1/*
2 *	ds2490.c  USB to one wire bridge
3 *
4 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
5 *
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/mod_devicetable.h>
25#include <linux/usb.h>
26#include <linux/slab.h>
27
28#include "../w1_int.h"
29#include "../w1.h"
30
31/* USB Standard */
32/* USB Control request vendor type */
33#define VENDOR				0x40
34
35/* COMMAND TYPE CODES */
36#define CONTROL_CMD			0x00
37#define COMM_CMD			0x01
38#define MODE_CMD			0x02
39
40/* CONTROL COMMAND CODES */
41#define CTL_RESET_DEVICE		0x0000
42#define CTL_START_EXE			0x0001
43#define CTL_RESUME_EXE			0x0002
44#define CTL_HALT_EXE_IDLE		0x0003
45#define CTL_HALT_EXE_DONE		0x0004
46#define CTL_FLUSH_COMM_CMDS		0x0007
47#define CTL_FLUSH_RCV_BUFFER		0x0008
48#define CTL_FLUSH_XMT_BUFFER		0x0009
49#define CTL_GET_COMM_CMDS		0x000A
50
51/* MODE COMMAND CODES */
52#define MOD_PULSE_EN			0x0000
53#define MOD_SPEED_CHANGE_EN		0x0001
54#define MOD_1WIRE_SPEED			0x0002
55#define MOD_STRONG_PU_DURATION		0x0003
56#define MOD_PULLDOWN_SLEWRATE		0x0004
57#define MOD_PROG_PULSE_DURATION		0x0005
58#define MOD_WRITE1_LOWTIME		0x0006
59#define MOD_DSOW0_TREC			0x0007
60
61/* COMMUNICATION COMMAND CODES */
62#define COMM_ERROR_ESCAPE		0x0601
63#define COMM_SET_DURATION		0x0012
64#define COMM_BIT_IO			0x0020
65#define COMM_PULSE			0x0030
66#define COMM_1_WIRE_RESET		0x0042
67#define COMM_BYTE_IO			0x0052
68#define COMM_MATCH_ACCESS		0x0064
69#define COMM_BLOCK_IO			0x0074
70#define COMM_READ_STRAIGHT		0x0080
71#define COMM_DO_RELEASE			0x6092
72#define COMM_SET_PATH			0x00A2
73#define COMM_WRITE_SRAM_PAGE		0x00B2
74#define COMM_WRITE_EPROM		0x00C4
75#define COMM_READ_CRC_PROT_PAGE		0x00D4
76#define COMM_READ_REDIRECT_PAGE_CRC	0x21E4
77#define COMM_SEARCH_ACCESS		0x00F4
78
79/* Communication command bits */
80#define COMM_TYPE			0x0008
81#define COMM_SE				0x0008
82#define COMM_D				0x0008
83#define COMM_Z				0x0008
84#define COMM_CH				0x0008
85#define COMM_SM				0x0008
86#define COMM_R				0x0008
87#define COMM_IM				0x0001
88
89#define COMM_PS				0x4000
90#define COMM_PST			0x4000
91#define COMM_CIB			0x4000
92#define COMM_RTS			0x4000
93#define COMM_DT				0x2000
94#define COMM_SPU			0x1000
95#define COMM_F				0x0800
96#define COMM_NTF			0x0400
97#define COMM_ICP			0x0200
98#define COMM_RST			0x0100
99
100#define PULSE_PROG			0x01
101#define PULSE_SPUE			0x02
102
103#define BRANCH_MAIN			0xCC
104#define BRANCH_AUX			0x33
105
106/* Status flags */
107#define ST_SPUA				0x01  /* Strong Pull-up is active */
108#define ST_PRGA				0x02  /* 12V programming pulse is being generated */
109#define ST_12VP				0x04  /* external 12V programming voltage is present */
110#define ST_PMOD				0x08  /* DS2490 powered from USB and external sources */
111#define ST_HALT				0x10  /* DS2490 is currently halted */
112#define ST_IDLE				0x20  /* DS2490 is currently idle */
113#define ST_EPOF				0x80
114/* Status transfer size, 16 bytes status, 16 byte result flags */
115#define ST_SIZE				0x20
116
117/* Result Register flags */
118#define RR_DETECT			0xA5 /* New device detected */
119#define RR_NRS				0x01 /* Reset no presence or ... */
120#define RR_SH				0x02 /* short on reset or set path */
121#define RR_APP				0x04 /* alarming presence on reset */
122#define RR_VPP				0x08 /* 12V expected not seen */
123#define RR_CMP				0x10 /* compare error */
124#define RR_CRC				0x20 /* CRC error detected */
