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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/drivers/mmc/core/host.c
4 *
5 * Copyright (C) 2003 Russell King, All Rights Reserved.
6 * Copyright (C) 2007-2008 Pierre Ossman
7 * Copyright (C) 2010 Linus Walleij
8 *
9 * MMC host class device management
10 */
11
12#include <linux/device.h>
13#include <linux/err.h>
14#include <linux/idr.h>
15#include <linux/of.h>
16#include <linux/pagemap.h>
17#include <linux/pm_wakeup.h>
18#include <linux/export.h>
19#include <linux/leds.h>
20#include <linux/slab.h>
21
22#include <linux/mmc/host.h>
23#include <linux/mmc/card.h>
24#include <linux/mmc/slot-gpio.h>
25
26#include "core.h"
27#include "crypto.h"
28#include "host.h"
29#include "slot-gpio.h"
30#include "pwrseq.h"
31#include "sdio_ops.h"
32
33#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
34
35static DEFINE_IDA(mmc_host_ida);
36
37#ifdef CONFIG_PM_SLEEP
38static int mmc_host_class_prepare(struct device *dev)
39{
40 struct mmc_host *host = cls_dev_to_mmc_host(dev);
41
42 /*
43 * It's safe to access the bus_ops pointer, as both userspace and the
44 * workqueue for detecting cards are frozen at this point.
45 */
46 if (!host->bus_ops)
47 return 0;
48
49 /* Validate conditions for system suspend. */
50 if (host->bus_ops->pre_suspend)
51 return host->bus_ops->pre_suspend(host);
52
53 return 0;
54}
55
56static void mmc_host_class_complete(struct device *dev)
57{
58 struct mmc_host *host = cls_dev_to_mmc_host(dev);
59
60 _mmc_detect_change(host, 0, false);
61}
62
63static const struct dev_pm_ops mmc_host_class_dev_pm_ops = {
64 .prepare = mmc_host_class_prepare,
65 .complete = mmc_host_class_complete,
66};
67
68#define MMC_HOST_CLASS_DEV_PM_OPS (&mmc_host_class_dev_pm_ops)
69#else
70#define MMC_HOST_CLASS_DEV_PM_OPS NULL
71#endif
72
73static void mmc_host_classdev_release(struct device *dev)
74{
75 struct mmc_host *host = cls_dev_to_mmc_host(dev);
76 wakeup_source_unregister(host->ws);
77 if (of_alias_get_id(host->parent->of_node, "mmc") < 0)
78 ida_free(&mmc_host_ida, host->index);
79 kfree(host);
80}
81
82static int mmc_host_classdev_shutdown(struct device *dev)
83{
84 struct mmc_host *host = cls_dev_to_mmc_host(dev);
85
86 __mmc_stop_host(host);
87 return 0;
88}
89
90static const struct class mmc_host_class = {
91 .name = "mmc_host",
92 .dev_release = mmc_host_classdev_release,
93 .shutdown_pre = mmc_host_classdev_shutdown,
94 .pm = MMC_HOST_CLASS_DEV_PM_OPS,
95};
96
97int mmc_register_host_class(void)
98{
99 return class_register(&mmc_host_class);
100}
101
102void mmc_unregister_host_class(void)
103{
104 class_unregister(&mmc_host_class);
105}
106
107/**
108 * mmc_retune_enable() - enter a transfer mode that requires retuning
109 * @host: host which should retune now
110 */
111void mmc_retune_enable(struct mmc_host *host)
112{
113 host->can_retune = 1;
114 if (host->retune_period)
115 mod_timer(&host->retune_timer,
116 jiffies + host->retune_period * HZ);
117}
118
119/*
120 * Pause re-tuning for a small set of operations. The pause begins after the
121 * next command.
122 */
123void mmc_retune_pause(struct mmc_host *host)
124{
125 if (!host->retune_paused) {
126 host->retune_paused = 1;
127 mmc_retune_hold(host);
128 }
129}
130EXPORT_SYMBOL(mmc_retune_pause);
131
132void mmc_retune_unpause(struct mmc_host *host)
133{
134 if (host->retune_paused) {
135 host->retune_paused = 0;
136 mmc_retune_release(host);
137 }
138}
139EXPORT_SYMBOL(mmc_retune_unpause);
140
141/**
142 * mmc_retune_disable() - exit a transfer mode that requires retuning
143 * @host: host which should not retune anymore
144 *
145 * It is not meant for temporarily preventing retuning!
