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 /*
  42  * Fix printf format when compiling for Windows with MinGW, see:
  43  * https://sourceforge.net/p/mingw-w64/wiki2/gnu%20printf/
  44  */
  45 #ifdef __MINGW_PRINTF_FORMAT
  46         #define AM7XXX_PRINTF_FORMAT __MINGW_PRINTF_FORMAT
  47 #else
  48         #define AM7XXX_PRINTF_FORMAT printf
  49 #endif
  50
  51 /* Control shared library symbols visibility */
  52 #if defined _WIN32 || defined __CYGWIN__
  53         #define AM7XXX_PUBLIC __declspec(dllexport)
  54         #define AM7XXX_LOCAL
  55 #else
  56         #if __GNUC__ >= 4
  57                 #define AM7XXX_PUBLIC __attribute__ ((visibility ("default")))
  58                 #define AM7XXX_LOCAL  __attribute__ ((visibility ("hidden")))
  59         #else
  60                 #define AM7XXX_PUBLIC
  61                 #define AM7XXX_LOCAL
  62         #endif
  63 #endif
  64
  65 static void log_message(am7xxx_context *ctx,
  66                         int level,
  67                         const char *function_name,
  68                         int line,
  69                         const char *fmt,
  70                         ...) __attribute__ ((format (AM7XXX_PRINTF_FORMAT, 5, 6)));
  71
  72 #define fatal(...)        log_message(NULL, AM7XXX_LOG_FATAL,   __func__, __LINE__, __VA_ARGS__)
  73 #define error(ctx, ...)   log_message(ctx,  AM7XXX_LOG_ERROR,   __func__, __LINE__, __VA_ARGS__)
  74 #define warning(ctx, ...) log_message(ctx,  AM7XXX_LOG_WARNING, __func__, 0,        __VA_ARGS__)
  75 #define info(ctx, ...)    log_message(ctx,  AM7XXX_LOG_INFO,    __func__, 0,        __VA_ARGS__)
  76 #define debug(ctx, ...)   log_message(ctx,  AM7XXX_LOG_DEBUG,   __func__, 0,        __VA_ARGS__)
  77 #define trace(ctx, ...)   log_message(ctx,  AM7XXX_LOG_TRACE,   NULL,     0,        __VA_ARGS__)
  78
  79 struct am7xxx_ops {
  80         int (*set_power_mode)(am7xxx_device *dev, am7xxx_power_mode power);
  81         int (*set_zoom_mode)(am7xxx_device *dev, am7xxx_zoom_mode zoom);
  82 };
  83
  84 struct am7xxx_usb_device_descriptor {
  85         const char *name;
  86         uint16_t vendor_id;
  87         uint16_t product_id;
  88         uint8_t configuration;    /* The bConfigurationValue of the device */
  89         uint8_t interface_number; /* The bInterfaceNumber of the device */
  90         struct am7xxx_ops ops;
  91 };
  92
  93 static int default_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power);
  94 static int picopix_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power);
  95 static int default_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom);
  96 static int picopix_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom);
  97
  98 #define DEFAULT_OPS { \
  99         .set_power_mode = default_set_power_mode, \
 100         .set_zoom_mode = default_set_zoom_mode, \
 101 }
 102
 103 static const struct am7xxx_usb_device_descriptor supported_devices[] = {
 104         {
 105                 .name       = "Acer C110",
 106                 .vendor_id  = 0x1de1,
 107                 .product_id = 0xc101,
 108                 .configuration    = 2,
 109                 .interface_number = 0,
 110                 .ops = DEFAULT_OPS,
 111         },
 112         {
 113                 .name       = "Acer C112",
 114                 .vendor_id  = 0x1de1,
 115                 .product_id = 0x5501,
 116                 .configuration    = 2,
 117                 .interface_number = 0,
 118                 .ops = DEFAULT_OPS,
 119         },
 120         {
 121                 .name       ="Aiptek PocketCinema T25",
 122                 .vendor_id  = 0x08ca,
 123                 .product_id = 0x2144,
 124                 .configuration    = 2,
 125                 .interface_number = 0,
 126                 .ops = DEFAULT_OPS,
 127         },
 128         {
 129                 .name       = "Philips/Sagemcom PicoPix 1020",
 130                 .vendor_id  = 0x21e7,
 131                 .product_id = 0x000e,
 132                 .configuration    = 2,
 133                 .interface_number = 0,
 134                 .ops = DEFAULT_OPS,
 135         },
 136         {
 137                 .name       = "Philips/Sagemcom PicoPix 2055",
 138                 .vendor_id  = 0x21e7,
 139                 .product_id = 0x0016,
 140                 .configuration    = 2,
 141                 .interface_number = 0,
 142                 .ops = {
 143                         .set_power_mode = picopix_set_power_mode,
 144                         .set_zoom_mode = picopix_set_zoom_mode,
 145                 },
 146         },
 147         {
 148                 .name       = "Philips/Sagemcom PicoPix 2330",
 149                 .vendor_id  = 0x21e7,
 150                 .product_id = 0x0019,
 151                 .configuration    = 1,
 152                 .interface_number = 0,
 153         },
 154 };
 155
 156 /* The header size on the wire is known to be always 24 bytes, regardless of
 157  * the memory configuration enforced by different architectures or compilers
 158  * for struct am7xxx_header
 159  */
 160 #define AM7XXX_HEADER_WIRE_SIZE 24
 161
 162 struct _am7xxx_device {
 163         libusb_device_handle *usb_device;
 164         struct libusb_transfer *transfer;
 165         int transfer_completed;
 166         uint8_t buffer[AM7XXX_HEADER_WIRE_SIZE];
 167         am7xxx_device_info *device_info;
 168         am7xxx_context *ctx;
 169         const struct am7xxx_usb_device_descriptor *desc;
 170         am7xxx_device *next;
 171 };
 172
 173 struct _am7xxx_context {
 174         libusb_context *usb_context;
 175         int log_level;
 176         am7xxx_device *devices_list;
 177 };
 178
 179 typedef enum {
 180         AM7XXX_PACKET_TYPE_DEVINFO = 0x01,
 181         AM7XXX_PACKET_TYPE_IMAGE   = 0x02,
 182         AM7XXX_PACKET_TYPE_POWER   = 0x04,
 183         AM7XXX_PACKET_TYPE_ZOOM    = 0x05,
 184         AM7XXX_PACKET_TYPE_PICOPIX_POWER_LOW    = 0x15,
 185         AM7XXX_PACKET_TYPE_PICOPIX_POWER_MEDIUM = 0x16,
 186         AM7XXX_PACKET_TYPE_PICOPIX_POWER_HIGH   = 0x17,
 187         AM7XXX_PACKET_TYPE_PICOPIX_ENABLE_TI    = 0x18,
 188         AM7XXX_PACKET_TYPE_PICOPIX_DISABLE_TI   = 0x19,
 189 } am7xxx_packet_type;
 190
 191 struct am7xxx_generic_header {
 192         uint32_t field0;
 193         uint32_t field1;
 194         uint32_t field2;
 195         uint32_t field3;
 196 };
 197
 198 struct am7xxx_devinfo_header {
 199         uint32_t native_width;
 200         uint32_t native_height;
 201         uint32_t unknown0;
 202         uint32_t unknown1;
 203 };
 204
 205 struct am7xxx_image_header {
