1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * ds2490.c USB to one wire bridge
4 *
5 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
6 */
7
8 #include <linux/module.h>
9 #include <linux/kernel.h>
10 #include <linux/mod_devicetable.h>
11 #include <linux/usb.h>
12 #include <linux/slab.h>
13
14 #include <linux/w1.h>
15
16 /* USB Standard */
17 /* USB Control request vendor type */
18 #define VENDOR 0x40
19
20 /* COMMAND TYPE CODES */
21 #define CONTROL_CMD 0x00
22 #define COMM_CMD 0x01
23 #define MODE_CMD 0x02
24
25 /* CONTROL COMMAND CODES */
26 #define CTL_RESET_DEVICE 0x0000
27 #define CTL_START_EXE 0x0001
28 #define CTL_RESUME_EXE 0x0002
29 #define CTL_HALT_EXE_IDLE 0x0003
30 #define CTL_HALT_EXE_DONE 0x0004
31 #define CTL_FLUSH_COMM_CMDS 0x0007
32 #define CTL_FLUSH_RCV_BUFFER 0x0008
33 #define CTL_FLUSH_XMT_BUFFER 0x0009
34 #define CTL_GET_COMM_CMDS 0x000A
35
36 /* MODE COMMAND CODES */
37 #define MOD_PULSE_EN 0x0000
38 #define MOD_SPEED_CHANGE_EN 0x0001
39 #define MOD_1WIRE_SPEED 0x0002
40 #define MOD_STRONG_PU_DURATION 0x0003
41 #define MOD_PULLDOWN_SLEWRATE 0x0004
42 #define MOD_PROG_PULSE_DURATION 0x0005
43 #define MOD_WRITE1_LOWTIME 0x0006
44 #define MOD_DSOW0_TREC 0x0007
45
46 /* COMMUNICATION COMMAND CODES */
47 #define COMM_ERROR_ESCAPE 0x0601
48 #define COMM_SET_DURATION 0x0012
49 #define COMM_BIT_IO 0x0020
50 #define COMM_PULSE 0x0030
51 #define COMM_1_WIRE_RESET 0x0042
52 #define COMM_BYTE_IO 0x0052
53 #define COMM_MATCH_ACCESS 0x0064
54 #define COMM_BLOCK_IO 0x0074
55 #define COMM_READ_STRAIGHT 0x0080
56 #define COMM_DO_RELEASE 0x6092
57 #define COMM_SET_PATH 0x00A2
58 #define COMM_WRITE_SRAM_PAGE 0x00B2
59 #define COMM_WRITE_EPROM 0x00C4
60 #define COMM_READ_CRC_PROT_PAGE 0x00D4
61 #define COMM_READ_REDIRECT_PAGE_CRC 0x21E4
62 #define COMM_SEARCH_ACCESS 0x00F4
63
64 /* Communication command bits */
65 #define COMM_TYPE 0x0008
66 #define COMM_SE 0x0008
67 #define COMM_D 0x0008
68 #define COMM_Z 0x0008
69 #define COMM_CH 0x0008
70 #define COMM_SM 0x0008
71 #define COMM_R 0x0008
72 #define COMM_IM 0x0001
73
74 #define COMM_PS 0x4000
75 #define COMM_PST 0x4000
76 #define COMM_CIB 0x4000
77 #define COMM_RTS 0x4000
78 #define COMM_DT 0x2000
79 #define COMM_SPU 0x1000
80 #define COMM_F 0x0800
81 #define COMM_NTF 0x0400
82 #define COMM_ICP 0x0200
83 #define COMM_RST 0x0100
84
85 #define PULSE_PROG 0x01
86 #define PULSE_SPUE 0x02
87
88 #define BRANCH_MAIN 0xCC
89 #define BRANCH_AUX 0x33
90
91 /* Status flags */
92 #define ST_SPUA 0x01 /* Strong Pull-up is active */
93 #define ST_PRGA 0x02 /* 12V programming pulse is being generated */
94 #define ST_12VP 0x04 /* external 12V programming voltage is present */
95 #define ST_PMOD 0x08 /* DS2490 powered from USB and external sources */
96 #define ST_HALT 0x10 /* DS2490 is currently halted */
97 #define ST_IDLE 0x20 /* DS2490 is currently idle */
98 #define ST_EPOF 0x80
99 /* Status transfer size, 16 bytes status, 16 byte result flags */
100 #define ST_SIZE 0x20
101
102 /* Result Register flags */
103 #define RR_DETECT 0xA5 /* New device detected */
104 #define RR_NRS 0x01 /* Reset no presence or ... */
105 #define RR_SH 0x02 /* short on reset or set path */
106 #define RR_APP 0x04 /* alarming presence on reset */
107 #define RR_VPP 0x08 /* 12V expected not seen */
108 #define RR_CMP 0x10 /* compare error */
109 #define RR_CRC 0x20 /* CRC error detected */
