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 #define MAX_LOC_CODE_LENGTH 80
  48
  49 static struct device ibmebus_bus_device = { /* fake "parent" device */
  50         .bus_id = "ibmebus",
  51 };
  52
  53 struct bus_type ibmebus_bus_type;
  54
  55 static void *ibmebus_alloc_coherent(struct device *dev,
  56                                     size_t size,
  57                                     dma_addr_t *dma_handle,
  58                                     gfp_t flag)
  59 {
  60         void *mem;
  61
  62         mem = kmalloc(size, flag);
  63         *dma_handle = (dma_addr_t)mem;
  64
  65         return mem;
  66 }
  67
  68 static void ibmebus_free_coherent(struct device *dev,
  69                                   size_t size, void *vaddr,
  70                                   dma_addr_t dma_handle)
  71 {
  72         kfree(vaddr);
  73 }
  74
  75 static dma_addr_t ibmebus_map_single(struct device *dev,
  76                                      void *ptr,
  77                                      size_t size,
  78                                      enum dma_data_direction direction)
  79 {
  80         return (dma_addr_t)(ptr);
  81 }
  82
  83 static void ibmebus_unmap_single(struct device *dev,
  84                                  dma_addr_t dma_addr,
  85                                  size_t size,
  86                                  enum dma_data_direction direction)
  87 {
  88         return;
  89 }
  90
  91 static int ibmebus_map_sg(struct device *dev,
  92                           struct scatterlist *sg,
  93                           int nents, enum dma_data_direction direction)
  94 {
  95         int i;
  96
  97         for (i = 0; i < nents; i++) {
  98                 sg[i].dma_address = (dma_addr_t)page_address(sg[i].page)
  99                         + sg[i].offset;
 100                 sg[i].dma_length = sg[i].length;
 101         }
 102
 103         return nents;
 104 }
 105
 106 static void ibmebus_unmap_sg(struct device *dev,
 107                              struct scatterlist *sg,
 108                              int nents, enum dma_data_direction direction)
 109 {
 110         return;
 111 }
 112
 113 static int ibmebus_dma_supported(struct device *dev, u64 mask)
 114 {
 115         return 1;
 116 }
 117
 118 static struct dma_mapping_ops ibmebus_dma_ops = {
 119         .alloc_coherent = ibmebus_alloc_coherent,
 120         .free_coherent  = ibmebus_free_coherent,
 121         .map_single     = ibmebus_map_single,
 122         .unmap_single   = ibmebus_unmap_single,
 123         .map_sg         = ibmebus_map_sg,
 124         .unmap_sg       = ibmebus_unmap_sg,
 125         .dma_supported  = ibmebus_dma_supported,
 126 };
 127
 128 static int ibmebus_bus_probe(struct device *dev)
 129 {
 130         struct ibmebus_dev *ibmebusdev    = to_ibmebus_dev(dev);
 131         struct ibmebus_driver *ibmebusdrv = to_ibmebus_driver(dev->driver);
 132         const struct of_device_id *id;
 133         int error = -ENODEV;
 134
 135         if (!ibmebusdrv->probe)
 136                 return error;
 137
 138         id = of_match_device(ibmebusdrv->id_table, &ibmebusdev->ofdev);
 139         if (id) {
 140                 error = ibmebusdrv->probe(ibmebusdev, id);
 141         }
 142
 143         return error;
 144 }
 145
 146 static int ibmebus_bus_remove(struct device *dev)
 147 {
 148         struct ibmebus_dev *ibmebusdev    = to_ibmebus_dev(dev);
 149         struct ibmebus_driver *ibmebusdrv = to_ibmebus_driver(dev->driver);
 150
 151         if (ibmebusdrv->remove) {
 152                 return ibmebusdrv->remove(ibmebusdev);
 153         }
 154
 155         return 0;
 156 }
 157
 158 static void __devinit ibmebus_dev_release(struct device *dev)
 159 {
 160         of_node_put(to_ibmebus_dev(dev)->ofdev.node);
 161         kfree(to_ibmebus_dev(dev));
 162 }
 163
 164 static int __devinit ibmebus_register_device_common(
 165         struct ibmebus_dev *dev, const char *name)
 166 {
 167         int err = 0;
 168
 169         dev->ofdev.dev.parent  = &ibmebus_bus_device;
 170         dev->ofdev.dev.bus     = &ibmebus_bus_type;
 171         dev->ofdev.dev.release = ibmebus_dev_release;
 172
 173         dev->ofdev.dev.archdata.of_node = dev->ofdev.node;
 174         dev->ofdev.dev.archdata.dma_ops = &ibmebus_dma_ops;
 175         dev->ofdev.dev.archdata.numa_node = of_node_to_nid(dev->ofdev.node);
 176
 177         /* An ibmebusdev is based on a of_device. We have to change the
 178          * bus type to use our own DMA mapping operations.
