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 | /* 1-wire data i/o fifo size, 128 bytes */ |
102 | #define FIFO_SIZE 0x80 |
103 | |
104 | /* Result Register flags */ |
105 | #define RR_DETECT 0xA5 /* New device detected */ |
106 | #define RR_NRS 0x01 /* Reset no presence or ... */ |
107 | #define RR_SH 0x02 /* short on reset or set path */ |
108 | #define RR_APP 0x04 /* alarming presence on reset */ |
109 | #define RR_VPP 0x08 /* 12V expected not seen */ |
110 | #define RR_CMP 0x10 /* compare error */ |
111 | #define RR_CRC 0x20 /* CRC error detected */ |
112 | #define RR_RDP 0x40 /* redirected page */ |
113 | #define RR_EOS 0x80 /* end of search error */ |
114 | |
115 | #define SPEED_NORMAL 0x00 |
116 | #define SPEED_FLEXIBLE 0x01 |
117 | #define SPEED_OVERDRIVE 0x02 |
118 | |
119 | #define NUM_EP 4 |
120 | #define EP_CONTROL 0 |
121 | #define EP_STATUS 1 |
122 | #define EP_DATA_OUT 2 |
123 | #define EP_DATA_IN 3 |
124 | |
125 | struct ds_device { |
126 | struct list_head ds_entry; |
127 | |
128 | struct usb_device *udev; |
129 | struct usb_interface *intf; |
130 | |
131 | int ep[NUM_EP]; |
132 | |
133 | /* Strong PullUp |
134 | * 0: pullup not active, else duration in milliseconds |
135 | */ |
136 | int spu_sleep; |
137 | /* spu_bit contains COMM_SPU or 0 depending on if the strong pullup |
138 | * should be active or not for writes. |
139 | */ |
140 | u16 spu_bit; |
141 | |
142 | u8 st_buf[ST_SIZE]; |
143 | u8 byte_buf; |
144 | |
145 | struct w1_bus_master master; |
146 | }; |
147 | |
148 | struct ds_status { |
149 | u8 enable; |
150 | u8 speed; |
151 | u8 pullup_dur; |
152 | u8 ppuls_dur; |
153 | u8 pulldown_slew; |
154 | u8 write1_time; |
155 | u8 write0_time; |
156 | u8 reserved0; |
157 | u8 status; |
158 | u8 command0; |
159 | u8 command1; |
160 | u8 command_buffer_status; |
161 | u8 data_out_buffer_status; |
162 | u8 data_in_buffer_status; |
163 | u8 reserved1; |
164 | u8 reserved2; |
165 | }; |
166 | |
167 | static LIST_HEAD(ds_devices); |
168 | static DEFINE_MUTEX(ds_mutex); |
169 | |
170 | static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index) |
171 | { |
172 | int err; |
173 | |
174 | err = usb_control_msg(dev: dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), |
175 | CONTROL_CMD, VENDOR, value, index, NULL, size: 0, timeout: 1000); |
176 | if (err < 0) { |
177 | dev_err(&dev->udev->dev, |
178 | "Failed to send command control message %x.%x: err=%d.\n" , |
179 | value, index, err); |
180 | return err; |
181 | } |
182 | |
183 | return err; |
184 | } |
185 | |
186 | static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index) |
187 | { |
188 | int err; |
189 | |
190 | err = usb_control_msg(dev: dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), |
191 | MODE_CMD, VENDOR, value, index, NULL, size: 0, timeout: 1000); |
192 | if (err < 0) { |
193 | dev_err(&dev->udev->dev, |
194 | "Failed to send mode control message %x.%x: err=%d.\n" , |
195 | value, index, err); |
196 | return err; |
197 | } |
198 | |
199 | return err; |
200 | } |
201 | |
202 | static int ds_send_control(struct ds_device *dev, u16 value, u16 index) |
203 | { |
204 | int err; |
205 | |
206 | err = usb_control_msg(dev: dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]), |
207 | COMM_CMD, VENDOR, value, index, NULL, size: 0, timeout: 1000); |
208 | if (err < 0) { |
209 | dev_err(&dev->udev->dev, |
210 | "Failed to send control message %x.%x: err=%d.\n" , |
211 | value, index, err); |
212 | return err; |
213 | } |
214 | |
215 | return err; |
216 | } |
217 | |
218 | static void ds_dump_status(struct ds_device *ds_dev, unsigned char *buf, int count) |
219 | { |
220 | struct device *dev = &ds_dev->udev->dev; |
221 | int i; |
222 | |
223 | dev_info(dev, "ep_status=0x%x, count=%d, status=%*phC" , |
224 | ds_dev->ep[EP_STATUS], count, count, buf); |
225 | |
226 | if (count >= 16) { |
227 | dev_dbg(dev, "enable flag: 0x%02x" , buf[0]); |
228 | dev_dbg(dev, "1-wire speed: 0x%02x" , buf[1]); |
