xref: /linux/drivers/mtd/spi-nor/core.c (revision bb1f9e39c1bf7349405a48d2c77087dff6cea32b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Based on m25p80.c, by Mike Lavender (mike@steroidmicros.com), with
4  * influence from lart.c (Abraham Van Der Merwe) and mtd_dataflash.c
5  *
6  * Copyright (C) 2005, Intec Automation Inc.
7  * Copyright (C) 2014, Freescale Semiconductor, Inc.
8  */
9 
10 #include <linux/err.h>
11 #include <linux/errno.h>
12 #include <linux/delay.h>
13 #include <linux/device.h>
14 #include <linux/math64.h>
15 #include <linux/module.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/spi-nor.h>
18 #include <linux/mutex.h>
19 #include <linux/of_platform.h>
20 #include <linux/sched/task_stack.h>
21 #include <linux/sizes.h>
22 #include <linux/slab.h>
23 #include <linux/spi/flash.h>
24 
25 #include "core.h"
26 
27 /* Define max times to check status register before we give up. */
28 
29 /*
30  * For everything but full-chip erase; probably could be much smaller, but kept
31  * around for safety for now
32  */
33 #define DEFAULT_READY_WAIT_JIFFIES		(40UL * HZ)
34 
35 /*
36  * For full-chip erase, calibrated to a 2MB flash (M25P16); should be scaled up
37  * for larger flash
38  */
39 #define CHIP_ERASE_2MB_READY_WAIT_JIFFIES	(40UL * HZ)
40 
41 #define SPI_NOR_MAX_ADDR_NBYTES	4
42 
43 #define SPI_NOR_SRST_SLEEP_MIN 200
44 #define SPI_NOR_SRST_SLEEP_MAX 400
45 
46 /**
47  * spi_nor_get_cmd_ext() - Get the command opcode extension based on the
48  *			   extension type.
49  * @nor:		pointer to a 'struct spi_nor'
50  * @op:			pointer to the 'struct spi_mem_op' whose properties
51  *			need to be initialized.
52  *
53  * Right now, only "repeat" and "invert" are supported.
54  *
55  * Return: The opcode extension.
56  */
57 static u8 spi_nor_get_cmd_ext(const struct spi_nor *nor,
58 			      const struct spi_mem_op *op)
59 {
60 	switch (nor->cmd_ext_type) {
61 	case SPI_NOR_EXT_INVERT:
62 		return ~op->cmd.opcode;
63 
64 	case SPI_NOR_EXT_REPEAT:
65 		return op->cmd.opcode;
66 
67 	default:
68 		dev_err(nor->dev, "Unknown command extension type\n");
69 		return 0;
70 	}
71 }
72 
73 /**
74  * spi_nor_spimem_setup_op() - Set up common properties of a spi-mem op.
75  * @nor:		pointer to a 'struct spi_nor'
76  * @op:			pointer to the 'struct spi_mem_op' whose properties
77  *			need to be initialized.
78  * @proto:		the protocol from which the properties need to be set.
79  */
80 void spi_nor_spimem_setup_op(const struct spi_nor *nor,
81 			     struct spi_mem_op *op,
82 			     const enum spi_nor_protocol proto)
83 {
84 	u8 ext;
85 
86 	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(proto);
87 
88 	if (op->addr.nbytes)
89 		op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
90 
91 	if (op->dummy.nbytes)
92 		op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
93 
94 	if (op->data.nbytes)
95 		op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
96 
97 	if (spi_nor_protocol_is_dtr(proto)) {
98 		/*
99 		 * SPIMEM supports mixed DTR modes, but right now we can only
100 		 * have all phases either DTR or STR. IOW, SPIMEM can have
101 		 * something like 4S-4D-4D, but SPI NOR can't. So, set all 4
102 		 * phases to either DTR or STR.
103 		 */
104 		op->cmd.dtr = true;
105 		op->addr.dtr = true;
106 		op->dummy.dtr = true;
107 		op->data.dtr = true;
108 
109 		/* 2 bytes per clock cycle in DTR mode. */
110 		op->dummy.nbytes *= 2;
111 
112 		ext = spi_nor_get_cmd_ext(nor, op);
113 		op->cmd.opcode = (op->cmd.opcode << 8) | ext;
114 		op->cmd.nbytes = 2;
115 	}
116 }
117 
118 /**
119  * spi_nor_spimem_bounce() - check if a bounce buffer is needed for the data
120  *                           transfer
121  * @nor:        pointer to 'struct spi_nor'
122  * @op:         pointer to 'struct spi_mem_op' template for transfer
123  *
124  * If we have to use the bounce buffer, the data field in @op will be updated.
125  *
126  * Return: true if the bounce buffer is needed, false if not
127  */
128 static bool spi_nor_spimem_bounce(struct spi_nor *nor, struct spi_mem_op *op)
129 {
130 	/* op->data.buf.in occupies the same memory as op->data.buf.out */
131 	if (object_is_on_stack(op->data.buf.in) ||
132 	    !virt_addr_valid(op->data.buf.in)) {
133 		if (op->data.nbytes > nor->bouncebuf_size)
134 			op->data.nbytes = nor->bouncebuf_size;
135 		op->data.buf.in = nor->bouncebuf;
136 		return true;
137 	}
138 
139 	return false;
140 }
141 
142 /**
143  * spi_nor_spimem_exec_op() - execute a memory operation
144  * @nor:        pointer to 'struct spi_nor'
145  * @op:         pointer to 'struct spi_mem_op' template for transfer
146  *
147  * Return: 0 on success, -error otherwise.
148  */
149 static int spi_nor_spimem_exec_op(struct spi_nor *nor, struct spi_mem_op *op)
150 {
151 	int error;
152 
153 	error = spi_mem_adjust_op_size(nor->spimem, op);
154 	if (error)
155 		return error;
156 
157 	return spi_mem_exec_op(nor->spimem, op);
158 }
159 
160 int spi_nor_controller_ops_read_reg(struct spi_nor *nor, u8 opcode,
161 				    u8 *buf, size_t len)
162 {
163 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
164 		return -EOPNOTSUPP;
165 
166 	return nor->controller_ops->read_reg(nor, opcode, buf, len);
167 }
168 
169 int spi_nor_controller_ops_write_reg(struct spi_nor *nor, u8 opcode,
170 				     const u8 *buf, size_t len)
171 {
172 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
173 		return -EOPNOTSUPP;
174 
175 	return nor->controller_ops->write_reg(nor, opcode, buf, len);
176 }
177 
178 static int spi_nor_controller_ops_erase(struct spi_nor *nor, loff_t offs)
179 {
180 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
181 		return -EOPNOTSUPP;
182 
183 	return nor->controller_ops->erase(nor, offs);
184 }
185 
186 /**
187  * spi_nor_spimem_read_data() - read data from flash's memory region via
188  *                              spi-mem
189  * @nor:        pointer to 'struct spi_nor'
190  * @from:       offset to read from
191  * @len:        number of bytes to read
192  * @buf:        pointer to dst buffer
193  *
194  * Return: number of bytes read successfully, -errno otherwise
195  */
196 static ssize_t spi_nor_spimem_read_data(struct spi_nor *nor, loff_t from,
197 					size_t len, u8 *buf)
198 {
199 	struct spi_mem_op op =
200 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
201 			   SPI_MEM_OP_ADDR(nor->addr_nbytes, from, 0),
202 			   SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
203 			   SPI_MEM_OP_DATA_IN(len, buf, 0));
204 	bool usebouncebuf;
205 	ssize_t nbytes;
206 	int error;
207 
208 	spi_nor_spimem_setup_op(nor, &op, nor->read_proto);
209 
210 	/* convert the dummy cycles to the number of bytes */
211 	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
212 	if (spi_nor_protocol_is_dtr(nor->read_proto))
213 		op.dummy.nbytes *= 2;
214 
215 	usebouncebuf = spi_nor_spimem_bounce(nor, &op);
216 
217 	if (nor->dirmap.rdesc) {
218 		nbytes = spi_mem_dirmap_read(nor->dirmap.rdesc, op.addr.val,
219 					     op.data.nbytes, op.data.buf.in);
220 	} else {
221 		error = spi_nor_spimem_exec_op(nor, &op);
222 		if (error)
223 			return error;
224 		nbytes = op.data.nbytes;
225 	}
226 
227 	if (usebouncebuf && nbytes > 0)
228 		memcpy(buf, op.data.buf.in, nbytes);
229 
230 	return nbytes;
231 }
232 
233 /**
234  * spi_nor_read_data() - read data from flash memory
235  * @nor:        pointer to 'struct spi_nor'
236  * @from:       offset to read from
237  * @len:        number of bytes to read
238  * @buf:        pointer to dst buffer
239  *
240  * Return: number of bytes read successfully, -errno otherwise
241  */
242 ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len, u8 *buf)
243 {
244 	if (nor->spimem)
245 		return spi_nor_spimem_read_data(nor, from, len, buf);
246 
247 	return nor->controller_ops->read(nor, from, len, buf);
248 }
249 
250 /**
251  * spi_nor_spimem_write_data() - write data to flash memory via
252  *                               spi-mem
253  * @nor:        pointer to 'struct spi_nor'
254  * @to:         offset to write to
255  * @len:        number of bytes to write
256  * @buf:        pointer to src buffer
257  *
258  * Return: number of bytes written successfully, -errno otherwise
259  */
260 static ssize_t spi_nor_spimem_write_data(struct spi_nor *nor, loff_t to,
261 					 size_t len, const u8 *buf)
262 {
263 	struct spi_mem_op op =
264 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
265 			   SPI_MEM_OP_ADDR(nor->addr_nbytes, to, 0),
266 			   SPI_MEM_OP_NO_DUMMY,
267 			   SPI_MEM_OP_DATA_OUT(len, buf, 0));
268 	ssize_t nbytes;
269 	int error;
270 
271 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
272 		op.addr.nbytes = 0;
273 
274 	spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
275 
276 	if (spi_nor_spimem_bounce(nor, &op))
277 		memcpy(nor->bouncebuf, buf, op.data.nbytes);
278 
279 	if (nor->dirmap.wdesc) {
280 		nbytes = spi_mem_dirmap_write(nor->dirmap.wdesc, op.addr.val,
281 					      op.data.nbytes, op.data.buf.out);
282 	} else {
283 		error = spi_nor_spimem_exec_op(nor, &op);
284 		if (error)
285 			return error;
286 		nbytes = op.data.nbytes;
287 	}
288 
289 	return nbytes;
290 }
291 
292 /**
293  * spi_nor_write_data() - write data to flash memory
294  * @nor:        pointer to 'struct spi_nor'
295  * @to:         offset to write to
296  * @len:        number of bytes to write
297  * @buf:        pointer to src buffer
298  *
299  * Return: number of bytes written successfully, -errno otherwise
300  */
301 ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
302 			   const u8 *buf)
303 {
304 	if (nor->spimem)
305 		return spi_nor_spimem_write_data(nor, to, len, buf);
306 
307 	return nor->controller_ops->write(nor, to, len, buf);
308 }
309 
310 /**
311  * spi_nor_read_any_reg() - read any register from flash memory, nonvolatile or
312  * volatile.
313  * @nor:        pointer to 'struct spi_nor'.
314  * @op:		SPI memory operation. op->data.buf must be DMA-able.
315  * @proto:	SPI protocol to use for the register operation.
316  *
317  * Return: zero on success, -errno otherwise
318  */
319 int spi_nor_read_any_reg(struct spi_nor *nor, struct spi_mem_op *op,
320 			 enum spi_nor_protocol proto)
321 {
322 	if (!nor->spimem)
323 		return -EOPNOTSUPP;
324 
325 	spi_nor_spimem_setup_op(nor, op, proto);
326 	return spi_nor_spimem_exec_op(nor, op);
327 }
328 
329 /**
330  * spi_nor_write_any_volatile_reg() - write any volatile register to flash
331  * memory.
332  * @nor:        pointer to 'struct spi_nor'
333  * @op:		SPI memory operation. op->data.buf must be DMA-able.
334  * @proto:	SPI protocol to use for the register operation.
335  *
336  * Writing volatile registers are instant according to some manufacturers
337  * (Cypress, Micron) and do not need any status polling.
338  *
339  * Return: zero on success, -errno otherwise
340  */
341 int spi_nor_write_any_volatile_reg(struct spi_nor *nor, struct spi_mem_op *op,
342 				   enum spi_nor_protocol proto)
343 {
344 	int ret;
345 
346 	if (!nor->spimem)
347 		return -EOPNOTSUPP;
348 
349 	ret = spi_nor_write_enable(nor);
350 	if (ret)
351 		return ret;
352 	spi_nor_spimem_setup_op(nor, op, proto);
353 	return spi_nor_spimem_exec_op(nor, op);
354 }
355 
356 /**
357  * spi_nor_write_enable() - Set write enable latch with Write Enable command.
358  * @nor:	pointer to 'struct spi_nor'.
359  *
360  * Return: 0 on success, -errno otherwise.
361  */
362 int spi_nor_write_enable(struct spi_nor *nor)
363 {
364 	int ret;
365 
366 	if (nor->spimem) {
367 		struct spi_mem_op op = SPI_NOR_WREN_OP;
368 
369 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
370 
371 		ret = spi_mem_exec_op(nor->spimem, &op);
372 	} else {
373 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WREN,
374 						       NULL, 0);
375 	}
376 
377 	if (ret)
378 		dev_dbg(nor->dev, "error %d on Write Enable\n", ret);
379 
380 	return ret;
381 }
382 
383 /**
384  * spi_nor_write_disable() - Send Write Disable instruction to the chip.
385  * @nor:	pointer to 'struct spi_nor'.
386  *
387  * Return: 0 on success, -errno otherwise.
388  */
389 int spi_nor_write_disable(struct spi_nor *nor)
390 {
391 	int ret;
392 
393 	if (nor->spimem) {
394 		struct spi_mem_op op = SPI_NOR_WRDI_OP;
395 
396 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
397 
398 		ret = spi_mem_exec_op(nor->spimem, &op);
399 	} else {
400 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRDI,
401 						       NULL, 0);
402 	}
403 
404 	if (ret)
405 		dev_dbg(nor->dev, "error %d on Write Disable\n", ret);
406 
407 	return ret;
408 }
409 
410 /**
411  * spi_nor_read_id() - Read the JEDEC ID.
412  * @nor:	pointer to 'struct spi_nor'.
413  * @naddr:	number of address bytes to send. Can be zero if the operation
414  *		does not need to send an address.
415  * @ndummy:	number of dummy bytes to send after an opcode or address. Can
416  *		be zero if the operation does not require dummy bytes.
417  * @id:		pointer to a DMA-able buffer where the value of the JEDEC ID
418  *		will be written.
419  * @proto:	the SPI protocol for register operation.
420  *
421  * Return: 0 on success, -errno otherwise.
422  */
423 int spi_nor_read_id(struct spi_nor *nor, u8 naddr, u8 ndummy, u8 *id,
424 		    enum spi_nor_protocol proto)
425 {
426 	int ret;
427 
428 	if (nor->spimem) {
429 		struct spi_mem_op op =
430 			SPI_NOR_READID_OP(naddr, ndummy, id, SPI_NOR_MAX_ID_LEN);
431 
432 		spi_nor_spimem_setup_op(nor, &op, proto);
433 		ret = spi_mem_exec_op(nor->spimem, &op);
434 	} else {
435 		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDID, id,
436 						    SPI_NOR_MAX_ID_LEN);
437 	}
438 	return ret;
439 }
440 
441 /**
442  * spi_nor_read_sr() - Read the Status Register.
443  * @nor:	pointer to 'struct spi_nor'.
444  * @sr:		pointer to a DMA-able buffer where the value of the
445  *              Status Register will be written. Should be at least 2 bytes.
446  *
447  * Return: 0 on success, -errno otherwise.
448  */
449 int spi_nor_read_sr(struct spi_nor *nor, u8 *sr)
450 {
451 	int ret;
452 
453 	if (nor->spimem) {
454 		struct spi_mem_op op = SPI_NOR_RDSR_OP(sr);
455 
456 		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
457 			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
458 			op.dummy.nbytes = nor->params->rdsr_dummy;
459 			/*
460 			 * We don't want to read only one byte in DTR mode. So,
461 			 * read 2 and then discard the second byte.
462 			 */
463 			op.data.nbytes = 2;
464 		}
465 
466 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
467 
468 		ret = spi_mem_exec_op(nor->spimem, &op);
469 	} else {
470 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR, sr,
471 						      1);
472 	}
473 
474 	if (ret)
475 		dev_dbg(nor->dev, "error %d reading SR\n", ret);
476 
477 	return ret;
478 }
479 
480 /**
481  * spi_nor_read_cr() - Read the Configuration Register using the
482  * SPINOR_OP_RDCR (35h) command.
483  * @nor:	pointer to 'struct spi_nor'
484  * @cr:		pointer to a DMA-able buffer where the value of the
485  *              Configuration Register will be written.
486  *
487  * Return: 0 on success, -errno otherwise.
488  */
489 int spi_nor_read_cr(struct spi_nor *nor, u8 *cr)
490 {
491 	int ret;
492 
493 	if (nor->spimem) {
494 		struct spi_mem_op op = SPI_NOR_RDCR_OP(cr);
495 
496 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
497 
498 		ret = spi_mem_exec_op(nor->spimem, &op);
499 	} else {
500 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDCR, cr,
501 						      1);
502 	}
503 
504 	if (ret)
505 		dev_dbg(nor->dev, "error %d reading CR\n", ret);
506 
507 	return ret;
508 }
509 
510 /**
511  * spi_nor_set_4byte_addr_mode_en4b_ex4b() - Enter/Exit 4-byte address mode
512  *			using SPINOR_OP_EN4B/SPINOR_OP_EX4B. Typically used by
513  *			Winbond and Macronix.
514  * @nor:	pointer to 'struct spi_nor'.
515  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
516  *		address mode.
517  *
518  * Return: 0 on success, -errno otherwise.
