drivers/vlynq/vlynq.c

   1 /*
   2  * Copyright (C) 2006, 2007 Eugene Konev <ejka@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  *
  18  * Parts of the VLYNQ specification can be found here:
  19  * http://www.ti.com/litv/pdf/sprue36a
  20  */
  21
  22 #include <linux/init.h>
  23 #include <linux/types.h>
  24 #include <linux/kernel.h>
  25 #include <linux/string.h>
  26 #include <linux/device.h>
  27 #include <linux/module.h>
  28 #include <linux/errno.h>
  29 #include <linux/platform_device.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/device.h>
  32 #include <linux/delay.h>
  33 #include <linux/io.h>
  34
  35 #include <linux/vlynq.h>
  36
  37 #define VLYNQ_CTRL_PM_ENABLE            0x80000000
  38 #define VLYNQ_CTRL_CLOCK_INT            0x00008000
  39 #define VLYNQ_CTRL_CLOCK_DIV(x)         (((x) & 7) << 16)
  40 #define VLYNQ_CTRL_INT_LOCAL            0x00004000
  41 #define VLYNQ_CTRL_INT_ENABLE           0x00002000
  42 #define VLYNQ_CTRL_INT_VECTOR(x)        (((x) & 0x1f) << 8)
  43 #define VLYNQ_CTRL_INT2CFG              0x00000080
  44 #define VLYNQ_CTRL_RESET                0x00000001
  45
  46 #define VLYNQ_CTRL_CLOCK_MASK          (0x7 << 16)
  47
  48 #define VLYNQ_INT_OFFSET                0x00000014
  49 #define VLYNQ_REMOTE_OFFSET             0x00000080
  50
  51 #define VLYNQ_STATUS_LINK               0x00000001
  52 #define VLYNQ_STATUS_LERROR             0x00000080
  53 #define VLYNQ_STATUS_RERROR             0x00000100
  54
  55 #define VINT_ENABLE                     0x00000100
  56 #define VINT_TYPE_EDGE                  0x00000080
  57 #define VINT_LEVEL_LOW                  0x00000040
  58 #define VINT_VECTOR(x)                  ((x) & 0x1f)
  59 #define VINT_OFFSET(irq)                (8 * ((irq) % 4))
  60
  61 #define VLYNQ_AUTONEGO_V2               0x00010000
  62
  63 struct vlynq_regs {
  64         u32 revision;
  65         u32 control;
  66         u32 status;
  67         u32 int_prio;
  68         u32 int_status;
  69         u32 int_pending;
  70         u32 int_ptr;
  71         u32 tx_offset;
  72         struct vlynq_mapping rx_mapping[4];
  73         u32 chip;
  74         u32 autonego;
  75         u32 unused[6];
  76         u32 int_device[8];
  77 };
  78
  79 #ifdef CONFIG_VLYNQ_DEBUG
  80 static void vlynq_dump_regs(struct vlynq_device *dev)
  81 {
  82         int i;
  83
  84         printk(KERN_DEBUG "VLYNQ local=%p remote=%p\n",
  85                         dev->local, dev->remote);
  86         for (i = 0; i < 32; i++) {
  87                 printk(KERN_DEBUG "VLYNQ: local %d: %08x\n",
  88                         i + 1, ((u32 *)dev->local)[i]);
  89                 printk(KERN_DEBUG "VLYNQ: remote %d: %08x\n",
  90                         i + 1, ((u32 *)dev->remote)[i]);
  91         }
  92 }
  93
  94 static void vlynq_dump_mem(u32 *base, int count)
  95 {
  96         int i;
  97
  98         for (i = 0; i < (count + 3) / 4; i++) {
  99                 if (i % 4 == 0)
 100                         printk(KERN_DEBUG "\nMEM[0x%04x]:", i * 4);
 101                 printk(KERN_DEBUG " 0x%08x", *(base + i));
 102         }
 103         printk(KERN_DEBUG "\n");
 104 }
 105 #endif
 106
 107 /* Check the VLYNQ link status with a given device */
 108 static int vlynq_linked(struct vlynq_device *dev)
 109 {
 110         int i;
 111
 112         for (i = 0; i < 100; i++)
 113                 if (readl(&dev->local->status) & VLYNQ_STATUS_LINK)
