root/drivers/mmc/core/host.c

DEFINITIONS

1. mmc_host_classdev_release
2. mmc_register_host_class
3. mmc_unregister_host_class
4. mmc_retune_enable
5. mmc_retune_pause
6. mmc_retune_unpause
7. mmc_retune_disable
8. mmc_retune_timer_stop
9. mmc_retune_hold
10. mmc_retune_release
11. mmc_retune
12. mmc_retune_timer
13. mmc_of_parse
14. mmc_of_parse_voltage
15. mmc_alloc_host
16. mmc_add_host
17. mmc_remove_host
18. mmc_free_host

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/drivers/mmc/core/host.c
   4  *
   5  *  Copyright (C) 2003 Russell King, All Rights Reserved.
   6  *  Copyright (C) 2007-2008 Pierre Ossman
   7  *  Copyright (C) 2010 Linus Walleij
   8  *
   9  *  MMC host class device management
  10  */
  11 
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/idr.h>
  15 #include <linux/of.h>
  16 #include <linux/of_gpio.h>
  17 #include <linux/pagemap.h>
  18 #include <linux/export.h>
  19 #include <linux/leds.h>
  20 #include <linux/slab.h>
  21 
  22 #include <linux/mmc/host.h>
  23 #include <linux/mmc/card.h>
  24 #include <linux/mmc/slot-gpio.h>
  25 
  26 #include "core.h"
  27 #include "host.h"
  28 #include "slot-gpio.h"
  29 #include "pwrseq.h"
  30 #include "sdio_ops.h"
  31 
  32 #define cls_dev_to_mmc_host(d)  container_of(d, struct mmc_host, class_dev)
  33 
  34 static DEFINE_IDA(mmc_host_ida);
  35 
  36 static void mmc_host_classdev_release(struct device *dev)
  37 {
  38         struct mmc_host *host = cls_dev_to_mmc_host(dev);
  39         ida_simple_remove(&mmc_host_ida, host->index);
  40         kfree(host);
  41 }
  42 
  43 static struct class mmc_host_class = {
  44         .name           = "mmc_host",
  45         .dev_release    = mmc_host_classdev_release,
  46 };
  47 
  48 int mmc_register_host_class(void)
  49 {
  50         return class_register(&mmc_host_class);
  51 }
  52 
  53 void mmc_unregister_host_class(void)
  54 {
  55         class_unregister(&mmc_host_class);
  56 }
  57 
  58 void mmc_retune_enable(struct mmc_host *host)
  59 {
  60         host->can_retune = 1;
  61         if (host->retune_period)
  62                 mod_timer(&host->retune_timer,
  63                           jiffies + host->retune_period * HZ);
  64 }
  65 
  66 /*
  67  * Pause re-tuning for a small set of operations.  The pause begins after the
  68  * next command and after first doing re-tuning.