 206         uint32_t format;
 207         uint32_t width;
 208         uint32_t height;
 209         uint32_t image_size;
 210 };
 211
 212 struct am7xxx_power_header {
 213         uint32_t bit2;
 214         uint32_t bit1;
 215         uint32_t bit0;
 216 };
 217
 218 struct am7xxx_zoom_header {
 219         uint32_t bit1;
 220         uint32_t bit0;
 221 };
 222
 223 /*
 224  * Examples of packet headers:
 225  *
 226  * Image header:
 227  * 02 00 00 00 00 10 3e 10 01 00 00 00 20 03 00 00 e0 01 00 00 53 E8 00 00
 228  *
 229  * Power header:
 230  * 04 00 00 00 00 0c ff ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 231  */
 232
 233 /* Direction of the communication from the host point of view */
 234 #define AM7XXX_DIRECTION_OUT 0 /* host -> device */
 235 #define AM7XXX_DIRECTION_IN  1 /* host <- device */
 236
 237 struct am7xxx_header {
 238         uint32_t packet_type;
 239         uint8_t direction;
 240         uint8_t header_data_len;
 241         uint8_t unknown2;
 242         uint8_t unknown3;
 243         union {
 244                 struct am7xxx_generic_header data;
 245                 struct am7xxx_devinfo_header devinfo;
 246                 struct am7xxx_image_header image;
 247                 struct am7xxx_power_header power;
 248                 struct am7xxx_zoom_header zoom;
 249         } header_data;
 250 };
 251
 252
 253 #ifdef DEBUG
 254 static void debug_dump_generic_header(am7xxx_context *ctx, struct am7xxx_generic_header *g)
 255 {
 256         if (ctx == NULL || g == NULL)
 257                 return;
 258
 259         debug(ctx, "Generic header:\n");
 260         debug(ctx, "\tfield0:  0x%08x (%u)\n", g->field0, g->field0);
 261         debug(ctx, "\tfield1:  0x%08x (%u)\n", g->field1, g->field1);
 262         debug(ctx, "\tfield2:  0x%08x (%u)\n", g->field2, g->field2);
 263         debug(ctx, "\tfield3:  0x%08x (%u)\n", g->field3, g->field3);
 264 }
 265
 266 static void debug_dump_devinfo_header(am7xxx_context *ctx, struct am7xxx_devinfo_header *d)
 267 {
 268         if (ctx == NULL || d == NULL)
 269                 return;
 270
 271         debug(ctx, "Info header:\n");
 272         debug(ctx, "\tnative_width:  0x%08x (%u)\n", d->native_width, d->native_width);
 273         debug(ctx, "\tnative_height: 0x%08x (%u)\n", d->native_height, d->native_height);
 274         debug(ctx, "\tunknown0:      0x%08x (%u)\n", d->unknown0, d->unknown0);
 275         debug(ctx, "\tunknown1:      0x%08x (%u)\n", d->unknown1, d->unknown1);
 276 }
 277
 278 static void debug_dump_image_header(am7xxx_context *ctx, struct am7xxx_image_header *i)
 279 {
 280         if (ctx == NULL || i == NULL)
 281                 return;
 282
 283         debug(ctx, "Image header:\n");
 284         debug(ctx, "\tformat:     0x%08x (%u)\n", i->format, i->format);
 285         debug(ctx, "\twidth:      0x%08x (%u)\n", i->width, i->width);
 286         debug(ctx, "\theight:     0x%08x (%u)\n", i->height, i->height);
 287         debug(ctx, "\timage size: 0x%08x (%u)\n", i->image_size, i->image_size);
 288 }
 289
 290 static void debug_dump_power_header(am7xxx_context *ctx, struct am7xxx_power_header *p)
 291 {
 292         if (ctx == NULL || p == NULL)
 293                 return;
 294
 295         debug(ctx, "Power header:\n");
 296         debug(ctx, "\tbit2: 0x%08x (%u)\n", p->bit2, p->bit2);
 297         debug(ctx, "\tbit1: 0x%08x (%u)\n", p->bit1, p->bit1);
 298         debug(ctx, "\tbit0: 0x%08x (%u)\n", p->bit0, p->bit0);
 299 }
 300
 301 static void debug_dump_zoom_header(am7xxx_context *ctx, struct am7xxx_zoom_header *z)
 302 {
 303         if (ctx == NULL || z == NULL)
 304                 return;
 305
 306         debug(ctx, "Zoom header:\n");
 307         debug(ctx, "\tbit1: 0x%08x (%u)\n", z->bit1, z->bit1);
 308         debug(ctx, "\tbit0: 0x%08x (%u)\n", z->bit0, z->bit0);
 309 }
 310
 311 static void debug_dump_header(am7xxx_context *ctx, struct am7xxx_header *h)
 312 {
 313         if (ctx == NULL || h == NULL)
 314                 return;
 315
 316         debug(ctx, "BEGIN\n");
 317         debug(ctx, "packet_type:     0x%08x (%u)\n", h->packet_type, h->packet_type);
 318         debug(ctx, "direction:       0x%02hhx (%hhu) (%s)\n", h->direction, h->direction,
 319               h->direction == AM7XXX_DIRECTION_IN ? "IN" :
 320               h->direction == AM7XXX_DIRECTION_OUT ? "OUT" :
 321               "UNKNOWN");
 322         debug(ctx, "header_data_len: 0x%02hhx (%hhu)\n", h->header_data_len, h->header_data_len);
 323         debug(ctx, "unknown2:        0x%02hhx (%hhu)\n", h->unknown2, h->unknown2);
 324         debug(ctx, "unknown3:        0x%02hhx (%hhu)\n", h->unknown3, h->unknown3);
 325
 326         switch(h->packet_type) {
 327         case AM7XXX_PACKET_TYPE_DEVINFO:
 328                 debug_dump_devinfo_header(ctx, &(h->header_data.devinfo));
 329                 break;
 330
 331         case AM7XXX_PACKET_TYPE_IMAGE:
 332                 debug_dump_image_header(ctx, &(h->header_data.image));
 333                 break;
 334
 335         case AM7XXX_PACKET_TYPE_POWER:
 336                 debug_dump_power_header(ctx, &(h->header_data.power));
 337                 break;
 338
 339         case AM7XXX_PACKET_TYPE_ZOOM:
 340                 debug_dump_zoom_header(ctx, &(h->header_data.zoom));
 341                 break;
 342
 343         default:
 344                 debug(ctx, "Parsing data not supported for this packet type!\n");
 345                 debug_dump_generic_header(ctx, &(h->header_data.data));
 346                 break;
 347         }
 348         debug(ctx, "END\n\n");
 349 }
 350
 351 static inline unsigned int in_80chars(unsigned int i)
 352 {
 353         /* The 3 below is the length of "xx " where xx is the hex string
 354          * representation of a byte */
 355         return ((i + 1) % (80 / 3));
 356 }
 357
 358 static void trace_dump_buffer(am7xxx_context *ctx, const char *message,
 359                               uint8_t *buffer, unsigned int len)
 360 {
 361         unsigned int i;
 362
 363         if (ctx == NULL || buffer == NULL || len == 0)
 364                 return;
 365
 366         trace(ctx, "\n");
 367         if (message)
 368                 trace(ctx, "%s\n", message);
 369
 370         for (i = 0; i < len; i++) {
 371                 trace(ctx, "%02hhX%c", buffer[i], (in_80chars(i) && (i < len - 1)) ? ' ' : '\n');
 372         }
 373         trace(ctx, "\n");
 374 }
 375 #else
 376 static void debug_dump_header(am7xxx_context *ctx, struct am7xxx_header *h)
 377 {
 378         (void)ctx;
 379         (void)h;
 380 }
 381
 382 static void trace_dump_buffer(am7xxx_context *ctx, const char *message,
