err.no Git - linux-2.6/blob - drivers/char/ipmi/ipmi_smic_sm.c

   1 /*
   2  * ipmi_smic_sm.c
   3  *
   4  * The state-machine driver for an IPMI SMIC driver
   5  *
   6  * It started as a copy of Corey Minyard's driver for the KSC interface
   7  * and the kernel patch "mmcdev-patch-245" by HP
   8  *
   9  * modified by: Hannes Schulz <schulz@schwaar.com>
  10  *              ipmi@schwaar.com
  11  *
  12  *
  13  * Corey Minyard's driver for the KSC interface has the following
  14  * copyright notice:
  15  *   Copyright 2002 MontaVista Software Inc.
  16  *
  17  * the kernel patch "mmcdev-patch-245" by HP has the following
  18  * copyright notice:
  19  * (c) Copyright 2001 Grant Grundler (c) Copyright
  20  * 2001 Hewlett-Packard Company
  21  *
  22  *
  23  *  This program is free software; you can redistribute it and/or modify it
  24  *  under the terms of the GNU General Public License as published by the
  25  *  Free Software Foundation; either version 2 of the License, or (at your
  26  *  option) any later version.
  27  *
  28  *
  29  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  30  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  31  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  32  *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  33  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  34  *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
  35  *  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  36  *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
  37  *  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
  38  *  USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  39  *
  40  *  You should have received a copy of the GNU General Public License along
  41  *  with this program; if not, write to the Free Software Foundation, Inc.,
  42  *  675 Mass Ave, Cambridge, MA 02139, USA.  */
  43
  44 #include <linux/kernel.h> /* For printk. */
  45 #include <linux/string.h>
  46 #include <linux/module.h>
  47 #include <linux/moduleparam.h>
  48 #include <linux/ipmi_msgdefs.h>         /* for completion codes */
  49 #include "ipmi_si_sm.h"
  50
  51 /* smic_debug is a bit-field
  52  *      SMIC_DEBUG_ENABLE -     turned on for now
  53  *      SMIC_DEBUG_MSG -        commands and their responses
  54  *      SMIC_DEBUG_STATES -     state machine
  55 */
  56 #define SMIC_DEBUG_STATES       4
  57 #define SMIC_DEBUG_MSG          2
  58 #define SMIC_DEBUG_ENABLE       1
  59
  60 static int smic_debug = 1;
  61 module_param(smic_debug, int, 0644);
  62 MODULE_PARM_DESC(smic_debug, "debug bitmask, 1=enable, 2=messages, 4=states");
  63
  64 enum smic_states {
  65         SMIC_IDLE,
  66         SMIC_START_OP,
  67         SMIC_OP_OK,
  68         SMIC_WRITE_START,
  69         SMIC_WRITE_NEXT,
  70         SMIC_WRITE_END,
  71         SMIC_WRITE2READ,
  72         SMIC_READ_START,
  73         SMIC_READ_NEXT,
  74         SMIC_READ_END,
  75         SMIC_HOSED
  76 };
  77
  78 #define MAX_SMIC_READ_SIZE 80
  79 #define MAX_SMIC_WRITE_SIZE 80
  80 #define SMIC_MAX_ERROR_RETRIES 3
  81
  82 /* Timeouts in microseconds. */
  83 #define SMIC_RETRY_TIMEOUT 2000000
  84
  85 /* SMIC Flags Register Bits */
  86 #define SMIC_RX_DATA_READY      0x80
  87 #define SMIC_TX_DATA_READY      0x40
  88 /*
  89  * SMIC_SMI and SMIC_EVM_DATA_AVAIL are only used by
  90  * a few systems, and then only by Systems Management
  91  * Interrupts, not by the OS.  Always ignore these bits.
