drivers/ieee1394/iso.c

   1 /*
   2  * IEEE 1394 for Linux
   3  *
   4  * kernel ISO transmission/reception
   5  *
   6  * Copyright (C) 2002 Maas Digital LLC
   7  *
   8  * This code is licensed under the GPL.  See the file COPYING in the root
   9  * directory of the kernel sources for details.
  10  */
  11
  12 #include <linux/slab.h>
  13 #include <linux/sched.h>
  14 #include "iso.h"
  15
  16 void hpsb_iso_stop(struct hpsb_iso *iso)
  17 {
  18         if (!(iso->flags & HPSB_ISO_DRIVER_STARTED))
  19                 return;
  20
  21         iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?
  22                                   XMIT_STOP : RECV_STOP, 0);
  23         iso->flags &= ~HPSB_ISO_DRIVER_STARTED;
  24 }
  25
  26 void hpsb_iso_shutdown(struct hpsb_iso *iso)
  27 {
  28         if (iso->flags & HPSB_ISO_DRIVER_INIT) {
  29                 hpsb_iso_stop(iso);
  30                 iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?
  31                                           XMIT_SHUTDOWN : RECV_SHUTDOWN, 0);
  32                 iso->flags &= ~HPSB_ISO_DRIVER_INIT;
  33         }
  34
  35         dma_region_free(&iso->data_buf);
  36         kfree(iso);
  37 }
  38
  39 static struct hpsb_iso* hpsb_iso_common_init(struct hpsb_host *host, enum hpsb_iso_type type,
  40                                              unsigned int data_buf_size,
  41                                              unsigned int buf_packets,
  42                                              int channel,
  43                                              int dma_mode,
  44                                              int irq_interval,
  45                                              void (*callback)(struct hpsb_iso*))
  46 {
  47         struct hpsb_iso *iso;
  48         int dma_direction;
  49
  50         /* make sure driver supports the ISO API */
  51         if (!host->driver->isoctl) {
  52                 printk(KERN_INFO "ieee1394: host driver '%s' does not support the rawiso API\n",
  53                        host->driver->name);
  54                 return NULL;
  55         }
  56
  57         /* sanitize parameters */
  58
  59         if (buf_packets < 2)
  60                 buf_packets = 2;
  61
  62         if ((dma_mode < HPSB_ISO_DMA_DEFAULT) || (dma_mode > HPSB_ISO_DMA_PACKET_PER_BUFFER))
  63                 dma_mode=HPSB_ISO_DMA_DEFAULT;
  64
  65         if (irq_interval == 0)     /* really interrupt for each packet*/
  66                 irq_interval = 1;
  67         else if ((irq_interval < 0) || (irq_interval > buf_packets / 4))
  68                 irq_interval = buf_packets / 4;
  69
  70         if (channel < -1 || channel >= 64)
  71                 return NULL;
  72
  73         /* channel = -1 is OK for multi-channel recv but not for xmit */
  74         if (type == HPSB_ISO_XMIT && channel < 0)
  75                 return NULL;
  76
  77         /* allocate and write the struct hpsb_iso */
  78
  79         iso = kmalloc(sizeof(*iso) + buf_packets * sizeof(struct hpsb_iso_packet_info), GFP_KERNEL);
  80         if (!iso)
  81                 return NULL;
  82
  83         iso->infos = (struct hpsb_iso_packet_info *)(iso + 1);
  84
  85         iso->type = type;
  86         iso->host = host;
  87         iso->hostdata = NULL;
  88         iso->callback = callback;
  89         init_waitqueue_head(&iso->waitq);
  90         iso->channel = channel;
  91         iso->irq_interval = irq_interval;
  92         iso->dma_mode = dma_mode;
  93         dma_region_init(&iso->data_buf);
  94         iso->buf_size = PAGE_ALIGN(data_buf_size);
  95         iso->buf_packets = buf_packets;
  96         iso->pkt_dma = 0;
  97         iso->first_packet = 0;
  98         spin_lock_init(&iso->lock);
  99
 100         if (iso->type == HPSB_ISO_XMIT) {
 101                 iso->n_ready_packets = iso->buf_packets;
 102                 dma_direction = PCI_DMA_TODEVICE;
 103         } else {