 114                         return 1;
 115                 else
 116                         cpu_relax();
 117
 118         return 0;
 119 }
 120
 121 static void vlynq_reset(struct vlynq_device *dev)
 122 {
 123         writel(readl(&dev->local->control) | VLYNQ_CTRL_RESET,
 124                         &dev->local->control);
 125
 126         /* Wait for the devices to finish resetting */
 127         msleep(5);
 128
 129         /* Remove reset bit */
 130         writel(readl(&dev->local->control) & ~VLYNQ_CTRL_RESET,
 131                         &dev->local->control);
 132
 133         /* Give some time for the devices to settle */
 134         msleep(5);
 135 }
 136
 137 static void vlynq_irq_unmask(unsigned int irq)
 138 {
 139         u32 val;
 140         struct vlynq_device *dev = get_irq_chip_data(irq);
 141         int virq;
 142
 143         BUG_ON(!dev);
 144         virq = irq - dev->irq_start;
 145         val = readl(&dev->remote->int_device[virq >> 2]);
 146         val |= (VINT_ENABLE | virq) << VINT_OFFSET(virq);
 147         writel(val, &dev->remote->int_device[virq >> 2]);
 148 }
 149
 150 static void vlynq_irq_mask(unsigned int irq)
 151 {
 152         u32 val;
 153         struct vlynq_device *dev = get_irq_chip_data(irq);
 154         int virq;
 155
 156         BUG_ON(!dev);
 157         virq = irq - dev->irq_start;
 158         val = readl(&dev->remote->int_device[virq >> 2]);
 159         val &= ~(VINT_ENABLE << VINT_OFFSET(virq));
 160         writel(val, &dev->remote->int_device[virq >> 2]);
 161 }
 162
 163 static int vlynq_irq_type(unsigned int irq, unsigned int flow_type)
 164 {
 165         u32 val;
 166         struct vlynq_device *dev = get_irq_chip_data(irq);
 167         int virq;
 168
 169         BUG_ON(!dev);
 170         virq = irq - dev->irq_start;
 171         val = readl(&dev->remote->int_device[virq >> 2]);
 172         switch (flow_type & IRQ_TYPE_SENSE_MASK) {
 173         case IRQ_TYPE_EDGE_RISING:
 174         case IRQ_TYPE_EDGE_FALLING:
 175         case IRQ_TYPE_EDGE_BOTH:
 176                 val |= VINT_TYPE_EDGE << VINT_OFFSET(virq);
 177                 val &= ~(VINT_LEVEL_LOW << VINT_OFFSET(virq));
 178                 break;
 179         case IRQ_TYPE_LEVEL_HIGH:
 180                 val &= ~(VINT_TYPE_EDGE << VINT_OFFSET(virq));
 181                 val &= ~(VINT_LEVEL_LOW << VINT_OFFSET(virq));
 182                 break;
 183         case IRQ_TYPE_LEVEL_LOW:
 184                 val &= ~(VINT_TYPE_EDGE << VINT_OFFSET(virq));
 185                 val |= VINT_LEVEL_LOW << VINT_OFFSET(virq);
 186                 break;
 187         default:
 188                 return -EINVAL;
 189         }
 190         writel(val, &dev->remote->int_device[virq >> 2]);
 191         return 0;
 192 }
 193
 194 static void vlynq_local_ack(unsigned int irq)
 195 {
 196         struct vlynq_device *dev = get_irq_chip_data(irq);
 197
 198         u32 status = readl(&dev->local->status);
 199
 200         pr_debug("%s: local status: 0x%08x\n",
 201                        dev_name(&dev->dev), status);
 202         writel(status, &dev->local->status);
 203 }
 204
 205 static void vlynq_remote_ack(unsigned int irq)
 206 {
 207         struct vlynq_device *dev = get_irq_chip_data(irq);
 208
 209         u32 status = readl(&dev->remote->status);
 210
 211         pr_debug("%s: remote status: 0x%08x\n",
