1 /*
2 * linux/drivers/mmc/core/sdio_io.c
3 *
4 * Copyright 2007-2008 Pierre Ossman
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or (at
9 * your option) any later version.
10 */
11
12 #include <linux/export.h>
13 #include <linux/mmc/host.h>
14 #include <linux/mmc/card.h>
15 #include <linux/mmc/sdio.h>
16 #include <linux/mmc/sdio_func.h>
17
18 #include "sdio_ops.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 */
sdio_claim_host(struct sdio_func * func)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 */
sdio_release_host(struct sdio_func * func)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 */
sdio_enable_func(struct sdio_func * func)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 */
sdio_disable_func(struct sdio_func * func)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 */
sdio_set_block_size(struct sdio_func * func,unsigned blksz)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 */
sdio_max_byte_size(struct sdio_func * func)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 * sdio_align_size - pads a transfer size to a more optimal value
206 * @func: SDIO function
207 * @sz: original transfer size
208 *
209 * Pads the original data size with a number of extra bytes in
210 * order to avoid controller bugs and/or performance hits
211 * (e.g. some controllers revert to PIO for certain sizes).
212 *
213 * If possible, it will also adjust the size so that it can be
214 * handled in just a single request.
215 *
216 * Returns the improved size, which might be unmodified.
217 */
sdio_align_size(struct sdio_func * func,unsigned int sz)218 unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz)
219 {
220 unsigned int orig_sz;
221 unsigned int blk_sz, byte_sz;
222 unsigned chunk_sz;
223
224 orig_sz = sz;
225
226 /*
227 * Do a first check with the controller, in case it
228 * wants to increase the size up to a point where it
229 * might need more than one block.
230 */
231 sz = mmc_align_data_size(func->card, sz);
232
233 /*
234 * If we can still do this with just a byte transfer, then
235 * we're done.
236 */
237 if (sz <= sdio_max_byte_size(func))
238 return sz;
239
240 if (func->card->cccr.multi_block) {
241 /*
242 * Check if the transfer is already block aligned
243 */
244 if ((sz % func->cur_blksize) == 0)
245 return sz;
246
247 /*
248 * Realign it so that it can be done with one request,
249 * and recheck if the controller still likes it.
250 */
251 blk_sz = ((sz + func->cur_blksize - 1) /
252 func->cur_blksize) * func->cur_blksize;
253 blk_sz = mmc_align_data_size(func->card, blk_sz);
254
255 /*
256 * This value is only good if it is still just
257 * one request.
258 */
259 if ((blk_sz % func->cur_blksize) == 0)
260 return blk_sz;
261
262 /*
263 * We failed to do one request, but at least try to
264 * pad the remainder properly.
265 */
266 byte_sz = mmc_align_data_size(func->card,
267 sz % func->cur_blksize);
268 if (byte_sz <= sdio_max_byte_size(func)) {
269 blk_sz = sz / func->cur_blksize;
270 return blk_sz * func->cur_blksize + byte_sz;
271 }
272 } else {
273 /*
274 * We need multiple requests, so first check that the
275 * controller can handle the chunk size;
276 */
277 chunk_sz = mmc_align_data_size(func->card,
278 sdio_max_byte_size(func));
279 if (chunk_sz == sdio_max_byte_size(func)) {
280 /*
281 * Fix up the size of the remainder (if any)
282 */
283 byte_sz = orig_sz % chunk_sz;
284 if (byte_sz) {
285 byte_sz = mmc_align_data_size(func->card,
286 byte_sz);
287 }
288
289 return (orig_sz / chunk_sz) * chunk_sz + byte_sz;
290 }
291 }
292
293 /*
294 * The controller is simply incapable of transferring the size
295 * we want in decent manner, so just return the original size.
