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1/*
2 * linux/drivers/mmc/core/host.c
3 *
4 * Copyright (C) 2003 Russell King, All Rights Reserved.
5 * Copyright (C) 2007-2008 Pierre Ossman
6 * Copyright (C) 2010 Linus Walleij
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 * MMC host class device management
13 */
14
15#include <linux/device.h>
16#include <linux/err.h>
17#include <linux/idr.h>
18#include <linux/of.h>
19#include <linux/of_gpio.h>
20#include <linux/pagemap.h>
21#include <linux/export.h>
22#include <linux/leds.h>
23#include <linux/slab.h>
24#include <linux/suspend.h>
25
26#include <linux/mmc/host.h>
27#include <linux/mmc/card.h>
28#include <linux/mmc/slot-gpio.h>
29
30#include "core.h"
31#include "host.h"
32
33#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
34
35static void mmc_host_classdev_release(struct device *dev)
36{
37 struct mmc_host *host = cls_dev_to_mmc_host(dev);
38 mutex_destroy(&host->slot.lock);
39 kfree(host);
40}
41
42static struct class mmc_host_class = {
43 .name = "mmc_host",
44 .dev_release = mmc_host_classdev_release,
45};
46
47int mmc_register_host_class(void)
48{
49 return class_register(&mmc_host_class);
50}
51
52void mmc_unregister_host_class(void)
53{
54 class_unregister(&mmc_host_class);
55}
56
57static DEFINE_IDR(mmc_host_idr);
58static DEFINE_SPINLOCK(mmc_host_lock);
59
60#ifdef CONFIG_MMC_CLKGATE
61static ssize_t clkgate_delay_show(struct device *dev,
62 struct device_attribute *attr, char *buf)
63{
64 struct mmc_host *host = cls_dev_to_mmc_host(dev);
65 return snprintf(buf, PAGE_SIZE, "%lu\n", host->clkgate_delay);
66}
67
68static ssize_t clkgate_delay_store(struct device *dev,
69 struct device_attribute *attr, const char *buf, size_t count)
70{
71 struct mmc_host *host = cls_dev_to_mmc_host(dev);
72 unsigned long flags, value;
73
74 if (kstrtoul(buf, 0, &value))
75 return -EINVAL;
76
77 spin_lock_irqsave(&host->clk_lock, flags);
78 host->clkgate_delay = value;
79 spin_unlock_irqrestore(&host->clk_lock, flags);
80 return count;
81}
82
83/*
84 * Enabling clock gating will make the core call out to the host
85 * once up and once down when it performs a request or card operation
86 * intermingled in any fashion. The driver will see this through
87 * set_ios() operations with ios.clock field set to 0 to gate (disable)
88 * the block clock, and to the old frequency to enable it again.
89 */
90static void mmc_host_clk_gate_delayed(struct mmc_host *host)
91{
92 unsigned long tick_ns;
93 unsigned long freq = host->ios.clock;
94 unsigned long flags;
95
96 if (!freq) {
97 pr_debug("%s: frequency set to 0 in disable function, "
98 "this means the clock is already disabled.\n",
99 mmc_hostname(host));
100 return;
101 }
102 /*
103 * New requests may have appeared while we were scheduling,
104 * then there is no reason to delay the check before
105 * clk_disable().
106 */
107 spin_lock_irqsave(&host->clk_lock, flags);
108
109 /*
110 * Delay n bus cycles (at least 8 from MMC spec) before attempting
111 * to disable the MCI block clock. The reference count may have
112 * gone up again after this delay due to rescheduling!
113 */
114 if (!host->clk_requests) {
115 spin_unlock_irqrestore(&host->clk_lock, flags);
116 tick_ns = DIV_ROUND_UP(1000000000, freq);
117 ndelay(host->clk_delay * tick_ns);
118 } else {
119 /* New users appeared while waiting for this work */
120 spin_unlock_irqrestore(&host->clk_lock, flags);
121 return;
122 }
123 mutex_lock(&host->clk_gate_mutex);
124 spin_lock_irqsave(&host->clk_lock, flags);
125 if (!host->clk_requests) {
126 spin_unlock_irqrestore(&host->clk_lock, flags);
127 /* This will set host->ios.clock to 0 */
128 mmc_gate_clock(host);
129 spin_lock_irqsave(&host->clk_lock, flags);
130 pr_debug("%s: gated MCI clock\n", mmc_hostname(host));
131 }
132 spin_unlock_irqrestore(&host->clk_lock, flags);
133 mutex_unlock(&host->clk_gate_mutex);
134}
135
136/*
137 * Internal work. Work to disable the clock at some later point.
