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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Atmel AT45xxx DataFlash MTD driver for lightweight SPI framework
4 *
5 * Largely derived from at91_dataflash.c:
6 * Copyright (C) 2003-2005 SAN People (Pty) Ltd
7*/
8#include <linux/module.h>
9#include <linux/slab.h>
10#include <linux/delay.h>
11#include <linux/device.h>
12#include <linux/mutex.h>
13#include <linux/err.h>
14#include <linux/math64.h>
15#include <linux/of.h>
16#include <linux/of_device.h>
17
18#include <linux/spi/spi.h>
19#include <linux/spi/flash.h>
20
21#include <linux/mtd/mtd.h>
22#include <linux/mtd/partitions.h>
23
24/*
25 * DataFlash is a kind of SPI flash. Most AT45 chips have two buffers in
26 * each chip, which may be used for double buffered I/O; but this driver
27 * doesn't (yet) use these for any kind of i/o overlap or prefetching.
28 *
29 * Sometimes DataFlash is packaged in MMC-format cards, although the
30 * MMC stack can't (yet?) distinguish between MMC and DataFlash
31 * protocols during enumeration.
32 */
33
34/* reads can bypass the buffers */
35#define OP_READ_CONTINUOUS 0xE8
36#define OP_READ_PAGE 0xD2
37
38/* group B requests can run even while status reports "busy" */
39#define OP_READ_STATUS 0xD7 /* group B */
40
41/* move data between host and buffer */
42#define OP_READ_BUFFER1 0xD4 /* group B */
43#define OP_READ_BUFFER2 0xD6 /* group B */
44#define OP_WRITE_BUFFER1 0x84 /* group B */
45#define OP_WRITE_BUFFER2 0x87 /* group B */
46
47/* erasing flash */
48#define OP_ERASE_PAGE 0x81
49#define OP_ERASE_BLOCK 0x50
50
51/* move data between buffer and flash */
52#define OP_TRANSFER_BUF1 0x53
53#define OP_TRANSFER_BUF2 0x55
54#define OP_MREAD_BUFFER1 0xD4
55#define OP_MREAD_BUFFER2 0xD6
56#define OP_MWERASE_BUFFER1 0x83
57#define OP_MWERASE_BUFFER2 0x86
58#define OP_MWRITE_BUFFER1 0x88 /* sector must be pre-erased */
59#define OP_MWRITE_BUFFER2 0x89 /* sector must be pre-erased */
60
61/* write to buffer, then write-erase to flash */
62#define OP_PROGRAM_VIA_BUF1 0x82
63#define OP_PROGRAM_VIA_BUF2 0x85
64
65/* compare buffer to flash */
66#define OP_COMPARE_BUF1 0x60
67#define OP_COMPARE_BUF2 0x61
68
69/* read flash to buffer, then write-erase to flash */
70#define OP_REWRITE_VIA_BUF1 0x58
71#define OP_REWRITE_VIA_BUF2 0x59
72
73/* newer chips report JEDEC manufacturer and device IDs; chip
74 * serial number and OTP bits; and per-sector writeprotect.
75 */
76#define OP_READ_ID 0x9F
77#define OP_READ_SECURITY 0x77
78#define OP_WRITE_SECURITY_REVC 0x9A
79#define OP_WRITE_SECURITY 0x9B /* revision D */
80
81#define CFI_MFR_ATMEL 0x1F
82
83#define DATAFLASH_SHIFT_EXTID 24
84#define DATAFLASH_SHIFT_ID 40
85
86struct dataflash {
87 u8 command[4];
88 char name[24];
89
90 unsigned short page_offset; /* offset in flash address */
91 unsigned int page_size; /* of bytes per page */
92
93 struct mutex lock;
94 struct spi_device *spi;
95
96 struct mtd_info mtd;
97};
98
99#ifdef CONFIG_OF
100static const struct of_device_id dataflash_dt_ids[] = {
101 { .compatible = "atmel,at45", },
102 { .compatible = "atmel,dataflash", },
103 { /* sentinel */ }
104};
105MODULE_DEVICE_TABLE(of, dataflash_dt_ids);
106#endif
107
108/* ......................................................................... */
109
110/*
111 * Return the status of the DataFlash device.
112 */
113static inline int dataflash_status(struct spi_device *spi)
114{
115 /* NOTE: at45db321c over 25 MHz wants to write
116 * a dummy byte after the opcode...
117 */
118 return spi_w8r8(spi, OP_READ_STATUS);
119}
120
121/*
122 * Poll the DataFlash device until it is READY.
123 * This usually takes 5-20 msec or so; more for sector erase.
124 */
125static int dataflash_waitready(struct spi_device *spi)
126{
127 int status;
128
129 for (;;) {
130 status = dataflash_status(spi);
131 if (status < 0) {
132 dev_dbg(&spi->dev, "status %d?\n", status);
133 status = 0;
134 }
135
136 if (status & (1 << 7)) /* RDY/nBSY */
137 return status;
138
139 usleep_range(3000, 4000);
140 }
141}
142
143/* ......................................................................... */
144
145/*
146 * Erase pages of flash.
147 */
148static int dataflash_erase(struct mtd_info *mtd, struct erase_info *instr)
149{
150 struct dataflash *priv = mtd->priv;
151 struct spi_device *spi = priv->spi;
152 struct spi_transfer x = { };
153 struct spi_message msg;
154 unsigned blocksize = priv->page_size << 3;
155 u8 *command;
156 u32 rem;
157
158 dev_dbg(&spi->dev, "erase addr=0x%llx len 0x%llx\n",
159 (long long)instr->addr, (long long)instr->len);
160
161 div_u64_rem(instr->len, priv->page_size, &rem);
162 if (rem)
163 return -EINVAL;
164 div_u64_rem(instr->addr, priv->page_size, &rem);
165 if (rem)
166 return -EINVAL;
167
168 spi_message_init(&msg);
169
170 x.tx_buf = command = priv->command;
171 x.len = 4;
172 spi_message_add_tail(&x, &msg);
173
174 mutex_lock(&priv->lock);
175 while (instr->len > 0) {
176 unsigned int pageaddr;
177 int status;
178 int do_block;
179
180 /* Calculate flash page address; use block erase (for speed) if
181 * we're at a block boundary and need to erase the whole block.
182 */
183 pageaddr = div_u64(instr->addr, priv->page_size);
184 do_block = (pageaddr & 0x7) == 0 && instr->len >= blocksize;
185 pageaddr = pageaddr << priv->page_offset;
186
187 command[0] = do_block ? OP_ERASE_BLOCK : OP_ERASE_PAGE;
188 command[1] = (u8)(pageaddr >> 16);
189 command[2] = (u8)(pageaddr >> 8);
190 command[3] = 0;
191
192 dev_dbg(&spi->dev, "ERASE %s: (%x) %x %x %x [%i]\n",
193 do_block ? "block" : "page",
194 command[0], command[1], command[2], command[3],
195 pageaddr);
196
197 status = spi_sync(spi, &msg);
198 (void) dataflash_waitready(spi);
199
200 if (status < 0) {
201 dev_err(&spi->dev, "erase %x, err %d\n",
202 pageaddr, status);
203 /* REVISIT: can retry instr->retries times; or
204 * giveup and instr->fail_addr = instr->addr;
205 */
206 continue;
207 }
208
209 if (do_block) {
210 instr->addr += blocksize;
211 instr->len -= blocksize;
212 } else {
213 instr->addr += priv->page_size;
214 instr->len -= priv->page_size;
215 }
216 }
217 mutex_unlock(&priv->lock);
218
219 return 0;
220}
221
222/*
223 * Read from the DataFlash device.
224 * from : Start offset in flash device
225 * len : Amount to read
226 * retlen : About of data actually read
227 * buf : Buffer containing the data
228 */
229static int dataflash_read(struct mtd_info *mtd, loff_t from, size_t len,
230 size_t *retlen, u_char *buf)
231{
232 struct dataflash *priv = mtd->priv;
233 struct spi_transfer x[2] = { };
234 struct spi_message msg;
235 unsigned int addr;
236 u8 *command;
237 int status;
238
239 dev_dbg(&priv->spi->dev, "read 0x%x..0x%x\n",
240 (unsigned int)from, (unsigned int)(from + len));
241
242 /* Calculate flash page/byte address */
243 addr = (((unsigned)from / priv->page_size) << priv->page_offset)
244 + ((unsigned)from % priv->page_size);
245
246 command = priv->command;
247
248 dev_dbg(&priv->spi->dev, "READ: (%x) %x %x %x\n",
249 command[0], command[1], command[2], command[3]);
250
251 spi_message_init(&msg);
252
253 x[0].tx_buf = command;
254 x[0].len = 8;
255 spi_message_add_tail(&x[0], &msg);
256
257 x[1].rx_buf = buf;
258 x[1].len = len;
259 spi_message_add_tail(&x[1], &msg);
260
261 mutex_lock(&priv->lock);
262
263 /* Continuous read, max clock = f(car) which may be less than
264 * the peak rate available. Some chips support commands with
265 * fewer "don't care" bytes. Both buffers stay unchanged.
