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_platform.h>
  45 #include <asm/ibmebus.h>
  46 #include <asm/abs_addr.h>
  47
  48 static struct device ibmebus_bus_device = { /* fake "parent" device */
  49         .bus_id = "ibmebus",
  50 };
  51
  52 struct bus_type ibmebus_bus_type;
  53
  54 /* These devices will automatically be added to the bus during init */
  55 static struct of_device_id builtin_matches[] = {
  56         { .compatible = "IBM,lhca" },
  57         { .compatible = "IBM,lhea" },
  58         {},
  59 };
  60
  61 static void *ibmebus_alloc_coherent(struct device *dev,
  62                                     size_t size,
  63                                     dma_addr_t *dma_handle,
  64                                     gfp_t flag)
  65 {
  66         void *mem;
  67
  68         mem = kmalloc(size, flag);
  69         *dma_handle = (dma_addr_t)mem;
  70
  71         return mem;
  72 }
  73
  74 static void ibmebus_free_coherent(struct device *dev,
  75                                   size_t size, void *vaddr,
  76                                   dma_addr_t dma_handle)
  77 {
  78         kfree(vaddr);
  79 }
  80
  81 static dma_addr_t ibmebus_map_single(struct device *dev,
  82                                      void *ptr,
  83                                      size_t size,
  84                                      enum dma_data_direction direction)
  85 {
  86         return (dma_addr_t)(ptr);
  87 }
  88
  89 static void ibmebus_unmap_single(struct device *dev,
  90                                  dma_addr_t dma_addr,
  91                                  size_t size,
  92                                  enum dma_data_direction direction)
  93 {
  94         return;
  95 }
  96
  97 static int ibmebus_map_sg(struct device *dev,
  98                           struct scatterlist *sgl,
  99                           int nents, enum dma_data_direction direction)
 100 {
 101         struct scatterlist *sg;
 102         int i;
 103
 104         for_each_sg(sgl, sg, nents, i) {
 105                 sg->dma_address = (dma_addr_t) sg_virt(sg);
 106                 sg->dma_length = sg->length;
 107         }
 108
 109         return nents;
 110 }
 111
 112 static void ibmebus_unmap_sg(struct device *dev,
 113                              struct scatterlist *sg,
 114                              int nents, enum dma_data_direction direction)
 115 {
 116         return;
 117 }
 118
 119 static int ibmebus_dma_supported(struct device *dev, u64 mask)
 120 {
 121         return 1;
 122 }
 123
 124 static struct dma_mapping_ops ibmebus_dma_ops = {
 125         .alloc_coherent = ibmebus_alloc_coherent,
 126         .free_coherent  = ibmebus_free_coherent,
 127         .map_single     = ibmebus_map_single,
 128         .unmap_single   = ibmebus_unmap_single,
 129         .map_sg         = ibmebus_map_sg,
 130         .unmap_sg       = ibmebus_unmap_sg,
 131         .dma_supported  = ibmebus_dma_supported,
 132 };
 133
 134 static int ibmebus_match_path(struct device *dev, void *data)
 135 {
 136         struct device_node *dn = to_of_device(dev)->node;
 137         return (dn->full_name &&
 138                 (strcasecmp((char *)data, dn->full_name) == 0));
 139 }
 140
 141 static int ibmebus_match_node(struct device *dev, void *data)
 142 {
 143         return to_of_device(dev)->node == data;
 144 }
 145
 146 static int ibmebus_create_device(struct device_node *dn)
 147 {
 148         struct of_device *dev;
 149         int ret;
 150
 151         dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
 152         if (!dev)
 153                 return -ENOMEM;
 154
 155         dev->dev.bus = &ibmebus_bus_type;
 156         dev->dev.archdata.dma_ops = &ibmebus_dma_ops;
 157
 158         ret = of_device_register(dev);
 159         if (ret) {
 160                 of_device_free(dev);
 161                 return ret;
 162         }
 163
 164         return 0;
 165 }
 166
 167 static int ibmebus_create_devices(const struct of_device_id *matches)
 168 {
 169         struct device_node *root, *child;
 170         int ret = 0;
 171
 172         root = of_find_node_by_path("/");
 173
 174         for (child = NULL; (child = of_get_next_child(root, child)); ) {
 175                 if (!of_match_node(matches, child))
 176                         continue;
 177
 178                 if (bus_find_device(&ibmebus_bus_type, NULL, child,
 179                                     ibmebus_match_node))
 180                         continue;
 181
 182                 ret = ibmebus_create_device(child);
 183                 if (ret) {
 184                         printk(KERN_ERR "%s: failed to create device (%i)",
 185                                __FUNCTION__, ret);
 186                         of_node_put(child);
 187                         break;
 188                 }
 189         }
 190
 191         of_node_put(root);
 192         return ret;
 193 }
 194
 195 int ibmebus_register_driver(struct of_platform_driver *drv)
 196 {
 197         /* If the driver uses devices that ibmebus doesn't know, add them */
 198         ibmebus_create_devices(drv->match_table);
 199
 200         drv->driver.name   = drv->name;
