drivers/parport/parport_gsc.c

   1 /*
   2  *      Low-level parallel-support for PC-style hardware integrated in the
   3  *      LASI-Controller (on GSC-Bus) for HP-PARISC Workstations
   4  *
   5  *      This program is free software; you can redistribute it and/or modify
   6  *      it under the terms of the GNU General Public License as published by
   7  *      the Free Software Foundation; either version 2 of the License, or
   8  *      (at your option) any later version.
   9  *
  10  *      (C) 1999-2001 by Helge Deller <deller@gmx.de>
  11  *
  12  *
  13  * based on parport_pc.c by
  14  *          Grant Guenther <grant@torque.net>
  15  *          Phil Blundell <philb@gnu.org>
  16  *          Tim Waugh <tim@cyberelk.demon.co.uk>
  17  *          Jose Renau <renau@acm.org>
  18  *          David Campbell
  19  *          Andrea Arcangeli
  20  */
  21
  22 #undef DEBUG    /* undef for production */
  23
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26 #include <linux/delay.h>
  27 #include <linux/errno.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/ioport.h>
  30 #include <linux/kernel.h>
  31 #include <linux/slab.h>
  32 #include <linux/pci.h>
  33 #include <linux/sysctl.h>
  34
  35 #include <asm/io.h>
  36 #include <asm/dma.h>
  37 #include <linux/uaccess.h>
  38 #include <asm/superio.h>
  39
  40 #include <linux/parport.h>
  41 #include <asm/pdc.h>
  42 #include <asm/parisc-device.h>
  43 #include <asm/hardware.h>
  44 #include "parport_gsc.h"
  45
  46
  47 MODULE_AUTHOR("Helge Deller <deller@gmx.de>");
  48 MODULE_DESCRIPTION("HP-PARISC PC-style parallel port driver");
  49 MODULE_SUPPORTED_DEVICE("integrated PC-style parallel port");
  50 MODULE_LICENSE("GPL");
  51
  52
  53 /*
  54  * Clear TIMEOUT BIT in EPP MODE
  55  *
  56  * This is also used in SPP detection.
  57  */
  58 static int clear_epp_timeout(struct parport *pb)
  59 {
  60         unsigned char r;
  61
  62         if (!(parport_gsc_read_status(pb) & 0x01))
  63                 return 1;
  64
  65         /* To clear timeout some chips require double read */
  66         parport_gsc_read_status(pb);
  67         r = parport_gsc_read_status(pb);
  68         parport_writeb (r | 0x01, STATUS (pb)); /* Some reset by writing 1 */
  69         parport_writeb (r & 0xfe, STATUS (pb)); /* Others by writing 0 */
  70         r = parport_gsc_read_status(pb);
  71
  72         return !(r & 0x01);
  73 }
  74
  75 /*
  76  * Access functions.
  77  *
  78  * Most of these aren't static because they may be used by the
  79  * parport_xxx_yyy macros.  extern __inline__ versions of several
  80  * of these are in parport_gsc.h.