146 */
147void mmc_retune_disable(struct mmc_host *host)
148{
149 mmc_retune_unpause(host);
150 host->can_retune = 0;
151 del_timer_sync(&host->retune_timer);
152 mmc_retune_clear(host);
153}
154
155void mmc_retune_timer_stop(struct mmc_host *host)
156{
157 del_timer_sync(&host->retune_timer);
158}
159EXPORT_SYMBOL(mmc_retune_timer_stop);
160
161void mmc_retune_hold(struct mmc_host *host)
162{
163 if (!host->hold_retune)
164 host->retune_now = 1;
165 host->hold_retune += 1;
166}
167
168void mmc_retune_release(struct mmc_host *host)
169{
170 if (host->hold_retune)
171 host->hold_retune -= 1;
172 else
173 WARN_ON(1);
174}
175EXPORT_SYMBOL(mmc_retune_release);
176
177int mmc_retune(struct mmc_host *host)
178{
179 bool return_to_hs400 = false;
180 int err;
181
182 if (host->retune_now)
183 host->retune_now = 0;
184 else
185 return 0;
186
187 if (!host->need_retune || host->doing_retune || !host->card)
188 return 0;
189
190 host->need_retune = 0;
191
192 host->doing_retune = 1;
193
194 if (host->ios.timing == MMC_TIMING_MMC_HS400) {
195 err = mmc_hs400_to_hs200(host->card);
196 if (err)
197 goto out;
198
199 return_to_hs400 = true;
200 }
201
202 err = mmc_execute_tuning(host->card);
203 if (err)
204 goto out;
205
206 if (return_to_hs400)
207 err = mmc_hs200_to_hs400(host->card);
208out:
209 host->doing_retune = 0;
210
211 return err;
212}
213
214static void mmc_retune_timer(struct timer_list *t)
215{
216 struct mmc_host *host = from_timer(host, t, retune_timer);
217
218 mmc_retune_needed(host);
219}
220
221static void mmc_of_parse_timing_phase(struct device *dev, const char *prop,
222 struct mmc_clk_phase *phase)
223{
224 int degrees[2] = {0};
225 int rc;
226
227 rc = device_property_read_u32_array(dev, prop, degrees, 2);
228 phase->valid = !rc;
229 if (phase->valid) {
230 phase->in_deg = degrees[0];
231 phase->out_deg = degrees[1];
232 }
233}
234
235void
236mmc_of_parse_clk_phase(struct device *dev, struct mmc_clk_phase_map *map)
237{
238 mmc_of_parse_timing_phase(dev, "clk-phase-legacy",
239 &map->phase[MMC_TIMING_LEGACY]);
240 mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs",
241 &map->phase[MMC_TIMING_MMC_HS]);
242 mmc_of_parse_timing_phase(dev, "clk-phase-sd-hs",
243 &map->phase[MMC_TIMING_SD_HS]);
244 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr12",
245 &map->phase[MMC_TIMING_UHS_SDR12]);
246 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr25",
247 &map->phase[MMC_TIMING_UHS_SDR25]);
248 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr50",
249 &map->phase[MMC_TIMING_UHS_SDR50]);
250 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr104",
251 &map->phase[MMC_TIMING_UHS_SDR104]);
252 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-ddr50",
253 &map->phase[MMC_TIMING_UHS_DDR50]);
254 mmc_of_parse_timing_phase(dev, "clk-phase-mmc-ddr52",
255 &map->phase[MMC_TIMING_MMC_DDR52]);
256 mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs200",
257 &map->phase[MMC_TIMING_MMC_HS200]);
258 mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs400",
259 &map->phase[MMC_TIMING_MMC_HS400]);
260}
261EXPORT_SYMBOL(mmc_of_parse_clk_phase);
262
263/**
264 * mmc_of_parse() - parse host's device properties
265 * @host: host whose properties should be parsed.
266 *
267 * To keep the rest of the MMC subsystem unaware of whether DT has been
268 * used to instantiate and configure this host instance or not, we
269 * parse the properties and set respective generic mmc-host flags and
270 * parameters.
271 */
272int mmc_of_parse(struct mmc_host *host)
273{
274 struct device *dev = host->parent;
275 u32 bus_width, drv_type, cd_debounce_delay_ms;
276 int ret;
277
278 if (!dev || !dev_fwnode(dev))
279 return 0;
280
281 /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
282 if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) {
283 dev_dbg(host->parent,
284 "\"bus-width\" property is missing, assuming 1 bit.\n");
285 bus_width = 1;
286 }
287
288 switch (bus_width) {
289 case 8:
290 host->caps |= MMC_CAP_8_BIT_DATA;
291 fallthrough; /* Hosts capable of 8-bit can also do 4 bits */
292 case 4:
293 host->caps |= MMC_CAP_4_BIT_DATA;
294 break;
295 case 1:
296 break;
297 default:
298 dev_err(host->parent,
299 "Invalid \"bus-width\" value %u!\n", bus_width);
300 return -EINVAL;
301 }
302
303 /* f_max is obtained from the optional "max-frequency" property */
304 device_property_read_u32(dev, "max-frequency", &host->f_max);
305
306 /*
307 * Configure CD and WP pins. They are both by default active low to
308 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
309 * mmc-gpio helpers are used to attach, configure and use them. If
310 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
311 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
312 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
313 * is set. If the "non-removable" property is found, the
314 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
315 * configuration is performed.
316 */
317
318 /* Parse Card Detection */
319
320 if (device_property_read_bool(dev, "non-removable")) {
321 host->caps |= MMC_CAP_NONREMOVABLE;
322 } else {
323 if (device_property_read_bool(dev, "cd-inverted"))
324 host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
325
326 if (device_property_read_u32(dev, "cd-debounce-delay-ms",
327 &cd_debounce_delay_ms))
328 cd_debounce_delay_ms = 200;
329
330 if (device_property_read_bool(dev, "broken-cd"))
331 host->caps |= MMC_CAP_NEEDS_POLL;
332
333 ret = mmc_gpiod_request_cd(host, "cd", 0, false,
334 cd_debounce_delay_ms * 1000);
335 if (!ret)
336 dev_info(host->parent, "Got CD GPIO\n");
337 else if (ret != -ENOENT && ret != -ENOSYS)
338 return ret;
339 }
340
341 /* Parse Write Protection */
342
343 if (device_property_read_bool(dev, "wp-inverted"))
344 host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
