src/am7xxx.c

   1 /* am7xxx - communication with AM7xxx based USB Pico Projectors and DPFs
   2  *
   3  * Copyright (C) 2012-2014  Antonio Ospite <ao2@ao2.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 #include "tools.h"
  30
  31 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  32
  33 /*
  34  * If we're not using GNU C, elide __attribute__
  35  * taken from: http://unixwiz.net/techtips/gnu-c-attributes.html)
  36  */
  37 #ifndef __GNUC__
  38         #define  __attribute__(x)  /* NOTHING */
  39 #endif
  40
  41 /* Control shared library symbols visibility */
  42 #if defined _WIN32 || defined __CYGWIN__
  43         #define AM7XXX_PUBLIC __declspec(dllexport)
  44         #define AM7XXX_LOCAL
  45 #else
  46         #if __GNUC__ >= 4
  47                 #define AM7XXX_PUBLIC __attribute__ ((visibility ("default")))
  48                 #define AM7XXX_LOCAL  __attribute__ ((visibility ("hidden")))
  49         #else
  50                 #define AM7XXX_PUBLIC
  51                 #define AM7XXX_LOCAL
  52         #endif
  53 #endif
  54
  55 static void log_message(am7xxx_context *ctx,
  56                         int level,
  57                         const char *function_name,
  58                         int line,
  59                         const char *fmt,
  60                         ...) __attribute__ ((format (printf, 5, 6)));
  61
  62 #define fatal(...)        log_message(NULL, AM7XXX_LOG_FATAL,   __func__, __LINE__, __VA_ARGS__)
  63 #define error(ctx, ...)   log_message(ctx,  AM7XXX_LOG_ERROR,   __func__, __LINE__, __VA_ARGS__)
  64 #define warning(ctx, ...) log_message(ctx,  AM7XXX_LOG_WARNING, __func__, 0,        __VA_ARGS__)
  65 #define info(ctx, ...)    log_message(ctx,  AM7XXX_LOG_INFO,    __func__, 0,        __VA_ARGS__)
  66 #define debug(ctx, ...)   log_message(ctx,  AM7XXX_LOG_DEBUG,   __func__, 0,        __VA_ARGS__)
  67 #define trace(ctx, ...)   log_message(ctx,  AM7XXX_LOG_TRACE,   NULL,     0,        __VA_ARGS__)
  68
  69 struct am7xxx_ops {
  70         int (*set_power_mode)(am7xxx_device *dev, am7xxx_power_mode power);
  71         int (*set_zoom_mode)(am7xxx_device *dev, am7xxx_zoom_mode zoom);
  72 };
  73
  74 struct am7xxx_usb_device_descriptor {
  75         const char *name;
  76         uint16_t vendor_id;
  77         uint16_t product_id;
  78         uint8_t configuration;    /* The bConfigurationValue of the device */
  79         uint8_t interface_number; /* The bInterfaceNumber of the device */
  80         struct am7xxx_ops ops;
  81 };
  82
  83 static int default_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power);
  84 static int picopix_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power);
  85 static int default_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom);
  86 static int picopix_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom);
  87
  88 #define DEFAULT_OPS { \
  89         .set_power_mode = default_set_power_mode, \
  90         .set_zoom_mode = default_set_zoom_mode, \
  91 }
  92
  93 static const struct am7xxx_usb_device_descriptor supported_devices[] = {
  94         {
  95                 .name       = "Acer C110",
  96                 .vendor_id  = 0x1de1,
  97                 .product_id = 0xc101,
  98                 .configuration    = 2,
  99                 .interface_number = 0,
 100                 .ops = DEFAULT_OPS,
 101         },
 102         {
 103                 .name       = "Acer C112",
 104                 .vendor_id  = 0x1de1,
 105                 .product_id = 0x5501,
 106                 .configuration    = 2,
 107                 .interface_number = 0,
 108                 .ops = DEFAULT_OPS,
 109         },
 110         {
 111                 .name       ="Aiptek PocketCinema T25",
 112                 .vendor_id  = 0x08ca,
 113                 .product_id = 0x2144,
 114                 .configuration    = 2,
 115                 .interface_number = 0,
 116                 .ops = DEFAULT_OPS,
 117         },
 118         {
 119                 .name       = "Philips/Sagemcom PicoPix 1020",
 120                 .vendor_id  = 0x21e7,
 121                 .product_id = 0x000e,
 122                 .configuration    = 2,
 123                 .interface_number = 0,
 124                 .ops = DEFAULT_OPS,
 125         },
 126         {
 127                 .name       = "Philips/Sagemcom PicoPix 2055",
 128                 .vendor_id  = 0x21e7,
 129                 .product_id = 0x0016,
 130                 .configuration    = 2,
 131                 .interface_number = 0,
 132                 .ops = {
 133                         .set_power_mode = picopix_set_power_mode,
 134                         .set_zoom_mode = picopix_set_zoom_mode,
 135                 },
 136         },
 137         {
 138                 .name       = "Philips/Sagemcom PicoPix 2330",
 139                 .vendor_id  = 0x21e7,
 140                 .product_id = 0x0019,
 141                 .configuration    = 1,
 142                 .interface_number = 0,
 143         },
 144 };
 145
 146 /* The header size on the wire is known to be always 24 bytes, regardless of
 147  * the memory configuration enforced by different architectures or compilers
 148  * for struct am7xxx_header
 149  */
 150 #define AM7XXX_HEADER_WIRE_SIZE 24
 151
 152 struct _am7xxx_device {
 153         libusb_device_handle *usb_device;
 154         struct libusb_transfer *transfer;
 155         int transfer_completed;
 156         uint8_t buffer[AM7XXX_HEADER_WIRE_SIZE];
 157         am7xxx_device_info *device_info;
 158         am7xxx_context *ctx;
 159         const struct am7xxx_usb_device_descriptor *desc;
 160         am7xxx_device *next;
 161 };
 162
 163 struct _am7xxx_context {
 164         libusb_context *usb_context;
 165         int log_level;
 166         am7xxx_device *devices_list;
 167 };
 168
 169 typedef enum {
 170         AM7XXX_PACKET_TYPE_DEVINFO = 0x01,
 171         AM7XXX_PACKET_TYPE_IMAGE   = 0x02,
 172         AM7XXX_PACKET_TYPE_POWER   = 0x04,
 173         AM7XXX_PACKET_TYPE_ZOOM    = 0x05,
 174         AM7XXX_PACKET_TYPE_PICOPIX_POWER_LOW    = 0x15,
 175         AM7XXX_PACKET_TYPE_PICOPIX_POWER_MEDIUM = 0x16,
 176         AM7XXX_PACKET_TYPE_PICOPIX_POWER_HIGH   = 0x17,
 177         AM7XXX_PACKET_TYPE_PICOPIX_ENABLE_TI    = 0x18,
 178         AM7XXX_PACKET_TYPE_PICOPIX_DISABLE_TI   = 0x19,
 179 } am7xxx_packet_type;
 180
 181 struct am7xxx_generic_header {
 182         uint32_t field0;
 183         uint32_t field1;
 184         uint32_t field2;
 185         uint32_t field3;
 186 };
 187
 188 struct am7xxx_devinfo_header {
 189         uint32_t native_width;
 190         uint32_t native_height;
