1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * linux/drivers/mmc/core/sdio_io.c
4 *
5 * Copyright 2007-2008 Pierre Ossman
6 */
7
8 #include <linux/export.h>
9 #include <linux/kernel.h>
10 #include <linux/mmc/host.h>
11 #include <linux/mmc/card.h>
12 #include <linux/mmc/sdio.h>
13 #include <linux/mmc/sdio_func.h>
14
15 #include "sdio_ops.h"
16 #include "core.h"
17 #include "card.h"
18 #include "host.h"
19
20 /**
21 * sdio_claim_host - exclusively claim a bus for a certain SDIO function
22 * @func: SDIO function that will be accessed
23 *
24 * Claim a bus for a set of operations. The SDIO function given
25 * is used to figure out which bus is relevant.
26 */
27 void sdio_claim_host(struct sdio_func *func)
28 {
29 if (WARN_ON(!func))
30 return;
31
32 mmc_claim_host(func->card->host);
33 }
34 EXPORT_SYMBOL_GPL(sdio_claim_host);
35
36 /**
37 * sdio_release_host - release a bus for a certain SDIO function
38 * @func: SDIO function that was accessed
39 *
40 * Release a bus, allowing others to claim the bus for their
41 * operations.
42 */
43 void sdio_release_host(struct sdio_func *func)
44 {
45 if (WARN_ON(!func))
46 return;
47
48 mmc_release_host(func->card->host);
49 }
50 EXPORT_SYMBOL_GPL(sdio_release_host);
51
52 /**
53 * sdio_enable_func - enables a SDIO function for usage
54 * @func: SDIO function to enable
55 *
56 * Powers up and activates a SDIO function so that register
57 * access is possible.
58 */
59 int sdio_enable_func(struct sdio_func *func)
60 {
61 int ret;
62 unsigned char reg;
63 unsigned long timeout;
64
65 if (!func)
66 return -EINVAL;
67
68 pr_debug("SDIO: Enabling device %s...\n", sdio_func_id(func));
69
70 ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IOEx, 0, ®);
71 if (ret)
72 goto err;
73
74 reg |= 1 << func->num;
75
76 ret = mmc_io_rw_direct(func->card, 1, 0, SDIO_CCCR_IOEx, reg, NULL);
77 if (ret)
78 goto err;
79
80 timeout = jiffies + msecs_to_jiffies(func->enable_timeout);
81
82 while (1) {
83 ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IORx, 0, ®);
84 if (ret)
85 goto err;
86 if (reg & (1 << func->num))
87 break;
88 ret = -ETIME;
89 if (time_after(jiffies, timeout))
90 goto err;
91 }
92
93 pr_debug("SDIO: Enabled device %s\n", sdio_func_id(func));
94
95 return 0;
96
97 err:
98 pr_debug("SDIO: Failed to enable device %s\n", sdio_func_id(func));
99 return ret;
100 }
101 EXPORT_SYMBOL_GPL(sdio_enable_func);
102
103 /**
104 * sdio_disable_func - disable a SDIO function
105 * @func: SDIO function to disable
106 *
107 * Powers down and deactivates a SDIO function. Register access
108 * to this function will fail until the function is reenabled.
109 */
110 int sdio_disable_func(struct sdio_func *func)
111 {
112 int ret;
113 unsigned char reg;
114
115 if (!func)
116 return -EINVAL;
117
118 pr_debug("SDIO: Disabling device %s...\n", sdio_func_id(func));
119
120 ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IOEx, 0, ®);
121 if (ret)
122 goto err;
123
124 reg &= ~(1 << func->num);
125
126 ret = mmc_io_rw_direct(func->card, 1, 0, SDIO_CCCR_IOEx, reg, NULL);
127 if (ret)
128 goto err;
129
130 pr_debug("SDIO: Disabled device %s\n", sdio_func_id(func));
131
132 return 0;
133
134 err:
135 pr_debug("SDIO: Failed to disable device %s\n", sdio_func_id(func));
136 return -EIO;
137 }
138 EXPORT_SYMBOL_GPL(sdio_disable_func);
139
140 /**
141 * sdio_set_block_size - set the block size of an SDIO function
142 * @func: SDIO function to change
143 * @blksz: new block size or 0 to use the default.
