usb: hid: macro for report descriptor

Added macro that generates simple report descriptor for mouse.
This improves the readability of hid-mouse sample.

Signed-off-by: Marcin Szymczyk <[email protected]>

Author: masz-nordic

include/usb/class/usb_hid.h

@@ -168,6 +168,73 @@ struct hid_ops {
 #define HID_PROTOCOL_BOOT		0x00
 #define HID_PROTOCOL_REPORT		0x01
 
+/* Example HID report descriptors */
+/**
+ * @brief Simple HID mouse report descriptor for n button mouse.
+ *
+ * @param bcnt	Button count. Allowed values from 1 to 8.
+ */
+#define HID_MOUSE_REPORT_DESC(bcnt) {				\
+	/* USAGE_PAGE (Generic Desktop) */			\
+	HID_GI_USAGE_PAGE, USAGE_GEN_DESKTOP,			\
+	/* USAGE (Mouse) */					\
+	HID_LI_USAGE, USAGE_GEN_DESKTOP_MOUSE,			\
+	/* COLLECTION (Application) */				\
+	HID_MI_COLLECTION, COLLECTION_APPLICATION,		\
+		/* USAGE (Pointer) */				\
+		HID_LI_USAGE, USAGE_GEN_DESKTOP_POINTER,	\
+		/* COLLECTION (Physical) */			\
+		HID_MI_COLLECTION, COLLECTION_PHYSICAL,		\
+			/* Bits used for button signalling */	\
+			/* USAGE_PAGE (Button) */		\
+			HID_GI_USAGE_PAGE, USAGE_GEN_BUTTON,	\
+			/* USAGE_MINIMUM (Button 1) */		\
+			HID_LI_USAGE_MIN(1), 0x01,		\
+			/* USAGE_MAXIMUM (Button bcnt) */	\
+			HID_LI_USAGE_MAX(1), bcnt,		\
+			/* LOGICAL_MINIMUM (0) */		\
+			HID_GI_LOGICAL_MIN(1), 0x00,		\
+			/* LOGICAL_MAXIMUM (1) */		\
+			HID_GI_LOGICAL_MAX(1), 0x01,		\
+			/* REPORT_SIZE (1) */			\
+			HID_GI_REPORT_SIZE, 0x01,		\
+			/* REPORT_COUNT (bcnt) */		\
+			HID_GI_REPORT_COUNT, bcnt,		\
+			/* INPUT (Data,Var,Abs) */		\
+			HID_MI_INPUT, 0x02,			\
+			/* Unused bits */			\
+			/* REPORT_SIZE (8 - bcnt) */		\
+			HID_GI_REPORT_SIZE, (8 - bcnt),		\
+			/* REPORT_COUNT (1) */			\
+			HID_GI_REPORT_COUNT, 0x01,		\
+			/* INPUT (Cnst,Ary,Abs) */		\
+			HID_MI_INPUT, 0x01,			\
+			/* X and Y axis, scroll */		\
+			/* USAGE_PAGE (Generic Desktop) */	\
+			HID_GI_USAGE_PAGE, USAGE_GEN_DESKTOP,	\
+			/* USAGE (X) */				\
+			HID_LI_USAGE, USAGE_GEN_DESKTOP_X,	\
+			/* USAGE (Y) */				\
+			HID_LI_USAGE, USAGE_GEN_DESKTOP_Y,	\
+			/* USAGE (WHEEL) */			\
+			HID_LI_USAGE, USAGE_GEN_DESKTOP_WHEEL,	\
+			/* LOGICAL_MINIMUM (-127) */		\
+			HID_GI_LOGICAL_MIN(1), -127,		\
+			/* LOGICAL_MAXIMUM (127) */		\
+			HID_GI_LOGICAL_MAX(1), 127,		\
+			/* REPORT_SIZE (8) */			\
+			HID_GI_REPORT_SIZE, 0x08,		\
+			/* REPORT_COUNT (3) */			\
+			HID_GI_REPORT_COUNT, 0x03,		\
+			/* INPUT (Data,Var,Rel) */		\
+			HID_MI_INPUT, 0x06,			\
+		/* END_COLLECTION */				\
+		HID_MI_COLLECTION_END,				\
+	/* END_COLLECTION */					\
+	HID_MI_COLLECTION_END,					\
+}
+
+
 /* Register HID device */
 void usb_hid_register_device(const u8_t *desc, size_t size,
 			     const struct hid_ops *op);

samples/subsys/usb/hid-mouse/src/main.c

@@ -77,62 +77,7 @@ LOG_MODULE_REGISTER(main);
 #define LED_PORT	LED0_GPIO_CONTROLLER
 #define LED		LED0_GPIO_PIN
 
