src/am7xxx.c

   1 /* am7xxx - communication with AM7xxx based USB Pico Projectors and DPFs
   2  *
   3  * Copyright (C) 2012  Antonio Ospite <ospite@studenti.unina.it>
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <stdarg.h>
  23 #include <errno.h>
  24 #include <libusb.h>
  25 #include <math.h>
  26
  27 #include "am7xxx.h"
  28 #include "serialize.h"
  29
  30 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  31
  32 /* If we're not using GNU C, elide __attribute__
  33  * taken from: http://unixwiz.net/techtips/gnu-c-attributes.html)
  34  */
  35 #ifndef __GNUC__
  36 #  define  __attribute__(x)  /*NOTHING*/
  37 #endif
  38
  39 static void log_message(am7xxx_context *ctx,
  40                         int level,
  41                         const char *function,
  42                         int line,
  43                         const char *fmt,
  44                         ...) __attribute__ ((format (printf, 5, 6)));
  45
  46 #define fatal(...)        log_message(NULL, AM7XXX_LOG_FATAL,   __func__, __LINE__, __VA_ARGS__)
  47 #define error(ctx, ...)   log_message(ctx,  AM7XXX_LOG_ERROR,   __func__, __LINE__, __VA_ARGS__)
  48 #define warning(ctx, ...) log_message(ctx,  AM7XXX_LOG_WARNING, __func__, 0,        __VA_ARGS__)
  49 #define info(ctx, ...)    log_message(ctx,  AM7XXX_LOG_INFO,    __func__, 0,        __VA_ARGS__)
  50 #define debug(ctx, ...)   log_message(ctx,  AM7XXX_LOG_DEBUG,   __func__, 0,        __VA_ARGS__)
  51 #define trace(ctx, ...)   log_message(ctx,  AM7XXX_LOG_TRACE,   NULL,     0,        __VA_ARGS__)
  52
  53 struct am7xxx_usb_device_descriptor {
  54         const char *name;
  55         uint16_t vendor_id;
  56         uint16_t product_id;
  57 };
  58
  59 static struct am7xxx_usb_device_descriptor supported_devices[] = {
  60         {
  61                 .name       = "Acer C110",
  62                 .vendor_id  = 0x1de1,
  63                 .product_id = 0xc101,
  64         },
  65         {
  66                 .name       = "Philips/Sagemcom PicoPix 1020",
  67                 .vendor_id  = 0x21e7,
  68                 .product_id = 0x000e,
  69         },
  70 };
  71
  72 /* The header size on the wire is known to be always 24 bytes, regardless of
  73  * the memory configuration enforced by different architectures or compilers
  74  * for struct am7xxx_header
  75  */
  76 #define AM7XXX_HEADER_WIRE_SIZE 24
  77
  78 struct _am7xxx_device {
  79         libusb_device_handle *usb_device;
  80         uint8_t buffer[AM7XXX_HEADER_WIRE_SIZE];
  81         am7xxx_context *ctx;
  82         am7xxx_device *next;
  83 };
  84
  85 struct _am7xxx_context {
  86         libusb_context *usb_context;
  87         int log_level;
  88         am7xxx_device *devices_list;
  89 };
  90
  91 typedef enum {
  92         AM7XXX_PACKET_TYPE_DEVINFO = 0x01,
  93         AM7XXX_PACKET_TYPE_IMAGE   = 0x02,
  94         AM7XXX_PACKET_TYPE_POWER   = 0x04,
  95         AM7XXX_PACKET_TYPE_UNKNOWN = 0x05,
  96 } am7xxx_packet_type;
  97
  98 struct am7xxx_generic_header {
  99         uint32_t field0;
 100         uint32_t field1;
 101         uint32_t field2;
 102         uint32_t field3;
 103 };
 104
 105 struct am7xxx_devinfo_header {
 106         uint32_t native_width;
 107         uint32_t native_height;
 108         uint32_t unknown0;
 109         uint32_t unknown1;
 110 };
 111
 112 struct am7xxx_image_header {
 113         uint32_t format;
 114         uint32_t width;
 115         uint32_t height;
 116         uint32_t image_size;
 117 };
 118
 119 struct am7xxx_power_header {
 120         uint32_t bit2;
 121         uint32_t bit1;
 122         uint32_t bit0;
 123 };
 124
 125 /*
 126  * Examples of packet headers:
 127  *
