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 | |
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: dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), |
173 | CONTROL_CMD, VENDOR, value, index, NULL, size: 0, timeout: 1000); |
174 | if (err < 0) { |
175 | dev_err(&dev->udev->dev, |
176 | "Failed to send command control message %x.%x: err=%d.\n" , |
177 | value, index, err); |
178 | return err; |
179 | } |
180 | |
181 | return err; |
182 | } |
183 | |
184 | static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index) |
185 | { |
186 | int err; |
187 | |
188 | err = usb_control_msg(dev: dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), |
189 | MODE_CMD, VENDOR, value, index, NULL, size: 0, timeout: 1000); |
190 | if (err < 0) { |
191 | dev_err(&dev->udev->dev, |
192 | "Failed to send mode control message %x.%x: err=%d.\n" , |
193 | value, index, err); |
194 | return err; |
195 | } |
196 | |
197 | return err; |
198 | } |
199 | |
200 | static int ds_send_control(struct ds_device *dev, u16 value, u16 index) |
201 | { |
202 | int err; |
203 | |
204 | err = usb_control_msg(dev: dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), |
205 | COMM_CMD, VENDOR, value, index, NULL, size: 0, timeout: 1000); |
206 | if (err < 0) { |
207 | dev_err(&dev->udev->dev, |
208 | "Failed to send control message %x.%x: err=%d.\n" , |
209 | value, index, err); |
210 | return err; |
211 | } |
212 | |
213 | return err; |
214 | } |
215 | |
216 | static void ds_dump_status(struct ds_device *ds_dev, unsigned char *buf, int count) |
217 | { |
218 | struct device *dev = &ds_dev->udev->dev; |
219 | int i; |
220 | |
221 | dev_info(dev, "ep_status=0x%x, count=%d, status=%*phC" , |
222 | ds_dev->ep[EP_STATUS], count, count, buf); |
223 | |
224 | if (count >= 16) { |
225 | dev_dbg(dev, "enable flag: 0x%02x" , buf[0]); |
226 | dev_dbg(dev, "1-wire speed: 0x%02x" , buf[1]); |
227 | dev_dbg(dev, "strong pullup duration: 0x%02x" , buf[2]); |
228 | dev_dbg(dev, "programming pulse duration: 0x%02x" , buf[3]); |
229 | dev_dbg(dev, "pulldown slew rate control: 0x%02x" , buf[4]); |
230 | dev_dbg(dev, "write-1 low time: 0x%02x" , buf[5]); |
231 | dev_dbg(dev, "data sample offset/write-0 recovery time: 0x%02x" , buf[6]); |
232 | dev_dbg(dev, "reserved (test register): 0x%02x" , buf[7]); |
233 | dev_dbg(dev, "device status flags: 0x%02x" , buf[8]); |
234 | dev_dbg(dev, "communication command byte 1: 0x%02x" , buf[9]); |
235 | dev_dbg(dev, "communication command byte 2: 0x%02x" , buf[10]); |
236 | dev_dbg(dev, "communication command buffer status: 0x%02x" , buf[11]); |
237 | dev_dbg(dev, "1-wire data output buffer status: 0x%02x" , buf[12]); |
238 | dev_dbg(dev, "1-wire data input buffer status: 0x%02x" , buf[13]); |
239 | dev_dbg(dev, "reserved: 0x%02x" , buf[14]); |
240 | dev_dbg(dev, "reserved: 0x%02x" , buf[15]); |
241 | } |
242 | |
243 | for (i = 16; i < count; ++i) { |
244 | if (buf[i] == RR_DETECT) { |
245 | dev_dbg(dev, "New device detect.\n" ); |
246 | continue; |
247 | } |
248 | dev_dbg(dev, "Result Register Value: 0x%02x" , buf[i]); |
249 | if (buf[i] & RR_NRS) |
250 | dev_dbg(dev, "NRS: Reset no presence or ...\n" ); |
251 | if (buf[i] & RR_SH) |
252 | dev_dbg(dev, "SH: short on reset or set path\n" ); |
253 | if (buf[i] & RR_APP) |
254 | dev_dbg(dev, "APP: alarming presence on reset\n" ); |
255 | if (buf[i] & RR_VPP) |
256 | dev_dbg(dev, "VPP: 12V expected not seen\n" ); |
257 | if (buf[i] & RR_CMP) |
258 | dev_dbg(dev, "CMP: compare error\n" ); |
259 | if (buf[i] & RR_CRC) |
260 | dev_dbg(dev, "CRC: CRC error detected\n" ); |
261 | if (buf[i] & RR_RDP) |