125#define RR_RDP				0x40 /* redirected page */
126#define RR_EOS				0x80 /* end of search error */
127
128#define SPEED_NORMAL			0x00
129#define SPEED_FLEXIBLE			0x01
130#define SPEED_OVERDRIVE			0x02
131
132#define NUM_EP				4
133#define EP_CONTROL			0
134#define EP_STATUS			1
135#define EP_DATA_OUT			2
136#define EP_DATA_IN			3
137
138struct ds_device
139{
140	struct list_head	ds_entry;
141
142	struct usb_device	*udev;
143	struct usb_interface	*intf;
144
145	int			ep[NUM_EP];
146
147	/* Strong PullUp
148	 * 0: pullup not active, else duration in milliseconds
149	 */
150	int			spu_sleep;
151	/* spu_bit contains COMM_SPU or 0 depending on if the strong pullup
152	 * should be active or not for writes.
153	 */
154	u16			spu_bit;
155
156	struct w1_bus_master	master;
157};
158
159struct ds_status
160{
161	u8			enable;
162	u8			speed;
163	u8			pullup_dur;
164	u8			ppuls_dur;
165	u8			pulldown_slew;
166	u8			write1_time;
167	u8			write0_time;
168	u8			reserved0;
169	u8			status;
170	u8			command0;
171	u8			command1;
172	u8			command_buffer_status;
173	u8			data_out_buffer_status;
174	u8			data_in_buffer_status;
175	u8			reserved1;
176	u8			reserved2;
177
178};
179
180static struct usb_device_id ds_id_table [] = {
181	{ USB_DEVICE(0x04fa, 0x2490) },
182	{ },
183};
184MODULE_DEVICE_TABLE(usb, ds_id_table);
185
186static int ds_probe(struct usb_interface *, const struct usb_device_id *);
187static void ds_disconnect(struct usb_interface *);
188
189static int ds_send_control(struct ds_device *, u16, u16);
190static int ds_send_control_cmd(struct ds_device *, u16, u16);
191
192static LIST_HEAD(ds_devices);
193static DEFINE_MUTEX(ds_mutex);
194
195static struct usb_driver ds_driver = {
196	.name =		"DS9490R",
197	.probe =	ds_probe,
198	.disconnect =	ds_disconnect,
199	.id_table =	ds_id_table,
200};
201
202static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index)
203{
204	int err;
205
206	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
207			CONTROL_CMD, VENDOR, value, index, NULL, 0, 1000);
208	if (err < 0) {
209		pr_err("Failed to send command control message %x.%x: err=%d.\n",
210				value, index, err);
211		return err;
212	}
213
214	return err;
215}
216
217static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index)
218{
219	int err;
220
221	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
222			MODE_CMD, VENDOR, value, index, NULL, 0, 1000);
223	if (err < 0) {
224		pr_err("Failed to send mode control message %x.%x: err=%d.\n",
225				value, index, err);
226		return err;
227	}
228
229	return err;
230}
231
232static int ds_send_control(struct ds_device *dev, u16 value, u16 index)
233{
234	int err;
235
236	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
237			COMM_CMD, VENDOR, value, index, NULL, 0, 1000);
238	if (err < 0) {
239		pr_err("Failed to send control message %x.%x: err=%d.\n",
240				value, index, err);
241		return err;
242	}
243
244	return err;
245}
246
247static int ds_recv_status_nodump(struct ds_device *dev, struct ds_status *st,
248				 unsigned char *buf, int size)
249{
250	int count, err;
251
252	memset(st, 0, sizeof(*st));
253
254	count = 0;
255	err = usb_interrupt_msg(dev->udev, usb_rcvintpipe(dev->udev,
256		dev->ep[EP_STATUS]), buf, size, &count, 1000);
257	if (err < 0) {
258		pr_err("Failed to read 1-wire data from 0x%x: err=%d.\n",
259		       dev->ep[EP_STATUS], err);
260		return err;
261	}
262
263	if (count >= sizeof(*st))
