1/*
2 * ds2490.c USB to one wire bridge
3 *
4 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
5 *
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/mod_devicetable.h>
25#include <linux/usb.h>
26#include <linux/slab.h>
27
28#include <linux/w1.h>
29
30/* USB Standard */
31/* USB Control request vendor type */
32#define VENDOR 0x40
33
34/* COMMAND TYPE CODES */
35#define CONTROL_CMD 0x00
36#define COMM_CMD 0x01
37#define MODE_CMD 0x02
38
39/* CONTROL COMMAND CODES */
40#define CTL_RESET_DEVICE 0x0000
41#define CTL_START_EXE 0x0001
42#define CTL_RESUME_EXE 0x0002
43#define CTL_HALT_EXE_IDLE 0x0003
44#define CTL_HALT_EXE_DONE 0x0004
45#define CTL_FLUSH_COMM_CMDS 0x0007
46#define CTL_FLUSH_RCV_BUFFER 0x0008
47#define CTL_FLUSH_XMT_BUFFER 0x0009
48#define CTL_GET_COMM_CMDS 0x000A
49
50/* MODE COMMAND CODES */
51#define MOD_PULSE_EN 0x0000
52#define MOD_SPEED_CHANGE_EN 0x0001
53#define MOD_1WIRE_SPEED 0x0002
54#define MOD_STRONG_PU_DURATION 0x0003
55#define MOD_PULLDOWN_SLEWRATE 0x0004
56#define MOD_PROG_PULSE_DURATION 0x0005
57#define MOD_WRITE1_LOWTIME 0x0006
58#define MOD_DSOW0_TREC 0x0007
59
60/* COMMUNICATION COMMAND CODES */
61#define COMM_ERROR_ESCAPE 0x0601
62#define COMM_SET_DURATION 0x0012
63#define COMM_BIT_IO 0x0020
64#define COMM_PULSE 0x0030
65#define COMM_1_WIRE_RESET 0x0042
66#define COMM_BYTE_IO 0x0052
67#define COMM_MATCH_ACCESS 0x0064
68#define COMM_BLOCK_IO 0x0074
69#define COMM_READ_STRAIGHT 0x0080
70#define COMM_DO_RELEASE 0x6092
71#define COMM_SET_PATH 0x00A2
72#define COMM_WRITE_SRAM_PAGE 0x00B2
73#define COMM_WRITE_EPROM 0x00C4
74#define COMM_READ_CRC_PROT_PAGE 0x00D4
75#define COMM_READ_REDIRECT_PAGE_CRC 0x21E4
76#define COMM_SEARCH_ACCESS 0x00F4
77
78/* Communication command bits */
79#define COMM_TYPE 0x0008
80#define COMM_SE 0x0008
81#define COMM_D 0x0008
82#define COMM_Z 0x0008
83#define COMM_CH 0x0008
84#define COMM_SM 0x0008
85#define COMM_R 0x0008
86#define COMM_IM 0x0001
87
88#define COMM_PS 0x4000
89#define COMM_PST 0x4000
90#define COMM_CIB 0x4000
91#define COMM_RTS 0x4000
92#define COMM_DT 0x2000
93#define COMM_SPU 0x1000
94#define COMM_F 0x0800
95#define COMM_NTF 0x0400
96#define COMM_ICP 0x0200
97#define COMM_RST 0x0100
98
99#define PULSE_PROG 0x01
100#define PULSE_SPUE 0x02
101
102#define BRANCH_MAIN 0xCC
103#define BRANCH_AUX 0x33
104
105/* Status flags */
106#define ST_SPUA 0x01 /* Strong Pull-up is active */
107#define ST_PRGA 0x02 /* 12V programming pulse is being generated */
108#define ST_12VP 0x04 /* external 12V programming voltage is present */
109#define ST_PMOD 0x08 /* DS2490 powered from USB and external sources */
110#define ST_HALT 0x10 /* DS2490 is currently halted */
111#define ST_IDLE 0x20 /* DS2490 is currently idle */
112#define ST_EPOF 0x80
113/* Status transfer size, 16 bytes status, 16 byte result flags */
114#define ST_SIZE 0x20
115
116/* Result Register flags */
117#define RR_DETECT 0xA5 /* New device detected */
118#define RR_NRS 0x01 /* Reset no presence or ... */
119#define RR_SH 0x02 /* short on reset or set path */
120#define RR_APP 0x04 /* alarming presence on reset */
121#define RR_VPP 0x08 /* 12V expected not seen */
