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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/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 
36 static DEFINE_IDA(mmc_host_ida);
37 
38 #ifdef CONFIG_PM_SLEEP
mmc_host_class_prepare(struct device * dev)39 static 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 
mmc_host_class_complete(struct device * dev)57 static 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 
64 static 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 
mmc_host_classdev_release(struct device * dev)74 static 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 
mmc_host_classdev_shutdown(struct device * dev)83 static 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 
91 static 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 
mmc_register_host_class(void)98 int mmc_register_host_class(void)
99 {
100 	return class_register(&mmc_host_class);
101 }
102 
mmc_unregister_host_class(void)103 void mmc_unregister_host_class(void)
104 {
105 	class_unregister(&mmc_host_class);
106 }
107 
mmc_retune_enable(struct mmc_host * host)108 void mmc_retune_enable(struct mmc_host *host)
109 {
110 	host->can_retune = 1;
111 	if (host->retune_period)
112 		mod_timer(&host->retune_timer,
113 			  jiffies + host->retune_period * HZ);
114 }
115 
116 /*
117  * Pause re-tuning for a small set of operations.  The pause begins after the
118  * next command and after first doing re-tuning.
119  */
mmc_retune_pause(struct mmc_host * host)120 void mmc_retune_pause(struct mmc_host *host)
121 {
122 	if (!host->retune_paused) {
123 		host->retune_paused = 1;
124 		mmc_retune_needed(host);
125 		mmc_retune_hold(host);
126 	}
127 }
128 EXPORT_SYMBOL(mmc_retune_pause);
129 
mmc_retune_unpause(struct mmc_host * host)130 void mmc_retune_unpause(struct mmc_host *host)
131 {
132 	if (host->retune_paused) {
133 		host->retune_paused = 0;
134 		mmc_retune_release(host);
135 	}
136 }
137 EXPORT_SYMBOL(mmc_retune_unpause);
138 
mmc_retune_disable(struct mmc_host * host)139 void mmc_retune_disable(struct mmc_host *host)
140 {
141 	mmc_retune_unpause(host);
142 	host->can_retune = 0;
143 	del_timer_sync(&host->retune_timer);
144 	host->retune_now = 0;
145 	host->need_retune = 0;
146 }
147 
mmc_retune_timer_stop(struct mmc_host * host)148 void mmc_retune_timer_stop(struct mmc_host *host)
149 {
150 	del_timer_sync(&host->retune_timer);
151 }
152 EXPORT_SYMBOL(mmc_retune_timer_stop);
153 
mmc_retune_hold(struct mmc_host * host)154 void mmc_retune_hold(struct mmc_host *host)
155 {
156 	if (!host->hold_retune)
157 		host->retune_now = 1;
158 	host->hold_retune += 1;
159 }
160 
mmc_retune_release(struct mmc_host * host)161 void mmc_retune_release(struct mmc_host *host)
162 {
163 	if (host->hold_retune)
164 		host->hold_retune -= 1;
165 	else
166 		WARN_ON(1);
167 }
168 EXPORT_SYMBOL(mmc_retune_release);
169 
mmc_retune(struct mmc_host * host)170 int mmc_retune(struct mmc_host *host)
171 {
172 	bool return_to_hs400 = false;
173 	int err;
174 
175 	if (host->retune_now)
176 		host->retune_now = 0;
177 	else
178 		return 0;
179 
180 	if (!host->need_retune || host->doing_retune || !host->card)
181 		return 0;
182 
183 	host->need_retune = 0;
184 
185 	host->doing_retune = 1;
186 
187 	if (host->ios.timing == MMC_TIMING_MMC_HS400) {
188 		err = mmc_hs400_to_hs200(host->card);
189 		if (err)
190 			goto out;
191 
192 		return_to_hs400 = true;
193 	}
194 
195 	err = mmc_execute_tuning(host->card);
196 	if (err)
197 		goto out;
198 
199 	if (return_to_hs400)
200 		err = mmc_hs200_to_hs400(host->card);
201 out:
202 	host->doing_retune = 0;
203 
204 	return err;
205 }
206 
mmc_retune_timer(struct timer_list * t)207 static void mmc_retune_timer(struct timer_list *t)
208 {
209 	struct mmc_host *host = from_timer(host, t, retune_timer);
210 
211 	mmc_retune_needed(host);
212 }
213 
214 /**
215  *	mmc_of_parse() - parse host's device-tree node
216  *	@host: host whose node should be parsed.