262 | dev_dbg(dev, "RDP: redirected page\n" ); |
263 | if (buf[i] & RR_EOS) |
264 | dev_dbg(dev, "EOS: end of search error\n" ); |
265 | } |
266 | } |
267 | |
268 | static int ds_recv_status(struct ds_device *dev, struct ds_status *st) |
269 | { |
270 | int count, err; |
271 | |
272 | if (st) |
273 | memset(st, 0, sizeof(*st)); |
274 | |
275 | count = 0; |
276 | err = usb_interrupt_msg(usb_dev: dev->udev, |
277 | usb_rcvintpipe(dev->udev, |
278 | dev->ep[EP_STATUS]), |
279 | data: dev->st_buf, len: sizeof(dev->st_buf), |
280 | actual_length: &count, timeout: 1000); |
281 | if (err < 0) { |
282 | dev_err(&dev->udev->dev, |
283 | "Failed to read 1-wire data from 0x%x: err=%d.\n" , |
284 | dev->ep[EP_STATUS], err); |
285 | return err; |
286 | } |
287 | |
288 | if (st && count >= sizeof(*st)) |
289 | memcpy(st, dev->st_buf, sizeof(*st)); |
290 | |
291 | return count; |
292 | } |
293 | |
294 | static void ds_reset_device(struct ds_device *dev) |
295 | { |
296 | ds_send_control_cmd(dev, CTL_RESET_DEVICE, index: 0); |
297 | /* Always allow strong pullup which allow individual writes to use |
298 | * the strong pullup. |
299 | */ |
300 | if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE)) |
301 | dev_err(&dev->udev->dev, |
302 | "%s: Error allowing strong pullup\n" , __func__); |
303 | /* Chip strong pullup time was cleared. */ |
304 | if (dev->spu_sleep) { |
305 | /* lower 4 bits are 0, see ds_set_pullup */ |
306 | u8 del = dev->spu_sleep>>4; |
307 | |
308 | if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, index: del)) |
309 | dev_err(&dev->udev->dev, |
310 | "%s: Error setting duration\n" , __func__); |
311 | } |
312 | } |
313 | |
314 | static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size) |
315 | { |
316 | int count, err; |
317 | |
318 | /* Careful on size. If size is less than what is available in |
319 | * the input buffer, the device fails the bulk transfer and |
320 | * clears the input buffer. It could read the maximum size of |
321 | * the data buffer, but then do you return the first, last, or |
322 | * some set of the middle size bytes? As long as the rest of |
323 | * the code is correct there will be size bytes waiting. A |
324 | * call to ds_wait_status will wait until the device is idle |
325 | * and any data to be received would have been available. |
326 | */ |
327 | count = 0; |
328 | err = usb_bulk_msg(usb_dev: dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]), |
329 | data: buf, len: size, actual_length: &count, timeout: 1000); |
330 | if (err < 0) { |
331 | int recv_len; |
332 | |
333 | dev_info(&dev->udev->dev, "Clearing ep0x%x.\n" , dev->ep[EP_DATA_IN]); |
334 | usb_clear_halt(dev: dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN])); |
335 | |
336 | /* status might tell us why endpoint is stuck? */ |
337 | recv_len = ds_recv_status(dev, NULL); |
338 | if (recv_len >= 0) |
339 | ds_dump_status(ds_dev: dev, buf: dev->st_buf, count: recv_len); |
340 | |
341 | return err; |
342 | } |
343 | |
344 | #if 0 |
345 | { |
346 | int i; |
347 | |
348 | printk("%s: count=%d: " , __func__, count); |
349 | for (i = 0; i < count; ++i) |
350 | printk("%02x " , buf[i]); |
351 | printk("\n" ); |
352 | } |
353 | #endif |
354 | return count; |
355 | } |
356 | |
357 | static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len) |
358 | { |
359 | int count, err; |
360 | |
361 | count = 0; |
362 | err = usb_bulk_msg(usb_dev: dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), data: buf, len, actual_length: &count, timeout: 1000); |
363 | if (err < 0) { |