122#define RR_CMP 0x10 /* compare error */
123#define RR_CRC 0x20 /* CRC error detected */
124#define RR_RDP 0x40 /* redirected page */
125#define RR_EOS 0x80 /* end of search error */
126
127#define SPEED_NORMAL 0x00
128#define SPEED_FLEXIBLE 0x01
129#define SPEED_OVERDRIVE 0x02
130
131#define NUM_EP 4
132#define EP_CONTROL 0
133#define EP_STATUS 1
134#define EP_DATA_OUT 2
135#define EP_DATA_IN 3
136
137struct ds_device {
138 struct list_head ds_entry;
139
140 struct usb_device *udev;
141 struct usb_interface *intf;
142
143 int ep[NUM_EP];
144
145 /* Strong PullUp
146 * 0: pullup not active, else duration in milliseconds
147 */
148 int spu_sleep;
149 /* spu_bit contains COMM_SPU or 0 depending on if the strong pullup
150 * should be active or not for writes.
151 */
152 u16 spu_bit;
153
154 u8 st_buf[ST_SIZE];
155 u8 byte_buf;
156
157 struct w1_bus_master master;
158};
159
160struct ds_status {
161 u8 enable;
162 u8 speed;
163 u8 pullup_dur;
164 u8 ppuls_dur;
165 u8 pulldown_slew;
166 u8 write1_time;
167 u8 write0_time;
168 u8 reserved0;
169 u8 status;
170 u8 command0;
171 u8 command1;
172 u8 command_buffer_status;
173 u8 data_out_buffer_status;
174 u8 data_in_buffer_status;
175 u8 reserved1;
176 u8 reserved2;
177};
178
179static LIST_HEAD(ds_devices);
180static DEFINE_MUTEX(ds_mutex);
181
182static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index)
183{
184 int err;
185
186 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
187 CONTROL_CMD, VENDOR, value, index, NULL, 0, 1000);
188 if (err < 0) {
189 pr_err("Failed to send command control message %x.%x: err=%d.\n",
190 value, index, err);
191 return err;
192 }
193
194 return err;
195}
196
197static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index)
198{
199 int err;
200
201 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
202 MODE_CMD, VENDOR, value, index, NULL, 0, 1000);
203 if (err < 0) {
204 pr_err("Failed to send mode control message %x.%x: err=%d.\n",
205 value, index, err);
206 return err;
207 }
208
209 return err;
210}
211
212static int ds_send_control(struct ds_device *dev, u16 value, u16 index)
213{
214 int err;
215
216 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
217 COMM_CMD, VENDOR, value, index, NULL, 0, 1000);
218 if (err < 0) {
219 pr_err("Failed to send control message %x.%x: err=%d.\n",
220 value, index, err);
221 return err;
222 }
223
224 return err;
225}
226
227static inline void ds_print_msg(unsigned char *buf, unsigned char *str, int off)
228{
229 pr_info("%45s: %8x\n", str, buf[off]);
230}
231
232static void ds_dump_status(struct ds_device *dev, unsigned char *buf, int count)
233{
234 int i;
235
236 pr_info("0x%x: count=%d, status: ", dev->ep[EP_STATUS], count);
237 for (i = 0; i < count; ++i)
238 pr_info("%02x ", buf[i]);
239 pr_info("\n");
240
241 if (count >= 16) {
242 ds_print_msg(buf, "enable flag", 0);
243 ds_print_msg(buf, "1-wire speed", 1);
244 ds_print_msg(buf, "strong pullup duration", 2);
245 ds_print_msg(buf, "programming pulse duration", 3);
246 ds_print_msg(buf, "pulldown slew rate control", 4);
247 ds_print_msg(buf, "write-1 low time", 5);
248 ds_print_msg(buf, "data sample offset/write-0 recovery time",
