diff --git a/examples/device/audio_test_multi_rate/src/usb_descriptors.h b/examples/device/audio_test_multi_rate/src/usb_descriptors.h
index c02f40cd9..948a7f4ae 100644
--- a/examples/device/audio_test_multi_rate/src/usb_descriptors.h
+++ b/examples/device/audio_test_multi_rate/src/usb_descriptors.h
@@ -23,8 +23,8 @@
  *
  */
 
-#ifndef _USB_DESCRIPTORS_H_
-#define _USB_DESCRIPTORS_H_
+#ifndef USB_DESCRIPTORS_H_
+#define USB_DESCRIPTORS_H_
 
 // #include "tusb.h"
 
diff --git a/examples/device/cdc_msc/src/main.c b/examples/device/cdc_msc/src/main.c
index 5d70903bc..ff998a13d 100644
--- a/examples/device/cdc_msc/src/main.c
+++ b/examples/device/cdc_msc/src/main.c
@@ -123,7 +123,7 @@ void cdc_task(void) {
     static uint32_t btn_prev = 0;
     static cdc_notify_uart_state_t uart_state = { .value = 0 };
     const uint32_t btn = board_button_read();
-    if ((btn_prev == 0) && btn) {
+    if ((btn_prev == 0u) && btn) {
       uart_state.dsr ^= 1;
       tud_cdc_notify_uart_state(&uart_state);
     }
diff --git a/examples/device/cdc_uac2/src/cdc_app.c b/examples/device/cdc_uac2/src/cdc_app.c
index 2166c1d6b..e3ad8a9ac 100644
--- a/examples/device/cdc_uac2/src/cdc_app.c
+++ b/examples/device/cdc_uac2/src/cdc_app.c
@@ -29,33 +29,26 @@
 #include "common.h"
 
 // Invoked when cdc when line state changed e.g connected/disconnected
-void tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts)
-{
+void tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts) {
   (void) itf;
   (void) rts;
 
-  if (dtr)
-  {
+  if (dtr) {
     // Terminal connected
-  }
-  else
-  {
+  } else {
     // Terminal disconnected
   }
 }
 
 // Invoked when CDC interface received data from host
-void tud_cdc_rx_cb(uint8_t itf)
-{
+void tud_cdc_rx_cb(uint8_t itf) {
   uint8_t buf[64];
   uint32_t count;
 
   // connected() check for DTR bit
   // Most but not all terminal client set this when making connection
-  if (tud_cdc_connected())
-  {
-    if (tud_cdc_available()) // data is available
-    {
+  if (tud_cdc_connected()) {
+    if (tud_cdc_available()) {
       count = tud_cdc_n_read(itf, buf, sizeof(buf));
       (void) count;
 
diff --git a/examples/device/cdc_uac2/src/usb_descriptors.h b/examples/device/cdc_uac2/src/usb_descriptors.h
index 95d8da5c3..139384d3e 100644
--- a/examples/device/cdc_uac2/src/usb_descriptors.h
+++ b/examples/device/cdc_uac2/src/usb_descriptors.h
@@ -24,8 +24,8 @@
  *
  */
 
-#ifndef _USB_DESCRIPTORS_H_
-#define _USB_DESCRIPTORS_H_
+#ifndef USB_DESCRIPTORS_H_
+#define USB_DESCRIPTORS_H_
 
 // #include "tusb.h"
 
diff --git a/examples/device/net_lwip_webserver/src/lwipopts.h b/examples/device/net_lwip_webserver/src/lwipopts.h
index 04949cef9..11686ce2a 100644
--- a/examples/device/net_lwip_webserver/src/lwipopts.h
+++ b/examples/device/net_lwip_webserver/src/lwipopts.h
@@ -29,8 +29,8 @@
  * Author: Simon Goldschmidt
  *
  */
-#ifndef __LWIPOPTS_H__
-#define __LWIPOPTS_H__
+#ifndef LWIPOPTS_H__
+#define LWIPOPTS_H__
 
