add board_get_unique_id() for serial number

implemented board_get_unique_id() for rp2040 and L4

examples/device/cdc_msc/src/usb_descriptors.c

@@ -23,6 +23,7 @@
  *
  */
 
+#include "bsp/board_api.h"
 #include "tusb.h"
 
 /* A combination of interfaces must have a unique product id, since PC will save device driver after the first plug.
@@ -236,6 +237,14 @@ uint8_t const * tud_descriptor_configuration_cb(uint8_t index)
 // String Descriptors
 //--------------------------------------------------------------------+
 
+// String Descriptor Index
+enum {
+  STRID_LANGID = 0,
+  STRID_MANUFACTURER,
+  STRID_PRODUCT,
+  STRID_SERIAL,
+};
+
 // array of pointer to string descriptors
 char const* string_desc_arr [] =
 {
@@ -247,7 +256,7 @@ char const* string_desc_arr [] =
   "TinyUSB MSC",                 // 5: MSC Interface
 };
 
-static uint16_t _desc_str[32];
+static uint16_t _desc_str[32+1];
 
 // Invoked when received GET STRING DESCRIPTOR request
 // Application return pointer to descriptor, whose contents must exist long enough for transfer to complete
@@ -255,14 +264,19 @@ uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
 {
   (void) langid;
 
-  uint8_t chr_count;
+  size_t chr_count;
 
-  if ( index == 0)
-  {
+  switch(index) {
+    case STRID_LANGID:
       memcpy(&_desc_str[1], string_desc_arr[0], 2);
       chr_count = 1;
-  }else
-  {
+      break;
+
+    case STRID_SERIAL:
+      chr_count = board_usb_get_serial(_desc_str+1, 32);
+      break;
+
+    default:
       // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors.
       // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors
 
@@ -271,14 +285,14 @@ uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
       const char* str = string_desc_arr[index];
 
       // Cap at max char
-    chr_count = (uint8_t) strlen(str);
+      chr_count = strlen(str);
       if ( chr_count > 31 ) chr_count = 31;
 
       // Convert ASCII string into UTF-16
-    for(uint8_t i=0; i<chr_count; i++)
-    {
+      for(size_t i=0; i<chr_count; i++) {
         _desc_str[1+i] = str[i];
       }
+      break;
   }
 
   // first byte is length (including header), second byte is string type

hw/bsp/board_api.h

@@ -60,12 +60,13 @@ void board_led_write(bool state);
 // a '1' means active (pressed), a '0' means inactive.
 uint32_t board_button_read(void);
 
-// Get characters from UART
-// Return number of read bytes
+// Get board unique ID for USB serial number. Return number of bytes. Note max_len is typically 16
+TU_ATTR_WEAK size_t board_get_unique_id(uint8_t id[], size_t max_len);
+
+// Get characters from UART. Return number of read bytes
 int board_uart_read(uint8_t *buf, int len);
 
-// Send characters to UART
-// Return number of sent bytes
+// Send characters to UART. Return number of sent bytes
 int board_uart_write(void const *buf, int len);
 
 #if CFG_TUSB_OS == OPT_OS_NONE
@@ -108,6 +109,37 @@ static inline void board_led_off(void) {
   board_led_write(false);
 }
 
+// Get USB Serial number string from unique ID if available. Return number of character.
+// Input is string descriptor from index 1 (index 0 is type + len)
+static inline size_t board_usb_get_serial(uint16_t desc_str1[], size_t max_chars) {
+  uint8_t serial_id[16] TU_ATTR_ALIGNED(4);
+  size_t serial_len;
+
+  if ( board_get_unique_id ) {
+    serial_len = board_get_unique_id(serial_id, sizeof(serial_id));
+  }else {
+    // fixed serial string is 01234567889ABCDEF
+    *((uint32_t*)(uintptr_t) serial_id) = 0x67452301;
+    *((uint32_t*)(uintptr_t) (serial_id+4)) = 0xEFCDAB89;
+    serial_len = 8;
+  }
+
+  if ( serial_len > max_chars / 2 ) serial_len = max_chars / 2;
+
+  for ( size_t i = 0; i < serial_len; i++ ) {
+    for ( size_t j = 0; j < 2; j++ ) {
+      const char nibble_to_hex[16] = {
+          '0', '1', '2', '3', '4', '5', '6', '7',
+          '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
+      };
+      uint8_t const nibble = (serial_id[i] >> (j * 4)) & 0xf;
+      desc_str1[i * 2 + (1 - j)] = nibble_to_hex[nibble]; // UTF-16-LE
+    }
+  }
+
+  return 2*serial_len;
+}
+
 // TODO remove
 static inline void board_delay(uint32_t ms) {
   uint32_t start_ms = board_millis();

hw/bsp/family_support.cmake

@@ -289,7 +289,8 @@ function(family_add_default_example_warnings TARGET)
     -Wfatal-errors
     -Wdouble-promotion
     -Wfloat-equal
-    -Wshadow
+    # FIXME commented out because of https://github.com/raspberrypi/pico-sdk/issues/1468
+    #-Wshadow
     -Wwrite-strings
     -Wsign-compare
     -Wmissing-format-attribute

hw/bsp/rp2040/family.c

@@ -27,6 +27,7 @@
 
 #include "pico/stdlib.h"
 #include "pico/binary_info.h"
+#include "pico/unique_id.h"
 #include "hardware/gpio.h"
 #include "hardware/sync.h"
 #include "hardware/structs/ioqspi.h"
@@ -171,8 +172,7 @@ void board_init(void)
 // Board porting API
 //--------------------------------------------------------------------+
 