138 */
139static void mmc_host_clk_gate_work(struct work_struct *work)
140{
141 struct mmc_host *host = container_of(work, struct mmc_host,
142 clk_gate_work.work);
143
144 mmc_host_clk_gate_delayed(host);
145}
146
147/**
148 * mmc_host_clk_hold - ungate hardware MCI clocks
149 * @host: host to ungate.
150 *
151 * Makes sure the host ios.clock is restored to a non-zero value
152 * past this call. Increase clock reference count and ungate clock
153 * if we're the first user.
154 */
155void mmc_host_clk_hold(struct mmc_host *host)
156{
157 unsigned long flags;
158
159 /* cancel any clock gating work scheduled by mmc_host_clk_release() */
160 cancel_delayed_work_sync(&host->clk_gate_work);
161 mutex_lock(&host->clk_gate_mutex);
162 spin_lock_irqsave(&host->clk_lock, flags);
163 if (host->clk_gated) {
164 spin_unlock_irqrestore(&host->clk_lock, flags);
165 mmc_ungate_clock(host);
166 spin_lock_irqsave(&host->clk_lock, flags);
167 pr_debug("%s: ungated MCI clock\n", mmc_hostname(host));
168 }
169 host->clk_requests++;
170 spin_unlock_irqrestore(&host->clk_lock, flags);
171 mutex_unlock(&host->clk_gate_mutex);
172}
173
174/**
175 * mmc_host_may_gate_card - check if this card may be gated
176 * @card: card to check.
177 */
178static bool mmc_host_may_gate_card(struct mmc_card *card)
179{
180 /* If there is no card we may gate it */
181 if (!card)
182 return true;
183 /*
184 * Don't gate SDIO cards! These need to be clocked at all times
185 * since they may be independent systems generating interrupts
186 * and other events. The clock requests counter from the core will
187 * go down to zero since the core does not need it, but we will not
188 * gate the clock, because there is somebody out there that may still
189 * be using it.
190 */
191 return !(card->quirks & MMC_QUIRK_BROKEN_CLK_GATING);
192}
193
194/**
195 * mmc_host_clk_release - gate off hardware MCI clocks
196 * @host: host to gate.
197 *
198 * Calls the host driver with ios.clock set to zero as often as possible
199 * in order to gate off hardware MCI clocks. Decrease clock reference
200 * count and schedule disabling of clock.
201 */
202void mmc_host_clk_release(struct mmc_host *host)
203{
204 unsigned long flags;
205
206 spin_lock_irqsave(&host->clk_lock, flags);
207 host->clk_requests--;
208 if (mmc_host_may_gate_card(host->card) &&
209 !host->clk_requests)
210 schedule_delayed_work(&host->clk_gate_work,
211 msecs_to_jiffies(host->clkgate_delay));
212 spin_unlock_irqrestore(&host->clk_lock, flags);
213}
214
215/**
216 * mmc_host_clk_rate - get current clock frequency setting
217 * @host: host to get the clock frequency for.
218 *
219 * Returns current clock frequency regardless of gating.
220 */
221unsigned int mmc_host_clk_rate(struct mmc_host *host)
222{
223 unsigned long freq;
224 unsigned long flags;
225
226 spin_lock_irqsave(&host->clk_lock, flags);
227 if (host->clk_gated)
228 freq = host->clk_old;
229 else
230 freq = host->ios.clock;
231 spin_unlock_irqrestore(&host->clk_lock, flags);
232 return freq;
233}
234
235/**
236 * mmc_host_clk_init - set up clock gating code
237 * @host: host with potential clock to control
238 */
239static inline void mmc_host_clk_init(struct mmc_host *host)
240{
241 host->clk_requests = 0;
242 /* Hold MCI clock for 8 cycles by default */
243 host->clk_delay = 8;
244 /*
245 * Default clock gating delay is 0ms to avoid wasting power.
246 * This value can be tuned by writing into sysfs entry.
247 */
248 host->clkgate_delay = 0;
249 host->clk_gated = false;
250 INIT_DELAYED_WORK(&host->clk_gate_work, mmc_host_clk_gate_work);
251 spin_lock_init(&host->clk_lock);
252 mutex_init(&host->clk_gate_mutex);
253}
254
255/**
256 * mmc_host_clk_exit - shut down clock gating code
257 * @host: host with potential clock to control
258 */
259static inline void mmc_host_clk_exit(struct mmc_host *host)
260{
261 /*
262 * Wait for any outstanding gate and then make sure we're
263 * ungated before exiting.