 128  * Image header:
 129  * 02 00 00 00 00 10 3e 10 01 00 00 00 20 03 00 00 e0 01 00 00 53 E8 00 00
 130  *
 131  * Power header:
 132  * 04 00 00 00 00 0c ff ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 133  */
 134
 135 struct am7xxx_header {
 136         uint32_t packet_type;
 137         uint8_t unknown0;
 138         uint8_t header_data_len;
 139         uint8_t unknown2;
 140         uint8_t unknown3;
 141         union {
 142                 struct am7xxx_generic_header data;
 143                 struct am7xxx_devinfo_header devinfo;
 144                 struct am7xxx_image_header image;
 145                 struct am7xxx_power_header power;
 146         } header_data;
 147 };
 148
 149
 150 #ifdef DEBUG
 151 static void debug_dump_devinfo_header(am7xxx_context *ctx, struct am7xxx_devinfo_header *d)
 152 {
 153         if (ctx == NULL || d == NULL)
 154                 return;
 155
 156         debug(ctx, "Info header:\n");
 157         debug(ctx, "\tnative_width:  0x%08x (%u)\n", d->native_width, d->native_width);
 158         debug(ctx, "\tnative_height: 0x%08x (%u)\n", d->native_height, d->native_height);
 159         debug(ctx, "\tunknown0:      0x%08x (%u)\n", d->unknown0, d->unknown0);
 160         debug(ctx, "\tunknown1:      0x%08x (%u)\n", d->unknown1, d->unknown1);
 161 }
 162
 163 static void debug_dump_image_header(am7xxx_context *ctx, struct am7xxx_image_header *i)
 164 {
 165         if (ctx == NULL || i == NULL)
 166                 return;
 167
 168         debug(ctx, "Image header:\n");
 169         debug(ctx, "\tformat:     0x%08x (%u)\n", i->format, i->format);
 170         debug(ctx, "\twidth:      0x%08x (%u)\n", i->width, i->width);
 171         debug(ctx, "\theight:     0x%08x (%u)\n", i->height, i->height);
 172         debug(ctx, "\timage size: 0x%08x (%u)\n", i->image_size, i->image_size);
 173 }
 174
 175 static void debug_dump_power_header(am7xxx_context *ctx, struct am7xxx_power_header *p)
 176 {
 177         if (ctx == NULL || p == NULL)
 178                 return;
 179
 180         debug(ctx, "Power header:\n");
 181         debug(ctx, "\tbit2: 0x%08x (%u)\n", p->bit2, p->bit2);
 182         debug(ctx, "\tbit1: 0x%08x (%u)\n", p->bit1, p->bit1);
 183         debug(ctx, "\tbit0: 0x%08x (%u)\n", p->bit0, p->bit0);
 184 }
 185
 186 static void debug_dump_header(am7xxx_context *ctx, struct am7xxx_header *h)
 187 {
 188         if (ctx == NULL || h == NULL)
 189                 return;
 190
 191         debug(ctx, "BEGIN\n");
 192         debug(ctx, "packet_type:     0x%08x (%u)\n", h->packet_type, h->packet_type);
 193         debug(ctx, "unknown0:        0x%02hhx (%hhu)\n", h->unknown0, h->unknown0);
 194         debug(ctx, "header_data_len: 0x%02hhx (%hhu)\n", h->header_data_len, h->header_data_len);
 195         debug(ctx, "unknown2:        0x%02hhx (%hhu)\n", h->unknown2, h->unknown2);
 196         debug(ctx, "unknown3:        0x%02hhx (%hhu)\n", h->unknown3, h->unknown3);
 197
 198         switch(h->packet_type) {
 199         case AM7XXX_PACKET_TYPE_DEVINFO:
 200                 debug_dump_devinfo_header(ctx, &(h->header_data.devinfo));
 201                 break;
 202
 203         case AM7XXX_PACKET_TYPE_IMAGE:
 204                 debug_dump_image_header(ctx, &(h->header_data.image));
 205                 break;
 206
 207         case AM7XXX_PACKET_TYPE_POWER:
 208                 debug_dump_power_header(ctx, &(h->header_data.power));
 209                 break;
 210
 211         default:
 212                 debug(ctx, "Packet type not supported!\n");
 213                 break;
 214         }
 215         debug(ctx, "END\n\n");
 216 }
 217
 218 static inline unsigned int in_80chars(unsigned int i)
 219 {