-void board_led_write(bool state)
-{
+void board_led_write(bool state) {
   (void) state;
 
 #ifdef LED_PIN
@@ -180,8 +180,7 @@ void board_led_write(bool state)
 #endif
 }
 
-uint32_t board_button_read(void)
-{
+uint32_t board_button_read(void) {
 #ifdef BUTTON_BOOTSEL
   return BUTTON_STATE_ACTIVE == get_bootsel_button();
 #else
@@ -189,12 +188,21 @@ uint32_t board_button_read(void)
 #endif
 }
 
-int board_uart_read(uint8_t* buf, int len)
-{
+size_t board_get_unique_id(uint8_t id[], size_t max_len) {
+  pico_unique_board_id_t pico_id;
+  pico_get_unique_board_id(&pico_id);
+
+  size_t len = PICO_UNIQUE_BOARD_ID_SIZE_BYTES;
+  if (len > max_len) len = max_len;
+
+  memcpy(id, pico_id.id, len);
+  return len;
+}
+
+int board_uart_read(uint8_t *buf, int len) {
 #ifdef UART_DEV
   int count = 0;
-  while ( (count < len) && uart_is_readable(uart_inst) )
-  {
+  while ( (count < len) && uart_is_readable(uart_inst) ) {
     buf[count] = uart_getc(uart_inst);
     count++;
   }
@@ -205,8 +213,7 @@ int board_uart_read(uint8_t* buf, int len)
 #endif
 }
 
-int board_uart_write(void const * buf, int len)
-{
+int board_uart_write(void const *buf, int len) {
 #ifdef UART_DEV
   char const *bufch = (char const *) buf;
   for ( int i = 0; i < len; i++ ) {
@@ -219,8 +226,7 @@ int board_uart_write(void const * buf, int len)
 #endif
 }
 
-int board_getchar(void)
-{
+int board_getchar(void) {
   return getchar_timeout_us(0);
 }
 

hw/bsp/rp2040/family.cmake

@@ -112,6 +112,7 @@ target_sources(tinyusb_bsp INTERFACE
 target_include_directories(tinyusb_bsp INTERFACE
 	${TOP}/hw
 	)
+target_link_libraries(tinyusb_bsp	INTERFACE pico_unique_id)
 
 # tinyusb_additions will hold our extra settings for examples
 add_library(tinyusb_additions INTERFACE)

hw/bsp/stm32l4/family.c

@@ -48,8 +48,7 @@ void USB_IRQHandler(void)
 
 UART_HandleTypeDef UartHandle;
 
-void board_init(void)
-{
+void board_init(void) {
   board_clock_init();
 
   // Enable All GPIOs clocks
@@ -177,51 +176,60 @@ void board_init(void)
 // Board porting API
 //--------------------------------------------------------------------+
 
-void board_led_write(bool state)
-{
+void board_led_write(bool state) {
   GPIO_PinState pin_state = (GPIO_PinState) (state ? LED_STATE_ON : (1 - LED_STATE_ON));
   HAL_GPIO_WritePin(LED_PORT, LED_PIN, pin_state);
 }
 
-uint32_t board_button_read(void)
-{
+uint32_t board_button_read(void) {
   return BUTTON_STATE_ACTIVE == HAL_GPIO_ReadPin(BUTTON_PORT, BUTTON_PIN);
 }
 
-int board_uart_read(uint8_t* buf, int len)
-{
-  (void) buf; (void) len;
+size_t board_get_unique_id(uint8_t id[], size_t max_len) {
+  (void) max_len;
+  volatile uint32_t * stm32_uuid = (volatile uint32_t *) UID_BASE;
+
+  uint8_t const len = 12;
+  uint32_t* id32 = (uint32_t*) (uintptr_t) id;
+
+  id32[0] = stm32_uuid[0];
+  id32[1] = stm32_uuid[1];
+  id32[2] = stm32_uuid[2];
+
+  return len;
+}
+
+int board_uart_read(uint8_t *buf, int len) {
+  (void) buf;
+  (void) len;
   return 0;
 }
 
-int board_uart_write(void const * buf, int len)
-{
+int board_uart_write(void const *buf, int len) {
   HAL_UART_Transmit(&UartHandle, (uint8_t *) (uintptr_t) buf, len, 0xffff);
   return len;
 }
 
 #if CFG_TUSB_OS == OPT_OS_NONE
 volatile uint32_t system_ticks = 0;
-void SysTick_Handler (void)
-{
+
+void SysTick_Handler(void) {
   HAL_IncTick();
   system_ticks++;
 }
 
-uint32_t board_millis(void)
-{
+uint32_t board_millis(void) {
   return system_ticks;
 }
+
 #endif
 
-void HardFault_Handler (void)
-{
+void HardFault_Handler(void) {
   __asm("BKPT #0\n");
 }
 
 // Required by __libc_init_array in startup code if we are compiling using
 // -nostdlib/-nostartfiles.
-void _init(void)
-{
+void _init(void) {
 
 }