  81  */
  82
  83 void parport_gsc_init_state(struct pardevice *dev, struct parport_state *s)
  84 {
  85         s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
  86 }
  87
  88 void parport_gsc_save_state(struct parport *p, struct parport_state *s)
  89 {
  90         s->u.pc.ctr = parport_readb (CONTROL (p));
  91 }
  92
  93 void parport_gsc_restore_state(struct parport *p, struct parport_state *s)
  94 {
  95         parport_writeb (s->u.pc.ctr, CONTROL (p));
  96 }
  97
  98 struct parport_operations parport_gsc_ops =
  99 {
 100         .write_data     = parport_gsc_write_data,
 101         .read_data      = parport_gsc_read_data,
 102
 103         .write_control  = parport_gsc_write_control,
 104         .read_control   = parport_gsc_read_control,
 105         .frob_control   = parport_gsc_frob_control,
 106
 107         .read_status    = parport_gsc_read_status,
 108
 109         .enable_irq     = parport_gsc_enable_irq,
 110         .disable_irq    = parport_gsc_disable_irq,
 111
 112         .data_forward   = parport_gsc_data_forward,
 113         .data_reverse   = parport_gsc_data_reverse,
 114
 115         .init_state     = parport_gsc_init_state,
 116         .save_state     = parport_gsc_save_state,
 117         .restore_state  = parport_gsc_restore_state,
 118
 119         .epp_write_data = parport_ieee1284_epp_write_data,
 120         .epp_read_data  = parport_ieee1284_epp_read_data,
 121         .epp_write_addr = parport_ieee1284_epp_write_addr,
 122         .epp_read_addr  = parport_ieee1284_epp_read_addr,
 123
 124         .ecp_write_data = parport_ieee1284_ecp_write_data,
 125         .ecp_read_data  = parport_ieee1284_ecp_read_data,
 126         .ecp_write_addr = parport_ieee1284_ecp_write_addr,
 127
 128         .compat_write_data      = parport_ieee1284_write_compat,
 129         .nibble_read_data       = parport_ieee1284_read_nibble,
 130         .byte_read_data         = parport_ieee1284_read_byte,
 131
 132         .owner          = THIS_MODULE,
 133 };
 134
 135 /* --- Mode detection ------------------------------------- */
 136
 137 /*
 138  * Checks for port existence, all ports support SPP MODE
 139  */
 140 static int parport_SPP_supported(struct parport *pb)
 141 {
 142         unsigned char r, w;
 143
 144         /*
 145          * first clear an eventually pending EPP timeout
 146          * I (sailer@ife.ee.ethz.ch) have an SMSC chipset
 147          * that does not even respond to SPP cycles if an EPP
 148          * timeout is pending
 149          */
 150         clear_epp_timeout(pb);
 151
 152         /* Do a simple read-write test to make sure the port exists. */
 153         w = 0xc;
 154         parport_writeb (w, CONTROL (pb));
 155
 156         /* Is there a control register that we can read from?  Some
 157          * ports don't allow reads, so read_control just returns a
 158          * software copy. Some ports _do_ allow reads, so bypass the
 159          * software copy here.  In addition, some bits aren't
 160          * writable. */
 161         r = parport_readb (CONTROL (pb));
 162         if ((r & 0xf) == w) {
 163                 w = 0xe;
 164                 parport_writeb (w, CONTROL (pb));
 165                 r = parport_readb (CONTROL (pb));
 166                 parport_writeb (0xc, CONTROL (pb));
 167                 if ((r & 0xf) == w)
 168                         return PARPORT_MODE_PCSPP;
 169         }
 170
 171         /* Try the data register.  The data lines aren't tri-stated at
 172          * this stage, so we expect back what we wrote. */
 173         w = 0xaa;
 174         parport_gsc_write_data (pb, w);
 175         r = parport_gsc_read_data (pb);
 176         if (r == w) {
 177                 w = 0x55;
 178                 parport_gsc_write_data (pb, w);
 179                 r = parport_gsc_read_data (pb);
 180                 if (r == w)
 181                         return PARPORT_MODE_PCSPP;
 182         }
 183
 184         return 0;
 185 }
 186
 187 /* Detect PS/2 support.
 188  *
 189  * Bit 5 (0x20) sets the PS/2 data direction; setting this high
 190  * allows us to read data from the data lines.  In theory we would get back
 191  * 0xff but any peripheral attached to the port may drag some or all of the
 192  * lines down to zero.  So if we get back anything that isn't the contents
 193  * of the data register we deem PS/2 support to be present.
 194  *
 195  * Some SPP ports have "half PS/2" ability - you can't turn off the line
 196  * drivers, but an external peripheral with sufficiently beefy drivers of
 197  * its own can overpower them and assert its own levels onto the bus, from
 198  * where they can then be read back as normal.  Ports with this property
 199  * and the right type of device attached are likely to fail the SPP test,
 200  * (as they will appear to have stuck bits) and so the fact that they might
 201  * be misdetected here is rather academic.