229 | dev_dbg(dev, "strong pullup duration: 0x%02x" , buf[2]); |
230 | dev_dbg(dev, "programming pulse duration: 0x%02x" , buf[3]); |
231 | dev_dbg(dev, "pulldown slew rate control: 0x%02x" , buf[4]); |
232 | dev_dbg(dev, "write-1 low time: 0x%02x" , buf[5]); |
233 | dev_dbg(dev, "data sample offset/write-0 recovery time: 0x%02x" , buf[6]); |
234 | dev_dbg(dev, "reserved (test register): 0x%02x" , buf[7]); |
235 | dev_dbg(dev, "device status flags: 0x%02x" , buf[8]); |
236 | dev_dbg(dev, "communication command byte 1: 0x%02x" , buf[9]); |
237 | dev_dbg(dev, "communication command byte 2: 0x%02x" , buf[10]); |
238 | dev_dbg(dev, "communication command buffer status: 0x%02x" , buf[11]); |
239 | dev_dbg(dev, "1-wire data output buffer status: 0x%02x" , buf[12]); |
240 | dev_dbg(dev, "1-wire data input buffer status: 0x%02x" , buf[13]); |
241 | dev_dbg(dev, "reserved: 0x%02x" , buf[14]); |
242 | dev_dbg(dev, "reserved: 0x%02x" , buf[15]); |
243 | } |
244 | |
245 | for (i = 16; i < count; ++i) { |
246 | if (buf[i] == RR_DETECT) { |
247 | dev_dbg(dev, "New device detect.\n" ); |
248 | continue; |
249 | } |
250 | dev_dbg(dev, "Result Register Value: 0x%02x" , buf[i]); |
251 | if (buf[i] & RR_NRS) |
252 | dev_dbg(dev, "NRS: Reset no presence or ...\n" ); |
253 | if (buf[i] & RR_SH) |
254 | dev_dbg(dev, "SH: short on reset or set path\n" ); |
255 | if (buf[i] & RR_APP) |
256 | dev_dbg(dev, "APP: alarming presence on reset\n" ); |
257 | if (buf[i] & RR_VPP) |
258 | dev_dbg(dev, "VPP: 12V expected not seen\n" ); |
259 | if (buf[i] & RR_CMP) |
260 | dev_dbg(dev, "CMP: compare error\n" ); |
261 | if (buf[i] & RR_CRC) |
262 | dev_dbg(dev, "CRC: CRC error detected\n" ); |
263 | if (buf[i] & RR_RDP) |
264 | dev_dbg(dev, "RDP: redirected page\n" ); |
265 | if (buf[i] & RR_EOS) |
266 | dev_dbg(dev, "EOS: end of search error\n" ); |
267 | } |
268 | } |
269 | |
270 | static int ds_recv_status(struct ds_device *dev, struct ds_status *st) |
271 | { |
272 | int count, err; |
273 | |
274 | if (st) |
275 | memset(st, 0, sizeof(*st)); |
276 | |
277 | count = 0; |
278 | err = usb_interrupt_msg(usb_dev: dev->udev, |
279 | usb_rcvintpipe(dev->udev, |
280 | dev->ep[EP_STATUS]), |
281 | data: dev->st_buf, len: sizeof(dev->st_buf), |
282 | actual_length: &count, timeout: 1000); |
283 | if (err < 0) { |
284 | dev_err(&dev->udev->dev, |
285 | "Failed to read 1-wire data from 0x%x: err=%d.\n" , |
286 | dev->ep[EP_STATUS], err); |
287 | return err; |
288 | } |
289 | |
290 | if (st && count >= sizeof(*st)) |
291 | memcpy(st, dev->st_buf, sizeof(*st)); |
292 | |
293 | return count; |
294 | } |
295 | |
296 | static void ds_reset_device(struct ds_device *dev) |
297 | { |
298 | ds_send_control_cmd(dev, CTL_RESET_DEVICE, index: 0); |
299 | /* Always allow strong pullup which allow individual writes to use |
300 | * the strong pullup. |
301 | */ |
302 | if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE)) |
303 | dev_err(&dev->udev->dev, |
304 | "%s: Error allowing strong pullup\n" , __func__); |
305 | /* Chip strong pullup time was cleared. */ |
306 | if (dev->spu_sleep) { |
307 | /* lower 4 bits are 0, see ds_set_pullup */ |
308 | u8 del = dev->spu_sleep>>4; |
309 | |
310 | if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, index: del)) |
311 | dev_err(&dev->udev->dev, |
312 | "%s: Error setting duration\n" , __func__); |
313 | } |
314 | } |
315 | |
316 | static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size) |
317 | { |
318 | int count, err; |
319 | |
320 | /* Careful on size. If size is less than what is available in |
321 | * the input buffer, the device fails the bulk transfer and |
322 | * clears the input buffer. It could read the maximum size of |
323 | * the data buffer, but then do you return the first, last, or |
324 | * some set of the middle size bytes? As long as the rest of |
325 | * the code is correct there will be size bytes waiting. A |