 212                        dev_name(&dev->dev), status);
 213         writel(status, &dev->remote->status);
 214 }
 215
 216 static irqreturn_t vlynq_irq(int irq, void *dev_id)
 217 {
 218         struct vlynq_device *dev = dev_id;
 219         u32 status;
 220         int virq = 0;
 221
 222         status = readl(&dev->local->int_status);
 223         writel(status, &dev->local->int_status);
 224
 225         if (unlikely(!status))
 226                 spurious_interrupt();
 227
 228         while (status) {
 229                 if (status & 1)
 230                         do_IRQ(dev->irq_start + virq);
 231                 status >>= 1;
 232                 virq++;
 233         }
 234
 235         return IRQ_HANDLED;
 236 }
 237
 238 static struct irq_chip vlynq_irq_chip = {
 239         .name = "vlynq",
 240         .unmask = vlynq_irq_unmask,
 241         .mask = vlynq_irq_mask,
 242         .set_type = vlynq_irq_type,
 243 };
 244
 245 static struct irq_chip vlynq_local_chip = {
 246         .name = "vlynq local error",
 247         .unmask = vlynq_irq_unmask,
 248         .mask = vlynq_irq_mask,
 249         .ack = vlynq_local_ack,
 250 };
 251
 252 static struct irq_chip vlynq_remote_chip = {
 253         .name = "vlynq local error",
 254         .unmask = vlynq_irq_unmask,
 255         .mask = vlynq_irq_mask,
 256         .ack = vlynq_remote_ack,
 257 };
 258
 259 static int vlynq_setup_irq(struct vlynq_device *dev)
 260 {
 261         u32 val;
 262         int i, virq;
 263
 264         if (dev->local_irq == dev->remote_irq) {
 265                 printk(KERN_ERR
 266                        "%s: local vlynq irq should be different from remote\n",
 267                        dev_name(&dev->dev));
 268                 return -EINVAL;
 269         }
 270
 271         /* Clear local and remote error bits */
 272         writel(readl(&dev->local->status), &dev->local->status);
 273         writel(readl(&dev->remote->status), &dev->remote->status);
 274
 275         /* Now setup interrupts */
 276         val = VLYNQ_CTRL_INT_VECTOR(dev->local_irq);
 277         val |= VLYNQ_CTRL_INT_ENABLE | VLYNQ_CTRL_INT_LOCAL |
 278                 VLYNQ_CTRL_INT2CFG;
 279         val |= readl(&dev->local->control);
 280         writel(VLYNQ_INT_OFFSET, &dev->local->int_ptr);
 281         writel(val, &dev->local->control);
 282
 283         val = VLYNQ_CTRL_INT_VECTOR(dev->remote_irq);
 284         val |= VLYNQ_CTRL_INT_ENABLE;
 285         val |= readl(&dev->remote->control);
 286         writel(VLYNQ_INT_OFFSET, &dev->remote->int_ptr);
 287         writel(val, &dev->remote->int_ptr);
 288         writel(val, &dev->remote->control);
 289
 290         for (i = dev->irq_start; i <= dev->irq_end; i++) {
 291                 virq = i - dev->irq_start;
 292                 if (virq == dev->local_irq) {
 293                         set_irq_chip_and_handler(i, &vlynq_local_chip,
 294                                                  handle_level_irq);
 295                         set_irq_chip_data(i, dev);
 296                 } else if (virq == dev->remote_irq) {
 297                         set_irq_chip_and_handler(i, &vlynq_remote_chip,
 298                                                  handle_level_irq);
 299                         set_irq_chip_data(i, dev);
 300                 } else {
 301                         set_irq_chip_and_handler(i, &vlynq_irq_chip,
