drivers/input/serio/hp_sdc_mlc.c

   1 /*
   2  * Access to HP-HIL MLC through HP System Device Controller.
   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  * HP-HIL Technical Reference Manual.  Hewlett Packard Product No. 45918A
  31  * System Device Controller Microprocessor Firmware Theory of Operation
  32  *      for Part Number 1820-4784 Revision B.  Dwg No. A-1820-4784-2
  33  *
  34  */
  35
  36 #include <linux/hil_mlc.h>
  37 #include <linux/hp_sdc.h>
  38 #include <linux/errno.h>
  39 #include <linux/kernel.h>
  40 #include <linux/module.h>
  41 #include <linux/init.h>
  42 #include <linux/string.h>
  43 #include <asm/semaphore.h>
  44
  45 #define PREFIX "HP SDC MLC: "
  46
  47 static hil_mlc hp_sdc_mlc;
  48
  49 MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
  50 MODULE_DESCRIPTION("Glue for onboard HIL MLC in HP-PARISC machines");
  51 MODULE_LICENSE("Dual BSD/GPL");
  52
  53 struct hp_sdc_mlc_priv_s {
  54         int emtestmode;
  55         hp_sdc_transaction trans;
  56         u8 tseq[16];
  57         int got5x;
  58 } hp_sdc_mlc_priv;
  59
  60 /************************* Interrupt context ******************************/
  61 static void hp_sdc_mlc_isr (int irq, void *dev_id,
  62                             uint8_t status, uint8_t data) {
  63         int idx;
  64         hil_mlc *mlc = &hp_sdc_mlc;
  65
  66         write_lock(&(mlc->lock));
  67         if (mlc->icount < 0) {
  68                 printk(KERN_WARNING PREFIX "HIL Overflow!\n");
  69                 up(&mlc->isem);
  70                 goto out;
  71         }
  72         idx = 15 - mlc->icount;
  73         if ((status & HP_SDC_STATUS_IRQMASK) == HP_SDC_STATUS_HILDATA) {
  74                 mlc->ipacket[idx] |= data | HIL_ERR_INT;
  75                 mlc->icount--;
  76                 if (hp_sdc_mlc_priv.got5x) goto check;
  77                 if (!idx) goto check;
  78                 if ((mlc->ipacket[idx-1] & HIL_PKT_ADDR_MASK) !=
  79                     (mlc->ipacket[idx] & HIL_PKT_ADDR_MASK)) {
  80                         mlc->ipacket[idx] &= ~HIL_PKT_ADDR_MASK;
  81                         mlc->ipacket[idx] |= (mlc->ipacket[idx-1]
  82                                                     & HIL_PKT_ADDR_MASK);
  83                 }
  84                 goto check;
  85         }
  86         /* We know status is 5X */
  87         if (data & HP_SDC_HIL_ISERR) goto err;
  88         mlc->ipacket[idx] =
  89                 (data & HP_SDC_HIL_R1MASK) << HIL_PKT_ADDR_SHIFT;
  90         hp_sdc_mlc_priv.got5x = 1;
  91         goto out;
  92
  93  check:
  94         hp_sdc_mlc_priv.got5x = 0;
  95         if (mlc->imatch == 0) goto done;
  96         if ((mlc->imatch == (HIL_ERR_INT | HIL_PKT_CMD | HIL_CMD_POL))
  97             && (mlc->ipacket[idx] == (mlc->imatch | idx))) goto done;
  98         if (mlc->ipacket[idx] == mlc->imatch) goto done;
  99         goto out;
 100
 101  err:
 102         printk(KERN_DEBUG PREFIX "err code %x\n", data);
 103         switch (data) {
 104         case HP_SDC_HIL_RC_DONE:
 105                 printk(KERN_WARNING PREFIX "Bastard SDC reconfigured loop!\n");
 106                 break;
 107         case HP_SDC_HIL_ERR:
 108                 mlc->ipacket[idx] |= HIL_ERR_INT | HIL_ERR_PERR |
 109                   HIL_ERR_FERR | HIL_ERR_FOF;
 110                 break;
 111         case HP_SDC_HIL_TO:
 112                 mlc->ipacket[idx] |= HIL_ERR_INT | HIL_ERR_LERR;
 113                 break;
 114         case HP_SDC_HIL_RC:
 115                 printk(KERN_WARNING PREFIX "Bastard SDC decided to reconfigure loop!\n");
 116                 break;
 117         default:
 118                 printk(KERN_WARNING PREFIX "Unkown HIL Error status (%x)!\n", data);
 119                 break;
 120         }
 121         /* No more data will be coming due to an error. */
 122  done:
 123         tasklet_schedule(mlc->tasklet);
 124         up(&(mlc->isem));
 125  out:
 126         write_unlock(&(mlc->lock));
 127 }
 128
 129
 130 /******************** Tasklet or userspace context functions ****************/
 131
 132 static int hp_sdc_mlc_in (hil_mlc *mlc, suseconds_t timeout) {
 133         unsigned long flags;
 134         struct hp_sdc_mlc_priv_s *priv;
 135         int rc = 2;
 136
 137         priv = mlc->priv;
 138
 139         write_lock_irqsave(&(mlc->lock), flags);
 140
 141         /* Try to down the semaphore */
 142         if (down_trylock(&(mlc->isem))) {
 143                 struct timeval tv;
 144                 if (priv->emtestmode) {
 145                         mlc->ipacket[0] =
 146                                 HIL_ERR_INT | (mlc->opacket &
 147                                                (HIL_PKT_CMD |
 148                                                 HIL_PKT_ADDR_MASK |
 149                                                 HIL_PKT_DATA_MASK));
