drivers/input/serio/hp_sdc.c

   1 /*
   2  * HP i8042-based System Device Controller driver.
   3  *
   4  * Copyright (c) 2001 Brian S. Julin
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions, and the following disclaimer,
  12  *    without modification.
  13  * 2. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * Alternatively, this software may be distributed under the terms of the
  17  * GNU General Public License ("GPL").
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  23  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  *
  29  * References:
  30  * System Device Controller Microprocessor Firmware Theory of Operation
  31  *      for Part Number 1820-4784 Revision B.  Dwg No. A-1820-4784-2
  32  * Helge Deller's original hilkbd.c port for PA-RISC.
  33  *
  34  *
  35  * Driver theory of operation:
  36  *
  37  * hp_sdc_put does all writing to the SDC.  ISR can run on a different
  38  * CPU than hp_sdc_put, but only one CPU runs hp_sdc_put at a time
  39  * (it cannot really benefit from SMP anyway.)  A tasket fit this perfectly.
  40  *
  41  * All data coming back from the SDC is sent via interrupt and can be read
  42  * fully in the ISR, so there are no latency/throughput problems there.
  43  * The problem is with output, due to the slow clock speed of the SDC
  44  * compared to the CPU.  This should not be too horrible most of the time,
  45  * but if used with HIL devices that support the multibyte transfer command,
  46  * keeping outbound throughput flowing at the 6500KBps that the HIL is
  47  * capable of is more than can be done at HZ=100.
  48  *
  49  * Busy polling for IBF clear wastes CPU cycles and bus cycles.  hp_sdc.ibf
  50  * is set to 0 when the IBF flag in the status register has cleared.  ISR
  51  * may do this, and may also access the parts of queued transactions related
  52  * to reading data back from the SDC, but otherwise will not touch the
  53  * hp_sdc state. Whenever a register is written hp_sdc.ibf is set to 1.
  54  *
  55  * The i8042 write index and the values in the 4-byte input buffer
  56  * starting at 0x70 are kept track of in hp_sdc.wi, and .r7[], respectively,
  57  * to minimize the amount of IO needed to the SDC.  However these values
  58  * do not need to be locked since they are only ever accessed by hp_sdc_put.
  59  *
  60  * A timer task schedules the tasklet once per second just to make
  61  * sure it doesn't freeze up and to allow for bad reads to time out.
  62  */
  63
  64 #include <linux/hp_sdc.h>
  65 #include <linux/sched.h>
  66 #include <linux/errno.h>
  67 #include <linux/init.h>
  68 #include <linux/module.h>
  69 #include <linux/ioport.h>
  70 #include <linux/time.h>
  71 #include <linux/slab.h>
  72 #include <linux/hil.h>
  73 #include <asm/io.h>
  74 #include <asm/system.h>
  75
  76 /* Machine-specific abstraction */
  77
  78 #if defined(__hppa__)
  79 # include <asm/parisc-device.h>
  80 # define sdc_readb(p)           gsc_readb(p)
  81 # define sdc_writeb(v,p)        gsc_writeb((v),(p))
  82 #elif defined(__mc68000__)
  83 # include <asm/uaccess.h>
  84 # define sdc_readb(p)           in_8(p)
  85 # define sdc_writeb(v,p)        out_8((p),(v))
  86 #else
  87 # error "HIL is not supported on this platform"
  88 #endif
  89
  90 #define PREFIX "HP SDC: "
  91
  92 MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
  93 MODULE_DESCRIPTION("HP i8042-based SDC Driver");
  94 MODULE_LICENSE("Dual BSD/GPL");
  95
  96 EXPORT_SYMBOL(hp_sdc_request_timer_irq);
  97 EXPORT_SYMBOL(hp_sdc_request_hil_irq);
  98 EXPORT_SYMBOL(hp_sdc_request_cooked_irq);
  99
 100 EXPORT_SYMBOL(hp_sdc_release_timer_irq);
 101 EXPORT_SYMBOL(hp_sdc_release_hil_irq);
 102 EXPORT_SYMBOL(hp_sdc_release_cooked_irq);
 103
 104 EXPORT_SYMBOL(hp_sdc_enqueue_transaction);
 105 EXPORT_SYMBOL(hp_sdc_dequeue_transaction);
 106
 107 static hp_i8042_sdc     hp_sdc; /* All driver state is kept in here. */
 108
 109 /*************** primitives for use in any context *********************/
 110 static inline uint8_t hp_sdc_status_in8 (void) {
 111         uint8_t status;
 112         unsigned long flags;
 113
 114         write_lock_irqsave(&hp_sdc.ibf_lock, flags);
 115         status = sdc_readb(hp_sdc.status_io);
 116         if (!(status & HP_SDC_STATUS_IBF)) hp_sdc.ibf = 0;
 117         write_unlock_irqrestore(&hp_sdc.ibf_lock, flags);
 118
 119         return status;
 120 }
 121
 122 static inline uint8_t hp_sdc_data_in8 (void) {
 123         return sdc_readb(hp_sdc.data_io);
 124 }
 125
 126 static inline void hp_sdc_status_out8 (uint8_t val) {
 127         unsigned long flags;
 128
 129         write_lock_irqsave(&hp_sdc.ibf_lock, flags);
 130         hp_sdc.ibf = 1;
 131         if ((val & 0xf0) == 0xe0) hp_sdc.wi = 0xff;
 132         sdc_writeb(val, hp_sdc.status_io);
 133         write_unlock_irqrestore(&hp_sdc.ibf_lock, flags);
 134 }
 135
 136 static inline void hp_sdc_data_out8 (uint8_t val) {
 137         unsigned long flags;
 138
 139         write_lock_irqsave(&hp_sdc.ibf_lock, flags);
 140         hp_sdc.ibf = 1;
 141         sdc_writeb(val, hp_sdc.data_io);
 142         write_unlock_irqrestore(&hp_sdc.ibf_lock, flags);
 143 }
 144
 145 /*      Care must be taken to only invoke hp_sdc_spin_ibf when
 146  *      absolutely needed, or in rarely invoked subroutines.