266 */
267 command[0] = OP_READ_CONTINUOUS;
268 command[1] = (u8)(addr >> 16);
269 command[2] = (u8)(addr >> 8);
270 command[3] = (u8)(addr >> 0);
271 /* plus 4 "don't care" bytes */
272
273 status = spi_sync(priv->spi, &msg);
274 mutex_unlock(&priv->lock);
275
276 if (status >= 0) {
277 *retlen = msg.actual_length - 8;
278 status = 0;
279 } else
280 dev_dbg(&priv->spi->dev, "read %x..%x --> %d\n",
281 (unsigned)from, (unsigned)(from + len),
282 status);
283 return status;
284}
285
286/*
287 * Write to the DataFlash device.
288 * to : Start offset in flash device
289 * len : Amount to write
290 * retlen : Amount of data actually written
291 * buf : Buffer containing the data
292 */
293static int dataflash_write(struct mtd_info *mtd, loff_t to, size_t len,
294 size_t * retlen, const u_char * buf)
295{
296 struct dataflash *priv = mtd->priv;
297 struct spi_device *spi = priv->spi;
298 struct spi_transfer x[2] = { };
299 struct spi_message msg;
300 unsigned int pageaddr, addr, offset, writelen;
301 size_t remaining = len;
302 u_char *writebuf = (u_char *) buf;
303 int status = -EINVAL;
304 u8 *command;
305
306 dev_dbg(&spi->dev, "write 0x%x..0x%x\n",
307 (unsigned int)to, (unsigned int)(to + len));
308
309 spi_message_init(&msg);
310
311 x[0].tx_buf = command = priv->command;
312 x[0].len = 4;
313 spi_message_add_tail(&x[0], &msg);
314
315 pageaddr = ((unsigned)to / priv->page_size);
316 offset = ((unsigned)to % priv->page_size);
317 if (offset + len > priv->page_size)
318 writelen = priv->page_size - offset;
319 else
320 writelen = len;
321
322 mutex_lock(&priv->lock);
323 while (remaining > 0) {
324 dev_dbg(&spi->dev, "write @ %i:%i len=%i\n",
325 pageaddr, offset, writelen);
326
327 /* REVISIT:
328 * (a) each page in a sector must be rewritten at least
329 * once every 10K sibling erase/program operations.
330 * (b) for pages that are already erased, we could
331 * use WRITE+MWRITE not PROGRAM for ~30% speedup.
332 * (c) WRITE to buffer could be done while waiting for
333 * a previous MWRITE/MWERASE to complete ...
334 * (d) error handling here seems to be mostly missing.
335 *
336 * Two persistent bits per page, plus a per-sector counter,
337 * could support (a) and (b) ... we might consider using
338 * the second half of sector zero, which is just one block,
339 * to track that state. (On AT91, that sector should also
340 * support boot-from-DataFlash.)
341 */
342
343 addr = pageaddr << priv->page_offset;
344
345 /* (1) Maybe transfer partial page to Buffer1 */
346 if (writelen != priv->page_size) {
347 command[0] = OP_TRANSFER_BUF1;
348 command[1] = (addr & 0x00FF0000) >> 16;
349 command[2] = (addr & 0x0000FF00) >> 8;
350 command[3] = 0;
351
352 dev_dbg(&spi->dev, "TRANSFER: (%x) %x %x %x\n",
353 command[0], command[1], command[2], command[3]);
354
355 status = spi_sync(spi, &msg);
356 if (status < 0)
357 dev_dbg(&spi->dev, "xfer %u -> %d\n",
358 addr, status);
359
360 (void) dataflash_waitready(priv->spi);
361 }
362
363 /* (2) Program full page via Buffer1 */
364 addr += offset;
365 command[0] = OP_PROGRAM_VIA_BUF1;
366 command[1] = (addr & 0x00FF0000) >> 16;
367 command[2] = (addr & 0x0000FF00) >> 8;
368 command[3] = (addr & 0x000000FF);
369
370 dev_dbg(&spi->dev, "PROGRAM: (%x) %x %x %x\n",
371 command[0], command[1], command[2], command[3]);
372
373 x[1].tx_buf = writebuf;
374 x[1].len = writelen;
375 spi_message_add_tail(x + 1, &msg);
376 status = spi_sync(spi, &msg);
377 spi_transfer_del(x + 1);
378 if (status < 0)
379 dev_dbg(&spi->dev, "pgm %u/%u -> %d\n",
380 addr, writelen, status);
381
382 (void) dataflash_waitready(priv->spi);
383
384
385#ifdef CONFIG_MTD_DATAFLASH_WRITE_VERIFY
386
387 /* (3) Compare to Buffer1 */
388 addr = pageaddr << priv->page_offset;
389 command[0] = OP_COMPARE_BUF1;
390 command[1] = (addr & 0x00FF0000) >> 16;
391 command[2] = (addr & 0x0000FF00) >> 8;
392 command[3] = 0;
393
394 dev_dbg(&spi->dev, "COMPARE: (%x) %x %x %x\n",
395 command[0], command[1], command[2], command[3]);
396
397 status = spi_sync(spi, &msg);
398 if (status < 0)
399 dev_dbg(&spi->dev, "compare %u -> %d\n",
400 addr, status);
401
402 status = dataflash_waitready(priv->spi);
403
404 /* Check result of the compare operation */
405 if (status & (1 << 6)) {
406 dev_err(&spi->dev, "compare page %u, err %d\n",
407 pageaddr, status);
408 remaining = 0;
409 status = -EIO;
410 break;
411 } else
412 status = 0;
413
414#endif /* CONFIG_MTD_DATAFLASH_WRITE_VERIFY */
415
416 remaining = remaining - writelen;
417 pageaddr++;
418 offset = 0;
419 writebuf += writelen;
420 *retlen += writelen;
421
422 if (remaining > priv->page_size)
423 writelen = priv->page_size;
424 else
425 writelen = remaining;
426 }
427 mutex_unlock(&priv->lock);
428
429 return status;
430}
431
432/* ......................................................................... */
433
434#ifdef CONFIG_MTD_DATAFLASH_OTP
435
436static int dataflash_get_otp_info(struct mtd_info *mtd, size_t len,
437 size_t *retlen, struct otp_info *info)
438{
439 /* Report both blocks as identical: bytes 0..64, locked.
440 * Unless the user block changed from all-ones, we can't
441 * tell whether it's still writable; so we assume it isn't.
442 */
443 info->start = 0;
444 info->length = 64;
445 info->locked = 1;
446 *retlen = sizeof(*info);
447 return 0;
448}
449
450static ssize_t otp_read(struct spi_device *spi, unsigned base,
451 u8 *buf, loff_t off, size_t len)
452{
453 struct spi_message m;
454 size_t l;
455 u8 *scratch;
456 struct spi_transfer t;
457 int status;
458
459 if (off > 64)
460 return -EINVAL;
461
462 if ((off + len) > 64)
463 len = 64 - off;
464
465 spi_message_init(&m);
466
467 l = 4 + base + off + len;
468 scratch = kzalloc(l, GFP_KERNEL);
469 if (!scratch)
470 return -ENOMEM;
471
472 /* OUT: OP_READ_SECURITY, 3 don't-care bytes, zeroes
473 * IN: ignore 4 bytes, data bytes 0..N (max 127)
474 */
475 scratch[0] = OP_READ_SECURITY;
476
477 memset(&t, 0, sizeof t);
478 t.tx_buf = scratch;
479 t.rx_buf = scratch;
480 t.len = l;
481 spi_message_add_tail(&t, &m);
482
483 dataflash_waitready(spi);
484
485 status = spi_sync(spi, &m);
486 if (status >= 0) {
487 memcpy(buf, scratch + 4 + base + off, len);
488 status = len;
489 }
490
491 kfree(scratch);
492 return status;
493}
494
495static int dataflash_read_fact_otp(struct mtd_info *mtd,
496 loff_t from, size_t len, size_t *retlen, u_char *buf)
497{
498 struct dataflash *priv = mtd->priv;
499 int status;
500
501 /* 64 bytes, from 0..63 ... start at 64 on-chip */
502 mutex_lock(&priv->lock);
503 status = otp_read(priv->spi, 64, buf, from, len);
504 mutex_unlock(&priv->lock);
505
506 if (status < 0)
507 return status;
508 *retlen = status;
509 return 0;
510}
511
512static int dataflash_read_user_otp(struct mtd_info *mtd,
513 loff_t from, size_t len, size_t *retlen, u_char *buf)
514{
515 struct dataflash *priv = mtd->priv;
516 int status;
517
518 /* 64 bytes, from 0..63 ... start at 0 on-chip */
519 mutex_lock(&priv->lock);
520 status = otp_read(priv->spi, 0, buf, from, len);
521 mutex_unlock(&priv->lock);
522
523 if (status < 0)
524 return status;
525 *retlen = status;
526 return 0;
527}
528
529static int dataflash_write_user_otp(struct mtd_info *mtd,
530 loff_t from, size_t len, size_t *retlen, u_char *buf)
531{
532 struct spi_message m;
533 const size_t l = 4 + 64;
534 u8 *scratch;
535 struct spi_transfer t;
536 struct dataflash *priv = mtd->priv;
537 int status;
538
539 if (from >= 64) {
540 /*
541 * Attempting to write beyond the end of OTP memory,
542 * no data can be written.