 302                                                  handle_simple_irq);
 303                         set_irq_chip_data(i, dev);
 304                         writel(0, &dev->remote->int_device[virq >> 2]);
 305                 }
 306         }
 307
 308         if (request_irq(dev->irq, vlynq_irq, IRQF_SHARED, "vlynq", dev)) {
 309                 printk(KERN_ERR "%s: request_irq failed\n",
 310                                         dev_name(&dev->dev));
 311                 return -EAGAIN;
 312         }
 313
 314         return 0;
 315 }
 316
 317 static void vlynq_device_release(struct device *dev)
 318 {
 319         struct vlynq_device *vdev = to_vlynq_device(dev);
 320         kfree(vdev);
 321 }
 322
 323 static int vlynq_device_match(struct device *dev,
 324                               struct device_driver *drv)
 325 {
 326         struct vlynq_device *vdev = to_vlynq_device(dev);
 327         struct vlynq_driver *vdrv = to_vlynq_driver(drv);
 328         struct vlynq_device_id *ids = vdrv->id_table;
 329
 330         while (ids->id) {
 331                 if (ids->id == vdev->dev_id) {
 332                         vdev->divisor = ids->divisor;
 333                         vlynq_set_drvdata(vdev, ids);
 334                         printk(KERN_INFO "Driver found for VLYNQ "
 335                                 "device: %08x\n", vdev->dev_id);
 336                         return 1;
 337                 }
 338                 printk(KERN_DEBUG "Not using the %08x VLYNQ device's driver"
 339                         " for VLYNQ device: %08x\n", ids->id, vdev->dev_id);
 340                 ids++;
 341         }
 342         return 0;
 343 }
 344
 345 static int vlynq_device_probe(struct device *dev)
 346 {
 347         struct vlynq_device *vdev = to_vlynq_device(dev);
 348         struct vlynq_driver *drv = to_vlynq_driver(dev->driver);
 349         struct vlynq_device_id *id = vlynq_get_drvdata(vdev);
 350         int result = -ENODEV;
 351
 352         if (drv->probe)
 353                 result = drv->probe(vdev, id);
 354         if (result)
 355                 put_device(dev);
 356         return result;
 357 }
 358
 359 static int vlynq_device_remove(struct device *dev)
 360 {
 361         struct vlynq_driver *drv = to_vlynq_driver(dev->driver);
 362
 363         if (drv->remove)
 364                 drv->remove(to_vlynq_device(dev));
 365
 366         return 0;
 367 }
 368
 369 int __vlynq_register_driver(struct vlynq_driver *driver, struct module *owner)
 370 {
 371         driver->driver.name = driver->name;
 372         driver->driver.bus = &vlynq_bus_type;
 373         return driver_register(&driver->driver);
 374 }
 375 EXPORT_SYMBOL(__vlynq_register_driver);
 376
 377 void vlynq_unregister_driver(struct vlynq_driver *driver)
 378 {
 379         driver_unregister(&driver->driver);
 380 }
 381 EXPORT_SYMBOL(vlynq_unregister_driver);
 382
 383 /*
 384  * A VLYNQ remote device can clock the VLYNQ bus master
 385  * using a dedicated clock line. In that case, both the
 386  * remove device and the bus master should have the same
 387  * serial clock dividers configured. Iterate through the
 388  * 8 possible dividers until we actually link with the
 389  * device.
 390  */
 391 static int __vlynq_try_remote(struct vlynq_device *dev)
 392 {
 393         int i;
 394
 395         vlynq_reset(dev);
 396         for (i = dev->dev_id ? vlynq_rdiv2 : vlynq_rdiv8; dev->dev_id ?