264		memcpy(st, buf, sizeof(*st));
265
266	return count;
267}
268
269static inline void ds_print_msg(unsigned char *buf, unsigned char *str, int off)
270{
271	pr_info("%45s: %8x\n", str, buf[off]);
272}
273
274static void ds_dump_status(struct ds_device *dev, unsigned char *buf, int count)
275{
276	int i;
277
278	pr_info("0x%x: count=%d, status: ", dev->ep[EP_STATUS], count);
279	for (i=0; i<count; ++i)
280		pr_info("%02x ", buf[i]);
281	pr_info("\n");
282
283	if (count >= 16) {
284		ds_print_msg(buf, "enable flag", 0);
285		ds_print_msg(buf, "1-wire speed", 1);
286		ds_print_msg(buf, "strong pullup duration", 2);
287		ds_print_msg(buf, "programming pulse duration", 3);
288		ds_print_msg(buf, "pulldown slew rate control", 4);
289		ds_print_msg(buf, "write-1 low time", 5);
290		ds_print_msg(buf, "data sample offset/write-0 recovery time",
291			6);
292		ds_print_msg(buf, "reserved (test register)", 7);
293		ds_print_msg(buf, "device status flags", 8);
294		ds_print_msg(buf, "communication command byte 1", 9);
295		ds_print_msg(buf, "communication command byte 2", 10);
296		ds_print_msg(buf, "communication command buffer status", 11);
297		ds_print_msg(buf, "1-wire data output buffer status", 12);
298		ds_print_msg(buf, "1-wire data input buffer status", 13);
299		ds_print_msg(buf, "reserved", 14);
300		ds_print_msg(buf, "reserved", 15);
301	}
302	for (i = 16; i < count; ++i) {
303		if (buf[i] == RR_DETECT) {
304			ds_print_msg(buf, "new device detect", i);
305			continue;
306		}
307		ds_print_msg(buf, "Result Register Value: ", i);
308		if (buf[i] & RR_NRS)
309			pr_info("NRS: Reset no presence or ...\n");
310		if (buf[i] & RR_SH)
311			pr_info("SH: short on reset or set path\n");
312		if (buf[i] & RR_APP)
313			pr_info("APP: alarming presence on reset\n");
314		if (buf[i] & RR_VPP)
315			pr_info("VPP: 12V expected not seen\n");
316		if (buf[i] & RR_CMP)
317			pr_info("CMP: compare error\n");
318		if (buf[i] & RR_CRC)
319			pr_info("CRC: CRC error detected\n");
320		if (buf[i] & RR_RDP)
321			pr_info("RDP: redirected page\n");
322		if (buf[i] & RR_EOS)
323			pr_info("EOS: end of search error\n");
324	}
325}
326
327static void ds_reset_device(struct ds_device *dev)
328{
329	ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
330	/* Always allow strong pullup which allow individual writes to use
331	 * the strong pullup.
332	 */
333	if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE))
334		pr_err("ds_reset_device: Error allowing strong pullup\n");
335	/* Chip strong pullup time was cleared. */
336	if (dev->spu_sleep) {
337		/* lower 4 bits are 0, see ds_set_pullup */
338		u8 del = dev->spu_sleep>>4;
339		if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del))
340			pr_err("ds_reset_device: Error setting duration\n");
341	}
342}
343
344static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
345{
346	int count, err;
347	struct ds_status st;
348
349	/* Careful on size.  If size is less than what is available in
350	 * the input buffer, the device fails the bulk transfer and
351	 * clears the input buffer.  It could read the maximum size of
352	 * the data buffer, but then do you return the first, last, or
353	 * some set of the middle size bytes?  As long as the rest of
354	 * the code is correct there will be size bytes waiting.  A
355	 * call to ds_wait_status will wait until the device is idle
356	 * and any data to be received would have been available.