 147  *      Not only does it waste CPU cycles, it also wastes bus cycles.
 148  */
 149 static inline void hp_sdc_spin_ibf(void) {
 150         unsigned long flags;
 151         rwlock_t *lock;
 152
 153         lock = &hp_sdc.ibf_lock;
 154
 155         read_lock_irqsave(lock, flags);
 156         if (!hp_sdc.ibf) {
 157                 read_unlock_irqrestore(lock, flags);
 158                 return;
 159         }
 160         read_unlock(lock);
 161         write_lock(lock);
 162         while (sdc_readb(hp_sdc.status_io) & HP_SDC_STATUS_IBF) {};
 163         hp_sdc.ibf = 0;
 164         write_unlock_irqrestore(lock, flags);
 165 }
 166
 167
 168 /************************ Interrupt context functions ************************/
 169 static void hp_sdc_take (int irq, void *dev_id, uint8_t status, uint8_t data) {
 170         hp_sdc_transaction *curr;
 171
 172         read_lock(&hp_sdc.rtq_lock);
 173         if (hp_sdc.rcurr < 0) {
 174                 read_unlock(&hp_sdc.rtq_lock);
 175                 return;
 176         }
 177         curr = hp_sdc.tq[hp_sdc.rcurr];
 178         read_unlock(&hp_sdc.rtq_lock);
 179
 180         curr->seq[curr->idx++] = status;
 181         curr->seq[curr->idx++] = data;
 182         hp_sdc.rqty -= 2;
 183         do_gettimeofday(&hp_sdc.rtv);
 184
 185         if (hp_sdc.rqty <= 0) {
 186                 /* All data has been gathered. */
 187                 if(curr->seq[curr->actidx] & HP_SDC_ACT_SEMAPHORE) {
 188                         if (curr->act.semaphore) up(curr->act.semaphore);
 189                 }
 190                 if(curr->seq[curr->actidx] & HP_SDC_ACT_CALLBACK) {
 191                         if (curr->act.irqhook)
 192                                 curr->act.irqhook(irq, dev_id, status, data);
 193                 }
 194                 curr->actidx = curr->idx;
 195                 curr->idx++;
 196                 /* Return control of this transaction */
 197                 write_lock(&hp_sdc.rtq_lock);
 198                 hp_sdc.rcurr = -1;
 199                 hp_sdc.rqty = 0;
 200                 write_unlock(&hp_sdc.rtq_lock);
 201                 tasklet_schedule(&hp_sdc.task);
 202         }
 203 }
 204
 205 static irqreturn_t hp_sdc_isr(int irq, void *dev_id) {
 206         uint8_t status, data;
 207
 208         status = hp_sdc_status_in8();
 209         /* Read data unconditionally to advance i8042. */
 210         data =   hp_sdc_data_in8();
 211
 212         /* For now we are ignoring these until we get the SDC to behave. */
 213         if (((status & 0xf1) == 0x51) && data == 0x82) {
 214           return IRQ_HANDLED;
 215         }
 216
 217         switch(status & HP_SDC_STATUS_IRQMASK) {
 218               case 0: /* This case is not documented. */
 219                 break;
 220               case HP_SDC_STATUS_USERTIMER:
 221               case HP_SDC_STATUS_PERIODIC:
 222               case HP_SDC_STATUS_TIMER:
 223                 read_lock(&hp_sdc.hook_lock);
 224                 if (hp_sdc.timer != NULL)
 225                         hp_sdc.timer(irq, dev_id, status, data);
 226                 read_unlock(&hp_sdc.hook_lock);
 227                 break;
 228               case HP_SDC_STATUS_REG:
 229                 hp_sdc_take(irq, dev_id, status, data);
 230                 break;
 231               case HP_SDC_STATUS_HILCMD:
 232               case HP_SDC_STATUS_HILDATA:
 233                 read_lock(&hp_sdc.hook_lock);
 234                 if (hp_sdc.hil != NULL)
 235                         hp_sdc.hil(irq, dev_id, status, data);
 236                 read_unlock(&hp_sdc.hook_lock);
 237                 break;
 238               case HP_SDC_STATUS_PUP:
 239                 read_lock(&hp_sdc.hook_lock);
 240                 if (hp_sdc.pup != NULL)
 241                         hp_sdc.pup(irq, dev_id, status, data);
 242                 else printk(KERN_INFO PREFIX "HP SDC reports successful PUP.\n");
 243                 read_unlock(&hp_sdc.hook_lock);
 244                 break;
 245               default:
 246                 read_lock(&hp_sdc.hook_lock);
 247                 if (hp_sdc.cooked != NULL)
 248                         hp_sdc.cooked(irq, dev_id, status, data);
 249                 read_unlock(&hp_sdc.hook_lock);
 250                 break;
 251         }
 252         return IRQ_HANDLED;
 253 }
 254
 255
 256 static irqreturn_t hp_sdc_nmisr(int irq, void *dev_id) {
 257         int status;
 258
 259         status = hp_sdc_status_in8();
 260         printk(KERN_WARNING PREFIX "NMI !\n");
 261
 262 #if 0
 263         if (status & HP_SDC_NMISTATUS_FHS) {
 264                 read_lock(&hp_sdc.hook_lock);
 265                 if (hp_sdc.timer != NULL)
 266                         hp_sdc.timer(irq, dev_id, status, 0);
 267                 read_unlock(&hp_sdc.hook_lock);
 268         }
 269         else {
 270                 /* TODO: pass this on to the HIL handler, or do SAK here? */
 271                 printk(KERN_WARNING PREFIX "HIL NMI\n");
 272         }
 273 #endif
 274         return IRQ_HANDLED;
 275 }
 276
 277
 278 /***************** Kernel (tasklet) context functions ****************/
 279
 280 unsigned long hp_sdc_put(void);
 281
 282 static void hp_sdc_tasklet(unsigned long foo) {
 283
 284         write_lock_irq(&hp_sdc.rtq_lock);
 285         if (hp_sdc.rcurr >= 0) {
 286                 struct timeval tv;
 287                 do_gettimeofday(&tv);
 288                 if (tv.tv_sec > hp_sdc.rtv.tv_sec) tv.tv_usec += 1000000;
 289                 if (tv.tv_usec - hp_sdc.rtv.tv_usec > HP_SDC_MAX_REG_DELAY) {
 290                         hp_sdc_transaction *curr;
 291                         uint8_t tmp;
 292
 293                         curr = hp_sdc.tq[hp_sdc.rcurr];
 294                         /* If this turns out to be a normal failure mode
 295                          * we'll need to figure out a way to communicate
 296                          * it back to the application. and be less verbose.