249 6);
250 ds_print_msg(buf, "reserved (test register)", 7);
251 ds_print_msg(buf, "device status flags", 8);
252 ds_print_msg(buf, "communication command byte 1", 9);
253 ds_print_msg(buf, "communication command byte 2", 10);
254 ds_print_msg(buf, "communication command buffer status", 11);
255 ds_print_msg(buf, "1-wire data output buffer status", 12);
256 ds_print_msg(buf, "1-wire data input buffer status", 13);
257 ds_print_msg(buf, "reserved", 14);
258 ds_print_msg(buf, "reserved", 15);
259 }
260 for (i = 16; i < count; ++i) {
261 if (buf[i] == RR_DETECT) {
262 ds_print_msg(buf, "new device detect", i);
263 continue;
264 }
265 ds_print_msg(buf, "Result Register Value: ", i);
266 if (buf[i] & RR_NRS)
267 pr_info("NRS: Reset no presence or ...\n");
268 if (buf[i] & RR_SH)
269 pr_info("SH: short on reset or set path\n");
270 if (buf[i] & RR_APP)
271 pr_info("APP: alarming presence on reset\n");
272 if (buf[i] & RR_VPP)
273 pr_info("VPP: 12V expected not seen\n");
274 if (buf[i] & RR_CMP)
275 pr_info("CMP: compare error\n");
276 if (buf[i] & RR_CRC)
277 pr_info("CRC: CRC error detected\n");
278 if (buf[i] & RR_RDP)
279 pr_info("RDP: redirected page\n");
280 if (buf[i] & RR_EOS)
281 pr_info("EOS: end of search error\n");
282 }
283}
284
285static int ds_recv_status(struct ds_device *dev, struct ds_status *st,
286 bool dump)
287{
288 int count, err;
289
290 if (st)
291 memset(st, 0, sizeof(*st));
292
293 count = 0;
294 err = usb_interrupt_msg(dev->udev,
295 usb_rcvintpipe(dev->udev,
296 dev->ep[EP_STATUS]),
297 dev->st_buf, sizeof(dev->st_buf),
298 &count, 1000);
299 if (err < 0) {
300 pr_err("Failed to read 1-wire data from 0x%x: err=%d.\n",
301 dev->ep[EP_STATUS], err);
302 return err;
303 }
304
305 if (dump)
306 ds_dump_status(dev, dev->st_buf, count);
307
308 if (st && count >= sizeof(*st))
309 memcpy(st, dev->st_buf, sizeof(*st));
310
311 return count;
312}
313
314static void ds_reset_device(struct ds_device *dev)
315{
316 ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
317 /* Always allow strong pullup which allow individual writes to use
318 * the strong pullup.
319 */
320 if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE))
321 pr_err("ds_reset_device: Error allowing strong pullup\n");
322 /* Chip strong pullup time was cleared. */
323 if (dev->spu_sleep) {
324 /* lower 4 bits are 0, see ds_set_pullup */
325 u8 del = dev->spu_sleep>>4;
326 if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del))
327 pr_err("ds_reset_device: Error setting duration\n");
328 }
329}
330
331static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
332{
333 int count, err;
334
335 /* Careful on size. If size is less than what is available in
336 * the input buffer, the device fails the bulk transfer and
337 * clears the input buffer. It could read the maximum size of
338 * the data buffer, but then do you return the first, last, or
339 * some set of the middle size bytes? As long as the rest of
340 * the code is correct there will be size bytes waiting. A
341 * call to ds_wait_status will wait until the device is idle
342 * and any data to be received would have been available.