 191         uint32_t unknown0;
 192         uint32_t unknown1;
 193 };
 194
 195 struct am7xxx_image_header {
 196         uint32_t format;
 197         uint32_t width;
 198         uint32_t height;
 199         uint32_t image_size;
 200 };
 201
 202 struct am7xxx_power_header {
 203         uint32_t bit2;
 204         uint32_t bit1;
 205         uint32_t bit0;
 206 };
 207
 208 struct am7xxx_zoom_header {
 209         uint32_t bit1;
 210         uint32_t bit0;
 211 };
 212
 213 /*
 214  * Examples of packet headers:
 215  *
 216  * Image header:
 217  * 02 00 00 00 00 10 3e 10 01 00 00 00 20 03 00 00 e0 01 00 00 53 E8 00 00
 218  *
 219  * Power header:
 220  * 04 00 00 00 00 0c ff ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 221  */
 222
 223 /* Direction of the communication from the host point of view */
 224 #define AM7XXX_DIRECTION_OUT 0 /* host -> device */
 225 #define AM7XXX_DIRECTION_IN  1 /* host <- device */
 226
 227 struct am7xxx_header {
 228         uint32_t packet_type;
 229         uint8_t direction;
 230         uint8_t header_data_len;
 231         uint8_t unknown2;
 232         uint8_t unknown3;
 233         union {
 234                 struct am7xxx_generic_header data;
 235                 struct am7xxx_devinfo_header devinfo;
 236                 struct am7xxx_image_header image;
 237                 struct am7xxx_power_header power;
 238                 struct am7xxx_zoom_header zoom;
 239         } header_data;
 240 };
 241
 242
 243 #ifdef DEBUG
 244 static void debug_dump_generic_header(am7xxx_context *ctx, struct am7xxx_generic_header *g)
 245 {
 246         if (ctx == NULL || g == NULL)
 247                 return;
 248
 249         debug(ctx, "Generic header:\n");
 250         debug(ctx, "\tfield0:  0x%08x (%u)\n", g->field0, g->field0);
 251         debug(ctx, "\tfield1:  0x%08x (%u)\n", g->field1, g->field1);
 252         debug(ctx, "\tfield2:  0x%08x (%u)\n", g->field2, g->field2);
 253         debug(ctx, "\tfield3:  0x%08x (%u)\n", g->field3, g->field3);
 254 }
 255
 256 static void debug_dump_devinfo_header(am7xxx_context *ctx, struct am7xxx_devinfo_header *d)
 257 {
 258         if (ctx == NULL || d == NULL)
 259                 return;
 260
 261         debug(ctx, "Info header:\n");
 262         debug(ctx, "\tnative_width:  0x%08x (%u)\n", d->native_width, d->native_width);
 263         debug(ctx, "\tnative_height: 0x%08x (%u)\n", d->native_height, d->native_height);
 264         debug(ctx, "\tunknown0:      0x%08x (%u)\n", d->unknown0, d->unknown0);
 265         debug(ctx, "\tunknown1:      0x%08x (%u)\n", d->unknown1, d->unknown1);
 266 }
 267
 268 static void debug_dump_image_header(am7xxx_context *ctx, struct am7xxx_image_header *i)
 269 {
 270         if (ctx == NULL || i == NULL)
 271                 return;
 272
 273         debug(ctx, "Image header:\n");
 274         debug(ctx, "\tformat:     0x%08x (%u)\n", i->format, i->format);
 275         debug(ctx, "\twidth:      0x%08x (%u)\n", i->width, i->width);
 276         debug(ctx, "\theight:     0x%08x (%u)\n", i->height, i->height);
 277         debug(ctx, "\timage size: 0x%08x (%u)\n", i->image_size, i->image_size);
 278 }
 279
 280 static void debug_dump_power_header(am7xxx_context *ctx, struct am7xxx_power_header *p)
 281 {
 282         if (ctx == NULL || p == NULL)
 283                 return;
 284
 285         debug(ctx, "Power header:\n");
 286         debug(ctx, "\tbit2: 0x%08x (%u)\n", p->bit2, p->bit2);
 287         debug(ctx, "\tbit1: 0x%08x (%u)\n", p->bit1, p->bit1);
 288         debug(ctx, "\tbit0: 0x%08x (%u)\n", p->bit0, p->bit0);
 289 }
 290
 291 static void debug_dump_zoom_header(am7xxx_context *ctx, struct am7xxx_zoom_header *z)
 292 {
 293         if (ctx == NULL || z == NULL)
 294                 return;
 295
 296         debug(ctx, "Zoom header:\n");
 297         debug(ctx, "\tbit1: 0x%08x (%u)\n", z->bit1, z->bit1);
 298         debug(ctx, "\tbit0: 0x%08x (%u)\n", z->bit0, z->bit0);
 299 }
 300
 301 static void debug_dump_header(am7xxx_context *ctx, struct am7xxx_header *h)
 302 {
 303         if (ctx == NULL || h == NULL)
 304                 return;
 305
 306         debug(ctx, "BEGIN\n");
 307         debug(ctx, "packet_type:     0x%08x (%u)\n", h->packet_type, h->packet_type);
 308         debug(ctx, "direction:       0x%02hhx (%hhu) (%s)\n", h->direction, h->direction,
 309               h->direction == AM7XXX_DIRECTION_IN ? "IN" :
 310               h->direction == AM7XXX_DIRECTION_OUT ? "OUT" :
 311               "UNKNOWN");
 312         debug(ctx, "header_data_len: 0x%02hhx (%hhu)\n", h->header_data_len, h->header_data_len);
 313         debug(ctx, "unknown2:        0x%02hhx (%hhu)\n", h->unknown2, h->unknown2);
 314         debug(ctx, "unknown3:        0x%02hhx (%hhu)\n", h->unknown3, h->unknown3);
 315
 316         switch(h->packet_type) {
 317         case AM7XXX_PACKET_TYPE_DEVINFO:
 318                 debug_dump_devinfo_header(ctx, &(h->header_data.devinfo));
 319                 break;
 320
 321         case AM7XXX_PACKET_TYPE_IMAGE:
 322                 debug_dump_image_header(ctx, &(h->header_data.image));
 323                 break;
 324
 325         case AM7XXX_PACKET_TYPE_POWER:
 326                 debug_dump_power_header(ctx, &(h->header_data.power));
 327                 break;
 328
 329         case AM7XXX_PACKET_TYPE_ZOOM:
 330                 debug_dump_zoom_header(ctx, &(h->header_data.zoom));
 331                 break;
 332
 333         default:
 334                 debug(ctx, "Parsing data not supported for this packet type!\n");
 335                 debug_dump_generic_header(ctx, &(h->header_data.data));
 336                 break;
 337         }
 338         debug(ctx, "END\n\n");
 339 }
 340
 341 static inline unsigned int in_80chars(unsigned int i)
 342 {
 343         /* The 3 below is the length of "xx " where xx is the hex string
 344          * representation of a byte */
 345         return ((i + 1) % (80 / 3));
 346 }
 347
 348 static void trace_dump_buffer(am7xxx_context *ctx, const char *message,
 349                               uint8_t *buffer, unsigned int len)
 350 {
 351         unsigned int i;
 352
 353         if (ctx == NULL || buffer == NULL || len == 0)
 354                 return;
 355
 356         trace(ctx, "\n");
 357         if (message)
 358                 trace(ctx, "%s\n", message);
 359
 360         for (i = 0; i < len; i++) {
 361                 trace(ctx, "%02hhX%c", buffer[i], (in_80chars(i) && (i < len - 1)) ? ' ' : '\n');
 362         }
 363         trace(ctx, "\n");
 364 }
 365 #else
 366 static void debug_dump_header(am7xxx_context *ctx, struct am7xxx_header *h)
 367 {
 368         (void)ctx;