519  */
520 int spi_nor_set_4byte_addr_mode_en4b_ex4b(struct spi_nor *nor, bool enable)
521 {
522 	int ret;
523 
524 	if (nor->spimem) {
525 		struct spi_mem_op op = SPI_NOR_EN4B_EX4B_OP(enable);
526 
527 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
528 
529 		ret = spi_mem_exec_op(nor->spimem, &op);
530 	} else {
531 		ret = spi_nor_controller_ops_write_reg(nor,
532 						       enable ? SPINOR_OP_EN4B :
533 								SPINOR_OP_EX4B,
534 						       NULL, 0);
535 	}
536 
537 	if (ret)
538 		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
539 
540 	return ret;
541 }
542 
543 /**
544  * spi_nor_set_4byte_addr_mode_wren_en4b_ex4b() - Set 4-byte address mode using
545  * SPINOR_OP_WREN followed by SPINOR_OP_EN4B or SPINOR_OP_EX4B. Typically used
546  * by ST and Micron flashes.
547  * @nor:	pointer to 'struct spi_nor'.
548  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
549  *		address mode.
550  *
551  * Return: 0 on success, -errno otherwise.
552  */
553 int spi_nor_set_4byte_addr_mode_wren_en4b_ex4b(struct spi_nor *nor, bool enable)
554 {
555 	int ret;
556 
557 	ret = spi_nor_write_enable(nor);
558 	if (ret)
559 		return ret;
560 
561 	ret = spi_nor_set_4byte_addr_mode_en4b_ex4b(nor, enable);
562 	if (ret)
563 		return ret;
564 
565 	return spi_nor_write_disable(nor);
566 }
567 
568 /**
569  * spi_nor_set_4byte_addr_mode_brwr() - Set 4-byte address mode using
570  *			SPINOR_OP_BRWR. Typically used by Spansion flashes.
571  * @nor:	pointer to 'struct spi_nor'.
572  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
573  *		address mode.
574  *
575  * 8-bit volatile bank register used to define A[30:A24] bits. MSB (bit[7]) is
576  * used to enable/disable 4-byte address mode. When MSB is set to ‘1’, 4-byte
577  * address mode is active and A[30:24] bits are don’t care. Write instruction is
578  * SPINOR_OP_BRWR(17h) with 1 byte of data.
579  *
580  * Return: 0 on success, -errno otherwise.
581  */
582 int spi_nor_set_4byte_addr_mode_brwr(struct spi_nor *nor, bool enable)
583 {
584 	int ret;
585 
586 	nor->bouncebuf[0] = enable << 7;
587 
588 	if (nor->spimem) {
589 		struct spi_mem_op op = SPI_NOR_BRWR_OP(nor->bouncebuf);
590 
591 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
592 
593 		ret = spi_mem_exec_op(nor->spimem, &op);
594 	} else {
595 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_BRWR,
596 						       nor->bouncebuf, 1);
597 	}
598 
599 	if (ret)
600 		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
601 
602 	return ret;
603 }
604 
605 /**
606  * spi_nor_sr_ready() - Query the Status Register to see if the flash is ready
607  * for new commands.
608  * @nor:	pointer to 'struct spi_nor'.
609  *
610  * Return: 1 if ready, 0 if not ready, -errno on errors.
611  */
612 int spi_nor_sr_ready(struct spi_nor *nor)
613 {
614 	int ret;
615 
616 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
617 	if (ret)
618 		return ret;
619 
620 	return !(nor->bouncebuf[0] & SR_WIP);
621 }
622 
623 /**
624  * spi_nor_use_parallel_locking() - Checks if RWW locking scheme shall be used
625  * @nor:	pointer to 'struct spi_nor'.
626  *
627  * Return: true if parallel locking is enabled, false otherwise.
628  */
629 static bool spi_nor_use_parallel_locking(struct spi_nor *nor)
630 {
631 	return nor->flags & SNOR_F_RWW;
632 }
633 
634 /* Locking helpers for status read operations */
635 static int spi_nor_rww_start_rdst(struct spi_nor *nor)
636 {
637 	struct spi_nor_rww *rww = &nor->rww;
638 	int ret = -EAGAIN;
639 
640 	mutex_lock(&nor->lock);
641 
642 	if (rww->ongoing_io || rww->ongoing_rd)
643 		goto busy;
644 
645 	rww->ongoing_io = true;
646 	rww->ongoing_rd = true;
647 	ret = 0;
648 
649 busy:
650 	mutex_unlock(&nor->lock);
651 	return ret;
652 }
653 
654 static void spi_nor_rww_end_rdst(struct spi_nor *nor)
655 {
656 	struct spi_nor_rww *rww = &nor->rww;
657 
658 	mutex_lock(&nor->lock);
659 
660 	rww->ongoing_io = false;
661 	rww->ongoing_rd = false;
662 
663 	mutex_unlock(&nor->lock);
664 }
665 
666 static int spi_nor_lock_rdst(struct spi_nor *nor)
667 {
668 	if (spi_nor_use_parallel_locking(nor))
669 		return spi_nor_rww_start_rdst(nor);
670 
671 	return 0;
672 }
673 
674 static void spi_nor_unlock_rdst(struct spi_nor *nor)
675 {
676 	if (spi_nor_use_parallel_locking(nor)) {
677 		spi_nor_rww_end_rdst(nor);
678 		wake_up(&nor->rww.wait);
679 	}
680 }
681 
682 /**
683  * spi_nor_ready() - Query the flash to see if it is ready for new commands.
684  * @nor:	pointer to 'struct spi_nor'.
685  *
686  * Return: 1 if ready, 0 if not ready, -errno on errors.
687  */
688 static int spi_nor_ready(struct spi_nor *nor)
689 {
690 	int ret;
691 
692 	ret = spi_nor_lock_rdst(nor);
693 	if (ret)
694 		return 0;
695 
696 	/* Flashes might override the standard routine. */
697 	if (nor->params->ready)
698 		ret = nor->params->ready(nor);
699 	else
700 		ret = spi_nor_sr_ready(nor);
701 
702 	spi_nor_unlock_rdst(nor);
703 
704 	return ret;
705 }
706 
707 /**
708  * spi_nor_wait_till_ready_with_timeout() - Service routine to read the
709  * Status Register until ready, or timeout occurs.
710  * @nor:		pointer to "struct spi_nor".
711  * @timeout_jiffies:	jiffies to wait until timeout.
712  *
713  * Return: 0 on success, -errno otherwise.
714  */
715 static int spi_nor_wait_till_ready_with_timeout(struct spi_nor *nor,
716 						unsigned long timeout_jiffies)
717 {
718 	unsigned long deadline;
719 	int timeout = 0, ret;
720 
721 	deadline = jiffies + timeout_jiffies;
722 
723 	while (!timeout) {
724 		if (time_after_eq(jiffies, deadline))
725 			timeout = 1;
726 
727 		ret = spi_nor_ready(nor);
728 		if (ret < 0)
729 			return ret;
730 		if (ret)
731 			return 0;
732 
733 		cond_resched();
734 	}
735 
736 	dev_dbg(nor->dev, "flash operation timed out\n");
737 
738 	return -ETIMEDOUT;
739 }
740 
741 /**
742  * spi_nor_wait_till_ready() - Wait for a predefined amount of time for the
743  * flash to be ready, or timeout occurs.
744  * @nor:	pointer to "struct spi_nor".
745  *
746  * Return: 0 on success, -errno otherwise.
747  */
748 int spi_nor_wait_till_ready(struct spi_nor *nor)
749 {
750 	return spi_nor_wait_till_ready_with_timeout(nor,
751 						    DEFAULT_READY_WAIT_JIFFIES);
752 }
753 
754 /**
755  * spi_nor_global_block_unlock() - Unlock Global Block Protection.
756  * @nor:	pointer to 'struct spi_nor'.
757  *
758  * Return: 0 on success, -errno otherwise.
759  */
760 int spi_nor_global_block_unlock(struct spi_nor *nor)
761 {
762 	int ret;
763 
764 	ret = spi_nor_write_enable(nor);
765 	if (ret)
766 		return ret;
767 
768 	if (nor->spimem) {
769 		struct spi_mem_op op = SPI_NOR_GBULK_OP;
770 
771 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
772 
773 		ret = spi_mem_exec_op(nor->spimem, &op);
774 	} else {
775 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_GBULK,
776 						       NULL, 0);
777 	}
778 
779 	if (ret) {
780 		dev_dbg(nor->dev, "error %d on Global Block Unlock\n", ret);
781 		return ret;
782 	}
783 
784 	return spi_nor_wait_till_ready(nor);
785 }
786 
787 /**
788  * spi_nor_write_sr() - Write the Status Register.
789  * @nor:	pointer to 'struct spi_nor'.
790  * @sr:		pointer to DMA-able buffer to write to the Status Register.
791  * @len:	number of bytes to write to the Status Register.
792  *
793  * Return: 0 on success, -errno otherwise.
794  */
795 int spi_nor_write_sr(struct spi_nor *nor, const u8 *sr, size_t len)
796 {
797 	int ret;
798 
799 	ret = spi_nor_write_enable(nor);
800 	if (ret)
801 		return ret;
802 
803 	if (nor->spimem) {
804 		struct spi_mem_op op = SPI_NOR_WRSR_OP(sr, len);
805 
806 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
807 
808 		ret = spi_mem_exec_op(nor->spimem, &op);
809 	} else {
810 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR, sr,
811 						       len);
812 	}
813 
814 	if (ret) {
815 		dev_dbg(nor->dev, "error %d writing SR\n", ret);
816 		return ret;
817 	}
818 
819 	return spi_nor_wait_till_ready(nor);
820 }
821 
822 /**
823  * spi_nor_write_sr1_and_check() - Write one byte to the Status Register 1 and
824  * ensure that the byte written match the received value.
825  * @nor:	pointer to a 'struct spi_nor'.
826  * @sr1:	byte value to be written to the Status Register.
827  *
828  * Return: 0 on success, -errno otherwise.
829  */
830 static int spi_nor_write_sr1_and_check(struct spi_nor *nor, u8 sr1)
831 {
832 	int ret;
833 
834 	nor->bouncebuf[0] = sr1;
835 
836 	ret = spi_nor_write_sr(nor, nor->bouncebuf, 1);
837 	if (ret)
838 		return ret;
839 
840 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
841 	if (ret)
842 		return ret;
843 
844 	if (nor->bouncebuf[0] != sr1) {
845 		dev_dbg(nor->dev, "SR1: read back test failed\n");
846 		return -EIO;
847 	}
848 
849 	return 0;
850 }
851 
852 /**
853  * spi_nor_write_16bit_sr_and_check() - Write the Status Register 1 and the
854  * Status Register 2 in one shot. Ensure that the byte written in the Status
855  * Register 1 match the received value, and that the 16-bit Write did not
856  * affect what was already in the Status Register 2.
857  * @nor:	pointer to a 'struct spi_nor'.
858  * @sr1:	byte value to be written to the Status Register 1.
859  *
860  * Return: 0 on success, -errno otherwise.
861  */
862 static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1)
863 {
864 	int ret;
865 	u8 *sr_cr = nor->bouncebuf;
866 	u8 cr_written;
867 
868 	/* Make sure we don't overwrite the contents of Status Register 2. */
869 	if (!(nor->flags & SNOR_F_NO_READ_CR)) {
870 		ret = spi_nor_read_cr(nor, &sr_cr[1]);
871 		if (ret)
872 			return ret;
873 	} else if (spi_nor_get_protocol_width(nor->read_proto) == 4 &&
874 		   spi_nor_get_protocol_width(nor->write_proto) == 4 &&
875 		   nor->params->quad_enable) {
876 		/*
877 		 * If the Status Register 2 Read command (35h) is not
878 		 * supported, we should at least be sure we don't
879 		 * change the value of the SR2 Quad Enable bit.
880 		 *
881 		 * When the Quad Enable method is set and the buswidth is 4, we
882 		 * can safely assume that the value of the QE bit is one, as a
883 		 * consequence of the nor->params->quad_enable() call.
884 		 *
885 		 * According to the JESD216 revB standard, BFPT DWORDS[15],
886 		 * bits 22:20, the 16-bit Write Status (01h) command is
887 		 * available just for the cases in which the QE bit is
888 		 * described in SR2 at BIT(1).
889 		 */
890 		sr_cr[1] = SR2_QUAD_EN_BIT1;
891 	} else {
892 		sr_cr[1] = 0;
893 	}
894 
895 	sr_cr[0] = sr1;
896 
897 	ret = spi_nor_write_sr(nor, sr_cr, 2);
898 	if (ret)
899 		return ret;
900 
901 	ret = spi_nor_read_sr(nor, sr_cr);
902 	if (ret)
903 		return ret;
904 
905 	if (sr1 != sr_cr[0]) {
906 		dev_dbg(nor->dev, "SR: Read back test failed\n");
907 		return -EIO;
908 	}
909 
910 	if (nor->flags & SNOR_F_NO_READ_CR)
911 		return 0;
912 
913 	cr_written = sr_cr[1];
914 
915 	ret = spi_nor_read_cr(nor, &sr_cr[1]);
916 	if (ret)
917 		return ret;
918 
919 	if (cr_written != sr_cr[1]) {
920 		dev_dbg(nor->dev, "CR: read back test failed\n");
921 		return -EIO;
922 	}
923 
924 	return 0;
925 }
926 
927 /**
928  * spi_nor_write_16bit_cr_and_check() - Write the Status Register 1 and the
929  * Configuration Register in one shot. Ensure that the byte written in the
930  * Configuration Register match the received value, and that the 16-bit Write
931  * did not affect what was already in the Status Register 1.
932  * @nor:	pointer to a 'struct spi_nor'.
933  * @cr:		byte value to be written to the Configuration Register.
934  *
935  * Return: 0 on success, -errno otherwise.
936  */
937 int spi_nor_write_16bit_cr_and_check(struct spi_nor *nor, u8 cr)
938 {
939 	int ret;
940 	u8 *sr_cr = nor->bouncebuf;
941 	u8 sr_written;
942 
943 	/* Keep the current value of the Status Register 1. */
944 	ret = spi_nor_read_sr(nor, sr_cr);
945 	if (ret)
946 		return ret;
947 
948 	sr_cr[1] = cr;
949 
950 	ret = spi_nor_write_sr(nor, sr_cr, 2);
951 	if (ret)
952 		return ret;
953 
954 	sr_written = sr_cr[0];
955 
956 	ret = spi_nor_read_sr(nor, sr_cr);
957 	if (ret)
958 		return ret;
959 
960 	if (sr_written != sr_cr[0]) {
961 		dev_dbg(nor->dev, "SR: Read back test failed\n");
962 		return -EIO;
963 	}
964 
965 	if (nor->flags & SNOR_F_NO_READ_CR)
966 		return 0;
967 
968 	ret = spi_nor_read_cr(nor, &sr_cr[1]);
969 	if (ret)
970 		return ret;
971 
972 	if (cr != sr_cr[1]) {
973 		dev_dbg(nor->dev, "CR: read back test failed\n");
974 		return -EIO;
975 	}
976 
977 	return 0;
978 }
979 
980 /**
981  * spi_nor_write_sr_and_check() - Write the Status Register 1 and ensure that
982  * the byte written match the received value without affecting other bits in the
983  * Status Register 1 and 2.
984  * @nor:	pointer to a 'struct spi_nor'.
985  * @sr1:	byte value to be written to the Status Register.
986  *
987  * Return: 0 on success, -errno otherwise.
988  */
989 int spi_nor_write_sr_and_check(struct spi_nor *nor, u8 sr1)
990 {
991 	if (nor->flags & SNOR_F_HAS_16BIT_SR)
992 		return spi_nor_write_16bit_sr_and_check(nor, sr1);
993 
994 	return spi_nor_write_sr1_and_check(nor, sr1);
995 }
996 
997 /**
998  * spi_nor_write_sr2() - Write the Status Register 2 using the
999  * SPINOR_OP_WRSR2 (3eh) command.
1000  * @nor:	pointer to 'struct spi_nor'.
1001  * @sr2:	pointer to DMA-able buffer to write to the Status Register 2.
1002  *
1003  * Return: 0 on success, -errno otherwise.
1004  */
1005 static int spi_nor_write_sr2(struct spi_nor *nor, const u8 *sr2)
1006 {
1007 	int ret;
1008 
1009 	ret = spi_nor_write_enable(nor);
1010 	if (ret)
1011 		return ret;
1012 
1013 	if (nor->spimem) {
1014 		struct spi_mem_op op = SPI_NOR_WRSR2_OP(sr2);
1015 
1016 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1017 
1018 		ret = spi_mem_exec_op(nor->spimem, &op);
1019 	} else {
1020 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR2,
1021 						       sr2, 1);
1022 	}
1023 
1024 	if (ret) {
1025 		dev_dbg(nor->dev, "error %d writing SR2\n", ret);
1026 		return ret;
1027 	}
1028 
1029 	return spi_nor_wait_till_ready(nor);
1030 }
1031 
1032 /**
1033  * spi_nor_read_sr2() - Read the Status Register 2 using the
1034  * SPINOR_OP_RDSR2 (3fh) command.
1035  * @nor:	pointer to 'struct spi_nor'.
1036  * @sr2:	pointer to DMA-able buffer where the value of the
1037  *		Status Register 2 will be written.
1038  *
1039  * Return: 0 on success, -errno otherwise.
1040  */
1041 static int spi_nor_read_sr2(struct spi_nor *nor, u8 *sr2)
1042 {
1043 	int ret;
1044 
1045 	if (nor->spimem) {
1046 		struct spi_mem_op op = SPI_NOR_RDSR2_OP(sr2);
1047 
1048 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1049 
1050 		ret = spi_mem_exec_op(nor->spimem, &op);
1051 	} else {
1052 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR2, sr2,
1053 						      1);
1054 	}
1055 
1056 	if (ret)
1057 		dev_dbg(nor->dev, "error %d reading SR2\n", ret);
1058 
1059 	return ret;
1060 }
1061 
1062 /**
1063  * spi_nor_erase_chip() - Erase the entire flash memory.