343 */
344 count = 0;
345 err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
346 buf, size, &count, 1000);
347 if (err < 0) {
348 pr_info("Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]);
349 usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
350 ds_recv_status(dev, NULL, true);
351 return err;
352 }
353
354#if 0
355 {
356 int i;
357
358 printk("%s: count=%d: ", __func__, count);
359 for (i = 0; i < count; ++i)
360 printk("%02x ", buf[i]);
361 printk("\n");
362 }
363#endif
364 return count;
365}
366
367static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len)
368{
369 int count, err;
370
371 count = 0;
372 err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), buf, len, &count, 1000);
373 if (err < 0) {
374 pr_err("Failed to write 1-wire data to ep0x%x: "
375 "err=%d.\n", dev->ep[EP_DATA_OUT], err);
376 return err;
377 }
378
379 return err;
380}
381
382#if 0
383
384int ds_stop_pulse(struct ds_device *dev, int limit)
385{
386 struct ds_status st;
387 int count = 0, err = 0;
388
389 do {
390 err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0);
391 if (err)
392 break;
393 err = ds_send_control(dev, CTL_RESUME_EXE, 0);
394 if (err)
395 break;
396 err = ds_recv_status(dev, &st, false);
397 if (err)
398 break;
399
400 if ((st.status & ST_SPUA) == 0) {
401 err = ds_send_control_mode(dev, MOD_PULSE_EN, 0);
402 if (err)
403 break;
404 }
405 } while (++count < limit);
406
407 return err;
408}
409
410int ds_detect(struct ds_device *dev, struct ds_status *st)
411{
412 int err;
413
414 err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
415 if (err)
416 return err;
417
418 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0);
419 if (err)
420 return err;
421
422 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40);
423 if (err)
424 return err;
425
426 err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG);
427 if (err)
428 return err;
429
430 err = ds_dump_status(dev, st);
431
432 return err;
433}
434
435#endif /* 0 */
436
437static int ds_wait_status(struct ds_device *dev, struct ds_status *st)
438{
439 int err, count = 0;
440
441 do {
442 st->status = 0;
443 err = ds_recv_status(dev, st, false);
444#if 0
445 if (err >= 0) {
446 int i;
447 printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err);
448 for (i = 0; i < err; ++i)
449 printk("%02x ", dev->st_buf[i]);
450 printk("\n");
451 }
452#endif
453 } while (!(st->status & ST_IDLE) && !(err < 0) && ++count < 100);
454
455 if (err >= 16 && st->status & ST_EPOF) {
456 pr_info("Resetting device after ST_EPOF.\n");
457 ds_reset_device(dev);
458 /* Always dump the device status. */
459 count = 101;
460 }
461
462 /* Dump the status for errors or if there is extended return data.
463 * The extended status includes new device detection (maybe someone
464 * can do something with it).
465 */
466 if (err > 16 || count >= 100 || err < 0)
467 ds_dump_status(dev, dev->st_buf, err);
468
469 /* Extended data isn't an error. Well, a short is, but the dump
470 * would have already told the user that and we can't do anything
471 * about it in software anyway.
472 */
473 if (count >= 100 || err < 0)
474 return -1;
475 else
476 return 0;
477}
478
479static int ds_reset(struct ds_device *dev)
480{
481 int err;
482
483 /* Other potentionally interesting flags for reset.
484 *
485 * COMM_NTF: Return result register feedback. This could be used to
486 * detect some conditions such as short, alarming presence, or
487 * detect if a new device was detected.
488 *
489 * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE:
490 * Select the data transfer rate.
491 */
492 err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL);
493 if (err)
494 return err;
495
496 return 0;
497}
498
499#if 0
500static int ds_set_speed(struct ds_device *dev, int speed)
501{
502 int err;
503
504 if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE)
505 return -EINVAL;
506
507 if (speed != SPEED_OVERDRIVE)
508 speed = SPEED_FLEXIBLE;
509
510 speed &= 0xff;
511
512 err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed);
513 if (err)
514 return err;
515
516 return err;
517}
518#endif /* 0 */
519
520static int ds_set_pullup(struct ds_device *dev, int delay)
521{
522 int err = 0;
523 u8 del = 1 + (u8)(delay >> 4);
524 /* Just storing delay would not get the trunication and roundup. */
525 int ms = del<<4;
526
527 /* Enable spu_bit if a delay is set. */
528 dev->spu_bit = delay ? COMM_SPU : 0;
529 /* If delay is zero, it has already been disabled, if the time is
530 * the same as the hardware was last programmed to, there is also
531 * nothing more to do. Compare with the recalculated value ms
532 * rather than del or delay which can have a different value.