264 */
265 if (cancel_delayed_work_sync(&host->clk_gate_work))
266 mmc_host_clk_gate_delayed(host);
267 if (host->clk_gated)
268 mmc_host_clk_hold(host);
269 /* There should be only one user now */
270 WARN_ON(host->clk_requests > 1);
271}
272
273static inline void mmc_host_clk_sysfs_init(struct mmc_host *host)
274{
275 host->clkgate_delay_attr.show = clkgate_delay_show;
276 host->clkgate_delay_attr.store = clkgate_delay_store;
277 sysfs_attr_init(&host->clkgate_delay_attr.attr);
278 host->clkgate_delay_attr.attr.name = "clkgate_delay";
279 host->clkgate_delay_attr.attr.mode = S_IRUGO | S_IWUSR;
280 if (device_create_file(&host->class_dev, &host->clkgate_delay_attr))
281 pr_err("%s: Failed to create clkgate_delay sysfs entry\n",
282 mmc_hostname(host));
283}
284#else
285
286static inline void mmc_host_clk_init(struct mmc_host *host)
287{
288}
289
290static inline void mmc_host_clk_exit(struct mmc_host *host)
291{
292}
293
294static inline void mmc_host_clk_sysfs_init(struct mmc_host *host)
295{
296}
297
298#endif
299
300/**
301 * mmc_of_parse() - parse host's device-tree node
302 * @host: host whose node should be parsed.
303 *
304 * To keep the rest of the MMC subsystem unaware of whether DT has been
305 * used to to instantiate and configure this host instance or not, we
306 * parse the properties and set respective generic mmc-host flags and
307 * parameters.
308 */
309int mmc_of_parse(struct mmc_host *host)
310{
311 struct device_node *np;
312 u32 bus_width;
313 bool explicit_inv_wp, gpio_inv_wp = false;
314 enum of_gpio_flags flags;
315 int len, ret, gpio;
316
317 if (!host->parent || !host->parent->of_node)
318 return 0;
319
320 np = host->parent->of_node;
321
322 /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
323 if (of_property_read_u32(np, "bus-width", &bus_width) < 0) {
324 dev_dbg(host->parent,
325 "\"bus-width\" property is missing, assuming 1 bit.\n");
326 bus_width = 1;
327 }
328
329 switch (bus_width) {
330 case 8:
331 host->caps |= MMC_CAP_8_BIT_DATA;
332 /* Hosts capable of 8-bit transfers can also do 4 bits */
333 case 4:
334 host->caps |= MMC_CAP_4_BIT_DATA;
335 break;
336 case 1:
337 break;
338 default:
339 dev_err(host->parent,
340 "Invalid \"bus-width\" value %u!\n", bus_width);
341 return -EINVAL;
342 }
343
344 /* f_max is obtained from the optional "max-frequency" property */
345 of_property_read_u32(np, "max-frequency", &host->f_max);
346
347 /*
348 * Configure CD and WP pins. They are both by default active low to
349 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
350 * mmc-gpio helpers are used to attach, configure and use them. If
351 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
352 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
353 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
354 * is set. If the "non-removable" property is found, the
355 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
356 * configuration is performed.