 369         (void)h;
 370 }
 371
 372 static void trace_dump_buffer(am7xxx_context *ctx, const char *message,
 373                               uint8_t *buffer, unsigned int len)
 374 {
 375         (void)ctx;
 376         (void)message;
 377         (void)buffer;
 378         (void)len;
 379 }
 380 #endif /* DEBUG */
 381
 382 static int read_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 383 {
 384         int ret;
 385         int transferred;
 386
 387         transferred = 0;
 388         ret = libusb_bulk_transfer(dev->usb_device, 0x81, buffer, len, &transferred, 0);
 389         if (ret != 0 || (unsigned int)transferred != len) {
 390                 error(dev->ctx, "%s. Transferred: %d (expected %u)\n",
 391                       libusb_error_name(ret), transferred, len);
 392                 return ret;
 393         }
 394
 395         trace_dump_buffer(dev->ctx, "<-- received", buffer, len);
 396
 397         return 0;
 398 }
 399
 400 static int send_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 401 {
 402         int ret;
 403         int transferred;
 404
 405         trace_dump_buffer(dev->ctx, "sending -->", buffer, len);
 406
 407         transferred = 0;
 408         ret = libusb_bulk_transfer(dev->usb_device, 0x1, buffer, len, &transferred, 0);
 409         if (ret != 0 || (unsigned int)transferred != len) {
 410                 error(dev->ctx, "%s. Transferred: %d (expected %u)\n",
 411                       libusb_error_name(ret), transferred, len);
 412                 return ret;
 413         }
 414
 415         return 0;
 416 }
 417
 418 static void LIBUSB_CALL send_data_async_complete_cb(struct libusb_transfer *transfer)
 419 {
 420         am7xxx_device *dev = (am7xxx_device *)(transfer->user_data);
 421         int *completed = &(dev->transfer_completed);
 422         int transferred = transfer->actual_length;
 423         int ret;
 424
 425         if (transferred != transfer->length) {
 426                 error(dev->ctx, "transferred: %d (expected %u)\n",
 427                       transferred, transfer->length);
 428         }
 429
 430         switch (transfer->status) {
 431         case LIBUSB_TRANSFER_COMPLETED:
 432                 ret = 0;
 433                 break;
 434         case LIBUSB_TRANSFER_TIMED_OUT:
 435                 ret = LIBUSB_ERROR_TIMEOUT;
 436                 break;
 437         case LIBUSB_TRANSFER_STALL:
 438                 ret = LIBUSB_ERROR_PIPE;
 439                 break;
 440         case LIBUSB_TRANSFER_OVERFLOW:
 441                 ret = LIBUSB_ERROR_OVERFLOW;
 442                 break;
 443         case LIBUSB_TRANSFER_NO_DEVICE:
 444                 ret = LIBUSB_ERROR_NO_DEVICE;
 445                 break;
 446         case LIBUSB_TRANSFER_ERROR:
 447         case LIBUSB_TRANSFER_CANCELLED:
 448                 ret = LIBUSB_ERROR_IO;
 449                 break;
 450         default:
 451                 error(dev->ctx, "unrecognised status code %d", transfer->status);
 452                 ret = LIBUSB_ERROR_OTHER;
 453         }
 454
 455         if (ret < 0)
 456                 error(dev->ctx, "libusb transfer failed: %s",
 457                       libusb_error_name(ret));
 458
 459         libusb_free_transfer(transfer);
 460         transfer = NULL;
 461
 462         *completed = 1;
 463 }
 464
 465 static inline void wait_for_trasfer_completed(am7xxx_device *dev)
 466 {
 467         while (!dev->transfer_completed) {
 468                 int ret = libusb_handle_events_completed(dev->ctx->usb_context,
 469                                                          &(dev->transfer_completed));
 470                 if (ret < 0) {
 471                         if (ret == LIBUSB_ERROR_INTERRUPTED)
 472                                 continue;
 473                         error(dev->ctx, "libusb_handle_events failed: %s, cancelling transfer and retrying",
 474                               libusb_error_name(ret));
 475                         libusb_cancel_transfer(dev->transfer);
 476                         continue;
 477                 }
 478         }
 479 }
 480
 481 static int send_data_async(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 482 {
 483         int ret;
 484         uint8_t *transfer_buffer;
 485
 486         dev->transfer = libusb_alloc_transfer(0);
 487         if (dev->transfer == NULL) {
 488                 error(dev->ctx, "cannot allocate transfer (%s)\n",
 489                       strerror(errno));
 490                 return -ENOMEM;
 491         }
 492
 493         /* Make a copy of the buffer so the caller can safely reuse it just
 494          * after libusb_submit_transfer() has returned. This technique
 495          * requires more dynamic allocations compared to a proper
 496          * double-buffering approach but it takes a lot less code. */
 497         transfer_buffer = malloc(len);
 498         if (transfer_buffer == NULL) {
 499                 error(dev->ctx, "cannot allocate transfer buffer (%s)\n",
 500                       strerror(errno));
 501                 ret = -ENOMEM;
 502                 goto err;
 503         }
 504         memcpy(transfer_buffer, buffer, len);
 505
 506         dev->transfer->flags |= LIBUSB_TRANSFER_FREE_BUFFER;
 507         libusb_fill_bulk_transfer(dev->transfer, dev->usb_device, 0x1,
 508                                   transfer_buffer, len,
 509                                   send_data_async_complete_cb, dev, 0);
 510
 511         /* wait for the previous transfer to complete */
 512         wait_for_trasfer_completed(dev);
 513
 514         trace_dump_buffer(dev->ctx, "sending -->", buffer, len);
 515
 516         dev->transfer_completed = 0;
 517         ret = libusb_submit_transfer(dev->transfer);
 518         if (ret < 0)
 519                 goto err;
 520
 521         return 0;
 522
 523 err:
 524         libusb_free_transfer(dev->transfer);
 525         dev->transfer = NULL;
 526         return ret;
 527 }
 528
 529 static void serialize_header(struct am7xxx_header *h, uint8_t *buffer)
 530 {
 531         uint8_t **buffer_iterator = &buffer;
 532
 533         put_le32(h->packet_type, buffer_iterator);
 534         put_8(h->direction, buffer_iterator);
 535         put_8(h->header_data_len, buffer_iterator);
 536         put_8(h->unknown2, buffer_iterator);
 537         put_8(h->unknown3, buffer_iterator);
 538         put_le32(h->header_data.data.field0, buffer_iterator);
 539         put_le32(h->header_data.data.field1, buffer_iterator);
 540         put_le32(h->header_data.data.field2, buffer_iterator);
 541         put_le32(h->header_data.data.field3, buffer_iterator);
 542 }
 543