217  *
218  * To keep the rest of the MMC subsystem unaware of whether DT has been
219  * used to to instantiate and configure this host instance or not, we
220  * parse the properties and set respective generic mmc-host flags and
221  * parameters.
222  */
mmc_of_parse(struct mmc_host * host)223 int mmc_of_parse(struct mmc_host *host)
224 {
225 	struct device *dev = host->parent;
226 	u32 bus_width, drv_type, cd_debounce_delay_ms;
227 	int ret;
228 
229 	if (!dev || !dev_fwnode(dev))
230 		return 0;
231 
232 	/* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
233 	if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) {
234 		dev_dbg(host->parent,
235 			"\"bus-width\" property is missing, assuming 1 bit.\n");
236 		bus_width = 1;
237 	}
238 
239 	switch (bus_width) {
240 	case 8:
241 		host->caps |= MMC_CAP_8_BIT_DATA;
242 		fallthrough;	/* Hosts capable of 8-bit can also do 4 bits */
243 	case 4:
244 		host->caps |= MMC_CAP_4_BIT_DATA;
245 		break;
246 	case 1:
247 		break;
248 	default:
249 		dev_err(host->parent,
250 			"Invalid \"bus-width\" value %u!\n", bus_width);
251 		return -EINVAL;
252 	}
253 
254 	/* f_max is obtained from the optional "max-frequency" property */
255 	device_property_read_u32(dev, "max-frequency", &host->f_max);
256 
257 	/*
258 	 * Configure CD and WP pins. They are both by default active low to
259 	 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
260 	 * mmc-gpio helpers are used to attach, configure and use them. If
261 	 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
262 	 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
263 	 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
264 	 * is set. If the "non-removable" property is found, the
265 	 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
266 	 * configuration is performed.
267 	 */
268 
269 	/* Parse Card Detection */
270 
271 	if (device_property_read_bool(dev, "non-removable")) {
272 		host->caps |= MMC_CAP_NONREMOVABLE;
273 	} else {
274 		if (device_property_read_bool(dev, "cd-inverted"))
275 			host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
276 
277 		if (device_property_read_u32(dev, "cd-debounce-delay-ms",
278 					     &cd_debounce_delay_ms))
279 			cd_debounce_delay_ms = 200;
280 
281 		if (device_property_read_bool(dev, "broken-cd"))
282 			host->caps |= MMC_CAP_NEEDS_POLL;
283 
284 		ret = mmc_gpiod_request_cd(host, "cd", 0, false,
285 					   cd_debounce_delay_ms * 1000);
286 		if (!ret)
287 			dev_info(host->parent, "Got CD GPIO\n");
288 		else if (ret != -ENOENT && ret != -ENOSYS)
289 			return ret;
290 	}
291 
292 	/* Parse Write Protection */
293 
294 	if (device_property_read_bool(dev, "wp-inverted"))
295 		host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
296 
297 	ret = mmc_gpiod_request_ro(host, "wp", 0, 0);
298 	if (!ret)
299 		dev_info(host->parent, "Got WP GPIO\n");
300 	else if (ret != -ENOENT && ret != -ENOSYS)
301 		return ret;
302 
303 	if (device_property_read_bool(dev, "disable-wp"))
304 		host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
305 
306 	if (device_property_read_bool(dev, "cap-sd-highspeed"))
307 		host->caps |= MMC_CAP_SD_HIGHSPEED;
308 	if (device_property_read_bool(dev, "cap-mmc-highspeed"))
309 		host->caps |= MMC_CAP_MMC_HIGHSPEED;
310 	if (device_property_read_bool(dev, "sd-uhs-sdr12"))
