+int am7xxx_init(am7xxx_context **ctx)
+{
+ int ret = 0;
+
+ *ctx = malloc(sizeof(**ctx));
+ if (*ctx == NULL) {
+ perror("malloc");
+ ret = -ENOMEM;
+ goto out;
+ }
+ memset(*ctx, 0, sizeof(**ctx));
+
+ ret = libusb_init(&((*ctx)->usb_context));
+ if (ret < 0)
+ goto out_free_context;
+
+ libusb_set_debug((*ctx)->usb_context, 3);
+
+ ret = scan_devices(*ctx, SCAN_OP_BUILD_DEVLIST , 0, NULL);
+ if (ret < 0) {
+ fprintf(stderr, "%s: scan_devices failed\n", __func__);
+ am7xxx_shutdown(*ctx);
+ goto out;
+ }
+
+ return 0;
+
+out_free_context:
+ free(*ctx);
+ *ctx = NULL;
+out:
+ return ret;
+}
+
+void am7xxx_shutdown(am7xxx_context *ctx)
+{
+ am7xxx_device *current;
+
+ if (ctx == NULL) {
+ fprintf(stderr, "%s: context must not be NULL!\n", __func__);
+ return;
+ }
+
+ current = ctx->devices_list;
+ while (current) {
+ am7xxx_device *next = current->next;
+ am7xxx_close_device(current);
+ free(current);
+ current = next;
+ }
+
+ libusb_exit(ctx->usb_context);
+ free(ctx);
+ ctx = NULL;
+}
+
+int am7xxx_open_device(am7xxx_context *ctx, am7xxx_device **dev,
+ unsigned int device_index)
+{
+ int ret;
+
+ if (ctx == NULL) {
+ fprintf(stderr, "%s: context must not be NULL!\n", __func__);
+ return -EINVAL;
+ }
+
+ ret = scan_devices(ctx, SCAN_OP_OPEN_DEVICE, device_index, dev);
+ if (ret < 0) {
+ errno = ENODEV;
+ } else if (ret > 0) {
+ /* warning */
+ fprintf(stderr, "%s: device %d already open\n", __func__, device_index);
+ errno = EBUSY;
+ ret = -EBUSY;
+ }
+
+ return ret;
+}
+
+int am7xxx_close_device(am7xxx_device *dev)
+{
+ if (dev == NULL) {
+ fprintf(stderr, "%s: dev must not be NULL!\n", __func__);
+ return -EINVAL;
+ }
+ if (dev->usb_device) {
+ libusb_release_interface(dev->usb_device, 0);
+ libusb_close(dev->usb_device);
+ dev->usb_device = NULL;
+ }
+ return 0;
+}
+
+int am7xxx_get_device_info(am7xxx_device *dev,
+ unsigned int *native_width,
+ unsigned int *native_height,
+ unsigned int *unknown0,
+ unsigned int *unknown1)
+{
+ int ret;
+ struct am7xxx_header h = {
+ .packet_type = AM7XXX_PACKET_TYPE_DEVINFO,
+ .unknown0 = 0x00,
+ .header_data_len = 0x00,
+ .unknown2 = 0x3e,
+ .unknown3 = 0x10,
+ .header_data = {
+ .devinfo = {
+ .native_width = 0,
+ .native_height = 0,
+ .unknown0 = 0,
+ .unknown1 = 0,
+ },
+ },
+ };
+
+ ret = send_header(dev, &h);
+ if (ret < 0)
+ return ret;
+
+ ret = read_header(dev, &h);
+ if (ret < 0)
+ return ret;
+
+ *native_width = h.header_data.devinfo.native_width;
+ *native_height = h.header_data.devinfo.native_height;
+ *unknown0 = h.header_data.devinfo.unknown0;
+ *unknown1 = h.header_data.devinfo.unknown1;
+
+ return 0;
+}
+
+int am7xxx_send_image(am7xxx_device *dev,