 220         /* The 3 below is the length of "xx " where xx is the hex string
 221          * representation of a byte */
 222         return ((i+1) % (80/3));
 223 }
 224
 225 static void trace_dump_buffer(am7xxx_context *ctx, const char *message,
 226                               uint8_t *buffer, unsigned int len)
 227 {
 228         unsigned int i;
 229
 230         if (ctx == NULL || buffer == NULL || len == 0)
 231                 return;
 232
 233         trace(ctx, "\n");
 234         if (message)
 235                 trace(ctx, "%s\n", message);
 236
 237         for (i = 0; i < len; i++) {
 238                 trace(ctx, "%02hhX%c", buffer[i], (in_80chars(i) && (i < len - 1)) ? ' ' : '\n');
 239         }
 240         trace(ctx, "\n");
 241 }
 242 #else
 243 static void debug_dump_header(am7xxx_context *ctx, struct am7xxx_header *h)
 244 {
 245         (void)ctx;
 246         (void)h;
 247 }
 248
 249 static void trace_dump_buffer(am7xxx_context *ctx, const char *message,
 250                               uint8_t *buffer, unsigned int len)
 251 {
 252         (void)ctx;
 253         (void)message;
 254         (void)buffer;
 255         (void)len;
 256 }
 257 #endif /* DEBUG */
 258
 259 static int read_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 260 {
 261         int ret;
 262         int transferred = 0;
 263
 264         ret = libusb_bulk_transfer(dev->usb_device, 0x81, buffer, len, &transferred, 0);
 265         if (ret != 0 || (unsigned int)transferred != len) {
 266                 error(dev->ctx, "ret: %d\ttransferred: %d (expected %u)\n",
 267                       ret, transferred, len);
 268                 return ret;
 269         }
 270
 271         trace_dump_buffer(dev->ctx, "<-- received", buffer, len);
 272
 273         return 0;
 274 }
 275
 276 static int send_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 277 {
 278         int ret;
 279         int transferred = 0;
 280
 281         trace_dump_buffer(dev->ctx, "sending -->", buffer, len);
 282
 283         ret = libusb_bulk_transfer(dev->usb_device, 1, buffer, len, &transferred, 0);
 284         if (ret != 0 || (unsigned int)transferred != len) {
 285                 error(dev->ctx, "ret: %d\ttransferred: %d (expected %u)\n",
 286                       ret, transferred, len);
 287                 return ret;
 288         }
 289
 290         return 0;
 291 }
 292
 293 static void serialize_header(struct am7xxx_header *h, uint8_t *buffer)
 294 {
 295         uint8_t **buffer_iterator = &buffer;
 296
 297         put_le32(h->packet_type, buffer_iterator);
 298         put_8(h->unknown0, buffer_iterator);
 299         put_8(h->header_data_len, buffer_iterator);
 300         put_8(h->unknown2, buffer_iterator);
 301         put_8(h->unknown3, buffer_iterator);
 302         put_le32(h->header_data.data.field0, buffer_iterator);
 303         put_le32(h->header_data.data.field1, buffer_iterator);
 304         put_le32(h->header_data.data.field2, buffer_iterator);
 305         put_le32(h->header_data.data.field3, buffer_iterator);
 306 }
 307
 308 static void unserialize_header(uint8_t *buffer, struct am7xxx_header *h)
 309 {
 310         uint8_t **buffer_iterator = &buffer;
 311
 312         h->packet_type = get_le32(buffer_iterator);
 313         h->unknown0 = get_8(buffer_iterator);
 314         h->header_data_len = get_8(buffer_iterator);
 315         h->unknown2 = get_8(buffer_iterator);
 316         h->unknown3 = get_8(buffer_iterator);
 317         h->header_data.data.field0 = get_le32(buffer_iterator);
 318         h->header_data.data.field1 = get_le32(buffer_iterator);
 319         h->header_data.data.field2 = get_le32(buffer_iterator);
 320         h->header_data.data.field3 = get_le32(buffer_iterator);