 297                          */
 298                         printk(KERN_WARNING PREFIX "read timeout (%ius)!\n",
 299                                tv.tv_usec - hp_sdc.rtv.tv_usec);
 300                         curr->idx += hp_sdc.rqty;
 301                         hp_sdc.rqty = 0;
 302                         tmp = curr->seq[curr->actidx];
 303                         curr->seq[curr->actidx] |= HP_SDC_ACT_DEAD;
 304                         if(tmp & HP_SDC_ACT_SEMAPHORE) {
 305                                 if (curr->act.semaphore)
 306                                         up(curr->act.semaphore);
 307                         }
 308                         if(tmp & HP_SDC_ACT_CALLBACK) {
 309                                 /* Note this means that irqhooks may be called
 310                                  * in tasklet/bh context.
 311                                  */
 312                                 if (curr->act.irqhook)
 313                                         curr->act.irqhook(0, 0, 0, 0);
 314                         }
 315                         curr->actidx = curr->idx;
 316                         curr->idx++;
 317                         hp_sdc.rcurr = -1;
 318                 }
 319         }
 320         write_unlock_irq(&hp_sdc.rtq_lock);
 321         hp_sdc_put();
 322 }
 323
 324 unsigned long hp_sdc_put(void) {
 325         hp_sdc_transaction *curr;
 326         uint8_t act;
 327         int idx, curridx;
 328
 329         int limit = 0;
 330
 331         write_lock(&hp_sdc.lock);
 332
 333         /* If i8042 buffers are full, we cannot do anything that
 334            requires output, so we skip to the administrativa. */
 335         if (hp_sdc.ibf) {
 336                 hp_sdc_status_in8();
 337                 if (hp_sdc.ibf) goto finish;
 338         }
 339
 340  anew:
 341         /* See if we are in the middle of a sequence. */
 342         if (hp_sdc.wcurr < 0) hp_sdc.wcurr = 0;
 343         read_lock_irq(&hp_sdc.rtq_lock);
 344         if (hp_sdc.rcurr == hp_sdc.wcurr) hp_sdc.wcurr++;
 345         read_unlock_irq(&hp_sdc.rtq_lock);
 346         if (hp_sdc.wcurr >= HP_SDC_QUEUE_LEN) hp_sdc.wcurr = 0;
 347         curridx = hp_sdc.wcurr;
 348
 349         if (hp_sdc.tq[curridx] != NULL) goto start;
 350
 351         while (++curridx != hp_sdc.wcurr) {
 352                 if (curridx >= HP_SDC_QUEUE_LEN) {
 353                         curridx = -1; /* Wrap to top */
 354                         continue;
 355                 }
 356                 read_lock_irq(&hp_sdc.rtq_lock);
 357                 if (hp_sdc.rcurr == curridx) {
 358                         read_unlock_irq(&hp_sdc.rtq_lock);
 359                         continue;
 360                 }
 361                 read_unlock_irq(&hp_sdc.rtq_lock);
 362                 if (hp_sdc.tq[curridx] != NULL) break; /* Found one. */
 363         }
 364         if (curridx == hp_sdc.wcurr) { /* There's nothing queued to do. */
 365                 curridx = -1;
 366         }
 367         hp_sdc.wcurr = curridx;
 368
 369  start:
 370
 371         /* Check to see if the interrupt mask needs to be set. */
 372         if (hp_sdc.set_im) {
 373                 hp_sdc_status_out8(hp_sdc.im | HP_SDC_CMD_SET_IM);
 374                 hp_sdc.set_im = 0;
 375                 goto finish;
 376         }
 377
 378         if (hp_sdc.wcurr == -1) goto done;
 379
 380         curr = hp_sdc.tq[curridx];
 381         idx = curr->actidx;
 382
 383         if (curr->actidx >= curr->endidx) {
 384                 hp_sdc.tq[curridx] = NULL;
 385                 /* Interleave outbound data between the transactions. */
 386                 hp_sdc.wcurr++;
 387                 if (hp_sdc.wcurr >= HP_SDC_QUEUE_LEN) hp_sdc.wcurr = 0;
 388                 goto finish;
 389         }
 390
 391         act = curr->seq[idx];
 392         idx++;
 393
 394         if (curr->idx >= curr->endidx) {
 395                 if (act & HP_SDC_ACT_DEALLOC) kfree(curr);
 396                 hp_sdc.tq[curridx] = NULL;
 397                 /* Interleave outbound data between the transactions. */
 398                 hp_sdc.wcurr++;
 399                 if (hp_sdc.wcurr >= HP_SDC_QUEUE_LEN) hp_sdc.wcurr = 0;
 400                 goto finish;
 401         }
 402
 403         while (act & HP_SDC_ACT_PRECMD) {
 404                 if (curr->idx != idx) {
 405                         idx++;
 406                         act &= ~HP_SDC_ACT_PRECMD;
 407                         break;
 408                 }
 409                 hp_sdc_status_out8(curr->seq[idx]);
 410                 curr->idx++;
 411                 /* act finished? */
 412                 if ((act & HP_SDC_ACT_DURING) == HP_SDC_ACT_PRECMD)
 413                   goto actdone;
 414                 /* skip quantity field if data-out sequence follows. */