364 | dev_err(&dev->udev->dev, "Failed to write 1-wire data to ep0x%x: " |
365 | "err=%d.\n" , dev->ep[EP_DATA_OUT], err); |
366 | return err; |
367 | } |
368 | |
369 | return err; |
370 | } |
371 | |
372 | #if 0 |
373 | |
374 | int ds_stop_pulse(struct ds_device *dev, int limit) |
375 | { |
376 | struct ds_status st; |
377 | int count = 0, err = 0; |
378 | |
379 | do { |
380 | err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0); |
381 | if (err) |
382 | break; |
383 | err = ds_send_control(dev, CTL_RESUME_EXE, 0); |
384 | if (err) |
385 | break; |
386 | err = ds_recv_status(dev, &st); |
387 | if (err) |
388 | break; |
389 | |
390 | if ((st.status & ST_SPUA) == 0) { |
391 | err = ds_send_control_mode(dev, MOD_PULSE_EN, 0); |
392 | if (err) |
393 | break; |
394 | } |
395 | } while (++count < limit); |
396 | |
397 | return err; |
398 | } |
399 | |
400 | int ds_detect(struct ds_device *dev, struct ds_status *st) |
401 | { |
402 | int err; |
403 | |
404 | err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0); |
405 | if (err) |
406 | return err; |
407 | |
408 | err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0); |
409 | if (err) |
410 | return err; |
411 | |
412 | err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40); |
413 | if (err) |
414 | return err; |
415 | |
416 | err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG); |
417 | if (err) |
418 | return err; |
419 | |
420 | err = ds_dump_status(dev, st); |
421 | |
422 | return err; |
423 | } |
424 | |
425 | #endif /* 0 */ |
426 | |
427 | static int ds_wait_status(struct ds_device *dev, struct ds_status *st) |
428 | { |
429 | int err, count = 0; |
430 | |
431 | do { |
432 | st->status = 0; |
433 | err = ds_recv_status(dev, st); |
434 | #if 0 |
435 | if (err >= 0) { |
436 | int i; |
437 | printk("0x%x: count=%d, status: " , dev->ep[EP_STATUS], err); |
438 | for (i = 0; i < err; ++i) |
439 | printk("%02x " , dev->st_buf[i]); |
440 | printk("\n" ); |
441 | } |
442 | #endif |
443 | } while (!(st->status & ST_IDLE) && !(err < 0) && ++count < 100); |
444 | |
445 | if (err >= 16 && st->status & ST_EPOF) { |
446 | dev_info(&dev->udev->dev, "Resetting device after ST_EPOF.\n" ); |
447 | ds_reset_device(dev); |
448 | /* Always dump the device status. */ |
449 | count = 101; |
450 | } |
451 | |
452 | /* Dump the status for errors or if there is extended return data. |
453 | * The extended status includes new device detection (maybe someone |
454 | * can do something with it). |
455 | */ |
456 | if (err > 16 || count >= 100 || err < 0) |
457 | ds_dump_status(ds_dev: dev, buf: dev->st_buf, count: err); |
458 | |
459 | /* Extended data isn't an error. Well, a short is, but the dump |
460 | * would have already told the user that and we can't do anything |
461 | * about it in software anyway. |
462 | */ |
463 | if (count >= 100 || err < 0) |
464 | return -1; |
465 | else |
466 | return 0; |
467 | } |
468 | |
469 | static int ds_reset(struct ds_device *dev) |
470 | { |
471 | int err; |
472 | |
473 | /* Other potentionally interesting flags for reset. |
474 | * |
475 | * COMM_NTF: Return result register feedback. This could be used to |
476 | * detect some conditions such as short, alarming presence, or |
477 | * detect if a new device was detected. |
478 | * |
479 | * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE: |
480 | * Select the data transfer rate. |
481 | */ |
482 | err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL); |
483 | if (err) |
484 | return err; |
485 | |
486 | return 0; |
487 | } |
488 | |
489 | #if 0 |
490 | static int ds_set_speed(struct ds_device *dev, int speed) |
491 | { |