110 #define RR_RDP 0x40 /* redirected page */
111 #define RR_EOS 0x80 /* end of search error */
112
113 #define SPEED_NORMAL 0x00
114 #define SPEED_FLEXIBLE 0x01
115 #define SPEED_OVERDRIVE 0x02
116
117 #define NUM_EP 4
118 #define EP_CONTROL 0
119 #define EP_STATUS 1
120 #define EP_DATA_OUT 2
121 #define EP_DATA_IN 3
122
123 struct ds_device {
124 struct list_head ds_entry;
125
126 struct usb_device *udev;
127 struct usb_interface *intf;
128
129 int ep[NUM_EP];
130
131 /* Strong PullUp
132 * 0: pullup not active, else duration in milliseconds
133 */
134 int spu_sleep;
135 /* spu_bit contains COMM_SPU or 0 depending on if the strong pullup
136 * should be active or not for writes.
137 */
138 u16 spu_bit;
139
140 u8 st_buf[ST_SIZE];
141 u8 byte_buf;
142
143 struct w1_bus_master master;
144 };
145
146 struct ds_status {
147 u8 enable;
148 u8 speed;
149 u8 pullup_dur;
150 u8 ppuls_dur;
151 u8 pulldown_slew;
152 u8 write1_time;
153 u8 write0_time;
154 u8 reserved0;
155 u8 status;
156 u8 command0;
157 u8 command1;
158 u8 command_buffer_status;
159 u8 data_out_buffer_status;
160 u8 data_in_buffer_status;
161 u8 reserved1;
162 u8 reserved2;
163 };
164
165 static LIST_HEAD(ds_devices);
166 static DEFINE_MUTEX(ds_mutex);
167
ds_send_control_cmd(struct ds_device * dev,u16 value,u16 index)168 static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index)
169 {
170 int err;
171
172 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
173 CONTROL_CMD, VENDOR, value, index, NULL, 0, 1000);
174 if (err < 0) {
175 pr_err("Failed to send command control message %x.%x: err=%d.\n",
176 value, index, err);
177 return err;
178 }
179
180 return err;
181 }
182
ds_send_control_mode(struct ds_device * dev,u16 value,u16 index)183 static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index)
184 {
185 int err;
186
187 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
188 MODE_CMD, VENDOR, value, index, NULL, 0, 1000);
189 if (err < 0) {
190 pr_err("Failed to send mode control message %x.%x: err=%d.\n",
191 value, index, err);
192 return err;
193 }
194
195 return err;
196 }
197
ds_send_control(struct ds_device * dev,u16 value,u16 index)198 static int ds_send_control(struct ds_device *dev, u16 value, u16 index)
199 {
200 int err;
201
202 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
203 COMM_CMD, VENDOR, value, index, NULL, 0, 1000);
204 if (err < 0) {
205 pr_err("Failed to send control message %x.%x: err=%d.\n",
206 value, index, err);
207 return err;
208 }
209
210 return err;
211 }
212
ds_print_msg(unsigned char * buf,unsigned char * str,int off)213 static inline void ds_print_msg(unsigned char *buf, unsigned char *str, int off)
214 {
215 pr_info("%45s: %8x\n", str, buf[off]);
216 }
217
ds_dump_status(struct ds_device * dev,unsigned char * buf,int count)218 static void ds_dump_status(struct ds_device *dev, unsigned char *buf, int count)
219 {
220 int i;
221
222 pr_info("0x%x: count=%d, status: ", dev->ep[EP_STATUS], count);
223 for (i = 0; i < count; ++i)
224 pr_info("%02x ", buf[i]);
225 pr_info("\n");
226
227 if (count >= 16) {
228 ds_print_msg(buf, "enable flag", 0);
229 ds_print_msg(buf, "1-wire speed", 1);
230 ds_print_msg(buf, "strong pullup duration", 2);
231 ds_print_msg(buf, "programming pulse duration", 3);
232 ds_print_msg(buf, "pulldown slew rate control", 4);
233 ds_print_msg(buf, "write-1 low time", 5);
