HID-over-GATT implementation with the BLE API. This library allows to create devices such as mouse, keyboard or joystick, over Bluetooth Low Energy.
Dependents: Seeed_Tiny_BLE_FTHR_Peripheral
Fork of BLE_HID by
Diff: HIDServiceBase.cpp
- Revision:
- 0:cfd70fa91663
- Child:
- 1:7a6c2e2c9371
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/HIDServiceBase.cpp Tue Sep 15 20:16:58 2015 +0100 @@ -0,0 +1,199 @@ +#include "mbed.h" +#include "HIDServiceBase.h" + +HIDServiceBase::HIDServiceBase(BLE &_ble, + report_map_t reportMap, + uint8_t reportMapSize, + report_t inputReport, + report_t outputReport, + report_t featureReport, + uint8_t inputReportLength, + uint8_t outputReportLength, + uint8_t featureReportLength, + uint8_t inputReportTickerDelay) : + ble(_ble), + connected (false), + reportMapLength(reportMapSize), + + inputReport(inputReport), + outputReport(outputReport), + featureReport(featureReport), + + inputReportLength(inputReportLength), + outputReportLength(outputReportLength), + featureReportLength(featureReportLength), + + protocolMode(REPORT_PROTOCOL), + + inputReportReferenceDescriptor(BLE_UUID_DESCRIPTOR_REPORT_REFERENCE, + (uint8_t *)&inputReportReferenceData, 2, 2), + outputReportReferenceDescriptor(BLE_UUID_DESCRIPTOR_REPORT_REFERENCE, + (uint8_t *)&outputReportReferenceData, 2, 2), + featureReportReferenceDescriptor(BLE_UUID_DESCRIPTOR_REPORT_REFERENCE, + (uint8_t *)&featureReportReferenceData, 2, 2), + + protocolModeCharacteristic(GattCharacteristic::UUID_PROTOCOL_MODE_CHAR, &protocolMode, 1, 1, + GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ + | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE_WITHOUT_RESPONSE), + + inputReportCharacteristic(GattCharacteristic::UUID_REPORT_CHAR, + (uint8_t *)inputReport, inputReportLength, inputReportLength, + GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ + | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY + | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE, + inputReportDescriptors(), 1), + + outputReportCharacteristic(GattCharacteristic::UUID_REPORT_CHAR, + (uint8_t *)outputReport, outputReportLength, outputReportLength, + GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ + | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE_WITHOUT_RESPONSE + | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE, + outputReportDescriptors(), 1), + + featureReportCharacteristic(GattCharacteristic::UUID_REPORT_CHAR, + (uint8_t *)featureReport, featureReportLength, featureReportLength, + GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ + | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE, + featureReportDescriptors(), 1), + + /* + * We need to set reportMap content as const, in order to let the compiler put it into flash + * instead of RAM. The characteristic is read-only so it won't be written, but + * GattCharacteristic constructor takes non-const arguments only. Hence the cast. + */ + reportMapCharacteristic(GattCharacteristic::UUID_REPORT_MAP_CHAR, + const_cast<uint8_t*>(reportMap), reportMapLength, reportMapLength, + GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ), + + HIDInformationCharacteristic(GattCharacteristic::UUID_HID_INFORMATION_CHAR, HIDInformation()), + HIDControlPointCharacteristic(GattCharacteristic::UUID_HID_CONTROL_POINT_CHAR, + &controlPointCommand, 1, 1, + GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE_WITHOUT_RESPONSE), + + reportTickerDelay(inputReportTickerDelay), + reportTickerIsActive(false) +{ + static GattCharacteristic *characteristics[] = { + &HIDInformationCharacteristic, + &reportMapCharacteristic, + &protocolModeCharacteristic, + &HIDControlPointCharacteristic, + NULL, + NULL, + NULL, + NULL, + NULL + }; + + unsigned int charIndex = 4; + /* + * Report characteristics are optional, and depend on the reportMap descriptor + * Note: at least one should be present, but we don't check that at the moment. + */ + if (inputReportLength) + characteristics[charIndex++] = &inputReportCharacteristic; + if (outputReportLength) + characteristics[charIndex++] = &outputReportCharacteristic; + if (featureReportLength) + characteristics[charIndex++] = &featureReportCharacteristic; + + /* TODO: let children add some more characteristics, namely boot keyboard and mouse (They are + * mandatory as per HIDS spec.) Ex: + * + * addExtraCharacteristics(characteristics, int& charIndex); + */ + + GattService service(GattService::UUID_HUMAN_INTERFACE_DEVICE_SERVICE, + characteristics, charIndex); + + ble.addService(service); + + ble.onDataSent(this, &HIDServiceBase::onDataSent); + + /* + * Change preferred connection params, in order to optimize the notification frequency. Most + * OSes seem to respect this, even though they are not required to. + * + * Some OSes don't handle reconnection well, at the moment, so we set the maximum possible + * timeout, 32 seconds + */ + uint16_t minInterval = Gap::MSEC_TO_GAP_DURATION_UNITS(reportTickerDelay / 2); + if (minInterval < 6) + minInterval = 6; + uint16_t maxInterval = minInterval * 2; + Gap::ConnectionParams_t params = {minInterval, maxInterval, 0, 3200}; + + ble.gap().setPreferredConnectionParams(¶ms); + + SecurityManager::SecurityMode_t securityMode = SecurityManager::SECURITY_MODE_ENCRYPTION_NO_MITM; + protocolModeCharacteristic.requireSecurity(securityMode); + reportMapCharacteristic.requireSecurity(securityMode); + inputReportCharacteristic.requireSecurity(securityMode); + outputReportCharacteristic.requireSecurity(securityMode); + featureReportCharacteristic.requireSecurity(securityMode); +} + +void HIDServiceBase::startReportTicker(void) { + if (reportTickerIsActive) + return; + reportTicker.attach_us(this, &HIDServiceBase::sendCallback, reportTickerDelay * 1000); + reportTickerIsActive = true; +} + +void HIDServiceBase::stopReportTicker(void) { + reportTicker.detach(); + reportTickerIsActive = false; +} + +void HIDServiceBase::onDataSent(unsigned count) { + startReportTicker(); +} + +GattAttribute** HIDServiceBase::inputReportDescriptors() { + inputReportReferenceData.ID = 0; + inputReportReferenceData.type = INPUT_REPORT; + + static GattAttribute * descs[] = { + &inputReportReferenceDescriptor, + }; + return descs; +} + +GattAttribute** HIDServiceBase::outputReportDescriptors() { + outputReportReferenceData.ID = 0; + outputReportReferenceData.type = OUTPUT_REPORT; + + static GattAttribute * descs[] = { + &outputReportReferenceDescriptor, + }; + return descs; +} + +GattAttribute** HIDServiceBase::featureReportDescriptors() { + featureReportReferenceData.ID = 0; + featureReportReferenceData.type = FEATURE_REPORT; + + static GattAttribute * descs[] = { + &featureReportReferenceDescriptor, + }; + return descs; +} + + +HID_information_t* HIDServiceBase::HIDInformation() { + static HID_information_t info = {HID_VERSION_1_11, 0x00, 0x03}; + + return &info; +} + +ble_error_t HIDServiceBase::send(const report_t report) { + return ble.gattServer().write(inputReportCharacteristic.getValueHandle(), + report, + inputReportLength); +} + +ble_error_t HIDServiceBase::read(report_t report) { + // TODO. For the time being, we'll just have HID input reports... + return BLE_ERROR_NOT_IMPLEMENTED; +} +