311 		host->caps |= MMC_CAP_UHS_SDR12;
312 	if (device_property_read_bool(dev, "sd-uhs-sdr25"))
313 		host->caps |= MMC_CAP_UHS_SDR25;
314 	if (device_property_read_bool(dev, "sd-uhs-sdr50"))
315 		host->caps |= MMC_CAP_UHS_SDR50;
316 	if (device_property_read_bool(dev, "sd-uhs-sdr104"))
317 		host->caps |= MMC_CAP_UHS_SDR104;
318 	if (device_property_read_bool(dev, "sd-uhs-ddr50"))
319 		host->caps |= MMC_CAP_UHS_DDR50;
320 	if (device_property_read_bool(dev, "cap-power-off-card"))
321 		host->caps |= MMC_CAP_POWER_OFF_CARD;
322 	if (device_property_read_bool(dev, "cap-mmc-hw-reset"))
323 		host->caps |= MMC_CAP_HW_RESET;
324 	if (device_property_read_bool(dev, "cap-sdio-irq"))
325 		host->caps |= MMC_CAP_SDIO_IRQ;
326 	if (device_property_read_bool(dev, "full-pwr-cycle"))
327 		host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
328 	if (device_property_read_bool(dev, "full-pwr-cycle-in-suspend"))
329 		host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND;
330 	if (device_property_read_bool(dev, "keep-power-in-suspend"))
331 		host->pm_caps |= MMC_PM_KEEP_POWER;
332 	if (device_property_read_bool(dev, "wakeup-source") ||
333 	    device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
334 		host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
335 	if (device_property_read_bool(dev, "mmc-ddr-3_3v"))
336 		host->caps |= MMC_CAP_3_3V_DDR;
337 	if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
338 		host->caps |= MMC_CAP_1_8V_DDR;
339 	if (device_property_read_bool(dev, "mmc-ddr-1_2v"))
340 		host->caps |= MMC_CAP_1_2V_DDR;
341 	if (device_property_read_bool(dev, "mmc-hs200-1_8v"))
342 		host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
343 	if (device_property_read_bool(dev, "mmc-hs200-1_2v"))
344 		host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
345 	if (device_property_read_bool(dev, "mmc-hs400-1_8v"))
346 		host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
347 	if (device_property_read_bool(dev, "mmc-hs400-1_2v"))
348 		host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
349 	if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe"))
350 		host->caps2 |= MMC_CAP2_HS400_ES;
351 	if (device_property_read_bool(dev, "no-sdio"))
352 		host->caps2 |= MMC_CAP2_NO_SDIO;
353 	if (device_property_read_bool(dev, "no-sd"))
354 		host->caps2 |= MMC_CAP2_NO_SD;
355 	if (device_property_read_bool(dev, "no-mmc"))
356 		host->caps2 |= MMC_CAP2_NO_MMC;
357 
358 	/* Must be after "non-removable" check */
359 	if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) {
360 		if (host->caps & MMC_CAP_NONREMOVABLE)
361 			host->fixed_drv_type = drv_type;
362 		else
363 			dev_err(host->parent,
364 				"can't use fixed driver type, media is removable\n");
365 	}
366 
367 	host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr);
368 	if (host->dsr_req && (host->dsr & ~0xffff)) {
369 		dev_err(host->parent,
370 			"device tree specified broken value for DSR: 0x%x, ignoring\n",
371 			host->dsr);
372 		host->dsr_req = 0;
373 	}
374 
375 	device_property_read_u32(dev, "post-power-on-delay-ms",
376 				 &host->ios.power_delay_ms);
377 
378 	return mmc_pwrseq_alloc(host);
379 }
380 
381 EXPORT_SYMBOL(mmc_of_parse);
382 
383 /**
384  * mmc_of_parse_voltage - return mask of supported voltages
385  * @np: The device node need to be parsed.