 544 static void unserialize_header(uint8_t *buffer, struct am7xxx_header *h)
 545 {
 546         uint8_t **buffer_iterator = &buffer;
 547
 548         h->packet_type = get_le32(buffer_iterator);
 549         h->direction = get_8(buffer_iterator);
 550         h->header_data_len = get_8(buffer_iterator);
 551         h->unknown2 = get_8(buffer_iterator);
 552         h->unknown3 = get_8(buffer_iterator);
 553         h->header_data.data.field0 = get_le32(buffer_iterator);
 554         h->header_data.data.field1 = get_le32(buffer_iterator);
 555         h->header_data.data.field2 = get_le32(buffer_iterator);
 556         h->header_data.data.field3 = get_le32(buffer_iterator);
 557 }
 558
 559 static int read_header(am7xxx_device *dev, struct am7xxx_header *h)
 560 {
 561         int ret;
 562
 563         ret = read_data(dev, dev->buffer, AM7XXX_HEADER_WIRE_SIZE);
 564         if (ret < 0)
 565                 goto out;
 566
 567         unserialize_header(dev->buffer, h);
 568
 569         if (h->direction == AM7XXX_DIRECTION_IN) {
 570                 ret = 0;
 571         } else {
 572                 error(dev->ctx,
 573                       "Expected an AM7XXX_DIRECTION_IN packet, got one with direction = %d. Weird!\n",
 574                       h->direction);
 575                 ret = -EINVAL;
 576         }
 577
 578         debug_dump_header(dev->ctx, h);
 579
 580 out:
 581         return ret;
 582 }
 583
 584 static int send_header(am7xxx_device *dev, struct am7xxx_header *h)
 585 {
 586         int ret;
 587
 588         debug_dump_header(dev->ctx, h);
 589
 590         /* For symmetry with read_header() we should check here for
 591          * h->direction == AM7XXX_DIRECTION_OUT but we just ensure that in all
 592          * the callers and save some cycles here.
 593          */
 594
 595         serialize_header(h, dev->buffer);
 596
 597         ret = send_data(dev, dev->buffer, AM7XXX_HEADER_WIRE_SIZE);
 598         if (ret < 0)
 599                 error(dev->ctx, "failed to send data\n");
 600
 601         return ret;
 602 }
 603
 604 static int send_command(am7xxx_device *dev, am7xxx_packet_type type)
 605 {
 606         struct am7xxx_header h = {
 607                 .packet_type     = type,
 608                 .direction       = AM7XXX_DIRECTION_OUT,
 609                 .header_data_len = 0x00,
 610                 .unknown2        = 0x3e,
 611                 .unknown3        = 0x10,
 612                 .header_data = {
 613                         .data = {
 614                                 .field0 = 0,
 615                                 .field1 = 0,
 616                                 .field2 = 0,
 617                                 .field3 = 0,
 618                         },
 619                 },
 620         };
 621
 622         return send_header(dev, &h);
 623 }
 624
 625
 626 /* When level == AM7XXX_LOG_FATAL do not check the log_level from the context
 627  * and print the message unconditionally, this makes it possible to print
 628  * fatal messages even early on initialization, before the context has been
 629  * set up */
 630 static void log_message(am7xxx_context *ctx,
 631                         int level,
 632                         const char *function_name,
 633                         int line,
 634                         const char *fmt,
 635                         ...)
 636 {
 637         va_list ap;
 638
 639         if (level == AM7XXX_LOG_FATAL || (ctx && level <= ctx->log_level)) {
 640                 if (function_name) {
 641                         fprintf(stderr, "%s", function_name);
 642                         if (line)
 643                                 fprintf(stderr, "[%d]", line);
 644                         fprintf(stderr, ": ");
 645                 }
 646
 647                 va_start(ap, fmt);
 648                 vfprintf(stderr, fmt, ap);
 649                 va_end(ap);
 650         }
 651
 652         return;
 653 }
 654
 655 static am7xxx_device *add_new_device(am7xxx_context *ctx,
 656                                      const struct am7xxx_usb_device_descriptor *desc)
 657 {
 658         am7xxx_device **devices_list;
 659         am7xxx_device *new_device;
 660
 661         if (ctx == NULL) {
 662                 fatal("context must not be NULL!\n");
 663                 return NULL;
 664         }
 665
 666         new_device = malloc(sizeof(*new_device));
 667         if (new_device == NULL) {
 668                 debug(ctx, "cannot allocate a new device (%s)\n", strerror(errno));
 669                 return NULL;
 670         }
 671         memset(new_device, 0, sizeof(*new_device));
 672
 673         new_device->ctx = ctx;
 674         new_device->desc = desc;
 675         new_device->transfer_completed = 1;
 676
 677         devices_list = &(ctx->devices_list);
 678
 679         if (*devices_list == NULL) {
 680                 *devices_list = new_device;
 681         } else {
 682                 am7xxx_device *prev = *devices_list;
 683                 while (prev->next)
 684                         prev = prev->next;
 685                 prev->next = new_device;
 686         }
 687         return new_device;
 688 }
 689
 690 static am7xxx_device *find_device(am7xxx_context *ctx,
 691                                   unsigned int device_index)
 692 {
 693         unsigned int i = 0;
 694         am7xxx_device *current;
 695
 696         if (ctx == NULL) {
 697                 fatal("context must not be NULL!\n");
 698                 return NULL;
 699         }
 700
 701         current = ctx->devices_list;
 702         while (current && i++ < device_index)
 703                 current = current->next;
 704
 705         return current;
 706 }
 707
 708 static int open_device(am7xxx_context *ctx,
 709                        unsigned int device_index,
 710                        libusb_device *usb_dev,
 711                        am7xxx_device **dev)
 712 {
 713         int ret;
 714         int current_configuration;
 715
 716         *dev = find_device(ctx, device_index);
 717         if (*dev == NULL) {
 718                 ret = -ENODEV;
 719                 goto out;
 720         }
 721
 722         /* the usb device has already been opened */
 723         if ((*dev)->usb_device) {
 724                 ret = 1;
 725                 goto out;
 726         }
 727
 728         ret = libusb_open(usb_dev, &((*dev)->usb_device));
 729         if (ret < 0) {
 730                 debug(ctx, "libusb_open failed: %s\n", libusb_error_name(ret));
 731                 goto out;
 732         }
 733
 734         /* XXX, the device is now open, if any of the calls below fail we need
 735          * to close it again before bailing out.