357 */
358
359 /* Parse Card Detection */
360 if (of_find_property(np, "non-removable", &len)) {
361 host->caps |= MMC_CAP_NONREMOVABLE;
362 } else {
363 bool explicit_inv_cd, gpio_inv_cd = false;
364
365 explicit_inv_cd = of_property_read_bool(np, "cd-inverted");
366
367 if (of_find_property(np, "broken-cd", &len))
368 host->caps |= MMC_CAP_NEEDS_POLL;
369
370 gpio = of_get_named_gpio_flags(np, "cd-gpios", 0, &flags);
371 if (gpio == -EPROBE_DEFER)
372 return gpio;
373 if (gpio_is_valid(gpio)) {
374 if (!(flags & OF_GPIO_ACTIVE_LOW))
375 gpio_inv_cd = true;
376
377 ret = mmc_gpio_request_cd(host, gpio, 0);
378 if (ret < 0) {
379 dev_err(host->parent,
380 "Failed to request CD GPIO #%d: %d!\n",
381 gpio, ret);
382 return ret;
383 } else {
384 dev_info(host->parent, "Got CD GPIO #%d.\n",
385 gpio);
386 }
387 }
388
389 if (explicit_inv_cd ^ gpio_inv_cd)
390 host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
391 }
392
393 /* Parse Write Protection */
394 explicit_inv_wp = of_property_read_bool(np, "wp-inverted");
395
396 gpio = of_get_named_gpio_flags(np, "wp-gpios", 0, &flags);
397 if (gpio == -EPROBE_DEFER) {
398 ret = -EPROBE_DEFER;
399 goto out;
400 }
401 if (gpio_is_valid(gpio)) {
402 if (!(flags & OF_GPIO_ACTIVE_LOW))
403 gpio_inv_wp = true;
404
405 ret = mmc_gpio_request_ro(host, gpio);
406 if (ret < 0) {
407 dev_err(host->parent,
408 "Failed to request WP GPIO: %d!\n", ret);
409 goto out;
410 } else {
411 dev_info(host->parent, "Got WP GPIO #%d.\n",
412 gpio);
413 }
414 }
415 if (explicit_inv_wp ^ gpio_inv_wp)
416 host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
417
418 if (of_find_property(np, "cap-sd-highspeed", &len))
419 host->caps |= MMC_CAP_SD_HIGHSPEED;
420 if (of_find_property(np, "cap-mmc-highspeed", &len))
421 host->caps |= MMC_CAP_MMC_HIGHSPEED;
422 if (of_find_property(np, "sd-uhs-sdr12", &len))
423 host->caps |= MMC_CAP_UHS_SDR12;
424 if (of_find_property(np, "sd-uhs-sdr25", &len))
425 host->caps |= MMC_CAP_UHS_SDR25;
426 if (of_find_property(np, "sd-uhs-sdr50", &len))
427 host->caps |= MMC_CAP_UHS_SDR50;
428 if (of_find_property(np, "sd-uhs-sdr104", &len))
429 host->caps |= MMC_CAP_UHS_SDR104;
430 if (of_find_property(np, "sd-uhs-ddr50", &len))
431 host->caps |= MMC_CAP_UHS_DDR50;
432 if (of_find_property(np, "cap-power-off-card", &len))
433 host->caps |= MMC_CAP_POWER_OFF_CARD;
434 if (of_find_property(np, "cap-sdio-irq", &len))
435 host->caps |= MMC_CAP_SDIO_IRQ;
436 if (of_find_property(np, "full-pwr-cycle", &len))
437 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
438 if (of_find_property(np, "keep-power-in-suspend", &len))
439 host->pm_caps |= MMC_PM_KEEP_POWER;
440 if (of_find_property(np, "enable-sdio-wakeup", &len))
441 host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
442 if (of_find_property(np, "mmc-ddr-1_8v", &len))
443 host->caps |= MMC_CAP_1_8V_DDR;
444 if (of_find_property(np, "mmc-ddr-1_2v", &len))
445 host->caps |= MMC_CAP_1_2V_DDR;
446 if (of_find_property(np, "mmc-hs200-1_8v", &len))
447 host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
448 if (of_find_property(np, "mmc-hs200-1_2v", &len))
449 host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
450
451 return 0;
452
453out:
454 mmc_gpio_free_cd(host);
455 return ret;
456}
457
458EXPORT_SYMBOL(mmc_of_parse);
459
460/**
461 * mmc_alloc_host - initialise the per-host structure.
462 * @extra: sizeof private data structure
463 * @dev: pointer to host device model structure
464 *
465 * Initialise the per-host structure.
466 */
467struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
468{
469 int err;
470 struct mmc_host *host;
471
472 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
473 if (!host)
474 return NULL;
475
476 /* scanning will be enabled when we're ready */
477 host->rescan_disable = 1;
478 idr_preload(GFP_KERNEL);
479 spin_lock(&mmc_host_lock);
480 err = idr_alloc(&mmc_host_idr, host, 0, 0, GFP_NOWAIT);
481 if (err >= 0)
482 host->index = err;
483 spin_unlock(&mmc_host_lock);
484 idr_preload_end();
485 if (err < 0)
486 goto free;
487
488 dev_set_name(&host->class_dev, "mmc%d", host->index);
489
490 host->parent = dev;
491 host->class_dev.parent = dev;
492 host->class_dev.class = &mmc_host_class;
493 device_initialize(&host->class_dev);
494
495 mmc_host_clk_init(host);
496
497 mutex_init(&host->slot.lock);
498 host->slot.cd_irq = -EINVAL;
499
500 spin_lock_init(&host->lock);
501 init_waitqueue_head(&host->wq);
502 INIT_DELAYED_WORK(&host->detect, mmc_rescan);
503#ifdef CONFIG_PM
504 host->pm_notify.notifier_call = mmc_pm_notify;
505#endif
506
507 /*
508 * By default, hosts do not support SGIO or large requests.
