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.).

1 files changed, 12 insertions, 3 deletions

diff --git a/Demos/Device/ClassDriver/Joystick/Joystick.c b/Demos/Device/ClassDriver/Joystick/Joystick.c
index ffd167ef5..f4dc32d9b 100644
--- a/Demos/Device/ClassDriver/Joystick/Joystick.c
+++ b/Demos/Device/ClassDriver/Joystick/Joystick.c
@@ -36,6 +36,9 @@
 

 #include "Joystick.h"

 

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

+uint8_t PrevJoystickHIDReportBuffer[sizeof(USB_JoystickReport_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.

@@ -48,6 +51,9 @@ USB_ClassInfo_HID_Device_t Joystick_HID_Interface =
 

 				.ReportINEndpointNumber  = JOYSTICK_EPNUM,

 				.ReportINEndpointSize    = JOYSTICK_EPSIZE,

+

+				.PrevReportINBuffer      = PrevJoystickHIDReportBuffer,

+				.PrevReportINBufferSize  = sizeof(PrevJoystickHIDReportBuffer),

 			},

 	};

 

@@ -128,10 +134,12 @@ ISR(TIMER0_COMPA_vect, ISR_BLOCK)
  *  \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 written in the report (or zero if no report is to be sent

+ *  \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_JoystickReport_Data_t* JoystickReport = (USB_JoystickReport_Data_t*)ReportData;

 	

@@ -154,7 +162,8 @@ uint16_t CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const H
 	if (ButtonStatus_LCL & BUTTONS_BUTTON1)

 	  JoystickReport->Button |= (1 << 0);

 	  

-	return sizeof(USB_JoystickReport_Data_t);

+	*ReportSize = sizeof(USB_JoystickReport_Data_t);

+	return false;

 }

 

 /** HID class driver callback function for the processing of HID reports from the host.