 202  */
 203
 204 static int parport_PS2_supported(struct parport *pb)
 205 {
 206         int ok = 0;
 207
 208         clear_epp_timeout(pb);
 209
 210         /* try to tri-state the buffer */
 211         parport_gsc_data_reverse (pb);
 212
 213         parport_gsc_write_data(pb, 0x55);
 214         if (parport_gsc_read_data(pb) != 0x55) ok++;
 215
 216         parport_gsc_write_data(pb, 0xaa);
 217         if (parport_gsc_read_data(pb) != 0xaa) ok++;
 218
 219         /* cancel input mode */
 220         parport_gsc_data_forward (pb);
 221
 222         if (ok) {
 223                 pb->modes |= PARPORT_MODE_TRISTATE;
 224         } else {
 225                 struct parport_gsc_private *priv = pb->private_data;
 226                 priv->ctr_writable &= ~0x20;
 227         }
 228
 229         return ok;
 230 }
 231
 232
 233 /* --- Initialisation code -------------------------------- */
 234
 235 struct parport *parport_gsc_probe_port(unsigned long base,
 236                                        unsigned long base_hi, int irq,
 237                                        int dma, struct parisc_device *padev)
 238 {
 239         struct parport_gsc_private *priv;
 240         struct parport_operations *ops;
 241         struct parport tmp;
 242         struct parport *p = &tmp;
 243
 244         priv = kzalloc (sizeof (struct parport_gsc_private), GFP_KERNEL);
 245         if (!priv) {
 246                 printk (KERN_DEBUG "parport (0x%lx): no memory!\n", base);
 247                 return NULL;
 248         }
 249         ops = kmemdup(&parport_gsc_ops, sizeof(struct parport_operations),
 250                       GFP_KERNEL);
 251         if (!ops) {
 252                 printk (KERN_DEBUG "parport (0x%lx): no memory for ops!\n",
 253                         base);
 254                 kfree (priv);
 255                 return NULL;
 256         }
 257         priv->ctr = 0xc;
 258         priv->ctr_writable = 0xff;
 259         priv->dma_buf = 0;
 260         priv->dma_handle = 0;
 261         p->base = base;
 262         p->base_hi = base_hi;
 263         p->irq = irq;
 264         p->dma = dma;
 265         p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT;
 266         p->ops = ops;
 267         p->private_data = priv;
 268         p->physport = p;
 269         if (!parport_SPP_supported (p)) {
 270                 /* No port. */
 271                 kfree (priv);
 272                 kfree(ops);
 273                 return NULL;
 274         }
 275         parport_PS2_supported (p);
 276
 277         if (!(p = parport_register_port(base, PARPORT_IRQ_NONE,
 278                                         PARPORT_DMA_NONE, ops))) {
 279                 kfree (priv);
 280                 kfree (ops);
 281                 return NULL;
 282         }
 283
 284         p->dev = &padev->dev;
 285         p->base_hi = base_hi;
 286         p->modes = tmp.modes;
 287         p->size = (p->modes & PARPORT_MODE_EPP)?8:3;
 288         p->private_data = priv;
 289
 290         printk(KERN_INFO "%s: PC-style at 0x%lx", p->name, p->base);
 291         p->irq = irq;
 292         if (p->irq == PARPORT_IRQ_AUTO) {
 293                 p->irq = PARPORT_IRQ_NONE;
 294         }
 295         if (p->irq != PARPORT_IRQ_NONE) {
 296                 pr_cont(", irq %d", p->irq);
 297
 298                 if (p->dma == PARPORT_DMA_AUTO) {
 299                         p->dma = PARPORT_DMA_NONE;
 300                 }
 301         }
 302         if (p->dma == PARPORT_DMA_AUTO) /* To use DMA, giving the irq
 303                                            is mandatory (see above) */
 304                 p->dma = PARPORT_DMA_NONE;
 305
 306         pr_cont(" [");
 307 #define printmode(x) {if(p->modes&PARPORT_MODE_##x){pr_cont("%s%s",f?",":"",#x);f++;}}
 308         {
 309                 int f = 0;
 310                 printmode(PCSPP);
 311                 printmode(TRISTATE);
 312                 printmode(COMPAT)
 313                 printmode(EPP);
 314 //              printmode(ECP);
 315 //              printmode(DMA);
 316         }
 317 #undef printmode
 318         pr_cont("]\n");
