drivers/parport/parport

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This source file includes following definitions.
clear_epp_timeout
parport_gsc_init_state
parport_gsc_save_state
parport_gsc_restore_state
parport_SPP_supported
parport_PS2_supported
parport_gsc_probe_port
parport_init_chip
parport_remove_chip
parport_gsc_init
parport_gsc_exit
   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      Low-level parallel-support for PC-style hardware integrated in the 
   4  *      LASI-Controller (on GSC-Bus) for HP-PARISC Workstations
   5  *
   6  *      (C) 1999-2001 by Helge Deller <deller@gmx.de>
   7  * 
   8  * based on parport_pc.c by 
   9  *          Grant Guenther <grant@torque.net>
  10  *          Phil Blundell <philb@gnu.org>
  11  *          Tim Waugh <tim@cyberelk.demon.co.uk>
  12  *          Jose Renau <renau@acm.org>
  13  *          David Campbell
  14  *          Andrea Arcangeli
  15  */
  16 
  17 #undef DEBUG    /* undef for production */
  18 
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/delay.h>
  22 #include <linux/errno.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/ioport.h>
  25 #include <linux/kernel.h>
  26 #include <linux/slab.h>
  27 #include <linux/pci.h>
  28 #include <linux/sysctl.h>
  29 
  30 #include <asm/io.h>
  31 #include <asm/dma.h>
  32 #include <linux/uaccess.h>
  33 #include <asm/superio.h>
  34 
  35 #include <linux/parport.h>
  36 #include <asm/pdc.h>
  37 #include <asm/parisc-device.h>
  38 #include <asm/hardware.h>
  39 #include "parport_gsc.h"
  40 
  41 
  42 MODULE_AUTHOR("Helge Deller <deller@gmx.de>");
  43 MODULE_DESCRIPTION("HP-PARISC PC-style parallel port driver");
  44 MODULE_SUPPORTED_DEVICE("integrated PC-style parallel port");
  45 MODULE_LICENSE("GPL");
  46 
  47 
  48 /*
  49  * Clear TIMEOUT BIT in EPP MODE
  50  *
  51  * This is also used in SPP detection.
  52  */
  53 static int clear_epp_timeout(struct parport *pb)
  54 {
  55         unsigned char r;
  56 
  57         if (!(parport_gsc_read_status(pb) & 0x01))
  58                 return 1;
  59 
  60         /* To clear timeout some chips require double read */
  61         parport_gsc_read_status(pb);
  62         r = parport_gsc_read_status(pb);
  63         parport_writeb (r | 0x01, STATUS (pb)); /* Some reset by writing 1 */
  64         parport_writeb (r & 0xfe, STATUS (pb)); /* Others by writing 0 */
  65         r = parport_gsc_read_status(pb);
  66 
  67         return !(r & 0x01);
  68 }
  69 
  70 /*
  71  * Access functions.
  72  *
  73  * Most of these aren't static because they may be used by the
  74  * parport_xxx_yyy macros.  extern __inline__ versions of several
  75  * of these are in parport_gsc.h.