144 *
145 * The default block size is the largest supported by both the function
146 * and the host, with a maximum of 512 to ensure that arbitrarily sized
147 * data transfer use the optimal (least) number of commands.
148 *
149 * A driver may call this to override the default block size set by the
150 * core. This can be used to set a block size greater than the maximum
151 * that reported by the card; it is the driver's responsibility to ensure
152 * it uses a value that the card supports.
153 *
154 * Returns 0 on success, -EINVAL if the host does not support the
155 * requested block size, or -EIO (etc.) if one of the resultant FBR block
156 * size register writes failed.
157 *
158 */
159 int sdio_set_block_size(struct sdio_func *func, unsigned blksz)
160 {
161 int ret;
162
163 if (blksz > func->card->host->max_blk_size)
164 return -EINVAL;
165
166 if (blksz == 0) {
167 blksz = min(func->max_blksize, func->card->host->max_blk_size);
168 blksz = min(blksz, 512u);
169 }
170
171 ret = mmc_io_rw_direct(func->card, 1, 0,
172 SDIO_FBR_BASE(func->num) + SDIO_FBR_BLKSIZE,
173 blksz & 0xff, NULL);
174 if (ret)
175 return ret;
176 ret = mmc_io_rw_direct(func->card, 1, 0,
177 SDIO_FBR_BASE(func->num) + SDIO_FBR_BLKSIZE + 1,
178 (blksz >> 8) & 0xff, NULL);
179 if (ret)
180 return ret;
181 func->cur_blksize = blksz;
182 return 0;
183 }
184 EXPORT_SYMBOL_GPL(sdio_set_block_size);
185
186 /*
187 * Calculate the maximum byte mode transfer size
188 */
189 static inline unsigned int sdio_max_byte_size(struct sdio_func *func)
190 {
191 unsigned mval = func->card->host->max_blk_size;
192
193 if (mmc_blksz_for_byte_mode(func->card))
194 mval = min(mval, func->cur_blksize);
195 else
196 mval = min(mval, func->max_blksize);
197
198 if (mmc_card_broken_byte_mode_512(func->card))
199 return min(mval, 511u);
200
201 return min(mval, 512u); /* maximum size for byte mode */
202 }
203
204 /*
205 * This is legacy code, which needs to be re-worked some day. Basically we need
206 * to take into account the properties of the host, as to enable the SDIO func
207 * driver layer to allocate optimal buffers.
208 */
209 static inline unsigned int _sdio_align_size(unsigned int sz)
210 {
211 /*
212 * FIXME: We don't have a system for the controller to tell
213 * the core about its problems yet, so for now we just 32-bit
214 * align the size.
215 */
216 return ALIGN(sz, 4);
217 }
218
219 /**
220 * sdio_align_size - pads a transfer size to a more optimal value
221 * @func: SDIO function
222 * @sz: original transfer size
223 *
224 * Pads the original data size with a number of extra bytes in
225 * order to avoid controller bugs and/or performance hits
226 * (e.g. some controllers revert to PIO for certain sizes).
227 *
228 * If possible, it will also adjust the size so that it can be
229 * handled in just a single request.
230 *
231 * Returns the improved size, which might be unmodified.
232 */
233 unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz)
234 {
235 unsigned int orig_sz;
236 unsigned int blk_sz, byte_sz;
237 unsigned chunk_sz;
238
239 orig_sz = sz;
240
241 /*
242 * Do a first check with the controller, in case it
243 * wants to increase the size up to a point where it
244 * might need more than one block.
245 */
246 sz = _sdio_align_size(sz);
247
248 /*
249 * If we can still do this with just a byte transfer, then
250 * we're done.