  92  *
  93  */
  94 #define SMIC_SMI                0x10
  95 #define SMIC_EVM_DATA_AVAIL     0x08
  96 #define SMIC_SMS_DATA_AVAIL     0x04
  97 #define SMIC_FLAG_BSY           0x01
  98
  99 /* SMIC Error Codes */
 100 #define EC_NO_ERROR             0x00
 101 #define EC_ABORTED              0x01
 102 #define EC_ILLEGAL_CONTROL      0x02
 103 #define EC_NO_RESPONSE          0x03
 104 #define EC_ILLEGAL_COMMAND      0x04
 105 #define EC_BUFFER_FULL          0x05
 106
 107 struct si_sm_data
 108 {
 109         enum smic_states state;
 110         struct si_sm_io *io;
 111         unsigned char    write_data[MAX_SMIC_WRITE_SIZE];
 112         int              write_pos;
 113         int              write_count;
 114         int              orig_write_count;
 115         unsigned char    read_data[MAX_SMIC_READ_SIZE];
 116         int              read_pos;
 117         int              truncated;
 118         unsigned int     error_retries;
 119         long             smic_timeout;
 120 };
 121
 122 static unsigned int init_smic_data (struct si_sm_data *smic,
 123                                     struct si_sm_io *io)
 124 {
 125         smic->state = SMIC_IDLE;
 126         smic->io = io;
 127         smic->write_pos = 0;
 128         smic->write_count = 0;
 129         smic->orig_write_count = 0;
 130         smic->read_pos = 0;
 131         smic->error_retries = 0;
 132         smic->truncated = 0;
 133         smic->smic_timeout = SMIC_RETRY_TIMEOUT;
 134
 135         /* We use 3 bytes of I/O. */
 136         return 3;
 137 }
 138
 139 static int start_smic_transaction(struct si_sm_data *smic,
 140                                   unsigned char *data, unsigned int size)
 141 {
 142         unsigned int i;
 143
 144         if ((size < 2) || (size > MAX_SMIC_WRITE_SIZE)) {
 145                 return -1;
 146         }
 147         if ((smic->state != SMIC_IDLE) && (smic->state != SMIC_HOSED)) {
 148                 return -2;
 149         }
 150         if (smic_debug & SMIC_DEBUG_MSG) {
 151                 printk(KERN_INFO "start_smic_transaction -");
 152                 for (i = 0; i < size; i ++) {
 153                         printk (" %02x", (unsigned char) (data [i]));
 154                 }
 155                 printk ("\n");
 156         }
 157         smic->error_retries = 0;
 158         memcpy(smic->write_data, data, size);
 159         smic->write_count = size;
 160         smic->orig_write_count = size;
 161         smic->write_pos = 0;
 162         smic->read_pos = 0;
 163         smic->state = SMIC_START_OP;
 164         smic->smic_timeout = SMIC_RETRY_TIMEOUT;
 165         return 0;
 166 }
 167
 168 static int smic_get_result(struct si_sm_data *smic,
 169                            unsigned char *data, unsigned int length)
 170 {
 171         int i;
 172
 173         if (smic_debug & SMIC_DEBUG_MSG) {
 174                 printk (KERN_INFO "smic_get result -");
 175                 for (i = 0; i < smic->read_pos; i ++) {
 176                         printk (" %02x", (smic->read_data [i]));
 177                 }
 178                 printk ("\n");
 179         }
 180         if (length < smic->read_pos) {
 181                 smic->read_pos = length;
 182                 smic->truncated = 1;
 183         }
 184         memcpy(data, smic->read_data, smic->read_pos);
 185
 186         if ((length >= 3) && (smic->read_pos < 3)) {
 187                 data[2] = IPMI_ERR_UNSPECIFIED;
 188                 smic->read_pos = 3;
 189         }
 190         if (smic->truncated) {
 191                 data[2] = IPMI_ERR_MSG_TRUNCATED;
 192                 smic->truncated = 0;
 193         }
 194         return smic->read_pos;
 195 }