  76  */
  77 
  78 void parport_gsc_init_state(struct pardevice *dev, struct parport_state *s)
  79 {
  80         s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
  81 }
  82 
  83 void parport_gsc_save_state(struct parport *p, struct parport_state *s)
  84 {
  85         s->u.pc.ctr = parport_readb (CONTROL (p));
  86 }
  87 
  88 void parport_gsc_restore_state(struct parport *p, struct parport_state *s)
  89 {
  90         parport_writeb (s->u.pc.ctr, CONTROL (p));
  91 }
  92 
  93 struct parport_operations parport_gsc_ops = 
  94 {
  95         .write_data     = parport_gsc_write_data,
  96         .read_data      = parport_gsc_read_data,
  97 
  98         .write_control  = parport_gsc_write_control,
  99         .read_control   = parport_gsc_read_control,
 100         .frob_control   = parport_gsc_frob_control,
 101 
 102         .read_status    = parport_gsc_read_status,
 103 
 104         .enable_irq     = parport_gsc_enable_irq,
 105         .disable_irq    = parport_gsc_disable_irq,
 106 
 107         .data_forward   = parport_gsc_data_forward,
 108         .data_reverse   = parport_gsc_data_reverse,
 109 
 110         .init_state     = parport_gsc_init_state,
 111         .save_state     = parport_gsc_save_state,
 112         .restore_state  = parport_gsc_restore_state,
 113 
 114         .epp_write_data = parport_ieee1284_epp_write_data,
 115         .epp_read_data  = parport_ieee1284_epp_read_data,
 116         .epp_write_addr = parport_ieee1284_epp_write_addr,
 117         .epp_read_addr  = parport_ieee1284_epp_read_addr,
 118 
 119         .ecp_write_data = parport_ieee1284_ecp_write_data,
 120         .ecp_read_data  = parport_ieee1284_ecp_read_data,
 121         .ecp_write_addr = parport_ieee1284_ecp_write_addr,
 122 
 123         .compat_write_data      = parport_ieee1284_write_compat,
 124         .nibble_read_data       = parport_ieee1284_read_nibble,
 125         .byte_read_data         = parport_ieee1284_read_byte,
 126 
 127         .owner          = THIS_MODULE,
 128 };
 129 
 130 /* --- Mode detection ------------------------------------- */
 131 
 132 /*
 133  * Checks for port existence, all ports support SPP MODE
 134  */
 135 static int parport_SPP_supported(struct parport *pb)
 136 {
 137         unsigned char r, w;
 138 
 139         /*
 140          * first clear an eventually pending EPP timeout 
 141          * I (sailer@ife.ee.ethz.ch) have an SMSC chipset
 142          * that does not even respond to SPP cycles if an EPP
 143          * timeout is pending
 144          */
 145         clear_epp_timeout(pb);
 146 
 147         /* Do a simple read-write test to make sure the port exists. */
 148         w = 0xc;
 149         parport_writeb (w, CONTROL (pb));
 150 
 151         /* Is there a control register that we can read from?  Some
 152          * ports don't allow reads, so read_control just returns a
 153          * software copy. Some ports _do_ allow reads, so bypass the
 154          * software copy here.  In addition, some bits aren't
 155          * writable. */
 156         r = parport_readb (CONTROL (pb));
 157         if ((r & 0xf) == w) {
 158                 w = 0xe;
 159                 parport_writeb (w, CONTROL (pb));
 160                 r = parport_readb (CONTROL (pb));
 161                 parport_writeb (0xc, CONTROL (pb));
 162                 if ((r & 0xf) == w)
 163                         return PARPORT_MODE_PCSPP;
 164         }
 165 
 166         /* Try the data register.  The data lines aren't tri-stated at
 167          * this stage, so we expect back what we wrote. */
 168         w = 0xaa;
 169         parport_gsc_write_data (pb, w);
 170         r = parport_gsc_read_data (pb);
 171         if (r == w) {
 172                 w = 0x55;
 173                 parport_gsc_write_data (pb, w);
 174                 r = parport_gsc_read_data (pb);
 175                 if (r == w)
 176                         return PARPORT_MODE_PCSPP;
 177         }
 178 
 179         return 0;
 180 }
 181 
 182 /* Detect PS/2 support.
 183  *
 184  * Bit 5 (0x20) sets the PS/2 data direction; setting this high
 185  * allows us to read data from the data lines.  In theory we would get back
 186  * 0xff but any peripheral attached to the port may drag some or all of the
 187  * lines down to zero.  So if we get back anything that isn't the contents
 188  * of the data register we deem PS/2 support to be present. 
 189  *
 190  * Some SPP ports have "half PS/2" ability - you can't turn off the line
 191  * drivers, but an external peripheral with sufficiently beefy drivers of
 192  * its own can overpower them and assert its own levels onto the bus, from
 193  * where they can then be read back as normal.  Ports with this property
 194  * and the right type of device attached are likely to fail the SPP test,
 195  * (as they will appear to have stuck bits) and so the fact that they might
 196  * be misdetected here is rather academic. 