326 | * call to ds_wait_status will wait until the device is idle |
327 | * and any data to be received would have been available. |
328 | */ |
329 | count = 0; |
330 | err = usb_bulk_msg(usb_dev: dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]), |
331 | data: buf, len: size, actual_length: &count, timeout: 1000); |
332 | if (err < 0) { |
333 | int recv_len; |
334 | |
335 | dev_info(&dev->udev->dev, "Clearing ep0x%x.\n" , dev->ep[EP_DATA_IN]); |
336 | usb_clear_halt(dev: dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN])); |
337 | |
338 | /* status might tell us why endpoint is stuck? */ |
339 | recv_len = ds_recv_status(dev, NULL); |
340 | if (recv_len >= 0) |
341 | ds_dump_status(ds_dev: dev, buf: dev->st_buf, count: recv_len); |
342 | |
343 | return err; |
344 | } |
345 | |
346 | #if 0 |
347 | { |
348 | int i; |
349 | |
350 | printk("%s: count=%d: " , __func__, count); |
351 | for (i = 0; i < count; ++i) |
352 | printk("%02x " , buf[i]); |
353 | printk("\n" ); |
354 | } |
355 | #endif |
356 | return count; |
357 | } |
358 | |
359 | static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len) |
360 | { |
361 | int count, err; |
362 | |
363 | count = 0; |
364 | 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); |
365 | if (err < 0) { |
366 | dev_err(&dev->udev->dev, "Failed to write 1-wire data to ep0x%x: " |
367 | "err=%d.\n" , dev->ep[EP_DATA_OUT], err); |
368 | return err; |
369 | } |
370 | |
371 | return err; |
372 | } |
373 | |
374 | #if 0 |
375 | |
376 | int ds_stop_pulse(struct ds_device *dev, int limit) |
377 | { |
378 | struct ds_status st; |
379 | int count = 0, err = 0; |
380 | |
381 | do { |
382 | err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0); |
383 | if (err) |
384 | break; |
385 | err = ds_send_control(dev, CTL_RESUME_EXE, 0); |
386 | if (err) |
387 | break; |
388 | err = ds_recv_status(dev, &st); |
389 | if (err) |
390 | break; |
391 | |
392 | if ((st.status & ST_SPUA) == 0) { |
393 | err = ds_send_control_mode(dev, MOD_PULSE_EN, 0); |
394 | if (err) |
395 | break; |
396 | } |
397 | } while (++count < limit); |
398 | |
399 | return err; |
400 | } |
401 | |
402 | int ds_detect(struct ds_device *dev, struct ds_status *st) |
403 | { |
404 | int err; |
405 | |
406 | err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0); |
407 | if (err) |
408 | return err; |
409 | |
410 | err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0); |
411 | if (err) |
412 | return err; |
413 | |
414 | err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40); |
415 | if (err) |
416 | return err; |
417 | |
418 | err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG); |
419 | if (err) |
420 | return err; |
421 | |
422 | err = ds_dump_status(dev, st); |
423 | |
424 | return err; |
425 | } |
426 | |
427 | #endif /* 0 */ |
428 | |
429 | static int ds_wait_status(struct ds_device *dev, struct ds_status *st) |
430 | { |
431 | int err, count = 0; |
432 | |
433 | do { |
434 | st->status = 0; |
435 | err = ds_recv_status(dev, st); |
436 | #if 0 |
437 | if (err >= 0) { |
438 | int i; |
439 | printk("0x%x: count=%d, status: " , dev->ep[EP_STATUS], err); |
440 | for (i = 0; i < err; ++i) |
441 | printk("%02x " , dev->st_buf[i]); |
442 | printk("\n" ); |
443 | } |
444 | #endif |
445 | } while (!(st->status & ST_IDLE) && !(err < 0) && ++count < 100); |
446 | |
447 | if (err >= 16 && st->status & ST_EPOF) { |
448 | dev_info(&dev->udev->dev, "Resetting device after ST_EPOF.\n" ); |
449 | ds_reset_device(dev); |
450 | /* Always dump the device status. */ |
451 | count = 101; |
452 | } |
453 | |
454 | /* Dump the status for errors or if there is extended return data. |
455 | * The extended status includes new device detection (maybe someone |
456 | * can do something with it). |
457 | */ |
458 | if (err > 16 || count >= 100 || err < 0) |
459 | ds_dump_status(ds_dev: dev, buf: dev->st_buf, count: err); |
460 | |
461 | /* Extended data isn't an error. Well, a short is, but the dump |