296 */
297 return orig_sz;
298 }
299 EXPORT_SYMBOL_GPL(sdio_align_size);
300
301 /* Split an arbitrarily sized data transfer into several
302 * IO_RW_EXTENDED commands. */
sdio_io_rw_ext_helper(struct sdio_func * func,int write,unsigned addr,int incr_addr,u8 * buf,unsigned size)303 static int sdio_io_rw_ext_helper(struct sdio_func *func, int write,
304 unsigned addr, int incr_addr, u8 *buf, unsigned size)
305 {
306 unsigned remainder = size;
307 unsigned max_blocks;
308 int ret;
309
310 if (!func || (func->num > 7))
311 return -EINVAL;
312
313 /* Do the bulk of the transfer using block mode (if supported). */
314 if (func->card->cccr.multi_block && (size > sdio_max_byte_size(func))) {
315 /* Blocks per command is limited by host count, host transfer
316 * size and the maximum for IO_RW_EXTENDED of 511 blocks. */
317 max_blocks = min(func->card->host->max_blk_count, 511u);
318
319 while (remainder >= func->cur_blksize) {
320 unsigned blocks;
321
322 blocks = remainder / func->cur_blksize;
323 if (blocks > max_blocks)
324 blocks = max_blocks;
325 size = blocks * func->cur_blksize;
326
327 ret = mmc_io_rw_extended(func->card, write,
328 func->num, addr, incr_addr, buf,
329 blocks, func->cur_blksize);
330 if (ret)
331 return ret;
332
333 remainder -= size;
334 buf += size;
335 if (incr_addr)
336 addr += size;
337 }
338 }
339
340 /* Write the remainder using byte mode. */
341 while (remainder > 0) {
342 size = min(remainder, sdio_max_byte_size(func));
343
344 /* Indicate byte mode by setting "blocks" = 0 */
345 ret = mmc_io_rw_extended(func->card, write, func->num, addr,
346 incr_addr, buf, 0, size);
347 if (ret)
348 return ret;
349
350 remainder -= size;
351 buf += size;
352 if (incr_addr)
353 addr += size;
354 }
355 return 0;
356 }
357
358 /**
359 * sdio_readb - read a single byte from a SDIO function
360 * @func: SDIO function to access
361 * @addr: address to read
362 * @err_ret: optional status value from transfer
363 *
364 * Reads a single byte from the address space of a given SDIO
365 * function. If there is a problem reading the address, 0xff
366 * is returned and @err_ret will contain the error code.
367 */
sdio_readb(struct sdio_func * func,unsigned int addr,int * err_ret)368 u8 sdio_readb(struct sdio_func *func, unsigned int addr, int *err_ret)
369 {
370 int ret;
371 u8 val;
372
373 if (!func) {
374 *err_ret = -EINVAL;
375 return 0xFF;
376 }
377
378 if (err_ret)
379 *err_ret = 0;
380
381 ret = mmc_io_rw_direct(func->card, 0, func->num, addr, 0, &val);
382 if (ret) {
383 if (err_ret)
384 *err_ret = ret;
385 return 0xFF;
386 }
387
388 return val;
389 }
390 EXPORT_SYMBOL_GPL(sdio_readb);
391
392 /**
393 * sdio_readb_ext - read a single byte from a SDIO function
394 * @func: SDIO function to access
395 * @addr: address to read
396 * @err_ret: optional status value from transfer
397 * @in: value to add to argument
398 *
399 * Reads a single byte from the address space of a given SDIO
400 * function. If there is a problem reading the address, 0xff
401 * is returned and @err_ret will contain the error code.
402 */
sdio_readb_ext(struct sdio_func * func,unsigned int addr,int * err_ret,unsigned in)403 unsigned char sdio_readb_ext(struct sdio_func *func, unsigned int addr,
404 int *err_ret, unsigned in)
405 {
406 int ret;
407 unsigned char val;
408
409 BUG_ON(!func);
410
411 if (err_ret)
412 *err_ret = 0;
413
414 ret = mmc_io_rw_direct(func->card, 0, func->num, addr, (u8)in, &val);
415 if (ret) {
416 if (err_ret)
417 *err_ret = ret;
418 return 0xFF;
419 }
420
421 return val;
422 }
423 EXPORT_SYMBOL_GPL(sdio_readb_ext);
424
425 /**
426 * sdio_writeb - write a single byte to a SDIO function
427 * @func: SDIO function to access
428 * @b: byte to write
429 * @addr: address to write to
430 * @err_ret: optional status value from transfer
431 *
432 * Writes a single byte to the address space of a given SDIO
433 * function. @err_ret will contain the status of the actual
434 * transfer.