357	 */
358	count = 0;
359	err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
360				buf, size, &count, 1000);
361	if (err < 0) {
362		u8 buf[ST_SIZE];
363		int count;
364
365		pr_info("Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]);
366		usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
367
368		count = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
369		ds_dump_status(dev, buf, count);
370		return err;
371	}
372
373#if 0
374	{
375		int i;
376
377		printk("%s: count=%d: ", __func__, count);
378		for (i=0; i<count; ++i)
379			printk("%02x ", buf[i]);
380		printk("\n");
381	}
382#endif
383	return count;
384}
385
386static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len)
387{
388	int count, err;
389
390	count = 0;
391	err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), buf, len, &count, 1000);
392	if (err < 0) {
393		pr_err("Failed to write 1-wire data to ep0x%x: "
394			"err=%d.\n", dev->ep[EP_DATA_OUT], err);
395		return err;
396	}
397
398	return err;
399}
400
401#if 0
402
403int ds_stop_pulse(struct ds_device *dev, int limit)
404{
405	struct ds_status st;
406	int count = 0, err = 0;
407	u8 buf[ST_SIZE];
408
409	do {
410		err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0);
411		if (err)
412			break;
413		err = ds_send_control(dev, CTL_RESUME_EXE, 0);
414		if (err)
415			break;
416		err = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
417		if (err)
418			break;
419
420		if ((st.status & ST_SPUA) == 0) {
421			err = ds_send_control_mode(dev, MOD_PULSE_EN, 0);
422			if (err)
423				break;
424		}
425	} while(++count < limit);
426
427	return err;
428}
429
430int ds_detect(struct ds_device *dev, struct ds_status *st)
431{
432	int err;
433
434	err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
435	if (err)
436		return err;
437
438	err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0);
439	if (err)
440		return err;
441
442	err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40);
443	if (err)
444		return err;
445
446	err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG);
447	if (err)
448		return err;
449
450	err = ds_dump_status(dev, st);
451
452	return err;
453}
454
455#endif  /*  0  */
456
457static int ds_wait_status(struct ds_device *dev, struct ds_status *st)
458{
459	u8 buf[ST_SIZE];
460	int err, count = 0;
461
462	do {
463		st->status = 0;
464		err = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
465#if 0
466		if (err >= 0) {
467			int i;
468			printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err);
469			for (i=0; i<err; ++i)
470				printk("%02x ", buf[i]);
471			printk("\n");
472		}
473#endif
474	} while (!(st->status & ST_IDLE) && !(err < 0) && ++count < 100);
475
476	if (err >= 16 && st->status & ST_EPOF) {
477		pr_info("Resetting device after ST_EPOF.\n");
478		ds_reset_device(dev);
479		/* Always dump the device status. */
480		count = 101;
481	}
482
483	/* Dump the status for errors or if there is extended return data.
484	 * The extended status includes new device detection (maybe someone
485	 * can do something with it).
486	 */
487	if (err > 16 || count >= 100 || err < 0)
488		ds_dump_status(dev, buf, err);
489
490	/* Extended data isn't an error.  Well, a short is, but the dump
491	 * would have already told the user that and we can't do anything
492	 * about it in software anyway.
493	 */
494	if (count >= 100 || err < 0)
495		return -1;
496	else
497		return 0;
498}
499
500static int ds_reset(struct ds_device *dev)
501{
502	int err;
503
504	/* Other potentionally interesting flags for reset.
505	 *
506	 * COMM_NTF: Return result register feedback.  This could be used to
507	 * detect some conditions such as short, alarming presence, or
508	 * detect if a new device was detected.
509	 *
510	 * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE:
511	 * Select the data transfer rate.
