arch/powerpc/kernel/ibmebus.c

   1 /*
   2  * IBM PowerPC IBM eBus Infrastructure Support.
   3  *
   4  * Copyright (c) 2005 IBM Corporation
   5  *  Joachim Fenkes <fenkes@de.ibm.com>
   6  *  Heiko J Schick <schickhj@de.ibm.com>
   7  *
   8  * All rights reserved.
   9  *
  10  * This source code is distributed under a dual license of GPL v2.0 and OpenIB
  11  * BSD.
  12  *
  13  * OpenIB BSD License
  14  *
  15  * Redistribution and use in source and binary forms, with or without
  16  * modification, are permitted provided that the following conditions are met:
  17  *
  18  * Redistributions of source code must retain the above copyright notice, this
  19  * list of conditions and the following disclaimer.
  20  *
  21  * Redistributions in binary form must reproduce the above copyright notice,
  22  * this list of conditions and the following disclaimer in the documentation
  23  * and/or other materials
  24  * provided with the distribution.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  27  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  30  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  33  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  34  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  36  * POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 #include <linux/init.h>
  40 #include <linux/console.h>
  41 #include <linux/kobject.h>
  42 #include <linux/dma-mapping.h>
  43 #include <linux/interrupt.h>
  44 #include <asm/ibmebus.h>
  45 #include <asm/abs_addr.h>
  46
  47 static struct device ibmebus_bus_device = { /* fake "parent" device */
  48         .bus_id = "ibmebus",
  49 };
  50
  51 struct bus_type ibmebus_bus_type;
  52
  53 static void *ibmebus_alloc_coherent(struct device *dev,
  54                                     size_t size,
  55                                     dma_addr_t *dma_handle,
  56                                     gfp_t flag)
  57 {
  58         void *mem;
  59
  60         mem = kmalloc(size, flag);
  61         *dma_handle = (dma_addr_t)mem;
  62
  63         return mem;
  64 }
  65
  66 static void ibmebus_free_coherent(struct device *dev,
  67                                   size_t size, void *vaddr,
  68                                   dma_addr_t dma_handle)
  69 {
  70         kfree(vaddr);
  71 }
  72
  73 static dma_addr_t ibmebus_map_single(struct device *dev,
  74                                      void *ptr,
  75                                      size_t size,
  76                                      enum dma_data_direction direction)
  77 {
  78         return (dma_addr_t)(ptr);
  79 }
  80
  81 static void ibmebus_unmap_single(struct device *dev,
  82                                  dma_addr_t dma_addr,
  83                                  size_t size,
  84                                  enum dma_data_direction direction)
  85 {
  86         return;
  87 }
  88
  89 static int ibmebus_map_sg(struct device *dev,
  90                           struct scatterlist *sg,
  91                           int nents, enum dma_data_direction direction)
  92 {
  93         int i;
  94
  95         for (i = 0; i < nents; i++) {
  96                 sg[i].dma_address = (dma_addr_t)page_address(sg[i].page)
  97                         + sg[i].offset;
  98                 sg[i].dma_length = sg[i].length;
  99         }
 100
 101         return nents;
 102 }
 103
 104 static void ibmebus_unmap_sg(struct device *dev,
 105                              struct scatterlist *sg,
 106                              int nents, enum dma_data_direction direction)
 107 {
 108         return;
 109 }
 110
 111 static int ibmebus_dma_supported(struct device *dev, u64 mask)
 112 {
 113         return 1;
 114 }
 115
 116 static struct dma_mapping_ops ibmebus_dma_ops = {
 117         .alloc_coherent = ibmebus_alloc_coherent,
 118         .free_coherent  = ibmebus_free_coherent,
 119         .map_single     = ibmebus_map_single,
 120         .unmap_single   = ibmebus_unmap_single,
 121         .map_sg         = ibmebus_map_sg,
 122         .unmap_sg       = ibmebus_unmap_sg,
