linux/arch/powerpc/platforms/pseries/ibmebus.c
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   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
  51static struct device ibmebus_bus_device = { /* fake "parent" device */
  52        .init_name = "ibmebus",
  53};
  54
  55struct bus_type ibmebus_bus_type;
  56
  57/* These devices will automatically be added to the bus during init */
  58static const struct of_device_id ibmebus_matches[] __initconst = {
  59        { .compatible = "IBM,lhca" },
  60        { .compatible = "IBM,lhea" },
  61        {},
  62};
  63
  64static 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
  78static 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
  86static 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
  96static 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
 105static 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
 121static 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
 129static int ibmebus_dma_supported(struct device *dev, u64 mask)
 130{
 131        return mask == DMA_BIT_MASK(64);
 132}
 133
 134static u64 ibmebus_dma_get_required_mask(struct device *dev)
 135{
 136        return DMA_BIT_MASK(64);
 137}
 138
 139static 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
 150static int ibmebus_match_path(struct device *dev, void *data)
 151{
 152        struct device_node *dn = to_platform_device(dev)->dev.of_node;
 153        return (of_find_node_by_path(data) == dn);
 154}
 155
 156static int ibmebus_match_node(struct device *dev, void *data)
 157{
 158        return to_platform_device(dev)->dev.of_node == data;
 159}
 160
 161static int ibmebus_create_device(struct device_node *dn)
 162{
 163        struct platform_device *dev;
 164        int ret;
 165
 166        dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
 167        if (!dev)
 168                return -ENOMEM;
 169
 170        dev->dev.bus = &ibmebus_bus_type;
 171        dev->dev.dma_ops = &ibmebus_dma_ops;
 172
 173        ret = of_device_add(dev);
 174        if (ret)
 175                platform_device_put(dev);
 176        return ret;
 177}
 178
 179static int ibmebus_create_devices(const struct of_device_id *matches)
 180{
 181        struct device_node *root, *child;
 182        struct device *dev;
 183        int ret = 0;
 184
 185        root = of_find_node_by_path("/");
 186
 187        for_each_child_of_node(root, child) {
 188                if (!of_match_node(matches, child))
 189                        continue;
 190
 191                dev = bus_find_device(&ibmebus_bus_type, NULL, child,
 192                                      ibmebus_match_node);
 193                if (dev) {
 194                        put_device(dev);
 195                        continue;
 196                }
 197
 198                ret = ibmebus_create_device(child);
 199                if (ret) {
 200                        printk(KERN_ERR "%s: failed to create device (%i)",
 201                               __func__, ret);
 202                        of_node_put(child);
 203                        break;
 204                }
 205        }
 206
 207        of_node_put(root);
 208        return ret;
 209}
 210
 211int ibmebus_register_driver(struct platform_driver *drv)
 212{
 213        /* If the driver uses devices that ibmebus doesn't know, add them */
 214        ibmebus_create_devices(drv->driver.of_match_table);
 215
 216        drv->driver.bus = &ibmebus_bus_type;
 217        return driver_register(&drv->driver);
 218}
 219EXPORT_SYMBOL(ibmebus_register_driver);
 220
 221void ibmebus_unregister_driver(struct platform_driver *drv)
 222{
 223        driver_unregister(&drv->driver);
 224}
 225EXPORT_SYMBOL(ibmebus_unregister_driver);
 226
 227int ibmebus_request_irq(u32 ist, irq_handler_t handler,
 228                        unsigned long irq_flags, const char *devname,
 229                        void *dev_id)
 230{
 231        unsigned int irq = irq_create_mapping(NULL, ist);
 232
 233        if (!irq)
 234                return -EINVAL;
 235
 236        return request_irq(irq, handler, irq_flags, devname, dev_id);
 237}
 238EXPORT_SYMBOL(ibmebus_request_irq);
 239
 240void ibmebus_free_irq(u32 ist, void *dev_id)
 241{
 242        unsigned int irq = irq_find_mapping(NULL, ist);
 243
 244        free_irq(irq, dev_id);
 245        irq_dispose_mapping(irq);
 246}
 247EXPORT_SYMBOL(ibmebus_free_irq);
 248
 249static char *ibmebus_chomp(const char *in, size_t count)
 250{
 251        char *out = kmalloc(count + 1, GFP_KERNEL);
 252
 253        if (!out)
 254                return NULL;
 255
 256        memcpy(out, in, count);
 257        out[count] = '\0';
 258        if (out[count - 1] == '\n')
 259                out[count - 1] = '\0';
 260
 261        return out;
 262}
 263
 264static ssize_t ibmebus_store_probe(struct bus_type *bus,
 265                                   const char *buf, size_t count)
 266{
 267        struct device_node *dn = NULL;
 268        struct device *dev;
 269        char *path;
 270        ssize_t rc = 0;
 271
 272        path = ibmebus_chomp(buf, count);
 273        if (!path)
 274                return -ENOMEM;
 275
 276        dev = bus_find_device(&ibmebus_bus_type, NULL, path,
 277                              ibmebus_match_path);
 278        if (dev) {
 279                put_device(dev);
 280                printk(KERN_WARNING "%s: %s has already been probed\n",
 281                       __func__, path);
 282                rc = -EEXIST;
 283                goto out;
 284        }
 285