 196
 197 static inline unsigned char read_smic_flags(struct si_sm_data *smic)
 198 {
 199         return smic->io->inputb(smic->io, 2);
 200 }
 201
 202 static inline unsigned char read_smic_status(struct si_sm_data *smic)
 203 {
 204         return smic->io->inputb(smic->io, 1);
 205 }
 206
 207 static inline unsigned char read_smic_data(struct si_sm_data *smic)
 208 {
 209         return smic->io->inputb(smic->io, 0);
 210 }
 211
 212 static inline void write_smic_flags(struct si_sm_data *smic,
 213                                     unsigned char   flags)
 214 {
 215         smic->io->outputb(smic->io, 2, flags);
 216 }
 217
 218 static inline void write_smic_control(struct si_sm_data *smic,
 219                                       unsigned char   control)
 220 {
 221         smic->io->outputb(smic->io, 1, control);
 222 }
 223
 224 static inline void write_si_sm_data (struct si_sm_data *smic,
 225                                    unsigned char   data)
 226 {
 227         smic->io->outputb(smic->io, 0, data);
 228 }
 229
 230 static inline void start_error_recovery(struct si_sm_data *smic, char *reason)
 231 {
 232         (smic->error_retries)++;
 233         if (smic->error_retries > SMIC_MAX_ERROR_RETRIES) {
 234                 if (smic_debug & SMIC_DEBUG_ENABLE) {
 235                         printk(KERN_WARNING
 236                                "ipmi_smic_drv: smic hosed: %s\n", reason);
 237                 }
 238                 smic->state = SMIC_HOSED;
 239         } else {
 240                 smic->write_count = smic->orig_write_count;
 241                 smic->write_pos = 0;
 242                 smic->read_pos = 0;
 243                 smic->state = SMIC_START_OP;
 244                 smic->smic_timeout = SMIC_RETRY_TIMEOUT;
 245         }
 246 }
 247
 248 static inline void write_next_byte(struct si_sm_data *smic)
 249 {
 250         write_si_sm_data(smic, smic->write_data[smic->write_pos]);
 251         (smic->write_pos)++;
 252         (smic->write_count)--;
 253 }
 254
 255 static inline void read_next_byte (struct si_sm_data *smic)
 256 {
 257         if (smic->read_pos >= MAX_SMIC_READ_SIZE) {
 258                 read_smic_data (smic);
 259                 smic->truncated = 1;
 260         } else {
 261                 smic->read_data[smic->read_pos] = read_smic_data(smic);
 262                 (smic->read_pos)++;
 263         }
 264 }
 265
 266 /*  SMIC Control/Status Code Components */
 267 #define SMIC_GET_STATUS         0x00    /* Control form's name */
 268 #define SMIC_READY              0x00    /* Status  form's name */
 269 #define SMIC_WR_START           0x01    /* Unified Control/Status names... */
 270 #define SMIC_WR_NEXT            0x02
 271 #define SMIC_WR_END             0x03
 272 #define SMIC_RD_START           0x04
 273 #define SMIC_RD_NEXT            0x05
 274 #define SMIC_RD_END             0x06
 275 #define SMIC_CODE_MASK          0x0f
 276
 277 #define SMIC_CONTROL            0x00
 278 #define SMIC_STATUS             0x80
 279 #define SMIC_CS_MASK            0x80
 280
 281 #define SMIC_SMS                0x40
 282 #define SMIC_SMM                0x60
 283 #define SMIC_STREAM_MASK        0x60
 284
 285 /*  SMIC Control Codes */
 286 #define SMIC_CC_SMS_GET_STATUS  (SMIC_CONTROL|SMIC_SMS|SMIC_GET_STATUS)
 287 #define SMIC_CC_SMS_WR_START    (SMIC_CONTROL|SMIC_SMS|SMIC_WR_START)
 288 #define SMIC_CC_SMS_WR_NEXT     (SMIC_CONTROL|SMIC_SMS|SMIC_WR_NEXT)
 289 #define SMIC_CC_SMS_WR_END      (SMIC_CONTROL|SMIC_SMS|SMIC_WR_END)
 290 #define SMIC_CC_SMS_RD_START    (SMIC_CONTROL|SMIC_SMS|SMIC_RD_START)
 291 #define SMIC_CC_SMS_RD_NEXT     (SMIC_CONTROL|SMIC_SMS|SMIC_RD_NEXT)
