From abf105474529a9831851ea78bcc06d1e5ad4e173 Mon Sep 17 00:00:00 2001
From: hathach <thach@tinyusb.org>
Date: Fri, 31 May 2013 16:31:13 +0700
Subject: [PATCH] refractor & beautify string descriptors

---
 demos/device/keyboard/tusb_descriptors.c | 32 +++++++++++++-----
 demos/device/keyboard/tusb_descriptors.h | 42 +++++++++++++++++++-----
 2 files changed, 58 insertions(+), 16 deletions(-)

diff --git a/demos/device/keyboard/tusb_descriptors.c b/demos/device/keyboard/tusb_descriptors.c
index 1d01c0eb1..527a56730 100644
--- a/demos/device/keyboard/tusb_descriptors.c
+++ b/demos/device/keyboard/tusb_descriptors.c
@@ -381,15 +381,31 @@ const app_descriptor_configuration_t app_tusb_desc_configuration =
 TUSB_CFG_ATTR_USBRAM ATTR_ALIGNED(4)
 const app_descriptor_string_t app_tusb_desc_strings =
 {
-    .LangID = { .bLength = 0x04, .bDescriptorType = TUSB_DESC_TYPE_STRING },
-    .strLangID= {0x0409}, // US English
+    //------------- index 0 -------------//
+    .language = {
+        .bLength         = 0x04,
+        .bDescriptorType = TUSB_DESC_TYPE_STRING,
+        .id              = 0x0409, // US English
+    },
 
-    .Manufacturer = { .bLength = USB_STRING_LEN(sizeof(TUSB_CFG_DEVICE_STRING_MANUFACTURER)-1), .bDescriptorType = TUSB_DESC_TYPE_STRING },
-    .strManufacturer = {'t', 'i', 'n', 'y', 'U', 'S', 'B'},
+    //------------- index 1 -------------//
+    .manufacturer = {
+        .bLength         = USB_STRING_LEN(sizeof(TUSB_CFG_DEVICE_STRING_MANUFACTURER)-1),
+        .bDescriptorType = TUSB_DESC_TYPE_STRING,
+        .unicode_string  = {'t', 'i', 'n', 'y', 'U', 'S', 'B'}
+    },
 
-    .Product = { .bLength = USB_STRING_LEN(sizeof(TUSB_CFG_DEVICE_STRING_PRODUCT)-1), .bDescriptorType = TUSB_DESC_TYPE_STRING },
-    .strProduct = {'D', 'e', 'v', 'i', 'c', 'e', ' ', 'K', 'e', 'y', 'b', 'o', 'a', 'r', 'd'},
+    //------------- index 2 -------------//
+    .product = {
+        .bLength         = USB_STRING_LEN(sizeof(TUSB_CFG_DEVICE_STRING_PRODUCT)-1),
+        .bDescriptorType = TUSB_DESC_TYPE_STRING,
+        .unicode_string  = {'D', 'e', 'v', 'i', 'c', 'e', ' ', 'K', 'e', 'y', 'b', 'o', 'a', 'r', 'd'}
+    },
 
-    .Serial = { .bLength = USB_STRING_LEN(sizeof(TUSB_CFG_DEVICE_STRING_SERIAL)-1), .bDescriptorType = TUSB_DESC_TYPE_STRING },
-    .strSerial = {'1', '2', '3', '4'}
+    //------------- index 3 -------------//
+    .serials = {
+        .bLength         = USB_STRING_LEN(sizeof(TUSB_CFG_DEVICE_STRING_SERIAL)-1),
+        .bDescriptorType = TUSB_DESC_TYPE_STRING,
+        .unicode_string  = {'1', '2', '3', '4'}
+    }
 };
diff --git a/demos/device/keyboard/tusb_descriptors.h b/demos/device/keyboard/tusb_descriptors.h
index 2192fe119..8a9edad84 100644
--- a/demos/device/keyboard/tusb_descriptors.h
+++ b/demos/device/keyboard/tusb_descriptors.h
@@ -48,17 +48,43 @@
 
 typedef ATTR_PACKED_STRUCT(struct)
 {
-  tusb_descriptor_header_t LangID;
-  uint16_t strLangID[1];
+  uint8_t  bLength         ; ///< Size of this descriptor in bytes
+  uint8_t  bDescriptorType ; ///< Descriptor Type
+  uint16_t unicode_string[];
+} tusb_descriptor_string_t;
 
-  tusb_descriptor_header_t Manufacturer;
-  uint16_t strManufacturer[sizeof(TUSB_CFG_DEVICE_STRING_MANUFACTURER)-1]; // exclude null-character
+typedef ATTR_PACKED_STRUCT(struct)
+{
+  //------------- index 0 -------------//
+  struct {
+    uint8_t const bLength;
+    uint8_t const bDescriptorType;
+    uint16_t id;
+  }language;
 
-  tusb_descriptor_header_t Product;
-  uint16_t strProduct[sizeof(TUSB_CFG_DEVICE_STRING_PRODUCT)-1]; // exclude null-character
+  //------------- index 1 -------------//
+  struct {
+    uint8_t const bLength;
+    uint8_t const bDescriptorType;
+    uint16_t unicode_string[sizeof(TUSB_CFG_DEVICE_STRING_MANUFACTURER)-1]; // exclude null-character
+  } manufacturer;
+
+  //------------- index 2 -------------//
+  struct {
+    uint8_t const bLength;
+    uint8_t const bDescriptorType;
+    uint16_t unicode_string[sizeof(TUSB_CFG_DEVICE_STRING_PRODUCT)-1]; // exclude null-character
+  } product;
+
+  //------------- index 3 -------------//
+  struct {
+    uint8_t const bLength;
+    uint8_t const bDescriptorType;
+    uint16_t unicode_string[sizeof(TUSB_CFG_DEVICE_STRING_SERIAL)-1]; // exclude null-character
+  } serials;
+
+  //------------- more string index -------------//
 
-  tusb_descriptor_header_t Serial;
-  uint16_t strSerial[sizeof(TUSB_CFG_DEVICE_STRING_SERIAL)-1];
 } app_descriptor_string_t;
 
 // USB Interface Assosication Descriptor