543 */
544 *retlen = 0;
545 return 0;
546 }
547
548 /* Truncate the write to fit into OTP memory. */
549 if ((from + len) > 64)
550 len = 64 - from;
551
552 /* OUT: OP_WRITE_SECURITY, 3 zeroes, 64 data-or-zero bytes
553 * IN: ignore all
554 */
555 scratch = kzalloc(l, GFP_KERNEL);
556 if (!scratch)
557 return -ENOMEM;
558 scratch[0] = OP_WRITE_SECURITY;
559 memcpy(scratch + 4 + from, buf, len);
560
561 spi_message_init(&m);
562
563 memset(&t, 0, sizeof t);
564 t.tx_buf = scratch;
565 t.len = l;
566 spi_message_add_tail(&t, &m);
567
568 /* Write the OTP bits, if they've not yet been written.
569 * This modifies SRAM buffer1.
570 */
571 mutex_lock(&priv->lock);
572 dataflash_waitready(priv->spi);
573 status = spi_sync(priv->spi, &m);
574 mutex_unlock(&priv->lock);
575
576 kfree(scratch);
577
578 if (status >= 0) {
579 status = 0;
580 *retlen = len;
581 }
582 return status;
583}
584
585static char *otp_setup(struct mtd_info *device, char revision)
586{
587 device->_get_fact_prot_info = dataflash_get_otp_info;
588 device->_read_fact_prot_reg = dataflash_read_fact_otp;
589 device->_get_user_prot_info = dataflash_get_otp_info;
590 device->_read_user_prot_reg = dataflash_read_user_otp;
591
592 /* rev c parts (at45db321c and at45db1281 only!) use a
593 * different write procedure; not (yet?) implemented.
594 */
595 if (revision > 'c')
596 device->_write_user_prot_reg = dataflash_write_user_otp;
597
598 return ", OTP";
599}
600
601#else
602
603static char *otp_setup(struct mtd_info *device, char revision)
604{
605 return " (OTP)";
606}
607
608#endif
609
610/* ......................................................................... */
611
612/*
613 * Register DataFlash device with MTD subsystem.
614 */
615static int add_dataflash_otp(struct spi_device *spi, char *name, int nr_pages,
616 int pagesize, int pageoffset, char revision)
617{
618 struct dataflash *priv;
619 struct mtd_info *device;
620 struct flash_platform_data *pdata = dev_get_platdata(&spi->dev);
621 char *otp_tag = "";
622 int err = 0;
623
624 priv = kzalloc(sizeof *priv, GFP_KERNEL);
625 if (!priv)
626 return -ENOMEM;
627
628 mutex_init(&priv->lock);
629 priv->spi = spi;
630 priv->page_size = pagesize;
631 priv->page_offset = pageoffset;
632
633 /* name must be usable with cmdlinepart */
634 sprintf(priv->name, "spi%d.%d-%s",
635 spi->master->bus_num, spi->chip_select,
636 name);
637
638 device = &priv->mtd;
639 device->name = (pdata && pdata->name) ? pdata->name : priv->name;
640 device->size = nr_pages * pagesize;
641 device->erasesize = pagesize;
642 device->writesize = pagesize;
643 device->type = MTD_DATAFLASH;
644 device->flags = MTD_WRITEABLE;
645 device->_erase = dataflash_erase;
646 device->_read = dataflash_read;
647 device->_write = dataflash_write;
648 device->priv = priv;
649
650 device->dev.parent = &spi->dev;
651 mtd_set_of_node(device, spi->dev.of_node);
652
653 if (revision >= 'c')
654 otp_tag = otp_setup(device, revision);
655
656 dev_info(&spi->dev, "%s (%lld KBytes) pagesize %d bytes%s\n",
657 name, (long long)((device->size + 1023) >> 10),
658 pagesize, otp_tag);
659 spi_set_drvdata(spi, priv);
660
661 err = mtd_device_register(device,
662 pdata ? pdata->parts : NULL,
663 pdata ? pdata->nr_parts : 0);
664
665 if (!err)
666 return 0;
667
668 kfree(priv);
669 return err;
670}
671
672static inline int add_dataflash(struct spi_device *spi, char *name,
673 int nr_pages, int pagesize, int pageoffset)
674{
675 return add_dataflash_otp(spi, name, nr_pages, pagesize,
676 pageoffset, 0);
677}
678
679struct flash_info {
680 char *name;
681
682 /* JEDEC id has a high byte of zero plus three data bytes:
683 * the manufacturer id, then a two byte device id.
684 */
685 u64 jedec_id;
686
687 /* The size listed here is what works with OP_ERASE_PAGE. */
688 unsigned nr_pages;
689 u16 pagesize;
690 u16 pageoffset;
691
692 u16 flags;
693#define SUP_EXTID 0x0004 /* supports extended ID data */
694#define SUP_POW2PS 0x0002 /* supports 2^N byte pages */
695#define IS_POW2PS 0x0001 /* uses 2^N byte pages */
696};
697
698static struct flash_info dataflash_data[] = {
699
700 /*
701 * NOTE: chips with SUP_POW2PS (rev D and up) need two entries,
702 * one with IS_POW2PS and the other without. The entry with the
703 * non-2^N byte page size can't name exact chip revisions without
704 * losing backwards compatibility for cmdlinepart.
705 *
706 * These newer chips also support 128-byte security registers (with
707 * 64 bytes one-time-programmable) and software write-protection.
708 */
709 { "AT45DB011B", 0x1f2200, 512, 264, 9, SUP_POW2PS},
710 { "at45db011d", 0x1f2200, 512, 256, 8, SUP_POW2PS | IS_POW2PS},
711
712 { "AT45DB021B", 0x1f2300, 1024, 264, 9, SUP_POW2PS},
713 { "at45db021d", 0x1f2300, 1024, 256, 8, SUP_POW2PS | IS_POW2PS},
714
715 { "AT45DB041x", 0x1f2400, 2048, 264, 9, SUP_POW2PS},
716 { "at45db041d", 0x1f2400, 2048, 256, 8, SUP_POW2PS | IS_POW2PS},
717
718 { "AT45DB081B", 0x1f2500, 4096, 264, 9, SUP_POW2PS},
719 { "at45db081d", 0x1f2500, 4096, 256, 8, SUP_POW2PS | IS_POW2PS},
720
721 { "AT45DB161x", 0x1f2600, 4096, 528, 10, SUP_POW2PS},
722 { "at45db161d", 0x1f2600, 4096, 512, 9, SUP_POW2PS | IS_POW2PS},
723
724 { "AT45DB321x", 0x1f2700, 8192, 528, 10, 0}, /* rev C */
725
726 { "AT45DB321x", 0x1f2701, 8192, 528, 10, SUP_POW2PS},
727 { "at45db321d", 0x1f2701, 8192, 512, 9, SUP_POW2PS | IS_POW2PS},
728
729 { "AT45DB642x", 0x1f2800, 8192, 1056, 11, SUP_POW2PS},
730 { "at45db642d", 0x1f2800, 8192, 1024, 10, SUP_POW2PS | IS_POW2PS},
731
732 { "AT45DB641E", 0x1f28000100ULL, 32768, 264, 9, SUP_EXTID | SUP_POW2PS},
733 { "at45db641e", 0x1f28000100ULL, 32768, 256, 8, SUP_EXTID | SUP_POW2PS | IS_POW2PS},
734};
735
736static struct flash_info *jedec_lookup(struct spi_device *spi,
737 u64 jedec, bool use_extid)
738{
739 struct flash_info *info;
740 int status;
741
742 for (info = dataflash_data;
743 info < dataflash_data + ARRAY_SIZE(dataflash_data);
744 info++) {
745 if (use_extid && !(info->flags & SUP_EXTID))
746 continue;
747
748 if (info->jedec_id == jedec) {
749 dev_dbg(&spi->dev, "OTP, sector protect%s\n",
750 (info->flags & SUP_POW2PS) ?