 286        if ((dn = of_find_node_by_path(path))) {
 287                rc = ibmebus_create_device(dn);
 288                of_node_put(dn);
 289        } else {
 290                printk(KERN_WARNING "%s: no such device node: %s\n",
 291                       __func__, path);
 292                rc = -ENODEV;
 293        }
 294
 295out:
 296        kfree(path);
 297        if (rc)
 298                return rc;
 299        return count;
 300}
 301static BUS_ATTR(probe, 0200, NULL, ibmebus_store_probe);
 302
 303static ssize_t ibmebus_store_remove(struct bus_type *bus,
 304                                    const char *buf, size_t count)
 305{
 306        struct device *dev;
 307        char *path;
 308
 309        path = ibmebus_chomp(buf, count);
 310        if (!path)
 311                return -ENOMEM;
 312
 313        if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
 314                                   ibmebus_match_path))) {
 315                of_device_unregister(to_platform_device(dev));
 316                put_device(dev);
 317
 318                kfree(path);
 319                return count;
 320        } else {
 321                printk(KERN_WARNING "%s: %s not on the bus\n",
 322                       __func__, path);
 323
 324                kfree(path);
 325                return -ENODEV;
 326        }
 327}
 328static BUS_ATTR(remove, 0200, NULL, ibmebus_store_remove);
 329
 330static struct attribute *ibmbus_bus_attrs[] = {
 331        &bus_attr_probe.attr,
 332        &bus_attr_remove.attr,
 333        NULL,
 334};
 335ATTRIBUTE_GROUPS(ibmbus_bus);
 336
 337static int ibmebus_bus_bus_match(struct device *dev, struct device_driver *drv)
 338{
 339        const struct of_device_id *matches = drv->of_match_table;
 340
 341        if (!matches)
 342                return 0;
 343
 344        return of_match_device(matches, dev) != NULL;
 345}
 346
 347static int ibmebus_bus_device_probe(struct device *dev)
 348{
 349        int error = -ENODEV;
 350        struct platform_driver *drv;
 351        struct platform_device *of_dev;
 352
 353        drv = to_platform_driver(dev->driver);
 354        of_dev = to_platform_device(dev);
 355
 356        if (!drv->probe)
 357                return error;
 358
 359        of_dev_get(of_dev);
 360
 361        if (of_driver_match_device(dev, dev->driver))
 362                error = drv->probe(of_dev);
 363        if (error)
 364                of_dev_put(of_dev);
 365
 366        return error;
 367}
 368
 369static int ibmebus_bus_device_remove(struct device *dev)
 370{
 371        struct platform_device *of_dev = to_platform_device(dev);
 372        struct platform_driver *drv = to_platform_driver(dev->driver);
 373
 374        if (dev->driver && drv->remove)
 375                drv->remove(of_dev);
 376        return 0;
 377}
 378
 379static void ibmebus_bus_device_shutdown(struct device *dev)
 380{
 381        struct platform_device *of_dev = to_platform_device(dev);
 382        struct platform_driver *drv = to_platform_driver(dev->driver);
 383
 384        if (dev->driver && drv->shutdown)
 385                drv->shutdown(of_dev);
 386}
 387
 388/*
 389 * ibmebus_bus_device_attrs
 390 */
 391static ssize_t devspec_show(struct device *dev,
 392                                struct device_attribute *attr, char *buf)
 393{
 394        struct platform_device *ofdev;
 395
 396        ofdev = to_platform_device(dev);
 397        return sprintf(buf, "%pOF\n", ofdev->dev.of_node);
 398}
 399static DEVICE_ATTR_RO(devspec);
 400
 401static 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}
 409static DEVICE_ATTR_RO(name);
 410
 411static ssize_t modalias_show(struct device *dev,
 412                                struct device_attribute *attr, char *buf)
 413{
 414        return of_device_modalias(dev, buf, PAGE_SIZE);
 415}
 416static DEVICE_ATTR_RO(modalias);
 417
 418static struct attribute *ibmebus_bus_device_attrs[] = {
 419        &dev_attr_devspec.attr,
 420        &dev_attr_name.attr,
 421        &dev_attr_modalias.attr,
 422        NULL,
 423};
 424ATTRIBUTE_GROUPS(ibmebus_bus_device);
 425
 426struct bus_type ibmebus_bus_type = {
 427        .name      = "ibmebus",
 428        .uevent    = of_device_uevent_modalias,
 429        .bus_groups = ibmbus_bus_groups,
 430        .match     = ibmebus_bus_bus_match,
 431        .probe     = ibmebus_bus_device_probe,
 432        .remove    = ibmebus_bus_device_remove,
 433        .shutdown  = ibmebus_bus_device_shutdown,
 434        .dev_groups = ibmebus_bus_device_groups,
 435};
 436EXPORT_SYMBOL(ibmebus_bus_type);
 437
 438static int __init ibmebus_bus_init(void)
 439{
 440        int err;
 441
 442        printk(KERN_INFO "IBM eBus Device Driver\n");
 443
 444        err = bus_register(&ibmebus_bus_type);
 445        if (err) {
 446                printk(KERN_ERR "%s: failed to register IBM eBus.\n",
 447                       __func__);
 448                return err;
 449        }
 450
 451        err = device_register(&ibmebus_bus_device);
 452        if (err) {
 453                printk(KERN_WARNING "%s: device_register returned %i\n",
 454                       __func__, err);
 455                bus_unregister(&ibmebus_bus_type);
 456
 457                return err;
 458        }
 459
 460        err = ibmebus_create_devices(ibmebus_matches);
 461        if (err) {
 462                device_unregister(&ibmebus_bus_device);
 463                bus_unregister(&ibmebus_bus_type);
 464                return err;
 465        }
 466
 467        return 0;
 468}
 469postcore_initcall(ibmebus_bus_init);
 470