1 files changed, 111 insertions, 0 deletions
diff --git a/Demos/Host/LowLevel/JoystickHostWithParser/HIDReport.c b/Demos/Host/LowLevel/JoystickHostWithParser/HIDReport.c
new file mode 100644
index 0000000000..dadbb395de
--- /dev/null
+++ b/Demos/Host/LowLevel/JoystickHostWithParser/HIDReport.c
@@ -0,0 +1,111 @@
+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2017.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2017  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
+  software without specific, written prior permission.
+
+  The author disclaims all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+#include "HIDReport.h"
+
+/** Size in bytes of the attached device's HID report descriptor */
+uint16_t         HIDReportSize;
+
+/** Processed HID report descriptor items structure, containing information on each HID report element */
+HID_ReportInfo_t HIDReportInfo;
+
+
+/** Function to read in the HID report descriptor from the attached device, and process it into easy-to-read
+ *  structures via the HID parser routines in the LUFA library.
+ *
+ *  \return  A value from the \ref JoystickHostWithParser_GetHIDReportDataCodes_t enum
+ */
+uint8_t GetHIDReportData(void)
+{
+	/* Create a buffer big enough to hold the entire returned HID report */
+	uint8_t HIDReportData[HIDReportSize];
+
+	USB_ControlRequest = (USB_Request_Header_t)
+		{
+			.bmRequestType = (REQDIR_DEVICETOHOST | REQTYPE_STANDARD | REQREC_INTERFACE),
+			.bRequest      = REQ_GetDescriptor,
+			.wValue        = (HID_DTYPE_Report << 8),
+			.wIndex        = 0,
+			.wLength       = HIDReportSize,
+		};
+
+	/* Select the control pipe for the request transfer */
+	Pipe_SelectPipe(PIPE_CONTROLPIPE);
+
+	/* Send control request to retrieve the HID report from the attached device */
+	if (USB_Host_SendControlRequest(HIDReportData) != HOST_SENDCONTROL_Successful)
+	  return ParseControlError;
+
+	/* Send the HID report to the parser for processing */
+	if (USB_ProcessHIDReport(HIDReportData, HIDReportSize, &HIDReportInfo) != HID_PARSE_Successful)
+	  return ParseError;
+
+	return ParseSuccessful;
+}
+
+/** Callback for the HID Report Parser. This function is called each time the HID report parser is about to store
+ *  an IN, OUT or FEATURE item into the HIDReportInfo structure. To save on RAM, we are able to filter out items
+ *  we aren't interested in (preventing us from being able to extract them later on, but saving on the RAM they would
+ *  have occupied).
+ *
+ *  \param[in] CurrentItem  Pointer to the item the HID report parser is currently working with
+ *
+ *  \return Boolean \c true if the item should be stored into the HID report structure, \c false if it should be discarded
+ */
+bool CALLBACK_HIDParser_FilterHIDReportItem(HID_ReportItem_t* const CurrentItem)
+{
+	bool IsJoystick = false;
+
+	/* Iterate through the item's collection path, until either the root collection node or a collection with the
+	 * Joystick Usage is found - this prevents Mice, which use identical descriptors except for the Mouse usage
+	 * parent node, from being erroneously treated as a joystick
+	 */
+	for (HID_CollectionPath_t* CurrPath = CurrentItem->CollectionPath; CurrPath != NULL; CurrPath = CurrPath->Parent)
+	{
+		if ((CurrPath->Usage.Page  == USAGE_PAGE_GENERIC_DCTRL) &&
+		    (CurrPath->Usage.Usage == USAGE_JOYSTICK))
+		{
+			IsJoystick = true;
+			break;
+		}
+	}
+
+	/* If a collection with the joystick usage was not found, indicate that we are not interested in this item */
+	if (!IsJoystick)
+	  return false;
+
+	/* Check the attributes of the current joystick item - see if we are interested in it or not;
+	 * only store BUTTON and GENERIC_DESKTOP_CONTROL items into the Processed HID Report
+	 * structure to save RAM and ignore the rest
+	 */
+	return ((CurrentItem->Attributes.Usage.Page == USAGE_PAGE_BUTTON) ||
+	        (CurrentItem->Attributes.Usage.Page == USAGE_PAGE_GENERIC_DCTRL));
+}
+