2 * linux/drivers/mmc/core/host.c
4 * Copyright (C) 2003 Russell King, All Rights Reserved.
5 * Copyright (C) 2007-2008 Pierre Ossman
6 * Copyright (C) 2010 Linus Walleij
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.
12 * MMC host class device management
15 #include <linux/device.h>
16 #include <linux/err.h>
17 #include <linux/idr.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>
25 #include <linux/mmc/host.h>
26 #include <linux/mmc/card.h>
27 #include <linux/mmc/slot-gpio.h>
31 #include "slot-gpio.h"
34 #define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
36 static DEFINE_IDA(mmc_host_ida);
37 static DEFINE_SPINLOCK(mmc_host_lock);
39 static void mmc_host_classdev_release(struct device *dev)
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);
48 static struct class mmc_host_class = {
50 .dev_release = mmc_host_classdev_release,
53 int mmc_register_host_class(void)
55 return class_register(&mmc_host_class);
58 void mmc_unregister_host_class(void)
60 class_unregister(&mmc_host_class);
63 void mmc_retune_enable(struct mmc_host *host)
66 if (host->retune_period)
67 mod_timer(&host->retune_timer,
68 jiffies + host->retune_period * HZ);
72 * Pause re-tuning for a small set of operations. The pause begins after the
73 * next command and after first doing re-tuning.
75 void mmc_retune_pause(struct mmc_host *host)
77 if (!host->retune_paused) {
78 host->retune_paused = 1;
79 mmc_retune_needed(host);
80 mmc_retune_hold(host);
83 EXPORT_SYMBOL(mmc_retune_pause);
85 void mmc_retune_unpause(struct mmc_host *host)
87 if (host->retune_paused) {
88 host->retune_paused = 0;
89 mmc_retune_release(host);
92 EXPORT_SYMBOL(mmc_retune_unpause);
94 void mmc_retune_disable(struct mmc_host *host)
96 mmc_retune_unpause(host);
98 del_timer_sync(&host->retune_timer);
100 host->need_retune = 0;
103 void mmc_retune_timer_stop(struct mmc_host *host)
105 del_timer_sync(&host->retune_timer);
107 EXPORT_SYMBOL(mmc_retune_timer_stop);
109 void mmc_retune_hold(struct mmc_host *host)
111 if (!host->hold_retune)
112 host->retune_now = 1;
113 host->hold_retune += 1;
116 void mmc_retune_release(struct mmc_host *host)
118 if (host->hold_retune)
119 host->hold_retune -= 1;
124 int mmc_retune(struct mmc_host *host)
126 bool return_to_hs400 = false;
129 if (host->retune_now)
130 host->retune_now = 0;
134 if (!host->need_retune || host->doing_retune || !host->card)
137 host->need_retune = 0;
139 host->doing_retune = 1;
141 if (host->ios.timing == MMC_TIMING_MMC_HS400) {
142 err = mmc_hs400_to_hs200(host->card);
146 return_to_hs400 = true;
148 if (host->ops->prepare_hs400_tuning)
149 host->ops->prepare_hs400_tuning(host, &host->ios);
152 err = mmc_execute_tuning(host->card);
157 err = mmc_hs200_to_hs400(host->card);
159 host->doing_retune = 0;
164 static void mmc_retune_timer(unsigned long data)
166 struct mmc_host *host = (struct mmc_host *)data;
168 mmc_retune_needed(host);
172 * mmc_of_parse() - parse host's device-tree node
173 * @host: host whose node should be parsed.
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
180 int mmc_of_parse(struct mmc_host *host)
182 struct device *dev = host->parent;
185 bool cd_cap_invert, cd_gpio_invert = false;
186 bool ro_cap_invert, ro_gpio_invert = false;
188 if (!dev || !dev_fwnode(dev))
191 /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
192 if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) {
193 dev_dbg(host->parent,
194 "\"bus-width\" property is missing, assuming 1 bit.\n");
200 host->caps |= MMC_CAP_8_BIT_DATA;
201 /* Hosts capable of 8-bit transfers can also do 4 bits */
203 host->caps |= MMC_CAP_4_BIT_DATA;
208 dev_err(host->parent,
209 "Invalid \"bus-width\" value %u!\n", bus_width);
213 /* f_max is obtained from the optional "max-frequency" property */
214 device_property_read_u32(dev, "max-frequency", &host->f_max);
217 * Configure CD and WP pins. They are both by default active low to
218 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
219 * mmc-gpio helpers are used to attach, configure and use them. If
220 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
221 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
222 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
223 * is set. If the "non-removable" property is found, the
224 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
225 * configuration is performed.
