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