234 ds_print_msg(buf, "data sample offset/write-0 recovery time",
235 6);
236 ds_print_msg(buf, "reserved (test register)", 7);
237 ds_print_msg(buf, "device status flags", 8);
238 ds_print_msg(buf, "communication command byte 1", 9);
239 ds_print_msg(buf, "communication command byte 2", 10);
240 ds_print_msg(buf, "communication command buffer status", 11);
241 ds_print_msg(buf, "1-wire data output buffer status", 12);
242 ds_print_msg(buf, "1-wire data input buffer status", 13);
243 ds_print_msg(buf, "reserved", 14);
244 ds_print_msg(buf, "reserved", 15);
245 }
246 for (i = 16; i < count; ++i) {
247 if (buf[i] == RR_DETECT) {
248 ds_print_msg(buf, "new device detect", i);
249 continue;
250 }
251 ds_print_msg(buf, "Result Register Value: ", i);
252 if (buf[i] & RR_NRS)
253 pr_info("NRS: Reset no presence or ...\n");
254 if (buf[i] & RR_SH)
255 pr_info("SH: short on reset or set path\n");
256 if (buf[i] & RR_APP)
257 pr_info("APP: alarming presence on reset\n");
258 if (buf[i] & RR_VPP)
259 pr_info("VPP: 12V expected not seen\n");
260 if (buf[i] & RR_CMP)
261 pr_info("CMP: compare error\n");
262 if (buf[i] & RR_CRC)
263 pr_info("CRC: CRC error detected\n");
264 if (buf[i] & RR_RDP)
265 pr_info("RDP: redirected page\n");
266 if (buf[i] & RR_EOS)
267 pr_info("EOS: end of search error\n");
268 }
269 }
270
ds_recv_status(struct ds_device * dev,struct ds_status * st,bool dump)271 static int ds_recv_status(struct ds_device *dev, struct ds_status *st,
272 bool dump)
273 {
274 int count, err;
275
276 if (st)
277 memset(st, 0, sizeof(*st));
278
279 count = 0;
280 err = usb_interrupt_msg(dev->udev,
281 usb_rcvintpipe(dev->udev,
282 dev->ep[EP_STATUS]),
283 dev->st_buf, sizeof(dev->st_buf),
284 &count, 1000);
285 if (err < 0) {
286 pr_err("Failed to read 1-wire data from 0x%x: err=%d.\n",
287 dev->ep[EP_STATUS], err);
288 return err;
289 }
290
291 if (dump)
292 ds_dump_status(dev, dev->st_buf, count);
293
294 if (st && count >= sizeof(*st))
295 memcpy(st, dev->st_buf, sizeof(*st));
296
297 return count;
298 }
299
ds_reset_device(struct ds_device * dev)300 static void ds_reset_device(struct ds_device *dev)
301 {
302 ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
303 /* Always allow strong pullup which allow individual writes to use
304 * the strong pullup.
305 */
306 if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE))
307 pr_err("ds_reset_device: Error allowing strong pullup\n");
308 /* Chip strong pullup time was cleared. */
309 if (dev->spu_sleep) {
310 /* lower 4 bits are 0, see ds_set_pullup */
311 u8 del = dev->spu_sleep>>4;
312 if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del))
313 pr_err("ds_reset_device: Error setting duration\n");
314 }
315 }
316
ds_recv_data(struct ds_device * dev,unsigned char * buf,int size)317 static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
318 {
319 int count, err;
320
321 /* Careful on size. If size is less than what is available in
322 * the input buffer, the device fails the bulk transfer and
323 * clears the input buffer. It could read the maximum size of
324 * the data buffer, but then do you return the first, last, or
325 * some set of the middle size bytes? As long as the rest of
326 * the code is correct there will be size bytes waiting. A
327 * call to ds_wait_status will wait until the device is idle
328 * and any data to be received would have been available.