 736          */
 737
 738         current_configuration = -1;
 739         ret = libusb_get_configuration((*dev)->usb_device,
 740                                        &current_configuration);
 741         if (ret < 0) {
 742                 debug(ctx, "libusb_get_configuration failed: %s\n",
 743                       libusb_error_name(ret));
 744                 goto out_libusb_close;
 745         }
 746
 747         if (current_configuration != (*dev)->desc->configuration) {
 748                 /*
 749                  * In principle, before setting a new configuration, kernel
 750                  * drivers should be detached from _all_ interfaces; for
 751                  * example calling something like the following "invented"
 752                  * function _before_ setting the new configuration:
 753                  *
 754                  *   libusb_detach_all_kernel_drivers((*dev)->usb_device);
 755                  *
 756                  * However, in practice, this is not necessary for most
 757                  * devices as they have only one configuration.
 758                  *
 759                  * When a device only has one configuration:
 760                  *
 761                  *   - if there was a kernel driver bound to the device, it
 762                  *     had already set the configuration and the call below
 763                  *     will be skipped;
 764                  *
 765                  *   - if no kernel driver was bound to the device, the call
 766                  *     below will suceed.
 767                  */
 768                 ret = libusb_set_configuration((*dev)->usb_device,
 769                                                (*dev)->desc->configuration);
 770                 if (ret < 0) {
 771                         debug(ctx, "libusb_set_configuration failed: %s\n",
 772                               libusb_error_name(ret));
 773                         debug(ctx, "Cannot set configuration %hhu\n",
 774                               (*dev)->desc->configuration);
 775                         goto out_libusb_close;
 776                 }
 777         }
 778
 779         libusb_set_auto_detach_kernel_driver((*dev)->usb_device, 1);
 780
 781         ret = libusb_claim_interface((*dev)->usb_device,
 782                                      (*dev)->desc->interface_number);
 783         if (ret < 0) {
 784                 debug(ctx, "libusb_claim_interface failed: %s\n",
 785                       libusb_error_name(ret));
 786                 debug(ctx, "Cannot claim interface %hhu\n",
 787                       (*dev)->desc->interface_number);
 788                 goto out_libusb_close;
 789         }
 790
 791         /* Checking that the configuration has not changed, as suggested in
 792          * http://libusb.sourceforge.net/api-1.0/caveats.html
 793          */
 794         current_configuration = -1;
 795         ret = libusb_get_configuration((*dev)->usb_device,
 796                                        &current_configuration);
 797         if (ret < 0) {
 798                 debug(ctx, "libusb_get_configuration after claim failed: %s\n",
 799                       libusb_error_name(ret));
 800                 goto out_libusb_release_interface;
 801         }
 802
 803         if (current_configuration != (*dev)->desc->configuration) {
 804                 debug(ctx, "libusb configuration changed (expected: %hhu, current: %d)\n",
 805                       (*dev)->desc->configuration, current_configuration);
 806                 ret = -EINVAL;
 807                 goto out_libusb_release_interface;
 808         }
 809 out:
 810         return ret;
 811
 812 out_libusb_release_interface:
 813         libusb_release_interface((*dev)->usb_device,
 814                                  (*dev)->desc->interface_number);
 815 out_libusb_close:
 816         libusb_close((*dev)->usb_device);
 817         (*dev)->usb_device = NULL;
 818         return ret;
 819 }
 820
 821 typedef enum {
 822         SCAN_OP_BUILD_DEVLIST,
 823         SCAN_OP_OPEN_DEVICE,
 824 } scan_op;
 825
 826 /**
 827  * This is where the central logic of multi-device support is.
 828  *
 829  * When 'op' == SCAN_OP_BUILD_DEVLIST the parameters 'open_device_index' and
 830  * 'dev' are ignored; the function returns 0 on success or a negative value
 831  * on error.
 832  *
 833  * When 'op' == SCAN_OP_OPEN_DEVICE the function opens the supported USB
 834  * device with index 'open_device_index' and returns the correspondent
 835  * am7xxx_device in the 'dev' parameter; the function returns the value from
 836  * open_device(), which is 0 on success, 1 if the device was already open or
 837  * a negative value on error.
 838  *
 839  * NOTES:
 840  * if scan_devices() fails when called with 'op' == SCAN_OP_BUILD_DEVLIST,
 841  * the caller might want to call am7xxx_shutdown() in order to remove
 842  * devices possibly added before the failure.