 123         .dma_supported  = ibmebus_dma_supported,
 124 };
 125
 126 static int ibmebus_bus_probe(struct device *dev)
 127 {
 128         struct ibmebus_dev *ibmebusdev    = to_ibmebus_dev(dev);
 129         struct ibmebus_driver *ibmebusdrv = to_ibmebus_driver(dev->driver);
 130         const struct of_device_id *id;
 131         int error = -ENODEV;
 132
 133         if (!ibmebusdrv->probe)
 134                 return error;
 135
 136         id = of_match_device(ibmebusdrv->id_table, &ibmebusdev->ofdev);
 137         if (id) {
 138                 error = ibmebusdrv->probe(ibmebusdev, id);
 139         }
 140
 141         return error;
 142 }
 143
 144 static int ibmebus_bus_remove(struct device *dev)
 145 {
 146         struct ibmebus_dev *ibmebusdev    = to_ibmebus_dev(dev);
 147         struct ibmebus_driver *ibmebusdrv = to_ibmebus_driver(dev->driver);
 148
 149         if (ibmebusdrv->remove) {
 150                 return ibmebusdrv->remove(ibmebusdev);
 151         }
 152
 153         return 0;
 154 }
 155
 156 static void __devinit ibmebus_dev_release(struct device *dev)
 157 {
 158         of_node_put(to_ibmebus_dev(dev)->ofdev.node);
 159         kfree(to_ibmebus_dev(dev));
 160 }
 161
 162 static int __devinit ibmebus_register_device_common(
 163         struct ibmebus_dev *dev, const char *name)
 164 {
 165         int err = 0;
 166
 167         dev->ofdev.dev.parent  = &ibmebus_bus_device;
 168         dev->ofdev.dev.bus     = &ibmebus_bus_type;
 169         dev->ofdev.dev.release = ibmebus_dev_release;
 170
 171         dev->ofdev.dev.archdata.of_node = dev->ofdev.node;
 172         dev->ofdev.dev.archdata.dma_ops = &ibmebus_dma_ops;
 173         dev->ofdev.dev.archdata.numa_node = of_node_to_nid(dev->ofdev.node);
 174
 175         /* An ibmebusdev is based on a of_device. We have to change the
 176          * bus type to use our own DMA mapping operations.
 177          */
 178         if ((err = of_device_register(&dev->ofdev)) != 0) {
 179                 printk(KERN_ERR "%s: failed to register device (%d).\n",
 180                        __FUNCTION__, err);
 181                 return -ENODEV;
 182         }
 183
 184         return 0;
 185 }
 186
 187 static struct ibmebus_dev* __devinit ibmebus_register_device_node(
 188         struct device_node *dn)
 189 {
 190         struct ibmebus_dev *dev;
 191         const char *loc_code;
 192         int length;
 193
 194         loc_code = of_get_property(dn, "ibm,loc-code", NULL);
 195         if (!loc_code) {
 196                 printk(KERN_WARNING "%s: node %s missing 'ibm,loc-code'\n",
 197                        __FUNCTION__, dn->name ? dn->name : "<unknown>");
 198                 return ERR_PTR(-EINVAL);
 199         }
 200
 201         if (strlen(loc_code) == 0) {
 202                 printk(KERN_WARNING "%s: 'ibm,loc-code' is invalid\n",
 203                        __FUNCTION__);
 204                 return ERR_PTR(-EINVAL);
 205         }
 206
 207         dev = kzalloc(sizeof(struct ibmebus_dev), GFP_KERNEL);
 208         if (!dev) {
 209                 return ERR_PTR(-ENOMEM);
 210         }
 211
 212         dev->ofdev.node = of_node_get(dn);
 213
 214         length = strlen(loc_code);
 215         memcpy(dev->ofdev.dev.bus_id, loc_code
 216                 + (length - min(length, BUS_ID_SIZE - 1)),
 217                 min(length, BUS_ID_SIZE - 1));
 218
 219         /* Register with generic device framework. */
 220         if (ibmebus_register_device_common(dev, dn->name) != 0) {
 221                 kfree(dev);
 222                 return ERR_PTR(-ENODEV);
 223         }
 224
 225         return dev;
 226 }
 227
 228 static void ibmebus_probe_of_nodes(char* name)
 229 {
 230         struct device_node *dn = NULL;
 231
 232         while ((dn = of_find_node_by_name(dn, name))) {
 233                 if (IS_ERR(ibmebus_register_device_node(dn))) {
 234                         of_node_put(dn);
 235                         return;
 236                 }
 237         }
 238
 239         of_node_put(dn);
 240
 241         return;
 242 }
 243
