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