 415                 if (act & HP_SDC_ACT_DATAOUT) curr->idx++;
 416                 goto finish;
 417         }
 418         if (act & HP_SDC_ACT_DATAOUT) {
 419                 int qty;
 420
 421                 qty = curr->seq[idx];
 422                 idx++;
 423                 if (curr->idx - idx < qty) {
 424                         hp_sdc_data_out8(curr->seq[curr->idx]);
 425                         curr->idx++;
 426                         /* act finished? */
 427                         if ((curr->idx - idx >= qty) &&
 428                             ((act & HP_SDC_ACT_DURING) == HP_SDC_ACT_DATAOUT))
 429                                 goto actdone;
 430                         goto finish;
 431                 }
 432                 idx += qty;
 433                 act &= ~HP_SDC_ACT_DATAOUT;
 434         }
 435         else while (act & HP_SDC_ACT_DATAREG) {
 436                 int mask;
 437                 uint8_t w7[4];
 438
 439                 mask = curr->seq[idx];
 440                 if (idx != curr->idx) {
 441                         idx++;
 442                         idx += !!(mask & 1);
 443                         idx += !!(mask & 2);
 444                         idx += !!(mask & 4);
 445                         idx += !!(mask & 8);
 446                         act &= ~HP_SDC_ACT_DATAREG;
 447                         break;
 448                 }
 449
 450                 w7[0] = (mask & 1) ? curr->seq[++idx] : hp_sdc.r7[0];
 451                 w7[1] = (mask & 2) ? curr->seq[++idx] : hp_sdc.r7[1];
 452                 w7[2] = (mask & 4) ? curr->seq[++idx] : hp_sdc.r7[2];
 453                 w7[3] = (mask & 8) ? curr->seq[++idx] : hp_sdc.r7[3];
 454
 455                 if (hp_sdc.wi > 0x73 || hp_sdc.wi < 0x70 ||
 456                         w7[hp_sdc.wi-0x70] == hp_sdc.r7[hp_sdc.wi-0x70]) {
 457                         int i = 0;
 458
 459                         /* Need to point the write index register */
 460                         while ((i < 4) && w7[i] == hp_sdc.r7[i]) i++;
 461                         if (i < 4) {
 462                                 hp_sdc_status_out8(HP_SDC_CMD_SET_D0 + i);
 463                                 hp_sdc.wi = 0x70 + i;
 464                                 goto finish;
 465                         }
 466                         idx++;
 467                         if ((act & HP_SDC_ACT_DURING) == HP_SDC_ACT_DATAREG)
 468                                 goto actdone;
 469                         curr->idx = idx;
 470                         act &= ~HP_SDC_ACT_DATAREG;
 471                         break;
 472                 }
 473
 474                 hp_sdc_data_out8(w7[hp_sdc.wi - 0x70]);
 475                 hp_sdc.r7[hp_sdc.wi - 0x70] = w7[hp_sdc.wi - 0x70];
 476                 hp_sdc.wi++; /* write index register autoincrements */
 477                 {
 478                         int i = 0;
 479
 480                         while ((i < 4) && w7[i] == hp_sdc.r7[i]) i++;
 481                         if (i >= 4) {
 482                                 curr->idx = idx + 1;
 483                                 if ((act & HP_SDC_ACT_DURING) ==
 484                                     HP_SDC_ACT_DATAREG)
 485                                         goto actdone;
 486                         }
 487                 }
 488                 goto finish;
 489         }
 490         /* We don't go any further in the command if there is a pending read,
 491            because we don't want interleaved results. */
 492         read_lock_irq(&hp_sdc.rtq_lock);
 493         if (hp_sdc.rcurr >= 0) {
 494                 read_unlock_irq(&hp_sdc.rtq_lock);
 495                 goto finish;
 496         }
 497         read_unlock_irq(&hp_sdc.rtq_lock);
 498
 499
 500         if (act & HP_SDC_ACT_POSTCMD) {
 501                 uint8_t postcmd;
 502
 503                 /* curr->idx should == idx at this point. */
 504                 postcmd = curr->seq[idx];
 505                 curr->idx++;
 506                 if (act & HP_SDC_ACT_DATAIN) {
 507
 508                         /* Start a new read */
 509                         hp_sdc.rqty = curr->seq[curr->idx];
 510                         do_gettimeofday(&hp_sdc.rtv);
 511                         curr->idx++;
 512                         /* Still need to lock here in case of spurious irq. */
 513                         write_lock_irq(&hp_sdc.rtq_lock);
 514                         hp_sdc.rcurr = curridx;
 515                         write_unlock_irq(&hp_sdc.rtq_lock);
 516                         hp_sdc_status_out8(postcmd);
 517                         goto finish;
 518                 }
 519                 hp_sdc_status_out8(postcmd);
 520                 goto actdone;
 521         }
 522
 523 actdone:
 524         if (act & HP_SDC_ACT_SEMAPHORE) {
 525                 up(curr->act.semaphore);
