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

source code of linux/drivers/mtd/devices/mtd_dataflash.c