arch/powerpc/platforms/pseries/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/export.h>
  41 #include <linux/console.h>
  42 #include <linux/kobject.h>
  43 #include <linux/dma-mapping.h>
  44 #include <linux/interrupt.h>
  45 #include <linux/of.h>
  46 #include <linux/slab.h>
  47 #include <linux/stat.h>
  48 #include <linux/of_platform.h>
  49 #include <asm/ibmebus.h>
  50
  51 static struct device ibmebus_bus_device = { /* fake "parent" device */
  52         .init_name = "ibmebus",
  53 };
  54
  55 struct bus_type ibmebus_bus_type;
  56
  57 /* These devices will automatically be added to the bus during init */
  58 static const struct of_device_id ibmebus_matches[] __initconst = {
  59         { .compatible = "IBM,lhca" },
  60         { .compatible = "IBM,lhea" },
  61         {},
  62 };
  63
  64 static void *ibmebus_alloc_coherent(struct device *dev,
  65                                     size_t size,
  66                                     dma_addr_t *dma_handle,
  67                                     gfp_t flag,
  68                                     unsigned long attrs)
  69 {
  70         void *mem;
  71
  72         mem = kmalloc(size, flag);
  73         *dma_handle = (dma_addr_t)mem;
  74
  75         return mem;
  76 }
  77
  78 static void ibmebus_free_coherent(struct device *dev,
  79                                   size_t size, void *vaddr,
  80                                   dma_addr_t dma_handle,
  81                                   unsigned long attrs)
  82 {
  83         kfree(vaddr);
  84 }
  85
  86 static dma_addr_t ibmebus_map_page(struct device *dev,
  87                                    struct page *page,
  88                                    unsigned long offset,
  89                                    size_t size,
  90                                    enum dma_data_direction direction,
  91                                    unsigned long attrs)
  92 {
  93         return (dma_addr_t)(page_address(page) + offset);
  94 }
  95
  96 static void ibmebus_unmap_page(struct device *dev,
  97                                dma_addr_t dma_addr,
  98                                size_t size,
  99                                enum dma_data_direction direction,
 100                                unsigned long attrs)
 101 {
 102         return;
 103 }
 104
 105 static int ibmebus_map_sg(struct device *dev,
 106                           struct scatterlist *sgl,
 107                           int nents, enum dma_data_direction direction,
 108                           unsigned long attrs)
 109 {
 110         struct scatterlist *sg;
 111         int i;
 112
 113         for_each_sg(sgl, sg, nents, i) {
 114                 sg->dma_address = (dma_addr_t) sg_virt(sg);
 115                 sg->dma_length = sg->length;
 116         }
 117
 118         return nents;
 119 }
 120
 121 static void ibmebus_unmap_sg(struct device *dev,
 122                              struct scatterlist *sg,
 123                              int nents, enum dma_data_direction direction,
 124                              unsigned long attrs)
 125 {
 126         return;
 127 }
 128
 129 static int ibmebus_dma_supported(struct device *dev, u64 mask)
 130 {
 131         return mask == DMA_BIT_MASK(64);
 132 }
 133
 134 static u64 ibmebus_dma_get_required_mask(struct device *dev)
 135 {
 136         return DMA_BIT_MASK(64);
 137 }
 138
 139 static const struct dma_map_ops ibmebus_dma_ops = {
 140         .alloc              = ibmebus_alloc_coherent,
 141         .free               = ibmebus_free_coherent,
 142         .map_sg             = ibmebus_map_sg,
 143         .unmap_sg           = ibmebus_unmap_sg,
 144         .dma_supported      = ibmebus_dma_supported,
 145         .get_required_mask  = ibmebus_dma_get_required_mask,
 146         .map_page           = ibmebus_map_page,
 147         .unmap_page         = ibmebus_unmap_page,
 148 };
 149
 150 static int ibmebus_match_path(struct device *dev, void *data)
 151 {
 152         struct device_node *dn = to_platform_device(dev)->dev.of_node;
 153         return (dn->full_name &&
 154                 (strcasecmp((char *)data, dn->full_name) == 0));
 155 }
 156
 157 static int ibmebus_match_node(struct device *dev, void *data)
 158 {
 159         return to_platform_device(dev)->dev.of_node == data;
 160 }
 161
 162 static int ibmebus_create_device(struct device_node *dn)
 163 {
 164         struct platform_device *dev;
 165         int ret;
 166
 167         dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
 168         if (!dev)
 169                 return -ENOMEM;
 170
 171         dev->dev.bus = &ibmebus_bus_type;
 172         dev->dev.dma_ops = &ibmebus_dma_ops;
 173
 174         ret = of_device_add(dev);