 104                 iso->n_ready_packets = 0;
 105                 dma_direction = PCI_DMA_FROMDEVICE;
 106         }
 107
 108         atomic_set(&iso->overflows, 0);
 109         iso->flags = 0;
 110         iso->prebuffer = 0;
 111
 112         /* allocate the packet buffer */
 113         if (dma_region_alloc(&iso->data_buf, iso->buf_size, host->pdev, dma_direction))
 114                 goto err;
 115
 116         return iso;
 117
 118 err:
 119         hpsb_iso_shutdown(iso);
 120         return NULL;
 121 }
 122
 123 int hpsb_iso_n_ready(struct hpsb_iso* iso)
 124 {
 125         unsigned long flags;
 126         int val;
 127
 128         spin_lock_irqsave(&iso->lock, flags);
 129         val = iso->n_ready_packets;
 130         spin_unlock_irqrestore(&iso->lock, flags);
 131
 132         return val;
 133 }
 134
 135
 136 struct hpsb_iso* hpsb_iso_xmit_init(struct hpsb_host *host,
 137                                     unsigned int data_buf_size,
 138                                     unsigned int buf_packets,
 139                                     int channel,
 140                                     int speed,
 141                                     int irq_interval,
 142                                     void (*callback)(struct hpsb_iso*))
 143 {
 144         struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_XMIT,
 145                                                     data_buf_size, buf_packets,
 146                                                     channel, HPSB_ISO_DMA_DEFAULT, irq_interval, callback);
 147         if (!iso)
 148                 return NULL;
 149
 150         iso->speed = speed;
 151
 152         /* tell the driver to start working */
 153         if (host->driver->isoctl(iso, XMIT_INIT, 0))
 154                 goto err;
 155
 156         iso->flags |= HPSB_ISO_DRIVER_INIT;
 157         return iso;
 158
 159 err:
 160         hpsb_iso_shutdown(iso);
 161         return NULL;
 162 }
 163
 164 struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host,
 165                                     unsigned int data_buf_size,
 166                                     unsigned int buf_packets,
 167                                     int channel,
 168                                     int dma_mode,
 169                                     int irq_interval,
 170                                     void (*callback)(struct hpsb_iso*))
 171 {
 172         struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_RECV,
 173                                                     data_buf_size, buf_packets,
 174                                                     channel, dma_mode, irq_interval, callback);
 175         if (!iso)
 176                 return NULL;
 177
 178         /* tell the driver to start working */
 179         if (host->driver->isoctl(iso, RECV_INIT, 0))
 180                 goto err;
 181
 182         iso->flags |= HPSB_ISO_DRIVER_INIT;
 183         return iso;
 184
 185 err:
 186         hpsb_iso_shutdown(iso);
 187         return NULL;
 188 }
 189
 190 int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel)
 191 {
 192         if (iso->type != HPSB_ISO_RECV || iso->channel != -1 || channel >= 64)
 193                 return -EINVAL;
 194         return iso->host->driver->isoctl(iso, RECV_LISTEN_CHANNEL, channel);
 195 }
 196
 197 int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel)
 198 {
 199        if (iso->type != HPSB_ISO_RECV || iso->channel != -1 || channel >= 64)
 200                return -EINVAL;
 201        return iso->host->driver->isoctl(iso, RECV_UNLISTEN_CHANNEL, channel);
 202 }
 203
 204 int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask)
 205 {
 206         if (iso->type != HPSB_ISO_RECV || iso->channel != -1)
 207                 return -EINVAL;
 208         return iso->host->driver->isoctl(iso, RECV_SET_CHANNEL_MASK, (unsigned long) &mask);
 209 }
 210
 211 int hpsb_iso_recv_flush(struct hpsb_iso *iso)
 212 {
