api/api_storage.c

   1 /*
   2  * (C) Copyright 2007-2008 Semihalf
   3  *
   4  * Written by: Rafal Jaworowski <raj@semihalf.com>
   5  *
   6  * See file CREDITS for list of people who contributed to this
   7  * project.
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 2 of
  12  * the License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  22  * MA 02111-1307 USA
  23  *
  24  */
  25
  26 #include <config.h>
  27
  28 #if defined(CONFIG_API)
  29
  30 #include <common.h>
  31 #include <api_public.h>
  32
  33 #define DEBUG
  34 #undef DEBUG
  35
  36 #ifdef DEBUG
  37 #define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt, ##args); } while (0)
  38 #else
  39 #define debugf(fmt, args...)
  40 #endif
  41
  42 #define errf(fmt, args...) do { printf("ERROR @ %s(): ", __func__); printf(fmt, ##args); } while (0)
  43
  44
  45 #define ENUM_IDE        0
  46 #define ENUM_USB        1
  47 #define ENUM_SCSI       2
  48 #define ENUM_MMC        3
  49 #define ENUM_SATA       4
  50 #define ENUM_MAX        5
  51
  52 struct stor_spec {
  53         int             max_dev;
  54         int             enum_started;
  55         int             enum_ended;
  56         int             type;           /* "external" type: DT_STOR_{IDE,USB,etc} */
  57         char            *name;
  58 };
  59
  60 static struct stor_spec specs[ENUM_MAX] = { { 0, 0, 0, 0, "" }, };
  61
  62
  63 void dev_stor_init(void)
  64 {
  65 #if defined(CONFIG_CMD_IDE)
  66         specs[ENUM_IDE].max_dev = CFG_IDE_MAXDEVICE;
  67         specs[ENUM_IDE].enum_started = 0;
  68         specs[ENUM_IDE].enum_ended = 0;
  69         specs[ENUM_IDE].type = DEV_TYP_STOR | DT_STOR_IDE;
  70         specs[ENUM_IDE].name = "ide";
  71 #endif
  72 #if defined(CONFIG_CMD_MMC)
  73         specs[ENUM_MMC].max_dev = CFG_MMC_MAX_DEVICE;
  74         specs[ENUM_MMC].enum_started = 0;
  75         specs[ENUM_MMC].enum_ended = 0;
  76         specs[ENUM_MMC].type = DEV_TYP_STOR | DT_STOR_MMC;
  77         specs[ENUM_MMC].name = "mmc";
  78 #endif
  79 #if defined(CONFIG_CMD_SATA)
  80         specs[ENUM_SATA].max_dev = CFG_SATA_MAX_DEVICE;
  81         specs[ENUM_SATA].enum_started = 0;
  82         specs[ENUM_SATA].enum_ended = 0;
  83         specs[ENUM_SATA].type = DEV_TYP_STOR | DT_STOR_SATA;
  84         specs[ENUM_SATA].name = "sata";
  85 #endif
  86 #if defined(CONFIG_CMD_SCSI)
  87         specs[ENUM_SCSI].max_dev = CFG_SCSI_MAX_DEVICE;
  88         specs[ENUM_SCSI].enum_started = 0;
  89         specs[ENUM_SCSI].enum_ended = 0;
  90         specs[ENUM_SCSI].type = DEV_TYP_STOR | DT_STOR_SCSI;
  91         specs[ENUM_SCSI].name = "scsi";
  92 #endif
  93 #if defined(CONFIG_CMD_USB) && defined(CONFIG_USB_STORAGE)
  94         specs[ENUM_USB].max_dev = USB_MAX_STOR_DEV;
  95         specs[ENUM_USB].enum_started = 0;
  96         specs[ENUM_USB].enum_ended = 0;
  97         specs[ENUM_USB].type = DEV_TYP_STOR | DT_STOR_USB;
  98         specs[ENUM_USB].name = "usb";
  99 #endif
 100 }
 101
 102 /*
 103  * Finds next available device in the storage group
 104  *
 105  * type:        storage group type - ENUM_IDE, ENUM_SCSI etc.
