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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, &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 -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