462 | * would have already told the user that and we can't do anything |
463 | * about it in software anyway. |
464 | */ |
465 | if (count >= 100 || err < 0) |
466 | return -1; |
467 | else |
468 | return 0; |
469 | } |
470 | |
471 | static int ds_reset(struct ds_device *dev) |
472 | { |
473 | int err; |
474 | |
475 | /* Other potentionally interesting flags for reset. |
476 | * |
477 | * COMM_NTF: Return result register feedback. This could be used to |
478 | * detect some conditions such as short, alarming presence, or |
479 | * detect if a new device was detected. |
480 | * |
481 | * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE: |
482 | * Select the data transfer rate. |
483 | */ |
484 | err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL); |
485 | if (err) |
486 | return err; |
487 | |
488 | return 0; |
489 | } |
490 | |
491 | #if 0 |
492 | static int ds_set_speed(struct ds_device *dev, int speed) |
493 | { |
494 | int err; |
495 | |
496 | if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE) |
497 | return -EINVAL; |
498 | |
499 | if (speed != SPEED_OVERDRIVE) |
500 | speed = SPEED_FLEXIBLE; |
501 | |
502 | speed &= 0xff; |
503 | |
504 | err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed); |
505 | if (err) |
506 | return err; |
507 | |
508 | return err; |
509 | } |
510 | #endif /* 0 */ |
511 | |
512 | static int ds_set_pullup(struct ds_device *dev, int delay) |
513 | { |
514 | int err = 0; |
515 | u8 del = 1 + (u8)(delay >> 4); |
516 | /* Just storing delay would not get the trunication and roundup. */ |
517 | int ms = del<<4; |
518 | |
519 | /* Enable spu_bit if a delay is set. */ |
520 | dev->spu_bit = delay ? COMM_SPU : 0; |
521 | /* If delay is zero, it has already been disabled, if the time is |
522 | * the same as the hardware was last programmed to, there is also |
523 | * nothing more to do. Compare with the recalculated value ms |
524 | * rather than del or delay which can have a different value. |
525 | */ |
526 | if (delay == 0 || ms == dev->spu_sleep) |
527 | return err; |
528 | |
529 | err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, index: del); |
530 | if (err) |
531 | return err; |
532 | |
533 | dev->spu_sleep = ms; |
534 | |
535 | return err; |
536 | } |
537 | |
538 | static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit) |
539 | { |
540 | int err; |
541 | struct ds_status st; |
542 | |
543 | err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0), |
544 | index: 0); |
545 | if (err) |
546 | return err; |
547 | |
548 | ds_wait_status(dev, st: &st); |
549 | |
550 | err = ds_recv_data(dev, buf: tbit, size: sizeof(*tbit)); |
551 | if (err < 0) |
552 | return err; |
553 | |
554 | return 0; |
555 | } |
556 | |
557 | #if 0 |
558 | static int ds_write_bit(struct ds_device *dev, u8 bit) |
559 | { |
560 | int err; |
561 | struct ds_status st; |
562 | |
563 | /* Set COMM_ICP to write without a readback. Note, this will |
564 | * produce one time slot, a down followed by an up with COMM_D |
565 | * only determing the timing. |
566 | */ |
567 | err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP | |
568 | (bit ? COMM_D : 0), 0); |
569 | if (err) |
570 | return err; |
571 | |
572 | ds_wait_status(dev, &st); |
573 | |
574 | return 0; |
575 | } |
576 | #endif |
577 | |
578 | static int ds_write_byte(struct ds_device *dev, u8 byte) |
579 | { |
580 | int err; |
581 | struct ds_status st; |
582 | |
583 | err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, index: byte); |
584 | if (err) |
585 | return err; |
586 | |
587 | if (dev->spu_bit) |
588 | msleep(msecs: dev->spu_sleep); |
589 | |
590 | err = ds_wait_status(dev, st: &st); |
591 | if (err) |
592 | return err; |
593 | |
594 | err = ds_recv_data(dev, buf: &dev->byte_buf, size: 1); |
595 | if (err < 0) |
596 | return err; |
597 | |
598 | return !(byte == dev->byte_buf); |
599 | } |
600 | |
601 | static int ds_read_byte(struct ds_device *dev, u8 *byte) |
602 | { |
603 | int err; |