 150                         mlc->icount = 14;
 151                         /* printk(KERN_DEBUG PREFIX ">[%x]\n", mlc->ipacket[0]); */
 152                         goto wasup;
 153                 }
 154                 do_gettimeofday(&tv);
 155                 tv.tv_usec += 1000000 * (tv.tv_sec - mlc->instart.tv_sec);
 156                 if (tv.tv_usec - mlc->instart.tv_usec > mlc->intimeout) {
 157                   /*              printk("!%i %i",
 158                                   tv.tv_usec - mlc->instart.tv_usec,
 159                                   mlc->intimeout);
 160                   */
 161                         rc = 1;
 162                         up(&(mlc->isem));
 163                 }
 164                 goto done;
 165         }
 166  wasup:
 167         up(&(mlc->isem));
 168         rc = 0;
 169         goto done;
 170  done:
 171         write_unlock_irqrestore(&(mlc->lock), flags);
 172         return rc;
 173 }
 174
 175 static int hp_sdc_mlc_cts (hil_mlc *mlc) {
 176         struct hp_sdc_mlc_priv_s *priv;
 177         unsigned long flags;
 178
 179         priv = mlc->priv;
 180
 181         write_lock_irqsave(&(mlc->lock), flags);
 182
 183         /* Try to down the semaphores -- they should be up. */
 184         if (down_trylock(&(mlc->isem))) {
 185                 BUG();
 186                 goto busy;
 187         }
 188         if (down_trylock(&(mlc->osem))) {
 189                 BUG();
 190                 up(&(mlc->isem));
 191                 goto busy;
 192         }
 193         up(&(mlc->isem));
 194         up(&(mlc->osem));
 195
 196         if (down_trylock(&(mlc->csem))) {
 197                 if (priv->trans.act.semaphore != &(mlc->csem)) goto poll;
 198                 goto busy;
 199         }
 200         if (!(priv->tseq[4] & HP_SDC_USE_LOOP)) goto done;
 201
 202  poll:
 203         priv->trans.act.semaphore = &(mlc->csem);
 204         priv->trans.actidx = 0;
 205         priv->trans.idx = 1;
 206         priv->trans.endidx = 5;
 207         priv->tseq[0] =
 208                 HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN | HP_SDC_ACT_SEMAPHORE;
 209         priv->tseq[1] = HP_SDC_CMD_READ_USE;
 210         priv->tseq[2] = 1;
 211         priv->tseq[3] = 0;
 212         priv->tseq[4] = 0;
 213         hp_sdc_enqueue_transaction(&(priv->trans));
 214  busy:
 215         write_unlock_irqrestore(&(mlc->lock), flags);
 216         return 1;
 217  done:
 218         priv->trans.act.semaphore = &(mlc->osem);
 219         up(&(mlc->csem));
 220         write_unlock_irqrestore(&(mlc->lock), flags);
 221         return 0;
 222 }
 223
 224 static void hp_sdc_mlc_out (hil_mlc *mlc) {
 225         struct hp_sdc_mlc_priv_s *priv;
 226         unsigned long flags;
 227
 228         priv = mlc->priv;
 229
 230         write_lock_irqsave(&(mlc->lock), flags);
 231
 232         /* Try to down the semaphore -- it should be up. */
 233         if (down_trylock(&(mlc->osem))) {
 234                 BUG();
 235                 goto done;
 236         }
 237
 238         if (mlc->opacket & HIL_DO_ALTER_CTRL) goto do_control;
 239
 240  do_data:
 241         if (priv->emtestmode) {
 242                 up(&(mlc->osem));
 243                 goto done;
 244         }
 245         /* Shouldn't be sending commands when loop may be busy */
 246         if (down_trylock(&(mlc->csem))) {
 247                 BUG();
 248                 goto done;
 249         }
 250         up(&(mlc->csem));
 251
 252         priv->trans.actidx = 0;
 253         priv->trans.idx = 1;
 254         priv->trans.act.semaphore = &(mlc->osem);
 255         priv->trans.endidx = 6;
 256         priv->tseq[0] =
 257                 HP_SDC_ACT_DATAREG | HP_SDC_ACT_POSTCMD | HP_SDC_ACT_SEMAPHORE;
 258         priv->tseq[1] = 0x7;
 259         priv->tseq[2] =
 260                 (mlc->opacket &
 261                  (HIL_PKT_ADDR_MASK | HIL_PKT_CMD))
 262                    >> HIL_PKT_ADDR_SHIFT;
 263         priv->tseq[3] =
 264                 (mlc->opacket & HIL_PKT_DATA_MASK)
 265                   >> HIL_PKT_DATA_SHIFT;
 266         priv->tseq[4] = 0;  /* No timeout */
 267         if (priv->tseq[3] == HIL_CMD_DHR) priv->tseq[4] = 1;
 268         priv->tseq[5] = HP_SDC_CMD_DO_HIL;
 269         goto enqueue;
 270
 271  do_control:
 272         priv->emtestmode = mlc->opacket & HIL_CTRL_TEST;
 273
 274         /* we cannot emulate this, it should not be used. */
 275         BUG_ON((mlc->opacket & (HIL_CTRL_APE | HIL_CTRL_IPF)) == HIL_CTRL_APE);
 276
 277         if ((mlc->opacket & HIL_CTRL_ONLY) == HIL_CTRL_ONLY) goto control_only;
 278         if (mlc->opacket & HIL_CTRL_APE) {
 279                 BUG(); /* Should not send command/data after engaging APE */
 280                 goto done;
 281         }
 282         /* Disengaging APE this way would not be valid either since
 283          * the loop must be allowed to idle.
