Fix demos based on the device mode HID class driver, as well as the driver itself. Changed HID device class driver to require the user to give a buffer and size to hold the previously generated report, for comparison purposes, and altered the prototype of the CALLBACK_HID_Device_CreateHIDReport() function so that reports can be sent to the host even if there are no apparent changes (useful for relative movements in mice, etc.).

2 files changed, 20 insertions, 11 deletions

diff --git a/Projects/Magstripe/Magstripe.c b/Projects/Magstripe/Magstripe.c
index 6d463d6a8..f0fd8a7d0 100644
--- a/Projects/Magstripe/Magstripe.c
+++ b/Projects/Magstripe/Magstripe.c
@@ -45,6 +45,9 @@ BitBuffer_t TrackDataBuffers[TOTAL_TRACKS];
 /** Pointer to the current track buffer being sent to the host. */

 BitBuffer_t* CurrentTrackBuffer = &TrackDataBuffers[TOTAL_TRACKS];

 

+/** Buffer to hold the previously generated Keyboard HID report, for comparison purposes inside the HID class driver. */

+uint8_t PrevKeyboardHIDReportBuffer[sizeof(USB_KeyboardReport_Data_t)];

+

 /** LUFA HID Class driver interface configuration and state information. This structure is

  *  passed to all HID Class driver functions, so that multiple instances of the same class

  *  within a device can be differentiated from one another.

@@ -57,6 +60,9 @@ USB_ClassInfo_HID_Device_t Keyboard_HID_Interface =
 

 				.ReportINEndpointNumber  = KEYBOARD_EPNUM,

 				.ReportINEndpointSize    = KEYBOARD_EPSIZE,

+

+				.PrevReportINBuffer      = PrevKeyboardHIDReportBuffer,

+				.PrevReportINBufferSize  = sizeof(PrevKeyboardHIDReportBuffer),

 			},

 	};

 

@@ -156,15 +162,17 @@ ISR(TIMER0_COMPA_vect, ISR_BLOCK)
 	HID_Device_MillisecondElapsed(&Keyboard_HID_Interface);

 }

 

-/** HID Class driver callback function for the creation of a HID report for the host.

+/** HID class driver callback function for the creation of HID reports to the host.

  *

- *  \param[in] HIDInterfaceInfo  Pointer to the HID interface structure for the HID interface being referenced

- *  \param[in,out] ReportID      Report ID requested by the host if non-zero, otherwise callback should set to the generated report ID

- *  \param[out] ReportData       Pointer to the preallocated report buffer where the created report should be stored

+ *  \param[in] HIDInterfaceInfo  Pointer to the HID class interface configuration structure being referenced

+ *  \param[in,out] ReportID  Report ID requested by the host if non-zero, otherwise callback should set to the generated report ID

+ *  \param[out] ReportData  Pointer to a buffer where the created report should be stored

+ *  \param[out] ReportSize  Number of bytes written in the report (or zero if no report is to be sent

  *

- *  \return Number of bytes in the created report

+ *  \return Boolean true to force the sending of the report, false to let the library determine if it needs to be sent

  */

-uint16_t CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const HIDInterfaceInfo, uint8_t* const ReportID, void* ReportData)

+bool CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const HIDInterfaceInfo, uint8_t* const ReportID,

+                                         void* ReportData, uint16_t* ReportSize)

 {

 	USB_KeyboardReport_Data_t* KeyboardReport = (USB_KeyboardReport_Data_t*)ReportData;

 

@@ -190,7 +198,8 @@ uint16_t CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const H
 		KeyboardReport->KeyCode = BitBuffer_GetNextBit(CurrentTrackBuffer) ? KEY_1 : KEY_0;

 	}

 	

-	return sizeof(USB_KeyboardReport_Data_t);

+	*ReportSize = sizeof(USB_KeyboardReport_Data_t);

+	return false;

 }

 

 /** HID Class driver callback function for the processing of a received HID report from the host.

diff --git a/Projects/Magstripe/Magstripe.h b/Projects/Magstripe/Magstripe.h
index 4e0aac979..279e3db2e 100644
--- a/Projects/Magstripe/Magstripe.h
+++ b/Projects/Magstripe/Magstripe.h
@@ -85,9 +85,9 @@
 		void EVENT_USB_ConfigurationChanged(void);

 		void EVENT_USB_UnhandledControlPacket(void);

 

-		uint16_t CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const HIDInterfaceInfo, uint8_t* const ReportID,

-		                                             void* ReportData);

-		void CALLBACK_HID_Device_ProcessHIDReport(USB_ClassInfo_HID_Device_t* const HIDInterfaceInfo, const uint8_t ReportID,

-                                                  const void* ReportData, const uint16_t ReportSize);

+		bool CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const HIDInterfaceInfo, uint8_t* const ReportID,

+                                                 void* ReportData, uint16_t* ReportSize);

+		void CALLBACK_HID_Device_ProcessHIDReport(USB_ClassInfo_HID_Device_t* const HIDInterfaceInfo, const uint8_t ReportID, 

+		                                          const void* ReportData, const uint16_t ReportSize);

 														  

 #endif