435 */
sdio_writeb(struct sdio_func * func,u8 b,unsigned int addr,int * err_ret)436 void sdio_writeb(struct sdio_func *func, u8 b, unsigned int addr, int *err_ret)
437 {
438 int ret;
439
440 if (!func) {
441 *err_ret = -EINVAL;
442 return;
443 }
444
445 ret = mmc_io_rw_direct(func->card, 1, func->num, addr, b, NULL);
446 if (err_ret)
447 *err_ret = ret;
448 }
449 EXPORT_SYMBOL_GPL(sdio_writeb);
450
451 /**
452 * sdio_writeb_readb - write and read a byte from SDIO function
453 * @func: SDIO function to access
454 * @write_byte: byte to write
455 * @addr: address to write to
456 * @err_ret: optional status value from transfer
457 *
458 * Performs a RAW (Read after Write) operation as defined by SDIO spec -
459 * single byte is written to address space of a given SDIO function and
460 * response is read back from the same address, both using single request.
461 * If there is a problem with the operation, 0xff is returned and
462 * @err_ret will contain the error code.
463 */
sdio_writeb_readb(struct sdio_func * func,u8 write_byte,unsigned int addr,int * err_ret)464 u8 sdio_writeb_readb(struct sdio_func *func, u8 write_byte,
465 unsigned int addr, int *err_ret)
466 {
467 int ret;
468 u8 val;
469
470 ret = mmc_io_rw_direct(func->card, 1, func->num, addr,
471 write_byte, &val);
472 if (err_ret)
473 *err_ret = ret;
474 if (ret)
475 val = 0xff;
476
477 return val;
478 }
479 EXPORT_SYMBOL_GPL(sdio_writeb_readb);
480
481 /**
482 * sdio_memcpy_fromio - read a chunk of memory from a SDIO function
483 * @func: SDIO function to access
484 * @dst: buffer to store the data
485 * @addr: address to begin reading from
486 * @count: number of bytes to read
487 *
488 * Reads from the address space of a given SDIO function. Return
489 * value indicates if the transfer succeeded or not.
490 */
sdio_memcpy_fromio(struct sdio_func * func,void * dst,unsigned int addr,int count)491 int sdio_memcpy_fromio(struct sdio_func *func, void *dst,
492 unsigned int addr, int count)
493 {
494 return sdio_io_rw_ext_helper(func, 0, addr, 1, dst, count);
495 }
496 EXPORT_SYMBOL_GPL(sdio_memcpy_fromio);
497
498 /**
499 * sdio_memcpy_toio - write a chunk of memory to a SDIO function
500 * @func: SDIO function to access
501 * @addr: address to start writing to
502 * @src: buffer that contains the data to write
503 * @count: number of bytes to write
504 *
505 * Writes to the address space of a given SDIO function. Return
506 * value indicates if the transfer succeeded or not.
507 */
sdio_memcpy_toio(struct sdio_func * func,unsigned int addr,void * src,int count)508 int sdio_memcpy_toio(struct sdio_func *func, unsigned int addr,
509 void *src, int count)
510 {
511 return sdio_io_rw_ext_helper(func, 1, addr, 1, src, count);
512 }
513 EXPORT_SYMBOL_GPL(sdio_memcpy_toio);
514
515 /**
516 * sdio_readsb - read from a FIFO on a SDIO function
517 * @func: SDIO function to access
518 * @dst: buffer to store the data
519 * @addr: address of (single byte) FIFO
520 * @count: number of bytes to read
521 *
522 * Reads from the specified FIFO of a given SDIO function. Return
523 * value indicates if the transfer succeeded or not.
524 */
sdio_readsb(struct sdio_func * func,void * dst,unsigned int addr,int count)525 int sdio_readsb(struct sdio_func *func, void *dst, unsigned int addr,
526 int count)
527 {
528 return sdio_io_rw_ext_helper(func, 0, addr, 0, dst, count);
529 }
530 EXPORT_SYMBOL_GPL(sdio_readsb);
531
532 /**
533 * sdio_writesb - write to a FIFO of a SDIO function
534 * @func: SDIO function to access
535 * @addr: address of (single byte) FIFO
536 * @src: buffer that contains the data to write
537 * @count: number of bytes to write
538 *
539 * Writes to the specified FIFO of a given SDIO function. Return
540 * value indicates if the transfer succeeded or not.