 843  */
 844 static int scan_devices(am7xxx_context *ctx, scan_op op,
 845                         unsigned int open_device_index, am7xxx_device **dev)
 846 {
 847         ssize_t num_devices;
 848         libusb_device **list;
 849         unsigned int current_index;
 850         int i;
 851         int ret;
 852
 853         if (ctx == NULL) {
 854                 fatal("context must not be NULL!\n");
 855                 return -EINVAL;
 856         }
 857         if (op == SCAN_OP_BUILD_DEVLIST && ctx->devices_list != NULL) {
 858                 error(ctx, "device scan done already? Abort!\n");
 859                 return -EINVAL;
 860         }
 861
 862         num_devices = libusb_get_device_list(ctx->usb_context, &list);
 863         if (num_devices < 0) {
 864                 ret = -ENODEV;
 865                 goto out;
 866         }
 867
 868         current_index = 0;
 869         for (i = 0; i < num_devices; i++) {
 870                 struct libusb_device_descriptor desc;
 871                 unsigned int j;
 872
 873                 ret = libusb_get_device_descriptor(list[i], &desc);
 874                 if (ret < 0)
 875                         continue;
 876
 877                 for (j = 0; j < ARRAY_SIZE(supported_devices); j++) {
 878                         if (desc.idVendor == supported_devices[j].vendor_id &&
 879                             desc.idProduct == supported_devices[j].product_id) {
 880
 881                                 if (op == SCAN_OP_BUILD_DEVLIST) {
 882                                         am7xxx_device *new_device;
 883                                         info(ctx, "am7xxx device found, index: %d, name: %s\n",
 884                                              current_index,
 885                                              supported_devices[j].name);
 886                                         new_device = add_new_device(ctx, &supported_devices[j]);
 887                                         if (new_device == NULL) {
 888                                                 /* XXX, the caller may want
 889                                                  * to call am7xxx_shutdown() if
 890                                                  * we fail here, as we may have
 891                                                  * added some devices already
 892                                                  */
 893                                                 debug(ctx, "Cannot create a new device\n");
 894                                                 ret = -ENODEV;
 895                                                 goto out;
 896                                         }
 897                                 } else if (op == SCAN_OP_OPEN_DEVICE &&
 898                                            current_index == open_device_index) {
 899
 900                                         ret = open_device(ctx,
 901                                                           open_device_index,
 902                                                           list[i],
 903                                                           dev);
 904                                         if (ret < 0)
 905                                                 debug(ctx, "open_device failed\n");
 906
 907                                         /* exit the loop unconditionally after
 908                                          * attempting to open the device
 909                                          * requested by the user */
 910                                         goto out;
 911                                 }
 912                                 current_index++;
 913                         }
 914                 }
 915         }
 916
 917         /* if we made it up to here when op == SCAN_OP_OPEN_DEVICE,
 918          * no devices to open had been found. */
 919         if (op == SCAN_OP_OPEN_DEVICE) {
 920                 error(ctx, "Cannot find any device to open\n");
 921                 ret = -ENODEV;
 922                 goto out;
 923         }
 924
 925         /* everything went fine when building the device list */
 926         ret = 0;
 927 out:
 928         libusb_free_device_list(list, 1);
 929         return ret;
 930 }
 931
 932 /* Device specific operations */
 933
 934 static int default_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power)
 935 {
 936         int ret;
 937         struct am7xxx_header h = {
 938                 .packet_type     = AM7XXX_PACKET_TYPE_POWER,
 939                 .direction       = AM7XXX_DIRECTION_OUT,
 940                 .header_data_len = sizeof(struct am7xxx_power_header),
 941                 .unknown2        = 0x3e,
 942                 .unknown3        = 0x10,
 943         };
 944
 945         switch(power) {
 946         case AM7XXX_POWER_OFF:
 947                 h.header_data.power.bit2 = 0;
 948                 h.header_data.power.bit1 = 0;
 949                 h.header_data.power.bit0 = 0;
 950                 break;
 951
 952         case AM7XXX_POWER_LOW:
 953                 h.header_data.power.bit2 = 0;
 954                 h.header_data.power.bit1 = 0;
 955                 h.header_data.power.bit0 = 1;
 956                 break;
 957
 958         case AM7XXX_POWER_MIDDLE:
 959                 h.header_data.power.bit2 = 0;
 960                 h.header_data.power.bit1 = 1;
 961                 h.header_data.power.bit0 = 0;
 962                 break;
 963
 964         case AM7XXX_POWER_HIGH:
 965                 h.header_data.power.bit2 = 0;
 966                 h.header_data.power.bit1 = 1;
 967                 h.header_data.power.bit0 = 1;
 968                 break;
 969
 970         case AM7XXX_POWER_TURBO:
 971                 h.header_data.power.bit2 = 1;
 972                 h.header_data.power.bit1 = 0;
 973                 h.header_data.power.bit0 = 0;
 974                 break;
 975
 976         default:
 977                 error(dev->ctx, "Unsupported power mode.\n");
 978                 return -EINVAL;
 979         };
 980
 981         ret = send_header(dev, &h);
 982         if (ret < 0)
 983                 return ret;
 984
 985         return 0;
 986 }
 987
 988 static int picopix_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power)
 989 {
 990         switch(power) {
 991         case AM7XXX_POWER_LOW:
 992                 return send_command(dev, AM7XXX_PACKET_TYPE_PICOPIX_POWER_LOW);
 993
 994         case AM7XXX_POWER_MIDDLE:
 995                 return send_command(dev, AM7XXX_PACKET_TYPE_PICOPIX_POWER_MEDIUM);
 996
 997         case AM7XXX_POWER_HIGH:
 998                 return send_command(dev, AM7XXX_PACKET_TYPE_PICOPIX_POWER_HIGH);
 999
1000         case AM7XXX_POWER_OFF:
1001         case AM7XXX_POWER_TURBO:
1002         default:
1003                 error(dev->ctx, "Unsupported power mode.\n");
1004                 return -EINVAL;
1005         };
1006 }
1007
1008 static int default_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom)
1009 {
1010         int ret;
1011         struct am7xxx_header h = {
1012                 .packet_type     = AM7XXX_PACKET_TYPE_ZOOM,
1013                 .direction       = AM7XXX_DIRECTION_OUT,
1014                 .header_data_len = sizeof(struct am7xxx_zoom_header),
1015                 .unknown2        = 0x3e,
1016                 .unknown3        = 0x10,
1017         };
1018
1019         switch(zoom) {
1020         case AM7XXX_ZOOM_ORIGINAL:
1021                 h.header_data.zoom.bit1 = 0;
1022                 h.header_data.zoom.bit0 = 0;
1023                 break;
1024
1025         case AM7XXX_ZOOM_H:
1026                 h.header_data.zoom.bit1 = 0;
1027                 h.header_data.zoom.bit0 = 1;
1028                 break;
1029
1030         case AM7XXX_ZOOM_H_V:
1031                 h.header_data.zoom.bit1 = 1;
1032                 h.header_data.zoom.bit0 = 0;
1033                 break;
1034
1035         case AM7XXX_ZOOM_TEST:
1036                 h.header_data.zoom.bit1 = 1;
1037                 h.header_data.zoom.bit0 = 1;
1038                 break;
1039
1040         case AM7XXX_ZOOM_TELE:
1041         default:
1042                 error(dev->ctx, "Unsupported zoom mode.\n");
1043                 return -EINVAL;
1044         };
1045
1046         ret = send_header(dev, &h);
1047         if (ret < 0)