228 /* Parse Card Detection */
229 if (device_property_read_bool(dev, "non-removable")) {
230 host->caps |= MMC_CAP_NONREMOVABLE;
232 cd_cap_invert = device_property_read_bool(dev, "cd-inverted");
234 if (device_property_read_bool(dev, "broken-cd"))
235 host->caps |= MMC_CAP_NEEDS_POLL;
237 ret = mmc_gpiod_request_cd(host, "cd", 0, true,
240 dev_info(host->parent, "Got CD GPIO\n");
241 else if (ret != -ENOENT && ret != -ENOSYS)
245 * There are two ways to flag that the CD line is inverted:
246 * through the cd-inverted flag and by the GPIO line itself
247 * being inverted from the GPIO subsystem. This is a leftover
248 * from the times when the GPIO subsystem did not make it
249 * possible to flag a line as inverted.
251 * If the capability on the host AND the GPIO line are
252 * both inverted, the end result is that the CD line is
255 if (cd_cap_invert ^ cd_gpio_invert)
256 host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
259 /* Parse Write Protection */
260 ro_cap_invert = device_property_read_bool(dev, "wp-inverted");
262 ret = mmc_gpiod_request_ro(host, "wp", 0, false, 0, &ro_gpio_invert);
264 dev_info(host->parent, "Got WP GPIO\n");
265 else if (ret != -ENOENT && ret != -ENOSYS)
268 if (device_property_read_bool(dev, "disable-wp"))
269 host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
271 /* See the comment on CD inversion above */
272 if (ro_cap_invert ^ ro_gpio_invert)
273 host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
275 if (device_property_read_bool(dev, "cap-sd-highspeed"))
276 host->caps |= MMC_CAP_SD_HIGHSPEED;
277 if (device_property_read_bool(dev, "cap-mmc-highspeed"))
278 host->caps |= MMC_CAP_MMC_HIGHSPEED;
279 if (device_property_read_bool(dev, "sd-uhs-sdr12"))
280 host->caps |= MMC_CAP_UHS_SDR12;
281 if (device_property_read_bool(dev, "sd-uhs-sdr25"))
282 host->caps |= MMC_CAP_UHS_SDR25;
283 if (device_property_read_bool(dev, "sd-uhs-sdr50"))
284 host->caps |= MMC_CAP_UHS_SDR50;
285 if (device_property_read_bool(dev, "sd-uhs-sdr104"))
286 host->caps |= MMC_CAP_UHS_SDR104;
287 if (device_property_read_bool(dev, "sd-uhs-ddr50"))
288 host->caps |= MMC_CAP_UHS_DDR50;
289 if (device_property_read_bool(dev, "cap-power-off-card"))
290 host->caps |= MMC_CAP_POWER_OFF_CARD;
291 if (device_property_read_bool(dev, "cap-mmc-hw-reset"))
292 host->caps |= MMC_CAP_HW_RESET;
293 if (device_property_read_bool(dev, "cap-sdio-irq"))
294 host->caps |= MMC_CAP_SDIO_IRQ;
295 if (device_property_read_bool(dev, "full-pwr-cycle"))
296 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
297 if (device_property_read_bool(dev, "keep-power-in-suspend"))
298 host->pm_caps |= MMC_PM_KEEP_POWER;
299 if (device_property_read_bool(dev, "wakeup-source") ||
300 device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
301 host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
302 if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
303 host->caps |= MMC_CAP_1_8V_DDR;
304 if (device_property_read_bool(dev, "mmc-ddr-1_2v"))
305 host->caps |= MMC_CAP_1_2V_DDR;
306 if (device_property_read_bool(dev, "mmc-hs200-1_8v"))
307 host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
308 if (device_property_read_bool(dev, "mmc-hs200-1_2v"))
309 host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
310 if (device_property_read_bool(dev, "mmc-hs400-1_8v"))
311 host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
312 if (device_property_read_bool(dev, "mmc-hs400-1_2v"))
313 host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
314 if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe"))
315 host->caps2 |= MMC_CAP2_HS400_ES;
316 if (device_property_read_bool(dev, "no-sdio"))
317 host->caps2 |= MMC_CAP2_NO_SDIO;
318 if (device_property_read_bool(dev, "no-sd"))
319 host->caps2 |= MMC_CAP2_NO_SD;
320 if (device_property_read_bool(dev, "no-mmc"))
321 host->caps2 |= MMC_CAP2_NO_MMC;
323 host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr);
324 if (host->dsr_req && (host->dsr & ~0xffff)) {
325 dev_err(host->parent,
326 "device tree specified broken value for DSR: 0x%x, ignoring\n",
331 return mmc_pwrseq_alloc(host);
334 EXPORT_SYMBOL(mmc_of_parse);
337 * mmc_alloc_host - initialise the per-host structure.