604 | struct ds_status st; |
605 | |
606 | err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM, index: 0xff); |
607 | if (err) |
608 | return err; |
609 | |
610 | ds_wait_status(dev, st: &st); |
611 | |
612 | err = ds_recv_data(dev, buf: byte, size: sizeof(*byte)); |
613 | if (err < 0) |
614 | return err; |
615 | |
616 | return 0; |
617 | } |
618 | |
619 | static int read_block_chunk(struct ds_device *dev, u8 *buf, int len) |
620 | { |
621 | struct ds_status st; |
622 | int err; |
623 | |
624 | memset(buf, 0xFF, len); |
625 | |
626 | err = ds_send_data(dev, buf, len); |
627 | if (err < 0) |
628 | return err; |
629 | |
630 | err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM, index: len); |
631 | if (err) |
632 | return err; |
633 | |
634 | ds_wait_status(dev, st: &st); |
635 | |
636 | memset(buf, 0x00, len); |
637 | err = ds_recv_data(dev, buf, size: len); |
638 | |
639 | return err; |
640 | } |
641 | |
642 | static int ds_read_block(struct ds_device *dev, u8 *buf, int len) |
643 | { |
644 | int err, to_read, rem = len; |
645 | |
646 | if (len > 64 * 1024) |
647 | return -E2BIG; |
648 | |
649 | do { |
650 | to_read = rem <= FIFO_SIZE ? rem : FIFO_SIZE; |
651 | err = read_block_chunk(dev, buf: &buf[len - rem], len: to_read); |
652 | if (err < 0) |
653 | return err; |
654 | rem -= to_read; |
655 | } while (rem); |
656 | |
657 | return err; |
658 | } |
659 | |
660 | static int ds_write_block(struct ds_device *dev, u8 *buf, int len) |
661 | { |
662 | int err; |
663 | struct ds_status st; |
664 | |
665 | err = ds_send_data(dev, buf, len); |
666 | if (err < 0) |
667 | return err; |
668 | |
669 | err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, index: len); |
670 | if (err) |
671 | return err; |
672 | |
673 | if (dev->spu_bit) |
674 | msleep(msecs: dev->spu_sleep); |
675 | |
676 | ds_wait_status(dev, st: &st); |
677 | |
678 | err = ds_recv_data(dev, buf, size: len); |
679 | if (err < 0) |
680 | return err; |
681 | |
682 | return !(err == len); |
683 | } |
684 | |
685 | static void ds9490r_search(void *data, struct w1_master *master, |
686 | u8 search_type, w1_slave_found_callback callback) |
687 | { |
688 | /* When starting with an existing id, the first id returned will |
689 | * be that device (if it is still on the bus most likely). |
690 | * |
691 | * If the number of devices found is less than or equal to the |
692 | * search_limit, that number of IDs will be returned. If there are |
693 | * more, search_limit IDs will be returned followed by a non-zero |
694 | * discrepency value. |
695 | */ |
696 | struct ds_device *dev = data; |
697 | int err; |
698 | u16 value, index; |
699 | struct ds_status st; |
700 | int search_limit; |
701 | int found = 0; |
702 | int i; |
703 | |
704 | /* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for |
705 | * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time. |
706 | */ |
707 | const unsigned long jtime = msecs_to_jiffies(m: 1000*8/75); |
708 | /* FIFO 128 bytes, bulk packet size 64, read a multiple of the |
709 | * packet size. |
710 | */ |
711 | const size_t bufsize = 2 * 64; |
712 | u64 *buf, *found_ids; |
713 | |
714 | buf = kmalloc(size: bufsize, GFP_KERNEL); |
715 | if (!buf) |
716 | return; |
717 | |
718 | /* |
719 | * We are holding the bus mutex during the scan, but adding devices via the |
720 | * callback needs the bus to be unlocked. So we queue up found ids here. |
721 | */ |
722 | found_ids = kmalloc_array(n: master->max_slave_count, size: sizeof(u64), GFP_KERNEL); |
723 | if (!found_ids) { |
724 | kfree(objp: buf); |
725 | return; |
726 | } |
727 | |
728 | mutex_lock(&master->bus_mutex); |
729 | |
730 | /* address to start searching at */ |
731 | if (ds_send_data(dev, buf: (u8 *)&master->search_id, len: 8) < 0) |
732 | goto search_out; |
733 | master->search_id = 0; |
734 | |
735 | value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F | |
736 | COMM_RTS; |
737 | search_limit = master->max_slave_count; |