  69  */
  70 void mmc_retune_pause(struct mmc_host *host)
  71 {
  72         if (!host->retune_paused) {
  73                 host->retune_paused = 1;
  74                 mmc_retune_needed(host);
  75                 mmc_retune_hold(host);
  76         }
  77 }
  78 EXPORT_SYMBOL(mmc_retune_pause);
  79 
  80 void mmc_retune_unpause(struct mmc_host *host)
  81 {
  82         if (host->retune_paused) {
  83                 host->retune_paused = 0;
  84                 mmc_retune_release(host);
  85         }
  86 }
  87 EXPORT_SYMBOL(mmc_retune_unpause);
  88 
  89 void mmc_retune_disable(struct mmc_host *host)
  90 {
  91         mmc_retune_unpause(host);
  92         host->can_retune = 0;
  93         del_timer_sync(&host->retune_timer);
  94         host->retune_now = 0;
  95         host->need_retune = 0;
  96 }
  97 
  98 void mmc_retune_timer_stop(struct mmc_host *host)
  99 {
 100         del_timer_sync(&host->retune_timer);
 101 }
 102 EXPORT_SYMBOL(mmc_retune_timer_stop);
 103 
 104 void mmc_retune_hold(struct mmc_host *host)
 105 {
 106         if (!host->hold_retune)
 107                 host->retune_now = 1;
 108         host->hold_retune += 1;
 109 }
 110 
 111 void mmc_retune_release(struct mmc_host *host)
 112 {
 113         if (host->hold_retune)
 114                 host->hold_retune -= 1;
 115         else
 116                 WARN_ON(1);
 117 }
 118 EXPORT_SYMBOL(mmc_retune_release);
 119 
 120 int mmc_retune(struct mmc_host *host)
 121 {
 122         bool return_to_hs400 = false;
 123         int err;
 124 
 125         if (host->retune_now)
 126                 host->retune_now = 0;
 127         else
 128                 return 0;
 129 
 130         if (!host->need_retune || host->doing_retune || !host->card)
 131                 return 0;
 132 
 133         host->need_retune = 0;
 134 
 135         host->doing_retune = 1;
 136 
 137         if (host->ios.timing == MMC_TIMING_MMC_HS400) {
 138                 err = mmc_hs400_to_hs200(host->card);
 139                 if (err)
 140                         goto out;
 141 
 142                 return_to_hs400 = true;
 143         }
 144 
 145         err = mmc_execute_tuning(host->card);
 146         if (err)
 147                 goto out;
 148 
 149         if (return_to_hs400)
 150                 err = mmc_hs200_to_hs400(host->card);
 151 out:
 152         host->doing_retune = 0;
 153 
 154         return err;
 155 }
 156 
 157 static void mmc_retune_timer(struct timer_list *t)
 158 {
 159         struct mmc_host *host = from_timer(host, t, retune_timer);
 160 
 161         mmc_retune_needed(host);
 162 }
 163 
 164 /**
 165  *      mmc_of_parse() - parse host's device-tree node
 166  *      @host: host whose node should be parsed.
 167  *
 168  * To keep the rest of the MMC subsystem unaware of whether DT has been
 169  * used to to instantiate and configure this host instance or not, we
 170  * parse the properties and set respective generic mmc-host flags and
 171  * parameters.
 172  */
 173 int mmc_of_parse(struct mmc_host *host)
 174 {
 175         struct device *dev = host->parent;
 176         u32 bus_width, drv_type, cd_debounce_delay_ms;
 177         int ret;
 178         bool cd_cap_invert, cd_gpio_invert = false;
 179 
 180         if (!dev || !dev_fwnode(dev))
 181                 return 0;
 182 
 183         /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
 184         if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) {
 185                 dev_dbg(host->parent,
 186                         "\"bus-width\" property is missing, assuming 1 bit.\n");
 187                 bus_width = 1;
 188         }
 189 
 190         switch (bus_width) {
 191         case 8:
 192                 host->caps |= MMC_CAP_8_BIT_DATA;
 193                 /* fall through - Hosts capable of 8-bit can also do 4 bits */
 194         case 4:
 195                 host->caps |= MMC_CAP_4_BIT_DATA;
 196                 break;
 197         case 1:
 198                 break;
 199         default:
 200                 dev_err(host->parent,
 201                         "Invalid \"bus-width\" value %u!\n", bus_width);
 202                 return -EINVAL;
 203         }
 204 
 205         /* f_max is obtained from the optional "max-frequency" property */
 206         device_property_read_u32(dev, "max-frequency", &host->f_max);
 207 
 208         /*
 209          * Configure CD and WP pins. They are both by default active low to
 210          * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
 211          * mmc-gpio helpers are used to attach, configure and use them. If
 212          * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
 213          * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
 214          * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
 215          * is set. If the "non-removable" property is found, the
 216          * MMC_CAP_NONREMOVABLE capability is set and no card-detection
 217          * configuration is performed.