 244 static void ibmebus_add_devices_by_id(struct of_device_id *idt)
 245 {
 246         while (strlen(idt->name) > 0) {
 247                 ibmebus_probe_of_nodes(idt->name);
 248                 idt++;
 249         }
 250
 251         return;
 252 }
 253
 254 static int ibmebus_match_name(struct device *dev, void *data)
 255 {
 256         const struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);
 257         const char *name;
 258
 259         name = of_get_property(ebus_dev->ofdev.node, "name", NULL);
 260
 261         if (name && (strcmp(data, name) == 0))
 262                 return 1;
 263
 264         return 0;
 265 }
 266
 267 static int ibmebus_unregister_device(struct device *dev)
 268 {
 269         of_device_unregister(to_of_device(dev));
 270
 271         return 0;
 272 }
 273
 274 static void ibmebus_remove_devices_by_id(struct of_device_id *idt)
 275 {
 276         struct device *dev;
 277
 278         while (strlen(idt->name) > 0) {
 279                 while ((dev = bus_find_device(&ibmebus_bus_type, NULL,
 280                                               (void*)idt->name,
 281                                               ibmebus_match_name))) {
 282                         ibmebus_unregister_device(dev);
 283                 }
 284                 idt++;
 285         }
 286
 287         return;
 288 }
 289
 290 int ibmebus_register_driver(struct ibmebus_driver *drv)
 291 {
 292         int err = 0;
 293
 294         drv->driver.name   = drv->name;
 295         drv->driver.bus    = &ibmebus_bus_type;
 296         drv->driver.probe  = ibmebus_bus_probe;
 297         drv->driver.remove = ibmebus_bus_remove;
 298
 299         if ((err = driver_register(&drv->driver) != 0))
 300                 return err;
 301
 302         /* remove all supported devices first, in case someone
 303          * probed them manually before registering the driver */
 304         ibmebus_remove_devices_by_id(drv->id_table);
 305         ibmebus_add_devices_by_id(drv->id_table);
 306
 307         return 0;
 308 }
 309 EXPORT_SYMBOL(ibmebus_register_driver);
 310
 311 void ibmebus_unregister_driver(struct ibmebus_driver *drv)
 312 {
 313         driver_unregister(&drv->driver);
 314         ibmebus_remove_devices_by_id(drv->id_table);
 315 }
 316 EXPORT_SYMBOL(ibmebus_unregister_driver);
 317
 318 int ibmebus_request_irq(struct ibmebus_dev *dev,
 319                         u32 ist,
 320                         irq_handler_t handler,
 321                         unsigned long irq_flags, const char * devname,
 322                         void *dev_id)
 323 {
 324         unsigned int irq = irq_create_mapping(NULL, ist);
 325
 326         if (irq == NO_IRQ)
 327                 return -EINVAL;
 328
 329         return request_irq(irq, handler,
 330                            irq_flags, devname, dev_id);
 331 }
 332 EXPORT_SYMBOL(ibmebus_request_irq);
 333
 334 void ibmebus_free_irq(struct ibmebus_dev *dev, u32 ist, void *dev_id)
 335 {
 336         unsigned int irq = irq_find_mapping(NULL, ist);
 337
 338         free_irq(irq, dev_id);
 339 }
 340 EXPORT_SYMBOL(ibmebus_free_irq);
 341
 342 static int ibmebus_bus_match(struct device *dev, struct device_driver *drv)
 343 {
 344         const struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);
 345         struct ibmebus_driver *ebus_drv    = to_ibmebus_driver(drv);
 346         const struct of_device_id *ids     = ebus_drv->id_table;
 347         const struct of_device_id *found_id;
 348
 349         if (!ids)
 350                 return 0;
 351
 352         found_id = of_match_device(ids, &ebus_dev->ofdev);
 353         if (found_id)
 354                 return 1;
 355
 356         return 0;
 357 }
 358
 359 static ssize_t name_show(struct device *dev,
 360                          struct device_attribute *attr, char *buf)
 361 {
 362         struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);
 363         const char *name = of_get_property(ebus_dev->ofdev.node, "name", NULL);
 364         return sprintf(buf, "%s\n", name);
 365 }
 366
 367 static struct device_attribute ibmebus_dev_attrs[] = {
