xref: /openbmc/linux/drivers/mmc/core/sdio.c (revision 93dc544c)
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  * Host is being removed. Free up the current card.
169  */
170 static void mmc_sdio_remove(struct mmc_host *host)
171 {
172 	int i;
173 
174 	BUG_ON(!host);
175 	BUG_ON(!host->card);
176 
177 	for (i = 0;i < host->card->sdio_funcs;i++) {
178 		if (host->card->sdio_func[i]) {
179 			sdio_remove_func(host->card->sdio_func[i]);
180 			host->card->sdio_func[i] = NULL;
181 		}
182 	}
183 
184 	mmc_remove_card(host->card);
185 	host->card = NULL;
186 }
187 
188 /*
189  * Card detection callback from host.
190  */
191 static void mmc_sdio_detect(struct mmc_host *host)
192 {
193 	int err;
194 
195 	BUG_ON(!host);
196 	BUG_ON(!host->card);
197 
198 	mmc_claim_host(host);
199 
200 	/*
201 	 * Just check if our card has been removed.
202 	 */
203 	err = mmc_select_card(host->card);
204 
205 	mmc_release_host(host);
206 
207 	if (err) {
208 		mmc_sdio_remove(host);
209 
210 		mmc_claim_host(host);
211 		mmc_detach_bus(host);
212 		mmc_release_host(host);
213 	}
214 }
215 
216 
217 static const struct mmc_bus_ops mmc_sdio_ops = {
218 	.remove = mmc_sdio_remove,
219 	.detect = mmc_sdio_detect,
220 };
221 
222 
223 /*
224  * Starting point for SDIO card init.
225  */
226 int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
227 {
228 	int err;
229 	int i, funcs;
230 	struct mmc_card *card;
231 
232 	BUG_ON(!host);
233 	WARN_ON(!host->claimed);
234 
235 	mmc_attach_bus(host, &mmc_sdio_ops);
236 
237 	/*
238 	 * Sanity check the voltages that the card claims to
239 	 * support.
240 	 */
241 	if (ocr & 0x7F) {
242 		printk(KERN_WARNING "%s: card claims to support voltages "
243 		       "below the defined range. These will be ignored.\n",
244 		       mmc_hostname(host));
245 		ocr &= ~0x7F;
246 	}
247 
248 	if (ocr & MMC_VDD_165_195) {
249 		printk(KERN_WARNING "%s: SDIO card claims to support the "
250 		       "incompletely defined 'low voltage range'. This "
251 		       "will be ignored.\n", mmc_hostname(host));
252 		ocr &= ~MMC_VDD_165_195;
253 	}
254 
255 	host->ocr = mmc_select_voltage(host, ocr);
256 
257 	/*
258 	 * Can we support the voltage(s) of the card(s)?
259 	 */
260 	if (!host->ocr) {
261 		err = -EINVAL;
262 		goto err;
263 	}
264 
265 	/*
266 	 * Inform the card of the voltage
267 	 */
268 	err = mmc_send_io_op_cond(host, host->ocr, &ocr);
269 	if (err)
270 		goto err;
271 
272 	/*
273 	 * For SPI, enable CRC as appropriate.
274 	 */
275 	if (mmc_host_is_spi(host)) {
276 		err = mmc_spi_set_crc(host, use_spi_crc);
277 		if (err)
278 			goto err;
279 	}
280 
281 	/*
282 	 * The number of functions on the card is encoded inside
283 	 * the ocr.
284 	 */
285 	funcs = (ocr & 0x70000000) >> 28;
286 
287 	/*
288 	 * Allocate card structure.
289 	 */
290 	card = mmc_alloc_card(host, NULL);
291 	if (IS_ERR(card)) {
292 		err = PTR_ERR(card);
293 		goto err;
294 	}
295 
296 	card->type = MMC_TYPE_SDIO;
297 	card->sdio_funcs = funcs;
298 
299 	host->card = card;
300 
301 	/*
302 	 * For native busses:  set card RCA and quit open drain mode.
303 	 */
304 	if (!mmc_host_is_spi(host)) {
305 		err = mmc_send_relative_addr(host, &card->rca);
306 		if (err)
307 			goto remove;
308 
309 		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
310 	}
311 
312 	/*
313 	 * Select card, as all following commands rely on that.
314 	 */
315 	if (!mmc_host_is_spi(host)) {
316 		err = mmc_select_card(card);
317 		if (err)
318 			goto remove;
319 	}
320 
321 	/*
322 	 * Read the common registers.
323 	 */
324 	err = sdio_read_cccr(card);
325 	if (err)
326 		goto remove;
327 
328 	/*
329 	 * Read the common CIS tuples.
330 	 */
331 	err = sdio_read_common_cis(card);
332 	if (err)
333 		goto remove;
334 
335 	/*
336 	 * No support for high-speed yet, so just set
337 	 * the card's maximum speed.
338 	 */
339 	mmc_set_clock(host, card->cis.max_dtr);
340 
341 	/*
342 	 * Switch to wider bus (if supported).
343 	 */
344 	err = sdio_enable_wide(card);
345 	if (err)
346 		goto remove;
347 
348 	/*
349 	 * Initialize (but don't add) all present functions.
350 	 */
351 	for (i = 0;i < funcs;i++) {
352 		err = sdio_init_func(host->card, i + 1);
353 		if (err)
354 			goto remove;
355 	}
356 
357 	mmc_release_host(host);
358 
359 	/*
360 	 * First add the card to the driver model...
361 	 */
362 	err = mmc_add_card(host->card);
363 	if (err)
364 		goto remove_added;
365 
366 	/*
367 	 * ...then the SDIO functions.
368 	 */
369 	for (i = 0;i < funcs;i++) {
370 		err = sdio_add_func(host->card->sdio_func[i]);
371 		if (err)
372 			goto remove_added;
373 	}
374 
375 	return 0;
376 
377 
378 remove_added:
379 	/* Remove without lock if the device has been added. */
380 	mmc_sdio_remove(host);
381 	mmc_claim_host(host);
382 remove:
383 	/* And with lock if it hasn't been added. */
384 	if (host->card)
385 		mmc_sdio_remove(host);
386 err:
387 	mmc_detach_bus(host);
388 	mmc_release_host(host);
389 
390 	printk(KERN_ERR "%s: error %d whilst initialising SDIO card\n",
391 		mmc_hostname(host), err);
392 
393 	return err;
394 }
395 
396