 526         }
 527         else if (act & HP_SDC_ACT_CALLBACK) {
 528                 curr->act.irqhook(0,0,0,0);
 529         }
 530         if (curr->idx >= curr->endidx) { /* This transaction is over. */
 531                 if (act & HP_SDC_ACT_DEALLOC) kfree(curr);
 532                 hp_sdc.tq[curridx] = NULL;
 533         }
 534         else {
 535                 curr->actidx = idx + 1;
 536                 curr->idx = idx + 2;
 537         }
 538         /* Interleave outbound data between the transactions. */
 539         hp_sdc.wcurr++;
 540         if (hp_sdc.wcurr >= HP_SDC_QUEUE_LEN) hp_sdc.wcurr = 0;
 541
 542  finish:
 543         /* If by some quirk IBF has cleared and our ISR has run to
 544            see that that has happened, do it all again. */
 545         if (!hp_sdc.ibf && limit++ < 20) goto anew;
 546
 547  done:
 548         if (hp_sdc.wcurr >= 0) tasklet_schedule(&hp_sdc.task);
 549         write_unlock(&hp_sdc.lock);
 550         return 0;
 551 }
 552
 553 /******* Functions called in either user or kernel context ****/
 554 int hp_sdc_enqueue_transaction(hp_sdc_transaction *this) {
 555         unsigned long flags;
 556         int i;
 557
 558         if (this == NULL) {
 559                 tasklet_schedule(&hp_sdc.task);
 560                 return -EINVAL;
 561         };
 562
 563         write_lock_irqsave(&hp_sdc.lock, flags);
 564
 565         /* Can't have same transaction on queue twice */
 566         for (i=0; i < HP_SDC_QUEUE_LEN; i++)
 567                 if (hp_sdc.tq[i] == this) goto fail;
 568
 569         this->actidx = 0;
 570         this->idx = 1;
 571
 572         /* Search for empty slot */
 573         for (i=0; i < HP_SDC_QUEUE_LEN; i++) {
 574                 if (hp_sdc.tq[i] == NULL) {
 575                         hp_sdc.tq[i] = this;
 576                         write_unlock_irqrestore(&hp_sdc.lock, flags);
 577                         tasklet_schedule(&hp_sdc.task);
 578                         return 0;
 579                 }
 580         }
 581         write_unlock_irqrestore(&hp_sdc.lock, flags);
 582         printk(KERN_WARNING PREFIX "No free slot to add transaction.\n");
 583         return -EBUSY;
 584
 585  fail:
 586         write_unlock_irqrestore(&hp_sdc.lock,flags);
 587         printk(KERN_WARNING PREFIX "Transaction add failed: transaction already queued?\n");
 588         return -EINVAL;
 589 }
 590
 591 int hp_sdc_dequeue_transaction(hp_sdc_transaction *this) {
 592         unsigned long flags;
 593         int i;
 594
 595         write_lock_irqsave(&hp_sdc.lock, flags);
 596
 597         /* TODO: don't remove it if it's not done. */
 598
 599         for (i=0; i < HP_SDC_QUEUE_LEN; i++)
 600                 if (hp_sdc.tq[i] == this) hp_sdc.tq[i] = NULL;
 601
 602         write_unlock_irqrestore(&hp_sdc.lock, flags);
 603         return 0;
 604 }
 605
 606
 607
 608 /********************** User context functions **************************/
 609 int hp_sdc_request_timer_irq(hp_sdc_irqhook *callback) {
 610
 611         if (callback == NULL || hp_sdc.dev == NULL) {
 612                 return -EINVAL;
 613         }
 614         write_lock_irq(&hp_sdc.hook_lock);
 615         if (hp_sdc.timer != NULL) {
 616                 write_unlock_irq(&hp_sdc.hook_lock);
 617                 return -EBUSY;
 618         }
 619
 620         hp_sdc.timer = callback;
 621         /* Enable interrupts from the timers */
 622         hp_sdc.im &= ~HP_SDC_IM_FH;
 623         hp_sdc.im &= ~HP_SDC_IM_PT;
 624         hp_sdc.im &= ~HP_SDC_IM_TIMERS;
 625         hp_sdc.set_im = 1;
 626         write_unlock_irq(&hp_sdc.hook_lock);
 627
 628         tasklet_schedule(&hp_sdc.task);
 629
 630         return 0;
 631 }
 632
 633 int hp_sdc_request_hil_irq(hp_sdc_irqhook *callback) {
 634
 635         if (callback == NULL || hp_sdc.dev == NULL) {
 636                 return -EINVAL;
 637         }
 638         write_lock_irq(&hp_sdc.hook_lock);
 639         if (hp_sdc.hil != NULL) {
 640                 write_unlock_irq(&hp_sdc.hook_lock);
 641                 return -EBUSY;
 642         }
 643
 644         hp_sdc.hil = callback;
 645         hp_sdc.im &= ~(HP_SDC_IM_HIL | HP_SDC_IM_RESET);
 646         hp_sdc.set_im = 1;
 647         write_unlock_irq(&hp_sdc.hook_lock);
 648
 649         tasklet_schedule(&hp_sdc.task);
 650
 651         return 0;
 652 }
 653
 654 int hp_sdc_request_cooked_irq(hp_sdc_irqhook *callback) {
 655
 656         if (callback == NULL || hp_sdc.dev == NULL) {
 657                 return -EINVAL;
 658         }
 659         write_lock_irq(&hp_sdc.hook_lock);
 660         if (hp_sdc.cooked != NULL) {
 661                 write_unlock_irq(&hp_sdc.hook_lock);
 662                 return -EBUSY;
 663         }
 664
 665         /* Enable interrupts from the HIL MLC */
 666         hp_sdc.cooked = callback;
