xref: /openbmc/linux/drivers/mmc/core/sdio_io.c (revision 930ba0cb)
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  */
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, &reg);
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, &reg);
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, &reg);
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 ret;
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  * 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  */
_sdio_align_size(unsigned int sz)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  */
sdio_align_size(struct sdio_func * func,unsigned int sz)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. */
sdio_io_rw_ext_helper(struct sdio_func * func,int write,unsigned addr,int incr_addr,u8 * buf,unsigned size)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  */
sdio_readb(struct sdio_func * func,unsigned int addr,int * err_ret)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  */
sdio_writeb(struct sdio_func * func,u8 b,unsigned int addr,int * err_ret)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  */
sdio_writeb_readb(struct sdio_func * func,u8 write_byte,unsigned int addr,int * err_ret)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  */
sdio_memcpy_fromio(struct sdio_func * func,void * dst,unsigned int addr,int count)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  */
sdio_memcpy_toio(struct sdio_func * func,unsigned int addr,void * src,int count)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  */
sdio_readsb(struct sdio_func * func,void * dst,unsigned int addr,int count)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  */
sdio_writesb(struct sdio_func * func,unsigned int addr,void * src,int count)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  */
sdio_readw(struct sdio_func * func,unsigned int addr,int * err_ret)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  */
sdio_writew(struct sdio_func * func,u16 b,unsigned int addr,int * err_ret)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  */
sdio_readl(struct sdio_func * func,unsigned int addr,int * err_ret)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  */
sdio_writel(struct sdio_func * func,u32 b,unsigned int addr,int * err_ret)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  */
sdio_f0_readb(struct sdio_func * func,unsigned int addr,int * err_ret)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  */
sdio_f0_writeb(struct sdio_func * func,unsigned char b,unsigned int addr,int * err_ret)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  */
sdio_get_host_pm_caps(struct sdio_func * func)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  *	@flags: Power Management flags to set
713  *
714  *	Set a capability bitmask corresponding to wanted host controller
715  *	power management features for the upcoming suspend state.
716  *	This must be called, if needed, each time the suspend method of
717  *	the function driver is called, and must contain only bits that
718  *	were returned by sdio_get_host_pm_caps().
719  *	The host doesn't need to be claimed, nor the function active,
720  *	for this information to be set.
721  */
sdio_set_host_pm_flags(struct sdio_func * func,mmc_pm_flag_t flags)722 int sdio_set_host_pm_flags(struct sdio_func *func, mmc_pm_flag_t flags)
723 {
724 	struct mmc_host *host;
725 
726 	if (!func)
727 		return -EINVAL;
728 
729 	host = func->card->host;
730 
731 	if (flags & ~host->pm_caps)
732 		return -EINVAL;
733 
734 	/* function suspend methods are serialized, hence no lock needed */
735 	host->pm_flags |= flags;
736 	return 0;
737 }
738 EXPORT_SYMBOL_GPL(sdio_set_host_pm_flags);
739 
740 /**
741  *	sdio_retune_crc_disable - temporarily disable retuning on CRC errors
742  *	@func: SDIO function attached to host
743  *
744  *	If the SDIO card is known to be in a state where it might produce
745  *	CRC errors on the bus in response to commands (like if we know it is
746  *	transitioning between power states), an SDIO function driver can
747  *	call this function to temporarily disable the SD/MMC core behavior of
748  *	triggering an automatic retuning.
749  *
750  *	This function should be called while the host is claimed and the host
751  *	should remain claimed until sdio_retune_crc_enable() is called.
752  *	Specifically, the expected sequence of calls is:
753  *	- sdio_claim_host()
754  *	- sdio_retune_crc_disable()
755  *	- some number of calls like sdio_writeb() and sdio_readb()
756  *	- sdio_retune_crc_enable()
757  *	- sdio_release_host()
758  */
sdio_retune_crc_disable(struct sdio_func * func)759 void sdio_retune_crc_disable(struct sdio_func *func)
760 {
761 	func->card->host->retune_crc_disable = true;
762 }
763 EXPORT_SYMBOL_GPL(sdio_retune_crc_disable);
764 
765 /**
766  *	sdio_retune_crc_enable - re-enable retuning on CRC errors
767  *	@func: SDIO function attached to host
768  *
769  *	This is the complement to sdio_retune_crc_disable().
770  */
sdio_retune_crc_enable(struct sdio_func * func)771 void sdio_retune_crc_enable(struct sdio_func *func)
772 {
773 	func->card->host->retune_crc_disable = false;
774 }
775 EXPORT_SYMBOL_GPL(sdio_retune_crc_enable);
776 
777 /**
778  *	sdio_retune_hold_now - start deferring retuning requests till release
779  *	@func: SDIO function attached to host
780  *
781  *	This function can be called if it's currently a bad time to do
782  *	a retune of the SDIO card.  Retune requests made during this time
783  *	will be held and we'll actually do the retune sometime after the
784  *	release.
785  *
786  *	This function could be useful if an SDIO card is in a power state
787  *	where it can respond to a small subset of commands that doesn't
788  *	include the retuning command.  Care should be taken when using
789  *	this function since (presumably) the retuning request we might be
790  *	deferring was made for a good reason.
791  *
792  *	This function should be called while the host is claimed.
793  */
sdio_retune_hold_now(struct sdio_func * func)794 void sdio_retune_hold_now(struct sdio_func *func)
795 {
796 	mmc_retune_hold_now(func->card->host);
797 }
798 EXPORT_SYMBOL_GPL(sdio_retune_hold_now);
799 
800 /**
801  *	sdio_retune_release - signal that it's OK to retune now
802  *	@func: SDIO function attached to host
803  *
804  *	This is the complement to sdio_retune_hold_now().  Calling this
805  *	function won't make a retune happen right away but will allow
806  *	them to be scheduled normally.
807  *
808  *	This function should be called while the host is claimed.
809  */
sdio_retune_release(struct sdio_func * func)810 void sdio_retune_release(struct sdio_func *func)
811 {
812 	mmc_retune_release(func->card->host);
813 }
814 EXPORT_SYMBOL_GPL(sdio_retune_release);
815