512	 */
513	err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL);
514	if (err)
515		return err;
516
517	return 0;
518}
519
520#if 0
521static int ds_set_speed(struct ds_device *dev, int speed)
522{
523	int err;
524
525	if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE)
526		return -EINVAL;
527
528	if (speed != SPEED_OVERDRIVE)
529		speed = SPEED_FLEXIBLE;
530
531	speed &= 0xff;
532
533	err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed);
534	if (err)
535		return err;
536
537	return err;
538}
539#endif  /*  0  */
540
541static int ds_set_pullup(struct ds_device *dev, int delay)
542{
543	int err = 0;
544	u8 del = 1 + (u8)(delay >> 4);
545	/* Just storing delay would not get the trunication and roundup. */
546	int ms = del<<4;
547
548	/* Enable spu_bit if a delay is set. */
549	dev->spu_bit = delay ? COMM_SPU : 0;
550	/* If delay is zero, it has already been disabled, if the time is
551	 * the same as the hardware was last programmed to, there is also
552	 * nothing more to do.  Compare with the recalculated value ms
553	 * rather than del or delay which can have a different value.
554	 */
555	if (delay == 0 || ms == dev->spu_sleep)
556		return err;
557
558	err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del);
559	if (err)
560		return err;
561
562	dev->spu_sleep = ms;
563
564	return err;
565}
566
567static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit)
568{
569	int err;
570	struct ds_status st;
571
572	err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0),
573		0);
574	if (err)
575		return err;
576
577	ds_wait_status(dev, &st);
578
579	err = ds_recv_data(dev, tbit, sizeof(*tbit));
580	if (err < 0)
581		return err;
582
583	return 0;
584}
585
586#if 0
587static int ds_write_bit(struct ds_device *dev, u8 bit)
588{
589	int err;
590	struct ds_status st;
591
592	/* Set COMM_ICP to write without a readback.  Note, this will
593	 * produce one time slot, a down followed by an up with COMM_D
594	 * only determing the timing.
595	 */
596	err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP |
597		(bit ? COMM_D : 0), 0);
598	if (err)
599		return err;
600
601	ds_wait_status(dev, &st);
602
603	return 0;
604}
605#endif
606
607static int ds_write_byte(struct ds_device *dev, u8 byte)
608{
609	int err;
610	struct ds_status st;
611	u8 rbyte;
612
613	err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, byte);
614	if (err)
615		return err;
616
617	if (dev->spu_bit)
618		msleep(dev->spu_sleep);
619
620	err = ds_wait_status(dev, &st);
621	if (err)
622		return err;
623
624	err = ds_recv_data(dev, &rbyte, sizeof(rbyte));
625	if (err < 0)
626		return err;
627
628	return !(byte == rbyte);
629}
630
631static int ds_read_byte(struct ds_device *dev, u8 *byte)
632{
633	int err;
634	struct ds_status st;
635
636	err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM , 0xff);
637	if (err)
638		return err;
639
640	ds_wait_status(dev, &st);
641
642	err = ds_recv_data(dev, byte, sizeof(*byte));
643	if (err < 0)
644		return err;
645
646	return 0;
647}
648
649static int ds_read_block(struct ds_device *dev, u8 *buf, int len)
650{
651	struct ds_status st;
652	int err;
653
654	if (len > 64*1024)
655		return -E2BIG;
656
657	memset(buf, 0xFF, len);
658
659	err = ds_send_data(dev, buf, len);
660	if (err < 0)
661		return err;
662
663	err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM, len);
664	if (err)
665		return err;
666
667	ds_wait_status(dev, &st);
668
669	memset(buf, 0x00, len);
670	err = ds_recv_data(dev, buf, len);
671
672	return err;
673}
674
675static int ds_write_block(struct ds_device *dev, u8 *buf, int len)
676{
677	int err;
678	struct ds_status st;
679
680	err = ds_send_data(dev, buf, len);
681	if (err < 0)
682		return err;
683
684	err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, len);
685	if (err)
686		return err;
687
688	if (dev->spu_bit)
689		msleep(dev->spu_sleep);
690
691	ds_wait_status(dev, &st);
692
693	err = ds_recv_data(dev, buf, len);
694	if (err < 0)
695		return err;
696
697	return !(err == len);
698}
699
700static void ds9490r_search(void *data, struct w1_master *master,
701	u8 search_type, w1_slave_found_callback callback)
702{
703	/* When starting with an existing id, the first id returned will
704	 * be that device (if it is still on the bus most likely).