 213         if (iso->type != HPSB_ISO_RECV)
 214                 return -EINVAL;
 215         return iso->host->driver->isoctl(iso, RECV_FLUSH, 0);
 216 }
 217
 218 static int do_iso_xmit_start(struct hpsb_iso *iso, int cycle)
 219 {
 220         int retval = iso->host->driver->isoctl(iso, XMIT_START, cycle);
 221         if (retval)
 222                 return retval;
 223
 224         iso->flags |= HPSB_ISO_DRIVER_STARTED;
 225         return retval;
 226 }
 227
 228 int hpsb_iso_xmit_start(struct hpsb_iso *iso, int cycle, int prebuffer)
 229 {
 230         if (iso->type != HPSB_ISO_XMIT)
 231                 return -1;
 232
 233         if (iso->flags & HPSB_ISO_DRIVER_STARTED)
 234                 return 0;
 235
 236         if (cycle < -1)
 237                 cycle = -1;
 238         else if (cycle >= 8000)
 239                 cycle %= 8000;
 240
 241         iso->xmit_cycle = cycle;
 242
 243         if (prebuffer < 0)
 244                 prebuffer = iso->buf_packets;
 245         else if (prebuffer == 0)
 246                 prebuffer = 1;
 247
 248         if (prebuffer > iso->buf_packets)
 249                 prebuffer = iso->buf_packets;
 250
 251         iso->prebuffer = prebuffer;
 252
 253         /* remember the starting cycle; DMA will commence from xmit_queue_packets()
 254            once enough packets have been buffered */
 255         iso->start_cycle = cycle;
 256
 257         return 0;
 258 }
 259
 260 int hpsb_iso_recv_start(struct hpsb_iso *iso, int cycle, int tag_mask, int sync)
 261 {
 262         int retval = 0;
 263         int isoctl_args[3];
 264
 265         if (iso->type != HPSB_ISO_RECV)
 266                 return -1;
 267
 268         if (iso->flags & HPSB_ISO_DRIVER_STARTED)
 269                 return 0;
 270
 271         if (cycle < -1)
 272                 cycle = -1;
 273         else if (cycle >= 8000)
 274                 cycle %= 8000;
 275
 276         isoctl_args[0] = cycle;
 277
 278         if (tag_mask < 0)
 279                 /* match all tags */
 280                 tag_mask = 0xF;
 281         isoctl_args[1] = tag_mask;
 282
 283         isoctl_args[2] = sync;
 284
 285         retval = iso->host->driver->isoctl(iso, RECV_START, (unsigned long) &isoctl_args[0]);
 286         if (retval)
 287                 return retval;
 288
 289         iso->flags |= HPSB_ISO_DRIVER_STARTED;
 290         return retval;
 291 }
 292
 293 /* check to make sure the user has not supplied bogus values of offset/len
 294    that would cause the kernel to access memory outside the buffer */
 295
 296 static int hpsb_iso_check_offset_len(struct hpsb_iso *iso,
 297                                      unsigned int offset, unsigned short len,
 298                                      unsigned int *out_offset, unsigned short *out_len)
 299 {
 300         if (offset >= iso->buf_size)
 301                 return -EFAULT;
 302
 303         /* make sure the packet does not go beyond the end of the buffer */
 304         if (offset + len > iso->buf_size)
 305                 return -EFAULT;
 306
 307         /* check for wrap-around */
 308         if (offset + len < offset)
 309                 return -EFAULT;
 310
 311         /* now we can trust 'offset' and 'length' */
 312         *out_offset = offset;
 313         *out_len = len;
 314
 315         return 0;
 316 }
 317
 318
 319 int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len, u8 tag, u8 sy)
 320 {
 321         struct hpsb_iso_packet_info *info;
 322         unsigned long flags;
 323         int rv;
 324
 325         if (iso->type != HPSB_ISO_XMIT)
 326                 return -EINVAL;
 327
 328         /* is there space in the buffer? */
 329         if (iso->n_ready_packets <= 0) {
 330                 return -EBUSY;
 331         }
 332
 333         info = &iso->infos[iso->first_packet];
 334
 335         /* check for bogus offset/length */
 336         if (hpsb_iso_check_offset_len(iso, offset, len, &info->offset, &info->len))
