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 "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
35 static DEFINE_IDA(mmc_host_ida);
36
37 #ifdef CONFIG_PM_SLEEP
mmc_host_class_prepare(struct device * dev)38 static 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
mmc_host_class_complete(struct device * dev)56 static 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
63 static 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
mmc_host_classdev_release(struct device * dev)73 static 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_simple_remove(&mmc_host_ida, host->index);
79 kfree(host);
80 }
81
mmc_host_classdev_shutdown(struct device * dev)82 static 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
90 static 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
mmc_register_host_class(void)97 int mmc_register_host_class(void)
98 {
99 return class_register(&mmc_host_class);
100 }
101
mmc_unregister_host_class(void)102 void mmc_unregister_host_class(void)
103 {
104 class_unregister(&mmc_host_class);
105 }
106
mmc_retune_enable(struct mmc_host * host)107 void mmc_retune_enable(struct mmc_host *host)
108 {
109 host->can_retune = 1;
110 if (host->retune_period)
111 mod_timer(&host->retune_timer,
112 jiffies + host->retune_period * HZ);
113 }
114
115 /*
116 * Pause re-tuning for a small set of operations. The pause begins after the
117 * next command and after first doing re-tuning.
118 */
mmc_retune_pause(struct mmc_host * host)119 void mmc_retune_pause(struct mmc_host *host)
120 {
121 if (!host->retune_paused) {
122 host->retune_paused = 1;
123 mmc_retune_needed(host);
124 mmc_retune_hold(host);
125 }
126 }
127 EXPORT_SYMBOL(mmc_retune_pause);
128
mmc_retune_unpause(struct mmc_host * host)129 void mmc_retune_unpause(struct mmc_host *host)
130 {
131 if (host->retune_paused) {
132 host->retune_paused = 0;
133 mmc_retune_release(host);
134 }
135 }
136 EXPORT_SYMBOL(mmc_retune_unpause);
137
mmc_retune_disable(struct mmc_host * host)138 void mmc_retune_disable(struct mmc_host *host)
139 {
140 mmc_retune_unpause(host);
141 host->can_retune = 0;
142 del_timer_sync(&host->retune_timer);
143 host->retune_now = 0;
144 host->need_retune = 0;
145 }
146
mmc_retune_timer_stop(struct mmc_host * host)147 void mmc_retune_timer_stop(struct mmc_host *host)
148 {
149 del_timer_sync(&host->retune_timer);
150 }
151 EXPORT_SYMBOL(mmc_retune_timer_stop);
152
mmc_retune_hold(struct mmc_host * host)153 void mmc_retune_hold(struct mmc_host *host)
154 {
155 if (!host->hold_retune)
156 host->retune_now = 1;
157 host->hold_retune += 1;
158 }
159
mmc_retune_release(struct mmc_host * host)160 void mmc_retune_release(struct mmc_host *host)
161 {
162 if (host->hold_retune)
163 host->hold_retune -= 1;
164 else
165 WARN_ON(1);
166 }
167 EXPORT_SYMBOL(mmc_retune_release);
168
mmc_retune(struct mmc_host * host)169 int mmc_retune(struct mmc_host *host)
170 {
171 bool return_to_hs400 = false;
172 int err;
173
174 if (host->retune_now)
175 host->retune_now = 0;
176 else
177 return 0;
178
179 if (!host->need_retune || host->doing_retune || !host->card)
180 return 0;
181
182 host->need_retune = 0;
183
184 host->doing_retune = 1;
185
186 if (host->ios.timing == MMC_TIMING_MMC_HS400) {
187 err = mmc_hs400_to_hs200(host->card);
188 if (err)
189 goto out;
190
191 return_to_hs400 = true;
192 }
193
194 err = mmc_execute_tuning(host->card);
195 if (err)
196 goto out;
197
198 if (return_to_hs400)
199 err = mmc_hs200_to_hs400(host->card);
200 out:
201 host->doing_retune = 0;
202
203 return err;
204 }
205
mmc_retune_timer(struct timer_list * t)206 static void mmc_retune_timer(struct timer_list *t)
207 {
208 struct mmc_host *host = from_timer(host, t, retune_timer);
209
210 mmc_retune_needed(host);
211 }
212
213 /**
214 * mmc_of_parse() - parse host's device-tree node
215 * @host: host whose node should be parsed.
216 *
217 * To keep the rest of the MMC subsystem unaware of whether DT has been
218 * used to to instantiate and configure this host instance or not, we
219 * parse the properties and set respective generic mmc-host flags and
220 * parameters.