345
346 ret = mmc_gpiod_request_ro(host, "wp", 0, 0);
347 if (!ret)
348 dev_info(host->parent, "Got WP GPIO\n");
349 else if (ret != -ENOENT && ret != -ENOSYS)
350 return ret;
351
352 if (device_property_read_bool(dev, "disable-wp"))
353 host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
354
355 if (device_property_read_bool(dev, "cap-sd-highspeed"))
356 host->caps |= MMC_CAP_SD_HIGHSPEED;
357 if (device_property_read_bool(dev, "cap-mmc-highspeed"))
358 host->caps |= MMC_CAP_MMC_HIGHSPEED;
359 if (device_property_read_bool(dev, "sd-uhs-sdr12"))
360 host->caps |= MMC_CAP_UHS_SDR12;
361 if (device_property_read_bool(dev, "sd-uhs-sdr25"))
362 host->caps |= MMC_CAP_UHS_SDR25;
363 if (device_property_read_bool(dev, "sd-uhs-sdr50"))
364 host->caps |= MMC_CAP_UHS_SDR50;
365 if (device_property_read_bool(dev, "sd-uhs-sdr104"))
366 host->caps |= MMC_CAP_UHS_SDR104;
367 if (device_property_read_bool(dev, "sd-uhs-ddr50"))
368 host->caps |= MMC_CAP_UHS_DDR50;
369 if (device_property_read_bool(dev, "cap-power-off-card"))
370 host->caps |= MMC_CAP_POWER_OFF_CARD;
371 if (device_property_read_bool(dev, "cap-mmc-hw-reset"))
372 host->caps |= MMC_CAP_HW_RESET;
373 if (device_property_read_bool(dev, "cap-sdio-irq"))
374 host->caps |= MMC_CAP_SDIO_IRQ;
375 if (device_property_read_bool(dev, "full-pwr-cycle"))
376 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
377 if (device_property_read_bool(dev, "full-pwr-cycle-in-suspend"))
378 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND;
379 if (device_property_read_bool(dev, "keep-power-in-suspend"))
380 host->pm_caps |= MMC_PM_KEEP_POWER;
381 if (device_property_read_bool(dev, "wakeup-source") ||
382 device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
383 host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
384 if (device_property_read_bool(dev, "mmc-ddr-3_3v"))
385 host->caps |= MMC_CAP_3_3V_DDR;
386 if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
387 host->caps |= MMC_CAP_1_8V_DDR;
388 if (device_property_read_bool(dev, "mmc-ddr-1_2v"))
389 host->caps |= MMC_CAP_1_2V_DDR;
390 if (device_property_read_bool(dev, "mmc-hs200-1_8v"))
391 host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
392 if (device_property_read_bool(dev, "mmc-hs200-1_2v"))
393 host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
394 if (device_property_read_bool(dev, "mmc-hs400-1_8v"))
395 host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
396 if (device_property_read_bool(dev, "mmc-hs400-1_2v"))
397 host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
398 if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe"))
399 host->caps2 |= MMC_CAP2_HS400_ES;
400 if (device_property_read_bool(dev, "no-sdio"))
401 host->caps2 |= MMC_CAP2_NO_SDIO;
402 if (device_property_read_bool(dev, "no-sd"))
403 host->caps2 |= MMC_CAP2_NO_SD;
404 if (device_property_read_bool(dev, "no-mmc"))
405 host->caps2 |= MMC_CAP2_NO_MMC;
406 if (device_property_read_bool(dev, "no-mmc-hs400"))
407 host->caps2 &= ~(MMC_CAP2_HS400_1_8V | MMC_CAP2_HS400_1_2V |
408 MMC_CAP2_HS400_ES);
409
410 /* Must be after "non-removable" check */
411 if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) {
412 if (host->caps & MMC_CAP_NONREMOVABLE)
413 host->fixed_drv_type = drv_type;
414 else
415 dev_err(host->parent,
416 "can't use fixed driver type, media is removable\n");
417 }
418
419 host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr);
420 if (host->dsr_req && (host->dsr & ~0xffff)) {
421 dev_err(host->parent,
422 "device tree specified broken value for DSR: 0x%x, ignoring\n",
423 host->dsr);
424 host->dsr_req = 0;
425 }
426
427 device_property_read_u32(dev, "post-power-on-delay-ms",
428 &host->ios.power_delay_ms);
429
430 return mmc_pwrseq_alloc(host);
431}
432
433EXPORT_SYMBOL(mmc_of_parse);
434
435/**
436 * mmc_of_parse_voltage - return mask of supported voltages
437 * @host: host whose properties should be parsed.
438 * @mask: mask of voltages available for MMC/SD/SDIO
439 *
440 * Parse the "voltage-ranges" property, returning zero if it is not
441 * found, negative errno if the voltage-range specification is invalid,
442 * or one if the voltage-range is specified and successfully parsed.
443 */
444int mmc_of_parse_voltage(struct mmc_host *host, u32 *mask)
445{
446 const char *prop = "voltage-ranges";
447 struct device *dev = host->parent;
448 u32 *voltage_ranges;
449 int num_ranges, i;
450 int ret;
451
452 if (!device_property_present(dev, prop)) {
453 dev_dbg(dev, "%s unspecified\n", prop);
454 return 0;
455 }
456
457 ret = device_property_count_u32(dev, prop);
458 if (ret < 0)
459 return ret;
460
461 num_ranges = ret / 2;
462 if (!num_ranges) {
463 dev_err(dev, "%s empty\n", prop);
464 return -EINVAL;
465 }
466
467 voltage_ranges = kcalloc(2 * num_ranges, sizeof(*voltage_ranges), GFP_KERNEL);
468 if (!voltage_ranges)
469 return -ENOMEM;
470
471 ret = device_property_read_u32_array(dev, prop, voltage_ranges, 2 * num_ranges);
472 if (ret) {
473 kfree(voltage_ranges);
474 return ret;
475 }
476
477 for (i = 0; i < num_ranges; i++) {
478 const int j = i * 2;
479 u32 ocr_mask;
480
481 ocr_mask = mmc_vddrange_to_ocrmask(voltage_ranges[j + 0],
482 voltage_ranges[j + 1]);
483 if (!ocr_mask) {
484 dev_err(dev, "range #%d in %s is invalid\n", i, prop);
485 kfree(voltage_ranges);
486 return -EINVAL;
487 }
488 *mask |= ocr_mask;
489 }
490
491 kfree(voltage_ranges);
492
493 return 1;
494}
495EXPORT_SYMBOL(mmc_of_parse_voltage);
496
497/**
498 * mmc_first_nonreserved_index() - get the first index that is not reserved
499 */
500static int mmc_first_nonreserved_index(void)
501{
502 int max;
503
504 max = of_alias_get_highest_id("mmc");
505 if (max < 0)
506 return 0;
507
508 return max + 1;
509}
510
511/**
512 * mmc_alloc_host - initialise the per-host structure.