 179          */
 180         if ((err = of_device_register(&dev->ofdev)) != 0) {
 181                 printk(KERN_ERR "%s: failed to register device (%d).\n",
 182                        __FUNCTION__, err);
 183                 return -ENODEV;
 184         }
 185
 186         return 0;
 187 }
 188
 189 static struct ibmebus_dev* __devinit ibmebus_register_device_node(
 190         struct device_node *dn)
 191 {
 192         struct ibmebus_dev *dev;
 193         const char *loc_code;
 194         int length;
 195
 196         loc_code = get_property(dn, "ibm,loc-code", NULL);
 197         if (!loc_code) {
 198                 printk(KERN_WARNING "%s: node %s missing 'ibm,loc-code'\n",
 199                        __FUNCTION__, dn->name ? dn->name : "<unknown>");
 200                 return ERR_PTR(-EINVAL);
 201         }
 202
 203         if (strlen(loc_code) == 0) {
 204                 printk(KERN_WARNING "%s: 'ibm,loc-code' is invalid\n",
 205                        __FUNCTION__);
 206                 return ERR_PTR(-EINVAL);
 207         }
 208
 209         dev = kzalloc(sizeof(struct ibmebus_dev), GFP_KERNEL);
 210         if (!dev) {
 211                 return ERR_PTR(-ENOMEM);
 212         }
 213
 214         dev->ofdev.node = of_node_get(dn);
 215
 216         length = strlen(loc_code);
 217         memcpy(dev->ofdev.dev.bus_id, loc_code
 218                 + (length - min(length, BUS_ID_SIZE - 1)),
 219                 min(length, BUS_ID_SIZE - 1));
 220
 221         /* Register with generic device framework. */
 222         if (ibmebus_register_device_common(dev, dn->name) != 0) {
 223                 kfree(dev);
 224                 return ERR_PTR(-ENODEV);
 225         }
 226
 227         return dev;
 228 }
 229
 230 static void ibmebus_probe_of_nodes(char* name)
 231 {
 232         struct device_node *dn = NULL;
 233
 234         while ((dn = of_find_node_by_name(dn, name))) {
 235                 if (IS_ERR(ibmebus_register_device_node(dn))) {
 236                         of_node_put(dn);
 237                         return;
 238                 }
 239         }
 240
 241         of_node_put(dn);
 242
 243         return;
 244 }
 245
 246 static void ibmebus_add_devices_by_id(struct of_device_id *idt)
 247 {
 248         while (strlen(idt->name) > 0) {
 249                 ibmebus_probe_of_nodes(idt->name);
 250                 idt++;
 251         }
 252
 253         return;
 254 }
 255
 256 static int ibmebus_match_helper_name(struct device *dev, void *data)
 257 {
 258         const struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);
 259         char *name;
 260
 261         name = (char*)get_property(
 262                 ebus_dev->ofdev.node, "name", NULL);
 263
 264         if (name && (strcmp((char*)data, name) == 0))
 265                 return 1;
 266
 267         return 0;
 268 }
 269
 270 static int ibmebus_unregister_device(struct device *dev)
 271 {
 272         of_device_unregister(to_of_device(dev));
 273
 274         return 0;
 275 }
 276
 277 static void ibmebus_remove_devices_by_id(struct of_device_id *idt)
 278 {
 279         struct device *dev;
 280
 281         while (strlen(idt->name) > 0) {
 282                 while ((dev = bus_find_device(&ibmebus_bus_type, NULL,
 283                                               (void*)idt->name,
 284                                               ibmebus_match_helper_name))) {
 285                         ibmebus_unregister_device(dev);
 286                 }
 287                 idt++;
 288         }
 289
 290         return;
 291 }
 292