221 */
mmc_of_parse(struct mmc_host * host)222 int mmc_of_parse(struct mmc_host *host)
223 {
224 struct device *dev = host->parent;
225 u32 bus_width, drv_type, cd_debounce_delay_ms;
226 int ret;
227
228 if (!dev || !dev_fwnode(dev))
229 return 0;
230
231 /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
232 if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) {
233 dev_dbg(host->parent,
234 "\"bus-width\" property is missing, assuming 1 bit.\n");
235 bus_width = 1;
236 }
237
238 switch (bus_width) {
239 case 8:
240 host->caps |= MMC_CAP_8_BIT_DATA;
241 fallthrough; /* Hosts capable of 8-bit can also do 4 bits */
242 case 4:
243 host->caps |= MMC_CAP_4_BIT_DATA;
244 break;
245 case 1:
246 break;
247 default:
248 dev_err(host->parent,
249 "Invalid \"bus-width\" value %u!\n", bus_width);
250 return -EINVAL;
251 }
252
253 /* f_max is obtained from the optional "max-frequency" property */
254 device_property_read_u32(dev, "max-frequency", &host->f_max);
255
256 /*
257 * Configure CD and WP pins. They are both by default active low to
258 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
259 * mmc-gpio helpers are used to attach, configure and use them. If
260 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
261 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
262 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
263 * is set. If the "non-removable" property is found, the
264 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
265 * configuration is performed.
266 */
267
268 /* Parse Card Detection */
269
270 if (device_property_read_bool(dev, "non-removable")) {
271 host->caps |= MMC_CAP_NONREMOVABLE;
272 } else {
273 if (device_property_read_bool(dev, "cd-inverted"))
274 host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
275
276 if (device_property_read_u32(dev, "cd-debounce-delay-ms",
277 &cd_debounce_delay_ms))
278 cd_debounce_delay_ms = 200;
279
280 if (device_property_read_bool(dev, "broken-cd"))
281 host->caps |= MMC_CAP_NEEDS_POLL;
282
283 ret = mmc_gpiod_request_cd(host, "cd", 0, false,
284 cd_debounce_delay_ms * 1000);
285 if (!ret)
286 dev_info(host->parent, "Got CD GPIO\n");
287 else if (ret != -ENOENT && ret != -ENOSYS)
288 return ret;
289 }
290
291 /* Parse Write Protection */
292
293 if (device_property_read_bool(dev, "wp-inverted"))
294 host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
295
296 ret = mmc_gpiod_request_ro(host, "wp", 0, 0);
297 if (!ret)
298 dev_info(host->parent, "Got WP GPIO\n");
299 else if (ret != -ENOENT && ret != -ENOSYS)
300 return ret;
301
302 if (device_property_read_bool(dev, "disable-wp"))
303 host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
304
305 if (device_property_read_bool(dev, "cap-sd-highspeed"))
306 host->caps |= MMC_CAP_SD_HIGHSPEED;
307 if (device_property_read_bool(dev, "cap-mmc-highspeed"))
308 host->caps |= MMC_CAP_MMC_HIGHSPEED;
309 if (device_property_read_bool(dev, "sd-uhs-sdr12"))
310 host->caps |= MMC_CAP_UHS_SDR12;
311 if (device_property_read_bool(dev, "sd-uhs-sdr25"))
312 host->caps |= MMC_CAP_UHS_SDR25;
313 if (device_property_read_bool(dev, "sd-uhs-sdr50"))
314 host->caps |= MMC_CAP_UHS_SDR50;
315 if (device_property_read_bool(dev, "sd-uhs-sdr104"))
316 host->caps |= MMC_CAP_UHS_SDR104;
317 if (device_property_read_bool(dev, "sd-uhs-ddr50"))
318 host->caps |= MMC_CAP_UHS_DDR50;
319 if (device_property_read_bool(dev, "cap-power-off-card"))
320 host->caps |= MMC_CAP_POWER_OFF_CARD;
321 if (device_property_read_bool(dev, "cap-mmc-hw-reset"))
322 host->caps |= MMC_CAP_HW_RESET;
323 if (device_property_read_bool(dev, "cap-sdio-irq"))
324 host->caps |= MMC_CAP_SDIO_IRQ;
325 if (device_property_read_bool(dev, "full-pwr-cycle"))
326 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
327 if (device_property_read_bool(dev, "full-pwr-cycle-in-suspend"))
328 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND;
329 if (device_property_read_bool(dev, "keep-power-in-suspend"))