 397                         i <= vlynq_rdiv8 : i >= vlynq_rdiv2;
 398                 dev->dev_id ? i++ : i--) {
 399
 400                 if (!vlynq_linked(dev))
 401                         break;
 402
 403                 writel((readl(&dev->remote->control) &
 404                                 ~VLYNQ_CTRL_CLOCK_MASK) |
 405                                 VLYNQ_CTRL_CLOCK_INT |
 406                                 VLYNQ_CTRL_CLOCK_DIV(i - vlynq_rdiv1),
 407                                 &dev->remote->control);
 408                 writel((readl(&dev->local->control)
 409                                 & ~(VLYNQ_CTRL_CLOCK_INT |
 410                                 VLYNQ_CTRL_CLOCK_MASK)) |
 411                                 VLYNQ_CTRL_CLOCK_DIV(i - vlynq_rdiv1),
 412                                 &dev->local->control);
 413
 414                 if (vlynq_linked(dev)) {
 415                         printk(KERN_DEBUG
 416                                 "%s: using remote clock divisor %d\n",
 417                                 dev_name(&dev->dev), i - vlynq_rdiv1 + 1);
 418                         dev->divisor = i;
 419                         return 0;
 420                 } else {
 421                         vlynq_reset(dev);
 422                 }
 423         }
 424
 425         return -ENODEV;
 426 }
 427
 428 /*
 429  * A VLYNQ remote device can be clocked by the VLYNQ bus
 430  * master using a dedicated clock line. In that case, only
 431  * the bus master configures the serial clock divider.
 432  * Iterate through the 8 possible dividers until we
 433  * actually get a link with the device.
 434  */
 435 static int __vlynq_try_local(struct vlynq_device *dev)
 436 {
 437         int i;
 438
 439         vlynq_reset(dev);
 440
 441         for (i = dev->dev_id ? vlynq_ldiv2 : vlynq_ldiv8; dev->dev_id ?
 442                         i <= vlynq_ldiv8 : i >= vlynq_ldiv2;
 443                 dev->dev_id ? i++ : i--) {
 444
 445                 writel((readl(&dev->local->control) &
 446                                 ~VLYNQ_CTRL_CLOCK_MASK) |
 447                                 VLYNQ_CTRL_CLOCK_INT |
 448                                 VLYNQ_CTRL_CLOCK_DIV(i - vlynq_ldiv1),
 449                                 &dev->local->control);
 450
 451                 if (vlynq_linked(dev)) {
 452                         printk(KERN_DEBUG
 453                                 "%s: using local clock divisor %d\n",
 454                                 dev_name(&dev->dev), i - vlynq_ldiv1 + 1);
 455                         dev->divisor = i;
 456                         return 0;
 457                 } else {
 458                         vlynq_reset(dev);
 459                 }
 460         }
 461
 462         return -ENODEV;
 463 }
 464
 465 /*
 466  * When using external clocking method, serial clock
 467  * is supplied by an external oscillator, therefore we
 468  * should mask the local clock bit in the clock control
 469  * register for both the bus master and the remote device.
 470  */
 471 static int __vlynq_try_external(struct vlynq_device *dev)
 472 {
 473         vlynq_reset(dev);
 474         if (!vlynq_linked(dev))
 475                 return -ENODEV;
 476
 477         writel((readl(&dev->remote->control) &
 478                         ~VLYNQ_CTRL_CLOCK_INT),
 479                         &dev->remote->control);
 480
 481         writel((readl(&dev->local->control) &
 482                         ~VLYNQ_CTRL_CLOCK_INT),
 483                         &dev->local->control);
 484
 485         if (vlynq_linked(dev)) {
 486                 printk(KERN_DEBUG "%s: using external clock\n",
 487                         dev_name(&dev->dev));
 488                         dev->divisor = vlynq_div_external;
 489                 return 0;
 490         }
 491
 492         return -ENODEV;
 493 }
 494
 495 static int __vlynq_enable_device(struct vlynq_device *dev)
 496 {
 497         int result;
 498         struct plat_vlynq_ops *ops = dev->dev.platform_data;
 499
 500         result = ops->on(dev);
 501         if (result)
 502                 return result;
 503
 504         switch (dev->divisor) {
 505         case vlynq_div_external:
 506         case vlynq_div_auto:
 507                 /* When the device is brought from reset it should have clock
 508                  * generation negotiated by hardware.