 175         if (ret)
 176                 platform_device_put(dev);
 177         return ret;
 178 }
 179
 180 static int ibmebus_create_devices(const struct of_device_id *matches)
 181 {
 182         struct device_node *root, *child;
 183         struct device *dev;
 184         int ret = 0;
 185
 186         root = of_find_node_by_path("/");
 187
 188         for_each_child_of_node(root, child) {
 189                 if (!of_match_node(matches, child))
 190                         continue;
 191
 192                 dev = bus_find_device(&ibmebus_bus_type, NULL, child,
 193                                       ibmebus_match_node);
 194                 if (dev) {
 195                         put_device(dev);
 196                         continue;
 197                 }
 198
 199                 ret = ibmebus_create_device(child);
 200                 if (ret) {
 201                         printk(KERN_ERR "%s: failed to create device (%i)",
 202                                __func__, ret);
 203                         of_node_put(child);
 204                         break;
 205                 }
 206         }
 207
 208         of_node_put(root);
 209         return ret;
 210 }
 211
 212 int ibmebus_register_driver(struct platform_driver *drv)
 213 {
 214         /* If the driver uses devices that ibmebus doesn't know, add them */
 215         ibmebus_create_devices(drv->driver.of_match_table);
 216
 217         drv->driver.bus = &ibmebus_bus_type;
 218         return driver_register(&drv->driver);
 219 }
 220 EXPORT_SYMBOL(ibmebus_register_driver);
 221
 222 void ibmebus_unregister_driver(struct platform_driver *drv)
 223 {
 224         driver_unregister(&drv->driver);
 225 }
 226 EXPORT_SYMBOL(ibmebus_unregister_driver);
 227
 228 int ibmebus_request_irq(u32 ist, irq_handler_t handler,
 229                         unsigned long irq_flags, const char *devname,
 230                         void *dev_id)
 231 {
 232         unsigned int irq = irq_create_mapping(NULL, ist);
 233
 234         if (!irq)
 235                 return -EINVAL;
 236
 237         return request_irq(irq, handler, irq_flags, devname, dev_id);
 238 }
 239 EXPORT_SYMBOL(ibmebus_request_irq);
 240
 241 void ibmebus_free_irq(u32 ist, void *dev_id)
 242 {
 243         unsigned int irq = irq_find_mapping(NULL, ist);
 244
 245         free_irq(irq, dev_id);
 246         irq_dispose_mapping(irq);
 247 }
 248 EXPORT_SYMBOL(ibmebus_free_irq);
 249
 250 static char *ibmebus_chomp(const char *in, size_t count)
 251 {
 252         char *out = kmalloc(count + 1, GFP_KERNEL);
 253
 254         if (!out)
 255                 return NULL;
 256
 257         memcpy(out, in, count);
 258         out[count] = '\0';
 259         if (out[count - 1] == '\n')
 260                 out[count - 1] = '\0';
 261
 262         return out;
 263 }
 264
 265 static ssize_t ibmebus_store_probe(struct bus_type *bus,
 266                                    const char *buf, size_t count)
 267 {
 268         struct device_node *dn = NULL;
 269         struct device *dev;
 270         char *path;
 271         ssize_t rc = 0;
 272
 273         path = ibmebus_chomp(buf, count);
 274         if (!path)
 275                 return -ENOMEM;
 276
 277         dev = bus_find_device(&ibmebus_bus_type, NULL, path,
 278                               ibmebus_match_path);
 279         if (dev) {
 280                 put_device(dev);
 281                 printk(KERN_WARNING "%s: %s has already been probed\n",
 282                        __func__, path);
 283                 rc = -EEXIST;
 284                 goto out;
 285         }
 286
 287         if ((dn = of_find_node_by_path(path))) {
 288                 rc = ibmebus_create_device(dn);
 289                 of_node_put(dn);
 290         } else {
 291                 printk(KERN_WARNING "%s: no such device node: %s\n",
 292                        __func__, path);
 293                 rc = -ENODEV;
 294         }
 295
 296 out:
 297         kfree(path);
 298         if (rc)
 299                 return rc;
 300         return count;
 301 }
 302 static BUS_ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe);
 303
 304 static ssize_t ibmebus_store_remove(struct bus_type *bus,
 305                                     const char *buf, size_t count)
 306 {
 307         struct device *dev;
 308         char *path;
 309
 310         path = ibmebus_chomp(buf, count);
 311         if (!path)
 312                 return -ENOMEM;
 313
 314         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
 315                                    ibmebus_match_path))) {
 316                 of_device_unregister(to_platform_device(dev));
 317                 put_device(dev);
 318
 319                 kfree(path);