 383                               uint8_t *buffer, unsigned int len)
 384 {
 385         (void)ctx;
 386         (void)message;
 387         (void)buffer;
 388         (void)len;
 389 }
 390 #endif /* DEBUG */
 391
 392 static int read_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 393 {
 394         int ret;
 395         int transferred;
 396
 397         transferred = 0;
 398         ret = libusb_bulk_transfer(dev->usb_device, 0x81, buffer, len, &transferred, 0);
 399         if (ret != 0 || (unsigned int)transferred != len) {
 400                 error(dev->ctx, "%s. Transferred: %d (expected %u)\n",
 401                       libusb_error_name(ret), transferred, len);
 402                 return ret;
 403         }
 404
 405         trace_dump_buffer(dev->ctx, "<-- received", buffer, len);
 406
 407         return 0;
 408 }
 409
 410 static int send_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 411 {
 412         int ret;
 413         int transferred;
 414
 415         trace_dump_buffer(dev->ctx, "sending -->", buffer, len);
 416
 417         transferred = 0;
 418         ret = libusb_bulk_transfer(dev->usb_device, 0x1, buffer, len, &transferred, 0);
 419         if (ret != 0 || (unsigned int)transferred != len) {
 420                 error(dev->ctx, "%s. Transferred: %d (expected %u)\n",
 421                       libusb_error_name(ret), transferred, len);
 422                 return ret;
 423         }
 424
 425         return 0;
 426 }
 427
 428 static void LIBUSB_CALL send_data_async_complete_cb(struct libusb_transfer *transfer)
 429 {
 430         am7xxx_device *dev = (am7xxx_device *)(transfer->user_data);
 431         int *completed = &(dev->transfer_completed);
 432         int transferred = transfer->actual_length;
 433         int ret;
 434
 435         if (transferred != transfer->length) {
 436                 error(dev->ctx, "transferred: %d (expected %u)\n",
 437                       transferred, transfer->length);
 438         }
 439
 440         switch (transfer->status) {
 441         case LIBUSB_TRANSFER_COMPLETED:
 442                 ret = 0;
 443                 break;
 444         case LIBUSB_TRANSFER_TIMED_OUT:
 445                 ret = LIBUSB_ERROR_TIMEOUT;
 446                 break;
 447         case LIBUSB_TRANSFER_STALL:
 448                 ret = LIBUSB_ERROR_PIPE;
 449                 break;
 450         case LIBUSB_TRANSFER_OVERFLOW:
 451                 ret = LIBUSB_ERROR_OVERFLOW;
 452                 break;
 453         case LIBUSB_TRANSFER_NO_DEVICE:
 454                 ret = LIBUSB_ERROR_NO_DEVICE;
 455                 break;
 456         case LIBUSB_TRANSFER_ERROR:
 457         case LIBUSB_TRANSFER_CANCELLED:
 458                 ret = LIBUSB_ERROR_IO;
 459                 break;
 460         default:
 461                 error(dev->ctx, "unrecognised status code %d", transfer->status);
 462                 ret = LIBUSB_ERROR_OTHER;
 463         }
 464
 465         if (ret < 0)
 466                 error(dev->ctx, "libusb transfer failed: %s",
 467                       libusb_error_name(ret));
 468
 469         libusb_free_transfer(transfer);
 470         transfer = NULL;
 471
 472         *completed = 1;
 473 }
 474
 475 static inline void wait_for_trasfer_completed(am7xxx_device *dev)
 476 {
 477         while (!dev->transfer_completed) {
 478                 int ret = libusb_handle_events_completed(dev->ctx->usb_context,
 479                                                          &(dev->transfer_completed));
 480                 if (ret < 0) {
 481                         if (ret == LIBUSB_ERROR_INTERRUPTED)
 482                                 continue;
 483                         error(dev->ctx, "libusb_handle_events failed: %s, cancelling transfer and retrying",
 484                               libusb_error_name(ret));
 485                         libusb_cancel_transfer(dev->transfer);
 486                         continue;
 487                 }
 488         }
 489 }
 490
 491 static int send_data_async(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 492 {
 493         int ret;
 494         uint8_t *transfer_buffer;
 495
 496         dev->transfer = libusb_alloc_transfer(0);
 497         if (dev->transfer == NULL) {
 498                 error(dev->ctx, "cannot allocate transfer (%s)\n",
 499                       strerror(errno));
 500                 return -ENOMEM;
 501         }
 502
 503         /* Make a copy of the buffer so the caller can safely reuse it just
 504          * after libusb_submit_transfer() has returned. This technique
 505          * requires more dynamic allocations compared to a proper
 506          * double-buffering approach but it takes a lot less code. */
 507         transfer_buffer = malloc(len);
 508         if (transfer_buffer == NULL) {
 509                 error(dev->ctx, "cannot allocate transfer buffer (%s)\n",
 510                       strerror(errno));
 511                 ret = -ENOMEM;
 512                 goto err;
 513         }
 514         memcpy(transfer_buffer, buffer, len);
 515
 516         dev->transfer->flags |= LIBUSB_TRANSFER_FREE_BUFFER;
 517         libusb_fill_bulk_transfer(dev->transfer, dev->usb_device, 0x1,
 518                                   transfer_buffer, len,
 519                                   send_data_async_complete_cb, dev, 0);
 520
 521         /* wait for the previous transfer to complete */
 522         wait_for_trasfer_completed(dev);
 523
 524         trace_dump_buffer(dev->ctx, "sending -->", buffer, len);
 525
 526         dev->transfer_completed = 0;
 527         ret = libusb_submit_transfer(dev->transfer);
 528         if (ret < 0)
 529                 goto err;
 530
 531         return 0;
 532
 533 err:
 534         libusb_free_transfer(dev->transfer);
 535         dev->transfer = NULL;
 536         return ret;
 537 }
 538
 539 static void serialize_header(struct am7xxx_header *h, uint8_t *buffer)
 540 {
 541         uint8_t **buffer_iterator = &buffer;
 542
 543         put_le32(h->packet_type, buffer_iterator);
 544         put_8(h->direction, buffer_iterator);
 545         put_8(h->header_data_len, buffer_iterator);
 546         put_8(h->unknown2, buffer_iterator);
 547         put_8(h->unknown3, buffer_iterator);
 548         put_le32(h->header_data.data.field0, buffer_iterator);
 549         put_le32(h->header_data.data.field1, buffer_iterator);
 550         put_le32(h->header_data.data.field2, buffer_iterator);
 551         put_le32(h->header_data.data.field3, buffer_iterator);
 552 }
 553
 554 static void unserialize_header(uint8_t *buffer, struct am7xxx_header *h)