513 * @extra: sizeof private data structure
514 * @dev: pointer to host device model structure
515 *
516 * Initialise the per-host structure.
517 */
518struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
519{
520 int index;
521 struct mmc_host *host;
522 int alias_id, min_idx, max_idx;
523
524 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
525 if (!host)
526 return NULL;
527
528 /* scanning will be enabled when we're ready */
529 host->rescan_disable = 1;
530
531 alias_id = of_alias_get_id(dev->of_node, "mmc");
532 if (alias_id >= 0) {
533 index = alias_id;
534 } else {
535 min_idx = mmc_first_nonreserved_index();
536 max_idx = 0;
537
538 index = ida_alloc_range(&mmc_host_ida, min_idx, max_idx - 1,
539 GFP_KERNEL);
540 if (index < 0) {
541 kfree(host);
542 return NULL;
543 }
544 }
545
546 host->index = index;
547
548 dev_set_name(&host->class_dev, "mmc%d", host->index);
549 host->ws = wakeup_source_register(NULL, dev_name(&host->class_dev));
550
551 host->parent = dev;
552 host->class_dev.parent = dev;
553 host->class_dev.class = &mmc_host_class;
554 device_initialize(&host->class_dev);
555 device_enable_async_suspend(&host->class_dev);
556
557 if (mmc_gpio_alloc(host)) {
558 put_device(&host->class_dev);
559 return NULL;
560 }
561
562 spin_lock_init(&host->lock);
563 init_waitqueue_head(&host->wq);
564 INIT_DELAYED_WORK(&host->detect, mmc_rescan);
565 INIT_WORK(&host->sdio_irq_work, sdio_irq_work);
566 timer_setup(&host->retune_timer, mmc_retune_timer, 0);
567
568 /*
569 * By default, hosts do not support SGIO or large requests.
570 * They have to set these according to their abilities.
571 */
572 host->max_segs = 1;
573 host->max_seg_size = PAGE_SIZE;
574
575 host->max_req_size = PAGE_SIZE;
576 host->max_blk_size = 512;
577 host->max_blk_count = PAGE_SIZE / 512;
578
579 host->fixed_drv_type = -EINVAL;
580 host->ios.power_delay_ms = 10;
581 host->ios.power_mode = MMC_POWER_UNDEFINED;
582
583 return host;
584}
585
586EXPORT_SYMBOL(mmc_alloc_host);
587
588static void devm_mmc_host_release(struct device *dev, void *res)
589{
590 mmc_free_host(*(struct mmc_host **)res);
591}
592
593struct mmc_host *devm_mmc_alloc_host(struct device *dev, int extra)
594{
595 struct mmc_host **dr, *host;
596
597 dr = devres_alloc(devm_mmc_host_release, sizeof(*dr), GFP_KERNEL);
598 if (!dr)
599 return NULL;
600
601 host = mmc_alloc_host(extra, dev);
602 if (!host) {
603 devres_free(dr);
604 return NULL;
605 }
606
607 *dr = host;
608 devres_add(dev, dr);
609
610 return host;
611}
612EXPORT_SYMBOL(devm_mmc_alloc_host);
613
614static int mmc_validate_host_caps(struct mmc_host *host)
615{
616 struct device *dev = host->parent;
617 u32 caps = host->caps, caps2 = host->caps2;
618
619 if (caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) {
620 dev_warn(dev, "missing ->enable_sdio_irq() ops\n");
621 return -EINVAL;
622 }
623
624 if (caps2 & (MMC_CAP2_HS400_ES | MMC_CAP2_HS400) &&
625 !(caps & MMC_CAP_8_BIT_DATA) && !(caps2 & MMC_CAP2_NO_MMC)) {
626 dev_warn(dev, "drop HS400 support since no 8-bit bus\n");
627 host->caps2 = caps2 & ~MMC_CAP2_HS400_ES & ~MMC_CAP2_HS400;
628 }
629
630 return 0;
631}
632
633/**
634 * mmc_add_host - initialise host hardware
635 * @host: mmc host
636 *
637 * Register the host with the driver model. The host must be
638 * prepared to start servicing requests before this function
639 * completes.
640 */
641int mmc_add_host(struct mmc_host *host)
642{
643 int err;
644
645 err = mmc_validate_host_caps(host);
646 if (err)
647 return err;
648
649 err = device_add(&host->class_dev);
650 if (err)
651 return err;
652
653 led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
654
655 mmc_add_host_debugfs(host);
656
657 mmc_start_host(host);
658 return 0;
659}
660
661EXPORT_SYMBOL(mmc_add_host);
662
663/**
664 * mmc_remove_host - remove host hardware
665 * @host: mmc host
666 *
667 * Unregister and remove all cards associated with this host,
668 * and power down the MMC bus. No new requests will be issued
669 * after this function has returned.
670 */
671void mmc_remove_host(struct mmc_host *host)
672{
673 mmc_stop_host(host);
674
675 mmc_remove_host_debugfs(host);
676
677 device_del(&host->class_dev);
678
679 led_trigger_unregister_simple(host->led);
680}
681
682EXPORT_SYMBOL(mmc_remove_host);
683
684/**
685 * mmc_free_host - free the host structure
686 * @host: mmc host
687 *
688 * Free the host once all references to it have been dropped.
689 */
690void mmc_free_host(struct mmc_host *host)
691{
692 cancel_delayed_work_sync(&host->detect);
693 mmc_pwrseq_free(host);
694 put_device(&host->class_dev);
695}
696
697EXPORT_SYMBOL(mmc_free_host);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/drivers/mmc/core/host.c
4 *
5 * Copyright (C) 2003 Russell King, All Rights Reserved.