738 | if (search_limit > 255) |
739 | search_limit = 0; |
740 | index = search_type | (search_limit << 8); |
741 | if (ds_send_control(dev, value, index) < 0) |
742 | goto search_out; |
743 | |
744 | do { |
745 | schedule_timeout(timeout: jtime); |
746 | |
747 | err = ds_recv_status(dev, st: &st); |
748 | if (err < 0 || err < sizeof(st)) |
749 | break; |
750 | |
751 | if (st.data_in_buffer_status) { |
752 | /* |
753 | * Bulk in can receive partial ids, but when it does |
754 | * they fail crc and will be discarded anyway. |
755 | * That has only been seen when status in buffer |
756 | * is 0 and bulk is read anyway, so don't read |
757 | * bulk without first checking if status says there |
758 | * is data to read. |
759 | */ |
760 | err = ds_recv_data(dev, buf: (u8 *)buf, size: bufsize); |
761 | if (err < 0) |
762 | break; |
763 | for (i = 0; i < err/8; ++i) { |
764 | found_ids[found++] = buf[i]; |
765 | /* |
766 | * can't know if there will be a discrepancy |
767 | * value after until the next id |
768 | */ |
769 | if (found == search_limit) { |
770 | master->search_id = buf[i]; |
771 | break; |
772 | } |
773 | } |
774 | } |
775 | |
776 | if (test_bit(W1_ABORT_SEARCH, &master->flags)) |
777 | break; |
778 | } while (!(st.status & (ST_IDLE | ST_HALT))); |
779 | |
780 | /* only continue the search if some weren't found */ |
781 | if (found <= search_limit) { |
782 | master->search_id = 0; |
783 | } else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) { |
784 | /* |
785 | * Only max_slave_count will be scanned in a search, |
786 | * but it will start where it left off next search |
787 | * until all ids are identified and then it will start |
788 | * over. A continued search will report the previous |
789 | * last id as the first id (provided it is still on the |
790 | * bus). |
791 | */ |
792 | dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, " |
793 | "will continue next search.\n" , __func__, |
794 | master->max_slave_count); |
795 | set_bit(nr: W1_WARN_MAX_COUNT, addr: &master->flags); |
796 | } |
797 | |
798 | search_out: |
799 | mutex_unlock(lock: &master->bus_mutex); |
800 | kfree(objp: buf); |
801 | |
802 | for (i = 0; i < found; i++) /* run callback for all queued up IDs */ |
803 | callback(master, found_ids[i]); |
804 | kfree(objp: found_ids); |
805 | } |
806 | |
807 | #if 0 |
808 | /* |
809 | * FIXME: if this disabled code is ever used in the future all ds_send_data() |
810 | * calls must be changed to use a DMAable buffer. |
811 | */ |
812 | static int ds_match_access(struct ds_device *dev, u64 init) |
813 | { |
814 | int err; |
815 | struct ds_status st; |
816 | |
817 | err = ds_send_data(dev, (unsigned char *)&init, sizeof(init)); |
818 | if (err) |
819 | return err; |
820 | |
821 | ds_wait_status(dev, &st); |
822 | |
823 | err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055); |
824 | if (err) |
825 | return err; |
826 | |
827 | ds_wait_status(dev, &st); |
828 | |
829 | return 0; |
830 | } |
831 | |
832 | static int ds_set_path(struct ds_device *dev, u64 init) |
833 | { |
834 | int err; |
835 | struct ds_status st; |
836 | u8 buf[9]; |
837 | |
838 | memcpy(buf, &init, 8); |
839 | buf[8] = BRANCH_MAIN; |
840 | |
841 | err = ds_send_data(dev, buf, sizeof(buf)); |
842 | if (err) |
843 | return err; |
844 | |
845 | ds_wait_status(dev, &st); |
846 | |
847 | err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0); |
848 | if (err) |
849 | return err; |
850 | |
851 | ds_wait_status(dev, &st); |
852 | |
853 | return 0; |
854 | } |
855 | |
856 | #endif /* 0 */ |
857 | |
858 | static u8 ds9490r_touch_bit(void *data, u8 bit) |
859 | { |
860 | struct ds_device *dev = data; |
861 | |
862 | if (ds_touch_bit(dev, bit, tbit: &dev->byte_buf)) |
863 | return 0; |
864 | |
865 | return dev->byte_buf; |
866 | } |
867 | |
868 | #if 0 |
869 | static void ds9490r_write_bit(void *data, u8 bit) |
870 | { |
871 | struct ds_device *dev = data; |
872 | |