492 | int err; |
493 | |
494 | if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE) |
495 | return -EINVAL; |
496 | |
497 | if (speed != SPEED_OVERDRIVE) |
498 | speed = SPEED_FLEXIBLE; |
499 | |
500 | speed &= 0xff; |
501 | |
502 | err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed); |
503 | if (err) |
504 | return err; |
505 | |
506 | return err; |
507 | } |
508 | #endif /* 0 */ |
509 | |
510 | static int ds_set_pullup(struct ds_device *dev, int delay) |
511 | { |
512 | int err = 0; |
513 | u8 del = 1 + (u8)(delay >> 4); |
514 | /* Just storing delay would not get the trunication and roundup. */ |
515 | int ms = del<<4; |
516 | |
517 | /* Enable spu_bit if a delay is set. */ |
518 | dev->spu_bit = delay ? COMM_SPU : 0; |
519 | /* If delay is zero, it has already been disabled, if the time is |
520 | * the same as the hardware was last programmed to, there is also |
521 | * nothing more to do. Compare with the recalculated value ms |
522 | * rather than del or delay which can have a different value. |
523 | */ |
524 | if (delay == 0 || ms == dev->spu_sleep) |
525 | return err; |
526 | |
527 | err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, index: del); |
528 | if (err) |
529 | return err; |
530 | |
531 | dev->spu_sleep = ms; |
532 | |
533 | return err; |
534 | } |
535 | |
536 | static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit) |
537 | { |
538 | int err; |
539 | struct ds_status st; |
540 | |
541 | err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0), |
542 | index: 0); |
543 | if (err) |
544 | return err; |
545 | |
546 | ds_wait_status(dev, st: &st); |
547 | |
548 | err = ds_recv_data(dev, buf: tbit, size: sizeof(*tbit)); |
549 | if (err < 0) |
550 | return err; |
551 | |
552 | return 0; |
553 | } |
554 | |
555 | #if 0 |
556 | static int ds_write_bit(struct ds_device *dev, u8 bit) |
557 | { |
558 | int err; |
559 | struct ds_status st; |
560 | |
561 | /* Set COMM_ICP to write without a readback. Note, this will |
562 | * produce one time slot, a down followed by an up with COMM_D |
563 | * only determing the timing. |
564 | */ |
565 | err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP | |
566 | (bit ? COMM_D : 0), 0); |
567 | if (err) |
568 | return err; |
569 | |
570 | ds_wait_status(dev, &st); |
571 | |
572 | return 0; |
573 | } |
574 | #endif |
575 | |
576 | static int ds_write_byte(struct ds_device *dev, u8 byte) |
577 | { |
578 | int err; |
579 | struct ds_status st; |
580 | |
581 | err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, index: byte); |
582 | if (err) |
583 | return err; |
584 | |
585 | if (dev->spu_bit) |
586 | msleep(msecs: dev->spu_sleep); |
587 | |
588 | err = ds_wait_status(dev, st: &st); |
589 | if (err) |
590 | return err; |
591 | |
592 | err = ds_recv_data(dev, buf: &dev->byte_buf, size: 1); |
593 | if (err < 0) |
594 | return err; |
595 | |
596 | return !(byte == dev->byte_buf); |
597 | } |
598 | |
599 | static int ds_read_byte(struct ds_device *dev, u8 *byte) |
600 | { |
601 | int err; |
602 | struct ds_status st; |
603 | |
604 | err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM, index: 0xff); |
605 | if (err) |
606 | return err; |
607 | |
608 | ds_wait_status(dev, st: &st); |
609 | |
610 | err = ds_recv_data(dev, buf: byte, size: sizeof(*byte)); |
611 | if (err < 0) |
612 | return err; |
613 | |
614 | return 0; |
615 | } |
616 | |
617 | static int ds_read_block(struct ds_device *dev, u8 *buf, int len) |
618 | { |
619 | struct ds_status st; |
620 | int err; |
621 | |
622 | if (len > 64*1024) |
623 | return -E2BIG; |
624 | |
625 | memset(buf, 0xFF, len); |