509 * They have to set these according to their abilities.
510 */
511 host->max_segs = 1;
512 host->max_seg_size = PAGE_CACHE_SIZE;
513
514 host->max_req_size = PAGE_CACHE_SIZE;
515 host->max_blk_size = 512;
516 host->max_blk_count = PAGE_CACHE_SIZE / 512;
517
518 return host;
519
520free:
521 kfree(host);
522 return NULL;
523}
524
525EXPORT_SYMBOL(mmc_alloc_host);
526
527/**
528 * mmc_add_host - initialise host hardware
529 * @host: mmc host
530 *
531 * Register the host with the driver model. The host must be
532 * prepared to start servicing requests before this function
533 * completes.
534 */
535int mmc_add_host(struct mmc_host *host)
536{
537 int err;
538
539 WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) &&
540 !host->ops->enable_sdio_irq);
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 mmc_host_clk_sysfs_init(host);
552
553 mmc_start_host(host);
554 register_pm_notifier(&host->pm_notify);
555
556 return 0;
557}
558
559EXPORT_SYMBOL(mmc_add_host);
560
561/**
562 * mmc_remove_host - remove host hardware
563 * @host: mmc host
564 *
565 * Unregister and remove all cards associated with this host,
566 * and power down the MMC bus. No new requests will be issued
567 * after this function has returned.
568 */
569void mmc_remove_host(struct mmc_host *host)
570{
571 unregister_pm_notifier(&host->pm_notify);
572 mmc_stop_host(host);
573
574#ifdef CONFIG_DEBUG_FS
575 mmc_remove_host_debugfs(host);
576#endif
577
578 device_del(&host->class_dev);
579
580 led_trigger_unregister_simple(host->led);
581
582 mmc_host_clk_exit(host);
583}
584
585EXPORT_SYMBOL(mmc_remove_host);
586
587/**
588 * mmc_free_host - free the host structure
589 * @host: mmc host
590 *
591 * Free the host once all references to it have been dropped.
592 */
593void mmc_free_host(struct mmc_host *host)
594{
595 spin_lock(&mmc_host_lock);
596 idr_remove(&mmc_host_idr, host->index);
597 spin_unlock(&mmc_host_lock);
598
599 put_device(&host->class_dev);
600}
601
602EXPORT_SYMBOL(mmc_free_host);
1/*
2 * linux/drivers/mmc/core/host.c
3 *
4 * Copyright (C) 2003 Russell King, All Rights Reserved.
5 * Copyright (C) 2007-2008 Pierre Ossman
6 * Copyright (C) 2010 Linus Walleij
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 * MMC host class device management
13 */
14
15#include <linux/device.h>
16#include <linux/err.h>
17#include <linux/idr.h>
18#include <linux/of.h>
19#include <linux/of_gpio.h>
20#include <linux/pagemap.h>
21#include <linux/export.h>
22#include <linux/leds.h>
23#include <linux/slab.h>
24
25#include <linux/mmc/host.h>
26#include <linux/mmc/card.h>
27#include <linux/mmc/slot-gpio.h>
28
29#include "core.h"
30#include "host.h"
31#include "slot-gpio.h"
32#include "pwrseq.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);
37static DEFINE_SPINLOCK(mmc_host_lock);
38
39static void mmc_host_classdev_release(struct device *dev)
40{
41 struct mmc_host *host = cls_dev_to_mmc_host(dev);
42 spin_lock(&mmc_host_lock);
43 ida_remove(&mmc_host_ida, host->index);
44 spin_unlock(&mmc_host_lock);
45 kfree(host);
46}
47
48static struct class mmc_host_class = {
49 .name = "mmc_host",
50 .dev_release = mmc_host_classdev_release,
51};
52
53int mmc_register_host_class(void)
54{
55 return class_register(&mmc_host_class);
56}
57
58void mmc_unregister_host_class(void)
59{
60 class_unregister(&mmc_host_class);
61}
62
63void mmc_retune_enable(struct mmc_host *host)
64{
65 host->can_retune = 1;
66 if (host->retune_period)
67 mod_timer(&host->retune_timer,
68 jiffies + host->retune_period * HZ);
69}
70
71/*
72 * Pause re-tuning for a small set of operations. The pause begins after the
73 * next command and after first doing re-tuning.