1064  * @nor:	pointer to 'struct spi_nor'.
1065  *
1066  * Return: 0 on success, -errno otherwise.
1067  */
1068 static int spi_nor_erase_chip(struct spi_nor *nor)
1069 {
1070 	int ret;
1071 
1072 	dev_dbg(nor->dev, " %lldKiB\n", (long long)(nor->mtd.size >> 10));
1073 
1074 	if (nor->spimem) {
1075 		struct spi_mem_op op = SPI_NOR_CHIP_ERASE_OP;
1076 
1077 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1078 
1079 		ret = spi_mem_exec_op(nor->spimem, &op);
1080 	} else {
1081 		ret = spi_nor_controller_ops_write_reg(nor,
1082 						       SPINOR_OP_CHIP_ERASE,
1083 						       NULL, 0);
1084 	}
1085 
1086 	if (ret)
1087 		dev_dbg(nor->dev, "error %d erasing chip\n", ret);
1088 
1089 	return ret;
1090 }
1091 
1092 static u8 spi_nor_convert_opcode(u8 opcode, const u8 table[][2], size_t size)
1093 {
1094 	size_t i;
1095 
1096 	for (i = 0; i < size; i++)
1097 		if (table[i][0] == opcode)
1098 			return table[i][1];
1099 
1100 	/* No conversion found, keep input op code. */
1101 	return opcode;
1102 }
1103 
1104 u8 spi_nor_convert_3to4_read(u8 opcode)
1105 {
1106 	static const u8 spi_nor_3to4_read[][2] = {
1107 		{ SPINOR_OP_READ,	SPINOR_OP_READ_4B },
1108 		{ SPINOR_OP_READ_FAST,	SPINOR_OP_READ_FAST_4B },
1109 		{ SPINOR_OP_READ_1_1_2,	SPINOR_OP_READ_1_1_2_4B },
1110 		{ SPINOR_OP_READ_1_2_2,	SPINOR_OP_READ_1_2_2_4B },
1111 		{ SPINOR_OP_READ_1_1_4,	SPINOR_OP_READ_1_1_4_4B },
1112 		{ SPINOR_OP_READ_1_4_4,	SPINOR_OP_READ_1_4_4_4B },
1113 		{ SPINOR_OP_READ_1_1_8,	SPINOR_OP_READ_1_1_8_4B },
1114 		{ SPINOR_OP_READ_1_8_8,	SPINOR_OP_READ_1_8_8_4B },
1115 
1116 		{ SPINOR_OP_READ_1_1_1_DTR,	SPINOR_OP_READ_1_1_1_DTR_4B },
1117 		{ SPINOR_OP_READ_1_2_2_DTR,	SPINOR_OP_READ_1_2_2_DTR_4B },
1118 		{ SPINOR_OP_READ_1_4_4_DTR,	SPINOR_OP_READ_1_4_4_DTR_4B },
1119 	};
1120 
1121 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_read,
1122 				      ARRAY_SIZE(spi_nor_3to4_read));
1123 }
1124 
1125 static u8 spi_nor_convert_3to4_program(u8 opcode)
1126 {
1127 	static const u8 spi_nor_3to4_program[][2] = {
1128 		{ SPINOR_OP_PP,		SPINOR_OP_PP_4B },
1129 		{ SPINOR_OP_PP_1_1_4,	SPINOR_OP_PP_1_1_4_4B },
1130 		{ SPINOR_OP_PP_1_4_4,	SPINOR_OP_PP_1_4_4_4B },
1131 		{ SPINOR_OP_PP_1_1_8,	SPINOR_OP_PP_1_1_8_4B },
1132 		{ SPINOR_OP_PP_1_8_8,	SPINOR_OP_PP_1_8_8_4B },
1133 	};
1134 
1135 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_program,
1136 				      ARRAY_SIZE(spi_nor_3to4_program));
1137 }
1138 
1139 static u8 spi_nor_convert_3to4_erase(u8 opcode)
1140 {
1141 	static const u8 spi_nor_3to4_erase[][2] = {
1142 		{ SPINOR_OP_BE_4K,	SPINOR_OP_BE_4K_4B },
1143 		{ SPINOR_OP_BE_32K,	SPINOR_OP_BE_32K_4B },
1144 		{ SPINOR_OP_SE,		SPINOR_OP_SE_4B },
1145 	};
1146 
1147 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_erase,
1148 				      ARRAY_SIZE(spi_nor_3to4_erase));
1149 }
1150 
1151 static bool spi_nor_has_uniform_erase(const struct spi_nor *nor)
1152 {
1153 	return !!nor->params->erase_map.uniform_erase_type;
1154 }
1155 
1156 static void spi_nor_set_4byte_opcodes(struct spi_nor *nor)
1157 {
1158 	nor->read_opcode = spi_nor_convert_3to4_read(nor->read_opcode);
1159 	nor->program_opcode = spi_nor_convert_3to4_program(nor->program_opcode);
1160 	nor->erase_opcode = spi_nor_convert_3to4_erase(nor->erase_opcode);
1161 
1162 	if (!spi_nor_has_uniform_erase(nor)) {
1163 		struct spi_nor_erase_map *map = &nor->params->erase_map;
1164 		struct spi_nor_erase_type *erase;
1165 		int i;
1166 
1167 		for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
1168 			erase = &map->erase_type[i];
1169 			erase->opcode =
1170 				spi_nor_convert_3to4_erase(erase->opcode);
1171 		}
1172 	}
1173 }
1174 
1175 static int spi_nor_prep(struct spi_nor *nor)
1176 {
1177 	int ret = 0;
1178 
1179 	if (nor->controller_ops && nor->controller_ops->prepare)
1180 		ret = nor->controller_ops->prepare(nor);
1181 
1182 	return ret;
1183 }
1184 
1185 static void spi_nor_unprep(struct spi_nor *nor)
1186 {
1187 	if (nor->controller_ops && nor->controller_ops->unprepare)
1188 		nor->controller_ops->unprepare(nor);
1189 }
1190 
1191 static void spi_nor_offset_to_banks(u64 bank_size, loff_t start, size_t len,
1192 				    u8 *first, u8 *last)
1193 {
1194 	/* This is currently safe, the number of banks being very small */
1195 	*first = DIV_ROUND_DOWN_ULL(start, bank_size);
1196 	*last = DIV_ROUND_DOWN_ULL(start + len - 1, bank_size);
1197 }
1198 
1199 /* Generic helpers for internal locking and serialization */
1200 static bool spi_nor_rww_start_io(struct spi_nor *nor)
1201 {
1202 	struct spi_nor_rww *rww = &nor->rww;
1203 	bool start = false;
1204 
1205 	mutex_lock(&nor->lock);
1206 
1207 	if (rww->ongoing_io)
1208 		goto busy;
1209 
1210 	rww->ongoing_io = true;
1211 	start = true;
1212 
1213 busy:
1214 	mutex_unlock(&nor->lock);
1215 	return start;
1216 }
1217 
1218 static void spi_nor_rww_end_io(struct spi_nor *nor)
1219 {
1220 	mutex_lock(&nor->lock);
1221 	nor->rww.ongoing_io = false;
1222 	mutex_unlock(&nor->lock);
1223 }
1224 
1225 static int spi_nor_lock_device(struct spi_nor *nor)
1226 {
1227 	if (!spi_nor_use_parallel_locking(nor))
1228 		return 0;
1229 
1230 	return wait_event_killable(nor->rww.wait, spi_nor_rww_start_io(nor));
1231 }
1232 
1233 static void spi_nor_unlock_device(struct spi_nor *nor)
1234 {
1235 	if (spi_nor_use_parallel_locking(nor)) {
1236 		spi_nor_rww_end_io(nor);
1237 		wake_up(&nor->rww.wait);
1238 	}
1239 }
1240 
1241 /* Generic helpers for internal locking and serialization */
1242 static bool spi_nor_rww_start_exclusive(struct spi_nor *nor)
1243 {
1244 	struct spi_nor_rww *rww = &nor->rww;
1245 	bool start = false;
1246 
1247 	mutex_lock(&nor->lock);
1248 
1249 	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
1250 		goto busy;
1251 
1252 	rww->ongoing_io = true;
1253 	rww->ongoing_rd = true;
1254 	rww->ongoing_pe = true;
1255 	start = true;
1256 
1257 busy:
1258 	mutex_unlock(&nor->lock);
1259 	return start;
1260 }
1261 
1262 static void spi_nor_rww_end_exclusive(struct spi_nor *nor)
1263 {
1264 	struct spi_nor_rww *rww = &nor->rww;
1265 
1266 	mutex_lock(&nor->lock);
1267 	rww->ongoing_io = false;
1268 	rww->ongoing_rd = false;
1269 	rww->ongoing_pe = false;
1270 	mutex_unlock(&nor->lock);
1271 }
1272 
1273 int spi_nor_prep_and_lock(struct spi_nor *nor)
1274 {
1275 	int ret;
1276 
1277 	ret = spi_nor_prep(nor);
1278 	if (ret)
1279 		return ret;
1280 
1281 	if (!spi_nor_use_parallel_locking(nor))
1282 		mutex_lock(&nor->lock);
1283 	else
1284 		ret = wait_event_killable(nor->rww.wait,
1285 					  spi_nor_rww_start_exclusive(nor));
1286 
1287 	return ret;
1288 }
1289 
1290 void spi_nor_unlock_and_unprep(struct spi_nor *nor)
1291 {
1292 	if (!spi_nor_use_parallel_locking(nor)) {
1293 		mutex_unlock(&nor->lock);
1294 	} else {
1295 		spi_nor_rww_end_exclusive(nor);
1296 		wake_up(&nor->rww.wait);
1297 	}
1298 
1299 	spi_nor_unprep(nor);
1300 }
1301 
1302 /* Internal locking helpers for program and erase operations */
1303 static bool spi_nor_rww_start_pe(struct spi_nor *nor, loff_t start, size_t len)
1304 {
1305 	struct spi_nor_rww *rww = &nor->rww;
1306 	unsigned int used_banks = 0;
1307 	bool started = false;
1308 	u8 first, last;
1309 	int bank;
1310 
1311 	mutex_lock(&nor->lock);
1312 
1313 	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
1314 		goto busy;
1315 
1316 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1317 	for (bank = first; bank <= last; bank++) {
1318 		if (rww->used_banks & BIT(bank))
1319 			goto busy;
1320 
1321 		used_banks |= BIT(bank);
1322 	}
1323 
1324 	rww->used_banks |= used_banks;
1325 	rww->ongoing_pe = true;
1326 	started = true;
1327 
1328 busy:
1329 	mutex_unlock(&nor->lock);
1330 	return started;
1331 }
1332 
1333 static void spi_nor_rww_end_pe(struct spi_nor *nor, loff_t start, size_t len)
1334 {
1335 	struct spi_nor_rww *rww = &nor->rww;
1336 	u8 first, last;
1337 	int bank;
1338 
1339 	mutex_lock(&nor->lock);
1340 
1341 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1342 	for (bank = first; bank <= last; bank++)
1343 		rww->used_banks &= ~BIT(bank);
1344 
1345 	rww->ongoing_pe = false;
1346 
1347 	mutex_unlock(&nor->lock);
1348 }
1349 
1350 static int spi_nor_prep_and_lock_pe(struct spi_nor *nor, loff_t start, size_t len)
1351 {
1352 	int ret;
1353 
1354 	ret = spi_nor_prep(nor);
1355 	if (ret)
1356 		return ret;
1357 
1358 	if (!spi_nor_use_parallel_locking(nor))
1359 		mutex_lock(&nor->lock);
1360 	else
1361 		ret = wait_event_killable(nor->rww.wait,
1362 					  spi_nor_rww_start_pe(nor, start, len));
1363 
1364 	return ret;
1365 }
1366 
1367 static void spi_nor_unlock_and_unprep_pe(struct spi_nor *nor, loff_t start, size_t len)
1368 {
1369 	if (!spi_nor_use_parallel_locking(nor)) {
1370 		mutex_unlock(&nor->lock);
1371 	} else {
1372 		spi_nor_rww_end_pe(nor, start, len);
1373 		wake_up(&nor->rww.wait);
1374 	}
1375 
1376 	spi_nor_unprep(nor);
1377 }
1378 
1379 /* Internal locking helpers for read operations */
1380 static bool spi_nor_rww_start_rd(struct spi_nor *nor, loff_t start, size_t len)
1381 {
1382 	struct spi_nor_rww *rww = &nor->rww;
1383 	unsigned int used_banks = 0;
1384 	bool started = false;
1385 	u8 first, last;
1386 	int bank;
1387 
1388 	mutex_lock(&nor->lock);
1389 
1390 	if (rww->ongoing_io || rww->ongoing_rd)
1391 		goto busy;
1392 
1393 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1394 	for (bank = first; bank <= last; bank++) {
1395 		if (rww->used_banks & BIT(bank))
1396 			goto busy;
1397 
1398 		used_banks |= BIT(bank);
1399 	}
1400 
1401 	rww->used_banks |= used_banks;
1402 	rww->ongoing_io = true;
1403 	rww->ongoing_rd = true;
1404 	started = true;
1405 
1406 busy:
1407 	mutex_unlock(&nor->lock);
1408 	return started;
1409 }
1410 
1411 static void spi_nor_rww_end_rd(struct spi_nor *nor, loff_t start, size_t len)
1412 {
1413 	struct spi_nor_rww *rww = &nor->rww;
1414 	u8 first, last;
1415 	int bank;
1416 
1417 	mutex_lock(&nor->lock);
1418 
1419 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1420 	for (bank = first; bank <= last; bank++)
1421 		nor->rww.used_banks &= ~BIT(bank);
1422 
1423 	rww->ongoing_io = false;
1424 	rww->ongoing_rd = false;
1425 
1426 	mutex_unlock(&nor->lock);
1427 }
1428 
1429 static int spi_nor_prep_and_lock_rd(struct spi_nor *nor, loff_t start, size_t len)
1430 {
1431 	int ret;
1432 
1433 	ret = spi_nor_prep(nor);
1434 	if (ret)
1435 		return ret;
1436 
1437 	if (!spi_nor_use_parallel_locking(nor))
1438 		mutex_lock(&nor->lock);
1439 	else
1440 		ret = wait_event_killable(nor->rww.wait,
1441 					  spi_nor_rww_start_rd(nor, start, len));
1442 
1443 	return ret;
1444 }
1445 
1446 static void spi_nor_unlock_and_unprep_rd(struct spi_nor *nor, loff_t start, size_t len)
1447 {
1448 	if (!spi_nor_use_parallel_locking(nor)) {
1449 		mutex_unlock(&nor->lock);
1450 	} else {
1451 		spi_nor_rww_end_rd(nor, start, len);
1452 		wake_up(&nor->rww.wait);
1453 	}
1454 
1455 	spi_nor_unprep(nor);
1456 }
1457 
1458 static u32 spi_nor_convert_addr(struct spi_nor *nor, loff_t addr)
1459 {
1460 	if (!nor->params->convert_addr)
1461 		return addr;
1462 
1463 	return nor->params->convert_addr(nor, addr);
1464 }
1465 
1466 /*
1467  * Initiate the erasure of a single sector
1468  */
1469 int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
1470 {
1471 	int i;
1472 
1473 	addr = spi_nor_convert_addr(nor, addr);
1474 
1475 	if (nor->spimem) {
1476 		struct spi_mem_op op =
1477 			SPI_NOR_SECTOR_ERASE_OP(nor->erase_opcode,
1478 						nor->addr_nbytes, addr);
1479 
1480 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1481 
1482 		return spi_mem_exec_op(nor->spimem, &op);
1483 	} else if (nor->controller_ops->erase) {
1484 		return spi_nor_controller_ops_erase(nor, addr);
1485 	}
1486 
1487 	/*
1488 	 * Default implementation, if driver doesn't have a specialized HW
1489 	 * control
1490 	 */
1491 	for (i = nor->addr_nbytes - 1; i >= 0; i--) {
1492 		nor->bouncebuf[i] = addr & 0xff;
1493 		addr >>= 8;
1494 	}
1495 
1496 	return spi_nor_controller_ops_write_reg(nor, nor->erase_opcode,
1497 						nor->bouncebuf, nor->addr_nbytes);
1498 }
1499 
1500 /**
1501  * spi_nor_div_by_erase_size() - calculate remainder and update new dividend
1502  * @erase:	pointer to a structure that describes a SPI NOR erase type
1503  * @dividend:	dividend value
1504  * @remainder:	pointer to u32 remainder (will be updated)
1505  *
1506  * Return: the result of the division
1507  */
1508 static u64 spi_nor_div_by_erase_size(const struct spi_nor_erase_type *erase,
1509 				     u64 dividend, u32 *remainder)
1510 {
1511 	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
1512 	*remainder = (u32)dividend & erase->size_mask;
1513 	return dividend >> erase->size_shift;
1514 }
1515 
1516 /**
1517  * spi_nor_find_best_erase_type() - find the best erase type for the given
1518  *				    offset in the serial flash memory and the
1519  *				    number of bytes to erase. The region in
1520  *				    which the address fits is expected to be
1521  *				    provided.
1522  * @map:	the erase map of the SPI NOR
1523  * @region:	pointer to a structure that describes a SPI NOR erase region
1524  * @addr:	offset in the serial flash memory
1525  * @len:	number of bytes to erase
1526  *
1527  * Return: a pointer to the best fitted erase type, NULL otherwise.
1528  */
1529 static const struct spi_nor_erase_type *
1530 spi_nor_find_best_erase_type(const struct spi_nor_erase_map *map,
1531 			     const struct spi_nor_erase_region *region,
1532 			     u64 addr, u32 len)
1533 {
1534 	const struct spi_nor_erase_type *erase;
1535 	u32 rem;
1536 	int i;
1537 	u8 erase_mask = region->offset & SNOR_ERASE_TYPE_MASK;
1538 
1539 	/*
1540 	 * Erase types are ordered by size, with the smallest erase type at
1541 	 * index 0.