1048                 return ret;
1049
1050         return 0;
1051 }
1052
1053 static int picopix_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom)
1054 {
1055         int ret;
1056         am7xxx_packet_type packet_type;
1057
1058         switch(zoom) {
1059         case AM7XXX_ZOOM_ORIGINAL:
1060                 packet_type = AM7XXX_PACKET_TYPE_PICOPIX_DISABLE_TI;
1061                 break;
1062
1063         case AM7XXX_ZOOM_TELE:
1064                 packet_type = AM7XXX_PACKET_TYPE_PICOPIX_ENABLE_TI;
1065                 break;
1066
1067         case AM7XXX_ZOOM_H:
1068         case AM7XXX_ZOOM_H_V:
1069         case AM7XXX_ZOOM_TEST:
1070         default:
1071                 error(dev->ctx, "Unsupported zoom mode.\n");
1072                 return -EINVAL;
1073         };
1074
1075         ret = send_command(dev, packet_type);
1076         if (ret < 0)
1077                 return ret;
1078
1079         /* The Windows drivers wait for 100ms and send the same command again,
1080          * probably to overcome a firmware deficiency */
1081         ret = msleep(100);
1082         if (ret < 0)
1083                 return ret;
1084
1085         return send_command(dev, packet_type);
1086 }
1087
1088 /* Public API */
1089
1090 AM7XXX_PUBLIC int am7xxx_init(am7xxx_context **ctx)
1091 {
1092         int ret;
1093
1094         *ctx = malloc(sizeof(**ctx));
1095         if (*ctx == NULL) {
1096                 fatal("cannot allocate the context (%s)\n", strerror(errno));
1097                 return -ENOMEM;
1098         }
1099         memset(*ctx, 0, sizeof(**ctx));
1100
1101         /* Set the highest log level during initialization */
1102         (*ctx)->log_level = AM7XXX_LOG_TRACE;
1103
1104         ret = libusb_init(&((*ctx)->usb_context));
1105         if (ret < 0) {
1106                 error(*ctx, "libusb_init failed: %s\n", libusb_error_name(ret));
1107                 goto out_free_context;
1108         }
1109
1110         libusb_set_debug((*ctx)->usb_context, LIBUSB_LOG_LEVEL_INFO);
1111
1112         ret = scan_devices(*ctx, SCAN_OP_BUILD_DEVLIST , 0, NULL);
1113         if (ret < 0) {
1114                 error(*ctx, "scan_devices() failed\n");
1115                 am7xxx_shutdown(*ctx);
1116                 goto out;
1117         }
1118
1119         /* Set a quieter log level as default for normal operation */
1120         (*ctx)->log_level = AM7XXX_LOG_ERROR;
1121         return 0;
1122
1123 out_free_context:
1124         free(*ctx);
1125         *ctx = NULL;
1126 out:
1127         return ret;
1128 }
1129
1130 AM7XXX_PUBLIC void am7xxx_shutdown(am7xxx_context *ctx)
1131 {
1132         am7xxx_device *current;
1133
1134         if (ctx == NULL) {
1135                 fatal("context must not be NULL!\n");
1136                 return;
1137         }
1138
1139         current = ctx->devices_list;
1140         while (current) {
1141                 am7xxx_device *next = current->next;
1142                 am7xxx_close_device(current);
1143                 free(current->device_info);
1144                 free(current);
1145                 current = next;
1146         }
1147
1148         libusb_exit(ctx->usb_context);
1149         free(ctx);
1150         ctx = NULL;
1151 }
1152
1153 AM7XXX_PUBLIC void am7xxx_set_log_level(am7xxx_context *ctx, am7xxx_log_level log_level)
1154 {
1155         ctx->log_level = log_level;
1156 }
1157
1158 AM7XXX_PUBLIC int am7xxx_open_device(am7xxx_context *ctx, am7xxx_device **dev,
1159                        unsigned int device_index)
1160 {
1161         int ret;
1162
1163         if (ctx == NULL) {
1164                 fatal("context must not be NULL!\n");
1165                 return -EINVAL;
1166         }
1167
1168         ret = scan_devices(ctx, SCAN_OP_OPEN_DEVICE, device_index, dev);
1169         if (ret < 0) {
1170                 errno = ENODEV;
1171                 goto out;
1172         } else if (ret > 0) {
1173                 warning(ctx, "device %d already open\n", device_index);
1174                 errno = EBUSY;
1175                 ret = -EBUSY;
1176                 goto out;
1177         }
1178
1179         /* Philips/Sagemcom PicoPix projectors require that the DEVINFO packet
1180          * is the first one to be sent to the device in order for it to
1181          * successfully return the correct device information.
1182          *
1183          * NOTE: am7xxx_get_device_info() will fetch the actual device info
1184          * from the device only the very first time it's called for a given
1185          * device, otherwise, it'll return a cached version of the device info
1186          * (from a previous call to am7xxx_open_device(), for instance).
1187          */
1188         ret = am7xxx_get_device_info(*dev, NULL);
1189         if (ret < 0)
1190                 error(ctx, "cannot get device info\n");
1191
1192 out:
1193         return ret;
1194 }
1195
1196 AM7XXX_PUBLIC int am7xxx_close_device(am7xxx_device *dev)
1197 {
1198         if (dev == NULL) {
1199                 fatal("dev must not be NULL!\n");
1200                 return -EINVAL;
1201         }
1202         if (dev->usb_device) {
1203                 wait_for_trasfer_completed(dev);
1204                 libusb_release_interface(dev->usb_device, dev->desc->interface_number);
1205                 libusb_close(dev->usb_device);
1206                 dev->usb_device = NULL;
1207         }
1208         return 0;
1209 }
1210
1211 AM7XXX_PUBLIC int am7xxx_get_device_info(am7xxx_device *dev,
1212                            am7xxx_device_info *device_info)
1213 {
1214         int ret;
1215         struct am7xxx_header h;
1216
1217         /* if there is a cached copy of the device info, just return that */
1218         if (dev->device_info)
1219                 goto return_value;
1220
1221         ret = send_command(dev, AM7XXX_PACKET_TYPE_DEVINFO);
1222         if (ret < 0)
1223                 return ret;
1224
1225         memset(&h, 0, sizeof(h));
1226         ret = read_header(dev, &h);
1227         if (ret < 0)
1228                 return ret;
1229
1230         if (h.packet_type != AM7XXX_PACKET_TYPE_DEVINFO) {
1231                 error(dev->ctx, "expected packet type: %d, got %d instead!\n",
1232                       AM7XXX_PACKET_TYPE_DEVINFO, h.packet_type);
1233                 errno = ENOTSUP;
1234                 return -ENOTSUP;
1235         }
1236
1237         dev->device_info = malloc(sizeof(*dev->device_info));
1238         if (dev->device_info == NULL) {
1239                 error(dev->ctx, "cannot allocate a device info (%s)\n",
1240                        strerror(errno));
1241                 return -ENOMEM;
1242         }
1243         memset(dev->device_info, 0, sizeof(*dev->device_info));
1244
1245         dev->device_info->native_width = h.header_data.devinfo.native_width;
1246         dev->device_info->native_height = h.header_data.devinfo.native_height;
1247 #if 0
1248         /* No reason to expose these in the public API until we know what they mean */
1249         dev->device_info->unknown0 = h.header_data.devinfo.unknown0;
1250         dev->device_info->unknown1 = h.header_data.devinfo.unknown1;
1251 #endif
1252
1253 return_value:
1254         if (device_info)
1255                 memcpy(device_info, dev->device_info, sizeof(*device_info));
1256         return 0;
1257 }
1258
1259 AM7XXX_PUBLIC int am7xxx_calc_scaled_image_dimensions(am7xxx_device *dev,
1260                                         unsigned int upscale,
1261                                         unsigned int original_width,
1262                                         unsigned int original_height,
1263                                         unsigned int *scaled_width,
1264                                         unsigned int *scaled_height)
1265 {
1266         am7xxx_device_info device_info;
1267         float width_ratio;
1268         float height_ratio;
1269         int ret;
1270
1271         ret = am7xxx_get_device_info(dev, &device_info);
1272         if (ret < 0) {
1273                 error(dev->ctx, "cannot get device info\n");
1274                 return ret;
1275         }
1276
1277         /*
1278          * Check if we need to rescale; if the input image fits the native
1279          * dimensions there is no need to, unless we want to upscale.