626 | |
627 | err = ds_send_data(dev, buf, len); |
628 | if (err < 0) |
629 | return err; |
630 | |
631 | err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM, index: len); |
632 | if (err) |
633 | return err; |
634 | |
635 | ds_wait_status(dev, st: &st); |
636 | |
637 | memset(buf, 0x00, len); |
638 | err = ds_recv_data(dev, buf, size: len); |
639 | |
640 | return err; |
641 | } |
642 | |
643 | static int ds_write_block(struct ds_device *dev, u8 *buf, int len) |
644 | { |
645 | int err; |
646 | struct ds_status st; |
647 | |
648 | err = ds_send_data(dev, buf, len); |
649 | if (err < 0) |
650 | return err; |
651 | |
652 | err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, index: len); |
653 | if (err) |
654 | return err; |
655 | |
656 | if (dev->spu_bit) |
657 | msleep(msecs: dev->spu_sleep); |
658 | |
659 | ds_wait_status(dev, st: &st); |
660 | |
661 | err = ds_recv_data(dev, buf, size: len); |
662 | if (err < 0) |
663 | return err; |
664 | |
665 | return !(err == len); |
666 | } |
667 | |
668 | static void ds9490r_search(void *data, struct w1_master *master, |
669 | u8 search_type, w1_slave_found_callback callback) |
670 | { |
671 | /* When starting with an existing id, the first id returned will |
672 | * be that device (if it is still on the bus most likely). |
673 | * |
674 | * If the number of devices found is less than or equal to the |
675 | * search_limit, that number of IDs will be returned. If there are |
676 | * more, search_limit IDs will be returned followed by a non-zero |
677 | * discrepency value. |
678 | */ |
679 | struct ds_device *dev = data; |
680 | int err; |
681 | u16 value, index; |
682 | struct ds_status st; |
683 | int search_limit; |
684 | int found = 0; |
685 | int i; |
686 | |
687 | /* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for |
688 | * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time. |
689 | */ |
690 | const unsigned long jtime = msecs_to_jiffies(m: 1000*8/75); |
691 | /* FIFO 128 bytes, bulk packet size 64, read a multiple of the |
692 | * packet size. |
693 | */ |
694 | const size_t bufsize = 2 * 64; |
695 | u64 *buf, *found_ids; |
696 | |
697 | buf = kmalloc(size: bufsize, GFP_KERNEL); |
698 | if (!buf) |
699 | return; |
700 | |
701 | /* |
702 | * We are holding the bus mutex during the scan, but adding devices via the |
703 | * callback needs the bus to be unlocked. So we queue up found ids here. |
704 | */ |
705 | found_ids = kmalloc_array(n: master->max_slave_count, size: sizeof(u64), GFP_KERNEL); |
706 | if (!found_ids) { |
707 | kfree(objp: buf); |
708 | return; |
709 | } |
710 | |
711 | mutex_lock(&master->bus_mutex); |
712 | |
713 | /* address to start searching at */ |
714 | if (ds_send_data(dev, buf: (u8 *)&master->search_id, len: 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(timeout: jtime); |
729 | |
730 | err = ds_recv_status(dev, st: &st); |
731 | if (err < 0 || err < sizeof(st)) |
732 | break; |
733 | |
734 | if (st.data_in_buffer_status) { |
735 | /* |
736 | * Bulk in can receive partial ids, but when it does |
737 | * they fail crc and will be discarded anyway. |
738 | * That has only been seen when status in buffer |
739 | * is 0 and bulk is read anyway, so don't read |
740 | * bulk without first checking if status says there |
741 | * is data to read. |
742 | */ |
743 | err = ds_recv_data(dev, buf: (u8 *)buf, size: bufsize); |
744 | if (err < 0) |
745 | break; |
746 | for (i = 0; i < err/8; ++i) { |
747 | found_ids[found++] = buf[i]; |
748 | /* |
749 | * can't know if there will be a discrepancy |
750 | * value after until the next id |
751 | */ |