329 */
330 count = 0;
331 err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
332 buf, size, &count, 1000);
333 if (err < 0) {
334 pr_info("Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]);
335 usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
336 ds_recv_status(dev, NULL, true);
337 return err;
338 }
339
340 #if 0
341 {
342 int i;
343
344 printk("%s: count=%d: ", __func__, count);
345 for (i = 0; i < count; ++i)
346 printk("%02x ", buf[i]);
347 printk("\n");
348 }
349 #endif
350 return count;
351 }
352
ds_send_data(struct ds_device * dev,unsigned char * buf,int len)353 static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len)
354 {
355 int count, err;
356
357 count = 0;
358 err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), buf, len, &count, 1000);
359 if (err < 0) {
360 pr_err("Failed to write 1-wire data to ep0x%x: "
361 "err=%d.\n", dev->ep[EP_DATA_OUT], err);
362 return err;
363 }
364
365 return err;
366 }
367
368 #if 0
369
370 int ds_stop_pulse(struct ds_device *dev, int limit)
371 {
372 struct ds_status st;
373 int count = 0, err = 0;
374
375 do {
376 err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0);
377 if (err)
378 break;
379 err = ds_send_control(dev, CTL_RESUME_EXE, 0);
380 if (err)
381 break;
382 err = ds_recv_status(dev, &st, false);
383 if (err)
384 break;
385
386 if ((st.status & ST_SPUA) == 0) {
387 err = ds_send_control_mode(dev, MOD_PULSE_EN, 0);
388 if (err)
389 break;
390 }
391 } while (++count < limit);
392
393 return err;
394 }
395
396 int ds_detect(struct ds_device *dev, struct ds_status *st)
397 {
398 int err;
399
400 err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
401 if (err)
402 return err;
403
404 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0);
405 if (err)
406 return err;
407
408 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40);
409 if (err)
410 return err;
411
412 err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG);
413 if (err)
414 return err;
415
416 err = ds_dump_status(dev, st);
417
418 return err;
419 }
420
421 #endif /* 0 */
422
ds_wait_status(struct ds_device * dev,struct ds_status * st)423 static int ds_wait_status(struct ds_device *dev, struct ds_status *st)
424 {
425 int err, count = 0;
426
427 do {
428 st->status = 0;
429 err = ds_recv_status(dev, st, false);
430 #if 0
431 if (err >= 0) {
432 int i;
433 printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err);
434 for (i = 0; i < err; ++i)
435 printk("%02x ", dev->st_buf[i]);
436 printk("\n");
437 }
438 #endif
439 } while (!(st->status & ST_IDLE) && !(err < 0) && ++count < 100);
440
441 if (err >= 16 && st->status & ST_EPOF) {
442 pr_info("Resetting device after ST_EPOF.\n");
443 ds_reset_device(dev);
444 /* Always dump the device status. */
445 count = 101;
446 }
447
448 /* Dump the status for errors or if there is extended return data.
449 * The extended status includes new device detection (maybe someone
450 * can do something with it).
451 */
452 if (err > 16 || count >= 100 || err < 0)
453 ds_dump_status(dev, dev->st_buf, err);
454
455 /* Extended data isn't an error. Well, a short is, but the dump
456 * would have already told the user that and we can't do anything
457 * about it in software anyway.
458 */
459 if (count >= 100 || err < 0)
460 return -1;
461 else
462 return 0;
463 }
464
ds_reset(struct ds_device * dev)465 static int ds_reset(struct ds_device *dev)
466 {
467 int err;
468
469 /* Other potentionally interesting flags for reset.
470 *
471 * COMM_NTF: Return result register feedback. This could be used to
472 * detect some conditions such as short, alarming presence, or
473 * detect if a new device was detected.
474 *
475 * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE:
476 * Select the data transfer rate.
477 */
478 err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL);
479 if (err)
480 return err;
481
482 return 0;
483 }
484
485 #if 0
486 static int ds_set_speed(struct ds_device *dev, int speed)
487 {
488 int err;
489
490 if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE)
491 return -EINVAL;
492
493 if (speed != SPEED_OVERDRIVE)
494 speed = SPEED_FLEXIBLE;
495
496 speed &= 0xff;
497
498 err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed);
499 if (err)
500 return err;
501
502 return err;
503 }
504 #endif /* 0 */
505
ds_set_pullup(struct ds_device * dev,int delay)506 static int ds_set_pullup(struct ds_device *dev, int delay)
507 {
508 int err = 0;
509 u8 del = 1 + (u8)(delay >> 4);
510 /* Just storing delay would not get the trunication and roundup. */
511 int ms = del<<4;
512
513 /* Enable spu_bit if a delay is set. */
514 dev->spu_bit = delay ? COMM_SPU : 0;
515 /* If delay is zero, it has already been disabled, if the time is
516 * the same as the hardware was last programmed to, there is also
517 * nothing more to do. Compare with the recalculated value ms
518 * rather than del or delay which can have a different value.