74 */
75void mmc_retune_pause(struct mmc_host *host)
76{
77 if (!host->retune_paused) {
78 host->retune_paused = 1;
79 mmc_retune_needed(host);
80 mmc_retune_hold(host);
81 }
82}
83EXPORT_SYMBOL(mmc_retune_pause);
84
85void mmc_retune_unpause(struct mmc_host *host)
86{
87 if (host->retune_paused) {
88 host->retune_paused = 0;
89 mmc_retune_release(host);
90 }
91}
92EXPORT_SYMBOL(mmc_retune_unpause);
93
94void mmc_retune_disable(struct mmc_host *host)
95{
96 mmc_retune_unpause(host);
97 host->can_retune = 0;
98 del_timer_sync(&host->retune_timer);
99 host->retune_now = 0;
100 host->need_retune = 0;
101}
102
103void mmc_retune_timer_stop(struct mmc_host *host)
104{
105 del_timer_sync(&host->retune_timer);
106}
107EXPORT_SYMBOL(mmc_retune_timer_stop);
108
109void mmc_retune_hold(struct mmc_host *host)
110{
111 if (!host->hold_retune)
112 host->retune_now = 1;
113 host->hold_retune += 1;
114}
115
116void mmc_retune_release(struct mmc_host *host)
117{
118 if (host->hold_retune)
119 host->hold_retune -= 1;
120 else
121 WARN_ON(1);
122}
123
124int mmc_retune(struct mmc_host *host)
125{
126 bool return_to_hs400 = false;
127 int err;
128
129 if (host->retune_now)
130 host->retune_now = 0;
131 else
132 return 0;
133
134 if (!host->need_retune || host->doing_retune || !host->card)
135 return 0;
136
137 host->need_retune = 0;
138
139 host->doing_retune = 1;
140
141 if (host->ios.timing == MMC_TIMING_MMC_HS400) {
142 err = mmc_hs400_to_hs200(host->card);
143 if (err)
144 goto out;
145
146 return_to_hs400 = true;
147
148 if (host->ops->prepare_hs400_tuning)
149 host->ops->prepare_hs400_tuning(host, &host->ios);
150 }
151
152 err = mmc_execute_tuning(host->card);
153 if (err)
154 goto out;
155
156 if (return_to_hs400)
157 err = mmc_hs200_to_hs400(host->card);
158out:
159 host->doing_retune = 0;
160
161 return err;
162}
163
164static void mmc_retune_timer(unsigned long data)
165{
166 struct mmc_host *host = (struct mmc_host *)data;
167
168 mmc_retune_needed(host);
169}
170
171/**
172 * mmc_of_parse() - parse host's device-tree node
173 * @host: host whose node should be parsed.
174 *
175 * To keep the rest of the MMC subsystem unaware of whether DT has been
176 * used to to instantiate and configure this host instance or not, we
177 * parse the properties and set respective generic mmc-host flags and
178 * parameters.
179 */
180int mmc_of_parse(struct mmc_host *host)
181{
182 struct device_node *np;
183 u32 bus_width;
184 int ret;
185 bool cd_cap_invert, cd_gpio_invert = false;
186 bool ro_cap_invert, ro_gpio_invert = false;
187
188 if (!host->parent || !host->parent->of_node)
189 return 0;
190
191 np = host->parent->of_node;
192
193 /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
194 if (of_property_read_u32(np, "bus-width", &bus_width) < 0) {
195 dev_dbg(host->parent,
196 "\"bus-width\" property is missing, assuming 1 bit.\n");
197 bus_width = 1;
198 }
199
200 switch (bus_width) {
201 case 8:
202 host->caps |= MMC_CAP_8_BIT_DATA;
203 /* Hosts capable of 8-bit transfers can also do 4 bits */
204 case 4:
205 host->caps |= MMC_CAP_4_BIT_DATA;
206 break;
207 case 1:
208 break;
209 default:
210 dev_err(host->parent,
211 "Invalid \"bus-width\" value %u!\n", bus_width);
212 return -EINVAL;
213 }
214
215 /* f_max is obtained from the optional "max-frequency" property */
216 of_property_read_u32(np, "max-frequency", &host->f_max);
217
218 /*
219 * Configure CD and WP pins. They are both by default active low to
220 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
221 * mmc-gpio helpers are used to attach, configure and use them. If
222 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
223 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
224 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
225 * is set. If the "non-removable" property is found, the
226 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
227 * configuration is performed.