 218          */
 219 
 220         /* Parse Card Detection */
 221         if (device_property_read_bool(dev, "non-removable")) {
 222                 host->caps |= MMC_CAP_NONREMOVABLE;
 223         } else {
 224                 cd_cap_invert = device_property_read_bool(dev, "cd-inverted");
 225 
 226                 if (device_property_read_u32(dev, "cd-debounce-delay-ms",
 227                                              &cd_debounce_delay_ms))
 228                         cd_debounce_delay_ms = 200;
 229 
 230                 if (device_property_read_bool(dev, "broken-cd"))
 231                         host->caps |= MMC_CAP_NEEDS_POLL;
 232 
 233                 ret = mmc_gpiod_request_cd(host, "cd", 0, false,
 234                                            cd_debounce_delay_ms * 1000,
 235                                            &cd_gpio_invert);
 236                 if (!ret)
 237                         dev_info(host->parent, "Got CD GPIO\n");
 238                 else if (ret != -ENOENT && ret != -ENOSYS)
 239                         return ret;
 240 
 241                 /*
 242                  * There are two ways to flag that the CD line is inverted:
 243                  * through the cd-inverted flag and by the GPIO line itself
 244                  * being inverted from the GPIO subsystem. This is a leftover
 245                  * from the times when the GPIO subsystem did not make it
 246                  * possible to flag a line as inverted.
 247                  *
 248                  * If the capability on the host AND the GPIO line are
 249                  * both inverted, the end result is that the CD line is
 250                  * not inverted.
 251                  */
 252                 if (cd_cap_invert ^ cd_gpio_invert)
 253                         host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
 254         }
 255 
 256         /* Parse Write Protection */
 257 
 258         if (device_property_read_bool(dev, "wp-inverted"))
 259                 host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
 260 
 261         ret = mmc_gpiod_request_ro(host, "wp", 0, 0, NULL);
 262         if (!ret)
 263                 dev_info(host->parent, "Got WP GPIO\n");
 264         else if (ret != -ENOENT && ret != -ENOSYS)
 265                 return ret;
 266 
 267         if (device_property_read_bool(dev, "disable-wp"))
 268                 host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
 269 
 270         if (device_property_read_bool(dev, "cap-sd-highspeed"))
 271                 host->caps |= MMC_CAP_SD_HIGHSPEED;
 272         if (device_property_read_bool(dev, "cap-mmc-highspeed"))
 273                 host->caps |= MMC_CAP_MMC_HIGHSPEED;
 274         if (device_property_read_bool(dev, "sd-uhs-sdr12"))
 275                 host->caps |= MMC_CAP_UHS_SDR12;
 276         if (device_property_read_bool(dev, "sd-uhs-sdr25"))
 277                 host->caps |= MMC_CAP_UHS_SDR25;
 278         if (device_property_read_bool(dev, "sd-uhs-sdr50"))
 279                 host->caps |= MMC_CAP_UHS_SDR50;
 280         if (device_property_read_bool(dev, "sd-uhs-sdr104"))
 281                 host->caps |= MMC_CAP_UHS_SDR104;
 282         if (device_property_read_bool(dev, "sd-uhs-ddr50"))
 283                 host->caps |= MMC_CAP_UHS_DDR50;
 284         if (device_property_read_bool(dev, "cap-power-off-card"))
 285                 host->caps |= MMC_CAP_POWER_OFF_CARD;
 286         if (device_property_read_bool(dev, "cap-mmc-hw-reset"))
 287                 host->caps |= MMC_CAP_HW_RESET;
 288         if (device_property_read_bool(dev, "cap-sdio-irq"))
 289                 host->caps |= MMC_CAP_SDIO_IRQ;
 290         if (device_property_read_bool(dev, "full-pwr-cycle"))
 291                 host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
 292         if (device_property_read_bool(dev, "keep-power-in-suspend"))
 293                 host->pm_caps |= MMC_PM_KEEP_POWER;
 294         if (device_property_read_bool(dev, "wakeup-source") ||
 295             device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
 296                 host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
 297         if (device_property_read_bool(dev, "mmc-ddr-3_3v"))
 298                 host->caps |= MMC_CAP_3_3V_DDR;