 321 }
 322
 323 static int read_header(am7xxx_device *dev, struct am7xxx_header *h)
 324 {
 325         int ret;
 326
 327         ret = read_data(dev, dev->buffer, AM7XXX_HEADER_WIRE_SIZE);
 328         if (ret < 0)
 329                 goto out;
 330
 331         unserialize_header(dev->buffer, h);
 332
 333         debug_dump_header(dev->ctx, h);
 334
 335         ret = 0;
 336
 337 out:
 338         return ret;
 339 }
 340
 341 static int send_header(am7xxx_device *dev, struct am7xxx_header *h)
 342 {
 343         int ret;
 344
 345         debug_dump_header(dev->ctx, h);
 346
 347         serialize_header(h, dev->buffer);
 348         ret = send_data(dev, dev->buffer, AM7XXX_HEADER_WIRE_SIZE);
 349         if (ret < 0)
 350                 error(dev->ctx, "failed to send data\n");
 351
 352         return ret;
 353 }
 354
 355 /* When level == AM7XXX_LOG_FATAL do not check the log_level from the context
 356  * and print the message unconditionally, this makes it possible to print
 357  * fatal messages even early on initialization, before the context has been
 358  * set up */
 359 static void log_message(am7xxx_context *ctx,
 360                         int level,
 361                         const char *function,
 362                         int line,
 363                         const char *fmt,
 364                         ...)
 365 {
 366         va_list ap;
 367
 368         if (level == AM7XXX_LOG_FATAL || (ctx && level <= ctx->log_level)) {
 369                 if (function) {
 370                         fprintf(stderr, "%s", function);
 371                         if (line)
 372                                 fprintf(stderr, "[%d]", line);
 373                         fprintf(stderr, ": ");
 374                 }
 375
 376                 va_start(ap, fmt);
 377                 vfprintf(stderr, fmt, ap);
 378                 va_end(ap);
 379         }
 380
 381         return;
 382 }
 383
 384 static am7xxx_device *add_new_device(am7xxx_context *ctx)
 385 {
 386         am7xxx_device **devices_list;
 387         am7xxx_device *new_device;
 388
 389         if (ctx == NULL) {
 390                 fatal("context must not be NULL!\n");
 391                 return NULL;
 392         }
 393
 394         devices_list = &(ctx->devices_list);
 395
 396         new_device = malloc(sizeof(*new_device));
 397         if (new_device == NULL) {
 398                 fatal("cannot allocate a new device (%s)\n", strerror(errno));
 399                 return NULL;
 400         }
 401         memset(new_device, 0, sizeof(*new_device));
 402
 403         new_device->ctx = ctx;
 404
 405         if (*devices_list == NULL) {
 406                 *devices_list = new_device;
 407         } else {
 408                 am7xxx_device *prev = *devices_list;
 409                 while (prev->next)
 410                         prev = prev->next;
 411                 prev->next = new_device;
 412         }
 413         return new_device;
 414 }
 415
 416 static am7xxx_device *find_device(am7xxx_context *ctx,
 417                                   unsigned int device_index)
 418 {
 419         unsigned int i = 0;
 420         am7xxx_device *current;
 421
 422         if (ctx == NULL) {
 423                 fatal("context must not be NULL!\n");
 424                 return NULL;
 425         }
 426
 427         current = ctx->devices_list;
 428         while (current && i++ < device_index)
 429                 current = current->next;
 430
 431         return current;
 432 }
 433
 434 typedef enum {
 435         SCAN_OP_BUILD_DEVLIST,
 436         SCAN_OP_OPEN_DEVICE,
 437 } scan_op;
 438
 439 /**
 440  * This is where the central logic of multi-device support is.