 509                  * Check which device is generating clocks and perform setup
 510                  * accordingly */
 511                 if (vlynq_linked(dev) && readl(&dev->remote->control) &
 512                    VLYNQ_CTRL_CLOCK_INT) {
 513                         if (!__vlynq_try_remote(dev) ||
 514                                 !__vlynq_try_local(dev)  ||
 515                                 !__vlynq_try_external(dev))
 516                                 return 0;
 517                 } else {
 518                         if (!__vlynq_try_external(dev) ||
 519                                 !__vlynq_try_local(dev)    ||
 520                                 !__vlynq_try_remote(dev))
 521                                 return 0;
 522                 }
 523                 break;
 524         case vlynq_ldiv1:
 525         case vlynq_ldiv2:
 526         case vlynq_ldiv3:
 527         case vlynq_ldiv4:
 528         case vlynq_ldiv5:
 529         case vlynq_ldiv6:
 530         case vlynq_ldiv7:
 531         case vlynq_ldiv8:
 532                 writel(VLYNQ_CTRL_CLOCK_INT |
 533                         VLYNQ_CTRL_CLOCK_DIV(dev->divisor -
 534                         vlynq_ldiv1), &dev->local->control);
 535                 writel(0, &dev->remote->control);
 536                 if (vlynq_linked(dev)) {
 537                         printk(KERN_DEBUG
 538                                 "%s: using local clock divisor %d\n",
 539                                 dev_name(&dev->dev),
 540                                 dev->divisor - vlynq_ldiv1 + 1);
 541                         return 0;
 542                 }
 543                 break;
 544         case vlynq_rdiv1:
 545         case vlynq_rdiv2:
 546         case vlynq_rdiv3:
 547         case vlynq_rdiv4:
 548         case vlynq_rdiv5:
 549         case vlynq_rdiv6:
 550         case vlynq_rdiv7:
 551         case vlynq_rdiv8:
 552                 writel(0, &dev->local->control);
 553                 writel(VLYNQ_CTRL_CLOCK_INT |
 554                         VLYNQ_CTRL_CLOCK_DIV(dev->divisor -
 555                         vlynq_rdiv1), &dev->remote->control);
 556                 if (vlynq_linked(dev)) {
 557                         printk(KERN_DEBUG
 558                                 "%s: using remote clock divisor %d\n",
 559                                 dev_name(&dev->dev),
 560                                 dev->divisor - vlynq_rdiv1 + 1);
 561                         return 0;
 562                 }
 563                 break;
 564         }
 565
 566         ops->off(dev);
 567         return -ENODEV;
 568 }
 569
 570 int vlynq_enable_device(struct vlynq_device *dev)
 571 {
 572         struct plat_vlynq_ops *ops = dev->dev.platform_data;
 573         int result = -ENODEV;
 574
 575         result = __vlynq_enable_device(dev);
 576         if (result)
 577                 return result;
 578
 579         result = vlynq_setup_irq(dev);
 580         if (result)
 581                 ops->off(dev);
 582
 583         dev->enabled = !result;
 584         return result;
 585 }
 586 EXPORT_SYMBOL(vlynq_enable_device);
 587
 588
 589 void vlynq_disable_device(struct vlynq_device *dev)
 590 {
 591         struct plat_vlynq_ops *ops = dev->dev.platform_data;
 592
 593         dev->enabled = 0;
 594         free_irq(dev->irq, dev);
 595         ops->off(dev);
 596 }
 597 EXPORT_SYMBOL(vlynq_disable_device);
 598
 599 int vlynq_set_local_mapping(struct vlynq_device *dev, u32 tx_offset,
