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v4.6
  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_IDR(mmc_host_idr);
 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	idr_remove(&mmc_host_idr, 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
 71void mmc_retune_disable(struct mmc_host *host)
 
 
 72{
 73	host->can_retune = 0;
 74	del_timer_sync(&host->retune_timer);
 75	host->retune_now = 0;
 76	host->need_retune = 0;
 77}
 78
 79void mmc_retune_timer_stop(struct mmc_host *host)
 
 80{
 81	del_timer_sync(&host->retune_timer);
 
 
 
 
 
 
 
 
 
 82}
 83EXPORT_SYMBOL(mmc_retune_timer_stop);
 84
 85void mmc_retune_hold(struct mmc_host *host)
 
 
 
 
 
 
 
 86{
 87	if (!host->hold_retune)
 88		host->retune_now = 1;
 89	host->hold_retune += 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 90}
 91
 92void mmc_retune_release(struct mmc_host *host)
 
 
 
 93{
 94	if (host->hold_retune)
 95		host->hold_retune -= 1;
 96	else
 97		WARN_ON(1);
 98}
 99
100int mmc_retune(struct mmc_host *host)
 
 
 
 
 
 
 
 
101{
102	bool return_to_hs400 = false;
103	int err;
104
105	if (host->retune_now)
106		host->retune_now = 0;
107	else
108		return 0;
 
 
 
 
 
 
 
 
 
 
109
110	if (!host->need_retune || host->doing_retune || !host->card)
111		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
112
113	host->need_retune = 0;
 
 
 
 
 
 
 
 
 
 
114
115	host->doing_retune = 1;
 
 
 
 
 
 
 
116
117	if (host->ios.timing == MMC_TIMING_MMC_HS400) {
118		err = mmc_hs400_to_hs200(host->card);
119		if (err)
120			goto out;
 
 
 
 
 
 
121
122		return_to_hs400 = true;
 
 
 
 
 
 
 
123
124		if (host->ops->prepare_hs400_tuning)
125			host->ops->prepare_hs400_tuning(host, &host->ios);
126	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
127
128	err = mmc_execute_tuning(host->card);
129	if (err)
130		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
131
132	if (return_to_hs400)
133		err = mmc_hs200_to_hs400(host->card);
134out:
135	host->doing_retune = 0;
 
 
 
 
 
 
 
 
136
137	return err;
 
138}
139
140static void mmc_retune_timer(unsigned long data)
141{
142	struct mmc_host *host = (struct mmc_host *)data;
143
144	mmc_retune_needed(host);
 
145}
146
 
 
147/**
148 *	mmc_of_parse() - parse host's device-tree node
149 *	@host: host whose node should be parsed.
150 *
151 * To keep the rest of the MMC subsystem unaware of whether DT has been
152 * used to to instantiate and configure this host instance or not, we
153 * parse the properties and set respective generic mmc-host flags and
154 * parameters.
155 */
156int mmc_of_parse(struct mmc_host *host)
157{
158	struct device_node *np;
159	u32 bus_width;
160	int ret;
161	bool cd_cap_invert, cd_gpio_invert = false;
162	bool ro_cap_invert, ro_gpio_invert = false;
163
164	if (!host->parent || !host->parent->of_node)
165		return 0;
166
167	np = host->parent->of_node;
168
169	/* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
170	if (of_property_read_u32(np, "bus-width", &bus_width) < 0) {
171		dev_dbg(host->parent,
172			"\"bus-width\" property is missing, assuming 1 bit.\n");
173		bus_width = 1;
174	}
175
176	switch (bus_width) {
177	case 8:
178		host->caps |= MMC_CAP_8_BIT_DATA;
179		/* Hosts capable of 8-bit transfers can also do 4 bits */
180	case 4:
181		host->caps |= MMC_CAP_4_BIT_DATA;
182		break;
183	case 1:
184		break;
185	default:
186		dev_err(host->parent,
187			"Invalid \"bus-width\" value %u!\n", bus_width);
188		return -EINVAL;
189	}
190
191	/* f_max is obtained from the optional "max-frequency" property */
192	of_property_read_u32(np, "max-frequency", &host->f_max);
193
194	/*
195	 * Configure CD and WP pins. They are both by default active low to
196	 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
197	 * mmc-gpio helpers are used to attach, configure and use them. If
198	 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
199	 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
200	 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
201	 * is set. If the "non-removable" property is found, the
202	 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
203	 * configuration is performed.
204	 */
205
206	/* Parse Card Detection */
207	if (of_property_read_bool(np, "non-removable")) {
208		host->caps |= MMC_CAP_NONREMOVABLE;
209	} else {
210		cd_cap_invert = of_property_read_bool(np, "cd-inverted");
211
212		if (of_property_read_bool(np, "broken-cd"))
 