 319
 320         if (p->irq != PARPORT_IRQ_NONE) {
 321                 if (request_irq (p->irq, parport_irq_handler,
 322                                  0, p->name, p)) {
 323                         printk (KERN_WARNING "%s: irq %d in use, "
 324                                 "resorting to polled operation\n",
 325                                 p->name, p->irq);
 326                         p->irq = PARPORT_IRQ_NONE;
 327                         p->dma = PARPORT_DMA_NONE;
 328                 }
 329         }
 330
 331         /* Done probing.  Now put the port into a sensible start-up state. */
 332
 333         parport_gsc_write_data(p, 0);
 334         parport_gsc_data_forward (p);
 335
 336         /* Now that we've told the sharing engine about the port, and
 337            found out its characteristics, let the high-level drivers
 338            know about it. */
 339         parport_announce_port (p);
 340
 341         return p;
 342 }
 343
 344
 345 #define PARPORT_GSC_OFFSET 0x800
 346
 347 static int parport_count;
 348
 349 static int __init parport_init_chip(struct parisc_device *dev)
 350 {
 351         struct parport *p;
 352         unsigned long port;
 353
 354         if (!dev->irq) {
 355                 printk(KERN_WARNING "IRQ not found for parallel device at 0x%llx\n",
 356                         (unsigned long long)dev->hpa.start);
 357                 return -ENODEV;
 358         }
 359
 360         port = dev->hpa.start + PARPORT_GSC_OFFSET;
 361
 362         /* some older machines with ASP-chip don't support
 363          * the enhanced parport modes.
 364          */
 365         if (boot_cpu_data.cpu_type > pcxt && !pdc_add_valid(port+4)) {
 366
 367                 /* Initialize bidirectional-mode (0x10) & data-tranfer-mode #1 (0x20) */
 368                 printk("%s: initialize bidirectional-mode.\n", __func__);
 369                 parport_writeb ( (0x10 + 0x20), port + 4);
 370
 371         } else {
 372                 printk("%s: enhanced parport-modes not supported.\n", __func__);
 373         }
 374
 375         p = parport_gsc_probe_port(port, 0, dev->irq,
 376                         /* PARPORT_IRQ_NONE */ PARPORT_DMA_NONE, dev);
 377         if (p)
 378                 parport_count++;
 379         dev_set_drvdata(&dev->dev, p);
 380
 381         return 0;
 382 }
 383
 384 static int __exit parport_remove_chip(struct parisc_device *dev)
 385 {
 386         struct parport *p = dev_get_drvdata(&dev->dev);
 387         if (p) {
 388                 struct parport_gsc_private *priv = p->private_data;
 389                 struct parport_operations *ops = p->ops;
 390                 parport_remove_port(p);
 391                 if (p->dma != PARPORT_DMA_NONE)
 392                         free_dma(p->dma);
 393                 if (p->irq != PARPORT_IRQ_NONE)
 394                         free_irq(p->irq, p);
 395                 if (priv->dma_buf)
 396                         pci_free_consistent(priv->dev, PAGE_SIZE,
 397                                             priv->dma_buf,
 398                                             priv->dma_handle);
 399                 kfree (p->private_data);
 400                 parport_put_port(p);
 401                 kfree (ops); /* hope no-one cached it */
 402         }
 403         return 0;
 404 }
 405
 406 static const struct parisc_device_id parport_tbl[] __initconst = {
 407         { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x74 },
 408         { 0, }
 409 };
 410
 411 MODULE_DEVICE_TABLE(parisc, parport_tbl);
 412
 413 static struct parisc_driver parport_driver __refdata = {
 414         .name           = "Parallel",
 415         .id_table       = parport_tbl,
 416         .probe          = parport_init_chip,
 417         .remove         = __exit_p(parport_remove_chip),
 418 };
 419
 420 int parport_gsc_init(void)
 421 {
 422         return register_parisc_driver(&parport_driver);
 423 }
 424
 425 static void parport_gsc_exit(void)
 426 {
 427         unregister_parisc_driver(&parport_driver);
 428 }
 429
 430 module_init(parport_gsc_init);
 431 module_exit(parport_gsc_exit);