330 host->pm_caps |= MMC_PM_KEEP_POWER;
331 if (device_property_read_bool(dev, "wakeup-source") ||
332 device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
333 host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
334 if (device_property_read_bool(dev, "mmc-ddr-3_3v"))
335 host->caps |= MMC_CAP_3_3V_DDR;
336 if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
337 host->caps |= MMC_CAP_1_8V_DDR;
338 if (device_property_read_bool(dev, "mmc-ddr-1_2v"))
339 host->caps |= MMC_CAP_1_2V_DDR;
340 if (device_property_read_bool(dev, "mmc-hs200-1_8v"))
341 host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
342 if (device_property_read_bool(dev, "mmc-hs200-1_2v"))
343 host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
344 if (device_property_read_bool(dev, "mmc-hs400-1_8v"))
345 host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
346 if (device_property_read_bool(dev, "mmc-hs400-1_2v"))
347 host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
348 if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe"))
349 host->caps2 |= MMC_CAP2_HS400_ES;
350 if (device_property_read_bool(dev, "no-sdio"))
351 host->caps2 |= MMC_CAP2_NO_SDIO;
352 if (device_property_read_bool(dev, "no-sd"))
353 host->caps2 |= MMC_CAP2_NO_SD;
354 if (device_property_read_bool(dev, "no-mmc"))
355 host->caps2 |= MMC_CAP2_NO_MMC;
356
357 /* Must be after "non-removable" check */
358 if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) {
359 if (host->caps & MMC_CAP_NONREMOVABLE)
360 host->fixed_drv_type = drv_type;
361 else
362 dev_err(host->parent,
363 "can't use fixed driver type, media is removable\n");
364 }
365
366 host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr);
367 if (host->dsr_req && (host->dsr & ~0xffff)) {
368 dev_err(host->parent,
369 "device tree specified broken value for DSR: 0x%x, ignoring\n",
370 host->dsr);
371 host->dsr_req = 0;
372 }
373
374 device_property_read_u32(dev, "post-power-on-delay-ms",
375 &host->ios.power_delay_ms);
376
377 return mmc_pwrseq_alloc(host);
378 }
379
380 EXPORT_SYMBOL(mmc_of_parse);
381
382 /**
383 * mmc_of_parse_voltage - return mask of supported voltages
384 * @np: The device node need to be parsed.
385 * @mask: mask of voltages available for MMC/SD/SDIO
386 *
387 * Parse the "voltage-ranges" DT property, returning zero if it is not
388 * found, negative errno if the voltage-range specification is invalid,
389 * or one if the voltage-range is specified and successfully parsed.
390 */
mmc_of_parse_voltage(struct device_node * np,u32 * mask)391 int mmc_of_parse_voltage(struct device_node *np, u32 *mask)
392 {
393 const u32 *voltage_ranges;
394 int num_ranges, i;
395
396 voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
397 if (!voltage_ranges) {
398 pr_debug("%pOF: voltage-ranges unspecified\n", np);
399 return 0;
400 }
401 num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
402 if (!num_ranges) {
403 pr_err("%pOF: voltage-ranges empty\n", np);
404 return -EINVAL;
405 }
406
407 for (i = 0; i < num_ranges; i++) {
408 const int j = i * 2;
409 u32 ocr_mask;
410
411 ocr_mask = mmc_vddrange_to_ocrmask(
412 be32_to_cpu(voltage_ranges[j]),
413 be32_to_cpu(voltage_ranges[j + 1]));
414 if (!ocr_mask) {
415 pr_err("%pOF: voltage-range #%d is invalid\n",
416 np, i);
417 return -EINVAL;
418 }
419 *mask |= ocr_mask;
420 }
421
422 return 1;
423 }
424 EXPORT_SYMBOL(mmc_of_parse_voltage);
425
426 /**
427 * mmc_first_nonreserved_index() - get the first index that is not reserved
428 */
mmc_first_nonreserved_index(void)429 static int mmc_first_nonreserved_index(void)
430 {
431 int max;
432
433 max = of_alias_get_highest_id("mmc");
434 if (max < 0)
435 return 0;
436
437 return max + 1;
438 }
439
440 /**
441 * mmc_alloc_host - initialise the per-host structure.
442 * @extra: sizeof private data structure
443 * @dev: pointer to host device model structure
444 *
445 * Initialise the per-host structure.