519 */
520 if (delay == 0 || ms == dev->spu_sleep)
521 return err;
522
523 err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del);
524 if (err)
525 return err;
526
527 dev->spu_sleep = ms;
528
529 return err;
530 }
531
ds_touch_bit(struct ds_device * dev,u8 bit,u8 * tbit)532 static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit)
533 {
534 int err;
535 struct ds_status st;
536
537 err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0),
538 0);
539 if (err)
540 return err;
541
542 ds_wait_status(dev, &st);
543
544 err = ds_recv_data(dev, tbit, sizeof(*tbit));
545 if (err < 0)
546 return err;
547
548 return 0;
549 }
550
551 #if 0
552 static int ds_write_bit(struct ds_device *dev, u8 bit)
553 {
554 int err;
555 struct ds_status st;
556
557 /* Set COMM_ICP to write without a readback. Note, this will
558 * produce one time slot, a down followed by an up with COMM_D
559 * only determing the timing.
560 */
561 err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP |
562 (bit ? COMM_D : 0), 0);
563 if (err)
564 return err;
565
566 ds_wait_status(dev, &st);
567
568 return 0;
569 }
570 #endif
571
ds_write_byte(struct ds_device * dev,u8 byte)572 static int ds_write_byte(struct ds_device *dev, u8 byte)
573 {
574 int err;
575 struct ds_status st;
576
577 err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, byte);
578 if (err)
579 return err;
580
581 if (dev->spu_bit)
582 msleep(dev->spu_sleep);
583
584 err = ds_wait_status(dev, &st);
585 if (err)
586 return err;
587
588 err = ds_recv_data(dev, &dev->byte_buf, 1);
589 if (err < 0)
590 return err;
591
592 return !(byte == dev->byte_buf);
593 }
594
ds_read_byte(struct ds_device * dev,u8 * byte)595 static int ds_read_byte(struct ds_device *dev, u8 *byte)
596 {
597 int err;
598 struct ds_status st;
599
600 err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM, 0xff);
601 if (err)
602 return err;
603
604 ds_wait_status(dev, &st);
605
606 err = ds_recv_data(dev, byte, sizeof(*byte));
607 if (err < 0)
608 return err;
609
610 return 0;
611 }
612
ds_read_block(struct ds_device * dev,u8 * buf,int len)613 static int ds_read_block(struct ds_device *dev, u8 *buf, int len)
614 {
615 struct ds_status st;
616 int err;
617
618 if (len > 64*1024)
619 return -E2BIG;
620
621 memset(buf, 0xFF, len);
622
623 err = ds_send_data(dev, buf, len);
624 if (err < 0)
625 return err;
626
627 err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM, len);
628 if (err)
629 return err;
630
631 ds_wait_status(dev, &st);
632
633 memset(buf, 0x00, len);
634 err = ds_recv_data(dev, buf, len);
635
636 return err;
637 }
638
ds_write_block(struct ds_device * dev,u8 * buf,int len)639 static int ds_write_block(struct ds_device *dev, u8 *buf, int len)
640 {
641 int err;
642 struct ds_status st;
643
644 err = ds_send_data(dev, buf, len);
645 if (err < 0)
646 return err;
647
648 err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, len);
649 if (err)
650 return err;
651
652 if (dev->spu_bit)
653 msleep(dev->spu_sleep);
654
655 ds_wait_status(dev, &st);
656
657 err = ds_recv_data(dev, buf, len);
658 if (err < 0)
659 return err;
660
661 return !(err == len);
662 }
663
ds9490r_search(void * data,struct w1_master * master,u8 search_type,w1_slave_found_callback callback)664 static void ds9490r_search(void *data, struct w1_master *master,
665 u8 search_type, w1_slave_found_callback callback)
666 {
667 /* When starting with an existing id, the first id returned will
668 * be that device (if it is still on the bus most likely).
669 *
670 * If the number of devices found is less than or equal to the
671 * search_limit, that number of IDs will be returned. If there are
672 * more, search_limit IDs will be returned followed by a non-zero
673 * discrepency value.
674 */
675 struct ds_device *dev = data;
676 int err;
677 u16 value, index;
678 struct ds_status st;
679 int search_limit;
680 int found = 0;
681 int i;
682
683 /* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for
684 * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time.
685 */
686 const unsigned long jtime = msecs_to_jiffies(1000*8/75);
687 /* FIFO 128 bytes, bulk packet size 64, read a multiple of the
688 * packet size.