 600                             struct vlynq_mapping *mapping)
 601 {
 602         int i;
 603
 604         if (!dev->enabled)
 605                 return -ENXIO;
 606
 607         writel(tx_offset, &dev->local->tx_offset);
 608         for (i = 0; i < 4; i++) {
 609                 writel(mapping[i].offset, &dev->local->rx_mapping[i].offset);
 610                 writel(mapping[i].size, &dev->local->rx_mapping[i].size);
 611         }
 612         return 0;
 613 }
 614 EXPORT_SYMBOL(vlynq_set_local_mapping);
 615
 616 int vlynq_set_remote_mapping(struct vlynq_device *dev, u32 tx_offset,
 617                              struct vlynq_mapping *mapping)
 618 {
 619         int i;
 620
 621         if (!dev->enabled)
 622                 return -ENXIO;
 623
 624         writel(tx_offset, &dev->remote->tx_offset);
 625         for (i = 0; i < 4; i++) {
 626                 writel(mapping[i].offset, &dev->remote->rx_mapping[i].offset);
 627                 writel(mapping[i].size, &dev->remote->rx_mapping[i].size);
 628         }
 629         return 0;
 630 }
 631 EXPORT_SYMBOL(vlynq_set_remote_mapping);
 632
 633 int vlynq_set_local_irq(struct vlynq_device *dev, int virq)
 634 {
 635         int irq = dev->irq_start + virq;
 636         if (dev->enabled)
 637                 return -EBUSY;
 638
 639         if ((irq < dev->irq_start) || (irq > dev->irq_end))
 640                 return -EINVAL;
 641
 642         if (virq == dev->remote_irq)
 643                 return -EINVAL;
 644
 645         dev->local_irq = virq;
 646
 647         return 0;
 648 }
 649 EXPORT_SYMBOL(vlynq_set_local_irq);
 650
 651 int vlynq_set_remote_irq(struct vlynq_device *dev, int virq)
 652 {
 653         int irq = dev->irq_start + virq;
 654         if (dev->enabled)
 655                 return -EBUSY;
 656
 657         if ((irq < dev->irq_start) || (irq > dev->irq_end))
 658                 return -EINVAL;
 659
 660         if (virq == dev->local_irq)
 661                 return -EINVAL;
 662
 663         dev->remote_irq = virq;
 664
 665         return 0;
 666 }
 667 EXPORT_SYMBOL(vlynq_set_remote_irq);
 668
 669 static int vlynq_probe(struct platform_device *pdev)
 670 {
 671         struct vlynq_device *dev;
 672         struct resource *regs_res, *mem_res, *irq_res;
 673         int len, result;
 674
 675         regs_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
 676         if (!regs_res)
 677                 return -ENODEV;
 678
 679         mem_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem");
 680         if (!mem_res)
 681                 return -ENODEV;
 682
 683         irq_res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "devirq");
 684         if (!irq_res)
 685                 return -ENODEV;
 686
 687         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 688         if (!dev) {
 689                 printk(KERN_ERR
 690                        "vlynq: failed to allocate device structure\n");
 691                 return -ENOMEM;
 692         }
 693
 694         dev->id = pdev->id;
 695         dev->dev.bus = &vlynq_bus_type;
 696         dev->dev.parent = &pdev->dev;
 697         dev_set_name(&dev->dev, "vlynq%d", dev->id);
 698         dev->dev.platform_data = pdev->dev.platform_data;
 699         dev->dev.release = vlynq_device_release;
 700
 701         dev->regs_start = regs_res->start;
 702         dev->regs_end = regs_res->end;
 703         dev->mem_start = mem_res->start;
 704         dev->mem_end = mem_res->end;
 705
 706         len = regs_res->end - regs_res->start;