751 ", binary pagesize" : "");
752 if (info->flags & SUP_POW2PS) {
753 status = dataflash_status(spi);
754 if (status < 0) {
755 dev_dbg(&spi->dev, "status error %d\n",
756 status);
757 return ERR_PTR(status);
758 }
759 if (status & 0x1) {
760 if (info->flags & IS_POW2PS)
761 return info;
762 } else {
763 if (!(info->flags & IS_POW2PS))
764 return info;
765 }
766 } else
767 return info;
768 }
769 }
770
771 return ERR_PTR(-ENODEV);
772}
773
774static struct flash_info *jedec_probe(struct spi_device *spi)
775{
776 int ret;
777 u8 code = OP_READ_ID;
778 u64 jedec;
779 u8 id[sizeof(jedec)] = {0};
780 const unsigned int id_size = 5;
781 struct flash_info *info;
782
783 /*
784 * JEDEC also defines an optional "extended device information"
785 * string for after vendor-specific data, after the three bytes
786 * we use here. Supporting some chips might require using it.
787 *
788 * If the vendor ID isn't Atmel's (0x1f), assume this call failed.
789 * That's not an error; only rev C and newer chips handle it, and
790 * only Atmel sells these chips.
791 */
792 ret = spi_write_then_read(spi, &code, 1, id, id_size);
793 if (ret < 0) {
794 dev_dbg(&spi->dev, "error %d reading JEDEC ID\n", ret);
795 return ERR_PTR(ret);
796 }
797
798 if (id[0] != CFI_MFR_ATMEL)
799 return NULL;
800
801 jedec = be64_to_cpup((__be64 *)id);
802
803 /*
804 * First, try to match device using extended device
805 * information
806 */
807 info = jedec_lookup(spi, jedec >> DATAFLASH_SHIFT_EXTID, true);
808 if (!IS_ERR(info))
809 return info;
810 /*
811 * If that fails, make another pass using regular ID
812 * information
813 */
814 info = jedec_lookup(spi, jedec >> DATAFLASH_SHIFT_ID, false);
815 if (!IS_ERR(info))
816 return info;
817 /*
818 * Treat other chips as errors ... we won't know the right page
819 * size (it might be binary) even when we can tell which density
820 * class is involved (legacy chip id scheme).
821 */
822 dev_warn(&spi->dev, "JEDEC id %016llx not handled\n", jedec);
823 return ERR_PTR(-ENODEV);
824}
825
826/*
827 * Detect and initialize DataFlash device, using JEDEC IDs on newer chips
828 * or else the ID code embedded in the status bits:
829 *
830 * Device Density ID code #Pages PageSize Offset
831 * AT45DB011B 1Mbit (128K) xx0011xx (0x0c) 512 264 9
832 * AT45DB021B 2Mbit (256K) xx0101xx (0x14) 1024 264 9
833 * AT45DB041B 4Mbit (512K) xx0111xx (0x1c) 2048 264 9
834 * AT45DB081B 8Mbit (1M) xx1001xx (0x24) 4096 264 9
835 * AT45DB0161B 16Mbit (2M) xx1011xx (0x2c) 4096 528 10
836 * AT45DB0321B 32Mbit (4M) xx1101xx (0x34) 8192 528 10
837 * AT45DB0642 64Mbit (8M) xx111xxx (0x3c) 8192 1056 11
838 * AT45DB1282 128Mbit (16M) xx0100xx (0x10) 16384 1056 11
839 */
840static int dataflash_probe(struct spi_device *spi)
841{
842 int status;
843 struct flash_info *info;
844
845 /*
846 * Try to detect dataflash by JEDEC ID.
847 * If it succeeds we know we have either a C or D part.
848 * D will support power of 2 pagesize option.
849 * Both support the security register, though with different
850 * write procedures.
851 */
852 info = jedec_probe(spi);
853 if (IS_ERR(info))
854 return PTR_ERR(info);
855 if (info != NULL)
856 return add_dataflash_otp(spi, info->name, info->nr_pages,
857 info->pagesize, info->pageoffset,
858 (info->flags & SUP_POW2PS) ? 'd' : 'c');
859
860 /*
861 * Older chips support only legacy commands, identifing
862 * capacity using bits in the status byte.
863 */
864 status = dataflash_status(spi);
865 if (status <= 0 || status == 0xff) {
866 dev_dbg(&spi->dev, "status error %d\n", status);
867 if (status == 0 || status == 0xff)
868 status = -ENODEV;
869 return status;
870 }
871
872 /* if there's a device there, assume it's dataflash.
873 * board setup should have set spi->max_speed_max to
874 * match f(car) for continuous reads, mode 0 or 3.
875 */
876 switch (status & 0x3c) {
877 case 0x0c: /* 0 0 1 1 x x */
878 status = add_dataflash(spi, "AT45DB011B", 512, 264, 9);
879 break;
880 case 0x14: /* 0 1 0 1 x x */
881 status = add_dataflash(spi, "AT45DB021B", 1024, 264, 9);
882 break;
883 case 0x1c: /* 0 1 1 1 x x */
884 status = add_dataflash(spi, "AT45DB041x", 2048, 264, 9);
885 break;
886 case 0x24: /* 1 0 0 1 x x */
887 status = add_dataflash(spi, "AT45DB081B", 4096, 264, 9);
888 break;
889 case 0x2c: /* 1 0 1 1 x x */
890 status = add_dataflash(spi, "AT45DB161x", 4096, 528, 10);
891 break;
892 case 0x34: /* 1 1 0 1 x x */
893 status = add_dataflash(spi, "AT45DB321x", 8192, 528, 10);
894 break;
895 case 0x38: /* 1 1 1 x x x */
896 case 0x3c:
897 status = add_dataflash(spi, "AT45DB642x", 8192, 1056, 11);
898 break;
899 /* obsolete AT45DB1282 not (yet?) supported */
900 default:
901 dev_info(&spi->dev, "unsupported device (%x)\n",
902 status & 0x3c);
903 status = -ENODEV;
904 }
905
906 if (status < 0)
907 dev_dbg(&spi->dev, "add_dataflash --> %d\n", status);
908
909 return status;
910}
911
912static int dataflash_remove(struct spi_device *spi)
913{
914 struct dataflash *flash = spi_get_drvdata(spi);
915 int status;
916
917 dev_dbg(&spi->dev, "remove\n");
918
919 status = mtd_device_unregister(&flash->mtd);
920 if (status == 0)
921 kfree(flash);
922 return status;
923}
924
925static struct spi_driver dataflash_driver = {
926 .driver = {
927 .name = "mtd_dataflash",
928 .of_match_table = of_match_ptr(dataflash_dt_ids),
929 },
930
931 .probe = dataflash_probe,
932 .remove = dataflash_remove,
933
934 /* FIXME: investigate suspend and resume... */
935};
936
937module_spi_driver(dataflash_driver);
938
939MODULE_LICENSE("GPL");
940MODULE_AUTHOR("Andrew Victor, David Brownell");
941MODULE_DESCRIPTION("MTD DataFlash driver");
942MODULE_ALIAS("spi:mtd_dataflash");
1/*
2 * Atmel AT45xxx DataFlash MTD driver for lightweight SPI framework
3 *
4 * Largely derived from at91_dataflash.c:
5 * Copyright (C) 2003-2005 SAN People (Pty) Ltd
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11*/
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/slab.h>
15#include <linux/delay.h>
16#include <linux/device.h>
17#include <linux/mutex.h>
18#include <linux/err.h>
19#include <linux/math64.h>
20
21#include <linux/spi/spi.h>
22#include <linux/spi/flash.h>
23
24#include <linux/mtd/mtd.h>
25#include <linux/mtd/partitions.h>
26
27
28/*
29 * DataFlash is a kind of SPI flash. Most AT45 chips have two buffers in
30 * each chip, which may be used for double buffered I/O; but this driver
31 * doesn't (yet) use these for any kind of i/o overlap or prefetching.