689 */
690 const size_t bufsize = 2 * 64;
691 u64 *buf, *found_ids;
692
693 buf = kmalloc(bufsize, GFP_KERNEL);
694 if (!buf)
695 return;
696
697 /*
698 * We are holding the bus mutex during the scan, but adding devices via the
699 * callback needs the bus to be unlocked. So we queue up found ids here.
700 */
701 found_ids = kmalloc_array(master->max_slave_count, sizeof(u64), GFP_KERNEL);
702 if (!found_ids) {
703 kfree(buf);
704 return;
705 }
706
707 mutex_lock(&master->bus_mutex);
708
709 /* address to start searching at */
710 if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0)
711 goto search_out;
712 master->search_id = 0;
713
714 value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F |
715 COMM_RTS;
716 search_limit = master->max_slave_count;
717 if (search_limit > 255)
718 search_limit = 0;
719 index = search_type | (search_limit << 8);
720 if (ds_send_control(dev, value, index) < 0)
721 goto search_out;
722
723 do {
724 schedule_timeout(jtime);
725
726 err = ds_recv_status(dev, &st, false);
727 if (err < 0 || err < sizeof(st))
728 break;
729
730 if (st.data_in_buffer_status) {
731 /* Bulk in can receive partial ids, but when it does
732 * they fail crc and will be discarded anyway.
733 * That has only been seen when status in buffer
734 * is 0 and bulk is read anyway, so don't read
735 * bulk without first checking if status says there
736 * is data to read.
737 */
738 err = ds_recv_data(dev, (u8 *)buf, bufsize);
739 if (err < 0)
740 break;
741 for (i = 0; i < err/8; ++i) {
742 found_ids[found++] = buf[i];
743 /* can't know if there will be a discrepancy
744 * value after until the next id */
745 if (found == search_limit) {
746 master->search_id = buf[i];
747 break;
748 }
749 }
750 }
751
752 if (test_bit(W1_ABORT_SEARCH, &master->flags))
753 break;
754 } while (!(st.status & (ST_IDLE | ST_HALT)));
755
756 /* only continue the search if some weren't found */
757 if (found <= search_limit) {
758 master->search_id = 0;
759 } else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) {
760 /* Only max_slave_count will be scanned in a search,
761 * but it will start where it left off next search
762 * until all ids are identified and then it will start
763 * over. A continued search will report the previous
764 * last id as the first id (provided it is still on the
765 * bus).
766 */
767 dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, "
768 "will continue next search.\n", __func__,
769 master->max_slave_count);
770 set_bit(W1_WARN_MAX_COUNT, &master->flags);
771 }
772
773 search_out:
774 mutex_unlock(&master->bus_mutex);
775 kfree(buf);
776
777 for (i = 0; i < found; i++) /* run callback for all queued up IDs */
778 callback(master, found_ids[i]);
779 kfree(found_ids);
780 }
781
782 #if 0
783 /*
784 * FIXME: if this disabled code is ever used in the future all ds_send_data()
785 * calls must be changed to use a DMAable buffer.