251 */
252 if (sz <= sdio_max_byte_size(func))
253 return sz;
254
255 if (func->card->cccr.multi_block) {
256 /*
257 * Check if the transfer is already block aligned
258 */
259 if ((sz % func->cur_blksize) == 0)
260 return sz;
261
262 /*
263 * Realign it so that it can be done with one request,
264 * and recheck if the controller still likes it.
265 */
266 blk_sz = ((sz + func->cur_blksize - 1) /
267 func->cur_blksize) * func->cur_blksize;
268 blk_sz = _sdio_align_size(blk_sz);
269
270 /*
271 * This value is only good if it is still just
272 * one request.
273 */
274 if ((blk_sz % func->cur_blksize) == 0)
275 return blk_sz;
276
277 /*
278 * We failed to do one request, but at least try to
279 * pad the remainder properly.
280 */
281 byte_sz = _sdio_align_size(sz % func->cur_blksize);
282 if (byte_sz <= sdio_max_byte_size(func)) {
283 blk_sz = sz / func->cur_blksize;
284 return blk_sz * func->cur_blksize + byte_sz;
285 }
286 } else {
287 /*
288 * We need multiple requests, so first check that the
289 * controller can handle the chunk size;
290 */
291 chunk_sz = _sdio_align_size(sdio_max_byte_size(func));
292 if (chunk_sz == sdio_max_byte_size(func)) {
293 /*
294 * Fix up the size of the remainder (if any)
295 */
296 byte_sz = orig_sz % chunk_sz;
297 if (byte_sz) {
298 byte_sz = _sdio_align_size(byte_sz);
299 }
300
301 return (orig_sz / chunk_sz) * chunk_sz + byte_sz;
302 }
303 }
304
305 /*
306 * The controller is simply incapable of transferring the size
307 * we want in decent manner, so just return the original size.
308 */
309 return orig_sz;
310 }
311 EXPORT_SYMBOL_GPL(sdio_align_size);
312
313 /* Split an arbitrarily sized data transfer into several
314 * IO_RW_EXTENDED commands. */
315 static int sdio_io_rw_ext_helper(struct sdio_func *func, int write,
316 unsigned addr, int incr_addr, u8 *buf, unsigned size)
317 {
318 unsigned remainder = size;
319 unsigned max_blocks;
320 int ret;
321
322 if (!func || (func->num > 7))
323 return -EINVAL;
324
325 /* Do the bulk of the transfer using block mode (if supported). */
326 if (func->card->cccr.multi_block && (size > sdio_max_byte_size(func))) {
327 /* Blocks per command is limited by host count, host transfer
328 * size and the maximum for IO_RW_EXTENDED of 511 blocks. */
329 max_blocks = min(func->card->host->max_blk_count, 511u);
330
331 while (remainder >= func->cur_blksize) {
332 unsigned blocks;
333
334 blocks = remainder / func->cur_blksize;
335 if (blocks > max_blocks)
336 blocks = max_blocks;
337 size = blocks * func->cur_blksize;
338
339 ret = mmc_io_rw_extended(func->card, write,
340 func->num, addr, incr_addr, buf,
341 blocks, func->cur_blksize);
342 if (ret)
343 return ret;
344
345 remainder -= size;
346 buf += size;
347 if (incr_addr)
348 addr += size;
349 }
350 }
351
352 /* Write the remainder using byte mode. */
353 while (remainder > 0) {
354 size = min(remainder, sdio_max_byte_size(func));
355
356 /* Indicate byte mode by setting "blocks" = 0 */
357 ret = mmc_io_rw_extended(func->card, write, func->num, addr,
358 incr_addr, buf, 0, size);
359 if (ret)
360 return ret;
361
362 remainder -= size;
363 buf += size;
364 if (incr_addr)
365 addr += size;
366 }
367 return 0;
368 }
369
370 /**
371 * sdio_readb - read a single byte from a SDIO function
372 * @func: SDIO function to access
373 * @addr: address to read
374 * @err_ret: optional status value from transfer
375 *
376 * Reads a single byte from the address space of a given SDIO
377 * function. If there is a problem reading the address, 0xff
378 * is returned and @err_ret will contain the error code.