 667         hp_sdc.im &= ~(HP_SDC_IM_HIL | HP_SDC_IM_RESET);
 668         hp_sdc.set_im = 1;
 669         write_unlock_irq(&hp_sdc.hook_lock);
 670
 671         tasklet_schedule(&hp_sdc.task);
 672
 673         return 0;
 674 }
 675
 676 int hp_sdc_release_timer_irq(hp_sdc_irqhook *callback) {
 677
 678
 679         write_lock_irq(&hp_sdc.hook_lock);
 680         if ((callback != hp_sdc.timer) ||
 681             (hp_sdc.timer == NULL)) {
 682                 write_unlock_irq(&hp_sdc.hook_lock);
 683                 return -EINVAL;
 684         }
 685
 686         /* Disable interrupts from the timers */
 687         hp_sdc.timer = NULL;
 688         hp_sdc.im |= HP_SDC_IM_TIMERS;
 689         hp_sdc.im |= HP_SDC_IM_FH;
 690         hp_sdc.im |= HP_SDC_IM_PT;
 691         hp_sdc.set_im = 1;
 692         write_unlock_irq(&hp_sdc.hook_lock);
 693         tasklet_schedule(&hp_sdc.task);
 694
 695         return 0;
 696 }
 697
 698 int hp_sdc_release_hil_irq(hp_sdc_irqhook *callback) {
 699
 700         write_lock_irq(&hp_sdc.hook_lock);
 701         if ((callback != hp_sdc.hil) ||
 702             (hp_sdc.hil == NULL)) {
 703                 write_unlock_irq(&hp_sdc.hook_lock);
 704                 return -EINVAL;
 705         }
 706
 707         hp_sdc.hil = NULL;
 708         /* Disable interrupts from HIL only if there is no cooked driver. */
 709         if(hp_sdc.cooked == NULL) {
 710                 hp_sdc.im |= (HP_SDC_IM_HIL | HP_SDC_IM_RESET);
 711                 hp_sdc.set_im = 1;
 712         }
 713         write_unlock_irq(&hp_sdc.hook_lock);
 714         tasklet_schedule(&hp_sdc.task);
 715
 716         return 0;
 717 }
 718
 719 int hp_sdc_release_cooked_irq(hp_sdc_irqhook *callback) {
 720
 721         write_lock_irq(&hp_sdc.hook_lock);
 722         if ((callback != hp_sdc.cooked) ||
 723             (hp_sdc.cooked == NULL)) {
 724                 write_unlock_irq(&hp_sdc.hook_lock);
 725                 return -EINVAL;
 726         }
 727
 728         hp_sdc.cooked = NULL;
 729         /* Disable interrupts from HIL only if there is no raw HIL driver. */
 730         if(hp_sdc.hil == NULL) {
 731                 hp_sdc.im |= (HP_SDC_IM_HIL | HP_SDC_IM_RESET);
 732                 hp_sdc.set_im = 1;
 733         }
 734         write_unlock_irq(&hp_sdc.hook_lock);
 735         tasklet_schedule(&hp_sdc.task);
 736
 737         return 0;
 738 }
 739
 740 /************************* Keepalive timer task *********************/
 741
 742 void hp_sdc_kicker (unsigned long data) {
 743         tasklet_schedule(&hp_sdc.task);
 744         /* Re-insert the periodic task. */
 745         mod_timer(&hp_sdc.kicker, jiffies + HZ);
 746 }
 747
 748 /************************** Module Initialization ***************************/
 749
 750 #if defined(__hppa__)
 751
 752 static struct parisc_device_id hp_sdc_tbl[] = {
 753         {
 754                 .hw_type =      HPHW_FIO,
 755                 .hversion_rev = HVERSION_REV_ANY_ID,
 756                 .hversion =     HVERSION_ANY_ID,
 757                 .sversion =     0x73,
 758          },
 759         { 0, }
 760 };
 761
 762 MODULE_DEVICE_TABLE(parisc, hp_sdc_tbl);
 763
 764 static int __init hp_sdc_init_hppa(struct parisc_device *d);
 765
 766 static struct parisc_driver hp_sdc_driver = {
 767         .name =         "hp_sdc",
 768         .id_table =     hp_sdc_tbl,
 769         .probe =        hp_sdc_init_hppa,
 770 };
 771
 772 #endif /* __hppa__ */
 773
 774 static int __init hp_sdc_init(void)
 775 {
 776         int i;
 777         char *errstr;
 778         hp_sdc_transaction t_sync;
 779         uint8_t ts_sync[6];
 780         struct semaphore s_sync;
 781
 782         rwlock_init(&hp_sdc.lock);
 783         rwlock_init(&hp_sdc.ibf_lock);
 784         rwlock_init(&hp_sdc.rtq_lock);
 785         rwlock_init(&hp_sdc.hook_lock);
 786
 787         hp_sdc.timer            = NULL;
 788         hp_sdc.hil              = NULL;
 789         hp_sdc.pup              = NULL;
 790         hp_sdc.cooked           = NULL;
 791         hp_sdc.im               = HP_SDC_IM_MASK;  /* Mask maskable irqs */
 792         hp_sdc.set_im           = 1;
 793         hp_sdc.wi               = 0xff;
 794         hp_sdc.r7[0]            = 0xff;
 795         hp_sdc.r7[1]            = 0xff;
 796         hp_sdc.r7[2]            = 0xff;
 797         hp_sdc.r7[3]            = 0xff;
 798         hp_sdc.ibf              = 1;
 799
 800         for (i = 0; i < HP_SDC_QUEUE_LEN; i++) hp_sdc.tq[i] = NULL;
 801         hp_sdc.wcurr            = -1;
 802         hp_sdc.rcurr            = -1;
 803         hp_sdc.rqty             = 0;
 804
 805         hp_sdc.dev_err = -ENODEV;
 806
 807         errstr = "IO not found for";
 808         if (!hp_sdc.base_io) goto err0;
 809
 810         errstr = "IRQ not found for";
 811         if (!hp_sdc.irq) goto err0;
 812
 813         hp_sdc.dev_err = -EBUSY;