786 */
787 static int ds_match_access(struct ds_device *dev, u64 init)
788 {
789 int err;
790 struct ds_status st;
791
792 err = ds_send_data(dev, (unsigned char *)&init, sizeof(init));
793 if (err)
794 return err;
795
796 ds_wait_status(dev, &st);
797
798 err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055);
799 if (err)
800 return err;
801
802 ds_wait_status(dev, &st);
803
804 return 0;
805 }
806
807 static int ds_set_path(struct ds_device *dev, u64 init)
808 {
809 int err;
810 struct ds_status st;
811 u8 buf[9];
812
813 memcpy(buf, &init, 8);
814 buf[8] = BRANCH_MAIN;
815
816 err = ds_send_data(dev, buf, sizeof(buf));
817 if (err)
818 return err;
819
820 ds_wait_status(dev, &st);
821
822 err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0);
823 if (err)
824 return err;
825
826 ds_wait_status(dev, &st);
827
828 return 0;
829 }
830
831 #endif /* 0 */
832
ds9490r_touch_bit(void * data,u8 bit)833 static u8 ds9490r_touch_bit(void *data, u8 bit)
834 {
835 struct ds_device *dev = data;
836
837 if (ds_touch_bit(dev, bit, &dev->byte_buf))
838 return 0;
839
840 return dev->byte_buf;
841 }
842
843 #if 0
844 static void ds9490r_write_bit(void *data, u8 bit)
845 {
846 struct ds_device *dev = data;
847
848 ds_write_bit(dev, bit);
849 }
850
851 static u8 ds9490r_read_bit(void *data)
852 {
853 struct ds_device *dev = data;
854 int err;
855
856 err = ds_touch_bit(dev, 1, &dev->byte_buf);
857 if (err)
858 return 0;
859
860 return dev->byte_buf & 1;
861 }
862 #endif
863
ds9490r_write_byte(void * data,u8 byte)864 static void ds9490r_write_byte(void *data, u8 byte)
865 {
866 struct ds_device *dev = data;
867
868 ds_write_byte(dev, byte);
869 }
870
ds9490r_read_byte(void * data)871 static u8 ds9490r_read_byte(void *data)
872 {
873 struct ds_device *dev = data;
874 int err;
875
876 err = ds_read_byte(dev, &dev->byte_buf);
877 if (err)
878 return 0;
879
880 return dev->byte_buf;
881 }
882
ds9490r_write_block(void * data,const u8 * buf,int len)883 static void ds9490r_write_block(void *data, const u8 *buf, int len)
884 {
885 struct ds_device *dev = data;
886 u8 *tbuf;
887
888 if (len <= 0)
889 return;
890
891 tbuf = kmemdup(buf, len, GFP_KERNEL);
892 if (!tbuf)
893 return;
894
895 ds_write_block(dev, tbuf, len);
896
897 kfree(tbuf);
898 }
899
ds9490r_read_block(void * data,u8 * buf,int len)900 static u8 ds9490r_read_block(void *data, u8 *buf, int len)
901 {
902 struct ds_device *dev = data;
903 int err;
904 u8 *tbuf;
905
906 if (len <= 0)
907 return 0;
908
909 tbuf = kmalloc(len, GFP_KERNEL);
910 if (!tbuf)
911 return 0;
912
913 err = ds_read_block(dev, tbuf, len);
914 if (err >= 0)
915 memcpy(buf, tbuf, len);
916
917 kfree(tbuf);
918
919 return err >= 0 ? len : 0;
920 }
921
ds9490r_reset(void * data)922 static u8 ds9490r_reset(void *data)
923 {
924 struct ds_device *dev = data;
925 int err;
926
927 err = ds_reset(dev);
928 if (err)
929 return 1;
930
931 return 0;
932 }
933
ds9490r_set_pullup(void * data,int delay)934 static u8 ds9490r_set_pullup(void *data, int delay)
935 {
936 struct ds_device *dev = data;
937
938 if (ds_set_pullup(dev, delay))
939 return 1;
940
941 return 0;
942 }
943
ds_w1_init(struct ds_device * dev)944 static int ds_w1_init(struct ds_device *dev)
945 {
946 memset(&dev->master, 0, sizeof(struct w1_bus_master));
947
948 /* Reset the device as it can be in a bad state.
949 * This is necessary because a block write will wait for data
950 * to be placed in the output buffer and block any later
951 * commands which will keep accumulating and the device will
952 * not be idle. Another case is removing the ds2490 module
953 * while a bus search is in progress, somehow a few commands
954 * get through, but the input transfers fail leaving data in
955 * the input buffer. This will cause the next read to fail
956 * see the note in ds_recv_data.
957 */
958 ds_reset_device(dev);
959
960 dev->master.data = dev;
961 dev->master.touch_bit = &ds9490r_touch_bit;
962 /* read_bit and write_bit in w1_bus_master are expected to set and
963 * sample the line level. For write_bit that means it is expected to
964 * set it to that value and leave it there. ds2490 only supports an
965 * individual time slot at the lowest level. The requirement from
966 * pulling the bus state down to reading the state is 15us, something
967 * that isn't realistic on the USB bus anyway.