 555 {
 556         uint8_t **buffer_iterator = &buffer;
 557
 558         h->packet_type = get_le32(buffer_iterator);
 559         h->direction = get_8(buffer_iterator);
 560         h->header_data_len = get_8(buffer_iterator);
 561         h->unknown2 = get_8(buffer_iterator);
 562         h->unknown3 = get_8(buffer_iterator);
 563         h->header_data.data.field0 = get_le32(buffer_iterator);
 564         h->header_data.data.field1 = get_le32(buffer_iterator);
 565         h->header_data.data.field2 = get_le32(buffer_iterator);
 566         h->header_data.data.field3 = get_le32(buffer_iterator);
 567 }
 568
 569 static int read_header(am7xxx_device *dev, struct am7xxx_header *h)
 570 {
 571         int ret;
 572
 573         ret = read_data(dev, dev->buffer, AM7XXX_HEADER_WIRE_SIZE);
 574         if (ret < 0)
 575                 goto out;
 576
 577         unserialize_header(dev->buffer, h);
 578
 579         if (h->direction == AM7XXX_DIRECTION_IN) {
 580                 ret = 0;
 581         } else {
 582                 error(dev->ctx,
 583                       "Expected an AM7XXX_DIRECTION_IN packet, got one with direction = %d. Weird!\n",
 584                       h->direction);
 585                 ret = -EINVAL;
 586         }
 587
 588         debug_dump_header(dev->ctx, h);
 589
 590 out:
 591         return ret;
 592 }
 593
 594 static int send_header(am7xxx_device *dev, struct am7xxx_header *h)
 595 {
 596         int ret;
 597
 598         debug_dump_header(dev->ctx, h);
 599
 600         /* For symmetry with read_header() we should check here for
 601          * h->direction == AM7XXX_DIRECTION_OUT but we just ensure that in all
 602          * the callers and save some cycles here.
 603          */
 604
 605         serialize_header(h, dev->buffer);
 606
 607         ret = send_data(dev, dev->buffer, AM7XXX_HEADER_WIRE_SIZE);
 608         if (ret < 0)
 609                 error(dev->ctx, "failed to send data\n");
 610
 611         return ret;
 612 }
 613
 614 static int send_command(am7xxx_device *dev, am7xxx_packet_type type)
 615 {
 616         struct am7xxx_header h = {
 617                 .packet_type     = type,
 618                 .direction       = AM7XXX_DIRECTION_OUT,
 619                 .header_data_len = 0x00,
 620                 .unknown2        = 0x3e,
 621                 .unknown3        = 0x10,
 622                 .header_data = {
 623                         .data = {
 624                                 .field0 = 0,
 625                                 .field1 = 0,
 626                                 .field2 = 0,
 627                                 .field3 = 0,
 628                         },
 629                 },
 630         };
 631
 632         return send_header(dev, &h);
 633 }
 634
 635
 636 /* When level == AM7XXX_LOG_FATAL do not check the log_level from the context
 637  * and print the message unconditionally, this makes it possible to print
 638  * fatal messages even early on initialization, before the context has been
 639  * set up */
 640 static void log_message(am7xxx_context *ctx,
 641                         int level,
 642                         const char *function_name,
 643                         int line,
 644                         const char *fmt,
 645                         ...)
 646 {
 647         va_list ap;
 648
 649         if (level == AM7XXX_LOG_FATAL || (ctx && level <= ctx->log_level)) {
 650                 if (function_name) {
 651                         fprintf(stderr, "%s", function_name);
 652                         if (line)
 653                                 fprintf(stderr, "[%d]", line);
 654                         fprintf(stderr, ": ");
 655                 }
 656
 657                 va_start(ap, fmt);
 658                 vfprintf(stderr, fmt, ap);
 659                 va_end(ap);
 660         }
 661
 662         return;
 663 }
 664
 665 static am7xxx_device *add_new_device(am7xxx_context *ctx,
 666                                      const struct am7xxx_usb_device_descriptor *desc)
 667 {
 668         am7xxx_device **devices_list;
 669         am7xxx_device *new_device;
 670
 671         if (ctx == NULL) {
 672                 fatal("context must not be NULL!\n");
 673                 return NULL;
 674         }
 675
 676         new_device = malloc(sizeof(*new_device));
 677         if (new_device == NULL) {
 678                 debug(ctx, "cannot allocate a new device (%s)\n", strerror(errno));
 679                 return NULL;
 680         }
 681         memset(new_device, 0, sizeof(*new_device));
 682
 683         new_device->ctx = ctx;
 684         new_device->desc = desc;
 685         new_device->transfer_completed = 1;
 686
 687         devices_list = &(ctx->devices_list);
 688
 689         if (*devices_list == NULL) {
 690                 *devices_list = new_device;
 691         } else {
 692                 am7xxx_device *prev = *devices_list;
 693                 while (prev->next)
 694                         prev = prev->next;
 695                 prev->next = new_device;
 696         }
 697         return new_device;
 698 }
 699
 700 static am7xxx_device *find_device(am7xxx_context *ctx,
 701                                   unsigned int device_index)
 702 {
 703         unsigned int i = 0;
 704         am7xxx_device *current;
 705
 706         if (ctx == NULL) {
 707                 fatal("context must not be NULL!\n");
 708                 return NULL;
 709         }
 710
 711         current = ctx->devices_list;
 712         while (current && i++ < device_index)
 713                 current = current->next;
 714
 715         return current;
 716 }
 717
 718 static int open_device(am7xxx_context *ctx,
 719                        unsigned int device_index,
 720                        libusb_device *usb_dev,
 721                        am7xxx_device **dev)
 722 {
 723         int ret;
 724         int current_configuration;
 725
 726         *dev = find_device(ctx, device_index);
 727         if (*dev == NULL) {
 728                 ret = -ENODEV;
 729                 goto out;
 730         }
 731
 732         /* the usb device has already been opened */
 733         if ((*dev)->usb_device) {
 734                 ret = 1;
 735                 goto out;
 736         }
 737
 738         ret = libusb_open(usb_dev, &((*dev)->usb_device));
 739         if (ret < 0) {
 740                 debug(ctx, "libusb_open failed: %s\n", libusb_error_name(ret));
 741                 goto out;
 742         }
 743
 744         /* XXX, the device is now open, if any of the calls below fail we need
 745          * to close it again before bailing out.