541 */
sdio_writesb(struct sdio_func * func,unsigned int addr,void * src,int count)542 int sdio_writesb(struct sdio_func *func, unsigned int addr, void *src,
543 int count)
544 {
545 return sdio_io_rw_ext_helper(func, 1, addr, 0, src, count);
546 }
547 EXPORT_SYMBOL_GPL(sdio_writesb);
548
549 /**
550 * sdio_readw - read a 16 bit integer from a SDIO function
551 * @func: SDIO function to access
552 * @addr: address to read
553 * @err_ret: optional status value from transfer
554 *
555 * Reads a 16 bit integer from the address space of a given SDIO
556 * function. If there is a problem reading the address, 0xffff
557 * is returned and @err_ret will contain the error code.
558 */
sdio_readw(struct sdio_func * func,unsigned int addr,int * err_ret)559 u16 sdio_readw(struct sdio_func *func, unsigned int addr, int *err_ret)
560 {
561 int ret;
562
563 if (err_ret)
564 *err_ret = 0;
565
566 ret = sdio_memcpy_fromio(func, func->tmpbuf, addr, 2);
567 if (ret) {
568 if (err_ret)
569 *err_ret = ret;
570 return 0xFFFF;
571 }
572
573 return le16_to_cpup((__le16 *)func->tmpbuf);
574 }
575 EXPORT_SYMBOL_GPL(sdio_readw);
576
577 /**
578 * sdio_writew - write a 16 bit integer to a SDIO function
579 * @func: SDIO function to access
580 * @b: integer to write
581 * @addr: address to write to
582 * @err_ret: optional status value from transfer
583 *
584 * Writes a 16 bit integer to the address space of a given SDIO
585 * function. @err_ret will contain the status of the actual
586 * transfer.
587 */
sdio_writew(struct sdio_func * func,u16 b,unsigned int addr,int * err_ret)588 void sdio_writew(struct sdio_func *func, u16 b, unsigned int addr, int *err_ret)
589 {
590 int ret;
591
592 *(__le16 *)func->tmpbuf = cpu_to_le16(b);
593
594 ret = sdio_memcpy_toio(func, addr, func->tmpbuf, 2);
595 if (err_ret)
596 *err_ret = ret;
597 }
598 EXPORT_SYMBOL_GPL(sdio_writew);
599
600 /**
601 * sdio_readl - read a 32 bit integer from a SDIO function
602 * @func: SDIO function to access
603 * @addr: address to read
604 * @err_ret: optional status value from transfer
605 *
606 * Reads a 32 bit integer from the address space of a given SDIO
607 * function. If there is a problem reading the address,
608 * 0xffffffff is returned and @err_ret will contain the error
609 * code.
610 */
sdio_readl(struct sdio_func * func,unsigned int addr,int * err_ret)611 u32 sdio_readl(struct sdio_func *func, unsigned int addr, int *err_ret)
612 {
613 int ret;
614
615 if (err_ret)
616 *err_ret = 0;
617
618 ret = sdio_memcpy_fromio(func, func->tmpbuf, addr, 4);
619 if (ret) {
620 if (err_ret)
621 *err_ret = ret;
622 return 0xFFFFFFFF;
623 }
624
625 return le32_to_cpup((__le32 *)func->tmpbuf);
626 }
627 EXPORT_SYMBOL_GPL(sdio_readl);
628
629 /**
630 * sdio_writel - write a 32 bit integer to a SDIO function
631 * @func: SDIO function to access
632 * @b: integer to write
633 * @addr: address to write to
634 * @err_ret: optional status value from transfer
635 *
636 * Writes a 32 bit integer to the address space of a given SDIO
637 * function. @err_ret will contain the status of the actual
638 * transfer.
639 */
sdio_writel(struct sdio_func * func,u32 b,unsigned int addr,int * err_ret)640 void sdio_writel(struct sdio_func *func, u32 b, unsigned int addr, int *err_ret)
641 {
642 int ret;
643
644 *(__le32 *)func->tmpbuf = cpu_to_le32(b);
645
646 ret = sdio_memcpy_toio(func, addr, func->tmpbuf, 4);
647 if (err_ret)
648 *err_ret = ret;
649 }
650 EXPORT_SYMBOL_GPL(sdio_writel);
651
652 /**
653 * sdio_f0_readb - read a single byte from SDIO function 0
654 * @func: an SDIO function of the card
655 * @addr: address to read
656 * @err_ret: optional status value from transfer
657 *
658 * Reads a single byte from the address space of SDIO function 0.
