I am trying to use the AOA 2.0 protocol and libusb to send key presses to an Android device. I am able to put the device accessory mode and and able to register the HID device. However whenever I send an event I get the error:
libusb: debug [handle_control_completion] unsupported control request
I think my problem may be the hid descriptor that I am sending, however I found one online that should work.
Here is my relevant code with the descriptor:
char DESC[] = {
0x05, 0x01, /* Usage Page (Generic Desktop) */
0x09, 0x06, /* Usage (Keyboard) */
0xA1, 0x01, /* Collection (Application) */
0x05, 0x07, /* Usage Page (Keyboard) */
0x19, 224, /* Usage Minimum (224) */
0x29, 231, /* Usage Maximum (231) */
0x15, 0x00, /* Logical Minimum (0) */
0x25, 0x01, /* Logical Maximum (1) */
0x75, 0x01, /* Report Size (1) */
0x95, 0x08, /* Report Count (8) */
0x81, 0x02, /* Input (Data, Variable, Absolute) */
0x81, 0x01, /* Input (Constant) */
0x19, 0x00, /* Usage Minimum (0) */
0x29, 101, /* Usage Maximum (101) */
0x15, 0x00, /* Logical Minimum (0) */
0x25, 101, /* Logical Maximum (101) */
0x75, 0x08, /* Report Size (8) */
0x95, 0x06, /* Report Count (6) */
0x81, 0x00, /* Input (Data, Array) */
0x05, 0x08, /* Usage Page (LED) */
0x19, 0x01, /* Usage Minimum (1) */
0x29, 0x05, /* Usage Maximum (5) */
0x15, 0x00, /* Logical Minimum (0) */
0x25, 0x01, /* Logical Maximum (1) */
0x75, 0x01, /* Report Size (1) */
0x95, 0x05, /* Report Count (5) */
0x91, 0x02, /* Output (Data, Variable, Absolute) */
0x95, 0x03, /* Report Count (3) */
0x91, 0x01, /* Output (Constant) */
0xC0 /* End Collection */
};
int response;
//Register the HID device
response = libusb_control_transfer(handle, 0x40, 54, 1, sizeof(DESC), NULL, 0, 0);
if (response < 0) {error(response); return -1;}
// Send the device descriptor
response = libusb_control_transfer(handle, 0x40, 56, 1, 0, DESC, sizeof(DESC), 0);
if (response < 0) {error(response); return -1;}
usleep(1000);
// OK so here is the problem, this request should just send the next song ket
// However I am getting unsupported control request.
char report[] = {0x07,0x00,0xEC,0x00,0x00,0x00,0x00,0x00};
response = libusb_control_transfer(handle, 0x40, 57, 1, 0, report, sizeof(report), 0);
if (response < 0) {error(response); return -1;}
return 0;
EDIT: Ok so I did some more digging around in the android adk code and I found a generic keyboard descriptor with some sample code. Now it seems to not fail like one out of every 10ish attempts which is very weird? I updated the code as well.
My problem was that I did not sleep long enough after sending the device descriptor.
usleep(100000);
Fixed it