228 */
229
230 /* Parse Card Detection */
231 if (of_property_read_bool(np, "non-removable")) {
232 host->caps |= MMC_CAP_NONREMOVABLE;
233 } else {
234 cd_cap_invert = of_property_read_bool(np, "cd-inverted");
235
236 if (of_property_read_bool(np, "broken-cd"))
237 host->caps |= MMC_CAP_NEEDS_POLL;
238
239 ret = mmc_gpiod_request_cd(host, "cd", 0, true,
240 0, &cd_gpio_invert);
241 if (!ret)
242 dev_info(host->parent, "Got CD GPIO\n");
243 else if (ret != -ENOENT && ret != -ENOSYS)
244 return ret;
245
246 /*
247 * There are two ways to flag that the CD line is inverted:
248 * through the cd-inverted flag and by the GPIO line itself
249 * being inverted from the GPIO subsystem. This is a leftover
250 * from the times when the GPIO subsystem did not make it
251 * possible to flag a line as inverted.
252 *
253 * If the capability on the host AND the GPIO line are
254 * both inverted, the end result is that the CD line is
255 * not inverted.
256 */
257 if (cd_cap_invert ^ cd_gpio_invert)
258 host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
259 }
260
261 /* Parse Write Protection */
262 ro_cap_invert = of_property_read_bool(np, "wp-inverted");
263
264 ret = mmc_gpiod_request_ro(host, "wp", 0, false, 0, &ro_gpio_invert);
265 if (!ret)
266 dev_info(host->parent, "Got WP GPIO\n");
267 else if (ret != -ENOENT && ret != -ENOSYS)
268 return ret;
269
270 if (of_property_read_bool(np, "disable-wp"))
271 host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
272
273 /* See the comment on CD inversion above */
274 if (ro_cap_invert ^ ro_gpio_invert)
275 host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
276
277 if (of_property_read_bool(np, "cap-sd-highspeed"))
278 host->caps |= MMC_CAP_SD_HIGHSPEED;
279 if (of_property_read_bool(np, "cap-mmc-highspeed"))
280 host->caps |= MMC_CAP_MMC_HIGHSPEED;
281 if (of_property_read_bool(np, "sd-uhs-sdr12"))
282 host->caps |= MMC_CAP_UHS_SDR12;
283 if (of_property_read_bool(np, "sd-uhs-sdr25"))
284 host->caps |= MMC_CAP_UHS_SDR25;
285 if (of_property_read_bool(np, "sd-uhs-sdr50"))
286 host->caps |= MMC_CAP_UHS_SDR50;
287 if (of_property_read_bool(np, "sd-uhs-sdr104"))
288 host->caps |= MMC_CAP_UHS_SDR104;
289 if (of_property_read_bool(np, "sd-uhs-ddr50"))
290 host->caps |= MMC_CAP_UHS_DDR50;
291 if (of_property_read_bool(np, "cap-power-off-card"))
292 host->caps |= MMC_CAP_POWER_OFF_CARD;
293 if (of_property_read_bool(np, "cap-mmc-hw-reset"))
294 host->caps |= MMC_CAP_HW_RESET;
295 if (of_property_read_bool(np, "cap-sdio-irq"))
296 host->caps |= MMC_CAP_SDIO_IRQ;
297 if (of_property_read_bool(np, "full-pwr-cycle"))
298 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
299 if (of_property_read_bool(np, "keep-power-in-suspend"))
300 host->pm_caps |= MMC_PM_KEEP_POWER;
301 if (of_property_read_bool(np, "wakeup-source") ||
302 of_property_read_bool(np, "enable-sdio-wakeup")) /* legacy */
303 host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
304 if (of_property_read_bool(np, "mmc-ddr-1_8v"))
305 host->caps |= MMC_CAP_1_8V_DDR;
306 if (of_property_read_bool(np, "mmc-ddr-1_2v"))
307 host->caps |= MMC_CAP_1_2V_DDR;
308 if (of_property_read_bool(np, "mmc-hs200-1_8v"))
309 host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
310 if (of_property_read_bool(np, "mmc-hs200-1_2v"))
311 host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
312 if (of_property_read_bool(np, "mmc-hs400-1_8v"))
313 host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
314 if (of_property_read_bool(np, "mmc-hs400-1_2v"))
315 host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
316 if (of_property_read_bool(np, "mmc-hs400-enhanced-strobe"))
317 host->caps2 |= MMC_CAP2_HS400_ES;
318 if (of_property_read_bool(np, "no-sdio"))
319 host->caps2 |= MMC_CAP2_NO_SDIO;
320 if (of_property_read_bool(np, "no-sd"))
321 host->caps2 |= MMC_CAP2_NO_SD;
322 if (of_property_read_bool(np, "no-mmc"))
323 host->caps2 |= MMC_CAP2_NO_MMC;
324
325 host->dsr_req = !of_property_read_u32(np, "dsr", &host->dsr);
326 if (host->dsr_req && (host->dsr & ~0xffff)) {
327 dev_err(host->parent,
328 "device tree specified broken value for DSR: 0x%x, ignoring\n",
329 host->dsr);
330 host->dsr_req = 0;
331 }
332
333 return mmc_pwrseq_alloc(host);
334}
335
336EXPORT_SYMBOL(mmc_of_parse);
337
338/**
339 * mmc_alloc_host - initialise the per-host structure.