 292 #define SMIC_CC_SMS_RD_END      (SMIC_CONTROL|SMIC_SMS|SMIC_RD_END)
 293
 294 #define SMIC_CC_SMM_GET_STATUS  (SMIC_CONTROL|SMIC_SMM|SMIC_GET_STATUS)
 295 #define SMIC_CC_SMM_WR_START    (SMIC_CONTROL|SMIC_SMM|SMIC_WR_START)
 296 #define SMIC_CC_SMM_WR_NEXT     (SMIC_CONTROL|SMIC_SMM|SMIC_WR_NEXT)
 297 #define SMIC_CC_SMM_WR_END      (SMIC_CONTROL|SMIC_SMM|SMIC_WR_END)
 298 #define SMIC_CC_SMM_RD_START    (SMIC_CONTROL|SMIC_SMM|SMIC_RD_START)
 299 #define SMIC_CC_SMM_RD_NEXT     (SMIC_CONTROL|SMIC_SMM|SMIC_RD_NEXT)
 300 #define SMIC_CC_SMM_RD_END      (SMIC_CONTROL|SMIC_SMM|SMIC_RD_END)
 301
 302 /*  SMIC Status Codes */
 303 #define SMIC_SC_SMS_READY       (SMIC_STATUS|SMIC_SMS|SMIC_READY)
 304 #define SMIC_SC_SMS_WR_START    (SMIC_STATUS|SMIC_SMS|SMIC_WR_START)
 305 #define SMIC_SC_SMS_WR_NEXT     (SMIC_STATUS|SMIC_SMS|SMIC_WR_NEXT)
 306 #define SMIC_SC_SMS_WR_END      (SMIC_STATUS|SMIC_SMS|SMIC_WR_END)
 307 #define SMIC_SC_SMS_RD_START    (SMIC_STATUS|SMIC_SMS|SMIC_RD_START)
 308 #define SMIC_SC_SMS_RD_NEXT     (SMIC_STATUS|SMIC_SMS|SMIC_RD_NEXT)
 309 #define SMIC_SC_SMS_RD_END      (SMIC_STATUS|SMIC_SMS|SMIC_RD_END)
 310
 311 #define SMIC_SC_SMM_READY       (SMIC_STATUS|SMIC_SMM|SMIC_READY)
 312 #define SMIC_SC_SMM_WR_START    (SMIC_STATUS|SMIC_SMM|SMIC_WR_START)
 313 #define SMIC_SC_SMM_WR_NEXT     (SMIC_STATUS|SMIC_SMM|SMIC_WR_NEXT)
 314 #define SMIC_SC_SMM_WR_END      (SMIC_STATUS|SMIC_SMM|SMIC_WR_END)
 315 #define SMIC_SC_SMM_RD_START    (SMIC_STATUS|SMIC_SMM|SMIC_RD_START)
 316 #define SMIC_SC_SMM_RD_NEXT     (SMIC_STATUS|SMIC_SMM|SMIC_RD_NEXT)
 317 #define SMIC_SC_SMM_RD_END      (SMIC_STATUS|SMIC_SMM|SMIC_RD_END)
 318
 319 /* these are the control/status codes we actually use
 320         SMIC_CC_SMS_GET_STATUS  0x40
 321         SMIC_CC_SMS_WR_START    0x41
 322         SMIC_CC_SMS_WR_NEXT     0x42
 323         SMIC_CC_SMS_WR_END      0x43
 324         SMIC_CC_SMS_RD_START    0x44
 325         SMIC_CC_SMS_RD_NEXT     0x45
 326         SMIC_CC_SMS_RD_END      0x46
 327
 328         SMIC_SC_SMS_READY       0xC0
 329         SMIC_SC_SMS_WR_START    0xC1
 330         SMIC_SC_SMS_WR_NEXT     0xC2
 331         SMIC_SC_SMS_WR_END      0xC3
 332         SMIC_SC_SMS_RD_START    0xC4
 333         SMIC_SC_SMS_RD_NEXT     0xC5
 334         SMIC_SC_SMS_RD_END      0xC6
 335 */
 336
 337 static enum si_sm_result smic_event (struct si_sm_data *smic, long time)
 338 {
 339         unsigned char status;
 340         unsigned char flags;
 341         unsigned char data;
 342
 343         if (smic->state == SMIC_HOSED) {
 344                 init_smic_data(smic, smic->io);
 345                 return SI_SM_HOSED;
 346         }
 347         if (smic->state != SMIC_IDLE) {
 348                 if (smic_debug & SMIC_DEBUG_STATES) {
 349                         printk(KERN_INFO
 350                                "smic_event - smic->smic_timeout = %ld,"
 351                                " time = %ld\n",
 352                                smic->smic_timeout, time);
 353                 }
 354 /* FIXME: smic_event is sometimes called with time > SMIC_RETRY_TIMEOUT */
 355                 if (time < SMIC_RETRY_TIMEOUT) {
 356                         smic->smic_timeout -= time;
 357                         if (smic->smic_timeout < 0) {
 358                                 start_error_recovery(smic, "smic timed out.");
 359                                 return SI_SM_CALL_WITH_DELAY;
 360                         }
 361                 }
 362         }
 363         flags = read_smic_flags(smic);
 364         if (flags & SMIC_FLAG_BSY)
 365                 return SI_SM_CALL_WITH_DELAY;
 366
 367         status = read_smic_status (smic);
 368         if (smic_debug & SMIC_DEBUG_STATES)