 441  *
 442  * When 'op' == SCAN_OP_BUILD_DEVLIST the parameters 'open_device_index' and
 443  * 'dev' are ignored; the function returns 0 on success and a negative value
 444  * on error.
 445  *
 446  * When 'op' == SCAN_OP_OPEN_DEVICE the function opens the supported USB
 447  * device with index 'open_device_index' and returns the correspondent
 448  * am7xxx_device in the 'dev' parameter; the function returns 0 on success,
 449  * 1 if the device was already open and a negative value on error.
 450  *
 451  * NOTES:
 452  * if scan_devices() fails when called with 'op' == SCAN_OP_BUILD_DEVLIST,
 453  * the caller might want to call am7xxx_shutdown() in order to remove
 454  * devices possibly added before the failure.
 455  */
 456 static int scan_devices(am7xxx_context *ctx, scan_op op,
 457                         unsigned int open_device_index, am7xxx_device **dev)
 458 {
 459         int num_devices;
 460         libusb_device** list;
 461         unsigned int current_index;
 462         int i;
 463         int ret;
 464
 465         if (ctx == NULL) {
 466                 fatal("context must not be NULL!\n");
 467                 return -EINVAL;
 468         }
 469         if (op == SCAN_OP_BUILD_DEVLIST && ctx->devices_list != NULL) {
 470                 error(ctx, "device scan done already? Abort!\n");
 471                 return -EINVAL;
 472         }
 473
 474         num_devices = libusb_get_device_list(ctx->usb_context, &list);
 475         if (num_devices < 0) {
 476                 ret = -ENODEV;
 477                 goto out;
 478         }
 479
 480         current_index = 0;
 481         for (i = 0; i < num_devices; i++) {
 482                 struct libusb_device_descriptor desc;
 483                 unsigned int j;
 484
 485                 ret = libusb_get_device_descriptor(list[i], &desc);
 486                 if (ret < 0)
 487                         continue;
 488
 489                 for (j = 0; j < ARRAY_SIZE(supported_devices); j++) {
 490                         if (desc.idVendor == supported_devices[j].vendor_id
 491                             && desc.idProduct == supported_devices[j].product_id) {
 492
 493                                 if (op == SCAN_OP_BUILD_DEVLIST) {
 494                                         am7xxx_device *new_device;
 495                                         info(ctx, "am7xxx device found, index: %d, name: %s\n",
 496                                              current_index,
 497                                              supported_devices[j].name);
 498                                         new_device = add_new_device(ctx);
 499                                         if (new_device == NULL) {
 500                                                 /* XXX, the caller may want
 501                                                  * to call am7xxx_shutdown() if
 502                                                  * we fail here, as we may have
 503                                                  * added some devices already
 504                                                  */
 505                                                 debug(ctx, "Cannot create a new device\n");
 506                                                 ret = -ENODEV;
 507                                                 goto out;
 508                                         }
 509                                 } else if (op == SCAN_OP_OPEN_DEVICE &&
 510                                            current_index == open_device_index) {
 511
 512                                         *dev = find_device(ctx, open_device_index);
 513                                         if (*dev == NULL) {
