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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
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);
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/pagemap.h>
19#include <linux/leds.h>
20#include <linux/slab.h>
21#include <linux/suspend.h>
22
23#include <linux/mmc/host.h>
24#include <linux/mmc/card.h>
25
26#include "core.h"
27#include "host.h"
28
29#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
30
31static void mmc_host_classdev_release(struct device *dev)
32{
33 struct mmc_host *host = cls_dev_to_mmc_host(dev);
34 kfree(host);
35}
36
37static struct class mmc_host_class = {
38 .name = "mmc_host",
39 .dev_release = mmc_host_classdev_release,
40};
41
42int mmc_register_host_class(void)
43{
44 return class_register(&mmc_host_class);
45}
46
47void mmc_unregister_host_class(void)
48{
49 class_unregister(&mmc_host_class);
50}
51
52static DEFINE_IDR(mmc_host_idr);
53static DEFINE_SPINLOCK(mmc_host_lock);
54
55#ifdef CONFIG_MMC_CLKGATE
56
57/*
58 * Enabling clock gating will make the core call out to the host
59 * once up and once down when it performs a request or card operation
60 * intermingled in any fashion. The driver will see this through
61 * set_ios() operations with ios.clock field set to 0 to gate (disable)
62 * the block clock, and to the old frequency to enable it again.
63 */
64static void mmc_host_clk_gate_delayed(struct mmc_host *host)
65{
66 unsigned long tick_ns;
67 unsigned long freq = host->ios.clock;
68 unsigned long flags;
69
70 if (!freq) {
71 pr_debug("%s: frequency set to 0 in disable function, "
72 "this means the clock is already disabled.\n",
73 mmc_hostname(host));
74 return;
75 }
76 /*
77 * New requests may have appeared while we were scheduling,
78 * then there is no reason to delay the check before
79 * clk_disable().
80 */
81 spin_lock_irqsave(&host->clk_lock, flags);
82
83 /*
84 * Delay n bus cycles (at least 8 from MMC spec) before attempting
85 * to disable the MCI block clock. The reference count may have
86 * gone up again after this delay due to rescheduling!
87 */
88 if (!host->clk_requests) {
89 spin_unlock_irqrestore(&host->clk_lock, flags);
90 tick_ns = DIV_ROUND_UP(1000000000, freq);
91 ndelay(host->clk_delay * tick_ns);
92 } else {
93 /* New users appeared while waiting for this work */
94 spin_unlock_irqrestore(&host->clk_lock, flags);
95 return;
96 }
97 mutex_lock(&host->clk_gate_mutex);
98 spin_lock_irqsave(&host->clk_lock, flags);
99 if (!host->clk_requests) {
100 spin_unlock_irqrestore(&host->clk_lock, flags);
101 /* This will set host->ios.clock to 0 */
102 mmc_gate_clock(host);
103 spin_lock_irqsave(&host->clk_lock, flags);
104 pr_debug("%s: gated MCI clock\n", mmc_hostname(host));
105 }
106 spin_unlock_irqrestore(&host->clk_lock, flags);
107 mutex_unlock(&host->clk_gate_mutex);
108}
109
110/*
111 * Internal work. Work to disable the clock at some later point.
112 */
113static void mmc_host_clk_gate_work(struct work_struct *work)
114{
115 struct mmc_host *host = container_of(work, struct mmc_host,
116 clk_gate_work);
117
118 mmc_host_clk_gate_delayed(host);
119}
120
121/**
122 * mmc_host_clk_hold - ungate hardware MCI clocks
123 * @host: host to ungate.
124 *
125 * Makes sure the host ios.clock is restored to a non-zero value
126 * past this call. Increase clock reference count and ungate clock
127 * if we're the first user.