 814
 815 #if defined(__hppa__)
 816         errstr = "IO not available for";
 817         if (request_region(hp_sdc.data_io, 2, hp_sdc_driver.name)) goto err0;
 818 #endif
 819
 820         errstr = "IRQ not available for";
 821         if(request_irq(hp_sdc.irq, &hp_sdc_isr, 0, "HP SDC",
 822                        (void *) hp_sdc.base_io)) goto err1;
 823
 824         errstr = "NMI not available for";
 825         if (request_irq(hp_sdc.nmi, &hp_sdc_nmisr, 0, "HP SDC NMI",
 826                         (void *) hp_sdc.base_io)) goto err2;
 827
 828         printk(KERN_INFO PREFIX "HP SDC at 0x%p, IRQ %d (NMI IRQ %d)\n",
 829                (void *)hp_sdc.base_io, hp_sdc.irq, hp_sdc.nmi);
 830
 831         hp_sdc_status_in8();
 832         hp_sdc_data_in8();
 833
 834         tasklet_init(&hp_sdc.task, hp_sdc_tasklet, 0);
 835
 836         /* Sync the output buffer registers, thus scheduling hp_sdc_tasklet. */
 837         t_sync.actidx   = 0;
 838         t_sync.idx      = 1;
 839         t_sync.endidx   = 6;
 840         t_sync.seq      = ts_sync;
 841         ts_sync[0]      = HP_SDC_ACT_DATAREG | HP_SDC_ACT_SEMAPHORE;
 842         ts_sync[1]      = 0x0f;
 843         ts_sync[2] = ts_sync[3] = ts_sync[4] = ts_sync[5] = 0;
 844         t_sync.act.semaphore = &s_sync;
 845         init_MUTEX_LOCKED(&s_sync);
 846         hp_sdc_enqueue_transaction(&t_sync);
 847         down(&s_sync); /* Wait for t_sync to complete */
 848
 849         /* Create the keepalive task */
 850         init_timer(&hp_sdc.kicker);
 851         hp_sdc.kicker.expires = jiffies + HZ;
 852         hp_sdc.kicker.function = &hp_sdc_kicker;
 853         add_timer(&hp_sdc.kicker);
 854
 855         hp_sdc.dev_err = 0;
 856         return 0;
 857  err2:
 858         free_irq(hp_sdc.irq, NULL);
 859  err1:
 860         release_region(hp_sdc.data_io, 2);
 861  err0:
 862         printk(KERN_WARNING PREFIX ": %s SDC IO=0x%p IRQ=0x%x NMI=0x%x\n",
 863                 errstr, (void *)hp_sdc.base_io, hp_sdc.irq, hp_sdc.nmi);
 864         hp_sdc.dev = NULL;
 865         return hp_sdc.dev_err;
 866 }
 867
 868 #if defined(__hppa__)
 869
 870 static int __init hp_sdc_init_hppa(struct parisc_device *d)
 871 {
 872         if (!d) return 1;
 873         if (hp_sdc.dev != NULL) return 1;       /* We only expect one SDC */
 874
 875         hp_sdc.dev              = d;
 876         hp_sdc.irq              = d->irq;
 877         hp_sdc.nmi              = d->aux_irq;
 878         hp_sdc.base_io          = d->hpa.start;
 879         hp_sdc.data_io          = d->hpa.start + 0x800;
 880         hp_sdc.status_io        = d->hpa.start + 0x801;
 881
 882         return hp_sdc_init();
 883 }
 884
 885 #endif /* __hppa__ */
 886
 887 #if !defined(__mc68000__) /* Link error on m68k! */
 888 static void __exit hp_sdc_exit(void)
 889 #else
 890 static void hp_sdc_exit(void)
 891 #endif
 892 {
 893         write_lock_irq(&hp_sdc.lock);
 894
 895         /* Turn off all maskable "sub-function" irq's. */
 896         hp_sdc_spin_ibf();
 897         sdc_writeb(HP_SDC_CMD_SET_IM | HP_SDC_IM_MASK, hp_sdc.status_io);
 898
 899         /* Wait until we know this has been processed by the i8042 */
 900         hp_sdc_spin_ibf();
 901
 902         free_irq(hp_sdc.nmi, NULL);
 903         free_irq(hp_sdc.irq, NULL);
 904         write_unlock_irq(&hp_sdc.lock);
 905
 906         del_timer(&hp_sdc.kicker);
 907
 908         tasklet_kill(&hp_sdc.task);
 909
 910 /*        release_region(hp_sdc.data_io, 2); */
 911
 912 #if defined(__hppa__)
 913         if (unregister_parisc_driver(&hp_sdc_driver))
 914                 printk(KERN_WARNING PREFIX "Error unregistering HP SDC");
 915 #endif
 916 }
 917
 918 static int __init hp_sdc_register(void)
 919 {
 920         hp_sdc_transaction tq_init;
 921         uint8_t tq_init_seq[5];
 922         struct semaphore tq_init_sem;
 923 #if defined(__mc68000__)
 924         mm_segment_t fs;
 925         unsigned char i;
 926 #endif
 927
 928         hp_sdc.dev = NULL;
 929         hp_sdc.dev_err = 0;
 930 #if defined(__hppa__)
 931         if (register_parisc_driver(&hp_sdc_driver)) {
 932                 printk(KERN_WARNING PREFIX "Error registering SDC with system bus tree.\n");
 933                 return -ENODEV;
 934         }
 935 #elif defined(__mc68000__)
 936         if (!MACH_IS_HP300)
 937             return -ENODEV;
 938
 939         hp_sdc.irq       = 1;
 940         hp_sdc.nmi       = 7;
 941         hp_sdc.base_io   = (unsigned long) 0xf0428000;
 942         hp_sdc.data_io   = (unsigned long) hp_sdc.base_io + 1;
 943         hp_sdc.status_io = (unsigned long) hp_sdc.base_io + 3;
 944         fs = get_fs();
 945         set_fs(KERNEL_DS);
 946         if (!get_user(i, (unsigned char *)hp_sdc.data_io))
 947                 hp_sdc.dev = (void *)1;
 948         set_fs(fs);