379 */
380 u8 sdio_readb(struct sdio_func *func, unsigned int addr, int *err_ret)
381 {
382 int ret;
383 u8 val;
384
385 if (!func) {
386 if (err_ret)
387 *err_ret = -EINVAL;
388 return 0xFF;
389 }
390
391 ret = mmc_io_rw_direct(func->card, 0, func->num, addr, 0, &val);
392 if (err_ret)
393 *err_ret = ret;
394 if (ret)
395 return 0xFF;
396
397 return val;
398 }
399 EXPORT_SYMBOL_GPL(sdio_readb);
400
401 /**
402 * sdio_writeb - write a single byte to a SDIO function
403 * @func: SDIO function to access
404 * @b: byte to write
405 * @addr: address to write to
406 * @err_ret: optional status value from transfer
407 *
408 * Writes a single byte to the address space of a given SDIO
409 * function. @err_ret will contain the status of the actual
410 * transfer.
411 */
412 void sdio_writeb(struct sdio_func *func, u8 b, unsigned int addr, int *err_ret)
413 {
414 int ret;
415
416 if (!func) {
417 if (err_ret)
418 *err_ret = -EINVAL;
419 return;
420 }
421
422 ret = mmc_io_rw_direct(func->card, 1, func->num, addr, b, NULL);
423 if (err_ret)
424 *err_ret = ret;
425 }
426 EXPORT_SYMBOL_GPL(sdio_writeb);
427
428 /**
429 * sdio_writeb_readb - write and read a byte from SDIO function
430 * @func: SDIO function to access
431 * @write_byte: byte to write
432 * @addr: address to write to
433 * @err_ret: optional status value from transfer
434 *
435 * Performs a RAW (Read after Write) operation as defined by SDIO spec -
436 * single byte is written to address space of a given SDIO function and
437 * response is read back from the same address, both using single request.
438 * If there is a problem with the operation, 0xff is returned and
439 * @err_ret will contain the error code.
440 */
441 u8 sdio_writeb_readb(struct sdio_func *func, u8 write_byte,
442 unsigned int addr, int *err_ret)
443 {
444 int ret;
445 u8 val;
446
447 ret = mmc_io_rw_direct(func->card, 1, func->num, addr,
448 write_byte, &val);
449 if (err_ret)
450 *err_ret = ret;
451 if (ret)
452 return 0xff;
453
454 return val;
455 }
456 EXPORT_SYMBOL_GPL(sdio_writeb_readb);
457
458 /**
459 * sdio_memcpy_fromio - read a chunk of memory from a SDIO function
460 * @func: SDIO function to access
461 * @dst: buffer to store the data
462 * @addr: address to begin reading from
463 * @count: number of bytes to read
464 *
465 * Reads from the address space of a given SDIO function. Return
466 * value indicates if the transfer succeeded or not.
467 */
468 int sdio_memcpy_fromio(struct sdio_func *func, void *dst,
469 unsigned int addr, int count)
470 {
471 return sdio_io_rw_ext_helper(func, 0, addr, 1, dst, count);
472 }
473 EXPORT_SYMBOL_GPL(sdio_memcpy_fromio);
474
475 /**
476 * sdio_memcpy_toio - write a chunk of memory to a SDIO function
477 * @func: SDIO function to access
478 * @addr: address to start writing to
479 * @src: buffer that contains the data to write
480 * @count: number of bytes to write
481 *
482 * Writes to the address space of a given SDIO function. Return
483 * value indicates if the transfer succeeded or not.