 299         if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
 300                 host->caps |= MMC_CAP_1_8V_DDR;
 301         if (device_property_read_bool(dev, "mmc-ddr-1_2v"))
 302                 host->caps |= MMC_CAP_1_2V_DDR;
 303         if (device_property_read_bool(dev, "mmc-hs200-1_8v"))
 304                 host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
 305         if (device_property_read_bool(dev, "mmc-hs200-1_2v"))
 306                 host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
 307         if (device_property_read_bool(dev, "mmc-hs400-1_8v"))
 308                 host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
 309         if (device_property_read_bool(dev, "mmc-hs400-1_2v"))
 310                 host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
 311         if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe"))
 312                 host->caps2 |= MMC_CAP2_HS400_ES;
 313         if (device_property_read_bool(dev, "no-sdio"))
 314                 host->caps2 |= MMC_CAP2_NO_SDIO;
 315         if (device_property_read_bool(dev, "no-sd"))
 316                 host->caps2 |= MMC_CAP2_NO_SD;
 317         if (device_property_read_bool(dev, "no-mmc"))
 318                 host->caps2 |= MMC_CAP2_NO_MMC;
 319 
 320         /* Must be after "non-removable" check */
 321         if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) {
 322                 if (host->caps & MMC_CAP_NONREMOVABLE)
 323                         host->fixed_drv_type = drv_type;
 324                 else
 325                         dev_err(host->parent,
 326                                 "can't use fixed driver type, media is removable\n");
 327         }
 328 
 329         host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr);
 330         if (host->dsr_req && (host->dsr & ~0xffff)) {
 331                 dev_err(host->parent,
 332                         "device tree specified broken value for DSR: 0x%x, ignoring\n",
 333                         host->dsr);
 334                 host->dsr_req = 0;
 335         }
 336 
 337         device_property_read_u32(dev, "post-power-on-delay-ms",
 338                                  &host->ios.power_delay_ms);
 339 
 340         return mmc_pwrseq_alloc(host);
 341 }
 342 
 343 EXPORT_SYMBOL(mmc_of_parse);
 344 
 345 /**
 346  * mmc_of_parse_voltage - return mask of supported voltages
 347  * @np: The device node need to be parsed.
 348  * @mask: mask of voltages available for MMC/SD/SDIO
 349  *
 350  * Parse the "voltage-ranges" DT property, returning zero if it is not
 351  * found, negative errno if the voltage-range specification is invalid,
 352  * or one if the voltage-range is specified and successfully parsed.
 353  */
 354 int mmc_of_parse_voltage(struct device_node *np, u32 *mask)
 355 {
 356         const u32 *voltage_ranges;
 357         int num_ranges, i;
 358 
 359         voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
 360         if (!voltage_ranges) {
 361                 pr_debug("%pOF: voltage-ranges unspecified\n", np);
 362                 return 0;
 363         }
 364         num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
 365         if (!num_ranges) {
 366                 pr_err("%pOF: voltage-ranges empty\n", np);
 367                 return -EINVAL;
 368         }
 369 
 370         for (i = 0; i < num_ranges; i++) {
 371                 const int j = i * 2;
 372                 u32 ocr_mask;
 373 
 374                 ocr_mask = mmc_vddrange_to_ocrmask(
 375                                 be32_to_cpu(voltage_ranges[j]),
 376                                 be32_to_cpu(voltage_ranges[j + 1]));
 377                 if (!ocr_mask) {
 378                         pr_err("%pOF: voltage-range #%d is invalid\n",
 379                                 np, i);
 380                         return -EINVAL;
 381                 }
 382                 *mask |= ocr_mask;
 383         }
 384 
 385         return 1;
 386 }
 387 EXPORT_SYMBOL(mmc_of_parse_voltage);
 388 
 389 /**
 390  *      mmc_alloc_host - initialise the per-host structure.
 391  *      @extra: sizeof private data structure
 392  *      @dev: pointer to host device model structure
 393  *
 394  *      Initialise the per-host structure.