6 * Copyright (C) 2007-2008 Pierre Ossman
7 * Copyright (C) 2010 Linus Walleij
8 *
9 * MMC host class device management
10 */
11
12#include <linux/device.h>
13#include <linux/err.h>
14#include <linux/idr.h>
15#include <linux/of.h>
16#include <linux/of_gpio.h>
17#include <linux/pagemap.h>
18#include <linux/pm_wakeup.h>
19#include <linux/export.h>
20#include <linux/leds.h>
21#include <linux/slab.h>
22
23#include <linux/mmc/host.h>
24#include <linux/mmc/card.h>
25#include <linux/mmc/slot-gpio.h>
26
27#include "core.h"
28#include "crypto.h"
29#include "host.h"
30#include "slot-gpio.h"
31#include "pwrseq.h"
32#include "sdio_ops.h"
33
34#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
35
36static DEFINE_IDA(mmc_host_ida);
37
38#ifdef CONFIG_PM_SLEEP
39static int mmc_host_class_prepare(struct device *dev)
40{
41 struct mmc_host *host = cls_dev_to_mmc_host(dev);
42
43 /*
44 * It's safe to access the bus_ops pointer, as both userspace and the
45 * workqueue for detecting cards are frozen at this point.
46 */
47 if (!host->bus_ops)
48 return 0;
49
50 /* Validate conditions for system suspend. */
51 if (host->bus_ops->pre_suspend)
52 return host->bus_ops->pre_suspend(host);
53
54 return 0;
55}
56
57static void mmc_host_class_complete(struct device *dev)
58{
59 struct mmc_host *host = cls_dev_to_mmc_host(dev);
60
61 _mmc_detect_change(host, 0, false);
62}
63
64static const struct dev_pm_ops mmc_host_class_dev_pm_ops = {
65 .prepare = mmc_host_class_prepare,
66 .complete = mmc_host_class_complete,
67};
68
69#define MMC_HOST_CLASS_DEV_PM_OPS (&mmc_host_class_dev_pm_ops)
70#else
71#define MMC_HOST_CLASS_DEV_PM_OPS NULL
72#endif
73
74static void mmc_host_classdev_release(struct device *dev)
75{
76 struct mmc_host *host = cls_dev_to_mmc_host(dev);
77 wakeup_source_unregister(host->ws);
78 if (of_alias_get_id(host->parent->of_node, "mmc") < 0)
79 ida_simple_remove(&mmc_host_ida, host->index);
80 kfree(host);
81}
82
83static int mmc_host_classdev_shutdown(struct device *dev)
84{
85 struct mmc_host *host = cls_dev_to_mmc_host(dev);
86
87 __mmc_stop_host(host);
88 return 0;
89}
90
91static struct class mmc_host_class = {
92 .name = "mmc_host",
93 .dev_release = mmc_host_classdev_release,
94 .shutdown_pre = mmc_host_classdev_shutdown,
95 .pm = MMC_HOST_CLASS_DEV_PM_OPS,
96};
97
98int mmc_register_host_class(void)
99{
100 return class_register(&mmc_host_class);
101}
102
103void mmc_unregister_host_class(void)
104{
105 class_unregister(&mmc_host_class);
106}
107
108/**
109 * mmc_retune_enable() - enter a transfer mode that requires retuning
110 * @host: host which should retune now
111 */
112void mmc_retune_enable(struct mmc_host *host)
113{
114 host->can_retune = 1;
115 if (host->retune_period)
116 mod_timer(&host->retune_timer,
117 jiffies + host->retune_period * HZ);
118}
119
120/*
121 * Pause re-tuning for a small set of operations. The pause begins after the
122 * next command.
123 */
124void mmc_retune_pause(struct mmc_host *host)
125{
126 if (!host->retune_paused) {
127 host->retune_paused = 1;
128 mmc_retune_hold(host);
129 }
130}
131EXPORT_SYMBOL(mmc_retune_pause);
132
133void mmc_retune_unpause(struct mmc_host *host)
134{
135 if (host->retune_paused) {
136 host->retune_paused = 0;
137 mmc_retune_release(host);
138 }
139}
140EXPORT_SYMBOL(mmc_retune_unpause);
141
142/**
143 * mmc_retune_disable() - exit a transfer mode that requires retuning
144 * @host: host which should not retune anymore
145 *
146 * It is not meant for temporarily preventing retuning!