 293 int ibmebus_register_driver(struct ibmebus_driver *drv)
 294 {
 295         int err = 0;
 296
 297         drv->driver.name   = drv->name;
 298         drv->driver.bus    = &ibmebus_bus_type;
 299         drv->driver.probe  = ibmebus_bus_probe;
 300         drv->driver.remove = ibmebus_bus_remove;
 301
 302         if ((err = driver_register(&drv->driver) != 0))
 303                 return err;
 304
 305         /* remove all supported devices first, in case someone
 306          * probed them manually before registering the driver */
 307         ibmebus_remove_devices_by_id(drv->id_table);
 308         ibmebus_add_devices_by_id(drv->id_table);
 309
 310         return 0;
 311 }
 312 EXPORT_SYMBOL(ibmebus_register_driver);
 313
 314 void ibmebus_unregister_driver(struct ibmebus_driver *drv)
 315 {
 316         driver_unregister(&drv->driver);
 317         ibmebus_remove_devices_by_id(drv->id_table);
 318 }
 319 EXPORT_SYMBOL(ibmebus_unregister_driver);
 320
 321 int ibmebus_request_irq(struct ibmebus_dev *dev,
 322                         u32 ist,
 323                         irq_handler_t handler,
 324                         unsigned long irq_flags, const char * devname,
 325                         void *dev_id)
 326 {
 327         unsigned int irq = irq_create_mapping(NULL, ist);
 328
 329         if (irq == NO_IRQ)
 330                 return -EINVAL;
 331
 332         return request_irq(irq, handler,
 333                            irq_flags, devname, dev_id);
 334 }
 335 EXPORT_SYMBOL(ibmebus_request_irq);
 336
 337 void ibmebus_free_irq(struct ibmebus_dev *dev, u32 ist, void *dev_id)
 338 {
 339         unsigned int irq = irq_find_mapping(NULL, ist);
 340
 341         free_irq(irq, dev_id);
 342 }
 343 EXPORT_SYMBOL(ibmebus_free_irq);
 344
 345 static int ibmebus_bus_match(struct device *dev, struct device_driver *drv)
 346 {
 347         const struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);
 348         struct ibmebus_driver *ebus_drv    = to_ibmebus_driver(drv);
 349         const struct of_device_id *ids     = ebus_drv->id_table;
 350         const struct of_device_id *found_id;
 351
 352         if (!ids)
 353                 return 0;
 354
 355         found_id = of_match_device(ids, &ebus_dev->ofdev);
 356         if (found_id)
 357                 return 1;
 358
 359         return 0;
 360 }
 361
 362 static ssize_t name_show(struct device *dev,
 363                          struct device_attribute *attr, char *buf)
 364 {
 365         struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);
 366         char *name = (char*)get_property(ebus_dev->ofdev.node, "name", NULL);
 367         return sprintf(buf, "%s\n", name);
 368 }
 369
 370 static struct device_attribute ibmebus_dev_attrs[] = {
 371         __ATTR_RO(name),
 372         __ATTR_NULL
 373 };
 374
 375 static int ibmebus_match_helper_loc_code(struct device *dev, void *data)
 376 {
 377         const struct ibmebus_dev *ebus_dev = to_ibmebus_dev(dev);
 378         char *loc_code;
 379
 380         loc_code = (char*)get_property(
 381                 ebus_dev->ofdev.node, "ibm,loc-code", NULL);
 382
 383         if (loc_code && (strcmp((char*)data, loc_code) == 0))
 384                 return 1;
 385
 386         return 0;
 387 }
 388
 389 static ssize_t ibmebus_store_probe(struct bus_type *bus,
 390                                    const char *buf, size_t count)
 391 {
 392         struct device_node *dn = NULL;
 393         struct ibmebus_dev *dev;
 394         char *loc_code;
 395         char parm[MAX_LOC_CODE_LENGTH];
 396
 397         if (count >= MAX_LOC_CODE_LENGTH)