 197  */
 198 
 199 static int parport_PS2_supported(struct parport *pb)
 200 {
 201         int ok = 0;
 202   
 203         clear_epp_timeout(pb);
 204 
 205         /* try to tri-state the buffer */
 206         parport_gsc_data_reverse (pb);
 207         
 208         parport_gsc_write_data(pb, 0x55);
 209         if (parport_gsc_read_data(pb) != 0x55) ok++;
 210 
 211         parport_gsc_write_data(pb, 0xaa);
 212         if (parport_gsc_read_data(pb) != 0xaa) ok++;
 213 
 214         /* cancel input mode */
 215         parport_gsc_data_forward (pb);
 216 
 217         if (ok) {
 218                 pb->modes |= PARPORT_MODE_TRISTATE;
 219         } else {
 220                 struct parport_gsc_private *priv = pb->private_data;
 221                 priv->ctr_writable &= ~0x20;
 222         }
 223 
 224         return ok;
 225 }
 226 
 227 
 228 /* --- Initialisation code -------------------------------- */
 229 
 230 struct parport *parport_gsc_probe_port(unsigned long base,
 231                                        unsigned long base_hi, int irq,
 232                                        int dma, struct parisc_device *padev)
 233 {
 234         struct parport_gsc_private *priv;
 235         struct parport_operations *ops;
 236         struct parport tmp;
 237         struct parport *p = &tmp;
 238 
 239         priv = kzalloc (sizeof (struct parport_gsc_private), GFP_KERNEL);
 240         if (!priv) {
 241                 printk (KERN_DEBUG "parport (0x%lx): no memory!\n", base);
 242                 return NULL;
 243         }
 244         ops = kmemdup(&parport_gsc_ops, sizeof(struct parport_operations),
 245                       GFP_KERNEL);
 246         if (!ops) {
 247                 printk (KERN_DEBUG "parport (0x%lx): no memory for ops!\n",
 248                         base);
 249                 kfree (priv);
 250                 return NULL;
 251         }
 252         priv->ctr = 0xc;
 253         priv->ctr_writable = 0xff;
 254         priv->dma_buf = NULL;
 255         priv->dma_handle = 0;
 256         p->base = base;
 257         p->base_hi = base_hi;
 258         p->irq = irq;
 259         p->dma = dma;
 260         p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT;
 261         p->ops = ops;
 262         p->private_data = priv;
 263         p->physport = p;
 264         if (!parport_SPP_supported (p)) {
 265                 /* No port. */
 266                 kfree (priv);
 267                 kfree(ops);
 268                 return NULL;
 269         }
 270         parport_PS2_supported (p);
 271 
 272         if (!(p = parport_register_port(base, PARPORT_IRQ_NONE,
 273                                         PARPORT_DMA_NONE, ops))) {
 274                 kfree (priv);
 275                 kfree (ops);
 276                 return NULL;
 277         }
 278 
 279         p->dev = &padev->dev;
 280         p->base_hi = base_hi;
 281         p->modes = tmp.modes;
 282         p->size = (p->modes & PARPORT_MODE_EPP)?8:3;
 283         p->private_data = priv;
 284 
 285         printk(KERN_INFO "%s: PC-style at 0x%lx", p->name, p->base);
 286         p->irq = irq;
 287         if (p->irq == PARPORT_IRQ_AUTO) {
 288                 p->irq = PARPORT_IRQ_NONE;
 289         }
 290         if (p->irq != PARPORT_IRQ_NONE) {
 291                 pr_cont(", irq %d", p->irq);
 292 
 293                 if (p->dma == PARPORT_DMA_AUTO) {
 294                         p->dma = PARPORT_DMA_NONE;
 295                 }
 296         }
 297         if (p->dma == PARPORT_DMA_AUTO) /* To use DMA, giving the irq
 298                                            is mandatory (see above) */
 299                 p->dma = PARPORT_DMA_NONE;
 300 
 301         pr_cont(" [");
 302 #define printmode(x) {if(p->modes&PARPORT_MODE_##x){pr_cont("%s%s",f?",":"",#x);f++;}}
 303         {
 304                 int f = 0;
 305                 printmode(PCSPP);
 306                 printmode(TRISTATE);
 307                 printmode(COMPAT)
 308                 printmode(EPP);
 309 //              printmode(ECP);
 310 //              printmode(DMA);
 311         }
 312 #undef printmode
 313         pr_cont("]\n");
 314 
 315         if (p->irq != PARPORT_IRQ_NONE) {
