xref: /openbmc/linux/drivers/mmc/core/sdio.c (revision 367b8112)
1 /*
2  *  linux/drivers/mmc/sdio.c
3  *
4  *  Copyright 2006-2007 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/err.h>
13 
14 #include <linux/mmc/host.h>
15 #include <linux/mmc/card.h>
16 #include <linux/mmc/sdio.h>
17 #include <linux/mmc/sdio_func.h>
18 
19 #include "core.h"
20 #include "bus.h"
21 #include "sdio_bus.h"
22 #include "mmc_ops.h"
23 #include "sd_ops.h"
24 #include "sdio_ops.h"
25 #include "sdio_cis.h"
26 
27 static int sdio_read_fbr(struct sdio_func *func)
28 {
29 	int ret;
30 	unsigned char data;
31 
32 	ret = mmc_io_rw_direct(func->card, 0, 0,
33 		SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF, 0, &data);
34 	if (ret)
35 		goto out;
36 
37 	data &= 0x0f;
38 
39 	if (data == 0x0f) {
40 		ret = mmc_io_rw_direct(func->card, 0, 0,
41 			SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF_EXT, 0, &data);
42 		if (ret)
43 			goto out;
44 	}
45 
46 	func->class = data;
47 
48 out:
49 	return ret;
50 }
51 
52 static int sdio_init_func(struct mmc_card *card, unsigned int fn)
53 {
54 	int ret;
55 	struct sdio_func *func;
56 
57 	BUG_ON(fn > SDIO_MAX_FUNCS);
58 
59 	func = sdio_alloc_func(card);
60 	if (IS_ERR(func))
61 		return PTR_ERR(func);
62 
63 	func->num = fn;
64 
65 	ret = sdio_read_fbr(func);
66 	if (ret)
67 		goto fail;
68 
69 	ret = sdio_read_func_cis(func);
70 	if (ret)
71 		goto fail;
72 
73 	card->sdio_func[fn - 1] = func;
74 
75 	return 0;
76 
77 fail:
78 	/*
79 	 * It is okay to remove the function here even though we hold
80 	 * the host lock as we haven't registered the device yet.
81 	 */
82 	sdio_remove_func(func);
83 	return ret;
84 }
85 
86 static int sdio_read_cccr(struct mmc_card *card)
87 {
88 	int ret;
89 	int cccr_vsn;
90 	unsigned char data;
91 
92 	memset(&card->cccr, 0, sizeof(struct sdio_cccr));
93 
94 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CCCR, 0, &data);
95 	if (ret)
96 		goto out;
97 
98 	cccr_vsn = data & 0x0f;
99 
100 	if (cccr_vsn > SDIO_CCCR_REV_1_20) {
101 		printk(KERN_ERR "%s: unrecognised CCCR structure version %d\n",
102 			mmc_hostname(card->host), cccr_vsn);
103 		return -EINVAL;
104 	}
105 
106 	card->cccr.sdio_vsn = (data & 0xf0) >> 4;
107 
108 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CAPS, 0, &data);
109 	if (ret)
110 		goto out;
111 
112 	if (data & SDIO_CCCR_CAP_SMB)
113 		card->cccr.multi_block = 1;
114 	if (data & SDIO_CCCR_CAP_LSC)
115 		card->cccr.low_speed = 1;
116 	if (data & SDIO_CCCR_CAP_4BLS)
117 		card->cccr.wide_bus = 1;
118 
119 	if (cccr_vsn >= SDIO_CCCR_REV_1_10) {
120 		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_POWER, 0, &data);
121 		if (ret)
122 			goto out;
123 
124 		if (data & SDIO_POWER_SMPC)
125 			card->cccr.high_power = 1;
126 	}
127 
128 	if (cccr_vsn >= SDIO_CCCR_REV_1_20) {
129 		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &data);
130 		if (ret)
131 			goto out;
132 
133 		if (data & SDIO_SPEED_SHS)
134 			card->cccr.high_speed = 1;
135 	}
136 
137 out:
138 	return ret;
139 }
140 
141 static int sdio_enable_wide(struct mmc_card *card)
142 {
143 	int ret;
144 	u8 ctrl;
145 
146 	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
147 		return 0;
148 
149 	if (card->cccr.low_speed && !card->cccr.wide_bus)
150 		return 0;
151 
152 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
153 	if (ret)
154 		return ret;
155 
156 	ctrl |= SDIO_BUS_WIDTH_4BIT;
157 
158 	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
159 	if (ret)
160 		return ret;
161 
162 	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
163 
164 	return 0;
165 }
166 
167 /*
168  * Test if the card supports high-speed mode and, if so, switch to it.