32 *
33 * Sometimes DataFlash is packaged in MMC-format cards, although the
34 * MMC stack can't (yet?) distinguish between MMC and DataFlash
35 * protocols during enumeration.
36 */
37
38/* reads can bypass the buffers */
39#define OP_READ_CONTINUOUS 0xE8
40#define OP_READ_PAGE 0xD2
41
42/* group B requests can run even while status reports "busy" */
43#define OP_READ_STATUS 0xD7 /* group B */
44
45/* move data between host and buffer */
46#define OP_READ_BUFFER1 0xD4 /* group B */
47#define OP_READ_BUFFER2 0xD6 /* group B */
48#define OP_WRITE_BUFFER1 0x84 /* group B */
49#define OP_WRITE_BUFFER2 0x87 /* group B */
50
51/* erasing flash */
52#define OP_ERASE_PAGE 0x81
53#define OP_ERASE_BLOCK 0x50
54
55/* move data between buffer and flash */
56#define OP_TRANSFER_BUF1 0x53
57#define OP_TRANSFER_BUF2 0x55
58#define OP_MREAD_BUFFER1 0xD4
59#define OP_MREAD_BUFFER2 0xD6
60#define OP_MWERASE_BUFFER1 0x83
61#define OP_MWERASE_BUFFER2 0x86
62#define OP_MWRITE_BUFFER1 0x88 /* sector must be pre-erased */
63#define OP_MWRITE_BUFFER2 0x89 /* sector must be pre-erased */
64
65/* write to buffer, then write-erase to flash */
66#define OP_PROGRAM_VIA_BUF1 0x82
67#define OP_PROGRAM_VIA_BUF2 0x85
68
69/* compare buffer to flash */
70#define OP_COMPARE_BUF1 0x60
71#define OP_COMPARE_BUF2 0x61
72
73/* read flash to buffer, then write-erase to flash */
74#define OP_REWRITE_VIA_BUF1 0x58
75#define OP_REWRITE_VIA_BUF2 0x59
76
77/* newer chips report JEDEC manufacturer and device IDs; chip
78 * serial number and OTP bits; and per-sector writeprotect.
79 */
80#define OP_READ_ID 0x9F
81#define OP_READ_SECURITY 0x77
82#define OP_WRITE_SECURITY_REVC 0x9A
83#define OP_WRITE_SECURITY 0x9B /* revision D */
84
85
86struct dataflash {
87 uint8_t command[4];
88 char name[24];
89
90 unsigned partitioned:1;
91
92 unsigned short page_offset; /* offset in flash address */
93 unsigned int page_size; /* of bytes per page */
94
95 struct mutex lock;
96 struct spi_device *spi;
97
98 struct mtd_info mtd;
99};
100
101/* ......................................................................... */
102
103/*
104 * Return the status of the DataFlash device.
105 */
106static inline int dataflash_status(struct spi_device *spi)
107{
108 /* NOTE: at45db321c over 25 MHz wants to write
109 * a dummy byte after the opcode...
110 */
111 return spi_w8r8(spi, OP_READ_STATUS);
112}
113
114/*
115 * Poll the DataFlash device until it is READY.
116 * This usually takes 5-20 msec or so; more for sector erase.
117 */
118static int dataflash_waitready(struct spi_device *spi)
119{
120 int status;
121
122 for (;;) {
123 status = dataflash_status(spi);
124 if (status < 0) {
125 DEBUG(MTD_DEBUG_LEVEL1, "%s: status %d?\n",
126 dev_name(&spi->dev), status);
127 status = 0;
128 }
129
130 if (status & (1 << 7)) /* RDY/nBSY */
131 return status;
132
133 msleep(3);
134 }
135}
136
137/* ......................................................................... */
138
139/*
140 * Erase pages of flash.
141 */
142static int dataflash_erase(struct mtd_info *mtd, struct erase_info *instr)
143{
144 struct dataflash *priv = mtd->priv;
145 struct spi_device *spi = priv->spi;
146 struct spi_transfer x = { .tx_dma = 0, };
147 struct spi_message msg;
148 unsigned blocksize = priv->page_size << 3;
149 uint8_t *command;
150 uint32_t rem;
151
152 DEBUG(MTD_DEBUG_LEVEL2, "%s: erase addr=0x%llx len 0x%llx\n",
153 dev_name(&spi->dev), (long long)instr->addr,
154 (long long)instr->len);
155
156 /* Sanity checks */
157 if (instr->addr + instr->len > mtd->size)
158 return -EINVAL;
159 div_u64_rem(instr->len, priv->page_size, &rem);
160 if (rem)
161 return -EINVAL;
162 div_u64_rem(instr->addr, priv->page_size, &rem);
163 if (rem)
164 return -EINVAL;
165
166 spi_message_init(&msg);
167
168 x.tx_buf = command = priv->command;
169 x.len = 4;
170 spi_message_add_tail(&x, &msg);
171
172 mutex_lock(&priv->lock);
173 while (instr->len > 0) {
174 unsigned int pageaddr;
175 int status;
176 int do_block;
177
178 /* Calculate flash page address; use block erase (for speed) if
179 * we're at a block boundary and need to erase the whole block.
180 */
181 pageaddr = div_u64(instr->addr, priv->page_size);
182 do_block = (pageaddr & 0x7) == 0 && instr->len >= blocksize;
183 pageaddr = pageaddr << priv->page_offset;
184
185 command[0] = do_block ? OP_ERASE_BLOCK : OP_ERASE_PAGE;
186 command[1] = (uint8_t)(pageaddr >> 16);
187 command[2] = (uint8_t)(pageaddr >> 8);
188 command[3] = 0;
189
190 DEBUG(MTD_DEBUG_LEVEL3, "ERASE %s: (%x) %x %x %x [%i]\n",
191 do_block ? "block" : "page",
192 command[0], command[1], command[2], command[3],
193 pageaddr);
194
195 status = spi_sync(spi, &msg);
196 (void) dataflash_waitready(spi);
197
198 if (status < 0) {
199 printk(KERN_ERR "%s: erase %x, err %d\n",
200 dev_name(&spi->dev), pageaddr, status);
201 /* REVISIT: can retry instr->retries times; or
202 * giveup and instr->fail_addr = instr->addr;
203 */
204 continue;
205 }
206
207 if (do_block) {
208 instr->addr += blocksize;
209 instr->len -= blocksize;
210 } else {
211 instr->addr += priv->page_size;
212 instr->len -= priv->page_size;
213 }
214 }
215 mutex_unlock(&priv->lock);
216
217 /* Inform MTD subsystem that erase is complete */
218 instr->state = MTD_ERASE_DONE;
219 mtd_erase_callback(instr);
220
221 return 0;
222}
223
224/*
225 * Read from the DataFlash device.
226 * from : Start offset in flash device
227 * len : Amount to read
228 * retlen : About of data actually read
229 * buf : Buffer containing the data
230 */
231static int dataflash_read(struct mtd_info *mtd, loff_t from, size_t len,
232 size_t *retlen, u_char *buf)
233{
234 struct dataflash *priv = mtd->priv;
235 struct spi_transfer x[2] = { { .tx_dma = 0, }, };
236 struct spi_message msg;
237 unsigned int addr;
238 uint8_t *command;
239 int status;
240
241 DEBUG(MTD_DEBUG_LEVEL2, "%s: read 0x%x..0x%x\n",
242 dev_name(&priv->spi->dev), (unsigned)from, (unsigned)(from + len));
243
244 *retlen = 0;
245
246 /* Sanity checks */
247 if (!len)
248 return 0;
249 if (from + len > mtd->size)
250 return -EINVAL;
251
252 /* Calculate flash page/byte address */
253 addr = (((unsigned)from / priv->page_size) << priv->page_offset)
254 + ((unsigned)from % priv->page_size);
255
256 command = priv->command;
257
258 DEBUG(MTD_DEBUG_LEVEL3, "READ: (%x) %x %x %x\n",
259 command[0], command[1], command[2], command[3]);
260
261 spi_message_init(&msg);
262
263 x[0].tx_buf = command;
264 x[0].len = 8;
265 spi_message_add_tail(&x[0], &msg);
266
267 x[1].rx_buf = buf;
268 x[1].len = len;
269 spi_message_add_tail(&x[1], &msg);
270
271 mutex_lock(&priv->lock);
272
273 /* Continuous read, max clock = f(car) which may be less than
274 * the peak rate available. Some chips support commands with
275 * fewer "don't care" bytes. Both buffers stay unchanged.