 746          */
 747
 748         current_configuration = -1;
 749         ret = libusb_get_configuration((*dev)->usb_device,
 750                                        &current_configuration);
 751         if (ret < 0) {
 752                 debug(ctx, "libusb_get_configuration failed: %s\n",
 753                       libusb_error_name(ret));
 754                 goto out_libusb_close;
 755         }
 756
 757         if (current_configuration != (*dev)->desc->configuration) {
 758                 /*
 759                  * In principle, before setting a new configuration, kernel
 760                  * drivers should be detached from _all_ interfaces; for
 761                  * example calling something like the following "invented"
 762                  * function _before_ setting the new configuration:
 763                  *
 764                  *   libusb_detach_all_kernel_drivers((*dev)->usb_device);
 765                  *
 766                  * However, in practice, this is not necessary for most
 767                  * devices as they have only one configuration.
 768                  *
 769                  * When a device only has one configuration:
 770                  *
 771                  *   - if there was a kernel driver bound to the device, it
 772                  *     had already set the configuration and the call below
 773                  *     will be skipped;
 774                  *
 775                  *   - if no kernel driver was bound to the device, the call
 776                  *     below will suceed.
 777                  */
 778                 ret = libusb_set_configuration((*dev)->usb_device,
 779                                                (*dev)->desc->configuration);
 780                 if (ret < 0) {
 781                         debug(ctx, "libusb_set_configuration failed: %s\n",
 782                               libusb_error_name(ret));
 783                         debug(ctx, "Cannot set configuration %hhu\n",
 784                               (*dev)->desc->configuration);
 785                         goto out_libusb_close;
 786                 }
 787         }
 788
 789         libusb_set_auto_detach_kernel_driver((*dev)->usb_device, 1);
 790
 791         ret = libusb_claim_interface((*dev)->usb_device,
 792                                      (*dev)->desc->interface_number);
 793         if (ret < 0) {
 794                 debug(ctx, "libusb_claim_interface failed: %s\n",
 795                       libusb_error_name(ret));
 796                 debug(ctx, "Cannot claim interface %hhu\n",
 797                       (*dev)->desc->interface_number);
 798                 goto out_libusb_close;
 799         }
 800
 801         /* Checking that the configuration has not changed, as suggested in
 802          * http://libusb.sourceforge.net/api-1.0/caveats.html
 803          */
 804         current_configuration = -1;
 805         ret = libusb_get_configuration((*dev)->usb_device,
 806                                        &current_configuration);
 807         if (ret < 0) {
 808                 debug(ctx, "libusb_get_configuration after claim failed: %s\n",
 809                       libusb_error_name(ret));
 810                 goto out_libusb_release_interface;
 811         }
 812
 813         if (current_configuration != (*dev)->desc->configuration) {
 814                 debug(ctx, "libusb configuration changed (expected: %hhu, current: %d)\n",
 815                       (*dev)->desc->configuration, current_configuration);
 816                 ret = -EINVAL;
 817                 goto out_libusb_release_interface;
 818         }
 819 out:
 820         return ret;
 821
 822 out_libusb_release_interface:
 823         libusb_release_interface((*dev)->usb_device,
 824                                  (*dev)->desc->interface_number);
 825 out_libusb_close:
 826         libusb_close((*dev)->usb_device);
 827         (*dev)->usb_device = NULL;
 828         return ret;
 829 }
 830
 831 typedef enum {
 832         SCAN_OP_BUILD_DEVLIST,
 833         SCAN_OP_OPEN_DEVICE,
 834 } scan_op;
 835
 836 /**
 837  * This is where the central logic of multi-device support is.
 838  *
 839  * When 'op' == SCAN_OP_BUILD_DEVLIST the parameters 'open_device_index' and
 840  * 'dev' are ignored; the function returns 0 on success or a negative value
 841  * on error.
 842  *
 843  * When 'op' == SCAN_OP_OPEN_DEVICE the function opens the supported USB
 844  * device with index 'open_device_index' and returns the correspondent
 845  * am7xxx_device in the 'dev' parameter; the function returns the value from
 846  * open_device(), which is 0 on success, 1 if the device was already open or
 847  * a negative value on error.
 848  *
 849  * NOTES:
 850  * if scan_devices() fails when called with 'op' == SCAN_OP_BUILD_DEVLIST,
 851  * the caller might want to call am7xxx_shutdown() in order to remove
 852  * devices possibly added before the failure.