338 * @extra: sizeof private data structure
339 * @dev: pointer to host device model structure
341 * Initialise the per-host structure.
343 struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
346 struct mmc_host *host;
348 host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
352 /* scanning will be enabled when we're ready */
353 host->rescan_disable = 1;
356 if (!ida_pre_get(&mmc_host_ida, GFP_KERNEL)) {
361 spin_lock(&mmc_host_lock);
362 err = ida_get_new(&mmc_host_ida, &host->index);
363 spin_unlock(&mmc_host_lock);
365 if (err == -EAGAIN) {
372 dev_set_name(&host->class_dev, "mmc%d", host->index);
375 host->class_dev.parent = dev;
376 host->class_dev.class = &mmc_host_class;
377 device_initialize(&host->class_dev);
378 device_enable_async_suspend(&host->class_dev);
380 if (mmc_gpio_alloc(host)) {
381 put_device(&host->class_dev);
385 spin_lock_init(&host->lock);
386 init_waitqueue_head(&host->wq);
387 INIT_DELAYED_WORK(&host->detect, mmc_rescan);
388 setup_timer(&host->retune_timer, mmc_retune_timer, (unsigned long)host);
391 * By default, hosts do not support SGIO or large requests.
392 * They have to set these according to their abilities.
395 host->max_seg_size = PAGE_SIZE;
397 host->max_req_size = PAGE_SIZE;
398 host->max_blk_size = 512;
399 host->max_blk_count = PAGE_SIZE / 512;
404 EXPORT_SYMBOL(mmc_alloc_host);
406 static int mmc_validate_host_caps(struct mmc_host *host)
408 if (host->caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) {
409 dev_warn(host->parent, "missing ->enable_sdio_irq() ops\n");
417 * mmc_add_host - initialise host hardware
420 * Register the host with the driver model. The host must be
421 * prepared to start servicing requests before this function
424 int mmc_add_host(struct mmc_host *host)
428 err = mmc_validate_host_caps(host);
432 err = device_add(&host->class_dev);
436 led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
438 #ifdef CONFIG_DEBUG_FS
439 mmc_add_host_debugfs(host);
442 mmc_start_host(host);
443 mmc_register_pm_notifier(host);
448 EXPORT_SYMBOL(mmc_add_host);
451 * mmc_remove_host - remove host hardware
454 * Unregister and remove all cards associated with this host,
455 * and power down the MMC bus. No new requests will be issued
456 * after this function has returned.
458 void mmc_remove_host(struct mmc_host *host)
460 mmc_unregister_pm_notifier(host);
463 #ifdef CONFIG_DEBUG_FS
464 mmc_remove_host_debugfs(host);
467 device_del(&host->class_dev);
469 led_trigger_unregister_simple(host->led);
472 EXPORT_SYMBOL(mmc_remove_host);
475 * mmc_free_host - free the host structure
478 * Free the host once all references to it have been dropped.
480 void mmc_free_host(struct mmc_host *host)
482 mmc_pwrseq_free(host);
483 put_device(&host->class_dev);
486 EXPORT_SYMBOL(mmc_free_host);