-static const u8_t hid_report_desc[] = {
-	HID_GI_USAGE_PAGE, USAGE_GEN_DESKTOP,
-	/* USAGE_PAGE (Generic Desktop)				05 01 */
-	HID_LI_USAGE, USAGE_GEN_DESKTOP_MOUSE,
-	/* USAGE (Mouse)					09 02 */
-		HID_MI_COLLECTION, COLLECTION_APPLICATION,
-		/* COLLECTION (Application)			A1 01 */
-			HID_LI_USAGE, USAGE_GEN_DESKTOP_POINTER,
-		/* 	USAGE (Pointer)				09 01 */
-			HID_MI_COLLECTION, COLLECTION_PHYSICAL,
-		/* 	COLLECTION (Physical)			A1 00 */
-				HID_GI_USAGE_PAGE, USAGE_GEN_BUTTON,
-		/* 		USAGE_PAGE (Button)		05 09 */
-				HID_LI_USAGE_MIN(1), 0x01,
-		/* 		USAGE_MINIMUM (Button 1)	19 01 */
-				HID_LI_USAGE_MAX(1), 0x03,
-		/* 		USAGE_MAXIMUM (Button 3)	29 03 */
-				HID_GI_LOGICAL_MIN(1), 0,
-		/* 		LOGICAL_MINIMUM (0)		15 00 */
-				HID_GI_LOGICAL_MAX(1), 1,
-		/* 		LOGICAL_MAXIMUM (1)		25 01 */
-				HID_GI_REPORT_COUNT, 3,
-		/* 		REPORT_COUNT (3)		95 03 */
-				HID_GI_REPORT_SIZE, 1,
-		/* 		REPORT_SIZE (1)			75 01 */
-				HID_MI_INPUT, 0x02,
-		/* 		INPUT (Data,Var,Abs)		81 02 */
-				HID_GI_REPORT_COUNT, 1,
-		/* 		REPORT_COUNT (1)		95 01 */
-				HID_GI_REPORT_SIZE, 5,
-		/* 		REPORT_SIZE (5)			75 05 */
-				HID_MI_INPUT, 0x01,
-		/* 		INPUT (Cnst,Ary,Abs)		81 01 */
-				HID_GI_USAGE_PAGE, USAGE_GEN_DESKTOP,
-		/* 		USAGE_PAGE (Generic Desktop)	05 01 */
-				HID_LI_USAGE, USAGE_GEN_DESKTOP_X,
-		/* 		USAGE (X)			09 30 */
-				HID_LI_USAGE, USAGE_GEN_DESKTOP_Y,
-		/* 		USAGE (Y)			09 31 */
-				HID_LI_USAGE, USAGE_GEN_DESKTOP_WHEEL,
-		/* 		USAGE (Wheel)			09 38 */
-				HID_GI_LOGICAL_MIN(1), -127,
-		/* 		LOGICAL_MINIMUM (-127)		15 81 */
-				HID_GI_LOGICAL_MAX(1), 127,
-		/* 		LOGICAL_MAXIMUM (127)		25 7F */
-				HID_GI_REPORT_SIZE, 8,
-		/* 		REPORT_SIZE (8)			75 08 */
-				HID_GI_REPORT_COUNT, 3,
-		/* 		REPORT_COUNT (3)		95 03 */
-				HID_MI_INPUT, 0x06,
-		/* 		INPUT (Data,Var,Rel)		81 06 */
-			HID_MI_COLLECTION_END,
-		/* 	END_COLLECTION				C0    */
-		HID_MI_COLLECTION_END,
-		/* END_COLLECTION				C0    */
-};
+static const u8_t hid_report_desc[] = HID_MOUSE_REPORT_DESC(2);
 
 static u32_t def_val[4];
 static volatile u8_t status[4];