release/src-rt-6.x.4708/linux/linux-2.6.36/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/slab.h>
  46 #include <linux/of_platform.h>
  47 #include <asm/ibmebus.h>
  48 #include <asm/abs_addr.h>
  49
  50 static struct device ibmebus_bus_device = { /* fake "parent" device */
  51         .init_name = "ibmebus",
  52 };
  53
  54 struct bus_type ibmebus_bus_type;
  55
  56 /* These devices will automatically be added to the bus during init */
  57 static struct of_device_id __initdata ibmebus_matches[] = {
  58         { .compatible = "IBM,lhca" },
  59         { .compatible = "IBM,lhea" },
  60         {},
  61 };
  62
  63 static void *ibmebus_alloc_coherent(struct device *dev,
  64                                     size_t size,
  65                                     dma_addr_t *dma_handle,
  66                                     gfp_t flag)
  67 {
  68         void *mem;
  69
  70         mem = kmalloc(size, flag);
  71         *dma_handle = (dma_addr_t)mem;
  72
  73         return mem;
  74 }
  75
  76 static void ibmebus_free_coherent(struct device *dev,
  77                                   size_t size, void *vaddr,
  78                                   dma_addr_t dma_handle)
  79 {
  80         kfree(vaddr);
  81 }
  82
  83 static dma_addr_t ibmebus_map_page(struct device *dev,
  84                                    struct page *page,
  85                                    unsigned long offset,
  86                                    size_t size,
  87                                    enum dma_data_direction direction,
  88                                    struct dma_attrs *attrs)
  89 {
  90         return (dma_addr_t)(page_address(page) + offset);
  91 }
  92
  93 static void ibmebus_unmap_page(struct device *dev,
  94                                dma_addr_t dma_addr,
  95                                size_t size,
  96                                enum dma_data_direction direction,
  97                                struct dma_attrs *attrs)
  98 {
  99         return;
 100 }
 101
 102 static int ibmebus_map_sg(struct device *dev,
 103                           struct scatterlist *sgl,
 104                           int nents, enum dma_data_direction direction,
 105                           struct dma_attrs *attrs)
 106 {
 107         struct scatterlist *sg;
 108         int i;
 109
 110         for_each_sg(sgl, sg, nents, i) {
 111                 sg->dma_address = (dma_addr_t) sg_virt(sg);
 112                 sg->dma_length = sg->length;
 113         }
 114
 115         return nents;
 116 }
 117
 118 static void ibmebus_unmap_sg(struct device *dev,
 119                              struct scatterlist *sg,
 120                              int nents, enum dma_data_direction direction,
 121                              struct dma_attrs *attrs)
 122 {
 123         return;
 124 }
 125
 126 static int ibmebus_dma_supported(struct device *dev, u64 mask)
 127 {
 128         return 1;
 129 }
 130
 131 static struct dma_map_ops ibmebus_dma_ops = {
 132         .alloc_coherent = ibmebus_alloc_coherent,
 133         .free_coherent  = ibmebus_free_coherent,
 134         .map_sg         = ibmebus_map_sg,
 135         .unmap_sg       = ibmebus_unmap_sg,
 136         .dma_supported  = ibmebus_dma_supported,
 137         .map_page       = ibmebus_map_page,
 138         .unmap_page     = ibmebus_unmap_page,
 139 };
 140
 141 static int ibmebus_match_path(struct device *dev, void *data)
 142 {
 143         struct device_node *dn = to_platform_device(dev)->dev.of_node;
 144         return (dn->full_name &&
 145                 (strcasecmp((char *)data, dn->full_name) == 0));
 146 }
 147
 148 static int ibmebus_match_node(struct device *dev, void *data)
 149 {
 150         return to_platform_device(dev)->dev.of_node == data;
 151 }
 152
 153 static int ibmebus_create_device(struct device_node *dn)
 154 {
 155         struct platform_device *dev;
 156         int ret;
 157
 158         dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
 159         if (!dev)
 160                 return -ENOMEM;
 161
 162         dev->dev.bus = &ibmebus_bus_type;
 163         dev->dev.archdata.dma_ops = &ibmebus_dma_ops;
 164
 165         ret = of_device_register(dev);
 166         if (ret) {
 167                 of_device_free(dev);
 168                 return ret;
 169         }
 170
 171         return 0;
 172 }
 173
 174 static int ibmebus_create_devices(const struct of_device_id *matches)
 175 {
 176         struct device_node *root, *child;
 177         int ret = 0;
 178
 179         root = of_find_node_by_path("/");
 180
 181         for_each_child_of_node(root, child) {
 182                 if (!of_match_node(matches, child))
 183                         continue;
 184
 185                 if (bus_find_device(&ibmebus_bus_type, NULL, child,
 186                                     ibmebus_match_node))
 187                         continue;
 188
 189                 ret = ibmebus_create_device(child);
 190                 if (ret) {
 191                         printk(KERN_ERR "%s: failed to create device (%i)",
 192                                __func__, ret);
 193                         of_node_put(child);
