char* usb_device_get_serial(struct usb_device *device)
{
struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc;
if (desc->iSerialNumber)
return usb_device_get_string(device, desc->iSerialNumber);
else
return NULL;
}
char* usb_device_get_manufacturer_name(struct usb_device *device)
{
struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc;
if (desc->iManufacturer)
return usb_device_get_string(device, desc->iManufacturer);
else
return NULL;
}
char* usb_device_get_product_name(struct usb_device *device)
{
struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc;
if (desc->iProduct)
return usb_device_get_string(device, desc->iProduct);
else
return NULL;
}
static const char *get_str(struct usb_device *dev, int id)
{
char *str = usb_device_get_string(dev, id);
if (id && str) {
strlcpy(str_buff, str, sizeof(str_buff));
free(str);
} else {
snprintf(str_buff, sizeof(str_buff), "%02x", id);
}
return str_buff;
}
MtpDevice* MtpDevice::open(const char* deviceName, int fd) {
struct usb_device *device = usb_device_new(deviceName, fd);
if (!device) {
ALOGE("usb_device_new failed for %s", deviceName);
return NULL;
}
struct usb_descriptor_header* desc;
struct usb_descriptor_iter iter;
usb_descriptor_iter_init(device, &iter);
while ((desc = usb_descriptor_iter_next(&iter)) != NULL) {
if (desc->bDescriptorType == USB_DT_INTERFACE) {
struct usb_interface_descriptor *interface = (struct usb_interface_descriptor *)desc;
if (interface->bInterfaceClass == USB_CLASS_STILL_IMAGE &&
interface->bInterfaceSubClass == 1 && // Still Image Capture
interface->bInterfaceProtocol == 1) // Picture Transfer Protocol (PIMA 15470)
{
char* manufacturerName = usb_device_get_manufacturer_name(device);
char* productName = usb_device_get_product_name(device);
ALOGD("Found camera: \"%s\" \"%s\"\n", manufacturerName, productName);
free(manufacturerName);
free(productName);
} else if (interface->bInterfaceClass == 0xFF &&
interface->bInterfaceSubClass == 0xFF &&
interface->bInterfaceProtocol == 0) {
char* interfaceName = usb_device_get_string(device, interface->iInterface);
if (!interfaceName) {
continue;
} else if (strcmp(interfaceName, "MTP")) {
free(interfaceName);
continue;
}
free(interfaceName);
// Looks like an android style MTP device
char* manufacturerName = usb_device_get_manufacturer_name(device);
char* productName = usb_device_get_product_name(device);
ALOGD("Found MTP device: \"%s\" \"%s\"\n", manufacturerName, productName);
free(manufacturerName);
free(productName);
}
#if 0
else {
// look for special cased devices based on vendor/product ID
// we are doing this mainly for testing purposes
uint16_t vendor = usb_device_get_vendor_id(device);
uint16_t product = usb_device_get_product_id(device);
if (!isMtpDevice(vendor, product)) {
// not an MTP or PTP device
continue;
}
// request MTP OS string and descriptor
// some music players need to see this before entering MTP mode.
char buffer[256];
memset(buffer, 0, sizeof(buffer));
int ret = usb_device_control_transfer(device,
USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_STANDARD,
USB_REQ_GET_DESCRIPTOR, (USB_DT_STRING << 8) | 0xEE,
0, buffer, sizeof(buffer), 0);
printf("usb_device_control_transfer returned %d errno: %d\n", ret, errno);
if (ret > 0) {
printf("got MTP string %s\n", buffer);
ret = usb_device_control_transfer(device,
USB_DIR_IN|USB_RECIP_DEVICE|USB_TYPE_VENDOR, 1,
0, 4, buffer, sizeof(buffer), 0);
printf("OS descriptor got %d\n", ret);
} else {
printf("no MTP string\n");
}
}
#endif
// if we got here, then we have a likely MTP or PTP device
// interface should be followed by three endpoints
struct usb_endpoint_descriptor *ep;
struct usb_endpoint_descriptor *ep_in_desc = NULL;
struct usb_endpoint_descriptor *ep_out_desc = NULL;
struct usb_endpoint_descriptor *ep_intr_desc = NULL;
for (int i = 0; i < 3; i++) {
ep = (struct usb_endpoint_descriptor *)usb_descriptor_iter_next(&iter);
if (!ep || ep->bDescriptorType != USB_DT_ENDPOINT) {
ALOGE("endpoints not found\n");
usb_device_close(device);
return NULL;
}
if (ep->bmAttributes == USB_ENDPOINT_XFER_BULK) {
if (ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK)
ep_in_desc = ep;
else
ep_out_desc = ep;
} else if (ep->bmAttributes == USB_ENDPOINT_XFER_INT &&
ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK) {
ep_intr_desc = ep;
}
}
if (!ep_in_desc || !ep_out_desc || !ep_intr_desc) {
ALOGE("endpoints not found\n");
usb_device_close(device);
return NULL;
}
if (usb_device_claim_interface(device, interface->bInterfaceNumber)) {
ALOGE("usb_device_claim_interface failed errno: %d\n", errno);
usb_device_close(device);
return NULL;
}
MtpDevice* mtpDevice = new MtpDevice(device, interface->bInterfaceNumber,
ep_in_desc, ep_out_desc, ep_intr_desc);
mtpDevice->initialize();
return mtpDevice;
}
}
usb_device_close(device);
ALOGE("device not found");
return NULL;
}