752 | if (found == search_limit) { |
753 | master->search_id = buf[i]; |
754 | break; |
755 | } |
756 | } |
757 | } |
758 | |
759 | if (test_bit(W1_ABORT_SEARCH, &master->flags)) |
760 | break; |
761 | } while (!(st.status & (ST_IDLE | ST_HALT))); |
762 | |
763 | /* only continue the search if some weren't found */ |
764 | if (found <= search_limit) { |
765 | master->search_id = 0; |
766 | } else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) { |
767 | /* |
768 | * Only max_slave_count will be scanned in a search, |
769 | * but it will start where it left off next search |
770 | * until all ids are identified and then it will start |
771 | * over. A continued search will report the previous |
772 | * last id as the first id (provided it is still on the |
773 | * bus). |
774 | */ |
775 | dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, " |
776 | "will continue next search.\n" , __func__, |
777 | master->max_slave_count); |
778 | set_bit(nr: W1_WARN_MAX_COUNT, addr: &master->flags); |
779 | } |
780 | |
781 | search_out: |
782 | mutex_unlock(lock: &master->bus_mutex); |
783 | kfree(objp: buf); |
784 | |
785 | for (i = 0; i < found; i++) /* run callback for all queued up IDs */ |
786 | callback(master, found_ids[i]); |
787 | kfree(objp: found_ids); |
788 | } |
789 | |
790 | #if 0 |
791 | /* |
792 | * FIXME: if this disabled code is ever used in the future all ds_send_data() |
793 | * calls must be changed to use a DMAable buffer. |
794 | */ |
795 | static int ds_match_access(struct ds_device *dev, u64 init) |
796 | { |
797 | int err; |
798 | struct ds_status st; |
799 | |
800 | err = ds_send_data(dev, (unsigned char *)&init, sizeof(init)); |
801 | if (err) |
802 | return err; |
803 | |
804 | ds_wait_status(dev, &st); |
805 | |
806 | err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055); |
807 | if (err) |
808 | return err; |
809 | |
810 | ds_wait_status(dev, &st); |
811 | |
812 | return 0; |
813 | } |
814 | |
815 | static int ds_set_path(struct ds_device *dev, u64 init) |
816 | { |
817 | int err; |
818 | struct ds_status st; |
819 | u8 buf[9]; |
820 | |
821 | memcpy(buf, &init, 8); |
822 | buf[8] = BRANCH_MAIN; |
823 | |
824 | err = ds_send_data(dev, buf, sizeof(buf)); |
825 | if (err) |
826 | return err; |
827 | |
828 | ds_wait_status(dev, &st); |
829 | |
830 | err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0); |
831 | if (err) |
832 | return err; |
833 | |
834 | ds_wait_status(dev, &st); |
835 | |
836 | return 0; |
837 | } |
838 | |
839 | #endif /* 0 */ |
840 | |
841 | static u8 ds9490r_touch_bit(void *data, u8 bit) |
842 | { |
843 | struct ds_device *dev = data; |
844 | |
845 | if (ds_touch_bit(dev, bit, tbit: &dev->byte_buf)) |
846 | return 0; |
847 | |
848 | return dev->byte_buf; |
849 | } |
850 | |
851 | #if 0 |
852 | static void ds9490r_write_bit(void *data, u8 bit) |
853 | { |
854 | struct ds_device *dev = data; |
855 | |
856 | ds_write_bit(dev, bit); |
857 | } |
858 | |
859 | static u8 ds9490r_read_bit(void *data) |
860 | { |
861 | struct ds_device *dev = data; |
862 | int err; |
863 | |
864 | err = ds_touch_bit(dev, 1, &dev->byte_buf); |
865 | if (err) |
866 | return 0; |
867 | |
868 | return dev->byte_buf & 1; |
869 | } |
870 | #endif |
871 | |
872 | static void ds9490r_write_byte(void *data, u8 byte) |
873 | { |
874 | struct ds_device *dev = data; |
875 | |
876 | ds_write_byte(dev, byte); |
877 | } |
878 | |
879 | static u8 ds9490r_read_byte(void *data) |
880 | { |
881 | struct ds_device *dev = data; |
882 | int err; |
883 | |
884 | err = ds_read_byte(dev, byte: &dev->byte_buf); |
885 | if (err) |