276 */
277 command[0] = OP_READ_CONTINUOUS;
278 command[1] = (uint8_t)(addr >> 16);
279 command[2] = (uint8_t)(addr >> 8);
280 command[3] = (uint8_t)(addr >> 0);
281 /* plus 4 "don't care" bytes */
282
283 status = spi_sync(priv->spi, &msg);
284 mutex_unlock(&priv->lock);
285
286 if (status >= 0) {
287 *retlen = msg.actual_length - 8;
288 status = 0;
289 } else
290 DEBUG(MTD_DEBUG_LEVEL1, "%s: read %x..%x --> %d\n",
291 dev_name(&priv->spi->dev),
292 (unsigned)from, (unsigned)(from + len),
293 status);
294 return status;
295}
296
297/*
298 * Write to the DataFlash device.
299 * to : Start offset in flash device
300 * len : Amount to write
301 * retlen : Amount of data actually written
302 * buf : Buffer containing the data
303 */
304static int dataflash_write(struct mtd_info *mtd, loff_t to, size_t len,
305 size_t * retlen, const u_char * buf)
306{
307 struct dataflash *priv = mtd->priv;
308 struct spi_device *spi = priv->spi;
309 struct spi_transfer x[2] = { { .tx_dma = 0, }, };
310 struct spi_message msg;
311 unsigned int pageaddr, addr, offset, writelen;
312 size_t remaining = len;
313 u_char *writebuf = (u_char *) buf;
314 int status = -EINVAL;
315 uint8_t *command;
316
317 DEBUG(MTD_DEBUG_LEVEL2, "%s: write 0x%x..0x%x\n",
318 dev_name(&spi->dev), (unsigned)to, (unsigned)(to + len));
319
320 *retlen = 0;
321
322 /* Sanity checks */
323 if (!len)
324 return 0;
325 if ((to + len) > mtd->size)
326 return -EINVAL;
327
328 spi_message_init(&msg);
329
330 x[0].tx_buf = command = priv->command;
331 x[0].len = 4;
332 spi_message_add_tail(&x[0], &msg);
333
334 pageaddr = ((unsigned)to / priv->page_size);
335 offset = ((unsigned)to % priv->page_size);
336 if (offset + len > priv->page_size)
337 writelen = priv->page_size - offset;
338 else
339 writelen = len;
340
341 mutex_lock(&priv->lock);
342 while (remaining > 0) {
343 DEBUG(MTD_DEBUG_LEVEL3, "write @ %i:%i len=%i\n",
344 pageaddr, offset, writelen);
345
346 /* REVISIT:
347 * (a) each page in a sector must be rewritten at least
348 * once every 10K sibling erase/program operations.
349 * (b) for pages that are already erased, we could
350 * use WRITE+MWRITE not PROGRAM for ~30% speedup.
351 * (c) WRITE to buffer could be done while waiting for
352 * a previous MWRITE/MWERASE to complete ...
353 * (d) error handling here seems to be mostly missing.
354 *
355 * Two persistent bits per page, plus a per-sector counter,
356 * could support (a) and (b) ... we might consider using
357 * the second half of sector zero, which is just one block,
358 * to track that state. (On AT91, that sector should also
359 * support boot-from-DataFlash.)
360 */
361
362 addr = pageaddr << priv->page_offset;
363
364 /* (1) Maybe transfer partial page to Buffer1 */
365 if (writelen != priv->page_size) {
366 command[0] = OP_TRANSFER_BUF1;
367 command[1] = (addr & 0x00FF0000) >> 16;
368 command[2] = (addr & 0x0000FF00) >> 8;
369 command[3] = 0;
370
371 DEBUG(MTD_DEBUG_LEVEL3, "TRANSFER: (%x) %x %x %x\n",
372 command[0], command[1], command[2], command[3]);
373
374 status = spi_sync(spi, &msg);
375 if (status < 0)
376 DEBUG(MTD_DEBUG_LEVEL1, "%s: xfer %u -> %d \n",
377 dev_name(&spi->dev), addr, status);
378
379 (void) dataflash_waitready(priv->spi);
380 }
381
382 /* (2) Program full page via Buffer1 */
383 addr += offset;
384 command[0] = OP_PROGRAM_VIA_BUF1;
385 command[1] = (addr & 0x00FF0000) >> 16;
386 command[2] = (addr & 0x0000FF00) >> 8;
387 command[3] = (addr & 0x000000FF);
388
389 DEBUG(MTD_DEBUG_LEVEL3, "PROGRAM: (%x) %x %x %x\n",
390 command[0], command[1], command[2], command[3]);
391
392 x[1].tx_buf = writebuf;
393 x[1].len = writelen;
394 spi_message_add_tail(x + 1, &msg);
395 status = spi_sync(spi, &msg);
396 spi_transfer_del(x + 1);
397 if (status < 0)
398 DEBUG(MTD_DEBUG_LEVEL1, "%s: pgm %u/%u -> %d \n",
399 dev_name(&spi->dev), addr, writelen, status);
400
401 (void) dataflash_waitready(priv->spi);
402
403
404#ifdef CONFIG_MTD_DATAFLASH_WRITE_VERIFY
405
406 /* (3) Compare to Buffer1 */
407 addr = pageaddr << priv->page_offset;
408 command[0] = OP_COMPARE_BUF1;
409 command[1] = (addr & 0x00FF0000) >> 16;
410 command[2] = (addr & 0x0000FF00) >> 8;
411 command[3] = 0;
412
413 DEBUG(MTD_DEBUG_LEVEL3, "COMPARE: (%x) %x %x %x\n",
414 command[0], command[1], command[2], command[3]);
415
416 status = spi_sync(spi, &msg);
417 if (status < 0)
418 DEBUG(MTD_DEBUG_LEVEL1, "%s: compare %u -> %d \n",
419 dev_name(&spi->dev), addr, status);
420
421 status = dataflash_waitready(priv->spi);
422
423 /* Check result of the compare operation */
424 if (status & (1 << 6)) {
425 printk(KERN_ERR "%s: compare page %u, err %d\n",
426 dev_name(&spi->dev), pageaddr, status);
427 remaining = 0;
428 status = -EIO;
429 break;
430 } else
431 status = 0;
432
433#endif /* CONFIG_MTD_DATAFLASH_WRITE_VERIFY */
434
435 remaining = remaining - writelen;
436 pageaddr++;
437 offset = 0;
438 writebuf += writelen;
439 *retlen += writelen;
440
441 if (remaining > priv->page_size)
442 writelen = priv->page_size;
443 else
444 writelen = remaining;
445 }
446 mutex_unlock(&priv->lock);
447
448 return status;
449}
450
451/* ......................................................................... */
452
453#ifdef CONFIG_MTD_DATAFLASH_OTP
454
455static int dataflash_get_otp_info(struct mtd_info *mtd,
456 struct otp_info *info, size_t len)
457{
458 /* Report both blocks as identical: bytes 0..64, locked.
459 * Unless the user block changed from all-ones, we can't
460 * tell whether it's still writable; so we assume it isn't.