128 */
129void mmc_host_clk_hold(struct mmc_host *host)
130{
131 unsigned long flags;
132
133 mutex_lock(&host->clk_gate_mutex);
134 spin_lock_irqsave(&host->clk_lock, flags);
135 if (host->clk_gated) {
136 spin_unlock_irqrestore(&host->clk_lock, flags);
137 mmc_ungate_clock(host);
138 spin_lock_irqsave(&host->clk_lock, flags);
139 pr_debug("%s: ungated MCI clock\n", mmc_hostname(host));
140 }
141 host->clk_requests++;
142 spin_unlock_irqrestore(&host->clk_lock, flags);
143 mutex_unlock(&host->clk_gate_mutex);
144}
145
146/**
147 * mmc_host_may_gate_card - check if this card may be gated
148 * @card: card to check.
149 */
150static bool mmc_host_may_gate_card(struct mmc_card *card)
151{
152 /* If there is no card we may gate it */
153 if (!card)
154 return true;
155 /*
156 * Don't gate SDIO cards! These need to be clocked at all times
157 * since they may be independent systems generating interrupts
158 * and other events. The clock requests counter from the core will
159 * go down to zero since the core does not need it, but we will not
160 * gate the clock, because there is somebody out there that may still
161 * be using it.
162 */
163 return !(card->quirks & MMC_QUIRK_BROKEN_CLK_GATING);
164}
165
166/**
167 * mmc_host_clk_release - gate off hardware MCI clocks
168 * @host: host to gate.
169 *
170 * Calls the host driver with ios.clock set to zero as often as possible
171 * in order to gate off hardware MCI clocks. Decrease clock reference
172 * count and schedule disabling of clock.
173 */
174void mmc_host_clk_release(struct mmc_host *host)
175{
176 unsigned long flags;
177
178 spin_lock_irqsave(&host->clk_lock, flags);
179 host->clk_requests--;
180 if (mmc_host_may_gate_card(host->card) &&
181 !host->clk_requests)
182 queue_work(system_nrt_wq, &host->clk_gate_work);
183 spin_unlock_irqrestore(&host->clk_lock, flags);
184}
185
186/**
187 * mmc_host_clk_rate - get current clock frequency setting
188 * @host: host to get the clock frequency for.
189 *
190 * Returns current clock frequency regardless of gating.
191 */
192unsigned int mmc_host_clk_rate(struct mmc_host *host)
193{
194 unsigned long freq;
195 unsigned long flags;
196
197 spin_lock_irqsave(&host->clk_lock, flags);
198 if (host->clk_gated)
199 freq = host->clk_old;
200 else
201 freq = host->ios.clock;
202 spin_unlock_irqrestore(&host->clk_lock, flags);
203 return freq;
204}
205
206/**
207 * mmc_host_clk_init - set up clock gating code
208 * @host: host with potential clock to control
209 */
210static inline void mmc_host_clk_init(struct mmc_host *host)
211{
212 host->clk_requests = 0;
213 /* Hold MCI clock for 8 cycles by default */
214 host->clk_delay = 8;
215 host->clk_gated = false;
216 INIT_WORK(&host->clk_gate_work, mmc_host_clk_gate_work);
217 spin_lock_init(&host->clk_lock);
218 mutex_init(&host->clk_gate_mutex);
219}
220
221/**
222 * mmc_host_clk_exit - shut down clock gating code
223 * @host: host with potential clock to control
224 */
225static inline void mmc_host_clk_exit(struct mmc_host *host)
226{
227 /*
228 * Wait for any outstanding gate and then make sure we're
229 * ungated before exiting.
230 */
231 if (cancel_work_sync(&host->clk_gate_work))
232 mmc_host_clk_gate_delayed(host);
233 if (host->clk_gated)
234 mmc_host_clk_hold(host);
235 /* There should be only one user now */
236 WARN_ON(host->clk_requests > 1);
237}
238
239#else
240
241static inline void mmc_host_clk_init(struct mmc_host *host)
242{
243}
244
245static inline void mmc_host_clk_exit(struct mmc_host *host)
246{
247}
248
249#endif
250
251/**
252 * mmc_alloc_host - initialise the per-host structure.
