microdia-buf.c

   1 /**
   2  * @file microdia-buf.c
   3  * @author Nicolas VIVIEN
   4  * @date 2008-02-01
   5  * @version v0.0.0
   6  *
   7  * @brief Driver for Microdia USB video camera
   8  *
   9  * @note Copyright (C) Nicolas VIVIEN
  10  *
  11  * @par Licences
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  26  *
  27  * @par SubVersion
  28  *   $Date: 2007-12-08 11:34:45 +0100 (sam, 08 déc 2007) $
  29  *   $Revision: 68 $
  30  *   $Author: nicklas79 $
  31  *   $HeadURL: https://syntekdriver.svn.sourceforge.net/svnroot/syntekdriver/trunk/driver/microdia-buf.c $
  32  */
  33
  34 #include <linux/module.h>
  35 #include <linux/init.h>
  36 #include <linux/kernel.h>
  37 #include <linux/version.h>
  38 #include <linux/errno.h>
  39 #include <linux/slab.h>
  40 #include <linux/kref.h>
  41 #include <linux/vmalloc.h>
  42
  43 #include <linux/usb.h>
  44 #include <media/v4l2-common.h>
  45
  46 #include "microdia.h"
  47
  48
  49 /**
  50  * @var default_nbrframebuf
  51  *   Number of frame buffer by default
  52  */
  53 static int default_nbrframebuf = 3;
  54
  55
  56 /**
  57  * @param size Size of memory
  58  *
  59  * @returns Address on the allocated memory
  60  *
  61  * @brief Allocate a buffer.
  62  *
  63  * This function permits to allocate a buffer in memory.
  64  */
  65 void * microdia_rvmalloc(unsigned long size)
  66 {
  67         void *mem;
  68         unsigned long addr;
  69
  70         size = PAGE_ALIGN(size);
  71         mem = vmalloc_32(size);
  72
  73         if (!mem)
  74                 return NULL;
  75
  76         memset(mem, 0, size);
  77
  78         addr = (unsigned long) mem;
  79
  80         while (size > 0) {
  81                 SetPageReserved(vmalloc_to_page((void *) addr));
  82                 addr += PAGE_SIZE;
  83                 size -= PAGE_SIZE;
  84         }
  85
  86         return mem;
  87 }
  88
  89
  90 /**
  91  * @param mem Memory address
  92  * @param size Size of allocated memory
  93  *
  94  * @brief Free a buffer
  95  *
  96  * This function permits to free a buffer.
  97  */
  98 void microdia_rvfree(void *mem, unsigned long size)
  99 {
 100         unsigned long addr;
 101
 102         if (!mem)
 103                 return;
 104
 105         addr = (unsigned long) mem;
 106
 107         while ((long) size > 0) {
 108                 ClearPageReserved(vmalloc_to_page((void *) addr));
 109                 addr += PAGE_SIZE;
 110                 size -= PAGE_SIZE;
 111         }
 112
 113         vfree(mem);
 114 }
 115
 116
 117 /**
 118  * @param dev Device structure
 119  *
 120  * @returns 0 if all is OK
 121  *
 122  * @brief Allocate all ISOC buffers.
 123  *
 124  * This function permits to reserved the memory for each ISOC buffer.
 125  */
 126 int microdia_allocate_buffers(struct usb_microdia *dev)
 127 {
 128         int i;
 129         void *kbuf;
 130         __u16 iso_max_frame_size;
 131
 132         UDIA_DEBUG("Allocate video buffers\n");
 133
 134         if (dev == NULL)
 135                 return -ENXIO;
 136
 137         // iso_max_frame_size should be the endpoints maximum packetsize * the highbandwidth multiplier.