147 */
148void mmc_retune_disable(struct mmc_host *host)
149{
150 mmc_retune_unpause(host);
151 host->can_retune = 0;
152 del_timer_sync(&host->retune_timer);
153 mmc_retune_clear(host);
154}
155
156void mmc_retune_timer_stop(struct mmc_host *host)
157{
158 del_timer_sync(&host->retune_timer);
159}
160EXPORT_SYMBOL(mmc_retune_timer_stop);
161
162void mmc_retune_hold(struct mmc_host *host)
163{
164 if (!host->hold_retune)
165 host->retune_now = 1;
166 host->hold_retune += 1;
167}
168
169void mmc_retune_release(struct mmc_host *host)
170{
171 if (host->hold_retune)
172 host->hold_retune -= 1;
173 else
174 WARN_ON(1);
175}
176EXPORT_SYMBOL(mmc_retune_release);
177
178int mmc_retune(struct mmc_host *host)
179{
180 bool return_to_hs400 = false;
181 int err;
182
183 if (host->retune_now)
184 host->retune_now = 0;
185 else
186 return 0;
187
188 if (!host->need_retune || host->doing_retune || !host->card)
189 return 0;
190
191 host->need_retune = 0;
192
193 host->doing_retune = 1;
194
195 if (host->ios.timing == MMC_TIMING_MMC_HS400) {
196 err = mmc_hs400_to_hs200(host->card);
197 if (err)
198 goto out;
199
200 return_to_hs400 = true;
201 }
202
203 err = mmc_execute_tuning(host->card);
204 if (err)
205 goto out;
206
207 if (return_to_hs400)
208 err = mmc_hs200_to_hs400(host->card);
209out:
210 host->doing_retune = 0;
211
212 return err;
213}
214
215static void mmc_retune_timer(struct timer_list *t)
216{
217 struct mmc_host *host = from_timer(host, t, retune_timer);
218
219 mmc_retune_needed(host);
220}
221
222static void mmc_of_parse_timing_phase(struct device *dev, const char *prop,
223 struct mmc_clk_phase *phase)
224{
225 int degrees[2] = {0};
226 int rc;
227
228 rc = device_property_read_u32_array(dev, prop, degrees, 2);
229 phase->valid = !rc;
230 if (phase->valid) {
231 phase->in_deg = degrees[0];
232 phase->out_deg = degrees[1];
233 }
234}
235
236void
237mmc_of_parse_clk_phase(struct mmc_host *host, struct mmc_clk_phase_map *map)
238{
239 struct device *dev = host->parent;
240
241 mmc_of_parse_timing_phase(dev, "clk-phase-legacy",
242 &map->phase[MMC_TIMING_LEGACY]);
243 mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs",
244 &map->phase[MMC_TIMING_MMC_HS]);
245 mmc_of_parse_timing_phase(dev, "clk-phase-sd-hs",
246 &map->phase[MMC_TIMING_SD_HS]);
247 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr12",
248 &map->phase[MMC_TIMING_UHS_SDR12]);
249 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr25",
250 &map->phase[MMC_TIMING_UHS_SDR25]);
251 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr50",
252 &map->phase[MMC_TIMING_UHS_SDR50]);
253 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr104",
254 &map->phase[MMC_TIMING_UHS_SDR104]);
255 mmc_of_parse_timing_phase(dev, "clk-phase-uhs-ddr50",
256 &map->phase[MMC_TIMING_UHS_DDR50]);
257 mmc_of_parse_timing_phase(dev, "clk-phase-mmc-ddr52",
258 &map->phase[MMC_TIMING_MMC_DDR52]);
259 mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs200",
260 &map->phase[MMC_TIMING_MMC_HS200]);
261 mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs400",
262 &map->phase[MMC_TIMING_MMC_HS400]);
263}
264EXPORT_SYMBOL(mmc_of_parse_clk_phase);
265
266/**
267 * mmc_of_parse() - parse host's device properties
268 * @host: host whose properties should be parsed.
269 *
270 * To keep the rest of the MMC subsystem unaware of whether DT has been
271 * used to instantiate and configure this host instance or not, we
272 * parse the properties and set respective generic mmc-host flags and
273 * parameters.
274 */
275int mmc_of_parse(struct mmc_host *host)
276{
277 struct device *dev = host->parent;
278 u32 bus_width, drv_type, cd_debounce_delay_ms;
279 int ret;
280
281 if (!dev || !dev_fwnode(dev))
282 return 0;
283
284 /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
285 if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) {
286 dev_dbg(host->parent,
287 "\"bus-width\" property is missing, assuming 1 bit.\n");
288 bus_width = 1;
289 }
290
291 switch (bus_width) {
292 case 8:
293 host->caps |= MMC_CAP_8_BIT_DATA;
294 fallthrough; /* Hosts capable of 8-bit can also do 4 bits */
295 case 4:
296 host->caps |= MMC_CAP_4_BIT_DATA;
297 break;
298 case 1:
299 break;
300 default:
301 dev_err(host->parent,
302 "Invalid \"bus-width\" value %u!\n", bus_width);
303 return -EINVAL;
304 }
305
306 /* f_max is obtained from the optional "max-frequency" property */
307 device_property_read_u32(dev, "max-frequency", &host->f_max);
308
309 /*
310 * Configure CD and WP pins. They are both by default active low to
311 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
312 * mmc-gpio helpers are used to attach, configure and use them. If
313 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
314 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
315 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
316 * is set. If the "non-removable" property is found, the
317 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
318 * configuration is performed.
319 */
320
321 /* Parse Card Detection */
322
323 if (device_property_read_bool(dev, "non-removable")) {
324 host->caps |= MMC_CAP_NONREMOVABLE;
325 } else {
326 if (device_property_read_bool(dev, "cd-inverted"))
327 host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
328
329 if (device_property_read_u32(dev, "cd-debounce-delay-ms",
330 &cd_debounce_delay_ms))
331 cd_debounce_delay_ms = 200;
332
333 if (device_property_read_bool(dev, "broken-cd"))
334 host->caps |= MMC_CAP_NEEDS_POLL;
335
336 ret = mmc_gpiod_request_cd(host, "cd", 0, false,
337 cd_debounce_delay_ms * 1000);
338 if (!ret)
339 dev_info(host->parent, "Got CD GPIO\n");
340 else if (ret != -ENOENT && ret != -ENOSYS)
341 return ret;
342 }
343
344 /* Parse Write Protection */
345
346 if (device_property_read_bool(dev, "wp-inverted"))