 320                 return count;
 321         } else {
 322                 printk(KERN_WARNING "%s: %s not on the bus\n",
 323                        __func__, path);
 324
 325                 kfree(path);
 326                 return -ENODEV;
 327         }
 328 }
 329 static BUS_ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove);
 330
 331 static struct attribute *ibmbus_bus_attrs[] = {
 332         &bus_attr_probe.attr,
 333         &bus_attr_remove.attr,
 334         NULL,
 335 };
 336 ATTRIBUTE_GROUPS(ibmbus_bus);
 337
 338 static int ibmebus_bus_bus_match(struct device *dev, struct device_driver *drv)
 339 {
 340         const struct of_device_id *matches = drv->of_match_table;
 341
 342         if (!matches)
 343                 return 0;
 344
 345         return of_match_device(matches, dev) != NULL;
 346 }
 347
 348 static int ibmebus_bus_device_probe(struct device *dev)
 349 {
 350         int error = -ENODEV;
 351         struct platform_driver *drv;
 352         struct platform_device *of_dev;
 353
 354         drv = to_platform_driver(dev->driver);
 355         of_dev = to_platform_device(dev);
 356
 357         if (!drv->probe)
 358                 return error;
 359
 360         of_dev_get(of_dev);
 361
 362         if (of_driver_match_device(dev, dev->driver))
 363                 error = drv->probe(of_dev);
 364         if (error)
 365                 of_dev_put(of_dev);
 366
 367         return error;
 368 }
 369
 370 static int ibmebus_bus_device_remove(struct device *dev)
 371 {
 372         struct platform_device *of_dev = to_platform_device(dev);
 373         struct platform_driver *drv = to_platform_driver(dev->driver);
 374
 375         if (dev->driver && drv->remove)
 376                 drv->remove(of_dev);
 377         return 0;
 378 }
 379
 380 static void ibmebus_bus_device_shutdown(struct device *dev)
 381 {
 382         struct platform_device *of_dev = to_platform_device(dev);
 383         struct platform_driver *drv = to_platform_driver(dev->driver);
 384
 385         if (dev->driver && drv->shutdown)
 386                 drv->shutdown(of_dev);
 387 }
 388
 389 /*
 390  * ibmebus_bus_device_attrs
 391  */
 392 static ssize_t devspec_show(struct device *dev,
 393                                 struct device_attribute *attr, char *buf)
 394 {
 395         struct platform_device *ofdev;
 396
 397         ofdev = to_platform_device(dev);
 398         return sprintf(buf, "%s\n", ofdev->dev.of_node->full_name);
 399 }
 400
 401 static ssize_t name_show(struct device *dev,
 402                                 struct device_attribute *attr, char *buf)
 403 {
 404         struct platform_device *ofdev;
 405
 406         ofdev = to_platform_device(dev);
 407         return sprintf(buf, "%s\n", ofdev->dev.of_node->name);
 408 }
 409
 410 static ssize_t modalias_show(struct device *dev,
 411                                 struct device_attribute *attr, char *buf)
 412 {
 413         return of_device_modalias(dev, buf, PAGE_SIZE);
 414 }
 415
 416 static struct device_attribute ibmebus_bus_device_attrs[] = {
 417         __ATTR_RO(devspec),
 418         __ATTR_RO(name),
 419         __ATTR_RO(modalias),
 420         __ATTR_NULL
 421 };
 422
 423 struct bus_type ibmebus_bus_type = {
 424         .name      = "ibmebus",
 425         .uevent    = of_device_uevent_modalias,
 426         .bus_groups = ibmbus_bus_groups,
 427         .match     = ibmebus_bus_bus_match,
 428         .probe     = ibmebus_bus_device_probe,
 429         .remove    = ibmebus_bus_device_remove,
 430         .shutdown  = ibmebus_bus_device_shutdown,
 431         .dev_attrs = ibmebus_bus_device_attrs,
 432 };
 433 EXPORT_SYMBOL(ibmebus_bus_type);
 434
 435 static int __init ibmebus_bus_init(void)
 436 {
 437         int err;
 438
 439         printk(KERN_INFO "IBM eBus Device Driver\n");
 440
 441         err = bus_register(&ibmebus_bus_type);
 442         if (err) {
 443                 printk(KERN_ERR "%s: failed to register IBM eBus.\n",
 444                        __func__);
 445                 return err;
 446         }
 447
 448         err = device_register(&ibmebus_bus_device);
 449         if (err) {
 450                 printk(KERN_WARNING "%s: device_register returned %i\n",
 451                        __func__, err);
 452                 bus_unregister(&ibmebus_bus_type);
 453
 454                 return err;
 455         }
 456
 457         err = ibmebus_create_devices(ibmebus_matches);
 458         if (err) {
 459                 device_unregister(&ibmebus_bus_device);
 460                 bus_unregister(&ibmebus_bus_type);
 461                 return err;
 462         }
 463
 464         return 0;
 465 }
 466 postcore_initcall(ibmebus_bus_init);