drivers/ieee1394/hosts.c

   1 /*
   2  * IEEE 1394 for Linux
   3  *
   4  * Low level (host adapter) management.
   5  *
   6  * Copyright (C) 1999 Andreas E. Bombe
   7  * Copyright (C) 1999 Emanuel Pirker
   8  *
   9  * This code is licensed under the GPL.  See the file COPYING in the root
  10  * directory of the kernel sources for details.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <linux/list.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <linux/timer.h>
  19 #include <linux/jiffies.h>
  20 #include <linux/mutex.h>
  21
  22 #include "csr1212.h"
  23 #include "ieee1394.h"
  24 #include "ieee1394_types.h"
  25 #include "hosts.h"
  26 #include "ieee1394_core.h"
  27 #include "highlevel.h"
  28 #include "nodemgr.h"
  29 #include "csr.h"
  30 #include "config_roms.h"
  31
  32
  33 static void delayed_reset_bus(struct work_struct *work)
  34 {
  35         struct hpsb_host *host =
  36                 container_of(work, struct hpsb_host, delayed_reset.work);
  37         int generation = host->csr.generation + 1;
  38
  39         /* The generation field rolls over to 2 rather than 0 per IEEE
  40          * 1394a-2000. */
  41         if (generation > 0xf || generation < 2)
  42                 generation = 2;
  43
  44         CSR_SET_BUS_INFO_GENERATION(host->csr.rom, generation);
  45         if (csr1212_generate_csr_image(host->csr.rom) != CSR1212_SUCCESS) {
  46                 /* CSR image creation failed.
  47                  * Reset generation field and do not issue a bus reset. */
  48                 CSR_SET_BUS_INFO_GENERATION(host->csr.rom,
  49                                             host->csr.generation);
  50                 return;
  51         }
  52
  53         host->csr.generation = generation;
  54
  55         host->update_config_rom = 0;
  56         if (host->driver->set_hw_config_rom)
  57                 host->driver->set_hw_config_rom(host,
  58                                                 host->csr.rom->bus_info_data);
  59
  60         host->csr.gen_timestamp[host->csr.generation] = jiffies;
  61         hpsb_reset_bus(host, SHORT_RESET);
  62 }
  63
  64 static int dummy_transmit_packet(struct hpsb_host *h, struct hpsb_packet *p)
  65 {
  66         return 0;
  67 }
  68
  69 static int dummy_devctl(struct hpsb_host *h, enum devctl_cmd c, int arg)
  70 {
  71         return -1;
  72 }
  73
  74 static int dummy_isoctl(struct hpsb_iso *iso, enum isoctl_cmd command,
  75                         unsigned long arg)
  76 {
  77         return -1;
  78 }
  79
  80 static struct hpsb_host_driver dummy_driver = {
  81         .transmit_packet = dummy_transmit_packet,
  82         .devctl =          dummy_devctl,
  83         .isoctl =          dummy_isoctl
  84 };
  85
  86 static int alloc_hostnum_cb(struct hpsb_host *host, void *__data)
  87 {
  88         int *hostnum = __data;
  89
  90         if (host->id == *hostnum)
  91                 return 1;
  92
  93         return 0;
  94 }
  95
  96 static DEFINE_MUTEX(host_num_alloc);
  97
  98 /**
  99  * hpsb_alloc_host - allocate a new host controller.
 100  * @drv: the driver that will manage the host controller
 101  * @extra: number of extra bytes to allocate for the driver
 102  *
 103  * Allocate a &hpsb_host and initialize the general subsystem specific
 104  * fields.  If the driver needs to store per host data, as drivers
 105  * usually do, the amount of memory required can be specified by the
 106  * @extra parameter.  Once allocated, the driver should initialize the
 107  * driver specific parts, enable the controller and make it available
 108  * to the general subsystem using hpsb_add_host().
 109  *
 110  * Return Value: a pointer to the &hpsb_host if successful, %NULL if
 111  * no memory was available.