705	 *
706	 * If the number of devices found is less than or equal to the
707	 * search_limit, that number of IDs will be returned.  If there are
708	 * more, search_limit IDs will be returned followed by a non-zero
709	 * discrepency value.
710	 */
711	struct ds_device *dev = data;
712	int err;
713	u16 value, index;
714	struct ds_status st;
715	u8 st_buf[ST_SIZE];
716	int search_limit;
717	int found = 0;
718	int i;
719
720	/* DS18b20 spec, 13.16 ms per device, 75 per second, sleep for
721	 * discovering 8 devices (1 bulk transfer and 1/2 FIFO size) at a time.
722	 */
723	const unsigned long jtime = msecs_to_jiffies(1000*8/75);
724	/* FIFO 128 bytes, bulk packet size 64, read a multiple of the
725	 * packet size.
726	 */
727	u64 buf[2*64/8];
728
729	mutex_lock(&master->bus_mutex);
730
731	/* address to start searching at */
732	if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0)
733		goto search_out;
734	master->search_id = 0;
735
736	value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F |
737		COMM_RTS;
738	search_limit = master->max_slave_count;
739	if (search_limit > 255)
740		search_limit = 0;
741	index = search_type | (search_limit << 8);
742	if (ds_send_control(dev, value, index) < 0)
743		goto search_out;
744
745	do {
746		schedule_timeout(jtime);
747
748		if (ds_recv_status_nodump(dev, &st, st_buf, sizeof(st_buf)) <
749			sizeof(st)) {
750			break;
751		}
752
753		if (st.data_in_buffer_status) {
754			/* Bulk in can receive partial ids, but when it does
755			 * they fail crc and will be discarded anyway.
756			 * That has only been seen when status in buffer
757			 * is 0 and bulk is read anyway, so don't read
758			 * bulk without first checking if status says there
759			 * is data to read.
760			 */
761			err = ds_recv_data(dev, (u8 *)buf, sizeof(buf));
762			if (err < 0)
763				break;
764			for (i = 0; i < err/8; ++i) {
765				++found;
766				if (found <= search_limit)
767					callback(master, buf[i]);
768				/* can't know if there will be a discrepancy
769				 * value after until the next id */
770				if (found == search_limit)
771					master->search_id = buf[i];
772			}
773		}
774
775		if (test_bit(W1_ABORT_SEARCH, &master->flags))
776			break;
777	} while (!(st.status & (ST_IDLE | ST_HALT)));
778
779	/* only continue the search if some weren't found */
780	if (found <= search_limit) {
781		master->search_id = 0;
782	} else if (!test_bit(W1_WARN_MAX_COUNT, &master->flags)) {
783		/* Only max_slave_count will be scanned in a search,
784		 * but it will start where it left off next search
785		 * until all ids are identified and then it will start
786		 * over.  A continued search will report the previous
787		 * last id as the first id (provided it is still on the
788		 * bus).