873 | ds_write_bit(dev, bit); |
874 | } |
875 | |
876 | static u8 ds9490r_read_bit(void *data) |
877 | { |
878 | struct ds_device *dev = data; |
879 | int err; |
880 | |
881 | err = ds_touch_bit(dev, 1, &dev->byte_buf); |
882 | if (err) |
883 | return 0; |
884 | |
885 | return dev->byte_buf & 1; |
886 | } |
887 | #endif |
888 | |
889 | static void ds9490r_write_byte(void *data, u8 byte) |
890 | { |
891 | struct ds_device *dev = data; |
892 | |
893 | ds_write_byte(dev, byte); |
894 | } |
895 | |
896 | static u8 ds9490r_read_byte(void *data) |
897 | { |
898 | struct ds_device *dev = data; |
899 | int err; |
900 | |
901 | err = ds_read_byte(dev, byte: &dev->byte_buf); |
902 | if (err) |
903 | return 0; |
904 | |
905 | return dev->byte_buf; |
906 | } |
907 | |
908 | static void ds9490r_write_block(void *data, const u8 *buf, int len) |
909 | { |
910 | struct ds_device *dev = data; |
911 | u8 *tbuf; |
912 | |
913 | if (len <= 0) |
914 | return; |
915 | |
916 | tbuf = kmemdup(p: buf, size: len, GFP_KERNEL); |
917 | if (!tbuf) |
918 | return; |
919 | |
920 | ds_write_block(dev, buf: tbuf, len); |
921 | |
922 | kfree(objp: tbuf); |
923 | } |
924 | |
925 | static u8 ds9490r_read_block(void *data, u8 *buf, int len) |
926 | { |
927 | struct ds_device *dev = data; |
928 | int err; |
929 | u8 *tbuf; |
930 | |
931 | if (len <= 0) |
932 | return 0; |
933 | |
934 | tbuf = kmalloc(size: len, GFP_KERNEL); |
935 | if (!tbuf) |
936 | return 0; |
937 | |
938 | err = ds_read_block(dev, buf: tbuf, len); |
939 | if (err >= 0) |
940 | memcpy(buf, tbuf, len); |
941 | |
942 | kfree(objp: tbuf); |
943 | |
944 | return err >= 0 ? len : 0; |
945 | } |
946 | |
947 | static u8 ds9490r_reset(void *data) |
948 | { |
949 | struct ds_device *dev = data; |
950 | int err; |
951 | |
952 | err = ds_reset(dev); |
953 | if (err) |
954 | return 1; |
955 | |
956 | return 0; |
957 | } |
958 | |
959 | static u8 ds9490r_set_pullup(void *data, int delay) |
960 | { |
961 | struct ds_device *dev = data; |
962 | |
963 | if (ds_set_pullup(dev, delay)) |
964 | return 1; |
965 | |
966 | return 0; |
967 | } |
968 | |
969 | static int ds_w1_init(struct ds_device *dev) |
970 | { |
971 | memset(&dev->master, 0, sizeof(struct w1_bus_master)); |
972 | |
973 | /* Reset the device as it can be in a bad state. |
974 | * This is necessary because a block write will wait for data |
975 | * to be placed in the output buffer and block any later |
976 | * commands which will keep accumulating and the device will |
977 | * not be idle. Another case is removing the ds2490 module |
978 | * while a bus search is in progress, somehow a few commands |
979 | * get through, but the input transfers fail leaving data in |
980 | * the input buffer. This will cause the next read to fail |
981 | * see the note in ds_recv_data. |
982 | */ |
983 | ds_reset_device(dev); |
984 | |
985 | dev->master.data = dev; |
986 | dev->master.touch_bit = &ds9490r_touch_bit; |
987 | /* read_bit and write_bit in w1_bus_master are expected to set and |
988 | * sample the line level. For write_bit that means it is expected to |
989 | * set it to that value and leave it there. ds2490 only supports an |
990 | * individual time slot at the lowest level. The requirement from |
991 | * pulling the bus state down to reading the state is 15us, something |
992 | * that isn't realistic on the USB bus anyway. |
993 | dev->master.read_bit = &ds9490r_read_bit; |
994 | dev->master.write_bit = &ds9490r_write_bit; |
995 | */ |
996 | dev->master.read_byte = &ds9490r_read_byte; |
997 | dev->master.write_byte = &ds9490r_write_byte; |
998 | dev->master.read_block = &ds9490r_read_block; |
999 | dev->master.write_block = &ds9490r_write_block; |
1000 | dev->master.reset_bus = &ds9490r_reset; |
1001 | dev->master.set_pullup = &ds9490r_set_pullup; |
1002 | dev->master.search = &ds9490r_search; |
1003 | |
1004 | return w1_add_master_device(master: &dev->master); |
1005 | } |
1006 | |
1007 | static void ds_w1_fini(struct ds_device *dev) |