347 host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
348
349 ret = mmc_gpiod_request_ro(host, "wp", 0, 0);
350 if (!ret)
351 dev_info(host->parent, "Got WP GPIO\n");
352 else if (ret != -ENOENT && ret != -ENOSYS)
353 return ret;
354
355 if (device_property_read_bool(dev, "disable-wp"))
356 host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
357
358 if (device_property_read_bool(dev, "cap-sd-highspeed"))
359 host->caps |= MMC_CAP_SD_HIGHSPEED;
360 if (device_property_read_bool(dev, "cap-mmc-highspeed"))
361 host->caps |= MMC_CAP_MMC_HIGHSPEED;
362 if (device_property_read_bool(dev, "sd-uhs-sdr12"))
363 host->caps |= MMC_CAP_UHS_SDR12;
364 if (device_property_read_bool(dev, "sd-uhs-sdr25"))
365 host->caps |= MMC_CAP_UHS_SDR25;
366 if (device_property_read_bool(dev, "sd-uhs-sdr50"))
367 host->caps |= MMC_CAP_UHS_SDR50;
368 if (device_property_read_bool(dev, "sd-uhs-sdr104"))
369 host->caps |= MMC_CAP_UHS_SDR104;
370 if (device_property_read_bool(dev, "sd-uhs-ddr50"))
371 host->caps |= MMC_CAP_UHS_DDR50;
372 if (device_property_read_bool(dev, "cap-power-off-card"))
373 host->caps |= MMC_CAP_POWER_OFF_CARD;
374 if (device_property_read_bool(dev, "cap-mmc-hw-reset"))
375 host->caps |= MMC_CAP_HW_RESET;
376 if (device_property_read_bool(dev, "cap-sdio-irq"))
377 host->caps |= MMC_CAP_SDIO_IRQ;
378 if (device_property_read_bool(dev, "full-pwr-cycle"))
379 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
380 if (device_property_read_bool(dev, "full-pwr-cycle-in-suspend"))
381 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND;
382 if (device_property_read_bool(dev, "keep-power-in-suspend"))
383 host->pm_caps |= MMC_PM_KEEP_POWER;
384 if (device_property_read_bool(dev, "wakeup-source") ||
385 device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
386 host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
387 if (device_property_read_bool(dev, "mmc-ddr-3_3v"))
388 host->caps |= MMC_CAP_3_3V_DDR;
389 if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
390 host->caps |= MMC_CAP_1_8V_DDR;
391 if (device_property_read_bool(dev, "mmc-ddr-1_2v"))
392 host->caps |= MMC_CAP_1_2V_DDR;
393 if (device_property_read_bool(dev, "mmc-hs200-1_8v"))
394 host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
395 if (device_property_read_bool(dev, "mmc-hs200-1_2v"))
396 host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
397 if (device_property_read_bool(dev, "mmc-hs400-1_8v"))
398 host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
399 if (device_property_read_bool(dev, "mmc-hs400-1_2v"))
400 host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
401 if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe"))
402 host->caps2 |= MMC_CAP2_HS400_ES;
403 if (device_property_read_bool(dev, "no-sdio"))
404 host->caps2 |= MMC_CAP2_NO_SDIO;
405 if (device_property_read_bool(dev, "no-sd"))
406 host->caps2 |= MMC_CAP2_NO_SD;
407 if (device_property_read_bool(dev, "no-mmc"))
408 host->caps2 |= MMC_CAP2_NO_MMC;
409 if (device_property_read_bool(dev, "no-mmc-hs400"))
410 host->caps2 &= ~(MMC_CAP2_HS400_1_8V | MMC_CAP2_HS400_1_2V |
411 MMC_CAP2_HS400_ES);
412
413 /* Must be after "non-removable" check */
414 if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) {
415 if (host->caps & MMC_CAP_NONREMOVABLE)
416 host->fixed_drv_type = drv_type;
417 else
418 dev_err(host->parent,
419 "can't use fixed driver type, media is removable\n");
420 }
421
422 host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr);
423 if (host->dsr_req && (host->dsr & ~0xffff)) {
424 dev_err(host->parent,
425 "device tree specified broken value for DSR: 0x%x, ignoring\n",
426 host->dsr);
427 host->dsr_req = 0;
428 }
429
430 device_property_read_u32(dev, "post-power-on-delay-ms",
431 &host->ios.power_delay_ms);
432
433 return mmc_pwrseq_alloc(host);
434}
435
436EXPORT_SYMBOL(mmc_of_parse);
437
438/**
439 * mmc_of_parse_voltage - return mask of supported voltages
440 * @host: host whose properties should be parsed.
441 * @mask: mask of voltages available for MMC/SD/SDIO
442 *
443 * Parse the "voltage-ranges" property, returning zero if it is not
444 * found, negative errno if the voltage-range specification is invalid,
445 * or one if the voltage-range is specified and successfully parsed.
446 */
447int mmc_of_parse_voltage(struct mmc_host *host, u32 *mask)
448{
449 const char *prop = "voltage-ranges";
450 struct device *dev = host->parent;
451 u32 *voltage_ranges;
452 int num_ranges, i;
453 int ret;
454
455 if (!device_property_present(dev, prop)) {
456 dev_dbg(dev, "%s unspecified\n", prop);
457 return 0;
458 }
459
460 ret = device_property_count_u32(dev, prop);
461 if (ret < 0)
462 return ret;
463
464 num_ranges = ret / 2;
465 if (!num_ranges) {
466 dev_err(dev, "%s empty\n", prop);
467 return -EINVAL;
468 }
469
470 voltage_ranges = kcalloc(2 * num_ranges, sizeof(*voltage_ranges), GFP_KERNEL);
471 if (!voltage_ranges)
472 return -ENOMEM;
473
474 ret = device_property_read_u32_array(dev, prop, voltage_ranges, 2 * num_ranges);
475 if (ret) {
476 kfree(voltage_ranges);
477 return ret;
478 }
479
480 for (i = 0; i < num_ranges; i++) {
481 const int j = i * 2;
482 u32 ocr_mask;
483
484 ocr_mask = mmc_vddrange_to_ocrmask(voltage_ranges[j + 0],
485 voltage_ranges[j + 1]);
486 if (!ocr_mask) {
487 dev_err(dev, "range #%d in %s is invalid\n", i, prop);
488 kfree(voltage_ranges);
489 return -EINVAL;
490 }
491 *mask |= ocr_mask;
492 }
493
494 kfree(voltage_ranges);
495
496 return 1;
497}
498EXPORT_SYMBOL(mmc_of_parse_voltage);
499
500/**
501 * mmc_first_nonreserved_index() - get the first index that is not reserved
502 */
503static int mmc_first_nonreserved_index(void)
504{
505 int max;
506
507 max = of_alias_get_highest_id("mmc");
508 if (max < 0)
509 return 0;
510
511 return max + 1;
512}
513
514/**
515 * mmc_alloc_host - initialise the per-host structure.