 138
 139         iso_max_frame_size = max_packet_sz(le16_to_cpu(dev->isoc_in_size)) * hb_multiplier(le16_to_cpu(dev->isoc_in_size));
 140
 141         // Allocate isochronous pipe buffers
 142         for (i=0; i<MAX_ISO_BUFS; i++) {
 143                 if (dev->isobuf[i].data == NULL) {
 144         kbuf = kzalloc(iso_max_frame_size * ISO_FRAMES_PER_DESC, GFP_KERNEL);
 145
 146                         if (kbuf == NULL) {
 147                                 UDIA_ERROR("Failed to allocate iso buffer %d\n", i);
 148                                 return -ENOMEM;
 149                         }
 150
 151                         UDIA_DEBUG("Allocated iso buffer at %p\n", kbuf);
 152
 153                         dev->isobuf[i].data = kbuf;
 154                 }
 155         }
 156
 157         // Allocate frame buffer structure
 158         if (dev->framebuf == NULL) {
 159                 kbuf = kzalloc(default_nbrframebuf * sizeof(struct microdia_frame_buf), GFP_KERNEL);
 160
 161                 if (kbuf == NULL) {
 162                         UDIA_ERROR("Failed to allocate frame buffer structure\n");
 163                         return -ENOMEM;
 164                 }
 165
 166                 UDIA_DEBUG("Allocated frame buffer structure at %p\n", kbuf);
 167
 168                 dev->framebuf = kbuf;
 169         }
 170
 171         // Create frame buffers and make circular ring
 172         for (i=0; i<default_nbrframebuf; i++) {
 173                 if (dev->framebuf[i].data == NULL) {
 174                         kbuf = vmalloc(MICRODIA_FRAME_SIZE);
 175
 176                         if (kbuf == NULL) {
 177                                 UDIA_ERROR("Failed to allocate frame buffer %d\n", i);
 178                                 return -ENOMEM;
 179                         }
 180
 181                         UDIA_DEBUG("Allocated frame buffer %d at %p.\n", i, kbuf);
 182
 183                         dev->framebuf[i].data = kbuf;
 184                         memset(kbuf, 0, MICRODIA_FRAME_SIZE);
 185                 }
 186         }
 187
 188         // Allocate image buffer; double buffer for mmap()
 189         kbuf = microdia_rvmalloc(dev->nbuffers * dev->len_per_image);
 190
 191         if (kbuf == NULL) {
 192                 UDIA_ERROR("Failed to allocate image buffer(s). needed (%d)\n",
 193                                 dev->nbuffers * dev->len_per_image);
 194                 return -ENOMEM;
 195         }
 196
 197         UDIA_DEBUG("Allocated image buffer at %p\n", kbuf);
 198
 199         dev->image_data = kbuf;
 200
 201         for (i = 0; i < dev->nbuffers; i++) {
 202                 dev->images[i].offset = i * dev->len_per_image;
 203                 dev->images[i].vma_use_count = 0;
 204         }
 205
 206         for (; i < MICRODIA_MAX_IMAGES; i++)
 207                 dev->images[i].offset = 0;
 208
 209         kbuf = NULL;
 210
 211         return 0;
 212 }
 213
 214
 215 /**
 216  * @param dev Device structure
 217  *
 218  * @returns 0 if all is OK
 219  *
 220  * @brief Reset all ISOC buffers.
 221  *
 222  * This function permits to reset all ISOC buffers.
 223  */
 224 int microdia_reset_buffers(struct usb_microdia *dev)
 225 {
 226         int i;
 227         unsigned long flags;
 228
 229         UDIA_DEBUG("Reset all buffers\n");
 230
 231         spin_lock_irqsave(&dev->spinlock, flags);
 232
 233         dev->full_frames = NULL;
 234         dev->full_frames_tail = NULL;
 235
 236         for (i=0; i<dev->nbuffers; i++) {
 237                 dev->framebuf[i].filled = 0;
 238                 dev->framebuf[i].errors = 0;
 239
 240                 if (i > 0)
 241                         dev->framebuf[i].next = &dev->framebuf[i - 1];
 242                 else
 243                         dev->framebuf->next = NULL;
 244         }
 245
 246         dev->empty_frames = &dev->framebuf[dev->nbuffers - 1];
 247         dev->empty_frames_tail = dev->framebuf;
 248         dev->read_frame = NULL;
 249         dev->fill_frame = dev->empty_frames;
 250         dev->empty_frames = dev->empty_frames->next;
 251
 252         dev->image_read_pos = 0;
 253         dev->fill_image = 0;
 254
 255         spin_unlock_irqrestore(&dev->spinlock, flags);
 256
 257         for (i=0; i<dev->nbuffers; i++)
 258                 dev->image_used[i] = 0;
 259
 260         return 0;
 261 }
 262
 263
 264 /**
 265  * @param dev Device structure
 266  *
 267  * @returns 0 if all is OK
 268  *
 269  * @brief Clear current buffers.
 270  *
 271  * This function permits to clear the memory.
 272  */
 273 int microdia_clear_buffers(struct usb_microdia *dev)
 274 {
 275         memset(dev->image_data, 0x00, dev->nbuffers * dev->len_per_image);
 276
 277         return 0;
 278 }
 279
 280
 281 /**
 282  * @param dev Device structure
 283  *
 284  * @returns 0 if all is OK
 285  *
 286  * @brief Release all buffers.
 287  *
 288  * This function permits to release and free the memory for each ISOC buffer.