1542 	 */
1543 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
1544 		/* Does the erase region support the tested erase type? */
1545 		if (!(erase_mask & BIT(i)))
1546 			continue;
1547 
1548 		erase = &map->erase_type[i];
1549 		if (!erase->size)
1550 			continue;
1551 
1552 		/* Alignment is not mandatory for overlaid regions */
1553 		if (region->offset & SNOR_OVERLAID_REGION &&
1554 		    region->size <= len)
1555 			return erase;
1556 
1557 		/* Don't erase more than what the user has asked for. */
1558 		if (erase->size > len)
1559 			continue;
1560 
1561 		spi_nor_div_by_erase_size(erase, addr, &rem);
1562 		if (!rem)
1563 			return erase;
1564 	}
1565 
1566 	return NULL;
1567 }
1568 
1569 static u64 spi_nor_region_is_last(const struct spi_nor_erase_region *region)
1570 {
1571 	return region->offset & SNOR_LAST_REGION;
1572 }
1573 
1574 static u64 spi_nor_region_end(const struct spi_nor_erase_region *region)
1575 {
1576 	return (region->offset & ~SNOR_ERASE_FLAGS_MASK) + region->size;
1577 }
1578 
1579 /**
1580  * spi_nor_region_next() - get the next spi nor region
1581  * @region:	pointer to a structure that describes a SPI NOR erase region
1582  *
1583  * Return: the next spi nor region or NULL if last region.
1584  */
1585 struct spi_nor_erase_region *
1586 spi_nor_region_next(struct spi_nor_erase_region *region)
1587 {
1588 	if (spi_nor_region_is_last(region))
1589 		return NULL;
1590 	region++;
1591 	return region;
1592 }
1593 
1594 /**
1595  * spi_nor_find_erase_region() - find the region of the serial flash memory in
1596  *				 which the offset fits
1597  * @map:	the erase map of the SPI NOR
1598  * @addr:	offset in the serial flash memory
1599  *
1600  * Return: a pointer to the spi_nor_erase_region struct, ERR_PTR(-errno)
1601  *	   otherwise.
1602  */
1603 static struct spi_nor_erase_region *
1604 spi_nor_find_erase_region(const struct spi_nor_erase_map *map, u64 addr)
1605 {
1606 	struct spi_nor_erase_region *region = map->regions;
1607 	u64 region_start = region->offset & ~SNOR_ERASE_FLAGS_MASK;
1608 	u64 region_end = region_start + region->size;
1609 
1610 	while (addr < region_start || addr >= region_end) {
1611 		region = spi_nor_region_next(region);
1612 		if (!region)
1613 			return ERR_PTR(-EINVAL);
1614 
1615 		region_start = region->offset & ~SNOR_ERASE_FLAGS_MASK;
1616 		region_end = region_start + region->size;
1617 	}
1618 
1619 	return region;
1620 }
1621 
1622 /**
1623  * spi_nor_init_erase_cmd() - initialize an erase command
1624  * @region:	pointer to a structure that describes a SPI NOR erase region
1625  * @erase:	pointer to a structure that describes a SPI NOR erase type
1626  *
1627  * Return: the pointer to the allocated erase command, ERR_PTR(-errno)
1628  *	   otherwise.
1629  */
1630 static struct spi_nor_erase_command *
1631 spi_nor_init_erase_cmd(const struct spi_nor_erase_region *region,
1632 		       const struct spi_nor_erase_type *erase)
1633 {
1634 	struct spi_nor_erase_command *cmd;
1635 
1636 	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
1637 	if (!cmd)
1638 		return ERR_PTR(-ENOMEM);
1639 
1640 	INIT_LIST_HEAD(&cmd->list);
1641 	cmd->opcode = erase->opcode;
1642 	cmd->count = 1;
1643 
1644 	if (region->offset & SNOR_OVERLAID_REGION)
1645 		cmd->size = region->size;
1646 	else
1647 		cmd->size = erase->size;
1648 
1649 	return cmd;
1650 }
1651 
1652 /**
1653  * spi_nor_destroy_erase_cmd_list() - destroy erase command list
1654  * @erase_list:	list of erase commands
1655  */
1656 static void spi_nor_destroy_erase_cmd_list(struct list_head *erase_list)
1657 {
1658 	struct spi_nor_erase_command *cmd, *next;
1659 
1660 	list_for_each_entry_safe(cmd, next, erase_list, list) {
1661 		list_del(&cmd->list);
1662 		kfree(cmd);
1663 	}
1664 }
1665 
1666 /**
1667  * spi_nor_init_erase_cmd_list() - initialize erase command list
1668  * @nor:	pointer to a 'struct spi_nor'
1669  * @erase_list:	list of erase commands to be executed once we validate that the
1670  *		erase can be performed
1671  * @addr:	offset in the serial flash memory
1672  * @len:	number of bytes to erase
1673  *
1674  * Builds the list of best fitted erase commands and verifies if the erase can
1675  * be performed.
1676  *
1677  * Return: 0 on success, -errno otherwise.
1678  */
1679 static int spi_nor_init_erase_cmd_list(struct spi_nor *nor,
1680 				       struct list_head *erase_list,
1681 				       u64 addr, u32 len)
1682 {
1683 	const struct spi_nor_erase_map *map = &nor->params->erase_map;
1684 	const struct spi_nor_erase_type *erase, *prev_erase = NULL;
1685 	struct spi_nor_erase_region *region;
1686 	struct spi_nor_erase_command *cmd = NULL;
1687 	u64 region_end;
1688 	int ret = -EINVAL;
1689 
1690 	region = spi_nor_find_erase_region(map, addr);
1691 	if (IS_ERR(region))
1692 		return PTR_ERR(region);
1693 
1694 	region_end = spi_nor_region_end(region);
1695 
1696 	while (len) {
1697 		erase = spi_nor_find_best_erase_type(map, region, addr, len);
1698 		if (!erase)
1699 			goto destroy_erase_cmd_list;
1700 
1701 		if (prev_erase != erase ||
1702 		    erase->size != cmd->size ||
1703 		    region->offset & SNOR_OVERLAID_REGION) {
1704 			cmd = spi_nor_init_erase_cmd(region, erase);
1705 			if (IS_ERR(cmd)) {
1706 				ret = PTR_ERR(cmd);
1707 				goto destroy_erase_cmd_list;
1708 			}
1709 
1710 			list_add_tail(&cmd->list, erase_list);
1711 		} else {
1712 			cmd->count++;
1713 		}
1714 
1715 		addr += cmd->size;
1716 		len -= cmd->size;
1717 
1718 		if (len && addr >= region_end) {
1719 			region = spi_nor_region_next(region);
1720 			if (!region)
1721 				goto destroy_erase_cmd_list;
1722 			region_end = spi_nor_region_end(region);
1723 		}
1724 
1725 		prev_erase = erase;
1726 	}
1727 
1728 	return 0;
1729 
1730 destroy_erase_cmd_list:
1731 	spi_nor_destroy_erase_cmd_list(erase_list);
1732 	return ret;
1733 }
1734 
1735 /**
1736  * spi_nor_erase_multi_sectors() - perform a non-uniform erase
1737  * @nor:	pointer to a 'struct spi_nor'
1738  * @addr:	offset in the serial flash memory
1739  * @len:	number of bytes to erase
1740  *
1741  * Build a list of best fitted erase commands and execute it once we validate
1742  * that the erase can be performed.
1743  *
1744  * Return: 0 on success, -errno otherwise.
1745  */
1746 static int spi_nor_erase_multi_sectors(struct spi_nor *nor, u64 addr, u32 len)
1747 {
1748 	LIST_HEAD(erase_list);
1749 	struct spi_nor_erase_command *cmd, *next;
1750 	int ret;
1751 
1752 	ret = spi_nor_init_erase_cmd_list(nor, &erase_list, addr, len);
1753 	if (ret)
1754 		return ret;
1755 
1756 	list_for_each_entry_safe(cmd, next, &erase_list, list) {
1757 		nor->erase_opcode = cmd->opcode;
1758 		while (cmd->count) {
1759 			dev_vdbg(nor->dev, "erase_cmd->size = 0x%08x, erase_cmd->opcode = 0x%02x, erase_cmd->count = %u\n",
1760 				 cmd->size, cmd->opcode, cmd->count);
1761 
1762 			ret = spi_nor_lock_device(nor);
1763 			if (ret)
1764 				goto destroy_erase_cmd_list;
1765 
1766 			ret = spi_nor_write_enable(nor);
1767 			if (ret) {
1768 				spi_nor_unlock_device(nor);
1769 				goto destroy_erase_cmd_list;
1770 			}
1771 
1772 			ret = spi_nor_erase_sector(nor, addr);
1773 			spi_nor_unlock_device(nor);
1774 			if (ret)
1775 				goto destroy_erase_cmd_list;
1776 
1777 			ret = spi_nor_wait_till_ready(nor);
1778 			if (ret)
1779 				goto destroy_erase_cmd_list;
1780 
1781 			addr += cmd->size;
1782 			cmd->count--;
1783 		}
1784 		list_del(&cmd->list);
1785 		kfree(cmd);
1786 	}
1787 
1788 	return 0;
1789 
1790 destroy_erase_cmd_list:
1791 	spi_nor_destroy_erase_cmd_list(&erase_list);
1792 	return ret;
1793 }
1794 
1795 /*
1796  * Erase an address range on the nor chip.  The address range may extend
1797  * one or more erase sectors. Return an error if there is a problem erasing.
1798  */
1799 static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
1800 {
1801 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
1802 	u32 addr, len, rem;
1803 	int ret;
1804 
1805 	dev_dbg(nor->dev, "at 0x%llx, len %lld\n", (long long)instr->addr,
1806 			(long long)instr->len);
1807 
1808 	if (spi_nor_has_uniform_erase(nor)) {
1809 		div_u64_rem(instr->len, mtd->erasesize, &rem);
1810 		if (rem)
1811 			return -EINVAL;
1812 	}
1813 
1814 	addr = instr->addr;
1815 	len = instr->len;
1816 
1817 	ret = spi_nor_prep_and_lock_pe(nor, instr->addr, instr->len);
1818 	if (ret)
1819 		return ret;
1820 
1821 	/* whole-chip erase? */
1822 	if (len == mtd->size && !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) {
1823 		unsigned long timeout;
1824 
1825 		ret = spi_nor_lock_device(nor);
1826 		if (ret)
1827 			goto erase_err;
1828 
1829 		ret = spi_nor_write_enable(nor);
1830 		if (ret) {
1831 			spi_nor_unlock_device(nor);
1832 			goto erase_err;
1833 		}
1834 
1835 		ret = spi_nor_erase_chip(nor);
1836 		spi_nor_unlock_device(nor);
1837 		if (ret)
1838 			goto erase_err;
1839 
1840 		/*
1841 		 * Scale the timeout linearly with the size of the flash, with
1842 		 * a minimum calibrated to an old 2MB flash. We could try to
1843 		 * pull these from CFI/SFDP, but these values should be good
1844 		 * enough for now.
1845 		 */
1846 		timeout = max(CHIP_ERASE_2MB_READY_WAIT_JIFFIES,
1847 			      CHIP_ERASE_2MB_READY_WAIT_JIFFIES *
1848 			      (unsigned long)(mtd->size / SZ_2M));
1849 		ret = spi_nor_wait_till_ready_with_timeout(nor, timeout);
1850 		if (ret)
1851 			goto erase_err;
1852 
1853 	/* REVISIT in some cases we could speed up erasing large regions
1854 	 * by using SPINOR_OP_SE instead of SPINOR_OP_BE_4K.  We may have set up
1855 	 * to use "small sector erase", but that's not always optimal.
1856 	 */
1857 
1858 	/* "sector"-at-a-time erase */
1859 	} else if (spi_nor_has_uniform_erase(nor)) {
1860 		while (len) {
1861 			ret = spi_nor_lock_device(nor);
1862 			if (ret)
1863 				goto erase_err;
1864 
1865 			ret = spi_nor_write_enable(nor);
1866 			if (ret) {
1867 				spi_nor_unlock_device(nor);
1868 				goto erase_err;
1869 			}
1870 
1871 			ret = spi_nor_erase_sector(nor, addr);
1872 			spi_nor_unlock_device(nor);
1873 			if (ret)
1874 				goto erase_err;
1875 
1876 			ret = spi_nor_wait_till_ready(nor);
1877 			if (ret)
1878 				goto erase_err;
1879 
1880 			addr += mtd->erasesize;
1881 			len -= mtd->erasesize;
1882 		}
1883 
1884 	/* erase multiple sectors */
1885 	} else {
1886 		ret = spi_nor_erase_multi_sectors(nor, addr, len);
1887 		if (ret)
1888 			goto erase_err;
1889 	}
1890 
1891 	ret = spi_nor_write_disable(nor);
1892 
1893 erase_err:
1894 	spi_nor_unlock_and_unprep_pe(nor, instr->addr, instr->len);
1895 
1896 	return ret;
1897 }
1898 
1899 /**
1900  * spi_nor_sr1_bit6_quad_enable() - Set the Quad Enable BIT(6) in the Status
1901  * Register 1.
1902  * @nor:	pointer to a 'struct spi_nor'
1903  *
1904  * Bit 6 of the Status Register 1 is the QE bit for Macronix like QSPI memories.
1905  *
1906  * Return: 0 on success, -errno otherwise.
1907  */
1908 int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor)
1909 {
1910 	int ret;
1911 
1912 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
1913 	if (ret)
1914 		return ret;
1915 
1916 	if (nor->bouncebuf[0] & SR1_QUAD_EN_BIT6)
1917 		return 0;
1918 
1919 	nor->bouncebuf[0] |= SR1_QUAD_EN_BIT6;
1920 
1921 	return spi_nor_write_sr1_and_check(nor, nor->bouncebuf[0]);
1922 }
1923 
1924 /**
1925  * spi_nor_sr2_bit1_quad_enable() - set the Quad Enable BIT(1) in the Status
1926  * Register 2.
1927  * @nor:       pointer to a 'struct spi_nor'.
1928  *
1929  * Bit 1 of the Status Register 2 is the QE bit for Spansion like QSPI memories.
1930  *
1931  * Return: 0 on success, -errno otherwise.
1932  */
1933 int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor)
1934 {
1935 	int ret;
1936 
1937 	if (nor->flags & SNOR_F_NO_READ_CR)
1938 		return spi_nor_write_16bit_cr_and_check(nor, SR2_QUAD_EN_BIT1);
1939 
1940 	ret = spi_nor_read_cr(nor, nor->bouncebuf);
1941 	if (ret)
1942 		return ret;
1943 
1944 	if (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)
1945 		return 0;
1946 
1947 	nor->bouncebuf[0] |= SR2_QUAD_EN_BIT1;
1948 
1949 	return spi_nor_write_16bit_cr_and_check(nor, nor->bouncebuf[0]);
1950 }
1951 
1952 /**
1953  * spi_nor_sr2_bit7_quad_enable() - set QE bit in Status Register 2.
1954  * @nor:	pointer to a 'struct spi_nor'
1955  *
1956  * Set the Quad Enable (QE) bit in the Status Register 2.
1957  *
1958  * This is one of the procedures to set the QE bit described in the SFDP
1959  * (JESD216 rev B) specification but no manufacturer using this procedure has
1960  * been identified yet, hence the name of the function.
1961  *
1962  * Return: 0 on success, -errno otherwise.
1963  */
1964 int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor)
1965 {
1966 	u8 *sr2 = nor->bouncebuf;
1967 	int ret;
1968 	u8 sr2_written;
1969 
1970 	/* Check current Quad Enable bit value. */
1971 	ret = spi_nor_read_sr2(nor, sr2);
1972 	if (ret)
1973 		return ret;
1974 	if (*sr2 & SR2_QUAD_EN_BIT7)
1975 		return 0;
1976 
1977 	/* Update the Quad Enable bit. */
1978 	*sr2 |= SR2_QUAD_EN_BIT7;
1979 
1980 	ret = spi_nor_write_sr2(nor, sr2);
1981 	if (ret)
1982 		return ret;
1983 
1984 	sr2_written = *sr2;
1985 
1986 	/* Read back and check it. */
1987 	ret = spi_nor_read_sr2(nor, sr2);
1988 	if (ret)
1989 		return ret;
1990 
1991 	if (*sr2 != sr2_written) {
1992 		dev_dbg(nor->dev, "SR2: Read back test failed\n");
1993 		return -EIO;
1994 	}
1995 
1996 	return 0;
1997 }
1998 
1999 static const struct spi_nor_manufacturer *manufacturers[] = {
2000 	&spi_nor_atmel,
2001 	&spi_nor_eon,
2002 	&spi_nor_esmt,
2003 	&spi_nor_everspin,
2004 	&spi_nor_gigadevice,
2005 	&spi_nor_intel,
2006 	&spi_nor_issi,
2007 	&spi_nor_macronix,
2008 	&spi_nor_micron,
2009 	&spi_nor_st,
2010 	&spi_nor_spansion,
2011 	&spi_nor_sst,
2012 	&spi_nor_winbond,
2013 	&spi_nor_xilinx,
2014 	&spi_nor_xmc,
2015 };
2016 
2017 static const struct flash_info spi_nor_generic_flash = {
2018 	.name = "spi-nor-generic",
2019 };
2020 
2021 static const struct flash_info *spi_nor_match_id(struct spi_nor *nor,
2022 						 const u8 *id)
2023 {
2024 	const struct flash_info *part;
2025 	unsigned int i, j;
2026 
2027 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
2028 		for (j = 0; j < manufacturers[i]->nparts; j++) {
2029 			part = &manufacturers[i]->parts[j];
2030 			if (part->id &&
2031 			    !memcmp(part->id->bytes, id, part->id->len)) {
2032 				nor->manufacturer = manufacturers[i];
2033 				return part;
2034 			}
2035 		}
2036 	}
2037 
2038 	return NULL;
2039 }
2040 
2041 static const struct flash_info *spi_nor_detect(struct spi_nor *nor)
2042 {
2043 	const struct flash_info *info;
2044 	u8 *id = nor->bouncebuf;
2045 	int ret;
2046 
2047 	ret = spi_nor_read_id(nor, 0, 0, id, nor->reg_proto);
2048 	if (ret) {
2049 		dev_dbg(nor->dev, "error %d reading JEDEC ID\n", ret);
2050 		return ERR_PTR(ret);
2051 	}
2052 
2053 	/* Cache the complete flash ID. */
2054 	nor->id = devm_kmemdup(nor->dev, id, SPI_NOR_MAX_ID_LEN, GFP_KERNEL);
2055 	if (!nor->id)
2056 		return ERR_PTR(-ENOMEM);
2057 
2058 	info = spi_nor_match_id(nor, id);
2059 
2060 	/* Fallback to a generic flash described only by its SFDP data. */
2061 	if (!info) {
2062 		ret = spi_nor_check_sfdp_signature(nor);
2063 		if (!ret)
2064 			info = &spi_nor_generic_flash;
2065 	}
2066 
2067 	if (!info) {
2068 		dev_err(nor->dev, "unrecognized JEDEC id bytes: %*ph\n",
2069 			SPI_NOR_MAX_ID_LEN, id);
2070 		return ERR_PTR(-ENODEV);
2071 	}
2072 	return info;
2073 }
2074 
2075 static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
2076 			size_t *retlen, u_char *buf)
2077 {
2078 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2079 	loff_t from_lock = from;
2080 	size_t len_lock = len;
2081 	ssize_t ret;
2082 
2083 	dev_dbg(nor->dev, "from 0x%08x, len %zd\n", (u32)from, len);
2084 
2085 	ret = spi_nor_prep_and_lock_rd(nor, from_lock, len_lock);
2086 	if (ret)
2087 		return ret;
2088 
2089 	while (len) {
2090 		loff_t addr = from;
2091 
2092 		addr = spi_nor_convert_addr(nor, addr);
2093 
2094 		ret = spi_nor_read_data(nor, addr, len, buf);
2095 		if (ret == 0) {
2096 			/* We shouldn't see 0-length reads */
2097 			ret = -EIO;
2098 			goto read_err;
2099 		}
2100 		if (ret < 0)
2101 			goto read_err;
2102 
2103 		WARN_ON(ret > len);
2104 		*retlen += ret;
2105 		buf += ret;
2106 		from += ret;
2107 		len -= ret;
2108 	}
2109 	ret = 0;
2110 
2111 read_err:
2112 	spi_nor_unlock_and_unprep_rd(nor, from_lock, len_lock);
2113 
2114 	return ret;
2115 }
2116 
2117 /*
2118  * Write an address range to the nor chip.  Data must be written in
2119  * FLASH_PAGESIZE chunks.  The address range may be any size provided
2120  * it is within the physical boundaries.