446 */
mmc_alloc_host(int extra,struct device * dev)447 struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
448 {
449 int index;
450 struct mmc_host *host;
451 int alias_id, min_idx, max_idx;
452
453 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
454 if (!host)
455 return NULL;
456
457 /* scanning will be enabled when we're ready */
458 host->rescan_disable = 1;
459
460 alias_id = of_alias_get_id(dev->of_node, "mmc");
461 if (alias_id >= 0) {
462 index = alias_id;
463 } else {
464 min_idx = mmc_first_nonreserved_index();
465 max_idx = 0;
466
467 index = ida_simple_get(&mmc_host_ida, min_idx, max_idx, GFP_KERNEL);
468 if (index < 0) {
469 kfree(host);
470 return NULL;
471 }
472 }
473
474 host->index = index;
475
476 dev_set_name(&host->class_dev, "mmc%d", host->index);
477 host->ws = wakeup_source_register(NULL, dev_name(&host->class_dev));
478
479 host->parent = dev;
480 host->class_dev.parent = dev;
481 host->class_dev.class = &mmc_host_class;
482 device_initialize(&host->class_dev);
483 device_enable_async_suspend(&host->class_dev);
484
485 if (mmc_gpio_alloc(host)) {
486 put_device(&host->class_dev);
487 return NULL;
488 }
489
490 spin_lock_init(&host->lock);
491 init_waitqueue_head(&host->wq);
492 INIT_DELAYED_WORK(&host->detect, mmc_rescan);
493 INIT_DELAYED_WORK(&host->sdio_irq_work, sdio_irq_work);
494 timer_setup(&host->retune_timer, mmc_retune_timer, 0);
495
496 /*
497 * By default, hosts do not support SGIO or large requests.
498 * They have to set these according to their abilities.
499 */
500 host->max_segs = 1;
501 host->max_seg_size = PAGE_SIZE;
502
503 host->max_req_size = PAGE_SIZE;
504 host->max_blk_size = 512;
505 host->max_blk_count = PAGE_SIZE / 512;
506
507 host->fixed_drv_type = -EINVAL;
508 host->ios.power_delay_ms = 10;
509 host->ios.power_mode = MMC_POWER_UNDEFINED;
510
511 return host;
512 }
513
514 EXPORT_SYMBOL(mmc_alloc_host);
515
mmc_validate_host_caps(struct mmc_host * host)516 static int mmc_validate_host_caps(struct mmc_host *host)
517 {
518 if (host->caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) {
519 dev_warn(host->parent, "missing ->enable_sdio_irq() ops\n");
520 return -EINVAL;
521 }
522
523 return 0;
524 }
525
526 /**
527 * mmc_add_host - initialise host hardware
528 * @host: mmc host
529 *
530 * Register the host with the driver model. The host must be
531 * prepared to start servicing requests before this function
532 * completes.
533 */
mmc_add_host(struct mmc_host * host)534 int mmc_add_host(struct mmc_host *host)
535 {
536 int err;
537
538 err = mmc_validate_host_caps(host);
539 if (err)
540 return err;
541
542 err = device_add(&host->class_dev);
543 if (err)
544 return err;
545
546 led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
547
548 #ifdef CONFIG_DEBUG_FS
549 mmc_add_host_debugfs(host);
550 #endif
551
552 mmc_start_host(host);
553 return 0;
554 }
555
556 EXPORT_SYMBOL(mmc_add_host);
557
558 /**
559 * mmc_remove_host - remove host hardware
560 * @host: mmc host
561 *
562 * Unregister and remove all cards associated with this host,
563 * and power down the MMC bus. No new requests will be issued
564 * after this function has returned.
565 */
mmc_remove_host(struct mmc_host * host)566 void mmc_remove_host(struct mmc_host *host)
567 {
568 mmc_stop_host(host);
569
570 #ifdef CONFIG_DEBUG_FS
571 mmc_remove_host_debugfs(host);
572 #endif
573
574 device_del(&host->class_dev);
575
576 led_trigger_unregister_simple(host->led);
577 }
578
579 EXPORT_SYMBOL(mmc_remove_host);
580
581 /**
582 * mmc_free_host - free the host structure
583 * @host: mmc host
584 *
585 * Free the host once all references to it have been dropped.
586 */
mmc_free_host(struct mmc_host * host)587 void mmc_free_host(struct mmc_host *host)
588 {
589 mmc_pwrseq_free(host);
590 put_device(&host->class_dev);
591 }
592
593 EXPORT_SYMBOL(mmc_free_host);
594