 707         if (!request_mem_region(regs_res->start, len, dev_name(&dev->dev))) {
 708                 printk(KERN_ERR "%s: Can't request vlynq registers\n",
 709                        dev_name(&dev->dev));
 710                 result = -ENXIO;
 711                 goto fail_request;
 712         }
 713
 714         dev->local = ioremap(regs_res->start, len);
 715         if (!dev->local) {
 716                 printk(KERN_ERR "%s: Can't remap vlynq registers\n",
 717                        dev_name(&dev->dev));
 718                 result = -ENXIO;
 719                 goto fail_remap;
 720         }
 721
 722         dev->remote = (struct vlynq_regs *)((void *)dev->local +
 723                                             VLYNQ_REMOTE_OFFSET);
 724
 725         dev->irq = platform_get_irq_byname(pdev, "irq");
 726         dev->irq_start = irq_res->start;
 727         dev->irq_end = irq_res->end;
 728         dev->local_irq = dev->irq_end - dev->irq_start;
 729         dev->remote_irq = dev->local_irq - 1;
 730
 731         if (device_register(&dev->dev))
 732                 goto fail_register;
 733         platform_set_drvdata(pdev, dev);
 734
 735         printk(KERN_INFO "%s: regs 0x%p, irq %d, mem 0x%p\n",
 736                dev_name(&dev->dev), (void *)dev->regs_start, dev->irq,
 737                (void *)dev->mem_start);
 738
 739         dev->dev_id = 0;
 740         dev->divisor = vlynq_div_auto;
 741         result = __vlynq_enable_device(dev);
 742         if (result == 0) {
 743                 dev->dev_id = readl(&dev->remote->chip);
 744                 ((struct plat_vlynq_ops *)(dev->dev.platform_data))->off(dev);
 745         }
 746         if (dev->dev_id)
 747                 printk(KERN_INFO "Found a VLYNQ device: %08x\n", dev->dev_id);
 748
 749         return 0;
 750
 751 fail_register:
 752         iounmap(dev->local);
 753 fail_remap:
 754 fail_request:
 755         release_mem_region(regs_res->start, len);
 756         kfree(dev);
 757         return result;
 758 }
 759
 760 static int vlynq_remove(struct platform_device *pdev)
 761 {
 762         struct vlynq_device *dev = platform_get_drvdata(pdev);
 763
 764         device_unregister(&dev->dev);
 765         iounmap(dev->local);
 766         release_mem_region(dev->regs_start, dev->regs_end - dev->regs_start);
 767
 768         kfree(dev);
 769
 770         return 0;
 771 }
 772
 773 static struct platform_driver vlynq_platform_driver = {
 774         .driver.name = "vlynq",
 775         .probe = vlynq_probe,
 776         .remove = __devexit_p(vlynq_remove),
 777 };
 778
 779 struct bus_type vlynq_bus_type = {
 780         .name = "vlynq",
 781         .match = vlynq_device_match,
 782         .probe = vlynq_device_probe,
 783         .remove = vlynq_device_remove,
 784 };
 785 EXPORT_SYMBOL(vlynq_bus_type);
 786
 787 static int __devinit vlynq_init(void)
 788 {
 789         int res = 0;
 790
 791         res = bus_register(&vlynq_bus_type);
 792         if (res)
 793                 goto fail_bus;
 794
 795         res = platform_driver_register(&vlynq_platform_driver);
 796         if (res)
 797                 goto fail_platform;
 798
 799         return 0;
 800
 801 fail_platform:
 802         bus_unregister(&vlynq_bus_type);
 803 fail_bus:
 804         return res;
 805 }
 806
 807 static void __devexit vlynq_exit(void)
 808 {
 809         platform_driver_unregister(&vlynq_platform_driver);
 810         bus_unregister(&vlynq_bus_type);
 811 }
 812
 813 module_init(vlynq_init);
 814 module_exit(vlynq_exit);