2121  */
2122 static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
2123 	size_t *retlen, const u_char *buf)
2124 {
2125 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2126 	size_t page_offset, page_remain, i;
2127 	ssize_t ret;
2128 	u32 page_size = nor->params->page_size;
2129 
2130 	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
2131 
2132 	ret = spi_nor_prep_and_lock_pe(nor, to, len);
2133 	if (ret)
2134 		return ret;
2135 
2136 	for (i = 0; i < len; ) {
2137 		ssize_t written;
2138 		loff_t addr = to + i;
2139 
2140 		/*
2141 		 * If page_size is a power of two, the offset can be quickly
2142 		 * calculated with an AND operation. On the other cases we
2143 		 * need to do a modulus operation (more expensive).
2144 		 */
2145 		if (is_power_of_2(page_size)) {
2146 			page_offset = addr & (page_size - 1);
2147 		} else {
2148 			u64 aux = addr;
2149 
2150 			page_offset = do_div(aux, page_size);
2151 		}
2152 		/* the size of data remaining on the first page */
2153 		page_remain = min_t(size_t, page_size - page_offset, len - i);
2154 
2155 		addr = spi_nor_convert_addr(nor, addr);
2156 
2157 		ret = spi_nor_lock_device(nor);
2158 		if (ret)
2159 			goto write_err;
2160 
2161 		ret = spi_nor_write_enable(nor);
2162 		if (ret) {
2163 			spi_nor_unlock_device(nor);
2164 			goto write_err;
2165 		}
2166 
2167 		ret = spi_nor_write_data(nor, addr, page_remain, buf + i);
2168 		spi_nor_unlock_device(nor);
2169 		if (ret < 0)
2170 			goto write_err;
2171 		written = ret;
2172 
2173 		ret = spi_nor_wait_till_ready(nor);
2174 		if (ret)
2175 			goto write_err;
2176 		*retlen += written;
2177 		i += written;
2178 	}
2179 
2180 write_err:
2181 	spi_nor_unlock_and_unprep_pe(nor, to, len);
2182 
2183 	return ret;
2184 }
2185 
2186 static int spi_nor_check(struct spi_nor *nor)
2187 {
2188 	if (!nor->dev ||
2189 	    (!nor->spimem && !nor->controller_ops) ||
2190 	    (!nor->spimem && nor->controller_ops &&
2191 	    (!nor->controller_ops->read ||
2192 	     !nor->controller_ops->write ||
2193 	     !nor->controller_ops->read_reg ||
2194 	     !nor->controller_ops->write_reg))) {
2195 		pr_err("spi-nor: please fill all the necessary fields!\n");
2196 		return -EINVAL;
2197 	}
2198 
2199 	if (nor->spimem && nor->controller_ops) {
2200 		dev_err(nor->dev, "nor->spimem and nor->controller_ops are mutually exclusive, please set just one of them.\n");
2201 		return -EINVAL;
2202 	}
2203 
2204 	return 0;
2205 }
2206 
2207 void
2208 spi_nor_set_read_settings(struct spi_nor_read_command *read,
2209 			  u8 num_mode_clocks,
2210 			  u8 num_wait_states,
2211 			  u8 opcode,
2212 			  enum spi_nor_protocol proto)
2213 {
2214 	read->num_mode_clocks = num_mode_clocks;
2215 	read->num_wait_states = num_wait_states;
2216 	read->opcode = opcode;
2217 	read->proto = proto;
2218 }
2219 
2220 void spi_nor_set_pp_settings(struct spi_nor_pp_command *pp, u8 opcode,
2221 			     enum spi_nor_protocol proto)
2222 {
2223 	pp->opcode = opcode;
2224 	pp->proto = proto;
2225 }
2226 
2227 static int spi_nor_hwcaps2cmd(u32 hwcaps, const int table[][2], size_t size)
2228 {
2229 	size_t i;
2230 
2231 	for (i = 0; i < size; i++)
2232 		if (table[i][0] == (int)hwcaps)
2233 			return table[i][1];
2234 
2235 	return -EINVAL;
2236 }
2237 
2238 int spi_nor_hwcaps_read2cmd(u32 hwcaps)
2239 {
2240 	static const int hwcaps_read2cmd[][2] = {
2241 		{ SNOR_HWCAPS_READ,		SNOR_CMD_READ },
2242 		{ SNOR_HWCAPS_READ_FAST,	SNOR_CMD_READ_FAST },
2243 		{ SNOR_HWCAPS_READ_1_1_1_DTR,	SNOR_CMD_READ_1_1_1_DTR },
2244 		{ SNOR_HWCAPS_READ_1_1_2,	SNOR_CMD_READ_1_1_2 },
2245 		{ SNOR_HWCAPS_READ_1_2_2,	SNOR_CMD_READ_1_2_2 },
2246 		{ SNOR_HWCAPS_READ_2_2_2,	SNOR_CMD_READ_2_2_2 },
2247 		{ SNOR_HWCAPS_READ_1_2_2_DTR,	SNOR_CMD_READ_1_2_2_DTR },
2248 		{ SNOR_HWCAPS_READ_1_1_4,	SNOR_CMD_READ_1_1_4 },
2249 		{ SNOR_HWCAPS_READ_1_4_4,	SNOR_CMD_READ_1_4_4 },
2250 		{ SNOR_HWCAPS_READ_4_4_4,	SNOR_CMD_READ_4_4_4 },
2251 		{ SNOR_HWCAPS_READ_1_4_4_DTR,	SNOR_CMD_READ_1_4_4_DTR },
2252 		{ SNOR_HWCAPS_READ_1_1_8,	SNOR_CMD_READ_1_1_8 },
2253 		{ SNOR_HWCAPS_READ_1_8_8,	SNOR_CMD_READ_1_8_8 },
2254 		{ SNOR_HWCAPS_READ_8_8_8,	SNOR_CMD_READ_8_8_8 },
2255 		{ SNOR_HWCAPS_READ_1_8_8_DTR,	SNOR_CMD_READ_1_8_8_DTR },
2256 		{ SNOR_HWCAPS_READ_8_8_8_DTR,	SNOR_CMD_READ_8_8_8_DTR },
2257 	};
2258 
2259 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_read2cmd,
2260 				  ARRAY_SIZE(hwcaps_read2cmd));
2261 }
2262 
2263 int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
2264 {
2265 	static const int hwcaps_pp2cmd[][2] = {
2266 		{ SNOR_HWCAPS_PP,		SNOR_CMD_PP },
2267 		{ SNOR_HWCAPS_PP_1_1_4,		SNOR_CMD_PP_1_1_4 },
2268 		{ SNOR_HWCAPS_PP_1_4_4,		SNOR_CMD_PP_1_4_4 },
2269 		{ SNOR_HWCAPS_PP_4_4_4,		SNOR_CMD_PP_4_4_4 },
2270 		{ SNOR_HWCAPS_PP_1_1_8,		SNOR_CMD_PP_1_1_8 },
2271 		{ SNOR_HWCAPS_PP_1_8_8,		SNOR_CMD_PP_1_8_8 },
2272 		{ SNOR_HWCAPS_PP_8_8_8,		SNOR_CMD_PP_8_8_8 },
2273 		{ SNOR_HWCAPS_PP_8_8_8_DTR,	SNOR_CMD_PP_8_8_8_DTR },
2274 	};
2275 
2276 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_pp2cmd,
2277 				  ARRAY_SIZE(hwcaps_pp2cmd));
2278 }
2279 
2280 /**
2281  * spi_nor_spimem_check_op - check if the operation is supported
2282  *                           by controller
2283  *@nor:        pointer to a 'struct spi_nor'
2284  *@op:         pointer to op template to be checked
2285  *
2286  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2287  */
2288 static int spi_nor_spimem_check_op(struct spi_nor *nor,
2289 				   struct spi_mem_op *op)
2290 {
2291 	/*
2292 	 * First test with 4 address bytes. The opcode itself might
2293 	 * be a 3B addressing opcode but we don't care, because
2294 	 * SPI controller implementation should not check the opcode,
2295 	 * but just the sequence.
2296 	 */
2297 	op->addr.nbytes = 4;
2298 	if (!spi_mem_supports_op(nor->spimem, op)) {
2299 		if (nor->params->size > SZ_16M)
2300 			return -EOPNOTSUPP;
2301 
2302 		/* If flash size <= 16MB, 3 address bytes are sufficient */
2303 		op->addr.nbytes = 3;
2304 		if (!spi_mem_supports_op(nor->spimem, op))
2305 			return -EOPNOTSUPP;
2306 	}
2307 
2308 	return 0;
2309 }
2310 
2311 /**
2312  * spi_nor_spimem_check_readop - check if the read op is supported
2313  *                               by controller
2314  *@nor:         pointer to a 'struct spi_nor'
2315  *@read:        pointer to op template to be checked
2316  *
2317  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2318  */
2319 static int spi_nor_spimem_check_readop(struct spi_nor *nor,
2320 				       const struct spi_nor_read_command *read)
2321 {
2322 	struct spi_mem_op op = SPI_NOR_READ_OP(read->opcode);
2323 
2324 	spi_nor_spimem_setup_op(nor, &op, read->proto);
2325 
2326 	/* convert the dummy cycles to the number of bytes */
2327 	op.dummy.nbytes = (read->num_mode_clocks + read->num_wait_states) *
2328 			  op.dummy.buswidth / 8;
2329 	if (spi_nor_protocol_is_dtr(nor->read_proto))
2330 		op.dummy.nbytes *= 2;
2331 
2332 	return spi_nor_spimem_check_op(nor, &op);
2333 }
2334 
2335 /**
2336  * spi_nor_spimem_check_pp - check if the page program op is supported
2337  *                           by controller
2338  *@nor:         pointer to a 'struct spi_nor'
2339  *@pp:          pointer to op template to be checked
2340  *
2341  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2342  */
2343 static int spi_nor_spimem_check_pp(struct spi_nor *nor,
2344 				   const struct spi_nor_pp_command *pp)
2345 {
2346 	struct spi_mem_op op = SPI_NOR_PP_OP(pp->opcode);
2347 
2348 	spi_nor_spimem_setup_op(nor, &op, pp->proto);
2349 
2350 	return spi_nor_spimem_check_op(nor, &op);
2351 }
2352 
2353 /**
2354  * spi_nor_spimem_adjust_hwcaps - Find optimal Read/Write protocol
2355  *                                based on SPI controller capabilities
2356  * @nor:        pointer to a 'struct spi_nor'
2357  * @hwcaps:     pointer to resulting capabilities after adjusting
2358  *              according to controller and flash's capability
2359  */
2360 static void
2361 spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor, u32 *hwcaps)
2362 {
2363 	struct spi_nor_flash_parameter *params = nor->params;
2364 	unsigned int cap;
2365 
2366 	/* X-X-X modes are not supported yet, mask them all. */
2367 	*hwcaps &= ~SNOR_HWCAPS_X_X_X;
2368 
2369 	/*
2370 	 * If the reset line is broken, we do not want to enter a stateful
2371 	 * mode.
2372 	 */
2373 	if (nor->flags & SNOR_F_BROKEN_RESET)
2374 		*hwcaps &= ~(SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR);
2375 
2376 	for (cap = 0; cap < sizeof(*hwcaps) * BITS_PER_BYTE; cap++) {
2377 		int rdidx, ppidx;
2378 
2379 		if (!(*hwcaps & BIT(cap)))
2380 			continue;
2381 
2382 		rdidx = spi_nor_hwcaps_read2cmd(BIT(cap));
2383 		if (rdidx >= 0 &&
2384 		    spi_nor_spimem_check_readop(nor, &params->reads[rdidx]))
2385 			*hwcaps &= ~BIT(cap);
2386 
2387 		ppidx = spi_nor_hwcaps_pp2cmd(BIT(cap));
2388 		if (ppidx < 0)
2389 			continue;
2390 
2391 		if (spi_nor_spimem_check_pp(nor,
2392 					    &params->page_programs[ppidx]))
2393 			*hwcaps &= ~BIT(cap);
2394 	}
2395 }
2396 
2397 /**
2398  * spi_nor_set_erase_type() - set a SPI NOR erase type
2399  * @erase:	pointer to a structure that describes a SPI NOR erase type
2400  * @size:	the size of the sector/block erased by the erase type
2401  * @opcode:	the SPI command op code to erase the sector/block
2402  */
2403 void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
2404 			    u8 opcode)
2405 {
2406 	erase->size = size;
2407 	erase->opcode = opcode;
2408 	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
2409 	erase->size_shift = ffs(erase->size) - 1;
2410 	erase->size_mask = (1 << erase->size_shift) - 1;
2411 }
2412 
2413 /**
2414  * spi_nor_mask_erase_type() - mask out a SPI NOR erase type
2415  * @erase:	pointer to a structure that describes a SPI NOR erase type
2416  */
2417 void spi_nor_mask_erase_type(struct spi_nor_erase_type *erase)
2418 {
2419 	erase->size = 0;
2420 }
2421 
2422 /**
2423  * spi_nor_init_uniform_erase_map() - Initialize uniform erase map
2424  * @map:		the erase map of the SPI NOR
2425  * @erase_mask:		bitmask encoding erase types that can erase the entire
2426  *			flash memory
2427  * @flash_size:		the spi nor flash memory size
2428  */
2429 void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
2430 				    u8 erase_mask, u64 flash_size)
2431 {
2432 	/* Offset 0 with erase_mask and SNOR_LAST_REGION bit set */
2433 	map->uniform_region.offset = (erase_mask & SNOR_ERASE_TYPE_MASK) |
2434 				     SNOR_LAST_REGION;
2435 	map->uniform_region.size = flash_size;
2436 	map->regions = &map->uniform_region;
2437 	map->uniform_erase_type = erase_mask;
2438 }
2439 
2440 int spi_nor_post_bfpt_fixups(struct spi_nor *nor,
2441 			     const struct sfdp_parameter_header *bfpt_header,
2442 			     const struct sfdp_bfpt *bfpt)
2443 {
2444 	int ret;
2445 
2446 	if (nor->manufacturer && nor->manufacturer->fixups &&
2447 	    nor->manufacturer->fixups->post_bfpt) {
2448 		ret = nor->manufacturer->fixups->post_bfpt(nor, bfpt_header,
2449 							   bfpt);
2450 		if (ret)
2451 			return ret;
2452 	}
2453 
2454 	if (nor->info->fixups && nor->info->fixups->post_bfpt)
2455 		return nor->info->fixups->post_bfpt(nor, bfpt_header, bfpt);
2456 
2457 	return 0;
2458 }
2459 
2460 static int spi_nor_select_read(struct spi_nor *nor,
2461 			       u32 shared_hwcaps)
2462 {
2463 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_READ_MASK) - 1;
2464 	const struct spi_nor_read_command *read;
2465 
2466 	if (best_match < 0)
2467 		return -EINVAL;
2468 
2469 	cmd = spi_nor_hwcaps_read2cmd(BIT(best_match));
2470 	if (cmd < 0)
2471 		return -EINVAL;
2472 
2473 	read = &nor->params->reads[cmd];
2474 	nor->read_opcode = read->opcode;
2475 	nor->read_proto = read->proto;
2476 
2477 	/*
2478 	 * In the SPI NOR framework, we don't need to make the difference
2479 	 * between mode clock cycles and wait state clock cycles.
2480 	 * Indeed, the value of the mode clock cycles is used by a QSPI
2481 	 * flash memory to know whether it should enter or leave its 0-4-4
2482 	 * (Continuous Read / XIP) mode.