 369                 printk(KERN_INFO
 370                        "smic_event - state = %d, flags = 0x%02x,"
 371                        " status = 0x%02x\n",
 372                        smic->state, flags, status);
 373
 374         switch (smic->state) {
 375         case SMIC_IDLE:
 376                 /* in IDLE we check for available messages */
 377                 if (flags & SMIC_SMS_DATA_AVAIL)
 378                 {
 379                         return SI_SM_ATTN;
 380                 }
 381                 return SI_SM_IDLE;
 382
 383         case SMIC_START_OP:
 384                 /* sanity check whether smic is really idle */
 385                 write_smic_control(smic, SMIC_CC_SMS_GET_STATUS);
 386                 write_smic_flags(smic, flags | SMIC_FLAG_BSY);
 387                 smic->state = SMIC_OP_OK;
 388                 break;
 389
 390         case SMIC_OP_OK:
 391                 if (status != SMIC_SC_SMS_READY) {
 392                                 /* this should not happen */
 393                         start_error_recovery(smic,
 394                                              "state = SMIC_OP_OK,"
 395                                              " status != SMIC_SC_SMS_READY");
 396                         return SI_SM_CALL_WITH_DELAY;
 397                 }
 398                 /* OK so far; smic is idle let us start ... */
 399                 write_smic_control(smic, SMIC_CC_SMS_WR_START);
 400                 write_next_byte(smic);
 401                 write_smic_flags(smic, flags | SMIC_FLAG_BSY);
 402                 smic->state = SMIC_WRITE_START;
 403                 break;
 404
 405         case SMIC_WRITE_START:
 406                 if (status != SMIC_SC_SMS_WR_START) {
 407                         start_error_recovery(smic,
 408                                              "state = SMIC_WRITE_START, "
 409                                              "status != SMIC_SC_SMS_WR_START");
 410                         return SI_SM_CALL_WITH_DELAY;
 411                 }
 412                 /* we must not issue WR_(NEXT|END) unless
 413                    TX_DATA_READY is set */
 414                 if (flags & SMIC_TX_DATA_READY) {
 415                         if (smic->write_count == 1) {
 416                                 /* last byte */
 417                                 write_smic_control(smic, SMIC_CC_SMS_WR_END);
 418                                 smic->state = SMIC_WRITE_END;
 419                         } else {
 420                                 write_smic_control(smic, SMIC_CC_SMS_WR_NEXT);
 421                                 smic->state = SMIC_WRITE_NEXT;
 422                         }
 423                         write_next_byte(smic);
 424                         write_smic_flags(smic, flags | SMIC_FLAG_BSY);
 425                 }
 426                 else {
 427                         return SI_SM_CALL_WITH_DELAY;
 428                 }
 429                 break;
 430
 431         case SMIC_WRITE_NEXT:
 432                 if (status != SMIC_SC_SMS_WR_NEXT) {
 433                         start_error_recovery(smic,
 434                                              "state = SMIC_WRITE_NEXT, "
 435                                              "status != SMIC_SC_SMS_WR_NEXT");
 436                         return SI_SM_CALL_WITH_DELAY;
 437                 }
 438                 /* this is the same code as in SMIC_WRITE_START */
 439                 if (flags & SMIC_TX_DATA_READY) {
 440                         if (smic->write_count == 1) {
 441                                 write_smic_control(smic, SMIC_CC_SMS_WR_END);
 442                                 smic->state = SMIC_WRITE_END;