 368         __ATTR_RO(name),
 369         __ATTR_NULL
 370 };
 371
 372 static int ibmebus_match_path(struct device *dev, void *data)
 373 {
 374         int rc;
 375         struct device_node *dn =
 376                 of_node_get(to_ibmebus_dev(dev)->ofdev.node);
 377
 378         rc = (dn->full_name && (strcasecmp((char*)data, dn->full_name) == 0));
 379
 380         of_node_put(dn);
 381         return rc;
 382 }
 383
 384 static char *ibmebus_chomp(const char *in, size_t count)
 385 {
 386         char *out = (char*)kmalloc(count + 1, GFP_KERNEL);
 387         if (!out)
 388                 return NULL;
 389
 390         memcpy(out, in, count);
 391         out[count] = '\0';
 392         if (out[count - 1] == '\n')
 393                 out[count - 1] = '\0';
 394
 395         return out;
 396 }
 397
 398 static ssize_t ibmebus_store_probe(struct bus_type *bus,
 399                                    const char *buf, size_t count)
 400 {
 401         struct device_node *dn = NULL;
 402         struct ibmebus_dev *dev;
 403         char *path;
 404         ssize_t rc;
 405
 406         path = ibmebus_chomp(buf, count);
 407         if (!path)
 408                 return -ENOMEM;
 409
 410         if (bus_find_device(&ibmebus_bus_type, NULL, path,
 411                              ibmebus_match_path)) {
 412                 printk(KERN_WARNING "%s: %s has already been probed\n",
 413                        __FUNCTION__, path);
 414                 rc = -EINVAL;
 415                 goto out;
 416         }
 417
 418         if ((dn = of_find_node_by_path(path))) {
 419                 dev = ibmebus_register_device_node(dn);
 420                 of_node_put(dn);
 421                 rc = IS_ERR(dev) ? PTR_ERR(dev) : count;
 422         } else {
 423                 printk(KERN_WARNING "%s: no such device node: %s\n",
 424                        __FUNCTION__, path);
 425                 rc = -ENODEV;
 426         }
 427
 428 out:
 429         kfree(path);
 430         return rc;
 431 }
 432
 433 static ssize_t ibmebus_store_remove(struct bus_type *bus,
 434                                     const char *buf, size_t count)
 435 {
 436         struct device *dev;
 437         char *path;
 438
 439         path = ibmebus_chomp(buf, count);
 440         if (!path)
 441                 return -ENOMEM;
 442
 443         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
 444                                    ibmebus_match_path))) {
 445                 ibmebus_unregister_device(dev);
 446
 447                 kfree(path);
 448                 return count;
 449         } else {
 450                 printk(KERN_WARNING "%s: %s not on the bus\n",
 451                        __FUNCTION__, path);
 452
 453                 kfree(path);
 454                 return -ENODEV;
 455         }
 456 }
 457
 458 static struct bus_attribute ibmebus_bus_attrs[] = {
 459         __ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe),
 460         __ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove),
 461         __ATTR_NULL
 462 };
 463
 464 struct bus_type ibmebus_bus_type = {
 465         .name      = "ibmebus",
 466         .match     = ibmebus_bus_match,
 467         .dev_attrs = ibmebus_dev_attrs,
 468         .bus_attrs = ibmebus_bus_attrs
 469 };
 470 EXPORT_SYMBOL(ibmebus_bus_type);
 471
 472 static int __init ibmebus_bus_init(void)
 473 {
 474         int err;
 475
 476         printk(KERN_INFO "IBM eBus Device Driver\n");
 477
 478         err = bus_register(&ibmebus_bus_type);
 479         if (err) {
 480                 printk(KERN_ERR ":%s: failed to register IBM eBus.\n",
 481                        __FUNCTION__);
 482                 return err;
 483         }
 484
 485         err = device_register(&ibmebus_bus_device);
 486         if (err) {
 487                 printk(KERN_WARNING "%s: device_register returned %i\n",
 488                        __FUNCTION__, err);
 489                 bus_unregister(&ibmebus_bus_type);
 490
 491                 return err;
 492         }
 493
 494         return 0;
 495 }
 496 __initcall(ibmebus_bus_init);