 337                 return -EFAULT;
 338
 339         info->tag = tag;
 340         info->sy = sy;
 341
 342         spin_lock_irqsave(&iso->lock, flags);
 343
 344         rv = iso->host->driver->isoctl(iso, XMIT_QUEUE, (unsigned long) info);
 345         if (rv)
 346                 goto out;
 347
 348         /* increment cursors */
 349         iso->first_packet = (iso->first_packet+1) % iso->buf_packets;
 350         iso->xmit_cycle = (iso->xmit_cycle+1) % 8000;
 351         iso->n_ready_packets--;
 352
 353         if (iso->prebuffer != 0) {
 354                 iso->prebuffer--;
 355                 if (iso->prebuffer <= 0) {
 356                         iso->prebuffer = 0;
 357                         rv = do_iso_xmit_start(iso, iso->start_cycle);
 358                 }
 359         }
 360
 361 out:
 362         spin_unlock_irqrestore(&iso->lock, flags);
 363         return rv;
 364 }
 365
 366 int hpsb_iso_xmit_sync(struct hpsb_iso *iso)
 367 {
 368         if (iso->type != HPSB_ISO_XMIT)
 369                 return -EINVAL;
 370
 371         return wait_event_interruptible(iso->waitq, hpsb_iso_n_ready(iso) == iso->buf_packets);
 372 }
 373
 374 void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error)
 375 {
 376         unsigned long flags;
 377         spin_lock_irqsave(&iso->lock, flags);
 378
 379         /* predict the cycle of the next packet to be queued */
 380
 381         /* jump ahead by the number of packets that are already buffered */
 382         cycle += iso->buf_packets - iso->n_ready_packets;
 383         cycle %= 8000;
 384
 385         iso->xmit_cycle = cycle;
 386         iso->n_ready_packets++;
 387         iso->pkt_dma = (iso->pkt_dma + 1) % iso->buf_packets;
 388
 389         if (iso->n_ready_packets == iso->buf_packets || error != 0) {
 390                 /* the buffer has run empty! */
 391                 atomic_inc(&iso->overflows);
 392         }
 393
 394         spin_unlock_irqrestore(&iso->lock, flags);
 395 }
 396
 397 void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,
 398                               u16 cycle, u8 channel, u8 tag, u8 sy)
 399 {
 400         unsigned long flags;
 401         spin_lock_irqsave(&iso->lock, flags);
 402
 403         if (iso->n_ready_packets == iso->buf_packets) {
 404                 /* overflow! */
 405                 atomic_inc(&iso->overflows);
 406         } else {
 407                 struct hpsb_iso_packet_info *info = &iso->infos[iso->pkt_dma];
 408                 info->offset = offset;
 409                 info->len = len;
 410                 info->cycle = cycle;
 411                 info->channel = channel;
 412                 info->tag = tag;
 413                 info->sy = sy;
 414
 415                 iso->pkt_dma = (iso->pkt_dma+1) % iso->buf_packets;
 416                 iso->n_ready_packets++;
 417         }
 418
 419         spin_unlock_irqrestore(&iso->lock, flags);
 420 }
 421
 422 int hpsb_iso_recv_release_packets(struct hpsb_iso *iso, unsigned int n_packets)
 423 {
 424         unsigned long flags;
 425         unsigned int i;
 426         int rv = 0;
 427
 428         if (iso->type != HPSB_ISO_RECV)
 429                 return -1;
 430
 431         spin_lock_irqsave(&iso->lock, flags);
 432         for (i = 0; i < n_packets; i++) {
 433                 rv = iso->host->driver->isoctl(iso, RECV_RELEASE,
 434                                                (unsigned long) &iso->infos[iso->first_packet]);
 435                 if (rv)
 436                         break;
 437
 438                 iso->first_packet = (iso->first_packet+1) % iso->buf_packets;
 439                 iso->n_ready_packets--;
 440         }
 441         spin_unlock_irqrestore(&iso->lock, flags);
 442         return rv;
 443 }
 444
 445 void hpsb_iso_wake(struct hpsb_iso *iso)
 446 {
 447         wake_up_interruptible(&iso->waitq);
 448
 449         if (iso->callback)
 450                 iso->callback(iso);
 451 }