/*!@brief Initialize libhid: scan for USB busses and devices using libusb.
*
* Call this routine before making any other libhid calls.
*
* @return HID_RET_SUCCESS if everything was properly initialized.
*/
hid_return hid_init()
{
if (hid_is_initialised()) {
ERROR("cannot initialised already initialised HID library");
return HID_RET_ALREADY_INITIALISED;
}
/* Include version to make deciphering logfiles easier: */
NOTICE(PACKAGE_STRING " is being initialized.");
TRACE("initialising USB subsystem...");
usb_init();
TRACE("scanning for USB busses...");
if (usb_find_busses() < 0) {
ERROR("failed to scan for USB busses");
return HID_RET_FAIL_FIND_BUSSES;
}
TRACE("scanning for USB devices...");
if (usb_find_devices() < 0) {
ERROR("failed to scan for USB devices");
return HID_RET_FAIL_FIND_DEVICES;
}
initialised = true;
NOTICE("successfully initialised HID library.");
return HID_RET_SUCCESS;
}
/*!@brief Complement to hid_init(): cleans up after libhid.
*/
hid_return hid_cleanup()
{
if (!hid_is_initialised()) {
ERROR("cannot cleanup uninitialised HID library.");
return HID_RET_NOT_INITIALISED;
}
initialised = false;
NOTICE("successfully deinitialised HID library.");
return HID_RET_SUCCESS;
}
static t_int init_libhid(t_usbhid *x)
{
if (! hid_is_initialised() )
{
x->x_hid_return = hid_init();
if(x->x_hid_return != HID_RET_SUCCESS)
{
error("[usbhid] hid_init failed with return code %d\n",
x->x_hid_return);
}
}
return(x->x_hid_return);
}
/*!@brief Retrieve a numeric input item
*
* @param[in] hidif Which interface to send to
* @param[in] path Path to input item
* @param[in] depth See hid_find_object()
* @param[out] value Result from hid_extract_value()
*
* @todo Handle exponent and unit conversion (separate library?)
*/
hid_return hid_get_item_value(HIDInterface* const hidif, int const path[],
unsigned int const depth, double *const value)
{
ASSERT(hid_is_initialised());
ASSERT(hid_is_opened(hidif));
unsigned int size;
unsigned char buffer[32]; /*! @todo Dynamically allocate the item buffer */
if (!hid_is_opened(hidif)) {
WARNING("the device has not been opened.");
return HID_RET_DEVICE_NOT_OPENED;
}
TRACE("retrieving report from USB device %s...", hidif->id);
hidif->hid_data->Type = ITEM_FEATURE;
hidif->hid_data->ReportID = 0;
/* TODO: i think this and the buffer stuff should be passed in */
hid_find_object(hidif, path, depth);
hid_get_report_size(hidif, hidif->hid_data->ReportID,
hidif->hid_data->Type, &size);
ASSERT(size <= 32); /* remove when buffer situation is fixed. */
int len = usb_control_msg(hidif->dev_handle,
USB_ENDPOINT_IN + USB_TYPE_CLASS + USB_RECIP_INTERFACE,
HID_REPORT_GET,
hidif->hid_data->ReportID + (HID_RT_FEATURE << 8),
hidif->interface,
(char*)buffer, size, USB_TIMEOUT);
if (len < 0) {
WARNING("failed to retrieve report from USB device %s:%s.", hidif->id,usb_strerror());
return HID_RET_FAIL_GET_REPORT;
}
if ((unsigned)len != size) {
WARNING("failed to retrieve complete report from USB device %s; "
"requested: %d bytes, got: %d bytes.", hidif->id,
size, len);
return HID_RET_FAIL_GET_REPORT;
}
if (hid_extract_value(hidif, buffer, value) != HID_RET_SUCCESS) {
return HID_RET_FAIL_GET_REPORT;
}
NOTICE("successfully retrieved report from USB device %s.", hidif->id);
return HID_RET_SUCCESS;
}
/*!@brief Send an entire output report to the device
*
* This routine uses a control message to send the report. To use an interrupt
* endpoint, use hid_interrupt_write().
*
* @param[in] hidif Which interface to send to
* @param[in] path Path to an output item (to find Report ID)
* @param[in] depth See hid_find_object()
* @param[in] buffer Output Report
* @param[in] size How many bytes to send
*/
hid_return hid_set_output_report(HIDInterface* const hidif, int const path[],
unsigned int const depth, char const* const buffer, unsigned int const size)
{
ASSERT(hid_is_initialised());
ASSERT(hid_is_opened(hidif));
ASSERT(buffer);
if (!buffer) return HID_RET_INVALID_PARAMETER;
if (!hid_is_opened(hidif)) {
WARNING("the device has not been opened.");
return HID_RET_DEVICE_NOT_OPENED;
}
TRACE("looking up report ID...");
hidif->hid_data->Type = ITEM_OUTPUT;
hidif->hid_data->ReportID = 0;
hid_find_object(hidif, path, depth);
TRACE("sending report ID 0x%02x (length: %d) to USB device %s...",
hidif->hid_data->ReportID, size, hidif->id);
int len = usb_control_msg(hidif->dev_handle,
USB_ENDPOINT_OUT + USB_TYPE_CLASS + USB_RECIP_INTERFACE,
HID_REPORT_SET,
hidif->hid_data->ReportID + (HID_RT_OUTPUT << 8),
hidif->interface,
(char*)buffer, size, USB_TIMEOUT);
if (len < 0) {
WARNING("failed to send report to USB device %s:%s.", hidif->id,usb_strerror());
return HID_RET_FAIL_SET_REPORT;
}
if (len != (signed)size) {
WARNING("failed to send complete report to USB device %s; "
"requested: %d bytes, sent: %d bytes.", hidif->id,
size, len);
return HID_RET_FAIL_SET_REPORT;
}
NOTICE("successfully sent report to USB device %s.", hidif->id);
return HID_RET_SUCCESS;
}