 514                                                 ret = -ENODEV;
 515                                                 goto out;
 516                                         }
 517
 518                                         /* the usb device has already been opened */
 519                                         if ((*dev)->usb_device) {
 520                                                 debug(ctx, "(*dev)->usb_device already set\n");
 521                                                 ret = 1;
 522                                                 goto out;
 523                                         }
 524
 525                                         ret = libusb_open(list[i], &((*dev)->usb_device));
 526                                         if (ret < 0) {
 527                                                 debug(ctx, "libusb_open failed\n");
 528                                                 goto out;
 529                                         }
 530
 531                                         libusb_set_configuration((*dev)->usb_device, 1);
 532                                         libusb_claim_interface((*dev)->usb_device, 0);
 533                                         goto out;
 534                                 }
 535                                 current_index++;
 536                         }
 537                 }
 538         }
 539
 540         /* if we made it up to here we didn't find any device to open */
 541         if (op == SCAN_OP_OPEN_DEVICE) {
 542                 error(ctx, "Cannot find any device to open\n");
 543                 ret = -ENODEV;
 544                 goto out;
 545         }
 546
 547         /* everything went fine when building the device list */
 548         ret = 0;
 549 out:
 550         libusb_free_device_list(list, 1);
 551         return ret;
 552 }
 553
 554 int am7xxx_init(am7xxx_context **ctx)
 555 {
 556         int ret = 0;
 557
 558         *ctx = malloc(sizeof(**ctx));
 559         if (*ctx == NULL) {
 560                 fatal("cannot allocate the context (%s)\n", strerror(errno));
 561                 ret = -ENOMEM;
 562                 goto out;
 563         }
 564         memset(*ctx, 0, sizeof(**ctx));
 565
 566         /* Set the highest log level during initialization */
 567         (*ctx)->log_level = AM7XXX_LOG_TRACE;
 568
 569         ret = libusb_init(&((*ctx)->usb_context));
 570         if (ret < 0)
 571                 goto out_free_context;
 572
 573         libusb_set_debug((*ctx)->usb_context, 3);
 574
 575         ret = scan_devices(*ctx, SCAN_OP_BUILD_DEVLIST , 0, NULL);
 576         if (ret < 0) {
 577                 error(*ctx, "scan_devices() failed\n");
 578                 am7xxx_shutdown(*ctx);
 579                 goto out;
 580         }
 581
 582         /* Set a quieter log level as default for normal operation */
 583         (*ctx)->log_level = AM7XXX_LOG_ERROR;
 584         return 0;
 585
 586 out_free_context:
 587         free(*ctx);
 588         *ctx = NULL;
 589 out:
 590         return ret;
 591 }
 592
 593 void am7xxx_shutdown(am7xxx_context *ctx)
 594 {
 595         am7xxx_device *current;
 596
 597         if (ctx == NULL) {
 598                 fatal("context must not be NULL!\n");
 599                 return;
 600         }
 601
 602         current = ctx->devices_list;
 603         while (current) {
 604                 am7xxx_device *next = current->next;
 605                 am7xxx_close_device(current);
 606                 free(current);
 607                 current = next;
 608         }
 609
 610         libusb_exit(ctx->usb_context);
 611         free(ctx);
 612         ctx = NULL;
 613 }
 614