 284          *
 285          * So, it works out that we really never actually send control
 286          * and data when using SDC, we just send the data.
 287          */
 288         goto do_data;
 289
 290  control_only:
 291         priv->trans.actidx = 0;
 292         priv->trans.idx = 1;
 293         priv->trans.act.semaphore = &(mlc->osem);
 294         priv->trans.endidx = 4;
 295         priv->tseq[0] =
 296           HP_SDC_ACT_PRECMD | HP_SDC_ACT_DATAOUT | HP_SDC_ACT_SEMAPHORE;
 297         priv->tseq[1] = HP_SDC_CMD_SET_LPC;
 298         priv->tseq[2] = 1;
 299         //      priv->tseq[3] = (mlc->ddc + 1) | HP_SDC_LPS_ACSUCC;
 300         priv->tseq[3] = 0;
 301         if (mlc->opacket & HIL_CTRL_APE) {
 302                 priv->tseq[3] |= HP_SDC_LPC_APE_IPF;
 303                 down_trylock(&(mlc->csem));
 304         }
 305  enqueue:
 306         hp_sdc_enqueue_transaction(&(priv->trans));
 307  done:
 308         write_unlock_irqrestore(&(mlc->lock), flags);
 309 }
 310
 311 static int __init hp_sdc_mlc_init(void)
 312 {
 313         hil_mlc *mlc = &hp_sdc_mlc;
 314
 315         printk(KERN_INFO PREFIX "Registering the System Domain Controller's HIL MLC.\n");
 316
 317         hp_sdc_mlc_priv.emtestmode = 0;
 318         hp_sdc_mlc_priv.trans.seq = hp_sdc_mlc_priv.tseq;
 319         hp_sdc_mlc_priv.trans.act.semaphore = &(mlc->osem);
 320         hp_sdc_mlc_priv.got5x = 0;
 321
 322         mlc->cts                = &hp_sdc_mlc_cts;
 323         mlc->in                 = &hp_sdc_mlc_in;
 324         mlc->out                = &hp_sdc_mlc_out;
 325
 326         if (hil_mlc_register(mlc)) {
 327                 printk(KERN_WARNING PREFIX "Failed to register MLC structure with hil_mlc\n");
 328                 goto err0;
 329         }
 330         mlc->priv               = &hp_sdc_mlc_priv;
 331
 332         if (hp_sdc_request_hil_irq(&hp_sdc_mlc_isr)) {
 333                 printk(KERN_WARNING PREFIX "Request for raw HIL ISR hook denied\n");
 334                 goto err1;
 335         }
 336         return 0;
 337  err1:
 338         if (hil_mlc_unregister(mlc)) {
 339                 printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
 340                         "This is bad.  Could cause an oops.\n");
 341         }
 342  err0:
 343         return -EBUSY;
 344 }
 345
 346 static void __exit hp_sdc_mlc_exit(void)
 347 {
 348         hil_mlc *mlc = &hp_sdc_mlc;
 349         if (hp_sdc_release_hil_irq(&hp_sdc_mlc_isr)) {
 350                 printk(KERN_ERR PREFIX "Failed to release the raw HIL ISR hook.\n"
 351                         "This is bad.  Could cause an oops.\n");
 352         }
 353         if (hil_mlc_unregister(mlc)) {
 354                 printk(KERN_ERR PREFIX "Failed to unregister MLC structure with hil_mlc.\n"
 355                         "This is bad.  Could cause an oops.\n");
 356         }
 357 }
 358
 359 module_init(hp_sdc_mlc_init);
 360 module_exit(hp_sdc_mlc_exit);