386  * @mask: mask of voltages available for MMC/SD/SDIO
387  *
388  * Parse the "voltage-ranges" DT property, returning zero if it is not
389  * found, negative errno if the voltage-range specification is invalid,
390  * or one if the voltage-range is specified and successfully parsed.
391  */
mmc_of_parse_voltage(struct device_node * np,u32 * mask)392 int mmc_of_parse_voltage(struct device_node *np, u32 *mask)
393 {
394 	const u32 *voltage_ranges;
395 	int num_ranges, i;
396 
397 	voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
398 	if (!voltage_ranges) {
399 		pr_debug("%pOF: voltage-ranges unspecified\n", np);
400 		return 0;
401 	}
402 	num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
403 	if (!num_ranges) {
404 		pr_err("%pOF: voltage-ranges empty\n", np);
405 		return -EINVAL;
406 	}
407 
408 	for (i = 0; i < num_ranges; i++) {
409 		const int j = i * 2;
410 		u32 ocr_mask;
411 
412 		ocr_mask = mmc_vddrange_to_ocrmask(
413 				be32_to_cpu(voltage_ranges[j]),
414 				be32_to_cpu(voltage_ranges[j + 1]));
415 		if (!ocr_mask) {
416 			pr_err("%pOF: voltage-range #%d is invalid\n",
417 				np, i);
418 			return -EINVAL;
419 		}
420 		*mask |= ocr_mask;
421 	}
422 
423 	return 1;
424 }
425 EXPORT_SYMBOL(mmc_of_parse_voltage);
426 
427 /**
428  * mmc_first_nonreserved_index() - get the first index that is not reserved
429  */
mmc_first_nonreserved_index(void)430 static int mmc_first_nonreserved_index(void)
431 {
432 	int max;
433 
434 	max = of_alias_get_highest_id("mmc");
435 	if (max < 0)
436 		return 0;
437 
438 	return max + 1;
439 }
440 
441 /**
442  *	mmc_alloc_host - initialise the per-host structure.
443  *	@extra: sizeof private data structure
444  *	@dev: pointer to host device model structure
445  *
446  *	Initialise the per-host structure.
447  */
mmc_alloc_host(int extra,struct device * dev)448 struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
449 {
450 	int index;
451 	struct mmc_host *host;
452 	int alias_id, min_idx, max_idx;
453 
454 	host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
455 	if (!host)
456 		return NULL;
457 
458 	/* scanning will be enabled when we're ready */
459 	host->rescan_disable = 1;
460 
461 	alias_id = of_alias_get_id(dev->of_node, "mmc");
462 	if (alias_id >= 0) {
463 		index = alias_id;
464 	} else {
465 		min_idx = mmc_first_nonreserved_index();
466 		max_idx = 0;
467 
468 		index = ida_simple_get(&mmc_host_ida, min_idx, max_idx, GFP_KERNEL);
469 		if (index < 0) {
470 			kfree(host);
471 			return NULL;
472 		}
473 	}
474 
475 	host->index = index;
476 
477 	dev_set_name(&host->class_dev, "mmc%d", host->index);
478 	host->ws = wakeup_source_register(NULL, dev_name(&host->class_dev));
479 
480 	host->parent = dev;
481 	host->class_dev.parent = dev;
482 	host->class_dev.class = &mmc_host_class;
483 	device_initialize(&host->class_dev);
484 	device_enable_async_suspend(&host->class_dev);
485 
486 	if (mmc_gpio_alloc(host)) {
487 		put_device(&host->class_dev);
488 		return NULL;
489 	}
490 
491 	spin_lock_init(&host->lock);
492 	init_waitqueue_head(&host->wq);
493 	INIT_DELAYED_WORK(&host->detect, mmc_rescan);
494 	INIT_DELAYED_WORK(&host->sdio_irq_work, sdio_irq_work);
495 	timer_setup(&host->retune_timer, mmc_retune_timer, 0);
496 
497 	/*
498 	 * By default, hosts do not support SGIO or large requests.