 443                         }
 444                         else {
 445                                 write_smic_control(smic, SMIC_CC_SMS_WR_NEXT);
 446                                 smic->state = SMIC_WRITE_NEXT;
 447                         }
 448                         write_next_byte(smic);
 449                         write_smic_flags(smic, flags | SMIC_FLAG_BSY);
 450                 }
 451                 else {
 452                         return SI_SM_CALL_WITH_DELAY;
 453                 }
 454                 break;
 455
 456         case SMIC_WRITE_END:
 457                 if (status != SMIC_SC_SMS_WR_END) {
 458                         start_error_recovery (smic,
 459                                               "state = SMIC_WRITE_END, "
 460                                               "status != SMIC_SC_SMS_WR_END");
 461                         return SI_SM_CALL_WITH_DELAY;
 462                 }
 463                 /* data register holds an error code */
 464                 data = read_smic_data(smic);
 465                 if (data != 0) {
 466                         if (smic_debug & SMIC_DEBUG_ENABLE) {
 467                                 printk(KERN_INFO
 468                                        "SMIC_WRITE_END: data = %02x\n", data);
 469                         }
 470                         start_error_recovery(smic,
 471                                              "state = SMIC_WRITE_END, "
 472                                              "data != SUCCESS");
 473                         return SI_SM_CALL_WITH_DELAY;
 474                 } else {
 475                         smic->state = SMIC_WRITE2READ;
 476                 }
 477                 break;
 478
 479         case SMIC_WRITE2READ:
 480                 /* we must wait for RX_DATA_READY to be set before we
 481                    can continue */
 482                 if (flags & SMIC_RX_DATA_READY) {
 483                         write_smic_control(smic, SMIC_CC_SMS_RD_START);
 484                         write_smic_flags(smic, flags | SMIC_FLAG_BSY);
 485                         smic->state = SMIC_READ_START;
 486                 } else {
 487                         return SI_SM_CALL_WITH_DELAY;
 488                 }
 489                 break;
 490
 491         case SMIC_READ_START:
 492                 if (status != SMIC_SC_SMS_RD_START) {
 493                         start_error_recovery(smic,
 494                                              "state = SMIC_READ_START, "
 495                                              "status != SMIC_SC_SMS_RD_START");
 496                         return SI_SM_CALL_WITH_DELAY;
 497                 }
 498                 if (flags & SMIC_RX_DATA_READY) {
 499                         read_next_byte(smic);
 500                         write_smic_control(smic, SMIC_CC_SMS_RD_NEXT);
 501                         write_smic_flags(smic, flags | SMIC_FLAG_BSY);
 502                         smic->state = SMIC_READ_NEXT;
 503                 } else {
 504                         return SI_SM_CALL_WITH_DELAY;
 505                 }
 506                 break;
 507
 508         case SMIC_READ_NEXT:
 509                 switch (status) {
 510                 /* smic tells us that this is the last byte to be read
 511                    --> clean up */
 512                 case SMIC_SC_SMS_RD_END:
 513                         read_next_byte(smic);
 514                         write_smic_control(smic, SMIC_CC_SMS_RD_END);
 515                         write_smic_flags(smic, flags | SMIC_FLAG_BSY);
 516                         smic->state = SMIC_READ_END;
 517                         break;
 518                 case SMIC_SC_SMS_RD_NEXT:
 519                         if (flags & SMIC_RX_DATA_READY) {
 520                                 read_next_byte(smic);
 521                                 write_smic_control(smic, SMIC_CC_SMS_RD_NEXT);
 522                                 write_smic_flags(smic, flags | SMIC_FLAG_BSY);
 523                                 smic->state = SMIC_READ_NEXT;
 524                         } else {
 525                                 return SI_SM_CALL_WITH_DELAY;
 526                         }
 527                         break;
 528                 default:
 529                         start_error_recovery(
 530                                 smic,
 531                                 "state = SMIC_READ_NEXT, "
 532                                 "status != SMIC_SC_SMS_RD_(NEXT|END)");
 533                         return SI_SM_CALL_WITH_DELAY;
 534                 }
 535                 break;
 536
 537         case SMIC_READ_END:
 538                 if (status != SMIC_SC_SMS_READY) {
 539                         start_error_recovery(smic,
 540                                              "state = SMIC_READ_END, "
 541                                              "status != SMIC_SC_SMS_READY");
 542                         return SI_SM_CALL_WITH_DELAY;
 543                 }
 544                 data = read_smic_data(smic);
 545                 /* data register holds an error code */
 546                 if (data != 0) {
 547                         if (smic_debug & SMIC_DEBUG_ENABLE) {
 548                                 printk(KERN_INFO
 549                                        "SMIC_READ_END: data = %02x\n", data);
 550                         }
 551                         start_error_recovery(smic,
 552                                              "state = SMIC_READ_END, "
 553                                              "data != SUCCESS");
 554                         return SI_SM_CALL_WITH_DELAY;
 555                 } else {
 556                         smic->state = SMIC_IDLE;
 557                         return SI_SM_TRANSACTION_COMPLETE;
 558                 }
 559
 560         case SMIC_HOSED:
 561                 init_smic_data(smic, smic->io);
 562                 return SI_SM_HOSED;
 563
 564         default:
 565                 if (smic_debug & SMIC_DEBUG_ENABLE) {
 566                         printk(KERN_WARNING "smic->state = %d\n", smic->state);
 567                         start_error_recovery(smic, "state = UNKNOWN");
 568                         return SI_SM_CALL_WITH_DELAY;
 569                 }
 570         }
 571         smic->smic_timeout = SMIC_RETRY_TIMEOUT;
 572         return SI_SM_CALL_WITHOUT_DELAY;
 573 }
 574
 575 static int smic_detect(struct si_sm_data *smic)
 576 {
 577         /* It's impossible for the SMIC fnags register to be all 1's,
 578            (assuming a properly functioning, self-initialized BMC)
 579            but that's what you get from reading a bogus address, so we
 580            test that first. */
 581         if (read_smic_flags(smic) == 0xff)
 582                 return 1;
 583
 584         return 0;
 585 }
 586
 587 static void smic_cleanup(struct si_sm_data *kcs)
 588 {
 589 }
 590
 591 static int smic_size(void)
 592 {
 593         return sizeof(struct si_sm_data);
 594 }
 595
 596 struct si_sm_handlers smic_smi_handlers =
 597 {
 598         .init_data         = init_smic_data,
 599         .start_transaction = start_smic_transaction,
 600         .get_result        = smic_get_result,
 601         .event             = smic_event,
 602         .detect            = smic_detect,
 603         .cleanup           = smic_cleanup,
 604         .size              = smic_size,
 605 };