2483 	 * eXecution In Place is out of the scope of the mtd sub-system.
2484 	 * Hence we choose to merge both mode and wait state clock cycles
2485 	 * into the so called dummy clock cycles.
2486 	 */
2487 	nor->read_dummy = read->num_mode_clocks + read->num_wait_states;
2488 	return 0;
2489 }
2490 
2491 static int spi_nor_select_pp(struct spi_nor *nor,
2492 			     u32 shared_hwcaps)
2493 {
2494 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_PP_MASK) - 1;
2495 	const struct spi_nor_pp_command *pp;
2496 
2497 	if (best_match < 0)
2498 		return -EINVAL;
2499 
2500 	cmd = spi_nor_hwcaps_pp2cmd(BIT(best_match));
2501 	if (cmd < 0)
2502 		return -EINVAL;
2503 
2504 	pp = &nor->params->page_programs[cmd];
2505 	nor->program_opcode = pp->opcode;
2506 	nor->write_proto = pp->proto;
2507 	return 0;
2508 }
2509 
2510 /**
2511  * spi_nor_select_uniform_erase() - select optimum uniform erase type
2512  * @map:		the erase map of the SPI NOR
2513  *
2514  * Once the optimum uniform sector erase command is found, disable all the
2515  * other.
2516  *
2517  * Return: pointer to erase type on success, NULL otherwise.
2518  */
2519 static const struct spi_nor_erase_type *
2520 spi_nor_select_uniform_erase(struct spi_nor_erase_map *map)
2521 {
2522 	const struct spi_nor_erase_type *tested_erase, *erase = NULL;
2523 	int i;
2524 	u8 uniform_erase_type = map->uniform_erase_type;
2525 
2526 	/*
2527 	 * Search for the biggest erase size, except for when compiled
2528 	 * to use 4k erases.
2529 	 */
2530 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2531 		if (!(uniform_erase_type & BIT(i)))
2532 			continue;
2533 
2534 		tested_erase = &map->erase_type[i];
2535 
2536 		/* Skip masked erase types. */
2537 		if (!tested_erase->size)
2538 			continue;
2539 
2540 		/*
2541 		 * If the current erase size is the 4k one, stop here,
2542 		 * we have found the right uniform Sector Erase command.
2543 		 */
2544 		if (IS_ENABLED(CONFIG_MTD_SPI_NOR_USE_4K_SECTORS) &&
2545 		    tested_erase->size == SZ_4K) {
2546 			erase = tested_erase;
2547 			break;
2548 		}
2549 
2550 		/*
2551 		 * Otherwise, the current erase size is still a valid candidate.
2552 		 * Select the biggest valid candidate.
2553 		 */
2554 		if (!erase && tested_erase->size)
2555 			erase = tested_erase;
2556 			/* keep iterating to find the wanted_size */
2557 	}
2558 
2559 	if (!erase)
2560 		return NULL;
2561 
2562 	/* Disable all other Sector Erase commands. */
2563 	map->uniform_erase_type &= ~SNOR_ERASE_TYPE_MASK;
2564 	map->uniform_erase_type |= BIT(erase - map->erase_type);
2565 	return erase;
2566 }
2567 
2568 static int spi_nor_select_erase(struct spi_nor *nor)
2569 {
2570 	struct spi_nor_erase_map *map = &nor->params->erase_map;
2571 	const struct spi_nor_erase_type *erase = NULL;
2572 	struct mtd_info *mtd = &nor->mtd;
2573 	int i;
2574 
2575 	/*
2576 	 * The previous implementation handling Sector Erase commands assumed
2577 	 * that the SPI flash memory has an uniform layout then used only one
2578 	 * of the supported erase sizes for all Sector Erase commands.
2579 	 * So to be backward compatible, the new implementation also tries to
2580 	 * manage the SPI flash memory as uniform with a single erase sector
2581 	 * size, when possible.
2582 	 */
2583 	if (spi_nor_has_uniform_erase(nor)) {
2584 		erase = spi_nor_select_uniform_erase(map);
2585 		if (!erase)
2586 			return -EINVAL;
2587 		nor->erase_opcode = erase->opcode;
2588 		mtd->erasesize = erase->size;
2589 		return 0;
2590 	}
2591 
2592 	/*
2593 	 * For non-uniform SPI flash memory, set mtd->erasesize to the
2594 	 * maximum erase sector size. No need to set nor->erase_opcode.
2595 	 */
2596 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2597 		if (map->erase_type[i].size) {
2598 			erase = &map->erase_type[i];
2599 			break;
2600 		}
2601 	}
2602 
2603 	if (!erase)
2604 		return -EINVAL;
2605 
2606 	mtd->erasesize = erase->size;
2607 	return 0;
2608 }
2609 
2610 static int spi_nor_default_setup(struct spi_nor *nor,
2611 				 const struct spi_nor_hwcaps *hwcaps)
2612 {
2613 	struct spi_nor_flash_parameter *params = nor->params;
2614 	u32 ignored_mask, shared_mask;
2615 	int err;
2616 
2617 	/*
2618 	 * Keep only the hardware capabilities supported by both the SPI
2619 	 * controller and the SPI flash memory.
2620 	 */
2621 	shared_mask = hwcaps->mask & params->hwcaps.mask;
2622 
2623 	if (nor->spimem) {
2624 		/*
2625 		 * When called from spi_nor_probe(), all caps are set and we
2626 		 * need to discard some of them based on what the SPI
2627 		 * controller actually supports (using spi_mem_supports_op()).
2628 		 */
2629 		spi_nor_spimem_adjust_hwcaps(nor, &shared_mask);
2630 	} else {
2631 		/*
2632 		 * SPI n-n-n protocols are not supported when the SPI
2633 		 * controller directly implements the spi_nor interface.
2634 		 * Yet another reason to switch to spi-mem.
2635 		 */
2636 		ignored_mask = SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR;
2637 		if (shared_mask & ignored_mask) {
2638 			dev_dbg(nor->dev,
2639 				"SPI n-n-n protocols are not supported.\n");
2640 			shared_mask &= ~ignored_mask;
2641 		}
2642 	}
2643 
2644 	/* Select the (Fast) Read command. */
2645 	err = spi_nor_select_read(nor, shared_mask);
2646 	if (err) {
2647 		dev_dbg(nor->dev,
2648 			"can't select read settings supported by both the SPI controller and memory.\n");
2649 		return err;
2650 	}
2651 
2652 	/* Select the Page Program command. */
2653 	err = spi_nor_select_pp(nor, shared_mask);
2654 	if (err) {
2655 		dev_dbg(nor->dev,
2656 			"can't select write settings supported by both the SPI controller and memory.\n");
2657 		return err;
2658 	}
2659 
2660 	/* Select the Sector Erase command. */
2661 	err = spi_nor_select_erase(nor);
2662 	if (err) {
2663 		dev_dbg(nor->dev,
2664 			"can't select erase settings supported by both the SPI controller and memory.\n");
2665 		return err;
2666 	}
2667 
2668 	return 0;
2669 }
2670 
2671 static int spi_nor_set_addr_nbytes(struct spi_nor *nor)
2672 {
2673 	if (nor->params->addr_nbytes) {
2674 		nor->addr_nbytes = nor->params->addr_nbytes;
2675 	} else if (nor->read_proto == SNOR_PROTO_8_8_8_DTR) {
2676 		/*
2677 		 * In 8D-8D-8D mode, one byte takes half a cycle to transfer. So
2678 		 * in this protocol an odd addr_nbytes cannot be used because
2679 		 * then the address phase would only span a cycle and a half.
2680 		 * Half a cycle would be left over. We would then have to start
2681 		 * the dummy phase in the middle of a cycle and so too the data
2682 		 * phase, and we will end the transaction with half a cycle left
2683 		 * over.
2684 		 *
2685 		 * Force all 8D-8D-8D flashes to use an addr_nbytes of 4 to
2686 		 * avoid this situation.
2687 		 */
2688 		nor->addr_nbytes = 4;
2689 	} else if (nor->info->addr_nbytes) {
2690 		nor->addr_nbytes = nor->info->addr_nbytes;
2691 	} else {
2692 		nor->addr_nbytes = 3;
2693 	}
2694 
2695 	if (nor->addr_nbytes == 3 && nor->params->size > 0x1000000) {
2696 		/* enable 4-byte addressing if the device exceeds 16MiB */
2697 		nor->addr_nbytes = 4;
2698 	}
2699 
2700 	if (nor->addr_nbytes > SPI_NOR_MAX_ADDR_NBYTES) {
2701 		dev_dbg(nor->dev, "The number of address bytes is too large: %u\n",
2702 			nor->addr_nbytes);
2703 		return -EINVAL;
2704 	}
2705 
2706 	/* Set 4byte opcodes when possible. */
2707 	if (nor->addr_nbytes == 4 && nor->flags & SNOR_F_4B_OPCODES &&
2708 	    !(nor->flags & SNOR_F_HAS_4BAIT))
2709 		spi_nor_set_4byte_opcodes(nor);
2710 
2711 	return 0;
2712 }
2713 
2714 static int spi_nor_setup(struct spi_nor *nor,
2715 			 const struct spi_nor_hwcaps *hwcaps)
2716 {
2717 	int ret;
2718 
2719 	if (nor->params->setup)
2720 		ret = nor->params->setup(nor, hwcaps);
2721 	else
2722 		ret = spi_nor_default_setup(nor, hwcaps);
2723 	if (ret)
2724 		return ret;
2725 
2726 	return spi_nor_set_addr_nbytes(nor);
2727 }
2728 
2729 /**
2730  * spi_nor_manufacturer_init_params() - Initialize the flash's parameters and
2731  * settings based on MFR register and ->default_init() hook.
2732  * @nor:	pointer to a 'struct spi_nor'.
2733  */
2734 static void spi_nor_manufacturer_init_params(struct spi_nor *nor)
2735 {
2736 	if (nor->manufacturer && nor->manufacturer->fixups &&
2737 	    nor->manufacturer->fixups->default_init)
2738 		nor->manufacturer->fixups->default_init(nor);
2739 
2740 	if (nor->info->fixups && nor->info->fixups->default_init)
2741 		nor->info->fixups->default_init(nor);
2742 }
2743 
2744 /**
2745  * spi_nor_no_sfdp_init_params() - Initialize the flash's parameters and
2746  * settings based on nor->info->sfdp_flags. This method should be called only by
2747  * flashes that do not define SFDP tables. If the flash supports SFDP but the
2748  * information is wrong and the settings from this function can not be retrieved
2749  * by parsing SFDP, one should instead use the fixup hooks and update the wrong
2750  * bits.
2751  * @nor:	pointer to a 'struct spi_nor'.
2752  */
2753 static void spi_nor_no_sfdp_init_params(struct spi_nor *nor)
2754 {
2755 	struct spi_nor_flash_parameter *params = nor->params;
2756 	struct spi_nor_erase_map *map = &params->erase_map;
2757 	const struct flash_info *info = nor->info;
2758 	const u8 no_sfdp_flags = info->no_sfdp_flags;
2759 	u8 i, erase_mask;
2760 
2761 	if (no_sfdp_flags & SPI_NOR_DUAL_READ) {
2762 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
2763 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_2],
2764 					  0, 8, SPINOR_OP_READ_1_1_2,
2765 					  SNOR_PROTO_1_1_2);
2766 	}
2767 
2768 	if (no_sfdp_flags & SPI_NOR_QUAD_READ) {
2769 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
2770 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_4],
2771 					  0, 8, SPINOR_OP_READ_1_1_4,
2772 					  SNOR_PROTO_1_1_4);
2773 	}
2774 
2775 	if (no_sfdp_flags & SPI_NOR_OCTAL_READ) {
2776 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
2777 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
2778 					  0, 8, SPINOR_OP_READ_1_1_8,
2779 					  SNOR_PROTO_1_1_8);
2780 	}
2781 
2782 	if (no_sfdp_flags & SPI_NOR_OCTAL_DTR_READ) {
2783 		params->hwcaps.mask |= SNOR_HWCAPS_READ_8_8_8_DTR;
2784 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_8_8_8_DTR],
2785 					  0, 20, SPINOR_OP_READ_FAST,
2786 					  SNOR_PROTO_8_8_8_DTR);
2787 	}
2788 
2789 	if (no_sfdp_flags & SPI_NOR_OCTAL_DTR_PP) {
2790 		params->hwcaps.mask |= SNOR_HWCAPS_PP_8_8_8_DTR;
2791 		/*
2792 		 * Since xSPI Page Program opcode is backward compatible with
2793 		 * Legacy SPI, use Legacy SPI opcode there as well.
2794 		 */
2795 		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_8_8_8_DTR],
2796 					SPINOR_OP_PP, SNOR_PROTO_8_8_8_DTR);
2797 	}
2798 
2799 	/*
2800 	 * Sector Erase settings. Sort Erase Types in ascending order, with the
2801 	 * smallest erase size starting at BIT(0).
2802 	 */
2803 	erase_mask = 0;
2804 	i = 0;
2805 	if (no_sfdp_flags & SECT_4K) {
2806 		erase_mask |= BIT(i);
2807 		spi_nor_set_erase_type(&map->erase_type[i], 4096u,
2808 				       SPINOR_OP_BE_4K);
2809 		i++;
2810 	}
2811 	erase_mask |= BIT(i);
2812 	spi_nor_set_erase_type(&map->erase_type[i],
2813 			       info->sector_size ?: SPI_NOR_DEFAULT_SECTOR_SIZE,
2814 			       SPINOR_OP_SE);
2815 	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
2816 }
2817 
2818 /**
2819  * spi_nor_init_flags() - Initialize NOR flags for settings that are not defined
2820  * in the JESD216 SFDP standard, thus can not be retrieved when parsing SFDP.
2821  * @nor:	pointer to a 'struct spi_nor'
2822  */
2823 static void spi_nor_init_flags(struct spi_nor *nor)
2824 {
2825 	struct device_node *np = spi_nor_get_flash_node(nor);
2826 	const u16 flags = nor->info->flags;
2827 
2828 	if (of_property_read_bool(np, "broken-flash-reset"))
2829 		nor->flags |= SNOR_F_BROKEN_RESET;
2830 
2831 	if (of_property_read_bool(np, "no-wp"))
2832 		nor->flags |= SNOR_F_NO_WP;
2833 
2834 	if (flags & SPI_NOR_SWP_IS_VOLATILE)
2835 		nor->flags |= SNOR_F_SWP_IS_VOLATILE;
2836 
2837 	if (flags & SPI_NOR_HAS_LOCK)
2838 		nor->flags |= SNOR_F_HAS_LOCK;
2839 
2840 	if (flags & SPI_NOR_HAS_TB) {
2841 		nor->flags |= SNOR_F_HAS_SR_TB;
2842 		if (flags & SPI_NOR_TB_SR_BIT6)
2843 			nor->flags |= SNOR_F_HAS_SR_TB_BIT6;
2844 	}
2845 
2846 	if (flags & SPI_NOR_4BIT_BP) {
2847 		nor->flags |= SNOR_F_HAS_4BIT_BP;
2848 		if (flags & SPI_NOR_BP3_SR_BIT6)
2849 			nor->flags |= SNOR_F_HAS_SR_BP3_BIT6;
2850 	}
2851 
2852 	if (flags & NO_CHIP_ERASE)
2853 		nor->flags |= SNOR_F_NO_OP_CHIP_ERASE;
2854 
2855 	if (flags & SPI_NOR_RWW && nor->params->n_banks > 1 &&
2856 	    !nor->controller_ops)
2857 		nor->flags |= SNOR_F_RWW;
2858 }
2859 
2860 /**
2861  * spi_nor_init_fixup_flags() - Initialize NOR flags for settings that can not
2862  * be discovered by SFDP for this particular flash because the SFDP table that
2863  * indicates this support is not defined in the flash. In case the table for
2864  * this support is defined but has wrong values, one should instead use a
2865  * post_sfdp() hook to set the SNOR_F equivalent flag.
2866  * @nor:       pointer to a 'struct spi_nor'
2867  */
2868 static void spi_nor_init_fixup_flags(struct spi_nor *nor)
2869 {
2870 	const u8 fixup_flags = nor->info->fixup_flags;
2871 
2872 	if (fixup_flags & SPI_NOR_4B_OPCODES)
2873 		nor->flags |= SNOR_F_4B_OPCODES;
2874 
2875 	if (fixup_flags & SPI_NOR_IO_MODE_EN_VOLATILE)
2876 		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;
2877 }
2878 
2879 /**
2880  * spi_nor_late_init_params() - Late initialization of default flash parameters.
2881  * @nor:	pointer to a 'struct spi_nor'
2882  *
2883  * Used to initialize flash parameters that are not declared in the JESD216
2884  * SFDP standard, or where SFDP tables are not defined at all.
2885  * Will replace the spi_nor_manufacturer_init_params() method.
2886  */
2887 static int spi_nor_late_init_params(struct spi_nor *nor)
2888 {
2889 	struct spi_nor_flash_parameter *params = nor->params;
2890 	int ret;
2891 
2892 	if (nor->manufacturer && nor->manufacturer->fixups &&
2893 	    nor->manufacturer->fixups->late_init) {
2894 		ret = nor->manufacturer->fixups->late_init(nor);
2895 		if (ret)
2896 			return ret;
2897 	}
2898 
2899 	if (nor->info->fixups && nor->info->fixups->late_init) {
2900 		ret = nor->info->fixups->late_init(nor);
2901 		if (ret)
2902 			return ret;
2903 	}
2904 
2905 	/* Default method kept for backward compatibility. */
2906 	if (!params->set_4byte_addr_mode)
2907 		params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_brwr;
2908 
2909 	spi_nor_init_flags(nor);
2910 	spi_nor_init_fixup_flags(nor);
2911 
2912 	/*
2913 	 * NOR protection support. When locking_ops are not provided, we pick
2914 	 * the default ones.
