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/config.h>
  14 #include <linux/module.h>
  15 #include <linux/types.h>
  16 #include <linux/list.h>
  17 #include <linux/init.h>
  18 #include <linux/slab.h>
  19 #include <linux/pci.h>
  20 #include <linux/timer.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(void * __reset_info)
  34 {
  35         struct hpsb_host *host = (struct hpsb_host*)__reset_info;
  36         int generation = host->csr.generation + 1;
  37
  38         /* The generation field rolls over to 2 rather than 0 per IEEE
  39          * 1394a-2000. */
  40         if (generation > 0xf || generation < 2)
  41                 generation = 2;
  42
  43         CSR_SET_BUS_INFO_GENERATION(host->csr.rom, generation);
  44         if (csr1212_generate_csr_image(host->csr.rom) != CSR1212_SUCCESS) {
  45                 /* CSR image creation failed, reset generation field and do not
  46                  * issue a bus reset. */
  47                 CSR_SET_BUS_INFO_GENERATION(host->csr.rom, host->csr.generation);
  48                 return;
  49         }
  50
  51         host->csr.generation = generation;
  52
  53         host->update_config_rom = 0;
  54         if (host->driver->set_hw_config_rom)
  55                 host->driver->set_hw_config_rom(host, host->csr.rom->bus_info_data);
  56
  57         host->csr.gen_timestamp[host->csr.generation] = jiffies;
  58         hpsb_reset_bus(host, SHORT_RESET);
  59 }
  60
  61 static int dummy_transmit_packet(struct hpsb_host *h, struct hpsb_packet *p)
  62 {
  63         return 0;
  64 }
  65
  66 static int dummy_devctl(struct hpsb_host *h, enum devctl_cmd c, int arg)
  67 {
  68         return -1;
  69 }
  70
  71 static int dummy_isoctl(struct hpsb_iso *iso, enum isoctl_cmd command, unsigned long arg)
  72 {
  73         return -1;
  74 }
  75
  76 static struct hpsb_host_driver dummy_driver = {
  77         .transmit_packet = dummy_transmit_packet,
  78         .devctl =          dummy_devctl,
  79         .isoctl =          dummy_isoctl
  80 };
  81
  82 static int alloc_hostnum_cb(struct hpsb_host *host, void *__data)
  83 {
  84         int *hostnum = __data;
  85
  86         if (host->id == *hostnum)
  87                 return 1;
  88
  89         return 0;
  90 }
  91
  92 /**
  93  * hpsb_alloc_host - allocate a new host controller.
  94  * @drv: the driver that will manage the host controller
  95  * @extra: number of extra bytes to allocate for the driver
  96  *
  97  * Allocate a &hpsb_host and initialize the general subsystem specific
  98  * fields.  If the driver needs to store per host data, as drivers
  99  * usually do, the amount of memory required can be specified by the
 100  * @extra parameter.  Once allocated, the driver should initialize the
 101  * driver specific parts, enable the controller and make it available
 102  * to the general subsystem using hpsb_add_host().
 103  *
 104  * Return Value: a pointer to the &hpsb_host if succesful, %NULL if
 105  * no memory was available.