253 * @extra: sizeof private data structure
254 * @dev: pointer to host device model structure
255 *
256 * Initialise the per-host structure.
257 */
258struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
259{
260 int err;
261 struct mmc_host *host;
262
263 if (!idr_pre_get(&mmc_host_idr, GFP_KERNEL))
264 return NULL;
265
266 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
267 if (!host)
268 return NULL;
269
270 spin_lock(&mmc_host_lock);
271 err = idr_get_new(&mmc_host_idr, host, &host->index);
272 spin_unlock(&mmc_host_lock);
273 if (err)
274 goto free;
275
276 dev_set_name(&host->class_dev, "mmc%d", host->index);
277
278 host->parent = dev;
279 host->class_dev.parent = dev;
280 host->class_dev.class = &mmc_host_class;
281 device_initialize(&host->class_dev);
282
283 mmc_host_clk_init(host);
284
285 spin_lock_init(&host->lock);
286 init_waitqueue_head(&host->wq);
287 INIT_DELAYED_WORK(&host->detect, mmc_rescan);
288 INIT_DELAYED_WORK_DEFERRABLE(&host->disable, mmc_host_deeper_disable);
289#ifdef CONFIG_PM
290 host->pm_notify.notifier_call = mmc_pm_notify;
291#endif
292
293 /*
294 * By default, hosts do not support SGIO or large requests.
295 * They have to set these according to their abilities.
296 */
297 host->max_segs = 1;
298 host->max_seg_size = PAGE_CACHE_SIZE;
299
300 host->max_req_size = PAGE_CACHE_SIZE;
301 host->max_blk_size = 512;
302 host->max_blk_count = PAGE_CACHE_SIZE / 512;
303
304 return host;
305
306free:
307 kfree(host);
308 return NULL;
309}
310
311EXPORT_SYMBOL(mmc_alloc_host);
312
313/**
314 * mmc_add_host - initialise host hardware
315 * @host: mmc host
316 *
317 * Register the host with the driver model. The host must be
318 * prepared to start servicing requests before this function
319 * completes.
320 */
321int mmc_add_host(struct mmc_host *host)
322{
323 int err;
324
325 WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) &&
326 !host->ops->enable_sdio_irq);
327
328 err = device_add(&host->class_dev);
329 if (err)
330 return err;
331
332 led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
333
334#ifdef CONFIG_DEBUG_FS
335 mmc_add_host_debugfs(host);
336#endif
337
338 mmc_start_host(host);
339 register_pm_notifier(&host->pm_notify);
340
341 return 0;
342}
343
344EXPORT_SYMBOL(mmc_add_host);
345
346/**
347 * mmc_remove_host - remove host hardware
348 * @host: mmc host
349 *
350 * Unregister and remove all cards associated with this host,
351 * and power down the MMC bus. No new requests will be issued
352 * after this function has returned.
353 */
354void mmc_remove_host(struct mmc_host *host)
355{
356 unregister_pm_notifier(&host->pm_notify);
357 mmc_stop_host(host);
358
359#ifdef CONFIG_DEBUG_FS
360 mmc_remove_host_debugfs(host);
361#endif
362
363 device_del(&host->class_dev);
364
365 led_trigger_unregister_simple(host->led);
366
367 mmc_host_clk_exit(host);
368}
369
370EXPORT_SYMBOL(mmc_remove_host);
371
372/**
373 * mmc_free_host - free the host structure
374 * @host: mmc host
375 *
376 * Free the host once all references to it have been dropped.
377 */
378void mmc_free_host(struct mmc_host *host)
379{
380 spin_lock(&mmc_host_lock);
381 idr_remove(&mmc_host_idr, host->index);
382 spin_unlock(&mmc_host_lock);
383
384 put_device(&host->class_dev);
385}
386
387EXPORT_SYMBOL(mmc_free_host);