 398                 return -EINVAL;
 399         memcpy(parm, buf, count);
 400         parm[count] = '\0';
 401         if (parm[count-1] == '\n')
 402                 parm[count-1] = '\0';
 403
 404         if (bus_find_device(&ibmebus_bus_type, NULL, parm,
 405                              ibmebus_match_helper_loc_code)) {
 406                 printk(KERN_WARNING "%s: loc_code %s has already been probed\n",
 407                        __FUNCTION__, parm);
 408                 return -EINVAL;
 409         }
 410
 411         while ((dn = of_find_all_nodes(dn))) {
 412                 loc_code = (char *)get_property(dn, "ibm,loc-code", NULL);
 413                 if (loc_code && (strncmp(loc_code, parm, count) == 0)) {
 414                         dev = ibmebus_register_device_node(dn);
 415                         if (IS_ERR(dev)) {
 416                                 of_node_put(dn);
 417                                 return PTR_ERR(dev);
 418                         } else
 419                                 return count; /* success */
 420                 }
 421         }
 422
 423         /* if we drop out of the loop, the loc code was invalid */
 424         printk(KERN_WARNING "%s: no device with loc_code %s found\n",
 425                __FUNCTION__, parm);
 426         return -ENODEV;
 427 }
 428
 429 static ssize_t ibmebus_store_remove(struct bus_type *bus,
 430                                     const char *buf, size_t count)
 431 {
 432         struct device *dev;
 433         char parm[MAX_LOC_CODE_LENGTH];
 434
 435         if (count >= MAX_LOC_CODE_LENGTH)
 436                 return -EINVAL;
 437         memcpy(parm, buf, count);
 438         parm[count] = '\0';
 439         if (parm[count-1] == '\n')
 440                 parm[count-1] = '\0';
 441
 442         /* The location code is unique, so we will find one device at most */
 443         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, parm,
 444                                    ibmebus_match_helper_loc_code))) {
 445                 ibmebus_unregister_device(dev);
 446         } else {
 447                 printk(KERN_WARNING "%s: loc_code %s not on the bus\n",
 448                        __FUNCTION__, parm);
 449                 return -ENODEV;
 450         }
 451
 452         return count;
 453 }
 454
 455 static struct bus_attribute ibmebus_bus_attrs[] = {
 456         __ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe),
 457         __ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove),
 458         __ATTR_NULL
 459 };
 460
 461 struct bus_type ibmebus_bus_type = {
 462         .name      = "ibmebus",
 463         .match     = ibmebus_bus_match,
 464         .dev_attrs = ibmebus_dev_attrs,
 465         .bus_attrs = ibmebus_bus_attrs
 466 };
 467 EXPORT_SYMBOL(ibmebus_bus_type);
 468
 469 static int __init ibmebus_bus_init(void)
 470 {
 471         int err;
 472
 473         printk(KERN_INFO "IBM eBus Device Driver\n");
 474
 475         err = bus_register(&ibmebus_bus_type);
 476         if (err) {
 477                 printk(KERN_ERR ":%s: failed to register IBM eBus.\n",
 478                        __FUNCTION__);
 479                 return err;
 480         }
 481
 482         err = device_register(&ibmebus_bus_device);
 483         if (err) {
 484                 printk(KERN_WARNING "%s: device_register returned %i\n",
 485                        __FUNCTION__, err);
 486                 bus_unregister(&ibmebus_bus_type);
 487
 488                 return err;
 489         }
 490
 491         return 0;
 492 }
 493 __initcall(ibmebus_bus_init);