 949         hp_sdc.dev_err   = hp_sdc_init();
 950 #endif
 951         if (hp_sdc.dev == NULL) {
 952                 printk(KERN_WARNING PREFIX "No SDC found.\n");
 953                 return hp_sdc.dev_err;
 954         }
 955
 956         init_MUTEX_LOCKED(&tq_init_sem);
 957
 958         tq_init.actidx          = 0;
 959         tq_init.idx             = 1;
 960         tq_init.endidx          = 5;
 961         tq_init.seq             = tq_init_seq;
 962         tq_init.act.semaphore   = &tq_init_sem;
 963
 964         tq_init_seq[0] =
 965           HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN | HP_SDC_ACT_SEMAPHORE;
 966         tq_init_seq[1] = HP_SDC_CMD_READ_KCC;
 967         tq_init_seq[2] = 1;
 968         tq_init_seq[3] = 0;
 969         tq_init_seq[4] = 0;
 970
 971         hp_sdc_enqueue_transaction(&tq_init);
 972
 973         down(&tq_init_sem);
 974         up(&tq_init_sem);
 975
 976         if ((tq_init_seq[0] & HP_SDC_ACT_DEAD) == HP_SDC_ACT_DEAD) {
 977                 printk(KERN_WARNING PREFIX "Error reading config byte.\n");
 978                 hp_sdc_exit();
 979                 return -ENODEV;
 980         }
 981         hp_sdc.r11 = tq_init_seq[4];
 982         if (hp_sdc.r11 & HP_SDC_CFG_NEW) {
 983                 char *str;
 984                 printk(KERN_INFO PREFIX "New style SDC\n");
 985                 tq_init_seq[1] = HP_SDC_CMD_READ_XTD;
 986                 tq_init.actidx          = 0;
 987                 tq_init.idx             = 1;
 988                 down(&tq_init_sem);
 989                 hp_sdc_enqueue_transaction(&tq_init);
 990                 down(&tq_init_sem);
 991                 up(&tq_init_sem);
 992                 if ((tq_init_seq[0] & HP_SDC_ACT_DEAD) == HP_SDC_ACT_DEAD) {
 993                         printk(KERN_WARNING PREFIX "Error reading extended config byte.\n");
 994                         return -ENODEV;
 995                 }
 996                 hp_sdc.r7e = tq_init_seq[4];
 997                 HP_SDC_XTD_REV_STRINGS(hp_sdc.r7e & HP_SDC_XTD_REV, str)
 998                 printk(KERN_INFO PREFIX "Revision: %s\n", str);
 999                 if (hp_sdc.r7e & HP_SDC_XTD_BEEPER) {
1000                         printk(KERN_INFO PREFIX "TI SN76494 beeper present\n");
1001                 }
1002                 if (hp_sdc.r7e & HP_SDC_XTD_BBRTC) {
1003                         printk(KERN_INFO PREFIX "OKI MSM-58321 BBRTC present\n");
1004                 }
1005                 printk(KERN_INFO PREFIX "Spunking the self test register to force PUP "
1006                        "on next firmware reset.\n");
1007                 tq_init_seq[0] = HP_SDC_ACT_PRECMD |
1008                         HP_SDC_ACT_DATAOUT | HP_SDC_ACT_SEMAPHORE;
1009                 tq_init_seq[1] = HP_SDC_CMD_SET_STR;
1010                 tq_init_seq[2] = 1;
1011                 tq_init_seq[3] = 0;
1012                 tq_init.actidx          = 0;
1013                 tq_init.idx             = 1;
1014                 tq_init.endidx          = 4;
1015                 down(&tq_init_sem);
1016                 hp_sdc_enqueue_transaction(&tq_init);
1017                 down(&tq_init_sem);
1018                 up(&tq_init_sem);
1019         }
1020         else {
1021                 printk(KERN_INFO PREFIX "Old style SDC (1820-%s).\n",
1022                        (hp_sdc.r11 & HP_SDC_CFG_REV) ? "3300" : "2564/3087");
1023         }
1024
1025         return 0;
1026 }
1027
1028 module_init(hp_sdc_register);
1029 module_exit(hp_sdc_exit);
1030
1031 /* Timing notes:  These measurements taken on my 64MHz 7100-LC (715/64)
1032  *                                              cycles cycles-adj    time
1033  * between two consecutive mfctl(16)'s:              4        n/a    63ns
1034  * hp_sdc_spin_ibf when idle:                      119        115   1.7us
1035  * gsc_writeb status register:                      83         79   1.2us
1036  * IBF to clear after sending SET_IM:             6204       6006    93us
1037  * IBF to clear after sending LOAD_RT:            4467       4352    68us
1038  * IBF to clear after sending two LOAD_RTs:      18974      18859   295us
1039  * READ_T1, read status/data, IRQ, call handler: 35564        n/a   556us
1040  * cmd to ~IBF READ_T1 2nd time right after:   5158403        n/a    81ms
1041  * between IRQ received and ~IBF for above:    2578877        n/a    40ms
1042  *
1043  * Performance stats after a run of this module configuring HIL and
1044  * receiving a few mouse events:
1045  *
1046  * status in8  282508 cycles 7128 calls
1047  * status out8   8404 cycles  341 calls
1048  * data out8     1734 cycles   78 calls
1049  * isr         174324 cycles  617 calls (includes take)
1050  * take          1241 cycles    2 calls
1051  * put        1411504 cycles 6937 calls
1052  * task       1655209 cycles 6937 calls (includes put)
1053  *
1054  */