484 */
485 int sdio_memcpy_toio(struct sdio_func *func, unsigned int addr,
486 void *src, int count)
487 {
488 return sdio_io_rw_ext_helper(func, 1, addr, 1, src, count);
489 }
490 EXPORT_SYMBOL_GPL(sdio_memcpy_toio);
491
492 /**
493 * sdio_readsb - read from a FIFO on a SDIO function
494 * @func: SDIO function to access
495 * @dst: buffer to store the data
496 * @addr: address of (single byte) FIFO
497 * @count: number of bytes to read
498 *
499 * Reads from the specified FIFO of a given SDIO function. Return
500 * value indicates if the transfer succeeded or not.
501 */
502 int sdio_readsb(struct sdio_func *func, void *dst, unsigned int addr,
503 int count)
504 {
505 return sdio_io_rw_ext_helper(func, 0, addr, 0, dst, count);
506 }
507 EXPORT_SYMBOL_GPL(sdio_readsb);
508
509 /**
510 * sdio_writesb - write to a FIFO of a SDIO function
511 * @func: SDIO function to access
512 * @addr: address of (single byte) FIFO
513 * @src: buffer that contains the data to write
514 * @count: number of bytes to write
515 *
516 * Writes to the specified FIFO of a given SDIO function. Return
517 * value indicates if the transfer succeeded or not.
518 */
519 int sdio_writesb(struct sdio_func *func, unsigned int addr, void *src,
520 int count)
521 {
522 return sdio_io_rw_ext_helper(func, 1, addr, 0, src, count);
523 }
524 EXPORT_SYMBOL_GPL(sdio_writesb);
525
526 /**
527 * sdio_readw - read a 16 bit integer from a SDIO function
528 * @func: SDIO function to access
529 * @addr: address to read
530 * @err_ret: optional status value from transfer
531 *
532 * Reads a 16 bit integer from the address space of a given SDIO
533 * function. If there is a problem reading the address, 0xffff
534 * is returned and @err_ret will contain the error code.
535 */
536 u16 sdio_readw(struct sdio_func *func, unsigned int addr, int *err_ret)
537 {
538 int ret;
539
540 ret = sdio_memcpy_fromio(func, func->tmpbuf, addr, 2);
541 if (err_ret)
542 *err_ret = ret;
543 if (ret)
544 return 0xFFFF;
545
546 return le16_to_cpup((__le16 *)func->tmpbuf);
547 }
548 EXPORT_SYMBOL_GPL(sdio_readw);
549
550 /**
551 * sdio_writew - write a 16 bit integer to a SDIO function
552 * @func: SDIO function to access
553 * @b: integer to write
554 * @addr: address to write to
555 * @err_ret: optional status value from transfer
556 *
557 * Writes a 16 bit integer to the address space of a given SDIO
558 * function. @err_ret will contain the status of the actual
559 * transfer.
560 */
561 void sdio_writew(struct sdio_func *func, u16 b, unsigned int addr, int *err_ret)
562 {
563 int ret;
564
565 *(__le16 *)func->tmpbuf = cpu_to_le16(b);
566
567 ret = sdio_memcpy_toio(func, addr, func->tmpbuf, 2);
568 if (err_ret)
569 *err_ret = ret;
570 }
571 EXPORT_SYMBOL_GPL(sdio_writew);
572
573 /**
574 * sdio_readl - read a 32 bit integer from a SDIO function
575 * @func: SDIO function to access
576 * @addr: address to read
577 * @err_ret: optional status value from transfer
578 *
579 * Reads a 32 bit integer from the address space of a given SDIO
580 * function. If there is a problem reading the address,
581 * 0xffffffff is returned and @err_ret will contain the error
582 * code.