2915 	 */
2916 	if (nor->flags & SNOR_F_HAS_LOCK && !nor->params->locking_ops)
2917 		spi_nor_init_default_locking_ops(nor);
2918 
2919 	if (params->n_banks > 1)
2920 		params->bank_size = div64_u64(params->size, params->n_banks);
2921 
2922 	return 0;
2923 }
2924 
2925 /**
2926  * spi_nor_sfdp_init_params_deprecated() - Deprecated way of initializing flash
2927  * parameters and settings based on JESD216 SFDP standard.
2928  * @nor:	pointer to a 'struct spi_nor'.
2929  *
2930  * The method has a roll-back mechanism: in case the SFDP parsing fails, the
2931  * legacy flash parameters and settings will be restored.
2932  */
2933 static void spi_nor_sfdp_init_params_deprecated(struct spi_nor *nor)
2934 {
2935 	struct spi_nor_flash_parameter sfdp_params;
2936 
2937 	memcpy(&sfdp_params, nor->params, sizeof(sfdp_params));
2938 
2939 	if (spi_nor_parse_sfdp(nor)) {
2940 		memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
2941 		nor->flags &= ~SNOR_F_4B_OPCODES;
2942 	}
2943 }
2944 
2945 /**
2946  * spi_nor_init_params_deprecated() - Deprecated way of initializing flash
2947  * parameters and settings.
2948  * @nor:	pointer to a 'struct spi_nor'.
2949  *
2950  * The method assumes that flash doesn't support SFDP so it initializes flash
2951  * parameters in spi_nor_no_sfdp_init_params() which later on can be overwritten
2952  * when parsing SFDP, if supported.
2953  */
2954 static void spi_nor_init_params_deprecated(struct spi_nor *nor)
2955 {
2956 	spi_nor_no_sfdp_init_params(nor);
2957 
2958 	spi_nor_manufacturer_init_params(nor);
2959 
2960 	if (nor->info->no_sfdp_flags & (SPI_NOR_DUAL_READ |
2961 					SPI_NOR_QUAD_READ |
2962 					SPI_NOR_OCTAL_READ |
2963 					SPI_NOR_OCTAL_DTR_READ))
2964 		spi_nor_sfdp_init_params_deprecated(nor);
2965 }
2966 
2967 /**
2968  * spi_nor_init_default_params() - Default initialization of flash parameters
2969  * and settings. Done for all flashes, regardless is they define SFDP tables
2970  * or not.
2971  * @nor:	pointer to a 'struct spi_nor'.
2972  */
2973 static void spi_nor_init_default_params(struct spi_nor *nor)
2974 {
2975 	struct spi_nor_flash_parameter *params = nor->params;
2976 	const struct flash_info *info = nor->info;
2977 	struct device_node *np = spi_nor_get_flash_node(nor);
2978 
2979 	params->quad_enable = spi_nor_sr2_bit1_quad_enable;
2980 	params->otp.org = info->otp;
2981 
2982 	/* Default to 16-bit Write Status (01h) Command */
2983 	nor->flags |= SNOR_F_HAS_16BIT_SR;
2984 
2985 	/* Set SPI NOR sizes. */
2986 	params->writesize = 1;
2987 	params->size = info->size;
2988 	params->bank_size = params->size;
2989 	params->page_size = info->page_size ?: SPI_NOR_DEFAULT_PAGE_SIZE;
2990 	params->n_banks = info->n_banks ?: SPI_NOR_DEFAULT_N_BANKS;
2991 
2992 	if (!(info->flags & SPI_NOR_NO_FR)) {
2993 		/* Default to Fast Read for DT and non-DT platform devices. */
2994 		params->hwcaps.mask |= SNOR_HWCAPS_READ_FAST;
2995 
2996 		/* Mask out Fast Read if not requested at DT instantiation. */
2997 		if (np && !of_property_read_bool(np, "m25p,fast-read"))
2998 			params->hwcaps.mask &= ~SNOR_HWCAPS_READ_FAST;
2999 	}
3000 
3001 	/* (Fast) Read settings. */
3002 	params->hwcaps.mask |= SNOR_HWCAPS_READ;
3003 	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ],
3004 				  0, 0, SPINOR_OP_READ,
3005 				  SNOR_PROTO_1_1_1);
3006 
3007 	if (params->hwcaps.mask & SNOR_HWCAPS_READ_FAST)
3008 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_FAST],
3009 					  0, 8, SPINOR_OP_READ_FAST,
3010 					  SNOR_PROTO_1_1_1);
3011 	/* Page Program settings. */
3012 	params->hwcaps.mask |= SNOR_HWCAPS_PP;
3013 	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP],
3014 				SPINOR_OP_PP, SNOR_PROTO_1_1_1);
3015 
3016 	if (info->flags & SPI_NOR_QUAD_PP) {
3017 		params->hwcaps.mask |= SNOR_HWCAPS_PP_1_1_4;
3018 		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_1_1_4],
3019 					SPINOR_OP_PP_1_1_4, SNOR_PROTO_1_1_4);
3020 	}
3021 }
3022 
3023 /**
3024  * spi_nor_init_params() - Initialize the flash's parameters and settings.
3025  * @nor:	pointer to a 'struct spi_nor'.
3026  *
3027  * The flash parameters and settings are initialized based on a sequence of
3028  * calls that are ordered by priority:
3029  *
3030  * 1/ Default flash parameters initialization. The initializations are done
3031  *    based on nor->info data:
3032  *		spi_nor_info_init_params()
3033  *
3034  * which can be overwritten by:
3035  * 2/ Manufacturer flash parameters initialization. The initializations are
3036  *    done based on MFR register, or when the decisions can not be done solely
3037  *    based on MFR, by using specific flash_info tweeks, ->default_init():
3038  *		spi_nor_manufacturer_init_params()
3039  *
3040  * which can be overwritten by:
3041  * 3/ SFDP flash parameters initialization. JESD216 SFDP is a standard and
3042  *    should be more accurate that the above.
3043  *		spi_nor_parse_sfdp() or spi_nor_no_sfdp_init_params()
3044  *
3045  *    Please note that there is a ->post_bfpt() fixup hook that can overwrite
3046  *    the flash parameters and settings immediately after parsing the Basic
3047  *    Flash Parameter Table.
3048  *    spi_nor_post_sfdp_fixups() is called after the SFDP tables are parsed.
3049  *    It is used to tweak various flash parameters when information provided
3050  *    by the SFDP tables are wrong.
3051  *
3052  * which can be overwritten by:
3053  * 4/ Late flash parameters initialization, used to initialize flash
3054  * parameters that are not declared in the JESD216 SFDP standard, or where SFDP
3055  * tables are not defined at all.
3056  *		spi_nor_late_init_params()
3057  *
3058  * Return: 0 on success, -errno otherwise.
3059  */
3060 static int spi_nor_init_params(struct spi_nor *nor)
3061 {
3062 	int ret;
3063 
3064 	nor->params = devm_kzalloc(nor->dev, sizeof(*nor->params), GFP_KERNEL);
3065 	if (!nor->params)
3066 		return -ENOMEM;
3067 
3068 	spi_nor_init_default_params(nor);
3069 
3070 	if (spi_nor_needs_sfdp(nor)) {
3071 		ret = spi_nor_parse_sfdp(nor);
3072 		if (ret) {
3073 			dev_err(nor->dev, "BFPT parsing failed. Please consider using SPI_NOR_SKIP_SFDP when declaring the flash\n");
3074 			return ret;
3075 		}
3076 	} else if (nor->info->no_sfdp_flags & SPI_NOR_SKIP_SFDP) {
3077 		spi_nor_no_sfdp_init_params(nor);
3078 	} else {
3079 		spi_nor_init_params_deprecated(nor);
3080 	}
3081 
3082 	return spi_nor_late_init_params(nor);
3083 }
3084 
3085 /** spi_nor_set_octal_dtr() - enable or disable Octal DTR I/O.
3086  * @nor:                 pointer to a 'struct spi_nor'
3087  * @enable:              whether to enable or disable Octal DTR
3088  *
3089  * Return: 0 on success, -errno otherwise.
3090  */
3091 static int spi_nor_set_octal_dtr(struct spi_nor *nor, bool enable)
3092 {
3093 	int ret;
3094 
3095 	if (!nor->params->set_octal_dtr)
3096 		return 0;
3097 
3098 	if (!(nor->read_proto == SNOR_PROTO_8_8_8_DTR &&
3099 	      nor->write_proto == SNOR_PROTO_8_8_8_DTR))
3100 		return 0;
3101 
3102 	if (!(nor->flags & SNOR_F_IO_MODE_EN_VOLATILE))
3103 		return 0;
3104 
3105 	ret = nor->params->set_octal_dtr(nor, enable);
3106 	if (ret)
3107 		return ret;
3108 
3109 	if (enable)
3110 		nor->reg_proto = SNOR_PROTO_8_8_8_DTR;
3111 	else
3112 		nor->reg_proto = SNOR_PROTO_1_1_1;
3113 
3114 	return 0;
3115 }
3116 
3117 /**
3118  * spi_nor_quad_enable() - enable Quad I/O if needed.
3119  * @nor:                pointer to a 'struct spi_nor'
3120  *
3121  * Return: 0 on success, -errno otherwise.
3122  */
3123 static int spi_nor_quad_enable(struct spi_nor *nor)
3124 {
3125 	if (!nor->params->quad_enable)
3126 		return 0;
3127 
3128 	if (!(spi_nor_get_protocol_width(nor->read_proto) == 4 ||
3129 	      spi_nor_get_protocol_width(nor->write_proto) == 4))
3130 		return 0;
3131 
3132 	return nor->params->quad_enable(nor);
3133 }
3134 
3135 /**
3136  * spi_nor_set_4byte_addr_mode() - Set address mode.
3137  * @nor:                pointer to a 'struct spi_nor'.
3138  * @enable:             enable/disable 4 byte address mode.
3139  *
3140  * Return: 0 on success, -errno otherwise.
3141  */
3142 int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
3143 {
3144 	struct spi_nor_flash_parameter *params = nor->params;
3145 	int ret;
3146 
3147 	ret = params->set_4byte_addr_mode(nor, enable);
3148 	if (ret && ret != -ENOTSUPP)
3149 		return ret;
3150 
3151 	if (enable) {
3152 		params->addr_nbytes = 4;
3153 		params->addr_mode_nbytes = 4;
3154 	} else {
3155 		params->addr_nbytes = 3;
3156 		params->addr_mode_nbytes = 3;
3157 	}
3158 
3159 	return 0;
3160 }
3161 
3162 static int spi_nor_init(struct spi_nor *nor)
3163 {
3164 	int err;
3165 
3166 	err = spi_nor_set_octal_dtr(nor, true);
3167 	if (err) {
3168 		dev_dbg(nor->dev, "octal mode not supported\n");
3169 		return err;
3170 	}
3171 
3172 	err = spi_nor_quad_enable(nor);
3173 	if (err) {
3174 		dev_dbg(nor->dev, "quad mode not supported\n");
3175 		return err;
3176 	}
3177 
3178 	/*
3179 	 * Some SPI NOR flashes are write protected by default after a power-on
3180 	 * reset cycle, in order to avoid inadvertent writes during power-up.
3181 	 * Backward compatibility imposes to unlock the entire flash memory
3182 	 * array at power-up by default. Depending on the kernel configuration
3183 	 * (1) do nothing, (2) always unlock the entire flash array or (3)
3184 	 * unlock the entire flash array only when the software write
3185 	 * protection bits are volatile. The latter is indicated by
3186 	 * SNOR_F_SWP_IS_VOLATILE.
3187 	 */
3188 	if (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE) ||
3189 	    (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE_ON_VOLATILE) &&
3190 	     nor->flags & SNOR_F_SWP_IS_VOLATILE))
3191 		spi_nor_try_unlock_all(nor);
3192 
3193 	if (nor->addr_nbytes == 4 &&
3194 	    nor->read_proto != SNOR_PROTO_8_8_8_DTR &&
3195 	    !(nor->flags & SNOR_F_4B_OPCODES)) {
3196 		/*
3197 		 * If the RESET# pin isn't hooked up properly, or the system
3198 		 * otherwise doesn't perform a reset command in the boot
3199 		 * sequence, it's impossible to 100% protect against unexpected
3200 		 * reboots (e.g., crashes). Warn the user (or hopefully, system
3201 		 * designer) that this is bad.
3202 		 */
3203 		WARN_ONCE(nor->flags & SNOR_F_BROKEN_RESET,
3204 			  "enabling reset hack; may not recover from unexpected reboots\n");
3205 		err = spi_nor_set_4byte_addr_mode(nor, true);
3206 		if (err)
3207 			return err;
3208 	}
3209 
3210 	return 0;
3211 }
3212 
3213 /**
3214  * spi_nor_soft_reset() - Perform a software reset
3215  * @nor:	pointer to 'struct spi_nor'
3216  *
3217  * Performs a "Soft Reset and Enter Default Protocol Mode" sequence which resets
3218  * the device to its power-on-reset state. This is useful when the software has
3219  * made some changes to device (volatile) registers and needs to reset it before
3220  * shutting down, for example.
3221  *
3222  * Not every flash supports this sequence. The same set of opcodes might be used
3223  * for some other operation on a flash that does not support this. Support for
3224  * this sequence can be discovered via SFDP in the BFPT table.
3225  *
3226  * Return: 0 on success, -errno otherwise.
3227  */
3228 static void spi_nor_soft_reset(struct spi_nor *nor)
3229 {
3230 	struct spi_mem_op op;
3231 	int ret;
3232 
3233 	op = (struct spi_mem_op)SPINOR_SRSTEN_OP;
3234 
3235 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3236 
3237 	ret = spi_mem_exec_op(nor->spimem, &op);
3238 	if (ret) {
3239 		dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3240 		return;
3241 	}
3242 
3243 	op = (struct spi_mem_op)SPINOR_SRST_OP;
3244 
3245 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3246 
3247 	ret = spi_mem_exec_op(nor->spimem, &op);
3248 	if (ret) {
3249 		dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3250 		return;
3251 	}
3252 
3253 	/*
3254 	 * Software Reset is not instant, and the delay varies from flash to
3255 	 * flash. Looking at a few flashes, most range somewhere below 100
3256 	 * microseconds. So, sleep for a range of 200-400 us.
3257 	 */
3258 	usleep_range(SPI_NOR_SRST_SLEEP_MIN, SPI_NOR_SRST_SLEEP_MAX);
3259 }
3260 
3261 /* mtd suspend handler */
3262 static int spi_nor_suspend(struct mtd_info *mtd)
3263 {
3264 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3265 	int ret;
3266 
3267 	/* Disable octal DTR mode if we enabled it. */
3268 	ret = spi_nor_set_octal_dtr(nor, false);
3269 	if (ret)
3270 		dev_err(nor->dev, "suspend() failed\n");
3271 
3272 	return ret;
3273 }
3274 
3275 /* mtd resume handler */
3276 static void spi_nor_resume(struct mtd_info *mtd)
3277 {
3278 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3279 	struct device *dev = nor->dev;
3280 	int ret;
3281 
3282 	/* re-initialize the nor chip */
3283 	ret = spi_nor_init(nor);
3284 	if (ret)
3285 		dev_err(dev, "resume() failed\n");
3286 }
3287 
3288 static int spi_nor_get_device(struct mtd_info *mtd)
3289 {
3290 	struct mtd_info *master = mtd_get_master(mtd);
3291 	struct spi_nor *nor = mtd_to_spi_nor(master);
3292 	struct device *dev;
3293 
3294 	if (nor->spimem)
3295 		dev = nor->spimem->spi->controller->dev.parent;
3296 	else
3297 		dev = nor->dev;
3298 
3299 	if (!try_module_get(dev->driver->owner))
3300 		return -ENODEV;
3301 
3302 	return 0;
3303 }
3304 
3305 static void spi_nor_put_device(struct mtd_info *mtd)
3306 {
3307 	struct mtd_info *master = mtd_get_master(mtd);
3308 	struct spi_nor *nor = mtd_to_spi_nor(master);
3309 	struct device *dev;
3310 
3311 	if (nor->spimem)
3312 		dev = nor->spimem->spi->controller->dev.parent;
3313 	else
3314 		dev = nor->dev;
3315 
3316 	module_put(dev->driver->owner);
3317 }
3318 
3319 static void spi_nor_restore(struct spi_nor *nor)
3320 {
3321 	int ret;
3322 
3323 	/* restore the addressing mode */
3324 	if (nor->addr_nbytes == 4 && !(nor->flags & SNOR_F_4B_OPCODES) &&
3325 	    nor->flags & SNOR_F_BROKEN_RESET) {
3326 		ret = spi_nor_set_4byte_addr_mode(nor, false);
3327 		if (ret)
3328 			/*
3329 			 * Do not stop the execution in the hope that the flash
3330 			 * will default to the 3-byte address mode after the
3331 			 * software reset.
3332 			 */
3333 			dev_err(nor->dev, "Failed to exit 4-byte address mode, err = %d\n", ret);
3334 	}
3335 
3336 	if (nor->flags & SNOR_F_SOFT_RESET)
3337 		spi_nor_soft_reset(nor);
3338 }
3339 
3340 static const struct flash_info *spi_nor_match_name(struct spi_nor *nor,
3341 						   const char *name)
3342 {
3343 	unsigned int i, j;
3344 
3345 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
3346 		for (j = 0; j < manufacturers[i]->nparts; j++) {
3347 			if (!strcmp(name, manufacturers[i]->parts[j].name)) {
3348 				nor->manufacturer = manufacturers[i];
3349 				return &manufacturers[i]->parts[j];
3350 			}
3351 		}
3352 	}
3353 
3354 	return NULL;
3355 }
3356 
3357 static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
3358 						       const char *name)
3359 {
3360 	const struct flash_info *info = NULL;
3361 
3362 	if (name)
3363 		info = spi_nor_match_name(nor, name);
3364 	/* Try to auto-detect if chip name wasn't specified or not found */
3365 	if (!info)
3366 		return spi_nor_detect(nor);
3367 
3368 	/*
3369 	 * If caller has specified name of flash model that can normally be
3370 	 * detected using JEDEC, let's verify it.