533 */
534 if (delay == 0 || ms == dev->spu_sleep)
535 return err;
536
537 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del);
538 if (err)
539 return err;
540
541 dev->spu_sleep = ms;
542
543 return err;
544}
545
546static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit)
547{
548 int err;
549 struct ds_status st;
550
551 err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0),
552 0);
553 if (err)
554 return err;
555
556 ds_wait_status(dev, &st);
557
558 err = ds_recv_data(dev, tbit, sizeof(*tbit));
559 if (err < 0)
560 return err;
561
562 return 0;
563}
564
565#if 0
566static int ds_write_bit(struct ds_device *dev, u8 bit)
567{
568 int err;
569 struct ds_status st;
570
571 /* Set COMM_ICP to write without a readback. Note, this will
572 * produce one time slot, a down followed by an up with COMM_D
573 * only determing the timing.
574 */
575 err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP |
576 (bit ? COMM_D : 0), 0);
577 if (err)
578 return err;
579
580 ds_wait_status(dev, &st);
581
582 return 0;
583}
584#endif
585
586static int ds_write_byte(struct ds_device *dev, u8 byte)
587{
588 int err;
589 struct ds_status st;
590
591 err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, byte);
592 if (err)
593 return err;
594
595 if (dev->spu_bit)
596 msleep(dev->spu_sleep);
597
598 err = ds_wait_status(dev, &st);
599 if (err)
600 return err;
601
602 err = ds_recv_data(dev, &dev->byte_buf, 1);
603 if (err < 0)
604 return err;
605
606 return !(byte == dev->byte_buf);
607}
608
609static int ds_read_byte(struct ds_device *dev, u8 *byte)
610{
611 int err;
612 struct ds_status st;
613
614 err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM, 0xff);
615 if (err)
616 return err;
617
618 ds_wait_status(dev, &st);
619
620 err = ds_recv_data(dev, byte, sizeof(*byte));
621 if (err < 0)
622 return err;
623
624 return 0;
625}
626
627static int ds_read_block(struct ds_device *dev, u8 *buf, int len)
628{
629 struct ds_status st;
630 int err;
631
632 if (len > 64*1024)
633 return -E2BIG;
634
635 memset(buf, 0xFF, len);
636
637 err = ds_send_data(dev, buf, len);
638 if (err < 0)
639 return err;
640
641 err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM, len);
642 if (err)
643 return err;
644
645 ds_wait_status(dev, &st);
646
647 memset(buf, 0x00, len);
648 err = ds_recv_data(dev, buf, len);
649
650 return err;
651}
652
653static int ds_write_block(struct ds_device *dev, u8 *buf, int len)
654{
655 int err;
656 struct ds_status st;
657
658 err = ds_send_data(dev, buf, len);
659 if (err < 0)
660 return err;
661
662 err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, len);
663 if (err)
664 return err;
665
666 if (dev->spu_bit)
667 msleep(dev->spu_sleep);
668
669 ds_wait_status(dev, &st);
670
671 err = ds_recv_data(dev, buf, len);
672 if (err < 0)
673 return err;
674
675 return !(err == len);
676}
677
678static void ds9490r_search(void *data, struct w1_master *master,
679 u8 search_type, w1_slave_found_callback callback)
680{
681 /* When starting with an existing id, the first id returned will
682 * be that device (if it is still on the bus most likely).
683 *
684 * If the number of devices found is less than or equal to the
685 * search_limit, that number of IDs will be returned. If there are
686 * more, search_limit IDs will be returned followed by a non-zero
687 * discrepency value.
688 */
689 struct ds_device *dev = data;
690 int err;
691 u16 value, index;
692 struct ds_status st;
693 int search_limit;
694 int found = 0;
695 int i;
696
697 /* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for
698 * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time.