461 */
462 info->start = 0;
463 info->length = 64;
464 info->locked = 1;
465 return sizeof(*info);
466}
467
468static ssize_t otp_read(struct spi_device *spi, unsigned base,
469 uint8_t *buf, loff_t off, size_t len)
470{
471 struct spi_message m;
472 size_t l;
473 uint8_t *scratch;
474 struct spi_transfer t;
475 int status;
476
477 if (off > 64)
478 return -EINVAL;
479
480 if ((off + len) > 64)
481 len = 64 - off;
482 if (len == 0)
483 return len;
484
485 spi_message_init(&m);
486
487 l = 4 + base + off + len;
488 scratch = kzalloc(l, GFP_KERNEL);
489 if (!scratch)
490 return -ENOMEM;
491
492 /* OUT: OP_READ_SECURITY, 3 don't-care bytes, zeroes
493 * IN: ignore 4 bytes, data bytes 0..N (max 127)
494 */
495 scratch[0] = OP_READ_SECURITY;
496
497 memset(&t, 0, sizeof t);
498 t.tx_buf = scratch;
499 t.rx_buf = scratch;
500 t.len = l;
501 spi_message_add_tail(&t, &m);
502
503 dataflash_waitready(spi);
504
505 status = spi_sync(spi, &m);
506 if (status >= 0) {
507 memcpy(buf, scratch + 4 + base + off, len);
508 status = len;
509 }
510
511 kfree(scratch);
512 return status;
513}
514
515static int dataflash_read_fact_otp(struct mtd_info *mtd,
516 loff_t from, size_t len, size_t *retlen, u_char *buf)
517{
518 struct dataflash *priv = mtd->priv;
519 int status;
520
521 /* 64 bytes, from 0..63 ... start at 64 on-chip */
522 mutex_lock(&priv->lock);
523 status = otp_read(priv->spi, 64, buf, from, len);
524 mutex_unlock(&priv->lock);
525
526 if (status < 0)
527 return status;
528 *retlen = status;
529 return 0;
530}
531
532static int dataflash_read_user_otp(struct mtd_info *mtd,
533 loff_t from, size_t len, size_t *retlen, u_char *buf)
534{
535 struct dataflash *priv = mtd->priv;
536 int status;
537
538 /* 64 bytes, from 0..63 ... start at 0 on-chip */
539 mutex_lock(&priv->lock);
540 status = otp_read(priv->spi, 0, buf, from, len);
541 mutex_unlock(&priv->lock);
542
543 if (status < 0)
544 return status;
545 *retlen = status;
546 return 0;
547}
548
549static int dataflash_write_user_otp(struct mtd_info *mtd,
550 loff_t from, size_t len, size_t *retlen, u_char *buf)
551{
552 struct spi_message m;
553 const size_t l = 4 + 64;
554 uint8_t *scratch;
555 struct spi_transfer t;
556 struct dataflash *priv = mtd->priv;
557 int status;
558
559 if (len > 64)
560 return -EINVAL;
561
562 /* Strictly speaking, we *could* truncate the write ... but
563 * let's not do that for the only write that's ever possible.
564 */
565 if ((from + len) > 64)
566 return -EINVAL;
567
568 /* OUT: OP_WRITE_SECURITY, 3 zeroes, 64 data-or-zero bytes
569 * IN: ignore all
570 */
571 scratch = kzalloc(l, GFP_KERNEL);
572 if (!scratch)
573 return -ENOMEM;
574 scratch[0] = OP_WRITE_SECURITY;
575 memcpy(scratch + 4 + from, buf, len);
576
577 spi_message_init(&m);
578
579 memset(&t, 0, sizeof t);
580 t.tx_buf = scratch;
581 t.len = l;
582 spi_message_add_tail(&t, &m);
583
584 /* Write the OTP bits, if they've not yet been written.
585 * This modifies SRAM buffer1.
586 */
587 mutex_lock(&priv->lock);
588 dataflash_waitready(priv->spi);
589 status = spi_sync(priv->spi, &m);
590 mutex_unlock(&priv->lock);
591
592 kfree(scratch);
593
594 if (status >= 0) {
595 status = 0;
596 *retlen = len;
597 }
598 return status;
599}
600
601static char *otp_setup(struct mtd_info *device, char revision)
602{
603 device->get_fact_prot_info = dataflash_get_otp_info;
604 device->read_fact_prot_reg = dataflash_read_fact_otp;
605 device->get_user_prot_info = dataflash_get_otp_info;
606 device->read_user_prot_reg = dataflash_read_user_otp;
607
608 /* rev c parts (at45db321c and at45db1281 only!) use a
609 * different write procedure; not (yet?) implemented.
610 */
611 if (revision > 'c')
612 device->write_user_prot_reg = dataflash_write_user_otp;
613
614 return ", OTP";
615}
616
617#else
618
619static char *otp_setup(struct mtd_info *device, char revision)
620{
621 return " (OTP)";
622}
623
624#endif
625
626/* ......................................................................... */
627
628/*
629 * Register DataFlash device with MTD subsystem.
630 */
631static int __devinit
632add_dataflash_otp(struct spi_device *spi, char *name,
633 int nr_pages, int pagesize, int pageoffset, char revision)
634{
635 struct dataflash *priv;
636 struct mtd_info *device;
637 struct flash_platform_data *pdata = spi->dev.platform_data;
638 char *otp_tag = "";
639 int err = 0;
640 struct mtd_partition *parts;
641 int nr_parts = 0;
642
643 priv = kzalloc(sizeof *priv, GFP_KERNEL);
644 if (!priv)
645 return -ENOMEM;
646
647 mutex_init(&priv->lock);
648 priv->spi = spi;
649 priv->page_size = pagesize;
650 priv->page_offset = pageoffset;
651
652 /* name must be usable with cmdlinepart */
653 sprintf(priv->name, "spi%d.%d-%s",
654 spi->master->bus_num, spi->chip_select,
655 name);
656
657 device = &priv->mtd;
658 device->name = (pdata && pdata->name) ? pdata->name : priv->name;
659 device->size = nr_pages * pagesize;
660 device->erasesize = pagesize;
661 device->writesize = pagesize;
662 device->owner = THIS_MODULE;
663 device->type = MTD_DATAFLASH;
664 device->flags = MTD_WRITEABLE;
665 device->erase = dataflash_erase;
666 device->read = dataflash_read;
667 device->write = dataflash_write;
668 device->priv = priv;
669
670 device->dev.parent = &spi->dev;
671
672 if (revision >= 'c')
673 otp_tag = otp_setup(device, revision);
674
675 dev_info(&spi->dev, "%s (%lld KBytes) pagesize %d bytes%s\n",
676 name, (long long)((device->size + 1023) >> 10),
677 pagesize, otp_tag);
678 dev_set_drvdata(&spi->dev, priv);
679
680 if (mtd_has_cmdlinepart()) {
681 static const char *part_probes[] = { "cmdlinepart", NULL, };
682
683 nr_parts = parse_mtd_partitions(device, part_probes, &parts,
684 0);
685 }
686
687 if (nr_parts <= 0 && pdata && pdata->parts) {
688 parts = pdata->parts;
689 nr_parts = pdata->nr_parts;
690 }
691
692 if (nr_parts > 0) {
693 priv->partitioned = 1;
694 err = mtd_device_register(device, parts, nr_parts);
695 goto out;
696 }
697
698 if (mtd_device_register(device, NULL, 0) == 1)
699 err = -ENODEV;
700
701out:
702 if (!err)
703 return 0;
704
705 dev_set_drvdata(&spi->dev, NULL);
706 kfree(priv);
707 return err;
708}
709
710static inline int __devinit
711add_dataflash(struct spi_device *spi, char *name,
712 int nr_pages, int pagesize, int pageoffset)
713{
714 return add_dataflash_otp(spi, name, nr_pages, pagesize,
715 pageoffset, 0);
716}
717
718struct flash_info {
719 char *name;
720
721 /* JEDEC id has a high byte of zero plus three data bytes:
722 * the manufacturer id, then a two byte device id.
723 */
724 uint32_t jedec_id;
725
726 /* The size listed here is what works with OP_ERASE_PAGE. */
727 unsigned nr_pages;
728 uint16_t pagesize;
729 uint16_t pageoffset;
730
731 uint16_t flags;
732#define SUP_POW2PS 0x0002 /* supports 2^N byte pages */
733#define IS_POW2PS 0x0001 /* uses 2^N byte pages */
734};
735
736static struct flash_info __devinitdata dataflash_data [] = {
737
738 /*
739 * NOTE: chips with SUP_POW2PS (rev D and up) need two entries,
740 * one with IS_POW2PS and the other without. The entry with the
741 * non-2^N byte page size can't name exact chip revisions without
742 * losing backwards compatibility for cmdlinepart.
743 *
744 * These newer chips also support 128-byte security registers (with
745 * 64 bytes one-time-programmable) and software write-protection.