 106  *
 107  * first:       if 1 the first device in the storage group is returned (if
 108  *              exists), if 0 the next available device is searched
 109  *
 110  * more:        returns 0/1 depending if there are more devices in this group
 111  *              available (for future iterations)
 112  *
 113  * returns:     0/1 depending if device found in this iteration
 114  */
 115 static int dev_stor_get(int type, int first, int *more, struct device_info *di)
 116 {
 117         int found = 0;
 118         *more = 0;
 119
 120         int i;
 121
 122         block_dev_desc_t *dd;
 123
 124         if (first) {
 125                 di->cookie = (void *)get_dev(specs[type].name, 0);
 126                 if (di->cookie == NULL)
 127                         return 0;
 128                 else
 129                         found = 1;
 130
 131         } else {
 132                 for (i = 0; i < specs[type].max_dev; i++)
 133                         if (di->cookie == (void *)get_dev(specs[type].name, i)) {
 134                                 /* previous cookie found -- advance to the
 135                                  * next device, if possible */
 136
 137                                 if (++i >= specs[type].max_dev) {
 138                                         /* out of range, no more to enum */
 139                                         di->cookie = NULL;
 140                                         break;
 141                                 }
 142
 143                                 di->cookie = (void *)get_dev(specs[type].name, i);
 144                                 if (di->cookie == NULL)
 145                                         return 0;
 146                                 else
 147                                         found = 1;
 148
 149                                 /* provide hint if there are more devices in
 150                                  * this group to enumerate */
 151                                 if ((i + 1) < specs[type].max_dev)
 152                                         *more = 1;
 153
 154                                 break;
 155                         }
 156         }
 157
 158         if (found) {
 159                 di->type = specs[type].type;
 160
 161                 if (di->cookie != NULL) {
 162                         dd = (block_dev_desc_t *)di->cookie;
 163                         if (dd->type == DEV_TYPE_UNKNOWN) {
 164                                 debugf("device instance exists, but is not active..");
 165                                 found = 0;
 166                         } else {
 167                                 di->di_stor.block_count = dd->lba;
 168                                 di->di_stor.block_size = dd->blksz;
 169                         }
 170                 }
 171
 172         } else
 173                 di->cookie = NULL;
 174
 175         return found;
 176 }
 177
 178
 179 /*
 180  * returns:     ENUM_IDE, ENUM_USB etc. based on block_dev_desc_t
 181  */
 182 static int dev_stor_type(block_dev_desc_t *dd)
 183 {
 184         int i, j;
 185
 186         for (i = ENUM_IDE; i < ENUM_MAX; i++)
 187                 for (j = 0; j < specs[i].max_dev; j++)
 188                         if (dd == get_dev(specs[i].name, j))
 189                                 return i;
 190
 191         return ENUM_MAX;
 192 }
 193
 194
 195 /*
 196  * returns:     0/1 whether cookie points to some device in this group
 197  */
 198 static int dev_is_stor(int type, struct device_info *di)
 199 {
 200         return (dev_stor_type(di->cookie) == type) ? 1 : 0;
 201 }
 202
 203
 204 static int dev_enum_stor(int type, struct device_info *di)
 205 {
 206         int found = 0, more = 0;
 207
 208         debugf("called, type %d\n", type);
 209
 210         /*
 211          * Formulae for enumerating storage devices:
 212          * 1. if cookie (hint from previous enum call) is NULL we start again
 213          *    with enumeration, so return the first available device, done.