 853  */
 854 static int scan_devices(am7xxx_context *ctx, scan_op op,
 855                         unsigned int open_device_index, am7xxx_device **dev)
 856 {
 857         ssize_t num_devices;
 858         libusb_device **list;
 859         unsigned int current_index;
 860         int i;
 861         int ret;
 862
 863         if (ctx == NULL) {
 864                 fatal("context must not be NULL!\n");
 865                 return -EINVAL;
 866         }
 867         if (op == SCAN_OP_BUILD_DEVLIST && ctx->devices_list != NULL) {
 868                 error(ctx, "device scan done already? Abort!\n");
 869                 return -EINVAL;
 870         }
 871
 872         num_devices = libusb_get_device_list(ctx->usb_context, &list);
 873         if (num_devices < 0) {
 874                 ret = -ENODEV;
 875                 goto out;
 876         }
 877
 878         current_index = 0;
 879         for (i = 0; i < num_devices; i++) {
 880                 struct libusb_device_descriptor desc;
 881                 unsigned int j;
 882
 883                 ret = libusb_get_device_descriptor(list[i], &desc);
 884                 if (ret < 0)
 885                         continue;
 886
 887                 for (j = 0; j < ARRAY_SIZE(supported_devices); j++) {
 888                         if (desc.idVendor == supported_devices[j].vendor_id &&
 889                             desc.idProduct == supported_devices[j].product_id) {
 890
 891                                 if (op == SCAN_OP_BUILD_DEVLIST) {
 892                                         am7xxx_device *new_device;
 893                                         info(ctx, "am7xxx device found, index: %d, name: %s\n",
 894                                              current_index,
 895                                              supported_devices[j].name);
 896                                         new_device = add_new_device(ctx, &supported_devices[j]);
 897                                         if (new_device == NULL) {
 898                                                 /* XXX, the caller may want
 899                                                  * to call am7xxx_shutdown() if
 900                                                  * we fail here, as we may have
 901                                                  * added some devices already
 902                                                  */
 903                                                 debug(ctx, "Cannot create a new device\n");
 904                                                 ret = -ENODEV;
 905                                                 goto out;
 906                                         }
 907                                 } else if (op == SCAN_OP_OPEN_DEVICE &&
 908                                            current_index == open_device_index) {
 909
 910                                         ret = open_device(ctx,
 911                                                           open_device_index,
 912                                                           list[i],
 913                                                           dev);
 914                                         if (ret < 0)
 915                                                 debug(ctx, "open_device failed\n");
 916
 917                                         /* exit the loop unconditionally after
 918                                          * attempting to open the device
 919                                          * requested by the user */
 920                                         goto out;
 921                                 }
 922                                 current_index++;
 923                         }
 924                 }
 925         }
 926
 927         /* if we made it up to here when op == SCAN_OP_OPEN_DEVICE,
 928          * no devices to open had been found. */
 929         if (op == SCAN_OP_OPEN_DEVICE) {
 930                 error(ctx, "Cannot find any device to open\n");
 931                 ret = -ENODEV;
 932                 goto out;
 933         }
 934
 935         /* everything went fine when building the device list */
 936         ret = 0;
 937 out:
 938         libusb_free_device_list(list, 1);
 939         return ret;
 940 }
 941
 942 /* Device specific operations */
 943
 944 static int default_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power)
 945 {
 946         int ret;
 947         struct am7xxx_header h = {
 948                 .packet_type     = AM7XXX_PACKET_TYPE_POWER,
 949                 .direction       = AM7XXX_DIRECTION_OUT,
 950                 .header_data_len = sizeof(struct am7xxx_power_header),
 951                 .unknown2        = 0x3e,
 952                 .unknown3        = 0x10,
 953         };
 954
 955         switch(power) {
 956         case AM7XXX_POWER_OFF:
 957                 h.header_data.power.bit2 = 0;
 958                 h.header_data.power.bit1 = 0;
 959                 h.header_data.power.bit0 = 0;
 960                 break;
 961
 962         case AM7XXX_POWER_LOW:
 963                 h.header_data.power.bit2 = 0;
 964                 h.header_data.power.bit1 = 0;
 965                 h.header_data.power.bit0 = 1;
 966                 break;
 967
 968         case AM7XXX_POWER_MIDDLE:
 969                 h.header_data.power.bit2 = 0;
 970                 h.header_data.power.bit1 = 1;
 971                 h.header_data.power.bit0 = 0;
 972                 break;
 973
 974         case AM7XXX_POWER_HIGH:
 975                 h.header_data.power.bit2 = 0;
 976                 h.header_data.power.bit1 = 1;
 977                 h.header_data.power.bit0 = 1;
 978                 break;
 979
 980         case AM7XXX_POWER_TURBO:
 981                 h.header_data.power.bit2 = 1;
 982                 h.header_data.power.bit1 = 0;
 983                 h.header_data.power.bit0 = 0;
 984                 break;
 985
 986         default:
 987                 error(dev->ctx, "Unsupported power mode.\n");
 988                 return -EINVAL;
 989         };
 990
 991         ret = send_header(dev, &h);
 992         if (ret < 0)
 993                 return ret;
 994
 995         return 0;
 996 }
 997
 998 static int picopix_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power)
 999 {
1000         switch(power) {
1001         case AM7XXX_POWER_LOW:
1002                 return send_command(dev, AM7XXX_PACKET_TYPE_PICOPIX_POWER_LOW);
1003
1004         case AM7XXX_POWER_MIDDLE:
1005                 return send_command(dev, AM7XXX_PACKET_TYPE_PICOPIX_POWER_MEDIUM);
1006
1007         case AM7XXX_POWER_HIGH:
1008                 return send_command(dev, AM7XXX_PACKET_TYPE_PICOPIX_POWER_HIGH);
1009
1010         case AM7XXX_POWER_OFF:
1011         case AM7XXX_POWER_TURBO:
1012         default:
1013                 error(dev->ctx, "Unsupported power mode.\n");
1014                 return -EINVAL;
1015         };
1016 }
1017
1018 static int default_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom)
1019 {
1020         int ret;
1021         struct am7xxx_header h = {
1022                 .packet_type     = AM7XXX_PACKET_TYPE_ZOOM,
1023                 .direction       = AM7XXX_DIRECTION_OUT,
1024                 .header_data_len = sizeof(struct am7xxx_zoom_header),
1025                 .unknown2        = 0x3e,
1026                 .unknown3        = 0x10,
1027         };
1028
1029         switch(zoom) {
1030         case AM7XXX_ZOOM_ORIGINAL:
1031                 h.header_data.zoom.bit1 = 0;
1032                 h.header_data.zoom.bit0 = 0;
1033                 break;
1034
1035         case AM7XXX_ZOOM_H:
1036                 h.header_data.zoom.bit1 = 0;
1037                 h.header_data.zoom.bit0 = 1;
1038                 break;
1039
1040         case AM7XXX_ZOOM_H_V:
1041                 h.header_data.zoom.bit1 = 1;
1042                 h.header_data.zoom.bit0 = 0;
1043                 break;
1044
1045         case AM7XXX_ZOOM_TEST:
1046                 h.header_data.zoom.bit1 = 1;
1047                 h.header_data.zoom.bit0 = 1;
1048                 break;
1049
1050         case AM7XXX_ZOOM_TELE:
1051         default:
1052                 error(dev->ctx, "Unsupported zoom mode.\n");
1053                 return -EINVAL;
1054         };
1055
1056         ret = send_header(dev, &h);