 
213			host->caps |= MMC_CAP_NEEDS_POLL;
214
215		ret = mmc_gpiod_request_cd(host, "cd", 0, true,
216					   0, &cd_gpio_invert);
217		if (!ret)
218			dev_info(host->parent, "Got CD GPIO\n");
219		else if (ret != -ENOENT && ret != -ENOSYS)
220			return ret;
221
222		/*
223		 * There are two ways to flag that the CD line is inverted:
224		 * through the cd-inverted flag and by the GPIO line itself
225		 * being inverted from the GPIO subsystem. This is a leftover
226		 * from the times when the GPIO subsystem did not make it
227		 * possible to flag a line as inverted.
228		 *
229		 * If the capability on the host AND the GPIO line are
230		 * both inverted, the end result is that the CD line is
231		 * not inverted.
232		 */
233		if (cd_cap_invert ^ cd_gpio_invert)
 
234			host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
235	}
236
237	/* Parse Write Protection */
238	ro_cap_invert = of_property_read_bool(np, "wp-inverted");
239
240	ret = mmc_gpiod_request_ro(host, "wp", 0, false, 0, &ro_gpio_invert);
241	if (!ret)
242		dev_info(host->parent, "Got WP GPIO\n");
243	else if (ret != -ENOENT && ret != -ENOSYS)
244		return ret;
245
246	if (of_property_read_bool(np, "disable-wp"))
247		host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
248
249	/* See the comment on CD inversion above */
250	if (ro_cap_invert ^ ro_gpio_invert)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
251		host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
252
253	if (of_property_read_bool(np, "cap-sd-highspeed"))
254		host->caps |= MMC_CAP_SD_HIGHSPEED;
255	if (of_property_read_bool(np, "cap-mmc-highspeed"))
256		host->caps |= MMC_CAP_MMC_HIGHSPEED;
257	if (of_property_read_bool(np, "sd-uhs-sdr12"))
258		host->caps |= MMC_CAP_UHS_SDR12;
259	if (of_property_read_bool(np, "sd-uhs-sdr25"))
260		host->caps |= MMC_CAP_UHS_SDR25;
261	if (of_property_read_bool(np, "sd-uhs-sdr50"))
262		host->caps |= MMC_CAP_UHS_SDR50;
263	if (of_property_read_bool(np, "sd-uhs-sdr104"))
264		host->caps |= MMC_CAP_UHS_SDR104;
265	if (of_property_read_bool(np, "sd-uhs-ddr50"))
266		host->caps |= MMC_CAP_UHS_DDR50;
267	if (of_property_read_bool(np, "cap-power-off-card"))
268		host->caps |= MMC_CAP_POWER_OFF_CARD;
269	if (of_property_read_bool(np, "cap-mmc-hw-reset"))
270		host->caps |= MMC_CAP_HW_RESET;
271	if (of_property_read_bool(np, "cap-sdio-irq"))
272		host->caps |= MMC_CAP_SDIO_IRQ;
273	if (of_property_read_bool(np, "full-pwr-cycle"))
274		host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
275	if (of_property_read_bool(np, "keep-power-in-suspend"))
276		host->pm_caps |= MMC_PM_KEEP_POWER;
277	if (of_property_read_bool(np, "wakeup-source") ||
278	    of_property_read_bool(np, "enable-sdio-wakeup")) /* legacy */
279		host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
280	if (of_property_read_bool(np, "mmc-ddr-1_8v"))
281		host->caps |= MMC_CAP_1_8V_DDR;
282	if (of_property_read_bool(np, "mmc-ddr-1_2v"))
283		host->caps |= MMC_CAP_1_2V_DDR;
284	if (of_property_read_bool(np, "mmc-hs200-1_8v"))
285		host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
286	if (of_property_read_bool(np, "mmc-hs200-1_2v"))
287		host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
288	if (of_property_read_bool(np, "mmc-hs400-1_8v"))
289		host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
290	if (of_property_read_bool(np, "mmc-hs400-1_2v"))
291		host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
292
293	host->dsr_req = !of_property_read_u32(np, "dsr", &host->dsr);
294	if (host->dsr_req && (host->dsr & ~0xffff)) {
295		dev_err(host->parent,
296			"device tree specified broken value for DSR: 0x%x, ignoring\n",
297			host->dsr);
298		host->dsr_req = 0;
299	}
300
301	return mmc_pwrseq_alloc(host);
 