 316                 if (request_irq (p->irq, parport_irq_handler,
 317                                  0, p->name, p)) {
 318                         printk (KERN_WARNING "%s: irq %d in use, "
 319                                 "resorting to polled operation\n",
 320                                 p->name, p->irq);
 321                         p->irq = PARPORT_IRQ_NONE;
 322                         p->dma = PARPORT_DMA_NONE;
 323                 }
 324         }
 325 
 326         /* Done probing.  Now put the port into a sensible start-up state. */
 327 
 328         parport_gsc_write_data(p, 0);
 329         parport_gsc_data_forward (p);
 330 
 331         /* Now that we've told the sharing engine about the port, and
 332            found out its characteristics, let the high-level drivers
 333            know about it. */
 334         parport_announce_port (p);
 335 
 336         return p;
 337 }
 338 
 339 
 340 #define PARPORT_GSC_OFFSET 0x800
 341 
 342 static int parport_count;
 343 
 344 static int __init parport_init_chip(struct parisc_device *dev)
 345 {
 346         struct parport *p;
 347         unsigned long port;
 348 
 349         if (!dev->irq) {
 350                 printk(KERN_WARNING "IRQ not found for parallel device at 0x%llx\n",
 351                         (unsigned long long)dev->hpa.start);
 352                 return -ENODEV;
 353         }
 354 
 355         port = dev->hpa.start + PARPORT_GSC_OFFSET;
 356         
 357         /* some older machines with ASP-chip don't support
 358          * the enhanced parport modes.
 359          */
 360         if (boot_cpu_data.cpu_type > pcxt && !pdc_add_valid(port+4)) {
 361 
 362                 /* Initialize bidirectional-mode (0x10) & data-tranfer-mode #1 (0x20) */
 363                 printk("%s: initialize bidirectional-mode.\n", __func__);
 364                 parport_writeb ( (0x10 + 0x20), port + 4);
 365 
 366         } else {
 367                 printk("%s: enhanced parport-modes not supported.\n", __func__);
 368         }
 369         
 370         p = parport_gsc_probe_port(port, 0, dev->irq,
 371                         /* PARPORT_IRQ_NONE */ PARPORT_DMA_NONE, dev);
 372         if (p)
 373                 parport_count++;
 374         dev_set_drvdata(&dev->dev, p);
 375 
 376         return 0;
 377 }
 378 
 379 static int __exit parport_remove_chip(struct parisc_device *dev)
 380 {
 381         struct parport *p = dev_get_drvdata(&dev->dev);
 382         if (p) {
 383                 struct parport_gsc_private *priv = p->private_data;
 384                 struct parport_operations *ops = p->ops;
 385                 parport_remove_port(p);
 386                 if (p->dma != PARPORT_DMA_NONE)
 387                         free_dma(p->dma);
 388                 if (p->irq != PARPORT_IRQ_NONE)
 389                         free_irq(p->irq, p);
 390                 if (priv->dma_buf)
 391                         pci_free_consistent(priv->dev, PAGE_SIZE,
 392                                             priv->dma_buf,
 393                                             priv->dma_handle);
 394                 kfree (p->private_data);
 395                 parport_put_port(p);
 396                 kfree (ops); /* hope no-one cached it */
 397         }
 398         return 0;
 399 }
 400 
 401 static const struct parisc_device_id parport_tbl[] __initconst = {
 402         { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x74 },
 403         { 0, }
 404 };
 405 
 406 MODULE_DEVICE_TABLE(parisc, parport_tbl);
 407 
 408 static struct parisc_driver parport_driver __refdata = {
 409         .name           = "Parallel",
 410         .id_table       = parport_tbl,
 411         .probe          = parport_init_chip,
 412         .remove         = __exit_p(parport_remove_chip),
 413 };
 414 
 415 int parport_gsc_init(void)
 416 {
 417         return register_parisc_driver(&parport_driver);
 418 }
 419 
 420 static void parport_gsc_exit(void)
 421 {
 422         unregister_parisc_driver(&parport_driver);
 423 }
 424 
 425 module_init(parport_gsc_init);
 426 module_exit(parport_gsc_exit);
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/parport/parport_gsc.c

DEFINITIONS