583 */
584 u32 sdio_readl(struct sdio_func *func, unsigned int addr, int *err_ret)
585 {
586 int ret;
587
588 ret = sdio_memcpy_fromio(func, func->tmpbuf, addr, 4);
589 if (err_ret)
590 *err_ret = ret;
591 if (ret)
592 return 0xFFFFFFFF;
593
594 return le32_to_cpup((__le32 *)func->tmpbuf);
595 }
596 EXPORT_SYMBOL_GPL(sdio_readl);
597
598 /**
599 * sdio_writel - write a 32 bit integer to a SDIO function
600 * @func: SDIO function to access
601 * @b: integer to write
602 * @addr: address to write to
603 * @err_ret: optional status value from transfer
604 *
605 * Writes a 32 bit integer to the address space of a given SDIO
606 * function. @err_ret will contain the status of the actual
607 * transfer.
608 */
609 void sdio_writel(struct sdio_func *func, u32 b, unsigned int addr, int *err_ret)
610 {
611 int ret;
612
613 *(__le32 *)func->tmpbuf = cpu_to_le32(b);
614
615 ret = sdio_memcpy_toio(func, addr, func->tmpbuf, 4);
616 if (err_ret)
617 *err_ret = ret;
618 }
619 EXPORT_SYMBOL_GPL(sdio_writel);
620
621 /**
622 * sdio_f0_readb - read a single byte from SDIO function 0
623 * @func: an SDIO function of the card
624 * @addr: address to read
625 * @err_ret: optional status value from transfer
626 *
627 * Reads a single byte from the address space of SDIO function 0.
628 * If there is a problem reading the address, 0xff is returned
629 * and @err_ret will contain the error code.
630 */
631 unsigned char sdio_f0_readb(struct sdio_func *func, unsigned int addr,
632 int *err_ret)
633 {
634 int ret;
635 unsigned char val;
636
637 if (!func) {
638 if (err_ret)
639 *err_ret = -EINVAL;
640 return 0xFF;
641 }
642
643 ret = mmc_io_rw_direct(func->card, 0, 0, addr, 0, &val);
644 if (err_ret)
645 *err_ret = ret;
646 if (ret)
647 return 0xFF;
648
649 return val;
650 }
651 EXPORT_SYMBOL_GPL(sdio_f0_readb);
652
653 /**
654 * sdio_f0_writeb - write a single byte to SDIO function 0
655 * @func: an SDIO function of the card
656 * @b: byte to write
657 * @addr: address to write to
658 * @err_ret: optional status value from transfer
659 *
660 * Writes a single byte to the address space of SDIO function 0.
661 * @err_ret will contain the status of the actual transfer.
662 *
663 * Only writes to the vendor specific CCCR registers (0xF0 -
664 * 0xFF) are permiited; @err_ret will be set to -EINVAL for *
665 * writes outside this range.
666 */
667 void sdio_f0_writeb(struct sdio_func *func, unsigned char b, unsigned int addr,
668 int *err_ret)
669 {
670 int ret;
671
672 if (!func) {
673 if (err_ret)
674 *err_ret = -EINVAL;
675 return;
676 }
677
678 if ((addr < 0xF0 || addr > 0xFF) && (!mmc_card_lenient_fn0(func->card))) {
679 if (err_ret)
680 *err_ret = -EINVAL;
681 return;
682 }
683
684 ret = mmc_io_rw_direct(func->card, 1, 0, addr, b, NULL);
685 if (err_ret)
686 *err_ret = ret;
687 }
688 EXPORT_SYMBOL_GPL(sdio_f0_writeb);
689
690 /**
691 * sdio_get_host_pm_caps - get host power management capabilities
692 * @func: SDIO function attached to host
693 *
694 * Returns a capability bitmask corresponding to power management
695 * features supported by the host controller that the card function
696 * might rely upon during a system suspend. The host doesn't need
697 * to be claimed, nor the function active, for this information to be
698 * obtained.
699 */
700 mmc_pm_flag_t sdio_get_host_pm_caps(struct sdio_func *func)
701 {
702 if (!func)
703 return 0;
704
705 return func->card->host->pm_caps;
706 }
707 EXPORT_SYMBOL_GPL(sdio_get_host_pm_caps);
708
709 /**
710 * sdio_set_host_pm_flags - set wanted host power management capabilities
711 * @func: SDIO function attached to host
712 *
713 * Set a capability bitmask corresponding to wanted host controller
714 * power management features for the upcoming suspend state.