886 | return 0; |
887 | |
888 | return dev->byte_buf; |
889 | } |
890 | |
891 | static void ds9490r_write_block(void *data, const u8 *buf, int len) |
892 | { |
893 | struct ds_device *dev = data; |
894 | u8 *tbuf; |
895 | |
896 | if (len <= 0) |
897 | return; |
898 | |
899 | tbuf = kmemdup(p: buf, size: len, GFP_KERNEL); |
900 | if (!tbuf) |
901 | return; |
902 | |
903 | ds_write_block(dev, buf: tbuf, len); |
904 | |
905 | kfree(objp: tbuf); |
906 | } |
907 | |
908 | static u8 ds9490r_read_block(void *data, u8 *buf, int len) |
909 | { |
910 | struct ds_device *dev = data; |
911 | int err; |
912 | u8 *tbuf; |
913 | |
914 | if (len <= 0) |
915 | return 0; |
916 | |
917 | tbuf = kmalloc(size: len, GFP_KERNEL); |
918 | if (!tbuf) |
919 | return 0; |
920 | |
921 | err = ds_read_block(dev, buf: tbuf, len); |
922 | if (err >= 0) |
923 | memcpy(buf, tbuf, len); |
924 | |
925 | kfree(objp: tbuf); |
926 | |
927 | return err >= 0 ? len : 0; |
928 | } |
929 | |
930 | static u8 ds9490r_reset(void *data) |
931 | { |
932 | struct ds_device *dev = data; |
933 | int err; |
934 | |
935 | err = ds_reset(dev); |
936 | if (err) |
937 | return 1; |
938 | |
939 | return 0; |
940 | } |
941 | |
942 | static u8 ds9490r_set_pullup(void *data, int delay) |
943 | { |
944 | struct ds_device *dev = data; |
945 | |
946 | if (ds_set_pullup(dev, delay)) |
947 | return 1; |
948 | |
949 | return 0; |
950 | } |
951 | |
952 | static int ds_w1_init(struct ds_device *dev) |
953 | { |
954 | memset(&dev->master, 0, sizeof(struct w1_bus_master)); |
955 | |
956 | /* Reset the device as it can be in a bad state. |
957 | * This is necessary because a block write will wait for data |
958 | * to be placed in the output buffer and block any later |
959 | * commands which will keep accumulating and the device will |
960 | * not be idle. Another case is removing the ds2490 module |
961 | * while a bus search is in progress, somehow a few commands |
962 | * get through, but the input transfers fail leaving data in |
963 | * the input buffer. This will cause the next read to fail |
964 | * see the note in ds_recv_data. |
965 | */ |
966 | ds_reset_device(dev); |
967 | |
968 | dev->master.data = dev; |
969 | dev->master.touch_bit = &ds9490r_touch_bit; |
970 | /* read_bit and write_bit in w1_bus_master are expected to set and |
971 | * sample the line level. For write_bit that means it is expected to |
972 | * set it to that value and leave it there. ds2490 only supports an |
973 | * individual time slot at the lowest level. The requirement from |
974 | * pulling the bus state down to reading the state is 15us, something |
975 | * that isn't realistic on the USB bus anyway. |
976 | dev->master.read_bit = &ds9490r_read_bit; |
977 | dev->master.write_bit = &ds9490r_write_bit; |
978 | */ |
979 | dev->master.read_byte = &ds9490r_read_byte; |
980 | dev->master.write_byte = &ds9490r_write_byte; |
981 | dev->master.read_block = &ds9490r_read_block; |
982 | dev->master.write_block = &ds9490r_write_block; |
983 | dev->master.reset_bus = &ds9490r_reset; |
984 | dev->master.set_pullup = &ds9490r_set_pullup; |
985 | dev->master.search = &ds9490r_search; |
986 | |
987 | return w1_add_master_device(master: &dev->master); |
988 | } |
989 | |
990 | static void ds_w1_fini(struct ds_device *dev) |
991 | { |
992 | w1_remove_master_device(master: &dev->master); |
993 | } |
994 | |
995 | static int ds_probe(struct usb_interface *intf, |
996 | const struct usb_device_id *udev_id) |
997 | { |
998 | struct usb_device *udev = interface_to_usbdev(intf); |
999 | struct usb_endpoint_descriptor *endpoint; |
