Make HID device class driver ignore the previous HID report comparison buffer when...

[pub/USBasp.git] / LUFA / Drivers / USB / Class / Device / HID.h

diff --git a/LUFA/Drivers/USB/Class/Device/HID.h b/LUFA/Drivers/USB/Class/Device/HID.h
index dee892d..4865a12 100644 (file)
--- a/LUFA/Drivers/USB/Class/Device/HID.h
+++ b/LUFA/Drivers/USB/Class/Device/HID.h
@@ -77,7 +77,14 @@
                                        void*    PrevReportINBuffer; /** Pointer to a buffer where the previously created HID input report can be\r
                                                                      *  stored by the driver, for comparison purposes to detect report changes that\r
                                                                      *  must be sent immediately to the host. This should point to a buffer big enough\r
                                        void*    PrevReportINBuffer; /** Pointer to a buffer where the previously created HID input report can be\r
                                                                      *  stored by the driver, for comparison purposes to detect report changes that\r
                                                                      *  must be sent immediately to the host. This should point to a buffer big enough\r

-                                                                     *  to hold the largest HID input report sent from the HID interface.\r
+                                                                     *  to hold the largest HID input report sent from the HID interface. If this is set\r
+                                                                                                 *  to NULL, it is up to the user to force transfers when needed in the \r
+                                                                                                 *  \ref CALLBACK_HID_Device_CreateHIDReport() callback function.\r
+                                                                                                 *\r
+                                                                                                 *  \note Due to the single buffer, the internal driver can only correctly compare\r
+                                                                                                 *        subsequent reports with identical report IDs. In multiple report devices,\r
+                                                                                                 *        this buffer should be set to NULL and the decision to send reports made\r
+                                                                                                 *        by the user application instead.\r

                                                                      */\r
                                        uint8_t  PrevReportINBufferSize; /** Size in bytes of the given input report buffer. This is used to create a\r
                                                                          *  second buffer of the same size within the driver so that subsequent reports\r
                                                                      */\r
                                        uint8_t  PrevReportINBufferSize; /** Size in bytes of the given input report buffer. This is used to create a\r
                                                                          *  second buffer of the same size within the driver so that subsequent reports\r