Changed the signature of the CALLBACK_USB_GetDescriptor() callback function so that the descriptor pointer is const, to remove the need for extra casting inside the callback (thanks to Jonathan Kollasch).

4 files changed, 25 insertions, 22 deletions

diff --git a/Demos/Device/Incomplete/Sideshow/Descriptors.c b/Demos/Device/Incomplete/Sideshow/Descriptors.c
index a3f28b58d..d10bcc8ab 100644
--- a/Demos/Device/Incomplete/Sideshow/Descriptors.c
+++ b/Demos/Device/Incomplete/Sideshow/Descriptors.c
@@ -156,48 +156,48 @@ USB_OSCompatibleIDDescriptor_t PROGMEM DevCompatIDs =
 
 uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue,
                                     const uint8_t wIndex,
-                                    void** const DescriptorAddress)
+                                    const void** const DescriptorAddress)
 {
 	const uint8_t  DescriptorType   = (wValue >> 8);
 	const uint8_t  DescriptorNumber = (wValue & 0xFF);
 
-	void*    Address = NULL;
-	uint16_t Size    = NO_DESCRIPTOR;
+	const void* Address = NULL;
+	uint16_t    Size    = NO_DESCRIPTOR;
 
 	switch (DescriptorType)
 	{
 		case DTYPE_Device:
-			Address = (void*)&DeviceDescriptor;
+			Address = &DeviceDescriptor;
 			Size    = sizeof(USB_Descriptor_Device_t);
 			break;
 		case DTYPE_Configuration:
-			Address = (void*)&ConfigurationDescriptor;
+			Address = &ConfigurationDescriptor;
 			Size    = sizeof(USB_Descriptor_Configuration_t);
 			break;
 		case DTYPE_String:
 			switch (DescriptorNumber)
 			{
 				case 0x00:
-					Address = (void*)&LanguageString;
+					Address = &LanguageString;
 					Size    = pgm_read_byte(&LanguageString.Header.Size);
 					break;
 				case 0x01:
-					Address = (void*)&ManufacturerString;
+					Address = &ManufacturerString;
 					Size    = pgm_read_byte(&ManufacturerString.Header.Size);
 					break;
 				case 0x02:
-					Address = (void*)&ProductString;
+					Address = &ProductString;
 					Size    = pgm_read_byte(&ProductString.Header.Size);
 					break;
 				case 0x03:
-					Address = (void*)&SerialNumberString;
+					Address = &SerialNumberString;
 					Size    = pgm_read_byte(&SerialNumberString.Header.Size);
 					break;
 				case 0xEE:
 					/* A Microsoft-proprietary extension. String address 0xEE is used by Windows for
 					   "OS Descriptors", which in this case allows us to indicate that our device is
 					   Sideshow compatible regardless of VID/PID values. */
-					Address = (void*)&OSDescriptorString;
+					Address = &OSDescriptorString;
 					Size    = pgm_read_byte(&OSDescriptorString.Header.Size);
 					break;
 			}
@@ -211,7 +211,7 @@ uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue,
 
 uint16_t USB_GetOSFeatureDescriptor(const uint16_t wValue,
                                     const uint8_t wIndex,
-                                    void** const DescriptorAddress)
+                                    const void** const DescriptorAddress)
 {
 	void*    Address = NULL;
 	uint16_t Size    = NO_DESCRIPTOR;
diff --git a/Demos/Device/Incomplete/Sideshow/Descriptors.h b/Demos/Device/Incomplete/Sideshow/Descriptors.h
index f988a48f1..5ba737b38 100644
--- a/Demos/Device/Incomplete/Sideshow/Descriptors.h
+++ b/Demos/Device/Incomplete/Sideshow/Descriptors.h
@@ -87,10 +87,12 @@
 	/* Function Prototypes: */
 		uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue,
 		                                    const uint8_t wIndex,
-		                                    void** const DescriptorAddress) ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(3);
+		                                    const void** const DescriptorAddress)
+		                                    ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(3);
 
 		uint16_t USB_GetOSFeatureDescriptor(const uint16_t wValue,
 		                                    const uint8_t wIndex,
-		                                    void** const DescriptorAddress) ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(3);
+		                                    const void** const DescriptorAddress)
+		                                    ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(3);
 
 #endif
diff --git a/Demos/Device/Incomplete/TestAndMeasurement/Descriptors.c b/Demos/Device/Incomplete/TestAndMeasurement/Descriptors.c
index a56471568..53c6a0193 100644
--- a/Demos/Device/Incomplete/TestAndMeasurement/Descriptors.c
+++ b/Demos/Device/Incomplete/TestAndMeasurement/Descriptors.c
@@ -187,37 +187,37 @@ USB_Descriptor_String_t PROGMEM ProductString =
  */
 uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue,
                                     const uint8_t wIndex,
-                                    void** const DescriptorAddress)
+                                    const void** const DescriptorAddress)
 {
 	const uint8_t  DescriptorType   = (wValue >> 8);
 	const uint8_t  DescriptorNumber = (wValue & 0xFF);
 
-	void*          Address = NULL;
-	uint16_t       Size    = NO_DESCRIPTOR;
+	const void* Address = NULL;
+	uint16_t    Size    = NO_DESCRIPTOR;
 
 	switch (DescriptorType)
 	{
 		case DTYPE_Device:
-			Address = (void*)&DeviceDescriptor;
+			Address = &DeviceDescriptor;
 			Size    = sizeof(USB_Descriptor_Device_t);
 			break;
 		case DTYPE_Configuration: 
-			Address = (void*)&ConfigurationDescriptor;
+			Address = &ConfigurationDescriptor;
 			Size    = sizeof(USB_Descriptor_Configuration_t);
 			break;
 		case DTYPE_String: 
 			switch (DescriptorNumber)
 			{
 				case 0x00: 
-					Address = (void*)&LanguageString;
+					Address = &LanguageString;
 					Size    = pgm_read_byte(&LanguageString.Header.Size);
 					break;
 				case 0x01: 
-					Address = (void*)&ManufacturerString;
+					Address = &ManufacturerString;
 					Size    = pgm_read_byte(&ManufacturerString.Header.Size);
 					break;
 				case 0x02: 
-					Address = (void*)&ProductString;
+					Address = &ProductString;
 					Size    = pgm_read_byte(&ProductString.Header.Size);
 					break;
 			}
diff --git a/Demos/Device/Incomplete/TestAndMeasurement/Descriptors.h b/Demos/Device/Incomplete/TestAndMeasurement/Descriptors.h
index 468a5ea1d..975ca10f7 100644
--- a/Demos/Device/Incomplete/TestAndMeasurement/Descriptors.h
+++ b/Demos/Device/Incomplete/TestAndMeasurement/Descriptors.h
@@ -75,6 +75,7 @@
 	/* Function Prototypes: */

 		uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue,

 		                                    const uint8_t wIndex,

-		                                    void** const DescriptorAddress) ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(3);

+		                                    const void** const DescriptorAddress)

+		                                    ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(3);

 

 #endif