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 <linux/of.h>
  45 #include <linux/of_platform.h>
  46 #include <asm/ibmebus.h>
  47 #include <asm/abs_addr.h>
  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 /* These devices will automatically be added to the bus during init */
  56 static struct of_device_id __initdata ibmebus_matches[] = {
  57         { .compatible = "IBM,lhca" },
  58         { .compatible = "IBM,lhea" },
  59         {},
  60 };
  61
  62 static void *ibmebus_alloc_coherent(struct device *dev,
  63                                     size_t size,
  64                                     dma_addr_t *dma_handle,
  65                                     gfp_t flag)
  66 {
  67         void *mem;
  68
  69         mem = kmalloc(size, flag);
  70         *dma_handle = (dma_addr_t)mem;
  71
  72         return mem;
  73 }
  74
  75 static void ibmebus_free_coherent(struct device *dev,
  76                                   size_t size, void *vaddr,
  77                                   dma_addr_t dma_handle)
  78 {
  79         kfree(vaddr);
  80 }
  81
  82 static dma_addr_t ibmebus_map_single(struct device *dev,
  83                                      void *ptr,
  84                                      size_t size,
  85                                      enum dma_data_direction direction,
  86                                      struct dma_attrs *attrs)
  87 {
  88         return (dma_addr_t)(ptr);
  89 }
  90
  91 static void ibmebus_unmap_single(struct device *dev,
  92                                  dma_addr_t dma_addr,
  93                                  size_t size,
  94                                  enum dma_data_direction direction,
  95                                  struct dma_attrs *attrs)
  96 {
  97         return;
  98 }
  99
 100 static int ibmebus_map_sg(struct device *dev,
 101                           struct scatterlist *sgl,
 102                           int nents, enum dma_data_direction direction,
 103                           struct dma_attrs *attrs)
 104 {
 105         struct scatterlist *sg;
 106         int i;
 107
 108         for_each_sg(sgl, sg, nents, i) {
 109                 sg->dma_address = (dma_addr_t) sg_virt(sg);
 110                 sg->dma_length = sg->length;
 111         }
 112
 113         return nents;
 114 }
 115
 116 static void ibmebus_unmap_sg(struct device *dev,
 117                              struct scatterlist *sg,
 118                              int nents, enum dma_data_direction direction,
 119                              struct dma_attrs *attrs)
 120 {
 121         return;
 122 }
 123
 124 static int ibmebus_dma_supported(struct device *dev, u64 mask)
 125 {
 126         return 1;
 127 }
 128
 129 static struct dma_mapping_ops ibmebus_dma_ops = {
 130         .alloc_coherent = ibmebus_alloc_coherent,
 131         .free_coherent  = ibmebus_free_coherent,
 132         .map_single     = ibmebus_map_single,
 133         .unmap_single   = ibmebus_unmap_single,
 134         .map_sg         = ibmebus_map_sg,
 135         .unmap_sg       = ibmebus_unmap_sg,
 136         .dma_supported  = ibmebus_dma_supported,
 137 };
 138
 139 static int ibmebus_match_path(struct device *dev, void *data)
 140 {
 141         struct device_node *dn = to_of_device(dev)->node;
 142         return (dn->full_name &&
 143                 (strcasecmp((char *)data, dn->full_name) == 0));
 144 }
 145
 146 static int ibmebus_match_node(struct device *dev, void *data)
 147 {
 148         return to_of_device(dev)->node == data;
 149 }
 150
 151 static int ibmebus_create_device(struct device_node *dn)
 152 {
 153         struct of_device *dev;
 154         int ret;
 155
 156         dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
 157         if (!dev)
 158                 return -ENOMEM;
 159
 160         dev->dev.bus = &ibmebus_bus_type;
 161         dev->dev.archdata.dma_ops = &ibmebus_dma_ops;
 162
 163         ret = of_device_register(dev);
 164         if (ret) {
 165                 of_device_free(dev);
 166                 return ret;
 167         }
 168
 169         return 0;
 170 }
 171
 172 static int ibmebus_create_devices(const struct of_device_id *matches)
 173 {
 174         struct device_node *root, *child;
 175         int ret = 0;
 176
 177         root = of_find_node_by_path("/");
 178
 179         for_each_child_of_node(root, child) {
 180                 if (!of_match_node(matches, child))
 181                         continue;
 182
 183                 if (bus_find_device(&ibmebus_bus_type, NULL, child,
 184                                     ibmebus_match_node))
 185                         continue;
 186
 187                 ret = ibmebus_create_device(child);
 188                 if (ret) {
 189                         printk(KERN_ERR "%s: failed to create device (%i)",
 190                                __func__, ret);
 191                         of_node_put(child);
 192                         break;
 193                 }
 194         }
 195
 196         of_node_put(root);