 112  */
 113 struct hpsb_host *hpsb_alloc_host(struct hpsb_host_driver *drv, size_t extra,
 114                                   struct device *dev)
 115 {
 116         struct hpsb_host *h;
 117         int i;
 118         int hostnum = 0;
 119
 120         h = kzalloc(sizeof(*h) + extra, GFP_KERNEL);
 121         if (!h)
 122                 return NULL;
 123
 124         h->csr.rom = csr1212_create_csr(&csr_bus_ops, CSR_BUS_INFO_SIZE, h);
 125         if (!h->csr.rom)
 126                 goto fail;
 127
 128         h->hostdata = h + 1;
 129         h->driver = drv;
 130
 131         INIT_LIST_HEAD(&h->pending_packets);
 132         INIT_LIST_HEAD(&h->addr_space);
 133
 134         for (i = 2; i < 16; i++)
 135                 h->csr.gen_timestamp[i] = jiffies - 60 * HZ;
 136
 137         atomic_set(&h->generation, 0);
 138
 139         INIT_DELAYED_WORK(&h->delayed_reset, delayed_reset_bus);
 140
 141         init_timer(&h->timeout);
 142         h->timeout.data = (unsigned long) h;
 143         h->timeout.function = abort_timedouts;
 144         h->timeout_interval = HZ / 20; /* 50ms, half of minimum SPLIT_TIMEOUT */
 145
 146         h->topology_map = h->csr.topology_map + 3;
 147         h->speed_map = (u8 *)(h->csr.speed_map + 2);
 148
 149         mutex_lock(&host_num_alloc);
 150         while (nodemgr_for_each_host(&hostnum, alloc_hostnum_cb))
 151                 hostnum++;
 152         mutex_unlock(&host_num_alloc);
 153         h->id = hostnum;
 154
 155         memcpy(&h->device, &nodemgr_dev_template_host, sizeof(h->device));
 156         h->device.parent = dev;
 157         snprintf(h->device.bus_id, BUS_ID_SIZE, "fw-host%d", h->id);
 158
 159         h->class_dev.dev = &h->device;
 160         h->class_dev.class = &hpsb_host_class;
 161         snprintf(h->class_dev.class_id, BUS_ID_SIZE, "fw-host%d", h->id);
 162
 163         if (device_register(&h->device))
 164                 goto fail;
 165         if (class_device_register(&h->class_dev)) {
 166                 device_unregister(&h->device);
 167                 goto fail;
 168         }
 169         get_device(&h->device);
 170
 171         return h;
 172
 173 fail:
 174         kfree(h);
 175         return NULL;
 176 }
 177
 178 int hpsb_add_host(struct hpsb_host *host)
 179 {
 180         if (hpsb_default_host_entry(host))
 181                 return -ENOMEM;
 182
 183         highlevel_add_host(host);
 184         return 0;
 185 }
 186
 187 void hpsb_resume_host(struct hpsb_host *host)
 188 {
 189         if (host->driver->set_hw_config_rom)
 190                 host->driver->set_hw_config_rom(host,
 191                                                 host->csr.rom->bus_info_data);
 192         host->driver->devctl(host, RESET_BUS, SHORT_RESET);
 193 }
 194
 195 void hpsb_remove_host(struct hpsb_host *host)
 196 {
 197         host->is_shutdown = 1;
 198
 199         cancel_delayed_work(&host->delayed_reset);
 200         flush_scheduled_work();
 201
 202         host->driver = &dummy_driver;
 203         highlevel_remove_host(host);
 204
 205         class_device_unregister(&host->class_dev);
 206         device_unregister(&host->device);
 207 }
 208
 209 /**
 210  * hpsb_update_config_rom_image - updates configuration ROM image of a host
 211  *
 212  * Updates the configuration ROM image of a host.  rom_version must be the
 213  * current version, otherwise it will fail with return value -1. If this
 214  * host does not support config-rom-update, it will return -%EINVAL.
 215  * Return value 0 indicates success.
 216  */
 217 int hpsb_update_config_rom_image(struct hpsb_host *host)
 218 {
 219         unsigned long reset_delay;
 220         int next_gen = host->csr.generation + 1;
 221
 222         if (!host->update_config_rom)
 223                 return -EINVAL;
 224
 225         if (next_gen > 0xf)
 226                 next_gen = 2;
 227
 228         /* Stop the delayed interrupt, we're about to change the config rom and
 229          * it would be a waste to do a bus reset twice. */
 230         cancel_delayed_work(&host->delayed_reset);
 231
 232         /* IEEE 1394a-2000 prohibits using the same generation number
 233          * twice in a 60 second period. */
 234         if (time_before(jiffies, host->csr.gen_timestamp[next_gen] + 60 * HZ))
 235                 /* Wait 60 seconds from the last time this generation number was
 236                  * used. */
 237                 reset_delay =
 238                         (60 * HZ) + host->csr.gen_timestamp[next_gen] - jiffies;
 239         else
 240                 /* Wait 1 second in case some other code wants to change the
 241                  * Config ROM in the near future. */
 242                 reset_delay = HZ;
 243
 244         PREPARE_DELAYED_WORK(&host->delayed_reset, delayed_reset_bus);
 245         schedule_delayed_work(&host->delayed_reset, reset_delay);
 246
 247         return 0;
 248 }