 201         drv->driver.bus    = &ibmebus_bus_type;
 202
 203         return driver_register(&drv->driver);
 204 }
 205 EXPORT_SYMBOL(ibmebus_register_driver);
 206
 207 void ibmebus_unregister_driver(struct of_platform_driver *drv)
 208 {
 209         driver_unregister(&drv->driver);
 210 }
 211 EXPORT_SYMBOL(ibmebus_unregister_driver);
 212
 213 int ibmebus_request_irq(u32 ist, irq_handler_t handler,
 214                         unsigned long irq_flags, const char *devname,
 215                         void *dev_id)
 216 {
 217         unsigned int irq = irq_create_mapping(NULL, ist);
 218
 219         if (irq == NO_IRQ)
 220                 return -EINVAL;
 221
 222         return request_irq(irq, handler, irq_flags, devname, dev_id);
 223 }
 224 EXPORT_SYMBOL(ibmebus_request_irq);
 225
 226 void ibmebus_free_irq(u32 ist, void *dev_id)
 227 {
 228         unsigned int irq = irq_find_mapping(NULL, ist);
 229
 230         free_irq(irq, dev_id);
 231 }
 232 EXPORT_SYMBOL(ibmebus_free_irq);
 233
 234 static ssize_t name_show(struct device *dev,
 235                          struct device_attribute *attr, char *buf)
 236 {
 237         return sprintf(buf, "%s\n", to_of_device(dev)->node->name);
 238 }
 239
 240 static struct device_attribute ibmebus_dev_attrs[] = {
 241         __ATTR_RO(name),
 242         __ATTR_NULL
 243 };
 244
 245 static char *ibmebus_chomp(const char *in, size_t count)
 246 {
 247         char *out = kmalloc(count + 1, GFP_KERNEL);
 248
 249         if (!out)
 250                 return NULL;
 251
 252         memcpy(out, in, count);
 253         out[count] = '\0';
 254         if (out[count - 1] == '\n')
 255                 out[count - 1] = '\0';
 256
 257         return out;
 258 }
 259
 260 static ssize_t ibmebus_store_probe(struct bus_type *bus,
 261                                    const char *buf, size_t count)
 262 {
 263         struct device_node *dn = NULL;
 264         char *path;
 265         ssize_t rc = 0;
 266
 267         path = ibmebus_chomp(buf, count);
 268         if (!path)
 269                 return -ENOMEM;
 270
 271         if (bus_find_device(&ibmebus_bus_type, NULL, path,
 272                             ibmebus_match_path)) {
 273                 printk(KERN_WARNING "%s: %s has already been probed\n",
 274                        __FUNCTION__, path);
 275                 rc = -EEXIST;
 276                 goto out;
 277         }
 278
 279         if ((dn = of_find_node_by_path(path))) {
 280                 rc = ibmebus_create_device(dn);
 281                 of_node_put(dn);
 282         } else {
 283                 printk(KERN_WARNING "%s: no such device node: %s\n",
 284                        __FUNCTION__, path);
 285                 rc = -ENODEV;
 286         }
 287
 288 out:
 289         kfree(path);
 290         if (rc)
 291                 return rc;
 292         return count;
 293 }
 294
 295 static ssize_t ibmebus_store_remove(struct bus_type *bus,
 296                                     const char *buf, size_t count)
 297 {
 298         struct device *dev;
 299         char *path;
 300
 301         path = ibmebus_chomp(buf, count);
 302         if (!path)
 303                 return -ENOMEM;
 304
 305         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
 306                                    ibmebus_match_path))) {
 307                 of_device_unregister(to_of_device(dev));
 308
 309                 kfree(path);
 310                 return count;
 311         } else {
 312                 printk(KERN_WARNING "%s: %s not on the bus\n",
 313                        __FUNCTION__, path);
 314
 315                 kfree(path);
 316                 return -ENODEV;
 317         }
 318 }
 319
 320 static struct bus_attribute ibmebus_bus_attrs[] = {
 321         __ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe),
 322         __ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove),
 323         __ATTR_NULL
 324 };
 325
 326 struct bus_type ibmebus_bus_type = {
 327         .uevent    = of_device_uevent,
 328         .dev_attrs = ibmebus_dev_attrs,
 329         .bus_attrs = ibmebus_bus_attrs
 330 };
 331 EXPORT_SYMBOL(ibmebus_bus_type);
 332
 333 static int __init ibmebus_bus_init(void)
 334 {
 335         int err;
 336
 337         printk(KERN_INFO "IBM eBus Device Driver\n");
 338
 339         err = of_bus_type_init(&ibmebus_bus_type, "ibmebus");
 340         if (err) {
 341                 printk(KERN_ERR "%s: failed to register IBM eBus.\n",
 342                        __FUNCTION__);
 343                 return err;
 344         }
 345
 346         err = device_register(&ibmebus_bus_device);
 347         if (err) {
 348                 printk(KERN_WARNING "%s: device_register returned %i\n",
 349                        __FUNCTION__, err);
 350                 bus_unregister(&ibmebus_bus_type);
 351
 352                 return err;
 353         }
 354
 355         err = ibmebus_create_devices(builtin_matches);
 356         if (err) {
 357                 device_unregister(&ibmebus_bus_device);
 358                 bus_unregister(&ibmebus_bus_type);
 359                 return err;
 360         }
 361
 362         return 0;
 363 }
 364 postcore_initcall(ibmebus_bus_init);