789		 */
790		dev_info(&dev->udev->dev, "%s: max_slave_count %d reached, "
791			"will continue next search.\n", __func__,
792			master->max_slave_count);
793		set_bit(W1_WARN_MAX_COUNT, &master->flags);
794	}
795search_out:
796	mutex_unlock(&master->bus_mutex);
797}
798
799#if 0
800static int ds_match_access(struct ds_device *dev, u64 init)
801{
802	int err;
803	struct ds_status st;
804
805	err = ds_send_data(dev, (unsigned char *)&init, sizeof(init));
806	if (err)
807		return err;
808
809	ds_wait_status(dev, &st);
810
811	err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055);
812	if (err)
813		return err;
814
815	ds_wait_status(dev, &st);
816
817	return 0;
818}
819
820static int ds_set_path(struct ds_device *dev, u64 init)
821{
822	int err;
823	struct ds_status st;
824	u8 buf[9];
825
826	memcpy(buf, &init, 8);
827	buf[8] = BRANCH_MAIN;
828
829	err = ds_send_data(dev, buf, sizeof(buf));
830	if (err)
831		return err;
832
833	ds_wait_status(dev, &st);
834
835	err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0);
836	if (err)
837		return err;
838
839	ds_wait_status(dev, &st);
840
841	return 0;
842}
843
844#endif  /*  0  */
845
846static u8 ds9490r_touch_bit(void *data, u8 bit)
847{
848	u8 ret;
849	struct ds_device *dev = data;
850
851	if (ds_touch_bit(dev, bit, &ret))
852		return 0;
853
854	return ret;
855}
856
857#if 0
858static void ds9490r_write_bit(void *data, u8 bit)
859{
860	struct ds_device *dev = data;
861
862	ds_write_bit(dev, bit);
863}
864
865static u8 ds9490r_read_bit(void *data)
866{
867	struct ds_device *dev = data;
868	int err;
869	u8 bit = 0;
870
871	err = ds_touch_bit(dev, 1, &bit);
872	if (err)
873		return 0;
874
875	return bit & 1;
876}
877#endif
878
879static void ds9490r_write_byte(void *data, u8 byte)
880{
881	struct ds_device *dev = data;
882
883	ds_write_byte(dev, byte);
884}
885
886static u8 ds9490r_read_byte(void *data)
887{
888	struct ds_device *dev = data;
889	int err;
890	u8 byte = 0;
891
892	err = ds_read_byte(dev, &byte);
893	if (err)
894		return 0;
895
896	return byte;
897}
898
899static void ds9490r_write_block(void *data, const u8 *buf, int len)
900{
901	struct ds_device *dev = data;
902
903	ds_write_block(dev, (u8 *)buf, len);
904}
905
906static u8 ds9490r_read_block(void *data, u8 *buf, int len)
907{
908	struct ds_device *dev = data;
909	int err;
910
911	err = ds_read_block(dev, buf, len);
912	if (err < 0)
913		return 0;
914
915	return len;
916}
917
918static u8 ds9490r_reset(void *data)
919{
920	struct ds_device *dev = data;
921	int err;
922
923	err = ds_reset(dev);
924	if (err)
925		return 1;
926
927	return 0;
928}
929
930static u8 ds9490r_set_pullup(void *data, int delay)
931{
932	struct ds_device *dev = data;
933
934	if (ds_set_pullup(dev, delay))
935		return 1;
936
937	return 0;
938}
939
940static int ds_w1_init(struct ds_device *dev)
941{
942	memset(&dev->master, 0, sizeof(struct w1_bus_master));
943
944	/* Reset the device as it can be in a bad state.
945	 * This is necessary because a block write will wait for data
946	 * to be placed in the output buffer and block any later
947	 * commands which will keep accumulating and the device will
948	 * not be idle.  Another case is removing the ds2490 module
949	 * while a bus search is in progress, somehow a few commands
950	 * get through, but the input transfers fail leaving data in
951	 * the input buffer.  This will cause the next read to fail
952	 * see the note in ds_recv_data.
953	 */
954	ds_reset_device(dev);
955
956	dev->master.data	= dev;
957	dev->master.touch_bit	= &ds9490r_touch_bit;
958	/* read_bit and write_bit in w1_bus_master are expected to set and
959	 * sample the line level.  For write_bit that means it is expected to
960	 * set it to that value and leave it there.  ds2490 only supports an
961	 * individual time slot at the lowest level.  The requirement from
962	 * pulling the bus state down to reading the state is 15us, something
963	 * that isn't realistic on the USB bus anyway.