3371 	 */
3372 	if (name && info->id) {
3373 		const struct flash_info *jinfo;
3374 
3375 		jinfo = spi_nor_detect(nor);
3376 		if (IS_ERR(jinfo)) {
3377 			return jinfo;
3378 		} else if (jinfo != info) {
3379 			/*
3380 			 * JEDEC knows better, so overwrite platform ID. We
3381 			 * can't trust partitions any longer, but we'll let
3382 			 * mtd apply them anyway, since some partitions may be
3383 			 * marked read-only, and we don't want to loose that
3384 			 * information, even if it's not 100% accurate.
3385 			 */
3386 			dev_warn(nor->dev, "found %s, expected %s\n",
3387 				 jinfo->name, info->name);
3388 			info = jinfo;
3389 		}
3390 	}
3391 
3392 	return info;
3393 }
3394 
3395 static void spi_nor_set_mtd_info(struct spi_nor *nor)
3396 {
3397 	struct mtd_info *mtd = &nor->mtd;
3398 	struct device *dev = nor->dev;
3399 
3400 	spi_nor_set_mtd_locking_ops(nor);
3401 	spi_nor_set_mtd_otp_ops(nor);
3402 
3403 	mtd->dev.parent = dev;
3404 	if (!mtd->name)
3405 		mtd->name = dev_name(dev);
3406 	mtd->type = MTD_NORFLASH;
3407 	mtd->flags = MTD_CAP_NORFLASH;
3408 	/* Unset BIT_WRITEABLE to enable JFFS2 write buffer for ECC'd NOR */
3409 	if (nor->flags & SNOR_F_ECC)
3410 		mtd->flags &= ~MTD_BIT_WRITEABLE;
3411 	if (nor->info->flags & SPI_NOR_NO_ERASE)
3412 		mtd->flags |= MTD_NO_ERASE;
3413 	else
3414 		mtd->_erase = spi_nor_erase;
3415 	mtd->writesize = nor->params->writesize;
3416 	mtd->writebufsize = nor->params->page_size;
3417 	mtd->size = nor->params->size;
3418 	mtd->_read = spi_nor_read;
3419 	/* Might be already set by some SST flashes. */
3420 	if (!mtd->_write)
3421 		mtd->_write = spi_nor_write;
3422 	mtd->_suspend = spi_nor_suspend;
3423 	mtd->_resume = spi_nor_resume;
3424 	mtd->_get_device = spi_nor_get_device;
3425 	mtd->_put_device = spi_nor_put_device;
3426 }
3427 
3428 static int spi_nor_hw_reset(struct spi_nor *nor)
3429 {
3430 	struct gpio_desc *reset;
3431 
3432 	reset = devm_gpiod_get_optional(nor->dev, "reset", GPIOD_OUT_LOW);
3433 	if (IS_ERR_OR_NULL(reset))
3434 		return PTR_ERR_OR_ZERO(reset);
3435 
3436 	/*
3437 	 * Experimental delay values by looking at different flash device
3438 	 * vendors datasheets.
3439 	 */
3440 	usleep_range(1, 5);
3441 	gpiod_set_value_cansleep(reset, 1);
3442 	usleep_range(100, 150);
3443 	gpiod_set_value_cansleep(reset, 0);
3444 	usleep_range(1000, 1200);
3445 
3446 	return 0;
3447 }
3448 
3449 int spi_nor_scan(struct spi_nor *nor, const char *name,
3450 		 const struct spi_nor_hwcaps *hwcaps)
3451 {
3452 	const struct flash_info *info;
3453 	struct device *dev = nor->dev;
3454 	struct mtd_info *mtd = &nor->mtd;
3455 	int ret;
3456 	int i;
3457 
3458 	ret = spi_nor_check(nor);
3459 	if (ret)
3460 		return ret;
3461 
3462 	/* Reset SPI protocol for all commands. */
3463 	nor->reg_proto = SNOR_PROTO_1_1_1;
3464 	nor->read_proto = SNOR_PROTO_1_1_1;
3465 	nor->write_proto = SNOR_PROTO_1_1_1;
3466 
3467 	/*
3468 	 * We need the bounce buffer early to read/write registers when going
3469 	 * through the spi-mem layer (buffers have to be DMA-able).
3470 	 * For spi-mem drivers, we'll reallocate a new buffer if
3471 	 * nor->params->page_size turns out to be greater than PAGE_SIZE (which
3472 	 * shouldn't happen before long since NOR pages are usually less
3473 	 * than 1KB) after spi_nor_scan() returns.
3474 	 */
3475 	nor->bouncebuf_size = PAGE_SIZE;
3476 	nor->bouncebuf = devm_kmalloc(dev, nor->bouncebuf_size,
3477 				      GFP_KERNEL);
3478 	if (!nor->bouncebuf)
3479 		return -ENOMEM;
3480 
3481 	ret = spi_nor_hw_reset(nor);
3482 	if (ret)
3483 		return ret;
3484 
3485 	info = spi_nor_get_flash_info(nor, name);
3486 	if (IS_ERR(info))
3487 		return PTR_ERR(info);
3488 
3489 	nor->info = info;
3490 
3491 	mutex_init(&nor->lock);
3492 
3493 	/* Init flash parameters based on flash_info struct and SFDP */
3494 	ret = spi_nor_init_params(nor);
3495 	if (ret)
3496 		return ret;
3497 
3498 	if (spi_nor_use_parallel_locking(nor))
3499 		init_waitqueue_head(&nor->rww.wait);
3500 
3501 	/*
3502 	 * Configure the SPI memory:
3503 	 * - select op codes for (Fast) Read, Page Program and Sector Erase.
3504 	 * - set the number of dummy cycles (mode cycles + wait states).
3505 	 * - set the SPI protocols for register and memory accesses.
3506 	 * - set the number of address bytes.
3507 	 */
3508 	ret = spi_nor_setup(nor, hwcaps);
3509 	if (ret)
3510 		return ret;
3511 
3512 	/* Send all the required SPI flash commands to initialize device */
3513 	ret = spi_nor_init(nor);
3514 	if (ret)
3515 		return ret;
3516 
3517 	/* No mtd_info fields should be used up to this point. */
3518 	spi_nor_set_mtd_info(nor);
3519 
3520 	dev_info(dev, "%s (%lld Kbytes)\n", info->name,
3521 			(long long)mtd->size >> 10);
3522 
3523 	dev_dbg(dev,
3524 		"mtd .name = %s, .size = 0x%llx (%lldMiB), "
3525 		".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n",
3526 		mtd->name, (long long)mtd->size, (long long)(mtd->size >> 20),
3527 		mtd->erasesize, mtd->erasesize / 1024, mtd->numeraseregions);
3528 
3529 	if (mtd->numeraseregions)
3530 		for (i = 0; i < mtd->numeraseregions; i++)
3531 			dev_dbg(dev,
3532 				"mtd.eraseregions[%d] = { .offset = 0x%llx, "
3533 				".erasesize = 0x%.8x (%uKiB), "
3534 				".numblocks = %d }\n",
3535 				i, (long long)mtd->eraseregions[i].offset,
3536 				mtd->eraseregions[i].erasesize,
3537 				mtd->eraseregions[i].erasesize / 1024,
3538 				mtd->eraseregions[i].numblocks);
3539 	return 0;
3540 }
3541 EXPORT_SYMBOL_GPL(spi_nor_scan);
3542 
3543 static int spi_nor_create_read_dirmap(struct spi_nor *nor)
3544 {
3545 	struct spi_mem_dirmap_info info = {
3546 		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
3547 				      SPI_MEM_OP_ADDR(nor->addr_nbytes, 0, 0),
3548 				      SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
3549 				      SPI_MEM_OP_DATA_IN(0, NULL, 0)),
3550 		.offset = 0,
3551 		.length = nor->params->size,
3552 	};
3553 	struct spi_mem_op *op = &info.op_tmpl;
3554 
3555 	spi_nor_spimem_setup_op(nor, op, nor->read_proto);
3556 
3557 	/* convert the dummy cycles to the number of bytes */
3558 	op->dummy.nbytes = (nor->read_dummy * op->dummy.buswidth) / 8;
3559 	if (spi_nor_protocol_is_dtr(nor->read_proto))
3560 		op->dummy.nbytes *= 2;
3561 
3562 	/*
3563 	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3564 	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3565 	 * do it explicitly.
3566 	 */
3567 	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
3568 
3569 	nor->dirmap.rdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3570 						       &info);
3571 	return PTR_ERR_OR_ZERO(nor->dirmap.rdesc);
3572 }
3573 
3574 static int spi_nor_create_write_dirmap(struct spi_nor *nor)
3575 {
3576 	struct spi_mem_dirmap_info info = {
3577 		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
3578 				      SPI_MEM_OP_ADDR(nor->addr_nbytes, 0, 0),
3579 				      SPI_MEM_OP_NO_DUMMY,
3580 				      SPI_MEM_OP_DATA_OUT(0, NULL, 0)),
3581 		.offset = 0,
3582 		.length = nor->params->size,
3583 	};
3584 	struct spi_mem_op *op = &info.op_tmpl;
3585 
3586 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
3587 		op->addr.nbytes = 0;
3588 
3589 	spi_nor_spimem_setup_op(nor, op, nor->write_proto);
3590 
3591 	/*
3592 	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3593 	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3594 	 * do it explicitly.
3595 	 */
3596 	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
3597 
3598 	nor->dirmap.wdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3599 						       &info);
3600 	return PTR_ERR_OR_ZERO(nor->dirmap.wdesc);
3601 }
3602 
3603 static int spi_nor_probe(struct spi_mem *spimem)
3604 {
3605 	struct spi_device *spi = spimem->spi;
3606 	struct flash_platform_data *data = dev_get_platdata(&spi->dev);
3607 	struct spi_nor *nor;
3608 	/*
3609 	 * Enable all caps by default. The core will mask them after
3610 	 * checking what's really supported using spi_mem_supports_op().
3611 	 */
3612 	const struct spi_nor_hwcaps hwcaps = { .mask = SNOR_HWCAPS_ALL };
3613 	char *flash_name;
3614 	int ret;
3615 
3616 	nor = devm_kzalloc(&spi->dev, sizeof(*nor), GFP_KERNEL);
3617 	if (!nor)
3618 		return -ENOMEM;
3619 
3620 	nor->spimem = spimem;
3621 	nor->dev = &spi->dev;
3622 	spi_nor_set_flash_node(nor, spi->dev.of_node);
3623 
3624 	spi_mem_set_drvdata(spimem, nor);
3625 
3626 	if (data && data->name)
3627 		nor->mtd.name = data->name;
3628 
3629 	if (!nor->mtd.name)
3630 		nor->mtd.name = spi_mem_get_name(spimem);
3631 
3632 	/*
3633 	 * For some (historical?) reason many platforms provide two different
3634 	 * names in flash_platform_data: "name" and "type". Quite often name is
3635 	 * set to "m25p80" and then "type" provides a real chip name.
3636 	 * If that's the case, respect "type" and ignore a "name".
3637 	 */
3638 	if (data && data->type)
3639 		flash_name = data->type;
3640 	else if (!strcmp(spi->modalias, "spi-nor"))
3641 		flash_name = NULL; /* auto-detect */
3642 	else
3643 		flash_name = spi->modalias;
3644 
3645 	ret = spi_nor_scan(nor, flash_name, &hwcaps);
3646 	if (ret)
3647 		return ret;
3648 
3649 	spi_nor_debugfs_register(nor);
3650 
3651 	/*
3652 	 * None of the existing parts have > 512B pages, but let's play safe
3653 	 * and add this logic so that if anyone ever adds support for such
3654 	 * a NOR we don't end up with buffer overflows.
3655 	 */
3656 	if (nor->params->page_size > PAGE_SIZE) {
3657 		nor->bouncebuf_size = nor->params->page_size;
3658 		devm_kfree(nor->dev, nor->bouncebuf);
3659 		nor->bouncebuf = devm_kmalloc(nor->dev,
3660 					      nor->bouncebuf_size,
3661 					      GFP_KERNEL);
3662 		if (!nor->bouncebuf)
3663 			return -ENOMEM;
3664 	}
3665 
3666 	ret = spi_nor_create_read_dirmap(nor);
3667 	if (ret)
3668 		return ret;
3669 
3670 	ret = spi_nor_create_write_dirmap(nor);
3671 	if (ret)
3672 		return ret;
3673 
3674 	return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
3675 				   data ? data->nr_parts : 0);
3676 }
3677 
3678 static int spi_nor_remove(struct spi_mem *spimem)
3679 {
3680 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3681 
3682 	spi_nor_restore(nor);
3683 
3684 	/* Clean up MTD stuff. */
3685 	return mtd_device_unregister(&nor->mtd);
3686 }
3687 
3688 static void spi_nor_shutdown(struct spi_mem *spimem)
3689 {
3690 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3691 
3692 	spi_nor_restore(nor);
3693 }
3694 
3695 /*
3696  * Do NOT add to this array without reading the following:
3697  *
3698  * Historically, many flash devices are bound to this driver by their name. But
3699  * since most of these flash are compatible to some extent, and their
3700  * differences can often be differentiated by the JEDEC read-ID command, we
3701  * encourage new users to add support to the spi-nor library, and simply bind
3702  * against a generic string here (e.g., "jedec,spi-nor").
3703  *
3704  * Many flash names are kept here in this list to keep them available
3705  * as module aliases for existing platforms.
3706  */
3707 static const struct spi_device_id spi_nor_dev_ids[] = {
3708 	/*
3709 	 * Allow non-DT platform devices to bind to the "spi-nor" modalias, and
3710 	 * hack around the fact that the SPI core does not provide uevent
3711 	 * matching for .of_match_table
3712 	 */
3713 	{"spi-nor"},
3714 
3715 	/*
3716 	 * Entries not used in DTs that should be safe to drop after replacing
3717 	 * them with "spi-nor" in platform data.
3718 	 */
3719 	{"s25sl064a"},	{"w25x16"},	{"m25p10"},	{"m25px64"},
3720 
3721 	/*
3722 	 * Entries that were used in DTs without "jedec,spi-nor" fallback and
3723 	 * should be kept for backward compatibility.
3724 	 */
3725 	{"at25df321a"},	{"at25df641"},	{"at26df081a"},
3726 	{"mx25l4005a"},	{"mx25l1606e"},	{"mx25l6405d"},	{"mx25l12805d"},
3727 	{"mx25l25635e"},{"mx66l51235l"},
3728 	{"n25q064"},	{"n25q128a11"},	{"n25q128a13"},	{"n25q512a"},
3729 	{"s25fl256s1"},	{"s25fl512s"},	{"s25sl12801"},	{"s25fl008k"},
3730 	{"s25fl064k"},
3731 	{"sst25vf040b"},{"sst25vf016b"},{"sst25vf032b"},{"sst25wf040"},
3732 	{"m25p40"},	{"m25p80"},	{"m25p16"},	{"m25p32"},
3733 	{"m25p64"},	{"m25p128"},
3734 	{"w25x80"},	{"w25x32"},	{"w25q32"},	{"w25q32dw"},
3735 	{"w25q80bl"},	{"w25q128"},	{"w25q256"},
3736 
3737 	/* Flashes that can't be detected using JEDEC */
3738 	{"m25p05-nonjedec"},	{"m25p10-nonjedec"},	{"m25p20-nonjedec"},
3739 	{"m25p40-nonjedec"},	{"m25p80-nonjedec"},	{"m25p16-nonjedec"},
3740 	{"m25p32-nonjedec"},	{"m25p64-nonjedec"},	{"m25p128-nonjedec"},
3741 
3742 	/* Everspin MRAMs (non-JEDEC) */
3743 	{ "mr25h128" }, /* 128 Kib, 40 MHz */
3744 	{ "mr25h256" }, /* 256 Kib, 40 MHz */
3745 	{ "mr25h10" },  /*   1 Mib, 40 MHz */
3746 	{ "mr25h40" },  /*   4 Mib, 40 MHz */
3747 
3748 	{ },
3749 };
3750 MODULE_DEVICE_TABLE(spi, spi_nor_dev_ids);
3751 
3752 static const struct of_device_id spi_nor_of_table[] = {
3753 	/*
3754 	 * Generic compatibility for SPI NOR that can be identified by the
3755 	 * JEDEC READ ID opcode (0x9F). Use this, if possible.
3756 	 */
3757 	{ .compatible = "jedec,spi-nor" },
3758 	{ /* sentinel */ },
3759 };
3760 MODULE_DEVICE_TABLE(of, spi_nor_of_table);
3761 
3762 /*
3763  * REVISIT: many of these chips have deep power-down modes, which
3764  * should clearly be entered on suspend() to minimize power use.
3765  * And also when they're otherwise idle...
3766  */
3767 static struct spi_mem_driver spi_nor_driver = {
3768 	.spidrv = {
3769 		.driver = {
3770 			.name = "spi-nor",
3771 			.of_match_table = spi_nor_of_table,
3772 			.dev_groups = spi_nor_sysfs_groups,
3773 		},
3774 		.id_table = spi_nor_dev_ids,
3775 	},
3776 	.probe = spi_nor_probe,
3777 	.remove = spi_nor_remove,
3778 	.shutdown = spi_nor_shutdown,
3779 };
3780 
3781 static int __init spi_nor_module_init(void)
3782 {
3783 	return spi_mem_driver_register(&spi_nor_driver);
3784 }
3785 module_init(spi_nor_module_init);
3786 
3787 static void __exit spi_nor_module_exit(void)
3788 {
3789 	spi_mem_driver_unregister(&spi_nor_driver);
3790 	spi_nor_debugfs_shutdown();
3791 }
3792 module_exit(spi_nor_module_exit);
3793 
3794 MODULE_LICENSE("GPL v2");
3795 MODULE_AUTHOR("Huang Shijie <shijie8@gmail.com>");
3796 MODULE_AUTHOR("Mike Lavender");
3797 MODULE_DESCRIPTION("framework for SPI NOR");
3798