Diff: HIDServiceBase.h

Revision:

0:cfd70fa91663

Child:

1:7a6c2e2c9371

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/HIDServiceBase.h	Tue Sep 15 20:16:58 2015 +0100
@@ -0,0 +1,194 @@
+#ifndef HID_SERVICE_BASE_H_
+#define HID_SERVICE_BASE_H_
+
+#include "mbed.h"
+
+#include "ble/BLE.h"
+#include "HID_types.h"
+
+#define BLE_UUID_DESCRIPTOR_REPORT_REFERENCE 0x2908
+
+typedef const uint8_t report_map_t[];
+typedef const uint8_t * report_t;
+
+typedef struct {
+    uint16_t bcdHID;
+    uint8_t  bCountryCode;
+    uint8_t  flags;
+} HID_information_t;
+
+enum ReportType {
+    INPUT_REPORT    = 0x1,
+    OUTPUT_REPORT   = 0x2,
+    FEATURE_REPORT  = 0x3,
+};
+
+enum ProtocolMode {
+    BOOT_PROTOCOL   = 0x0,
+    REPORT_PROTOCOL = 0x1,
+};
+
+typedef struct {
+    uint8_t ID;
+    uint8_t type;
+} report_reference_t;
+
+
+class HIDServiceBase {
+public:
+    /**
+     *  Constructor
+     *
+     *  @param _ble
+     *         BLE object to add this service to
+     *  @param reportMap
+     *         Byte array representing the input/output report formats. In USB HID jargon, it
+     *         is called "HID report descriptor".
+     *  @param reportMapLength 
+     *         Size of the reportMap array
+     *  @param outputReportLength
+     *         Maximum length of a sent report (up to 64 bytes) (default: 64 bytes)
+     *  @param inputReportLength
+     *         Maximum length of a received report (up to 64 bytes) (default: 64 bytes)
+     *  @param inputReportTickerDelay
+     *         Delay between input report notifications, in ms. Acceptable values depend directly on
+     *         GAP's connInterval parameter, so it shouldn't be less than 12ms
+     *         Preferred GAP connection interval is set after this value, in order to send
+     *         notifications as quick as possible: minimum connection interval will be set to
+     *         (inputReportTickerDelay / 2)
+     */
+    HIDServiceBase(BLE &_ble,
+                   report_map_t reportMap,
+                   uint8_t reportMapLength,
+                   report_t inputReport,
+                   report_t outputReport,
+                   report_t featureReport,
+                   uint8_t inputReportLength = 0,
+                   uint8_t outputReportLength = 0,
+                   uint8_t featureReportLength = 0,
+                   uint8_t inputReportTickerDelay = 50);
+
+    /**
+     *  Send Report
+     *
+     *  @param report   Report to send. Must be of size @ref inputReportLength
+     *  @return         The write status
+     *
+     *  @note Don't call send() directly for multiple reports! Use reportTicker for that, in order
+     *  to avoid overloading the BLE stack, and let it handle events between each report.
+     */
+    virtual ble_error_t send(const report_t report);
+
+    /**
+     *  Read Report
+     *
+     *  @param report   Report to fill. Must be of size @ref outputReportLength
+     *  @return         The read status
+     */
+    virtual ble_error_t read(report_t report);
+
+    /**
+     * Set connection state.
+     *
+     * BLE API doesn't allow to chain onConnection callbacks at the moment, so it is the
+     * application's responsibility to use this method to update connection state.
+
+     * TODO: This is temporary. Remove external calls to setConnected once connection callback
+     * chaining is integrated into BLE API.
+     */
+    virtual void setConnected(bool connected)
+    {
+        this->connected = connected;
+    }
+
+    virtual bool isConnected(void)
+    {
+        return connected;
+    }
+
+protected:
+    /**
+     * Called by BLE API when data has been successfully sent.
+     *
+     * @param count     Number of reports sent
+     *
+     * @note Subclasses can override this to avoid starting the report ticker when there is nothing
+     * to send
+     */
+    virtual void onDataSent(unsigned count);
+
+    /**
+     * Start the ticker that sends input reports at regular interval
+     *
+     * @note reportTickerIsActive describes the state of the ticker and can be used by HIDS
+     * implementations.
+     */
+    virtual void startReportTicker(void);
+
+    /**
+     * Stop the input report ticker
+     */
+    virtual void stopReportTicker(void);
+
+    /**
+     * Called by input report ticker at regular interval (reportTickerDelay). This must be
+     * overriden by HIDS implementations to call the @ref send() with a report, if necessary.
+     */
+    virtual void sendCallback(void) = 0;
+
+    /**
+     * Create the Gatt descriptor for a report characteristic
+     */
+    GattAttribute** inputReportDescriptors();
+    GattAttribute** outputReportDescriptors();
+    GattAttribute** featureReportDescriptors();
+
+    /**
+     * Create the HID information structure
+     */
+    HID_information_t* HIDInformation();
+
+protected:
+    BLE &ble;
+    bool connected;
+
+    int reportMapLength;
+
+    report_t inputReport;
+    report_t outputReport;
+    report_t featureReport;
+
+    uint8_t inputReportLength;
+    uint8_t outputReportLength;
+    uint8_t featureReportLength;
+
+    uint8_t controlPointCommand;
+    uint8_t protocolMode;
+
+    report_reference_t inputReportReferenceData;
+    report_reference_t outputReportReferenceData;
+    report_reference_t featureReportReferenceData;
+
+    GattAttribute inputReportReferenceDescriptor;
+    GattAttribute outputReportReferenceDescriptor;
+    GattAttribute featureReportReferenceDescriptor;
+
+    // Optional gatt characteristics:
+    GattCharacteristic protocolModeCharacteristic;
+
+    // Report characteristics (each sort of optional)
+    GattCharacteristic inputReportCharacteristic;
+    GattCharacteristic outputReportCharacteristic;
+    GattCharacteristic featureReportCharacteristic;
+
+    // Required gatt characteristics: Report Map, Information, Control Point
+    GattCharacteristic reportMapCharacteristic;
+    ReadOnlyGattCharacteristic<HID_information_t> HIDInformationCharacteristic;
+    GattCharacteristic HIDControlPointCharacteristic;
+
+    Ticker reportTicker;
+    uint32_t reportTickerDelay;
+    bool reportTickerIsActive;
+};
+
+#endif /* !HID_SERVICE_BASE_H_ */