964	dev->master.read_bit	= &ds9490r_read_bit;
965	dev->master.write_bit	= &ds9490r_write_bit;
966	*/
967	dev->master.read_byte	= &ds9490r_read_byte;
968	dev->master.write_byte	= &ds9490r_write_byte;
969	dev->master.read_block	= &ds9490r_read_block;
970	dev->master.write_block	= &ds9490r_write_block;
971	dev->master.reset_bus	= &ds9490r_reset;
972	dev->master.set_pullup	= &ds9490r_set_pullup;
973	dev->master.search	= &ds9490r_search;
974
975	return w1_add_master_device(&dev->master);
976}
977
978static void ds_w1_fini(struct ds_device *dev)
979{
980	w1_remove_master_device(&dev->master);
981}
982
983static int ds_probe(struct usb_interface *intf,
984		    const struct usb_device_id *udev_id)
985{
986	struct usb_device *udev = interface_to_usbdev(intf);
987	struct usb_endpoint_descriptor *endpoint;
988	struct usb_host_interface *iface_desc;
989	struct ds_device *dev;
990	int i, err, alt;
991
992	dev = kzalloc(sizeof(struct ds_device), GFP_KERNEL);
993	if (!dev) {
994		pr_info("Failed to allocate new DS9490R structure.\n");
995		return -ENOMEM;
996	}
997	dev->udev = usb_get_dev(udev);
998	if (!dev->udev) {
999		err = -ENOMEM;
1000		goto err_out_free;
1001	}
1002	memset(dev->ep, 0, sizeof(dev->ep));
1003
1004	usb_set_intfdata(intf, dev);
1005
1006	err = usb_reset_configuration(dev->udev);
1007	if (err) {
1008		dev_err(&dev->udev->dev,
1009			"Failed to reset configuration: err=%d.\n", err);
1010		goto err_out_clear;
1011	}
1012
1013	/* alternative 3, 1ms interrupt (greatly speeds search), 64 byte bulk */
1014	alt = 3;
1015	err = usb_set_interface(dev->udev,
1016		intf->altsetting[alt].desc.bInterfaceNumber, alt);
1017	if (err) {
1018		dev_err(&dev->udev->dev, "Failed to set alternative setting %d "
1019			"for %d interface: err=%d.\n", alt,
1020			intf->altsetting[alt].desc.bInterfaceNumber, err);
1021		goto err_out_clear;
1022	}
1023
1024	iface_desc = &intf->altsetting[alt];
1025	if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
1026		pr_info("Num endpoints=%d. It is not DS9490R.\n",
1027			iface_desc->desc.bNumEndpoints);
1028		err = -EINVAL;
1029		goto err_out_clear;
1030	}
1031
1032	/*
1033	 * This loop doesn'd show control 0 endpoint,
1034	 * so we will fill only 1-3 endpoints entry.
1035	 */
1036	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
1037		endpoint = &iface_desc->endpoint[i].desc;
1038
1039		dev->ep[i+1] = endpoint->bEndpointAddress;
1040#if 0
1041		printk("%d: addr=%x, size=%d, dir=%s, type=%x\n",
1042			i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize),
1043			(endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT",
1044			endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK);
1045#endif
1046	}
1047
1048	err = ds_w1_init(dev);
1049	if (err)
1050		goto err_out_clear;
1051
1052	mutex_lock(&ds_mutex);
1053	list_add_tail(&dev->ds_entry, &ds_devices);
1054	mutex_unlock(&ds_mutex);
1055
1056	return 0;
1057
1058err_out_clear:
1059	usb_set_intfdata(intf, NULL);
1060	usb_put_dev(dev->udev);
1061err_out_free:
1062	kfree(dev);
1063	return err;
1064}
1065
1066static void ds_disconnect(struct usb_interface *intf)
1067{
1068	struct ds_device *dev;
1069
1070	dev = usb_get_intfdata(intf);
1071	if (!dev)
1072		return;
1073
1074	mutex_lock(&ds_mutex);
1075	list_del(&dev->ds_entry);
1076	mutex_unlock(&ds_mutex);
1077
1078	ds_w1_fini(dev);
1079
1080	usb_set_intfdata(intf, NULL);
1081
1082	usb_put_dev(dev->udev);
1083	kfree(dev);
1084}
1085
1086module_usb_driver(ds_driver);
1087
1088MODULE_LICENSE("GPL");
1089MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
1090MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)");
1091