1000 | struct usb_host_interface *iface_desc; |
1001 | struct ds_device *dev; |
1002 | int i, err, alt; |
1003 | |
1004 | dev = kzalloc(size: sizeof(struct ds_device), GFP_KERNEL); |
1005 | if (!dev) |
1006 | return -ENOMEM; |
1007 | |
1008 | dev->udev = usb_get_dev(dev: udev); |
1009 | if (!dev->udev) { |
1010 | err = -ENOMEM; |
1011 | goto err_out_free; |
1012 | } |
1013 | memset(dev->ep, 0, sizeof(dev->ep)); |
1014 | |
1015 | usb_set_intfdata(intf, data: dev); |
1016 | |
1017 | err = usb_reset_configuration(dev: dev->udev); |
1018 | if (err) { |
1019 | dev_err(&dev->udev->dev, |
1020 | "Failed to reset configuration: err=%d.\n" , err); |
1021 | goto err_out_clear; |
1022 | } |
1023 | |
1024 | /* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */ |
1025 | alt = 3; |
1026 | err = usb_set_interface(dev: dev->udev, |
1027 | ifnum: intf->cur_altsetting->desc.bInterfaceNumber, alternate: alt); |
1028 | if (err) { |
1029 | dev_err(&dev->udev->dev, "Failed to set alternative setting %d " |
1030 | "for %d interface: err=%d.\n" , alt, |
1031 | intf->cur_altsetting->desc.bInterfaceNumber, err); |
1032 | goto err_out_clear; |
1033 | } |
1034 | |
1035 | iface_desc = intf->cur_altsetting; |
1036 | if (iface_desc->desc.bNumEndpoints != NUM_EP-1) { |
1037 | dev_err(&dev->udev->dev, "Num endpoints=%d. It is not DS9490R.\n" , |
1038 | iface_desc->desc.bNumEndpoints); |
1039 | err = -EINVAL; |
1040 | goto err_out_clear; |
1041 | } |
1042 | |
1043 | /* |
1044 | * This loop doesn'd show control 0 endpoint, |
1045 | * so we will fill only 1-3 endpoints entry. |
1046 | */ |
1047 | for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { |
1048 | endpoint = &iface_desc->endpoint[i].desc; |
1049 | |
1050 | dev->ep[i+1] = endpoint->bEndpointAddress; |
1051 | #if 0 |
1052 | printk("%d: addr=%x, size=%d, dir=%s, type=%x\n" , |
1053 | i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize), |
1054 | (endpoint->bEndpointAddress & USB_DIR_IN)?"IN" :"OUT" , |
1055 | endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK); |
1056 | #endif |
1057 | } |
1058 | |
1059 | err = ds_w1_init(dev); |
1060 | if (err) |
1061 | goto err_out_clear; |
1062 | |
1063 | mutex_lock(&ds_mutex); |
1064 | list_add_tail(new: &dev->ds_entry, head: &ds_devices); |
1065 | mutex_unlock(lock: &ds_mutex); |
1066 | |
1067 | return 0; |
1068 | |
1069 | err_out_clear: |
1070 | usb_set_intfdata(intf, NULL); |
1071 | usb_put_dev(dev: dev->udev); |
1072 | err_out_free: |
1073 | kfree(objp: dev); |
1074 | return err; |
1075 | } |
1076 | |
1077 | static void ds_disconnect(struct usb_interface *intf) |
1078 | { |
1079 | struct ds_device *dev; |
1080 | |
1081 | dev = usb_get_intfdata(intf); |
1082 | if (!dev) |
1083 | return; |
1084 | |
1085 | mutex_lock(&ds_mutex); |
1086 | list_del(entry: &dev->ds_entry); |
1087 | mutex_unlock(lock: &ds_mutex); |
1088 | |
1089 | ds_w1_fini(dev); |
1090 | |
1091 | usb_set_intfdata(intf, NULL); |
1092 | |
1093 | usb_put_dev(dev: dev->udev); |
1094 | kfree(objp: dev); |
1095 | } |
1096 | |
1097 | static const struct usb_device_id ds_id_table[] = { |
1098 | { USB_DEVICE(0x04fa, 0x2490) }, |
1099 | { }, |
1100 | }; |
1101 | MODULE_DEVICE_TABLE(usb, ds_id_table); |
1102 | |
1103 | static struct usb_driver ds_driver = { |
1104 | .name = "DS9490R" , |
1105 | .probe = ds_probe, |
1106 | .disconnect = ds_disconnect, |
1107 | .id_table = ds_id_table, |
1108 | }; |
1109 | module_usb_driver(ds_driver); |
1110 | |
1111 | MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>" ); |
1112 | MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)" ); |
1113 | MODULE_LICENSE("GPL" ); |
1114 | |