 194                         break;
 195                 }
 196         }
 197
 198         of_node_put(root);
 199         return ret;
 200 }
 201
 202 int ibmebus_register_driver(struct of_platform_driver *drv)
 203 {
 204         /* If the driver uses devices that ibmebus doesn't know, add them */
 205         ibmebus_create_devices(drv->driver.of_match_table);
 206
 207         return of_register_driver(drv, &ibmebus_bus_type);
 208 }
 209 EXPORT_SYMBOL(ibmebus_register_driver);
 210
 211 void ibmebus_unregister_driver(struct of_platform_driver *drv)
 212 {
 213         of_unregister_driver(drv);
 214 }
 215 EXPORT_SYMBOL(ibmebus_unregister_driver);
 216
 217 int ibmebus_request_irq(u32 ist, irq_handler_t handler,
 218                         unsigned long irq_flags, const char *devname,
 219                         void *dev_id)
 220 {
 221         unsigned int irq = irq_create_mapping(NULL, ist);
 222
 223         if (irq == NO_IRQ)
 224                 return -EINVAL;
 225
 226         return request_irq(irq, handler, irq_flags, devname, dev_id);
 227 }
 228 EXPORT_SYMBOL(ibmebus_request_irq);
 229
 230 void ibmebus_free_irq(u32 ist, void *dev_id)
 231 {
 232         unsigned int irq = irq_find_mapping(NULL, ist);
 233
 234         free_irq(irq, dev_id);
 235         irq_dispose_mapping(irq);
 236 }
 237 EXPORT_SYMBOL(ibmebus_free_irq);
 238
 239 static char *ibmebus_chomp(const char *in, size_t count)
 240 {
 241         char *out = kmalloc(count + 1, GFP_KERNEL);
 242
 243         if (!out)
 244                 return NULL;
 245
 246         memcpy(out, in, count);
 247         out[count] = '\0';
 248         if (out[count - 1] == '\n')
 249                 out[count - 1] = '\0';
 250
 251         return out;
 252 }
 253
 254 static ssize_t ibmebus_store_probe(struct bus_type *bus,
 255                                    const char *buf, size_t count)
 256 {
 257         struct device_node *dn = NULL;
 258         char *path;
 259         ssize_t rc = 0;
 260
 261         path = ibmebus_chomp(buf, count);
 262         if (!path)
 263                 return -ENOMEM;
 264
 265         if (bus_find_device(&ibmebus_bus_type, NULL, path,
 266                             ibmebus_match_path)) {
 267                 printk(KERN_WARNING "%s: %s has already been probed\n",
 268                        __func__, path);
 269                 rc = -EEXIST;
 270                 goto out;
 271         }
 272
 273         if ((dn = of_find_node_by_path(path))) {
 274                 rc = ibmebus_create_device(dn);
 275                 of_node_put(dn);
 276         } else {
 277                 printk(KERN_WARNING "%s: no such device node: %s\n",
 278                        __func__, path);
 279                 rc = -ENODEV;
 280         }
 281
 282 out:
 283         kfree(path);
 284         if (rc)
 285                 return rc;
 286         return count;
 287 }
 288
 289 static ssize_t ibmebus_store_remove(struct bus_type *bus,
 290                                     const char *buf, size_t count)
 291 {
 292         struct device *dev;
 293         char *path;
 294
 295         path = ibmebus_chomp(buf, count);
 296         if (!path)
 297                 return -ENOMEM;
 298
 299         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
 300                                    ibmebus_match_path))) {
 301                 of_device_unregister(to_platform_device(dev));
 302
 303                 kfree(path);
 304                 return count;
 305         } else {
 306                 printk(KERN_WARNING "%s: %s not on the bus\n",
 307                        __func__, path);
 308
 309                 kfree(path);
 310                 return -ENODEV;
 311         }
 312 }
 313
 314 static struct bus_attribute ibmebus_bus_attrs[] = {
 315         __ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe),
 316         __ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove),
 317         __ATTR_NULL
 318 };
 319
 320 struct bus_type ibmebus_bus_type = {
 321         .uevent    = of_device_uevent,
 322         .bus_attrs = ibmebus_bus_attrs
 323 };
 324 EXPORT_SYMBOL(ibmebus_bus_type);
 325
 326 static int __init ibmebus_bus_init(void)
 327 {
 328         int err;
 329
 330         printk(KERN_INFO "IBM eBus Device Driver\n");
 331
 332         err = of_bus_type_init(&ibmebus_bus_type, "ibmebus");
 333         if (err) {
 334                 printk(KERN_ERR "%s: failed to register IBM eBus.\n",
 335                        __func__);
 336                 return err;
 337         }
 338
 339         err = device_register(&ibmebus_bus_device);
 340         if (err) {
 341                 printk(KERN_WARNING "%s: device_register returned %i\n",
 342                        __func__, err);
 343                 bus_unregister(&ibmebus_bus_type);
 344
 345                 return err;
 346         }
 347
 348         err = ibmebus_create_devices(ibmebus_matches);
 349         if (err) {
 350                 device_unregister(&ibmebus_bus_device);
 351                 bus_unregister(&ibmebus_bus_type);
 352                 return err;
 353         }
 354
 355         return 0;
 356 }
 357 postcore_initcall(ibmebus_bus_init);