 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
491
492 if (oldaddr)
493 *oldaddr = pcf->pcf_addr;
494
495 /* retrieve own address from bus level */
496 if (!addr)
497 pcf->pcf_addr = PCF_DEFAULT_ADDR;
498 else
499 pcf->pcf_addr = addr;
500
501 PCF_SET_S1(pcf, PIN); /* initialize S1 */
502
503 /* own address S'O<>0 */
504 PCF_SET_S0(pcf, pcf->pcf_addr >> 1);
505
506 /* select clock register */
507 PCF_SET_S1(pcf, PIN|ES1);
508
509 /* select bus speed : 18=90kb, 19=45kb, 1A=11kb, 1B=1.5kb */
510 switch (speed) {
511 case IIC_SLOW:
512 PCF_SET_S0(pcf, 0x1b);
513 break;
514
515 case IIC_FAST:
516 PCF_SET_S0(pcf, 0x19);
517 break;
518
519 case IIC_UNKNOWN:
520 case IIC_FASTEST:
521 default:
522 PCF_SET_S0(pcf, 0x18);
523 break;
524 }
525
526 /* set bus on, ack=yes, INT=yes */
527 PCF_SET_S1(pcf, PIN|ES0|ENI|ACK);
528
529 pcf->pcf_slave_mode = SLAVE_RECEIVER;
530
531 return (0);
532}
533
534static int
535pcf_write(device_t pcfdev, char *buf, int len, int *sent, int timeout /* us */)
536{
537 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
538 int bytes, error = 0;
539
540#ifdef PCFDEBUG
541 printf("pcf%d: >> writing %d bytes\n", device_get_unit(pcfdev), len);
542#endif
543
544 bytes = 0;
545 while (len) {
546
547 PCF_SET_S0(pcf, *buf++);
548
549 /* wait for the byte to be send */
550 if ((error = pcf_wait_byte(pcf)))
551 goto error;
552
553 /* check if ack received */
554 if (pcf_noack(pcf, timeout)) {
555 error = IIC_ENOACK;
556 goto error;
557 }
558
559 len --;
560 bytes ++;
561 }
562
563error:
564 *sent = bytes;
565
566#ifdef PCFDEBUG
567 printf("pcf%d: >> %d bytes written (%d)\n",
568 device_get_unit(pcfdev), bytes, error);
569#endif
570
571 return (error);
572}
573
574static int
575pcf_read(device_t pcfdev, char *buf, int len, int *read, int last,
576 int delay /* us */)
577{
578 struct pcf_softc *pcf = DEVTOSOFTC(pcfdev);
579 int bytes, error = 0;
580
581#ifdef PCFDEBUG
582 printf("pcf%d: << reading %d bytes\n", device_get_unit(pcfdev), len);
583#endif
584
585 /* trig the bus to get the first data byte in S0 */
586 if (len) {
587 if (len == 1 && last)
588 /* just one byte to read */
589 PCF_SET_S1(pcf, ES0); /* no ack */
590
591 dummy_read(pcf);
592 }
593
594 bytes = 0;
595 while (len) {
596
597 /* XXX delay needed here */
598
599 /* wait for trigged byte */
600 if ((error = pcf_wait_byte(pcf))) {
601 pcf_stop(pcfdev);
602 goto error;
603 }
604
605 if (len == 1 && last)
606 /* ok, last data byte already in S0, no I2C activity
607 * on next PCF_GET_S0() */
608 pcf_stop(pcfdev);
609
610 else if (len == 2 && last)
611 /* next trigged byte with no ack */
612 PCF_SET_S1(pcf, ES0);
613
614 /* receive byte, trig next byte */
615 *buf++ = PCF_GET_S0(pcf);
616
617 len --;
618 bytes ++;
619 };
620
621error:
622 *read = bytes;
623
624#ifdef PCFDEBUG
625 printf("pcf%d: << %d bytes read (%d)\n",
626 device_get_unit(pcfdev), bytes, error);
627#endif
628
629 return (error);
630}
631
632DRIVER_MODULE(pcf, isa, pcf_driver, pcf_devclass, 0, 0);