499 	 * They have to set these according to their abilities.
500 	 */
501 	host->max_segs = 1;
502 	host->max_seg_size = PAGE_SIZE;
503 
504 	host->max_req_size = PAGE_SIZE;
505 	host->max_blk_size = 512;
506 	host->max_blk_count = PAGE_SIZE / 512;
507 
508 	host->fixed_drv_type = -EINVAL;
509 	host->ios.power_delay_ms = 10;
510 	host->ios.power_mode = MMC_POWER_UNDEFINED;
511 
512 	return host;
513 }
514 
515 EXPORT_SYMBOL(mmc_alloc_host);
516 
devm_mmc_host_release(struct device * dev,void * res)517 static void devm_mmc_host_release(struct device *dev, void *res)
518 {
519 	mmc_free_host(*(struct mmc_host **)res);
520 }
521 
devm_mmc_alloc_host(struct device * dev,int extra)522 struct mmc_host *devm_mmc_alloc_host(struct device *dev, int extra)
523 {
524 	struct mmc_host **dr, *host;
525 
526 	dr = devres_alloc(devm_mmc_host_release, sizeof(*dr), GFP_KERNEL);
527 	if (!dr)
528 		return ERR_PTR(-ENOMEM);
529 
530 	host = mmc_alloc_host(extra, dev);
531 	if (IS_ERR(host)) {
532 		devres_free(dr);
533 		return host;
534 	}
535 
536 	*dr = host;
537 	devres_add(dev, dr);
538 
539 	return host;
540 }
541 EXPORT_SYMBOL(devm_mmc_alloc_host);
542 
mmc_validate_host_caps(struct mmc_host * host)543 static int mmc_validate_host_caps(struct mmc_host *host)
544 {
545 	if (host->caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) {
546 		dev_warn(host->parent, "missing ->enable_sdio_irq() ops\n");
547 		return -EINVAL;
548 	}
549 
550 	return 0;
551 }
552 
553 /**
554  *	mmc_add_host - initialise host hardware
555  *	@host: mmc host
556  *
557  *	Register the host with the driver model. The host must be
558  *	prepared to start servicing requests before this function
559  *	completes.
560  */
mmc_add_host(struct mmc_host * host)561 int mmc_add_host(struct mmc_host *host)
562 {
563 	int err;
564 
565 	err = mmc_validate_host_caps(host);
566 	if (err)
567 		return err;
568 
569 	err = device_add(&host->class_dev);
570 	if (err)
571 		return err;
572 
573 	led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
574 
575 #ifdef CONFIG_DEBUG_FS
576 	mmc_add_host_debugfs(host);
577 #endif
578 
579 	mmc_start_host(host);
580 	return 0;
581 }
582 
583 EXPORT_SYMBOL(mmc_add_host);
584 
585 /**
586  *	mmc_remove_host - remove host hardware
587  *	@host: mmc host
588  *
589  *	Unregister and remove all cards associated with this host,
590  *	and power down the MMC bus. No new requests will be issued
591  *	after this function has returned.
592  */
mmc_remove_host(struct mmc_host * host)593 void mmc_remove_host(struct mmc_host *host)
594 {
595 	mmc_stop_host(host);
596 
597 #ifdef CONFIG_DEBUG_FS
598 	mmc_remove_host_debugfs(host);
599 #endif
600 
601 	device_del(&host->class_dev);
602 
603 	led_trigger_unregister_simple(host->led);
604 }
605 
606 EXPORT_SYMBOL(mmc_remove_host);
607 
608 /**
609  *	mmc_free_host - free the host structure
610  *	@host: mmc host
611  *
612  *	Free the host once all references to it have been dropped.
613  */
mmc_free_host(struct mmc_host * host)614 void mmc_free_host(struct mmc_host *host)
615 {
616 	cancel_delayed_work_sync(&host->detect);
617 	mmc_pwrseq_free(host);
618 	put_device(&host->class_dev);
619 }
620 
621 EXPORT_SYMBOL(mmc_free_host);
622