699 */
700 const unsigned long jtime = msecs_to_jiffies(1000*8/75);
701 /* FIFO 128 bytes, bulk packet size 64, read a multiple of the
702 * packet size.
703 */
704 const size_t bufsize = 2 * 64;
705 u64 *buf;
706
707 buf = kmalloc(bufsize, GFP_KERNEL);
708 if (!buf)
709 return;
710
711 mutex_lock(&master->bus_mutex);
712
713 /* address to start searching at */
714 if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0)
715 goto search_out;
716 master->search_id = 0;
717
718 value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F |
719 COMM_RTS;
720 search_limit = master->max_slave_count;
721 if (search_limit > 255)
722 search_limit = 0;
723 index = search_type | (search_limit << 8);
724 if (ds_send_control(dev, value, index) < 0)
725 goto search_out;
726
727 do {
728 schedule_timeout(jtime);
729
730 err = ds_recv_status(dev, &st, false);
731 if (err < 0 || err < sizeof(st))
732 break;
733
734 if (st.data_in_buffer_status) {
735 /* Bulk in can receive partial ids, but when it does
736 * they fail crc and will be discarded anyway.
737 * That has only been seen when status in buffer
738 * is 0 and bulk is read anyway, so don't read
739 * bulk without first checking if status says there
740 * is data to read.
741 */
742 err = ds_recv_data(dev, (u8 *)buf, bufsize);
743 if (err < 0)
744 break;
745 for (i = 0; i < err/8; ++i) {
746 ++found;
747 if (found <= search_limit)
748 callback(master, buf[i]);
749 /* can't know if there will be a discrepancy
750 * value after until the next id */
751 if (found == search_limit)
752 master->search_id = buf[i];
753 }
754 }
755
756 if (test_bit(W1_ABORT_SEARCH, &master->flags))
757 break;
758 } while (!(st.status & (ST_IDLE | ST_HALT)));
759
760 /* only continue the search if some weren't found */
761 if (found <= search_limit) {
762 master->search_id = 0;
763 } else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) {
764 /* Only max_slave_count will be scanned in a search,
765 * but it will start where it left off next search
766 * until all ids are identified and then it will start
767 * over. A continued search will report the previous
768 * last id as the first id (provided it is still on the
769 * bus).
770 */
771 dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, "
772 "will continue next search.\n", __func__,
773 master->max_slave_count);
774 set_bit(W1_WARN_MAX_COUNT, &master->flags);
775 }
776search_out:
777 mutex_unlock(&master->bus_mutex);
778 kfree(buf);
779}
780
781#if 0
782/*
783 * FIXME: if this disabled code is ever used in the future all ds_send_data()
784 * calls must be changed to use a DMAable buffer.
785 */
786static int ds_match_access(struct ds_device *dev, u64 init)
787{
788 int err;
789 struct ds_status st;
790
791 err = ds_send_data(dev, (unsigned char *)&init, sizeof(init));
792 if (err)
793 return err;
794
795 ds_wait_status(dev, &st);
796
797 err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055);
798 if (err)
799 return err;
800
801 ds_wait_status(dev, &st);
802
803 return 0;
804}
805
806static int ds_set_path(struct ds_device *dev, u64 init)
807{
808 int err;
809 struct ds_status st;
810 u8 buf[9];
811
812 memcpy(buf, &init, 8);
813 buf[8] = BRANCH_MAIN;
814
815 err = ds_send_data(dev, buf, sizeof(buf));
816 if (err)
817 return err;
818
819 ds_wait_status(dev, &st);