 289  */
 290 int microdia_free_buffers(struct usb_microdia *dev)
 291 {
 292         int i;
 293
 294         UDIA_DEBUG("Free buffers\n");
 295
 296         if (dev == NULL)
 297                 return -1;
 298
 299         // Release iso pipe buffers
 300         for (i=0; i<MAX_ISO_BUFS; i++) {
 301                 if (dev->isobuf[i].data != NULL) {
 302                         kfree(dev->isobuf[i].data);
 303                         dev->isobuf[i].data = NULL;
 304                 }
 305         }
 306
 307         // Release frame buffers
 308         if (dev->framebuf != NULL) {
 309                 for (i=0; i<default_nbrframebuf; i++) {
 310                         if (dev->framebuf[i].data != NULL) {
 311                                 vfree(dev->framebuf[i].data);
 312                                 dev->framebuf[i].data = NULL;
 313                         }
 314                 }
 315
 316                 kfree(dev->framebuf);
 317                 dev->framebuf = NULL;
 318         }
 319
 320         // Release image buffers
 321         if (dev->image_data != NULL)
 322                 microdia_rvfree(dev->image_data, dev->nbuffers * dev->len_per_image);
 323
 324         dev->image_data = NULL;
 325
 326         return 0;
 327 }
 328
 329
 330 /**
 331  * @param dev Device structure
 332  *
 333  * @brief Prepare the next image.
 334  *
 335  * This function is called when an image is ready, so as to prepare the next image.
 336  */
 337 void microdia_next_image(struct usb_microdia *dev)
 338 {
 339         UDIA_STREAM("Select next image\n");
 340
 341         dev->image_used[dev->fill_image] = 0;
 342         dev->fill_image = (dev->fill_image + 1) % dev->nbuffers;
 343 }
 344
 345
 346 /**
 347  * @param dev Device structure
 348  *
 349  * @returns 0 if all is OK
 350  *
 351  * @brief Prepare the next frame.
 352  *
 353  * This function is called when a frame is ready, so as to prepare the next frame.
 354  */
 355 int microdia_next_frame(struct usb_microdia *dev)
 356 {
 357         int ret = 0;
 358         unsigned long flags;
 359
 360         UDIA_STREAM("Select next frame\n");
 361
 362         spin_lock_irqsave(&dev->spinlock, flags);
 363
 364         if (dev->fill_frame != NULL) {
 365                 if (dev->full_frames == NULL) {
 366                         dev->full_frames = dev->fill_frame;
 367                         dev->full_frames_tail = dev->full_frames;
 368                 }
 369                 else {
 370                         dev->full_frames_tail->next = dev->fill_frame;
 371                         dev->full_frames_tail = dev->fill_frame;
 372                 }
 373         }
 374
 375         if (dev->empty_frames != NULL) {
 376                 dev->fill_frame = dev->empty_frames;
 377                 dev->empty_frames = dev->empty_frames->next;
 378         }
 379         else {
 380                 if (dev->full_frames == NULL) {
 381                         UDIA_ERROR("Neither empty or full frames available!\n");
 382                         spin_unlock_irqrestore(&dev->spinlock, flags);
 383                         return -EINVAL;
 384                 }
 385
 386                 dev->fill_frame = dev->full_frames;
 387                 dev->full_frames = dev->full_frames->next;
 388
 389                 ret = 1;
 390         }
 391
 392         dev->fill_frame->next = NULL;
 393
 394         spin_unlock_irqrestore(&dev->spinlock, flags);
 395
 396         return ret;
 397 }
 398
 399
 400 /**
 401  * @param dev Device structure
 402  *
 403  * @returns 0 if all is OK
 404  *
 405  * @brief Handler frame
 406  *
 407  * This function gets called for the isochronous pipe. This function is only called
 408  * when a frame is ready. So we have to be fast to decompress the data.
 409  */
 410 int microdia_handle_frame(struct usb_microdia *dev)
 411 {
 412         int ret = 0;
 413         unsigned long flags;
 414
 415         UDIA_STREAM("Sync Handle Frame\n");
 416
 417         spin_lock_irqsave(&dev->spinlock, flags);
 418
 419         if (dev->read_frame != NULL) {
 420                 spin_unlock_irqrestore(&dev->spinlock, flags);
 421                 return ret;
 422         }
 423
 424         if (dev->full_frames == NULL) {
 425         }
 426         else {
 427                 dev->read_frame = dev->full_frames;
 428                 dev->full_frames = dev->full_frames->next;
 429                 dev->read_frame->next = NULL;
 430         }
 431
 432         if (dev->read_frame != NULL) {
 433                 spin_unlock_irqrestore(&dev->spinlock, flags);
 434                 ret = microdia_decompress(dev);
 435                 spin_lock_irqsave(&dev->spinlock, flags);
 436
 437                 if (dev->empty_frames == NULL) {
 438                         dev->empty_frames = dev->read_frame;
 439                         dev->empty_frames_tail = dev->empty_frames;
 440                 }
 441                 else {
 442                         dev->empty_frames_tail->next = dev->read_frame;
 443                         dev->empty_frames_tail = dev->read_frame;
 444                 }
 445
 446                 dev->read_frame = NULL;
 447         }
 448
 449         spin_unlock_irqrestore(&dev->spinlock, flags);
 450
 451         return ret;
 452 }
 453