 214          *
 215          * 2. if cookie is not NULL, check if it identifies some device in
 216          *    this group:
 217          *
 218          * 2a. if cookie is a storage device from our group (IDE, USB etc.),
 219          *     return next available (if exists) in this group
 220          *
 221          * 2b. if it isn't device from our group, check if such devices were
 222          *     ever enumerated before:
 223          *     - if not, return the first available device from this group
 224          *     - else return 0
 225          */
 226
 227         if (di->cookie == NULL) {
 228
 229                 debugf("group%d - enum restart\n", type);
 230
 231                 /*
 232                  * 1. Enumeration (re-)started: take the first available
 233                  * device, if exists
 234                  */
 235                 found = dev_stor_get(type, 1, &more, di);
 236                 specs[type].enum_started = 1;
 237
 238         } else if (dev_is_stor(type, di)) {
 239
 240                 debugf("group%d - enum continued for the next device\n", type);
 241
 242                 if (specs[type].enum_ended) {
 243                         debugf("group%d - nothing more to enum!\n", type);
 244                         return 0;
 245                 }
 246
 247                 /* 2a. Attempt to take a next available device in the group */
 248                 found = dev_stor_get(type, 0, &more, di);
 249
 250         } else {
 251
 252                 if (specs[type].enum_ended) {
 253                         debugf("group %d - already enumerated, skipping\n", type);
 254                         return 0;
 255                 }
 256
 257                 debugf("group%d - first time enum\n", type);
 258
 259                 if (specs[type].enum_started == 0) {
 260                         /*
 261                          * 2b.  If enumerating devices in this group did not
 262                          * happen before, it means the cookie pointed to a
 263                          * device frome some other group (another storage
 264                          * group, or network); in this case try to take the
 265                          * first available device from our group
 266                          */
 267                         specs[type].enum_started = 1;
 268
 269                         /*
 270                          * Attempt to take the first device in this group:
 271                          *'first element' flag is set
 272                          */
 273                         found = dev_stor_get(type, 1, &more, di);
 274
 275                 } else {
 276                         errf("group%d - out of order iteration\n", type);
 277                         found = 0;
 278                         more = 0;
 279                 }
 280         }
 281
 282         /*
 283          * If there are no more devices in this group, consider its
 284          * enumeration finished
 285          */
 286         specs[type].enum_ended = (!more) ? 1 : 0;
 287
 288         if (found)
 289                 debugf("device found, returning cookie 0x%08x\n",
 290                         (u_int32_t)di->cookie);
 291         else
 292                 debugf("no device found\n");
 293
 294         return found;
 295 }
 296
 297 void dev_enum_reset(void)
 298 {
 299         int i;
 300
 301         for (i = 0; i < ENUM_MAX; i ++) {
 302                 specs[i].enum_started = 0;
 303                 specs[i].enum_ended = 0;
 304         }
 305 }
 306
 307 int dev_enum_storage(struct device_info *di)
 308 {
 309         int i;
 310
 311         /*
 312          * check: ide, usb, scsi, mmc
 313          */
 314         for (i = ENUM_IDE; i < ENUM_MAX; i ++) {
 315                 if (dev_enum_stor(i, di))
 316                         return 1;
 317         }
 318
 319         return 0;
 320 }
 321
 322 static int dev_stor_is_valid(int type, block_dev_desc_t *dd)
 323 {
 324         int i;
 325
 326         for (i = 0; i < specs[type].max_dev; i++)
 327                 if (dd == get_dev(specs[type].name, i))
 328                         if (dd->type != DEV_TYPE_UNKNOWN)
 329                                 return 1;
 330
 331         return 0;
 332 }
 333
 334
 335 int dev_open_stor(void *cookie)
 336 {
 337         int type = dev_stor_type(cookie);
 338
 339         if (type == ENUM_MAX)
 340                 return API_ENODEV;
 341
 342         if (dev_stor_is_valid(type, (block_dev_desc_t *)cookie))
 343                 return 0;
 344
 345         return API_ENODEV;
 346 }
 347
 348
 349 int dev_close_stor(void *cookie)
 350 {
 351         /*
 352          * Not much to do as we actually do not alter storage devices upon
 353          * close
 354          */
 355         return 0;
 356 }
 357
 358
 359 static int dev_stor_index(block_dev_desc_t *dd)
 360 {
 361         int i, type;
 362
 363         type = dev_stor_type(dd);
 364         for (i = 0; i < specs[type].max_dev; i++)
 365                 if (dd == get_dev(specs[type].name, i))
 366                         return i;
 367
 368         return (specs[type].max_dev);
 369 }
 370
 371
 372 lbasize_t dev_read_stor(void *cookie, void *buf, lbasize_t len, lbastart_t start)
 373 {
 374         int type;
 375         block_dev_desc_t *dd = (block_dev_desc_t *)cookie;
 376
 377         if ((type = dev_stor_type(dd)) == ENUM_MAX)
 378                 return 0;
 379
 380         if (!dev_stor_is_valid(type, dd))
 381                 return 0;
 382
 383         if ((dd->block_read) == NULL) {
 384                 debugf("no block_read() for device 0x%08x\n", cookie);
 385                 return 0;
 386         }
 387
 388         return (dd->block_read(dev_stor_index(dd), start, len, buf));
 389 }
 390
 391 #endif /* CONFIG_API */