659 * If there is a problem reading the address, 0xff is returned
660 * and @err_ret will contain the error code.
661 */
sdio_f0_readb(struct sdio_func * func,unsigned int addr,int * err_ret)662 unsigned char sdio_f0_readb(struct sdio_func *func, unsigned int addr,
663 int *err_ret)
664 {
665 int ret;
666 unsigned char val;
667
668 if (!func) {
669 *err_ret = -EINVAL;
670 return 0xFF;
671 }
672
673 if (err_ret)
674 *err_ret = 0;
675
676 ret = mmc_io_rw_direct(func->card, 0, 0, addr, 0, &val);
677 if (ret) {
678 if (err_ret)
679 *err_ret = ret;
680 return 0xFF;
681 }
682
683 return val;
684 }
685 EXPORT_SYMBOL_GPL(sdio_f0_readb);
686
687 /**
688 * sdio_f0_writeb - write a single byte to SDIO function 0
689 * @func: an SDIO function of the card
690 * @b: byte to write
691 * @addr: address to write to
692 * @err_ret: optional status value from transfer
693 *
694 * Writes a single byte to the address space of SDIO function 0.
695 * @err_ret will contain the status of the actual transfer.
696 *
697 * Only writes to the vendor specific CCCR registers (0xF0 -
698 * 0xFF) are permiited; @err_ret will be set to -EINVAL for *
699 * writes outside this range.
700 */
sdio_f0_writeb(struct sdio_func * func,unsigned char b,unsigned int addr,int * err_ret)701 void sdio_f0_writeb(struct sdio_func *func, unsigned char b, unsigned int addr,
702 int *err_ret)
703 {
704 int ret;
705
706 if (!func) {
707 *err_ret = -EINVAL;
708 return;
709 }
710
711 if ((addr < 0xF0 || addr > 0xFF) && (!mmc_card_lenient_fn0(func->card))) {
712 if (err_ret)
713 *err_ret = -EINVAL;
714 return;
715 }
716
717 ret = mmc_io_rw_direct(func->card, 1, 0, addr, b, NULL);
718 if (err_ret)
719 *err_ret = ret;
720 }
721 EXPORT_SYMBOL_GPL(sdio_f0_writeb);
722
723 /**
724 * sdio_get_host_pm_caps - get host power management capabilities
725 * @func: SDIO function attached to host
726 *
727 * Returns a capability bitmask corresponding to power management
728 * features supported by the host controller that the card function
729 * might rely upon during a system suspend. The host doesn't need
730 * to be claimed, nor the function active, for this information to be
731 * obtained.
732 */
sdio_get_host_pm_caps(struct sdio_func * func)733 mmc_pm_flag_t sdio_get_host_pm_caps(struct sdio_func *func)
734 {
735 if (!func)
736 return 0;
737
738 return func->card->host->pm_caps;
739 }
740 EXPORT_SYMBOL_GPL(sdio_get_host_pm_caps);
741
742 /**
743 * sdio_set_host_pm_flags - set wanted host power management capabilities
744 * @func: SDIO function attached to host
745 *
746 * Set a capability bitmask corresponding to wanted host controller
747 * power management features for the upcoming suspend state.
748 * This must be called, if needed, each time the suspend method of
749 * the function driver is called, and must contain only bits that
750 * were returned by sdio_get_host_pm_caps().
751 * The host doesn't need to be claimed, nor the function active,
752 * for this information to be set.
753 */
sdio_set_host_pm_flags(struct sdio_func * func,mmc_pm_flag_t flags)754 int sdio_set_host_pm_flags(struct sdio_func *func, mmc_pm_flag_t flags)
755 {
756 struct mmc_host *host;
757
758 if (!func)
759 return -EINVAL;
760
761 host = func->card->host;
762
763 if (flags & ~host->pm_caps)
764 return -EINVAL;
765
766 /* function suspend methods are serialized, hence no lock needed */
767 host->pm_flags |= flags;
768 return 0;
769 }
770 EXPORT_SYMBOL_GPL(sdio_set_host_pm_flags);
771