 197         return ret;
 198 }
 199
 200 int ibmebus_register_driver(struct of_platform_driver *drv)
 201 {
 202         /* If the driver uses devices that ibmebus doesn't know, add them */
 203         ibmebus_create_devices(drv->match_table);
 204
 205         return of_register_driver(drv, &ibmebus_bus_type);
 206 }
 207 EXPORT_SYMBOL(ibmebus_register_driver);
 208
 209 void ibmebus_unregister_driver(struct of_platform_driver *drv)
 210 {
 211         of_unregister_driver(drv);
 212 }
 213 EXPORT_SYMBOL(ibmebus_unregister_driver);
 214
 215 int ibmebus_request_irq(u32 ist, irq_handler_t handler,
 216                         unsigned long irq_flags, const char *devname,
 217                         void *dev_id)
 218 {
 219         unsigned int irq = irq_create_mapping(NULL, ist);
 220
 221         if (irq == NO_IRQ)
 222                 return -EINVAL;
 223
 224         return request_irq(irq, handler, irq_flags, devname, dev_id);
 225 }
 226 EXPORT_SYMBOL(ibmebus_request_irq);
 227
 228 void ibmebus_free_irq(u32 ist, void *dev_id)
 229 {
 230         unsigned int irq = irq_find_mapping(NULL, ist);
 231
 232         free_irq(irq, dev_id);
 233 }
 234 EXPORT_SYMBOL(ibmebus_free_irq);
 235
 236 static char *ibmebus_chomp(const char *in, size_t count)
 237 {
 238         char *out = kmalloc(count + 1, GFP_KERNEL);
 239
 240         if (!out)
 241                 return NULL;
 242
 243         memcpy(out, in, count);
 244         out[count] = '\0';
 245         if (out[count - 1] == '\n')
 246                 out[count - 1] = '\0';
 247
 248         return out;
 249 }
 250
 251 static ssize_t ibmebus_store_probe(struct bus_type *bus,
 252                                    const char *buf, size_t count)
 253 {
 254         struct device_node *dn = NULL;
 255         char *path;
 256         ssize_t rc = 0;
 257
 258         path = ibmebus_chomp(buf, count);
 259         if (!path)
 260                 return -ENOMEM;
 261
 262         if (bus_find_device(&ibmebus_bus_type, NULL, path,
 263                             ibmebus_match_path)) {
 264                 printk(KERN_WARNING "%s: %s has already been probed\n",
 265                        __func__, path);
 266                 rc = -EEXIST;
 267                 goto out;
 268         }
 269
 270         if ((dn = of_find_node_by_path(path))) {
 271                 rc = ibmebus_create_device(dn);
 272                 of_node_put(dn);
 273         } else {
 274                 printk(KERN_WARNING "%s: no such device node: %s\n",
 275                        __func__, path);
 276                 rc = -ENODEV;
 277         }
 278
 279 out:
 280         kfree(path);
 281         if (rc)
 282                 return rc;
 283         return count;
 284 }
 285
 286 static ssize_t ibmebus_store_remove(struct bus_type *bus,
 287                                     const char *buf, size_t count)
 288 {
 289         struct device *dev;
 290         char *path;
 291
 292         path = ibmebus_chomp(buf, count);
 293         if (!path)
 294                 return -ENOMEM;
 295
 296         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
 297                                    ibmebus_match_path))) {
 298                 of_device_unregister(to_of_device(dev));
 299
 300                 kfree(path);
 301                 return count;
 302         } else {
 303                 printk(KERN_WARNING "%s: %s not on the bus\n",
 304                        __func__, path);
 305
 306                 kfree(path);
 307                 return -ENODEV;
 308         }
 309 }
 310
 311 static struct bus_attribute ibmebus_bus_attrs[] = {
 312         __ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe),
 313         __ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove),
 314         __ATTR_NULL
 315 };
 316
 317 struct bus_type ibmebus_bus_type = {
 318         .uevent    = of_device_uevent,
 319         .bus_attrs = ibmebus_bus_attrs
 320 };
 321 EXPORT_SYMBOL(ibmebus_bus_type);
 322
 323 static int __init ibmebus_bus_init(void)
 324 {
 325         int err;
 326
 327         printk(KERN_INFO "IBM eBus Device Driver\n");
 328
 329         err = of_bus_type_init(&ibmebus_bus_type, "ibmebus");
 330         if (err) {
 331                 printk(KERN_ERR "%s: failed to register IBM eBus.\n",
 332                        __func__);
 333                 return err;
 334         }
 335
 336         err = device_register(&ibmebus_bus_device);
 337         if (err) {
 338                 printk(KERN_WARNING "%s: device_register returned %i\n",
 339                        __func__, err);
 340                 bus_unregister(&ibmebus_bus_type);
 341
 342                 return err;
 343         }
 344
 345         err = ibmebus_create_devices(ibmebus_matches);
 346         if (err) {
 347                 device_unregister(&ibmebus_bus_device);
 348                 bus_unregister(&ibmebus_bus_type);
 349                 return err;
 350         }
 351
 352         return 0;
 353 }
 354 postcore_initcall(ibmebus_bus_init);