820
821 err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0);
822 if (err)
823 return err;
824
825 ds_wait_status(dev, &st);
826
827 return 0;
828}
829
830#endif /* 0 */
831
832static u8 ds9490r_touch_bit(void *data, u8 bit)
833{
834 struct ds_device *dev = data;
835
836 if (ds_touch_bit(dev, bit, &dev->byte_buf))
837 return 0;
838
839 return dev->byte_buf;
840}
841
842#if 0
843static void ds9490r_write_bit(void *data, u8 bit)
844{
845 struct ds_device *dev = data;
846
847 ds_write_bit(dev, bit);
848}
849
850static u8 ds9490r_read_bit(void *data)
851{
852 struct ds_device *dev = data;
853 int err;
854
855 err = ds_touch_bit(dev, 1, &dev->byte_buf);
856 if (err)
857 return 0;
858
859 return dev->byte_buf & 1;
860}
861#endif
862
863static void ds9490r_write_byte(void *data, u8 byte)
864{
865 struct ds_device *dev = data;
866
867 ds_write_byte(dev, byte);
868}
869
870static u8 ds9490r_read_byte(void *data)
871{
872 struct ds_device *dev = data;
873 int err;
874
875 err = ds_read_byte(dev, &dev->byte_buf);
876 if (err)
877 return 0;
878
879 return dev->byte_buf;
880}
881
882static void ds9490r_write_block(void *data, const u8 *buf, int len)
883{
884 struct ds_device *dev = data;
885 u8 *tbuf;
886
887 if (len <= 0)
888 return;
889
890 tbuf = kmemdup(buf, len, GFP_KERNEL);
891 if (!tbuf)
892 return;
893
894 ds_write_block(dev, tbuf, len);
895
896 kfree(tbuf);
897}
898
899static u8 ds9490r_read_block(void *data, u8 *buf, int len)
900{
901 struct ds_device *dev = data;
902 int err;
903 u8 *tbuf;
904
905 if (len <= 0)
906 return 0;
907
908 tbuf = kmalloc(len, GFP_KERNEL);
909 if (!tbuf)
910 return 0;
911
912 err = ds_read_block(dev, tbuf, len);
913 if (err >= 0)
914 memcpy(buf, tbuf, len);
915
916 kfree(tbuf);
917
918 return err >= 0 ? len : 0;
919}
920
921static u8 ds9490r_reset(void *data)
922{
923 struct ds_device *dev = data;
924 int err;
925
926 err = ds_reset(dev);
927 if (err)
928 return 1;
929
930 return 0;
931}
932
933static u8 ds9490r_set_pullup(void *data, int delay)
934{
935 struct ds_device *dev = data;
936
937 if (ds_set_pullup(dev, delay))
938 return 1;
939
940 return 0;
941}
942
943static int ds_w1_init(struct ds_device *dev)
944{
945 memset(&dev->master, 0, sizeof(struct w1_bus_master));
946
947 /* Reset the device as it can be in a bad state.
948 * This is necessary because a block write will wait for data
949 * to be placed in the output buffer and block any later
950 * commands which will keep accumulating and the device will
951 * not be idle. Another case is removing the ds2490 module
952 * while a bus search is in progress, somehow a few commands
953 * get through, but the input transfers fail leaving data in
954 * the input buffer. This will cause the next read to fail
955 * see the note in ds_recv_data.
956 */
957 ds_reset_device(dev);
958
959 dev->master.data = dev;
960 dev->master.touch_bit = &ds9490r_touch_bit;
961 /* read_bit and write_bit in w1_bus_master are expected to set and
962 * sample the line level. For write_bit that means it is expected to
963 * set it to that value and leave it there. ds2490 only supports an
964 * individual time slot at the lowest level. The requirement from
965 * pulling the bus state down to reading the state is 15us, something
966 * that isn't realistic on the USB bus anyway.