 395  */
 396 struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
 397 {
 398         int err;
 399         struct mmc_host *host;
 400 
 401         host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
 402         if (!host)
 403                 return NULL;
 404 
 405         /* scanning will be enabled when we're ready */
 406         host->rescan_disable = 1;
 407 
 408         err = ida_simple_get(&mmc_host_ida, 0, 0, GFP_KERNEL);
 409         if (err < 0) {
 410                 kfree(host);
 411                 return NULL;
 412         }
 413 
 414         host->index = err;
 415 
 416         dev_set_name(&host->class_dev, "mmc%d", host->index);
 417 
 418         host->parent = dev;
 419         host->class_dev.parent = dev;
 420         host->class_dev.class = &mmc_host_class;
 421         device_initialize(&host->class_dev);
 422         device_enable_async_suspend(&host->class_dev);
 423 
 424         if (mmc_gpio_alloc(host)) {
 425                 put_device(&host->class_dev);
 426                 return NULL;
 427         }
 428 
 429         spin_lock_init(&host->lock);
 430         init_waitqueue_head(&host->wq);
 431         INIT_DELAYED_WORK(&host->detect, mmc_rescan);
 432         INIT_DELAYED_WORK(&host->sdio_irq_work, sdio_irq_work);
 433         timer_setup(&host->retune_timer, mmc_retune_timer, 0);
 434 
 435         /*
 436          * By default, hosts do not support SGIO or large requests.
 437          * They have to set these according to their abilities.
 438          */
 439         host->max_segs = 1;
 440         host->max_seg_size = PAGE_SIZE;
 441 
 442         host->max_req_size = PAGE_SIZE;
 443         host->max_blk_size = 512;
 444         host->max_blk_count = PAGE_SIZE / 512;
 445 
 446         host->fixed_drv_type = -EINVAL;
 447         host->ios.power_delay_ms = 10;
 448 
 449         return host;
 450 }
 451 
 452 EXPORT_SYMBOL(mmc_alloc_host);
 453 
 454 /**
 455  *      mmc_add_host - initialise host hardware
 456  *      @host: mmc host
 457  *
 458  *      Register the host with the driver model. The host must be
 459  *      prepared to start servicing requests before this function
 460  *      completes.
 461  */
 462 int mmc_add_host(struct mmc_host *host)
 463 {
 464         int err;
 465 
 466         WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) &&
 467                 !host->ops->enable_sdio_irq);
 468 
 469         err = device_add(&host->class_dev);
 470         if (err)
 471                 return err;
 472 
 473         led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
 474 
 475 #ifdef CONFIG_DEBUG_FS
 476         mmc_add_host_debugfs(host);
 477 #endif
 478 
 479         mmc_start_host(host);
 480         mmc_register_pm_notifier(host);
 481 
 482         return 0;
 483 }
 484 
 485 EXPORT_SYMBOL(mmc_add_host);
 486 
 487 /**
 488  *      mmc_remove_host - remove host hardware
 489  *      @host: mmc host
 490  *
 491  *      Unregister and remove all cards associated with this host,
 492  *      and power down the MMC bus. No new requests will be issued
 493  *      after this function has returned.
 494  */
 495 void mmc_remove_host(struct mmc_host *host)
 496 {
 497         mmc_unregister_pm_notifier(host);
 498         mmc_stop_host(host);
 499 
 500 #ifdef CONFIG_DEBUG_FS
 501         mmc_remove_host_debugfs(host);
 502 #endif
 503 
 504         device_del(&host->class_dev);
 505 
 506         led_trigger_unregister_simple(host->led);
 507 }
 508 
 509 EXPORT_SYMBOL(mmc_remove_host);
 510 
 511 /**
 512  *      mmc_free_host - free the host structure
 513  *      @host: mmc host
 514  *
 515  *      Free the host once all references to it have been dropped.
 516  */
 517 void mmc_free_host(struct mmc_host *host)
 518 {
 519         mmc_pwrseq_free(host);
 520         put_device(&host->class_dev);
 521 }
 522 
 523 EXPORT_SYMBOL(mmc_free_host);