169  */
170 static int sdio_enable_hs(struct mmc_card *card)
171 {
172 	int ret;
173 	u8 speed;
174 
175 	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
176 		return 0;
177 
178 	if (!card->cccr.high_speed)
179 		return 0;
180 
181 	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
182 	if (ret)
183 		return ret;
184 
185 	speed |= SDIO_SPEED_EHS;
186 
187 	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
188 	if (ret)
189 		return ret;
190 
191 	mmc_card_set_highspeed(card);
192 	mmc_set_timing(card->host, MMC_TIMING_SD_HS);
193 
194 	return 0;
195 }
196 
197 /*
198  * Host is being removed. Free up the current card.
199  */
200 static void mmc_sdio_remove(struct mmc_host *host)
201 {
202 	int i;
203 
204 	BUG_ON(!host);
205 	BUG_ON(!host->card);
206 
207 	for (i = 0;i < host->card->sdio_funcs;i++) {
208 		if (host->card->sdio_func[i]) {
209 			sdio_remove_func(host->card->sdio_func[i]);
210 			host->card->sdio_func[i] = NULL;
211 		}
212 	}
213 
214 	mmc_remove_card(host->card);
215 	host->card = NULL;
216 }
217 
218 /*
219  * Card detection callback from host.
220  */
221 static void mmc_sdio_detect(struct mmc_host *host)
222 {
223 	int err;
224 
225 	BUG_ON(!host);
226 	BUG_ON(!host->card);
227 
228 	mmc_claim_host(host);
229 
230 	/*
231 	 * Just check if our card has been removed.
232 	 */
233 	err = mmc_select_card(host->card);
234 
235 	mmc_release_host(host);
236 
237 	if (err) {
238 		mmc_sdio_remove(host);
239 
240 		mmc_claim_host(host);
241 		mmc_detach_bus(host);
242 		mmc_release_host(host);
243 	}
244 }
245 
246 
247 static const struct mmc_bus_ops mmc_sdio_ops = {
248 	.remove = mmc_sdio_remove,
249 	.detect = mmc_sdio_detect,
250 };
251 
252 
253 /*
254  * Starting point for SDIO card init.
255  */
256 int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
257 {
258 	int err;
259 	int i, funcs;
260 	struct mmc_card *card;
261 
262 	BUG_ON(!host);
263 	WARN_ON(!host->claimed);
264 
265 	mmc_attach_bus(host, &mmc_sdio_ops);
266 
267 	/*
268 	 * Sanity check the voltages that the card claims to
269 	 * support.
270 	 */
271 	if (ocr & 0x7F) {
272 		printk(KERN_WARNING "%s: card claims to support voltages "
273 		       "below the defined range. These will be ignored.\n",
274 		       mmc_hostname(host));
275 		ocr &= ~0x7F;
276 	}
277 
278 	if (ocr & MMC_VDD_165_195) {
279 		printk(KERN_WARNING "%s: SDIO card claims to support the "
280 		       "incompletely defined 'low voltage range'. This "
281 		       "will be ignored.\n", mmc_hostname(host));
282 		ocr &= ~MMC_VDD_165_195;
283 	}
284 
285 	host->ocr = mmc_select_voltage(host, ocr);
286 
287 	/*
288 	 * Can we support the voltage(s) of the card(s)?