 615 void am7xxx_set_log_level(am7xxx_context *ctx, am7xxx_log_level log_level)
 616 {
 617         ctx->log_level = log_level;
 618 }
 619
 620 int am7xxx_open_device(am7xxx_context *ctx, am7xxx_device **dev,
 621                        unsigned int device_index)
 622 {
 623         int ret;
 624
 625         if (ctx == NULL) {
 626                 fatal("context must not be NULL!\n");
 627                 return -EINVAL;
 628         }
 629
 630         ret = scan_devices(ctx, SCAN_OP_OPEN_DEVICE, device_index, dev);
 631         if (ret < 0) {
 632                 errno = ENODEV;
 633         } else if (ret > 0) {
 634                 warning(ctx, "device %d already open\n", device_index);
 635                 errno = EBUSY;
 636                 ret = -EBUSY;
 637         }
 638
 639         return ret;
 640 }
 641
 642 int am7xxx_close_device(am7xxx_device *dev)
 643 {
 644         if (dev == NULL) {
 645                 fatal("dev must not be NULL!\n");
 646                 return -EINVAL;
 647         }
 648         if (dev->usb_device) {
 649                 libusb_release_interface(dev->usb_device, 0);
 650                 libusb_close(dev->usb_device);
 651                 dev->usb_device = NULL;
 652         }
 653         return 0;
 654 }
 655
 656 int am7xxx_get_device_info(am7xxx_device *dev,
 657                            am7xxx_device_info *device_info)
 658 {
 659         int ret;
 660         struct am7xxx_header h = {
 661                 .packet_type     = AM7XXX_PACKET_TYPE_DEVINFO,
 662                 .unknown0        = 0x00,
 663                 .header_data_len = 0x00,
 664                 .unknown2        = 0x3e,
 665                 .unknown3        = 0x10,
 666                 .header_data = {
 667                         .devinfo = {
 668                                 .native_width  = 0,
 669                                 .native_height = 0,
 670                                 .unknown0      = 0,
 671                                 .unknown1      = 0,
 672                         },
 673                 },
 674         };
 675
 676         ret = send_header(dev, &h);
 677         if (ret < 0)
 678                 return ret;
 679
 680         ret = read_header(dev, &h);
 681         if (ret < 0)
 682                 return ret;
 683
 684         device_info->native_width = h.header_data.devinfo.native_width;
 685         device_info->native_height = h.header_data.devinfo.native_height;
 686 #if 0
 687         /* No reason to expose these in the public API until we know what they mean */
 688         device_info->unknown0 = h.header_data.devinfo.unknown0;
 689         device_info->unknown1 = h.header_data.devinfo.unknown1;
 690 #endif
 691
 692         return 0;
 693 }
 694
 695 int am7xxx_calc_scaled_image_dimensions(am7xxx_device *dev,
 696                                         unsigned int upscale,
 697                                         unsigned int original_width,
 698                                         unsigned int original_height,
 699                                         unsigned int *scaled_width,
 700                                         unsigned int *scaled_height)
 701 {
 702
 703         am7xxx_device_info device_info;
 704         float width_ratio;
 705         float height_ratio;
 706         int ret;
 707
 708         ret = am7xxx_get_device_info(dev, &device_info);
 709         if (ret < 0) {
 710                 error(dev->ctx, "cannot get device info\n");
 711                 return ret;
 712         }
 713
 714         /*
 715          * Check if we need to rescale; if the input image fits the native
 716          * dimensions there is no need to, unless we want to upscale.