1280          */
1281         if (!upscale &&
1282             original_width <= device_info.native_width &&
1283             original_height <= device_info.native_height ) {
1284                 debug(dev->ctx, "CASE 0, no rescaling, the original image fits already\n");
1285                 *scaled_width = original_width;
1286                 *scaled_height = original_height;
1287                 return 0;
1288         }
1289
1290         /* Input dimensions relative to the device native dimensions */
1291         width_ratio =  (float)original_width / device_info.native_width;
1292         height_ratio = (float)original_height / device_info.native_height;
1293
1294         if (width_ratio > height_ratio) {
1295                 /*
1296                  * The input is proportionally "wider" than the device viewport
1297                  * so its height needs to be adjusted
1298                  */
1299                 debug(dev->ctx, "CASE 1, original image wider, adjust the scaled height\n");
1300                 *scaled_width = device_info.native_width;
1301                 *scaled_height = (unsigned int)lroundf(original_height / width_ratio);
1302         } else if (width_ratio < height_ratio) {
1303                 /*
1304                  * The input is proportionally "taller" than the device viewport
1305                  * so its width needs to be adjusted
1306                  */
1307                 debug(dev->ctx, "CASE 2 original image taller, adjust the scaled width\n");
1308                 *scaled_width = (unsigned int)lroundf(original_width / height_ratio);
1309                 *scaled_height = device_info.native_height;
1310         } else {
1311                 debug(dev->ctx, "CASE 3, just rescale, same aspect ratio already\n");
1312                 *scaled_width = device_info.native_width;
1313                 *scaled_height = device_info.native_height;
1314         }
1315         debug(dev->ctx, "scaled dimensions: %dx%d\n", *scaled_width, *scaled_height);
1316
1317         return 0;
1318 }
1319
1320 AM7XXX_PUBLIC int am7xxx_send_image(am7xxx_device *dev,
1321                       am7xxx_image_format format,
1322                       unsigned int width,
1323                       unsigned int height,
1324                       uint8_t *image,
1325                       unsigned int image_size)
1326 {
1327         int ret;
1328         struct am7xxx_header h = {
1329                 .packet_type     = AM7XXX_PACKET_TYPE_IMAGE,
1330                 .direction       = AM7XXX_DIRECTION_OUT,
1331                 .header_data_len = sizeof(struct am7xxx_image_header),
1332                 .unknown2        = 0x3e,
1333                 .unknown3        = 0x10,
1334                 .header_data = {
1335                         .image = {
1336                                 .format     = format,
1337                                 .width      = width,
1338                                 .height     = height,
1339                                 .image_size = image_size,
1340                         },
1341                 },
1342         };
1343
1344         ret = send_header(dev, &h);
1345         if (ret < 0)
1346                 return ret;
1347
1348         if (image == NULL || image_size == 0) {
1349                 warning(dev->ctx, "Not sending any data, check the 'image' or 'image_size' parameters\n");
1350                 return 0;
1351         }
1352
1353         return send_data(dev, image, image_size);
1354 }
1355
1356 AM7XXX_PUBLIC int am7xxx_send_image_async(am7xxx_device *dev,
1357                                           am7xxx_image_format format,
1358                                           unsigned int width,
1359                                           unsigned int height,
1360                                           uint8_t *image,
1361                                           unsigned int image_size)
1362 {
1363         int ret;
1364         struct am7xxx_header h = {
1365                 .packet_type     = AM7XXX_PACKET_TYPE_IMAGE,
1366                 .direction       = AM7XXX_DIRECTION_OUT,
1367                 .header_data_len = sizeof(struct am7xxx_image_header),
1368                 .unknown2        = 0x3e,
1369                 .unknown3        = 0x10,
1370                 .header_data = {
1371                         .image = {
1372                                 .format     = format,
1373                                 .width      = width,
1374                                 .height     = height,
1375                                 .image_size = image_size,
1376                         },
1377                 },
1378         };
1379
1380         ret = send_header(dev, &h);
1381         if (ret < 0)
1382                 return ret;
1383
1384         if (image == NULL || image_size == 0) {
1385                 warning(dev->ctx, "Not sending any data, check the 'image' or 'image_size' parameters\n");
1386                 return 0;
1387         }
1388
1389         return send_data_async(dev, image, image_size);
1390 }
1391
1392 AM7XXX_PUBLIC int am7xxx_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power)
1393 {
1394         if (dev->desc->ops.set_power_mode == NULL) {
1395                 warning(dev->ctx,
1396                         "setting power mode is unsupported on this device\n");
1397                 return 0;
1398         }
1399
1400         return dev->desc->ops.set_power_mode(dev, power);
1401 }
1402
1403 AM7XXX_PUBLIC int am7xxx_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom)
1404 {
1405         if (dev->desc->ops.set_zoom_mode == NULL) {
1406                 warning(dev->ctx,
1407                         "setting zoom mode is unsupported on this device\n");
1408                 return 0;
1409         }
1410
1411         return dev->desc->ops.set_zoom_mode(dev, zoom);
1412 }