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