968 dev->master.read_bit = &ds9490r_read_bit;
969 dev->master.write_bit = &ds9490r_write_bit;
970 */
971 dev->master.read_byte = &ds9490r_read_byte;
972 dev->master.write_byte = &ds9490r_write_byte;
973 dev->master.read_block = &ds9490r_read_block;
974 dev->master.write_block = &ds9490r_write_block;
975 dev->master.reset_bus = &ds9490r_reset;
976 dev->master.set_pullup = &ds9490r_set_pullup;
977 dev->master.search = &ds9490r_search;
978
979 return w1_add_master_device(&dev->master);
980 }
981
ds_w1_fini(struct ds_device * dev)982 static void ds_w1_fini(struct ds_device *dev)
983 {
984 w1_remove_master_device(&dev->master);
985 }
986
ds_probe(struct usb_interface * intf,const struct usb_device_id * udev_id)987 static int ds_probe(struct usb_interface *intf,
988 const struct usb_device_id *udev_id)
989 {
990 struct usb_device *udev = interface_to_usbdev(intf);
991 struct usb_endpoint_descriptor *endpoint;
992 struct usb_host_interface *iface_desc;
993 struct ds_device *dev;
994 int i, err, alt;
995
996 dev = kzalloc(sizeof(struct ds_device), GFP_KERNEL);
997 if (!dev) {
998 pr_info("Failed to allocate new DS9490R structure.\n");
999 return -ENOMEM;
1000 }
1001 dev->udev = usb_get_dev(udev);
1002 if (!dev->udev) {
1003 err = -ENOMEM;
1004 goto err_out_free;
1005 }
1006 memset(dev->ep, 0, sizeof(dev->ep));
1007
1008 usb_set_intfdata(intf, dev);
1009
1010 err = usb_reset_configuration(dev->udev);
1011 if (err) {
1012 dev_err(&dev->udev->dev,
1013 "Failed to reset configuration: err=%d.\n", err);
1014 goto err_out_clear;
1015 }
1016
1017 /* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */
1018 alt = 3;
1019 err = usb_set_interface(dev->udev,
1020 intf->cur_altsetting->desc.bInterfaceNumber, alt);
1021 if (err) {
1022 dev_err(&dev->udev->dev, "Failed to set alternative setting %d "
1023 "for %d interface: err=%d.\n", alt,
1024 intf->cur_altsetting->desc.bInterfaceNumber, err);
1025 goto err_out_clear;
1026 }
1027
1028 iface_desc = intf->cur_altsetting;
1029 if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
1030 pr_info("Num endpoints=%d. It is not DS9490R.\n",
1031 iface_desc->desc.bNumEndpoints);
1032 err = -EINVAL;
1033 goto err_out_clear;
1034 }
1035
1036 /*
1037 * This loop doesn'd show control 0 endpoint,
1038 * so we will fill only 1-3 endpoints entry.
1039 */
1040 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
1041 endpoint = &iface_desc->endpoint[i].desc;
1042
1043 dev->ep[i+1] = endpoint->bEndpointAddress;
1044 #if 0
1045 printk("%d: addr=%x, size=%d, dir=%s, type=%x\n",
1046 i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize),
1047 (endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT",
1048 endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK);
1049 #endif
1050 }
1051
1052 err = ds_w1_init(dev);
1053 if (err)
1054 goto err_out_clear;
1055
1056 mutex_lock(&ds_mutex);
1057 list_add_tail(&dev->ds_entry, &ds_devices);
1058 mutex_unlock(&ds_mutex);
1059
1060 return 0;
1061
1062 err_out_clear:
1063 usb_set_intfdata(intf, NULL);
1064 usb_put_dev(dev->udev);
1065 err_out_free:
1066 kfree(dev);
1067 return err;
1068 }
1069
ds_disconnect(struct usb_interface * intf)1070 static void ds_disconnect(struct usb_interface *intf)
1071 {
1072 struct ds_device *dev;
1073
1074 dev = usb_get_intfdata(intf);
1075 if (!dev)
1076 return;
1077
1078 mutex_lock(&ds_mutex);
1079 list_del(&dev->ds_entry);
1080 mutex_unlock(&ds_mutex);
1081
1082 ds_w1_fini(dev);
1083
1084 usb_set_intfdata(intf, NULL);
1085
1086 usb_put_dev(dev->udev);
1087 kfree(dev);
1088 }
1089
1090 static const struct usb_device_id ds_id_table[] = {
1091 { USB_DEVICE(0x04fa, 0x2490) },
1092 { },
1093 };
1094 MODULE_DEVICE_TABLE(usb, ds_id_table);
1095
1096 static struct usb_driver ds_driver = {
1097 .name = "DS9490R",
1098 .probe = ds_probe,
1099 .disconnect = ds_disconnect,
1100 .id_table = ds_id_table,
1101 };
1102 module_usb_driver(ds_driver);
1103
1104 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
1105 MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)");
1106 MODULE_LICENSE("GPL");
1107