1057         if (ret < 0)
1058                 return ret;
1059
1060         return 0;
1061 }
1062
1063 static int picopix_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom)
1064 {
1065         int ret;
1066         am7xxx_packet_type packet_type;
1067
1068         switch(zoom) {
1069         case AM7XXX_ZOOM_ORIGINAL:
1070                 packet_type = AM7XXX_PACKET_TYPE_PICOPIX_DISABLE_TI;
1071                 break;
1072
1073         case AM7XXX_ZOOM_TELE:
1074                 packet_type = AM7XXX_PACKET_TYPE_PICOPIX_ENABLE_TI;
1075                 break;
1076
1077         case AM7XXX_ZOOM_H:
1078         case AM7XXX_ZOOM_H_V:
1079         case AM7XXX_ZOOM_TEST:
1080         default:
1081                 error(dev->ctx, "Unsupported zoom mode.\n");
1082                 return -EINVAL;
1083         };
1084
1085         ret = send_command(dev, packet_type);
1086         if (ret < 0)
1087                 return ret;
1088
1089         /* The Windows drivers wait for 100ms and send the same command again,
1090          * probably to overcome a firmware deficiency */
1091         ret = msleep(100);
1092         if (ret < 0)
1093                 return ret;
1094
1095         return send_command(dev, packet_type);
1096 }
1097
1098 /* Public API */
1099
1100 AM7XXX_PUBLIC int am7xxx_init(am7xxx_context **ctx)
1101 {
1102         int ret;
1103
1104         *ctx = malloc(sizeof(**ctx));
1105         if (*ctx == NULL) {
1106                 fatal("cannot allocate the context (%s)\n", strerror(errno));
1107                 return -ENOMEM;
1108         }
1109         memset(*ctx, 0, sizeof(**ctx));
1110
1111         /* Set the highest log level during initialization */
1112         (*ctx)->log_level = AM7XXX_LOG_TRACE;
1113
1114         ret = libusb_init(&((*ctx)->usb_context));
1115         if (ret < 0) {
1116                 error(*ctx, "libusb_init failed: %s\n", libusb_error_name(ret));
1117                 goto out_free_context;
1118         }
1119
1120         libusb_set_debug((*ctx)->usb_context, LIBUSB_LOG_LEVEL_INFO);
1121
1122         ret = scan_devices(*ctx, SCAN_OP_BUILD_DEVLIST , 0, NULL);
1123         if (ret < 0) {
1124                 error(*ctx, "scan_devices() failed\n");
1125                 am7xxx_shutdown(*ctx);
1126                 goto out;
1127         }
1128
1129         /* Set a quieter log level as default for normal operation */
1130         (*ctx)->log_level = AM7XXX_LOG_ERROR;
1131         return 0;
1132
1133 out_free_context:
1134         free(*ctx);
1135         *ctx = NULL;
1136 out:
1137         return ret;
1138 }
1139
1140 AM7XXX_PUBLIC void am7xxx_shutdown(am7xxx_context *ctx)
1141 {
1142         am7xxx_device *current;
1143
1144         if (ctx == NULL) {
1145                 fatal("context must not be NULL!\n");
1146                 return;
1147         }
1148
1149         current = ctx->devices_list;
1150         while (current) {
1151                 am7xxx_device *next = current->next;
1152                 am7xxx_close_device(current);
1153                 free(current->device_info);
1154                 free(current);
1155                 current = next;
1156         }
1157
1158         libusb_exit(ctx->usb_context);
1159         free(ctx);
1160         ctx = NULL;
1161 }
1162
1163 AM7XXX_PUBLIC void am7xxx_set_log_level(am7xxx_context *ctx, am7xxx_log_level log_level)
1164 {
1165         ctx->log_level = log_level;
1166 }
1167
1168 AM7XXX_PUBLIC int am7xxx_open_device(am7xxx_context *ctx, am7xxx_device **dev,
1169                        unsigned int device_index)
1170 {
1171         int ret;
1172
1173         if (ctx == NULL) {
1174                 fatal("context must not be NULL!\n");
1175                 return -EINVAL;
1176         }
1177
1178         ret = scan_devices(ctx, SCAN_OP_OPEN_DEVICE, device_index, dev);
1179         if (ret < 0) {
1180                 errno = ENODEV;
1181                 goto out;
1182         } else if (ret > 0) {
1183                 warning(ctx, "device %d already open\n", device_index);
1184                 errno = EBUSY;
1185                 ret = -EBUSY;
1186                 goto out;
1187         }
1188
1189         /* Philips/Sagemcom PicoPix projectors require that the DEVINFO packet
1190          * is the first one to be sent to the device in order for it to
1191          * successfully return the correct device information.
1192          *
1193          * NOTE: am7xxx_get_device_info() will fetch the actual device info
1194          * from the device only the very first time it's called for a given
1195          * device, otherwise, it'll return a cached version of the device info
1196          * (from a previous call to am7xxx_open_device(), for instance).
1197          */
1198         ret = am7xxx_get_device_info(*dev, NULL);
1199         if (ret < 0)
1200                 error(ctx, "cannot get device info\n");
1201
1202 out:
1203         return ret;
1204 }
1205
1206 AM7XXX_PUBLIC int am7xxx_close_device(am7xxx_device *dev)
1207 {
1208         if (dev == NULL) {
1209                 fatal("dev must not be NULL!\n");
1210                 return -EINVAL;
1211         }
1212         if (dev->usb_device) {
1213                 wait_for_trasfer_completed(dev);
1214                 libusb_release_interface(dev->usb_device, dev->desc->interface_number);
1215                 libusb_close(dev->usb_device);
1216                 dev->usb_device = NULL;
1217         }
1218         return 0;
1219 }
1220
1221 AM7XXX_PUBLIC int am7xxx_get_device_info(am7xxx_device *dev,
1222                            am7xxx_device_info *device_info)
1223 {
1224         int ret;
1225         struct am7xxx_header h;
1226
1227         /* if there is a cached copy of the device info, just return that */
1228         if (dev->device_info)
1229                 goto return_value;
1230
1231         ret = send_command(dev, AM7XXX_PACKET_TYPE_DEVINFO);
1232         if (ret < 0)
1233                 return ret;
1234
1235         memset(&h, 0, sizeof(h));
1236         ret = read_header(dev, &h);
1237         if (ret < 0)
1238                 return ret;
1239
1240         if (h.packet_type != AM7XXX_PACKET_TYPE_DEVINFO) {
1241                 error(dev->ctx, "expected packet type: %d, got %d instead!\n",
1242                       AM7XXX_PACKET_TYPE_DEVINFO, h.packet_type);
1243                 errno = EINVAL;
1244                 return -EINVAL;
1245         }
1246
1247         dev->device_info = malloc(sizeof(*dev->device_info));
1248         if (dev->device_info == NULL) {
1249                 error(dev->ctx, "cannot allocate a device info (%s)\n",
1250                        strerror(errno));
1251                 return -ENOMEM;
1252         }
1253         memset(dev->device_info, 0, sizeof(*dev->device_info));
1254
1255         dev->device_info->native_width = h.header_data.devinfo.native_width;
1256         dev->device_info->native_height = h.header_data.devinfo.native_height;
1257 #if 0
1258         /* No reason to expose these in the public API until we know what they mean */
1259         dev->device_info->unknown0 = h.header_data.devinfo.unknown0;
1260         dev->device_info->unknown1 = h.header_data.devinfo.unknown1;
1261 #endif
1262
1263 return_value:
1264         if (device_info)
1265                 memcpy(device_info, dev->device_info, sizeof(*device_info));
1266         return 0;
1267 }
1268
1269 AM7XXX_PUBLIC int am7xxx_calc_scaled_image_dimensions(am7xxx_device *dev,
1270                                         unsigned int upscale,
1271                                         unsigned int original_width,
1272                                         unsigned int original_height,
1273                                         unsigned int *scaled_width,
1274                                         unsigned int *scaled_height)
1275 {
1276         am7xxx_device_info device_info;
1277         float width_ratio;
1278         float height_ratio;
1279         int ret;
1280
1281         ret = am7xxx_get_device_info(dev, &device_info);
1282         if (ret < 0) {
1283                 error(dev->ctx, "cannot get device info\n");
1284                 return ret;
1285         }
1286
1287         /*
1288          * Check if we need to rescale; if the input image fits the native
1289          * dimensions there is no need to, unless we want to upscale.