289 	 */
290 	if (!host->ocr) {
291 		err = -EINVAL;
292 		goto err;
293 	}
294 
295 	/*
296 	 * Inform the card of the voltage
297 	 */
298 	err = mmc_send_io_op_cond(host, host->ocr, &ocr);
299 	if (err)
300 		goto err;
301 
302 	/*
303 	 * For SPI, enable CRC as appropriate.
304 	 */
305 	if (mmc_host_is_spi(host)) {
306 		err = mmc_spi_set_crc(host, use_spi_crc);
307 		if (err)
308 			goto err;
309 	}
310 
311 	/*
312 	 * The number of functions on the card is encoded inside
313 	 * the ocr.
314 	 */
315 	funcs = (ocr & 0x70000000) >> 28;
316 
317 	/*
318 	 * Allocate card structure.
319 	 */
320 	card = mmc_alloc_card(host, NULL);
321 	if (IS_ERR(card)) {
322 		err = PTR_ERR(card);
323 		goto err;
324 	}
325 
326 	card->type = MMC_TYPE_SDIO;
327 	card->sdio_funcs = funcs;
328 
329 	host->card = card;
330 
331 	/*
332 	 * For native busses:  set card RCA and quit open drain mode.
333 	 */
334 	if (!mmc_host_is_spi(host)) {
335 		err = mmc_send_relative_addr(host, &card->rca);
336 		if (err)
337 			goto remove;
338 
339 		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
340 	}
341 
342 	/*
343 	 * Select card, as all following commands rely on that.
344 	 */
345 	if (!mmc_host_is_spi(host)) {
346 		err = mmc_select_card(card);
347 		if (err)
348 			goto remove;
349 	}
350 
351 	/*
352 	 * Read the common registers.
353 	 */
354 	err = sdio_read_cccr(card);
355 	if (err)
356 		goto remove;
357 
358 	/*
359 	 * Read the common CIS tuples.
360 	 */
361 	err = sdio_read_common_cis(card);
362 	if (err)
363 		goto remove;
364 
365 	/*
366 	 * Switch to high-speed (if supported).
367 	 */
368 	err = sdio_enable_hs(card);
369 	if (err)
370 		goto remove;
371 
372 	/*
373 	 * Change to the card's maximum speed.
374 	 */
375 	if (mmc_card_highspeed(card)) {
376 		/*
377 		 * The SDIO specification doesn't mention how
378 		 * the CIS transfer speed register relates to
379 		 * high-speed, but it seems that 50 MHz is
380 		 * mandatory.
381 		 */
382 		mmc_set_clock(host, 50000000);
383 	} else {
384 		mmc_set_clock(host, card->cis.max_dtr);
385 	}
386 
387 	/*
388 	 * Switch to wider bus (if supported).
389 	 */
390 	err = sdio_enable_wide(card);
391 	if (err)
392 		goto remove;
393 
394 	/*
395 	 * Initialize (but don't add) all present functions.
396 	 */
397 	for (i = 0;i < funcs;i++) {
398 		err = sdio_init_func(host->card, i + 1);
399 		if (err)
400 			goto remove;
401 	}
402 
403 	mmc_release_host(host);
404 
405 	/*
406 	 * First add the card to the driver model...
407 	 */
408 	err = mmc_add_card(host->card);
409 	if (err)
410 		goto remove_added;
411 
412 	/*
413 	 * ...then the SDIO functions.
414 	 */
415 	for (i = 0;i < funcs;i++) {
416 		err = sdio_add_func(host->card->sdio_func[i]);
417 		if (err)
418 			goto remove_added;
419 	}
420 
421 	return 0;
422 
423 
424 remove_added:
425 	/* Remove without lock if the device has been added. */
426 	mmc_sdio_remove(host);
427 	mmc_claim_host(host);
428 remove:
429 	/* And with lock if it hasn't been added. */
430 	if (host->card)
431 		mmc_sdio_remove(host);
432 err:
433 	mmc_detach_bus(host);
434 	mmc_release_host(host);
435 
436 	printk(KERN_ERR "%s: error %d whilst initialising SDIO card\n",
437 		mmc_hostname(host), err);
438 
439 	return err;
440 }
441 
442