 106  */
 107 static DECLARE_MUTEX(host_num_alloc);
 108
 109 struct hpsb_host *hpsb_alloc_host(struct hpsb_host_driver *drv, size_t extra,
 110                                   struct device *dev)
 111 {
 112         struct hpsb_host *h;
 113         int i;
 114         int hostnum = 0;
 115
 116         h = kmalloc(sizeof(struct hpsb_host) + extra, SLAB_KERNEL);
 117         if (!h) return NULL;
 118         memset(h, 0, sizeof(struct hpsb_host) + extra);
 119
 120         h->csr.rom = csr1212_create_csr(&csr_bus_ops, CSR_BUS_INFO_SIZE, h);
 121         if (!h->csr.rom) {
 122                 kfree(h);
 123                 return NULL;
 124         }
 125
 126         h->hostdata = h + 1;
 127         h->driver = drv;
 128
 129         skb_queue_head_init(&h->pending_packet_queue);
 130         INIT_LIST_HEAD(&h->addr_space);
 131
 132         for (i = 2; i < 16; i++)
 133                 h->csr.gen_timestamp[i] = jiffies - 60 * HZ;
 134
 135         for (i = 0; i < ARRAY_SIZE(h->tpool); i++)
 136                 HPSB_TPOOL_INIT(&h->tpool[i]);
 137
 138         atomic_set(&h->generation, 0);
 139
 140         INIT_WORK(&h->delayed_reset, delayed_reset_bus, h);
 141
 142         init_timer(&h->timeout);
 143         h->timeout.data = (unsigned long) h;
 144         h->timeout.function = abort_timedouts;
 145         h->timeout_interval = HZ / 20; // 50ms by default
 146
 147         h->topology_map = h->csr.topology_map + 3;
 148         h->speed_map = (u8 *)(h->csr.speed_map + 2);
 149
 150         down(&host_num_alloc);
 151
 152         while (nodemgr_for_each_host(&hostnum, alloc_hostnum_cb))
 153                 hostnum++;
 154
 155         h->id = hostnum;
 156
 157         memcpy(&h->device, &nodemgr_dev_template_host, sizeof(h->device));
 158         h->device.parent = dev;
 159         snprintf(h->device.bus_id, BUS_ID_SIZE, "fw-host%d", h->id);
 160
 161         h->class_dev.dev = &h->device;
 162         h->class_dev.class = &hpsb_host_class;
 163         snprintf(h->class_dev.class_id, BUS_ID_SIZE, "fw-host%d", h->id);
 164
 165         device_register(&h->device);
 166         class_device_register(&h->class_dev);
 167         get_device(&h->device);
 168
 169         up(&host_num_alloc);
 170
 171         return h;
 172 }
 173
 174 int hpsb_add_host(struct hpsb_host *host)
 175 {
 176         if (hpsb_default_host_entry(host))
 177                 return -ENOMEM;
 178
 179         hpsb_add_extra_config_roms(host);
 180
 181         highlevel_add_host(host);
 182
 183         return 0;
 184 }
 185
 186 void hpsb_remove_host(struct hpsb_host *host)
 187 {
 188         host->is_shutdown = 1;
 189
 190         cancel_delayed_work(&host->delayed_reset);
 191         flush_scheduled_work();
 192
 193         host->driver = &dummy_driver;
 194
 195         highlevel_remove_host(host);
 196
 197         hpsb_remove_extra_config_roms(host);
 198
 199         class_device_unregister(&host->class_dev);
 200         device_unregister(&host->device);
 201 }
 202
 203 int hpsb_update_config_rom_image(struct hpsb_host *host)
 204 {
 205         unsigned long reset_delay;
 206         int next_gen = host->csr.generation + 1;
 207
 208         if (!host->update_config_rom)
 209                 return -EINVAL;
 210
 211         if (next_gen > 0xf)
 212                 next_gen = 2;
 213
 214         /* Stop the delayed interrupt, we're about to change the config rom and
 215          * it would be a waste to do a bus reset twice. */
 216         cancel_delayed_work(&host->delayed_reset);
 217
 218         /* IEEE 1394a-2000 prohibits using the same generation number
 219          * twice in a 60 second period. */
 220         if (jiffies - host->csr.gen_timestamp[next_gen] < 60 * HZ)
 221                 /* Wait 60 seconds from the last time this generation number was
 222                  * used. */
 223                 reset_delay = (60 * HZ) + host->csr.gen_timestamp[next_gen] - jiffies;
 224         else
 225                 /* Wait 1 second in case some other code wants to change the
 226                  * Config ROM in the near future. */
 227                 reset_delay = HZ;
 228
 229         PREPARE_WORK(&host->delayed_reset, delayed_reset_bus, host);
 230         schedule_delayed_work(&host->delayed_reset, reset_delay);
 231
 232         return 0;
 233 }