967 dev->master.read_bit = &ds9490r_read_bit;
968 dev->master.write_bit = &ds9490r_write_bit;
969 */
970 dev->master.read_byte = &ds9490r_read_byte;
971 dev->master.write_byte = &ds9490r_write_byte;
972 dev->master.read_block = &ds9490r_read_block;
973 dev->master.write_block = &ds9490r_write_block;
974 dev->master.reset_bus = &ds9490r_reset;
975 dev->master.set_pullup = &ds9490r_set_pullup;
976 dev->master.search = &ds9490r_search;
977
978 return w1_add_master_device(&dev->master);
979}
980
981static void ds_w1_fini(struct ds_device *dev)
982{
983 w1_remove_master_device(&dev->master);
984}
985
986static int ds_probe(struct usb_interface *intf,
987 const struct usb_device_id *udev_id)
988{
989 struct usb_device *udev = interface_to_usbdev(intf);
990 struct usb_endpoint_descriptor *endpoint;
991 struct usb_host_interface *iface_desc;
992 struct ds_device *dev;
993 int i, err, alt;
994
995 dev = kzalloc(sizeof(struct ds_device), GFP_KERNEL);
996 if (!dev) {
997 pr_info("Failed to allocate new DS9490R structure.\n");
998 return -ENOMEM;
999 }
1000 dev->udev = usb_get_dev(udev);
1001 if (!dev->udev) {
1002 err = -ENOMEM;
1003 goto err_out_free;
1004 }
1005 memset(dev->ep, 0, sizeof(dev->ep));
1006
1007 usb_set_intfdata(intf, dev);
1008
1009 err = usb_reset_configuration(dev->udev);
1010 if (err) {
1011 dev_err(&dev->udev->dev,
1012 "Failed to reset configuration: err=%d.\n", err);
1013 goto err_out_clear;
1014 }
1015
1016 /* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */
1017 alt = 3;
1018 err = usb_set_interface(dev->udev,
1019 intf->altsetting[alt].desc.bInterfaceNumber, alt);
1020 if (err) {
1021 dev_err(&dev->udev->dev, "Failed to set alternative setting %d "
1022 "for %d interface: err=%d.\n", alt,
1023 intf->altsetting[alt].desc.bInterfaceNumber, err);
1024 goto err_out_clear;
1025 }
1026
1027 iface_desc = &intf->altsetting[alt];
1028 if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
1029 pr_info("Num endpoints=%d. It is not DS9490R.\n",
1030 iface_desc->desc.bNumEndpoints);
1031 err = -EINVAL;
1032 goto err_out_clear;
1033 }
1034
1035 /*
1036 * This loop doesn'd show control 0 endpoint,
1037 * so we will fill only 1-3 endpoints entry.
1038 */
1039 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
1040 endpoint = &iface_desc->endpoint[i].desc;
1041
1042 dev->ep[i+1] = endpoint->bEndpointAddress;
1043#if 0
1044 printk("%d: addr=%x, size=%d, dir=%s, type=%x\n",
1045 i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize),
1046 (endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT",
1047 endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK);
1048#endif
1049 }
1050
1051 err = ds_w1_init(dev);
1052 if (err)
1053 goto err_out_clear;
1054
1055 mutex_lock(&ds_mutex);
1056 list_add_tail(&dev->ds_entry, &ds_devices);
1057 mutex_unlock(&ds_mutex);
1058
1059 return 0;
1060
1061err_out_clear:
1062 usb_set_intfdata(intf, NULL);
1063 usb_put_dev(dev->udev);
1064err_out_free:
1065 kfree(dev);
1066 return err;
1067}
1068
1069static void ds_disconnect(struct usb_interface *intf)
1070{
1071 struct ds_device *dev;
1072
1073 dev = usb_get_intfdata(intf);
1074 if (!dev)
1075 return;
1076
1077 mutex_lock(&ds_mutex);
1078 list_del(&dev->ds_entry);
1079 mutex_unlock(&ds_mutex);
1080
1081 ds_w1_fini(dev);
1082
1083 usb_set_intfdata(intf, NULL);
1084
1085 usb_put_dev(dev->udev);
1086 kfree(dev);
1087}
1088
1089static const struct usb_device_id ds_id_table[] = {
1090 { USB_DEVICE(0x04fa, 0x2490) },
1091 { },
1092};
1093MODULE_DEVICE_TABLE(usb, ds_id_table);
1094
1095static struct usb_driver ds_driver = {
1096 .name = "DS9490R",
1097 .probe = ds_probe,
1098 .disconnect = ds_disconnect,
1099 .id_table = ds_id_table,
1100};
1101module_usb_driver(ds_driver);
1102
1103MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
1104MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)");
1105MODULE_LICENSE("GPL");
1106