516 * @extra: sizeof private data structure
517 * @dev: pointer to host device model structure
518 *
519 * Initialise the per-host structure.
520 */
521struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
522{
523 int index;
524 struct mmc_host *host;
525 int alias_id, min_idx, max_idx;
526
527 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
528 if (!host)
529 return NULL;
530
531 /* scanning will be enabled when we're ready */
532 host->rescan_disable = 1;
533
534 alias_id = of_alias_get_id(dev->of_node, "mmc");
535 if (alias_id >= 0) {
536 index = alias_id;
537 } else {
538 min_idx = mmc_first_nonreserved_index();
539 max_idx = 0;
540
541 index = ida_simple_get(&mmc_host_ida, min_idx, max_idx, GFP_KERNEL);
542 if (index < 0) {
543 kfree(host);
544 return NULL;
545 }
546 }
547
548 host->index = index;
549
550 dev_set_name(&host->class_dev, "mmc%d", host->index);
551 host->ws = wakeup_source_register(NULL, dev_name(&host->class_dev));
552
553 host->parent = dev;
554 host->class_dev.parent = dev;
555 host->class_dev.class = &mmc_host_class;
556 device_initialize(&host->class_dev);
557 device_enable_async_suspend(&host->class_dev);
558
559 if (mmc_gpio_alloc(host)) {
560 put_device(&host->class_dev);
561 return NULL;
562 }
563
564 spin_lock_init(&host->lock);
565 init_waitqueue_head(&host->wq);
566 INIT_DELAYED_WORK(&host->detect, mmc_rescan);
567 INIT_WORK(&host->sdio_irq_work, sdio_irq_work);
568 timer_setup(&host->retune_timer, mmc_retune_timer, 0);
569
570 /*
571 * By default, hosts do not support SGIO or large requests.
572 * They have to set these according to their abilities.
573 */
574 host->max_segs = 1;
575 host->max_seg_size = PAGE_SIZE;
576
577 host->max_req_size = PAGE_SIZE;
578 host->max_blk_size = 512;
579 host->max_blk_count = PAGE_SIZE / 512;
580
581 host->fixed_drv_type = -EINVAL;
582 host->ios.power_delay_ms = 10;
583 host->ios.power_mode = MMC_POWER_UNDEFINED;
584
585 return host;
586}
587
588EXPORT_SYMBOL(mmc_alloc_host);
589
590static void devm_mmc_host_release(struct device *dev, void *res)
591{
592 mmc_free_host(*(struct mmc_host **)res);
593}
594
595struct mmc_host *devm_mmc_alloc_host(struct device *dev, int extra)
596{
597 struct mmc_host **dr, *host;
598
599 dr = devres_alloc(devm_mmc_host_release, sizeof(*dr), GFP_KERNEL);
600 if (!dr)
601 return NULL;
602
603 host = mmc_alloc_host(extra, dev);
604 if (!host) {
605 devres_free(dr);
606 return NULL;
607 }
608
609 *dr = host;
610 devres_add(dev, dr);
611
612 return host;
613}
614EXPORT_SYMBOL(devm_mmc_alloc_host);
615
616static int mmc_validate_host_caps(struct mmc_host *host)
617{
618 struct device *dev = host->parent;
619 u32 caps = host->caps, caps2 = host->caps2;
620
621 if (caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) {
622 dev_warn(dev, "missing ->enable_sdio_irq() ops\n");
623 return -EINVAL;
624 }
625
626 if (caps2 & (MMC_CAP2_HS400_ES | MMC_CAP2_HS400) &&
627 !(caps & MMC_CAP_8_BIT_DATA) && !(caps2 & MMC_CAP2_NO_MMC)) {
628 dev_warn(dev, "drop HS400 support since no 8-bit bus\n");
629 host->caps2 = caps2 & ~MMC_CAP2_HS400_ES & ~MMC_CAP2_HS400;
630 }
631
632 return 0;
633}
634
635/**
636 * mmc_add_host - initialise host hardware
637 * @host: mmc host
638 *
639 * Register the host with the driver model. The host must be
640 * prepared to start servicing requests before this function
641 * completes.
642 */
643int mmc_add_host(struct mmc_host *host)
644{
645 int err;
646
647 err = mmc_validate_host_caps(host);
648 if (err)
649 return err;
650
651 err = device_add(&host->class_dev);
652 if (err)
653 return err;
654
655 led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
656
657 mmc_add_host_debugfs(host);
658
659 mmc_start_host(host);
660 return 0;
661}
662
663EXPORT_SYMBOL(mmc_add_host);
664
665/**
666 * mmc_remove_host - remove host hardware
667 * @host: mmc host
668 *
669 * Unregister and remove all cards associated with this host,
670 * and power down the MMC bus. No new requests will be issued
671 * after this function has returned.
672 */
673void mmc_remove_host(struct mmc_host *host)
674{
675 mmc_stop_host(host);
676
677 mmc_remove_host_debugfs(host);
678
679 device_del(&host->class_dev);
680
681 led_trigger_unregister_simple(host->led);
682}
683
684EXPORT_SYMBOL(mmc_remove_host);
685
686/**
687 * mmc_free_host - free the host structure
688 * @host: mmc host
689 *
690 * Free the host once all references to it have been dropped.
691 */
692void mmc_free_host(struct mmc_host *host)
693{
694 cancel_delayed_work_sync(&host->detect);
695 mmc_pwrseq_free(host);
696 put_device(&host->class_dev);
697}
698
699EXPORT_SYMBOL(mmc_free_host);