 
302}
303
304EXPORT_SYMBOL(mmc_of_parse);
305
306/**
307 *	mmc_alloc_host - initialise the per-host structure.
308 *	@extra: sizeof private data structure
309 *	@dev: pointer to host device model structure
310 *
311 *	Initialise the per-host structure.
312 */
313struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
314{
315	int err;
316	struct mmc_host *host;
317
318	host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
319	if (!host)
320		return NULL;
321
322	/* scanning will be enabled when we're ready */
323	host->rescan_disable = 1;
324	idr_preload(GFP_KERNEL);
325	spin_lock(&mmc_host_lock);
326	err = idr_alloc(&mmc_host_idr, host, 0, 0, GFP_NOWAIT);
327	if (err >= 0)
328		host->index = err;
329	spin_unlock(&mmc_host_lock);
330	idr_preload_end();
331	if (err < 0) {
332		kfree(host);
333		return NULL;
334	}
335
336	dev_set_name(&host->class_dev, "mmc%d", host->index);
337
338	host->parent = dev;
339	host->class_dev.parent = dev;
340	host->class_dev.class = &mmc_host_class;
341	device_initialize(&host->class_dev);
342	device_enable_async_suspend(&host->class_dev);
343
344	if (mmc_gpio_alloc(host)) {
345		put_device(&host->class_dev);
346		return NULL;
347	}
348
349	spin_lock_init(&host->lock);
350	init_waitqueue_head(&host->wq);
351	INIT_DELAYED_WORK(&host->detect, mmc_rescan);
352	setup_timer(&host->retune_timer, mmc_retune_timer, (unsigned long)host);
 
 
353
354	/*
355	 * By default, hosts do not support SGIO or large requests.
356	 * They have to set these according to their abilities.
357	 */
358	host->max_segs = 1;
359	host->max_seg_size = PAGE_SIZE;
360
361	host->max_req_size = PAGE_SIZE;
362	host->max_blk_size = 512;
363	host->max_blk_count = PAGE_SIZE / 512;
364
365	return host;
 
 
 
 
366}
367
368EXPORT_SYMBOL(mmc_alloc_host);
369
370/**
371 *	mmc_add_host - initialise host hardware
372 *	@host: mmc host
373 *
374 *	Register the host with the driver model. The host must be
375 *	prepared to start servicing requests before this function
376 *	completes.
377 */
378int mmc_add_host(struct mmc_host *host)
379{
380	int err;
381
382	WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) &&
383		!host->ops->enable_sdio_irq);
384
385	err = device_add(&host->class_dev);
386	if (err)
387		return err;
388
389	led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
390
391#ifdef CONFIG_DEBUG_FS
392	mmc_add_host_debugfs(host);
393#endif
 
394
395	mmc_start_host(host);
396	mmc_register_pm_notifier(host);
397
398	return 0;
399}
400
401EXPORT_SYMBOL(mmc_add_host);
402
403/**
404 *	mmc_remove_host - remove host hardware
405 *	@host: mmc host
406 *
407 *	Unregister and remove all cards associated with this host,
408 *	and power down the MMC bus. No new requests will be issued
409 *	after this function has returned.
410 */
411void mmc_remove_host(struct mmc_host *host)
412{
413	mmc_unregister_pm_notifier(host);
414	mmc_stop_host(host);
415
416#ifdef CONFIG_DEBUG_FS
417	mmc_remove_host_debugfs(host);
418#endif
419
420	device_del(&host->class_dev);
421
422	led_trigger_unregister_simple(host->led);
 
 
423}
424
425EXPORT_SYMBOL(mmc_remove_host);
426
427/**
428 *	mmc_free_host - free the host structure
429 *	@host: mmc host
430 *
431 *	Free the host once all references to it have been dropped.
432 */
433void mmc_free_host(struct mmc_host *host)
434{
435	mmc_pwrseq_free(host);
 
 
 
436	put_device(&host->class_dev);
437}
438
439EXPORT_SYMBOL(mmc_free_host);
v3.15
  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);