1008 | { |
1009 | w1_remove_master_device(master: &dev->master); |
1010 | } |
1011 | |
1012 | static int ds_probe(struct usb_interface *intf, |
1013 | const struct usb_device_id *udev_id) |
1014 | { |
1015 | struct usb_device *udev = interface_to_usbdev(intf); |
1016 | struct usb_endpoint_descriptor *endpoint; |
1017 | struct usb_host_interface *iface_desc; |
1018 | struct ds_device *dev; |
1019 | int i, err, alt; |
1020 | |
1021 | dev = kzalloc(size: sizeof(struct ds_device), GFP_KERNEL); |
1022 | if (!dev) |
1023 | return -ENOMEM; |
1024 | |
1025 | dev->udev = usb_get_dev(dev: udev); |
1026 | if (!dev->udev) { |
1027 | err = -ENOMEM; |
1028 | goto err_out_free; |
1029 | } |
1030 | memset(dev->ep, 0, sizeof(dev->ep)); |
1031 | |
1032 | usb_set_intfdata(intf, data: dev); |
1033 | |
1034 | err = usb_reset_configuration(dev: dev->udev); |
1035 | if (err) { |
1036 | dev_err(&dev->udev->dev, |
1037 | "Failed to reset configuration: err=%d.\n" , err); |
1038 | goto err_out_clear; |
1039 | } |
1040 | |
1041 | /* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */ |
1042 | alt = 3; |
1043 | err = usb_set_interface(dev: dev->udev, |
1044 | ifnum: intf->cur_altsetting->desc.bInterfaceNumber, alternate: alt); |
1045 | if (err) { |
1046 | dev_err(&dev->udev->dev, "Failed to set alternative setting %d " |
1047 | "for %d interface: err=%d.\n" , alt, |
1048 | intf->cur_altsetting->desc.bInterfaceNumber, err); |
1049 | goto err_out_clear; |
1050 | } |
1051 | |
1052 | iface_desc = intf->cur_altsetting; |
1053 | if (iface_desc->desc.bNumEndpoints != NUM_EP-1) { |
1054 | dev_err(&dev->udev->dev, "Num endpoints=%d. It is not DS9490R.\n" , |
1055 | iface_desc->desc.bNumEndpoints); |
1056 | err = -EINVAL; |
1057 | goto err_out_clear; |
1058 | } |
1059 | |
1060 | /* |
1061 | * This loop doesn'd show control 0 endpoint, |
1062 | * so we will fill only 1-3 endpoints entry. |
1063 | */ |
1064 | for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { |
1065 | endpoint = &iface_desc->endpoint[i].desc; |
1066 | |
1067 | dev->ep[i+1] = endpoint->bEndpointAddress; |
1068 | #if 0 |
1069 | printk("%d: addr=%x, size=%d, dir=%s, type=%x\n" , |
1070 | i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize), |
1071 | (endpoint->bEndpointAddress & USB_DIR_IN)?"IN" :"OUT" , |
1072 | endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK); |
1073 | #endif |
1074 | } |
1075 | |
1076 | err = ds_w1_init(dev); |
1077 | if (err) |
1078 | goto err_out_clear; |
1079 | |
1080 | mutex_lock(&ds_mutex); |
1081 | list_add_tail(new: &dev->ds_entry, head: &ds_devices); |
1082 | mutex_unlock(lock: &ds_mutex); |
1083 | |
1084 | return 0; |
1085 | |
1086 | err_out_clear: |
1087 | usb_set_intfdata(intf, NULL); |
1088 | usb_put_dev(dev: dev->udev); |
1089 | err_out_free: |
1090 | kfree(objp: dev); |
1091 | return err; |
1092 | } |
1093 | |
1094 | static void ds_disconnect(struct usb_interface *intf) |
1095 | { |
1096 | struct ds_device *dev; |
1097 | |
1098 | dev = usb_get_intfdata(intf); |
1099 | if (!dev) |
1100 | return; |
1101 | |
1102 | mutex_lock(&ds_mutex); |
1103 | list_del(entry: &dev->ds_entry); |
1104 | mutex_unlock(lock: &ds_mutex); |
1105 | |
1106 | ds_w1_fini(dev); |
1107 | |
1108 | usb_set_intfdata(intf, NULL); |
1109 | |
1110 | usb_put_dev(dev: dev->udev); |
1111 | kfree(objp: dev); |
1112 | } |
1113 | |
1114 | static const struct usb_device_id ds_id_table[] = { |
1115 | { USB_DEVICE(0x04fa, 0x2490) }, |
1116 | { }, |
1117 | }; |
1118 | MODULE_DEVICE_TABLE(usb, ds_id_table); |
1119 | |
1120 | static struct usb_driver ds_driver = { |
1121 | .name = "DS9490R" , |
1122 | .probe = ds_probe, |
1123 | .disconnect = ds_disconnect, |
1124 | .id_table = ds_id_table, |
1125 | }; |
1126 | module_usb_driver(ds_driver); |
1127 | |
1128 | MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>" ); |
1129 | MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)" ); |
1130 | MODULE_LICENSE("GPL" ); |
1131 | |