715 * This must be called, if needed, each time the suspend method of
716 * the function driver is called, and must contain only bits that
717 * were returned by sdio_get_host_pm_caps().
718 * The host doesn't need to be claimed, nor the function active,
719 * for this information to be set.
720 */
721 int sdio_set_host_pm_flags(struct sdio_func *func, mmc_pm_flag_t flags)
722 {
723 struct mmc_host *host;
724
725 if (!func)
726 return -EINVAL;
727
728 host = func->card->host;
729
730 if (flags & ~host->pm_caps)
731 return -EINVAL;
732
733 /* function suspend methods are serialized, hence no lock needed */
734 host->pm_flags |= flags;
735 return 0;
736 }
737 EXPORT_SYMBOL_GPL(sdio_set_host_pm_flags);
738
739 /**
740 * sdio_retune_crc_disable - temporarily disable retuning on CRC errors
741 * @func: SDIO function attached to host
742 *
743 * If the SDIO card is known to be in a state where it might produce
744 * CRC errors on the bus in response to commands (like if we know it is
745 * transitioning between power states), an SDIO function driver can
746 * call this function to temporarily disable the SD/MMC core behavior of
747 * triggering an automatic retuning.
748 *
749 * This function should be called while the host is claimed and the host
750 * should remain claimed until sdio_retune_crc_enable() is called.
751 * Specifically, the expected sequence of calls is:
752 * - sdio_claim_host()
753 * - sdio_retune_crc_disable()
754 * - some number of calls like sdio_writeb() and sdio_readb()
755 * - sdio_retune_crc_enable()
756 * - sdio_release_host()
757 */
758 void sdio_retune_crc_disable(struct sdio_func *func)
759 {
760 func->card->host->retune_crc_disable = true;
761 }
762 EXPORT_SYMBOL_GPL(sdio_retune_crc_disable);
763
764 /**
765 * sdio_retune_crc_enable - re-enable retuning on CRC errors
766 * @func: SDIO function attached to host
767 *
768 * This is the compement to sdio_retune_crc_disable().
769 */
770 void sdio_retune_crc_enable(struct sdio_func *func)
771 {
772 func->card->host->retune_crc_disable = false;
773 }
774 EXPORT_SYMBOL_GPL(sdio_retune_crc_enable);
775
776 /**
777 * sdio_retune_hold_now - start deferring retuning requests till release
778 * @func: SDIO function attached to host
779 *
780 * This function can be called if it's currently a bad time to do
781 * a retune of the SDIO card. Retune requests made during this time
782 * will be held and we'll actually do the retune sometime after the
783 * release.
784 *
785 * This function could be useful if an SDIO card is in a power state
786 * where it can respond to a small subset of commands that doesn't
787 * include the retuning command. Care should be taken when using
788 * this function since (presumably) the retuning request we might be
789 * deferring was made for a good reason.
790 *
791 * This function should be called while the host is claimed.
792 */
793 void sdio_retune_hold_now(struct sdio_func *func)
794 {
795 mmc_retune_hold_now(func->card->host);
796 }
797 EXPORT_SYMBOL_GPL(sdio_retune_hold_now);
798
799 /**
800 * sdio_retune_release - signal that it's OK to retune now
801 * @func: SDIO function attached to host
802 *
803 * This is the complement to sdio_retune_hold_now(). Calling this
804 * function won't make a retune happen right away but will allow
805 * them to be scheduled normally.
806 *
807 * This function should be called while the host is claimed.
808 */
809 void sdio_retune_release(struct sdio_func *func)
810 {
811 mmc_retune_release(func->card->host);
812 }
813 EXPORT_SYMBOL_GPL(sdio_retune_release);