 717          */
 718         if (!upscale &&
 719             original_width <= device_info.native_width &&
 720             original_height <= device_info.native_height ) {
 721                 debug(dev->ctx, "CASE 0, no rescaling, the original image fits already\n");
 722                 *scaled_width = original_width;
 723                 *scaled_height = original_height;
 724                 return 0;
 725         }
 726
 727         /* Input dimensions relative to the device native dimensions */
 728         width_ratio =  (float)original_width / device_info.native_width;
 729         height_ratio = (float)original_height / device_info.native_height;
 730
 731         if (width_ratio > height_ratio) {
 732                 /*
 733                  * The input is proportionally "wider" than the device viewport
 734                  * so its height needs to be adjusted
 735                  */
 736                 debug(dev->ctx, "CASE 1, original image wider, adjust the scaled height\n");
 737                 *scaled_width = device_info.native_width;
 738                 *scaled_height = (unsigned int)lroundf(original_height / width_ratio);
 739         } else if (width_ratio < height_ratio) {
 740                 /*
 741                  * The input is proportionally "taller" than the device viewport
 742                  * so its width needs to be adjusted
 743                  */
 744                 debug(dev->ctx, "CASE 2 original image taller, adjust the scaled width\n");
 745                 *scaled_width = (unsigned int)lroundf(original_width / height_ratio);
 746                 *scaled_height = device_info.native_height;
 747         } else {
 748                 debug(dev->ctx, "CASE 3, just rescale, same aspect ratio already\n");
 749                 *scaled_width = device_info.native_width;
 750                 *scaled_height = device_info.native_height;
 751         }
 752         debug(dev->ctx, "scaled dimensions: %dx%d\n", *scaled_width, *scaled_height);
 753
 754         return 0;
 755 }
 756
 757 int am7xxx_send_image(am7xxx_device *dev,
 758                       am7xxx_image_format format,
 759                       unsigned int width,
 760                       unsigned int height,
 761                       uint8_t *image,
 762                       unsigned int image_size)
 763 {
 764         int ret;
 765         struct am7xxx_header h = {
 766                 .packet_type     = AM7XXX_PACKET_TYPE_IMAGE,
 767                 .unknown0        = 0x00,
 768                 .header_data_len = sizeof(struct am7xxx_image_header),
 769                 .unknown2        = 0x3e,
 770                 .unknown3        = 0x10,
 771                 .header_data = {
 772                         .image = {
 773                                 .format     = format,
 774                                 .width      = width,
 775                                 .height     = height,
 776                                 .image_size = image_size,
 777                         },
 778                 },
 779         };
 780
 781         ret = send_header(dev, &h);
 782         if (ret < 0)
 783                 return ret;
 784
 785         if (image == NULL || image_size == 0) {
 786                 warning(dev->ctx, "Not sending any data, check the 'image' or 'image_size' parameters\n");
 787                 return 0;
 788         }
 789
 790         return send_data(dev, image, image_size);
 791 }
 792
 793 int am7xxx_set_power_mode(am7xxx_device *dev, am7xxx_power_mode mode)
 794 {
 795         int ret;
 796         struct am7xxx_header h = {
 797                 .packet_type     = AM7XXX_PACKET_TYPE_POWER,
 798                 .unknown0        = 0x00,
 799                 .header_data_len = sizeof(struct am7xxx_power_header),
 800                 .unknown2        = 0x3e,
 801                 .unknown3        = 0x10,
 802         };
 803
 804         switch(mode) {
 805         case AM7XXX_POWER_OFF:
 806                 h.header_data.power.bit2 = 0;
 807                 h.header_data.power.bit1 = 0;
 808                 h.header_data.power.bit0 = 0;
 809                 break;
 810
 811         case AM7XXX_POWER_LOW:
 812                 h.header_data.power.bit2 = 0;
 813                 h.header_data.power.bit1 = 0;
 814                 h.header_data.power.bit0 = 1;
 815
 816         case AM7XXX_POWER_MIDDLE:
 817                 h.header_data.power.bit2 = 0;
 818                 h.header_data.power.bit1 = 1;
 819                 h.header_data.power.bit0 = 0;
 820                 break;
 821
 822         case AM7XXX_POWER_HIGH:
 823                 h.header_data.power.bit2 = 0;
 824                 h.header_data.power.bit1 = 1;
 825                 h.header_data.power.bit0 = 1;
 826                 break;
 827
 828         case AM7XXX_POWER_TURBO:
 829                 h.header_data.power.bit2 = 1;
 830                 h.header_data.power.bit1 = 0;
 831                 h.header_data.power.bit0 = 0;
 832                 break;
 833
 834         default:
 835                 error(dev->ctx, "Power mode not supported!\n");
 836                 return -EINVAL;
 837         };
 838
 839         ret = send_header(dev, &h);
 840         if (ret < 0)
 841                 return ret;
 842
 843         return 0;
 844 }