1290          */
1291         if (!upscale &&
1292             original_width <= device_info.native_width &&
1293             original_height <= device_info.native_height ) {
1294                 debug(dev->ctx, "CASE 0, no rescaling, the original image fits already\n");
1295                 *scaled_width = original_width;
1296                 *scaled_height = original_height;
1297                 return 0;
1298         }
1299
1300         /* Input dimensions relative to the device native dimensions */
1301         width_ratio =  (float)original_width / device_info.native_width;
1302         height_ratio = (float)original_height / device_info.native_height;
1303
1304         if (width_ratio > height_ratio) {
1305                 /*
1306                  * The input is proportionally "wider" than the device viewport
1307                  * so its height needs to be adjusted
1308                  */
1309                 debug(dev->ctx, "CASE 1, original image wider, adjust the scaled height\n");
1310                 *scaled_width = device_info.native_width;
1311                 *scaled_height = (unsigned int)lroundf(original_height / width_ratio);
1312         } else if (width_ratio < height_ratio) {
1313                 /*
1314                  * The input is proportionally "taller" than the device viewport
1315                  * so its width needs to be adjusted
1316                  */
1317                 debug(dev->ctx, "CASE 2 original image taller, adjust the scaled width\n");
1318                 *scaled_width = (unsigned int)lroundf(original_width / height_ratio);
1319                 *scaled_height = device_info.native_height;
1320         } else {
1321                 debug(dev->ctx, "CASE 3, just rescale, same aspect ratio already\n");
1322                 *scaled_width = device_info.native_width;
1323                 *scaled_height = device_info.native_height;
1324         }
1325         debug(dev->ctx, "scaled dimensions: %dx%d\n", *scaled_width, *scaled_height);
1326
1327         return 0;
1328 }
1329
1330 AM7XXX_PUBLIC int am7xxx_send_image(am7xxx_device *dev,
1331                       am7xxx_image_format format,
1332                       unsigned int width,
1333                       unsigned int height,
1334                       uint8_t *image,
1335                       unsigned int image_size)
1336 {
1337         int ret;
1338         struct am7xxx_header h = {
1339                 .packet_type     = AM7XXX_PACKET_TYPE_IMAGE,
1340                 .direction       = AM7XXX_DIRECTION_OUT,
1341                 .header_data_len = sizeof(struct am7xxx_image_header),
1342                 .unknown2        = 0x3e,
1343                 .unknown3        = 0x10,
1344                 .header_data = {
1345                         .image = {
1346                                 .format     = format,
1347                                 .width      = width,
1348                                 .height     = height,
1349                                 .image_size = image_size,
1350                         },
1351                 },
1352         };
1353
1354         ret = send_header(dev, &h);
1355         if (ret < 0)
1356                 return ret;
1357
1358         if (image == NULL || image_size == 0) {
1359                 warning(dev->ctx, "Not sending any data, check the 'image' or 'image_size' parameters\n");
1360                 return 0;
1361         }
1362
1363         return send_data(dev, image, image_size);
1364 }
1365
1366 AM7XXX_PUBLIC int am7xxx_send_image_async(am7xxx_device *dev,
1367                                           am7xxx_image_format format,
1368                                           unsigned int width,
1369                                           unsigned int height,
1370                                           uint8_t *image,
1371                                           unsigned int image_size)
1372 {
1373         int ret;
1374         struct am7xxx_header h = {
1375                 .packet_type     = AM7XXX_PACKET_TYPE_IMAGE,
1376                 .direction       = AM7XXX_DIRECTION_OUT,
1377                 .header_data_len = sizeof(struct am7xxx_image_header),
1378                 .unknown2        = 0x3e,
1379                 .unknown3        = 0x10,
1380                 .header_data = {
1381                         .image = {
1382                                 .format     = format,
1383                                 .width      = width,
1384                                 .height     = height,
1385                                 .image_size = image_size,
1386                         },
1387                 },
1388         };
1389
1390         ret = send_header(dev, &h);
1391         if (ret < 0)
1392                 return ret;
1393
1394         if (image == NULL || image_size == 0) {
1395                 warning(dev->ctx, "Not sending any data, check the 'image' or 'image_size' parameters\n");
1396                 return 0;
1397         }
1398
1399         return send_data_async(dev, image, image_size);
1400 }
1401
1402 AM7XXX_PUBLIC int am7xxx_set_power_mode(am7xxx_device *dev, am7xxx_power_mode power)
1403 {
1404         if (dev->desc->ops.set_power_mode == NULL) {
1405                 warning(dev->ctx,
1406                         "setting power mode is unsupported on this device\n");
1407                 return 0;
1408         }
1409
1410         return dev->desc->ops.set_power_mode(dev, power);
1411 }
1412
1413 AM7XXX_PUBLIC int am7xxx_set_zoom_mode(am7xxx_device *dev, am7xxx_zoom_mode zoom)
1414 {
1415         if (dev->desc->ops.set_zoom_mode == NULL) {
1416                 warning(dev->ctx,
1417                         "setting zoom mode is unsupported on this device\n");
1418                 return 0;
1419         }
1420
1421         return dev->desc->ops.set_zoom_mode(dev, zoom);
1422 }