746 */
747 { "AT45DB011B", 0x1f2200, 512, 264, 9, SUP_POW2PS},
748 { "at45db011d", 0x1f2200, 512, 256, 8, SUP_POW2PS | IS_POW2PS},
749
750 { "AT45DB021B", 0x1f2300, 1024, 264, 9, SUP_POW2PS},
751 { "at45db021d", 0x1f2300, 1024, 256, 8, SUP_POW2PS | IS_POW2PS},
752
753 { "AT45DB041x", 0x1f2400, 2048, 264, 9, SUP_POW2PS},
754 { "at45db041d", 0x1f2400, 2048, 256, 8, SUP_POW2PS | IS_POW2PS},
755
756 { "AT45DB081B", 0x1f2500, 4096, 264, 9, SUP_POW2PS},
757 { "at45db081d", 0x1f2500, 4096, 256, 8, SUP_POW2PS | IS_POW2PS},
758
759 { "AT45DB161x", 0x1f2600, 4096, 528, 10, SUP_POW2PS},
760 { "at45db161d", 0x1f2600, 4096, 512, 9, SUP_POW2PS | IS_POW2PS},
761
762 { "AT45DB321x", 0x1f2700, 8192, 528, 10, 0}, /* rev C */
763
764 { "AT45DB321x", 0x1f2701, 8192, 528, 10, SUP_POW2PS},
765 { "at45db321d", 0x1f2701, 8192, 512, 9, SUP_POW2PS | IS_POW2PS},
766
767 { "AT45DB642x", 0x1f2800, 8192, 1056, 11, SUP_POW2PS},
768 { "at45db642d", 0x1f2800, 8192, 1024, 10, SUP_POW2PS | IS_POW2PS},
769};
770
771static struct flash_info *__devinit jedec_probe(struct spi_device *spi)
772{
773 int tmp;
774 uint8_t code = OP_READ_ID;
775 uint8_t id[3];
776 uint32_t jedec;
777 struct flash_info *info;
778 int status;
779
780 /* JEDEC also defines an optional "extended device information"
781 * string for after vendor-specific data, after the three bytes
782 * we use here. Supporting some chips might require using it.
783 *
784 * If the vendor ID isn't Atmel's (0x1f), assume this call failed.
785 * That's not an error; only rev C and newer chips handle it, and
786 * only Atmel sells these chips.
787 */
788 tmp = spi_write_then_read(spi, &code, 1, id, 3);
789 if (tmp < 0) {
790 DEBUG(MTD_DEBUG_LEVEL0, "%s: error %d reading JEDEC ID\n",
791 dev_name(&spi->dev), tmp);
792 return ERR_PTR(tmp);
793 }
794 if (id[0] != 0x1f)
795 return NULL;
796
797 jedec = id[0];
798 jedec = jedec << 8;
799 jedec |= id[1];
800 jedec = jedec << 8;
801 jedec |= id[2];
802
803 for (tmp = 0, info = dataflash_data;
804 tmp < ARRAY_SIZE(dataflash_data);
805 tmp++, info++) {
806 if (info->jedec_id == jedec) {
807 DEBUG(MTD_DEBUG_LEVEL1, "%s: OTP, sector protect%s\n",
808 dev_name(&spi->dev),
809 (info->flags & SUP_POW2PS)
810 ? ", binary pagesize" : ""
811 );
812 if (info->flags & SUP_POW2PS) {
813 status = dataflash_status(spi);
814 if (status < 0) {
815 DEBUG(MTD_DEBUG_LEVEL1,
816 "%s: status error %d\n",
817 dev_name(&spi->dev), status);
818 return ERR_PTR(status);
819 }
820 if (status & 0x1) {
821 if (info->flags & IS_POW2PS)
822 return info;
823 } else {
824 if (!(info->flags & IS_POW2PS))
825 return info;
826 }
827 } else
828 return info;
829 }
830 }
831
832 /*
833 * Treat other chips as errors ... we won't know the right page
834 * size (it might be binary) even when we can tell which density
835 * class is involved (legacy chip id scheme).
836 */
837 dev_warn(&spi->dev, "JEDEC id %06x not handled\n", jedec);
838 return ERR_PTR(-ENODEV);
839}
840
841/*
842 * Detect and initialize DataFlash device, using JEDEC IDs on newer chips
843 * or else the ID code embedded in the status bits:
844 *
845 * Device Density ID code #Pages PageSize Offset
846 * AT45DB011B 1Mbit (128K) xx0011xx (0x0c) 512 264 9
847 * AT45DB021B 2Mbit (256K) xx0101xx (0x14) 1024 264 9
848 * AT45DB041B 4Mbit (512K) xx0111xx (0x1c) 2048 264 9
849 * AT45DB081B 8Mbit (1M) xx1001xx (0x24) 4096 264 9
850 * AT45DB0161B 16Mbit (2M) xx1011xx (0x2c) 4096 528 10
851 * AT45DB0321B 32Mbit (4M) xx1101xx (0x34) 8192 528 10
852 * AT45DB0642 64Mbit (8M) xx111xxx (0x3c) 8192 1056 11
853 * AT45DB1282 128Mbit (16M) xx0100xx (0x10) 16384 1056 11
854 */
855static int __devinit dataflash_probe(struct spi_device *spi)
856{
857 int status;
858 struct flash_info *info;
859
860 /*
861 * Try to detect dataflash by JEDEC ID.
862 * If it succeeds we know we have either a C or D part.
863 * D will support power of 2 pagesize option.
864 * Both support the security register, though with different
865 * write procedures.
866 */
867 info = jedec_probe(spi);
868 if (IS_ERR(info))
869 return PTR_ERR(info);
870 if (info != NULL)
871 return add_dataflash_otp(spi, info->name, info->nr_pages,
872 info->pagesize, info->pageoffset,
873 (info->flags & SUP_POW2PS) ? 'd' : 'c');
874
875 /*
876 * Older chips support only legacy commands, identifing
877 * capacity using bits in the status byte.
878 */
879 status = dataflash_status(spi);
880 if (status <= 0 || status == 0xff) {
881 DEBUG(MTD_DEBUG_LEVEL1, "%s: status error %d\n",
882 dev_name(&spi->dev), status);
883 if (status == 0 || status == 0xff)
884 status = -ENODEV;
885 return status;
886 }
887
888 /* if there's a device there, assume it's dataflash.
889 * board setup should have set spi->max_speed_max to
890 * match f(car) for continuous reads, mode 0 or 3.
891 */
892 switch (status & 0x3c) {
893 case 0x0c: /* 0 0 1 1 x x */
894 status = add_dataflash(spi, "AT45DB011B", 512, 264, 9);
895 break;
896 case 0x14: /* 0 1 0 1 x x */
897 status = add_dataflash(spi, "AT45DB021B", 1024, 264, 9);
898 break;
899 case 0x1c: /* 0 1 1 1 x x */
900 status = add_dataflash(spi, "AT45DB041x", 2048, 264, 9);
901 break;
902 case 0x24: /* 1 0 0 1 x x */
903 status = add_dataflash(spi, "AT45DB081B", 4096, 264, 9);
904 break;
905 case 0x2c: /* 1 0 1 1 x x */
906 status = add_dataflash(spi, "AT45DB161x", 4096, 528, 10);
907 break;
908 case 0x34: /* 1 1 0 1 x x */
909 status = add_dataflash(spi, "AT45DB321x", 8192, 528, 10);
910 break;
911 case 0x38: /* 1 1 1 x x x */
912 case 0x3c:
913 status = add_dataflash(spi, "AT45DB642x", 8192, 1056, 11);
914 break;
915 /* obsolete AT45DB1282 not (yet?) supported */
916 default:
917 DEBUG(MTD_DEBUG_LEVEL1, "%s: unsupported device (%x)\n",
918 dev_name(&spi->dev), status & 0x3c);
919 status = -ENODEV;
920 }
921
922 if (status < 0)
923 DEBUG(MTD_DEBUG_LEVEL1, "%s: add_dataflash --> %d\n",
924 dev_name(&spi->dev), status);
925
926 return status;
927}
928
929static int __devexit dataflash_remove(struct spi_device *spi)
930{
931 struct dataflash *flash = dev_get_drvdata(&spi->dev);
932 int status;
933
934 DEBUG(MTD_DEBUG_LEVEL1, "%s: remove\n", dev_name(&spi->dev));
935
936 status = mtd_device_unregister(&flash->mtd);
937 if (status == 0) {
938 dev_set_drvdata(&spi->dev, NULL);
939 kfree(flash);
940 }
941 return status;
942}
943
944static struct spi_driver dataflash_driver = {
945 .driver = {
946 .name = "mtd_dataflash",
947 .bus = &spi_bus_type,
948 .owner = THIS_MODULE,
949 },
950
951 .probe = dataflash_probe,
952 .remove = __devexit_p(dataflash_remove),
953
954 /* FIXME: investigate suspend and resume... */
955};
956
957static int __init dataflash_init(void)
958{
959 return spi_register_driver(&dataflash_driver);
960}
961module_init(dataflash_init);
962
963static void __exit dataflash_exit(void)
964{
965 spi_unregister_driver(&dataflash_driver);
966}
967module_exit(dataflash_exit);
968
969
970MODULE_LICENSE("GPL");
971MODULE_AUTHOR("Andrew Victor, David Brownell");
972MODULE_DESCRIPTION("MTD DataFlash driver");
973MODULE_ALIAS("spi:mtd_dataflash");