340 * @extra: sizeof private data structure
341 * @dev: pointer to host device model structure
342 *
343 * Initialise the per-host structure.
344 */
345struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
346{
347 int err;
348 struct mmc_host *host;
349
350 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
351 if (!host)
352 return NULL;
353
354 /* scanning will be enabled when we're ready */
355 host->rescan_disable = 1;
356
357again:
358 if (!ida_pre_get(&mmc_host_ida, GFP_KERNEL)) {
359 kfree(host);
360 return NULL;
361 }
362
363 spin_lock(&mmc_host_lock);
364 err = ida_get_new(&mmc_host_ida, &host->index);
365 spin_unlock(&mmc_host_lock);
366
367 if (err == -EAGAIN) {
368 goto again;
369 } else if (err) {
370 kfree(host);
371 return NULL;
372 }
373
374 dev_set_name(&host->class_dev, "mmc%d", host->index);
375
376 host->parent = dev;
377 host->class_dev.parent = dev;
378 host->class_dev.class = &mmc_host_class;
379 device_initialize(&host->class_dev);
380 device_enable_async_suspend(&host->class_dev);
381
382 if (mmc_gpio_alloc(host)) {
383 put_device(&host->class_dev);
384 return NULL;
385 }
386
387 spin_lock_init(&host->lock);
388 init_waitqueue_head(&host->wq);
389 INIT_DELAYED_WORK(&host->detect, mmc_rescan);
390 setup_timer(&host->retune_timer, mmc_retune_timer, (unsigned long)host);
391
392 /*
393 * By default, hosts do not support SGIO or large requests.
394 * They have to set these according to their abilities.
395 */
396 host->max_segs = 1;
397 host->max_seg_size = PAGE_SIZE;
398
399 host->max_req_size = PAGE_SIZE;
400 host->max_blk_size = 512;
401 host->max_blk_count = PAGE_SIZE / 512;
402
403 return host;
404}
405
406EXPORT_SYMBOL(mmc_alloc_host);
407
408/**
409 * mmc_add_host - initialise host hardware
410 * @host: mmc host
411 *
412 * Register the host with the driver model. The host must be
413 * prepared to start servicing requests before this function
414 * completes.
415 */
416int mmc_add_host(struct mmc_host *host)
417{
418 int err;
419
420 WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) &&
421 !host->ops->enable_sdio_irq);
422
423 err = device_add(&host->class_dev);
424 if (err)
425 return err;
426
427 led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
428
429#ifdef CONFIG_DEBUG_FS
430 mmc_add_host_debugfs(host);
431#endif
432
433 mmc_start_host(host);
434 mmc_register_pm_notifier(host);
435
436 return 0;
437}
438
439EXPORT_SYMBOL(mmc_add_host);
440
441/**
442 * mmc_remove_host - remove host hardware
443 * @host: mmc host
444 *
445 * Unregister and remove all cards associated with this host,
446 * and power down the MMC bus. No new requests will be issued
447 * after this function has returned.
448 */
449void mmc_remove_host(struct mmc_host *host)
450{
451 mmc_unregister_pm_notifier(host);
452 mmc_stop_host(host);
453
454#ifdef CONFIG_DEBUG_FS
455 mmc_remove_host_debugfs(host);
456#endif
457
458 device_del(&host->class_dev);
459
460 led_trigger_unregister_simple(host->led);
461}
462
463EXPORT_SYMBOL(mmc_remove_host);
464
465/**
466 * mmc_free_host - free the host structure
467 * @host: mmc host
468 *
469 * Free the host once all references to it have been dropped.
470 */
471void mmc_free_host(struct mmc_host *host)
472{
473 mmc_pwrseq_free(host);
474 put_device(&host->class_dev);
475}
476
477EXPORT_SYMBOL(mmc_free_host);