 /* Prevent having to link sys_arch.c (we don't test the API layers in unit tests) */
 #define NO_SYS                          1
diff --git a/examples/device/uac2_headset/src/usb_descriptors.h b/examples/device/uac2_headset/src/usb_descriptors.h
index d673beace..47154626e 100644
--- a/examples/device/uac2_headset/src/usb_descriptors.h
+++ b/examples/device/uac2_headset/src/usb_descriptors.h
@@ -23,8 +23,8 @@
  *
  */
 
-#ifndef _USB_DESCRIPTORS_H_
-#define _USB_DESCRIPTORS_H_
+#ifndef USB_DESCRIPTORS_H_
+#define USB_DESCRIPTORS_H_
 
 enum
 {
diff --git a/examples/device/uac2_speaker_fb/src/usb_descriptors.h b/examples/device/uac2_speaker_fb/src/usb_descriptors.h
index b0ec60ea1..79f25bbfa 100644
--- a/examples/device/uac2_speaker_fb/src/usb_descriptors.h
+++ b/examples/device/uac2_speaker_fb/src/usb_descriptors.h
@@ -23,8 +23,8 @@
  *
  */
 
-#ifndef _USB_DESCRIPTORS_H_
-#define _USB_DESCRIPTORS_H_
+#ifndef USB_DESCRIPTORS_H_
+#define USB_DESCRIPTORS_H_
 
 //--------------------------------------------------------------------+
 // UAC2 DESCRIPTOR TEMPLATES
diff --git a/examples/host/cdc_msc_hid_freertos/src/cdc_app.c b/examples/host/cdc_msc_hid_freertos/src/cdc_app.c
index 279efe7b7..0e0105980 100644
--- a/examples/host/cdc_msc_hid_freertos/src/cdc_app.c
+++ b/examples/host/cdc_msc_hid_freertos/src/cdc_app.c
@@ -46,9 +46,9 @@ static void cdc_app_task(void* param);
 
 void cdc_app_init(void) {
   #if configSUPPORT_STATIC_ALLOCATION
-  xTaskCreateStatic(cdc_app_task, "cdc", CDC_STACK_SZIE, NULL, configMAX_PRIORITIES-2, cdc_stack, &cdc_taskdef);
+  (void) xTaskCreateStatic(cdc_app_task, "cdc", CDC_STACK_SZIE, NULL, configMAX_PRIORITIES-2, cdc_stack, &cdc_taskdef);
   #else
-  xTaskCreate(cdc_app_task, "cdc", CDC_STACK_SZIE, NULL, configMAX_PRIORITIES-2, NULL);
+  (void) xTaskCreate(cdc_app_task, "cdc", CDC_STACK_SZIE, NULL, configMAX_PRIORITIES-2, NULL);
   #endif
 }
 
@@ -57,7 +57,9 @@ static size_t get_console_inputs(uint8_t *buf, size_t bufsize) {
   size_t count = 0;
   while (count < bufsize) {
     int ch = board_getchar();
-    if (ch <= 0) break;
+    if (ch <= 0) {
+      break;
+    }
 
     buf[count] = (uint8_t) ch;
     count++;
diff --git a/hw/bsp/board.c b/hw/bsp/board.c
index 476ec6733..483d9dc28 100644
--- a/hw/bsp/board.c
+++ b/hw/bsp/board.c
@@ -51,8 +51,7 @@ int sys_read(int fhdl, char *buf, size_t count) TU_ATTR_USED;
 
 int sys_write(int fhdl, const char *buf, size_t count) {
   (void) fhdl;
-  SEGGER_RTT_Write(0, buf, (int) count);
-  return (int) count;
+  return (int) SEGGER_RTT_Write(0, buf, (int) count);
 }
 
 int sys_read(int fhdl, char *buf, size_t count) {
@@ -159,7 +158,7 @@ int board_getchar(void) {
 }
 
 void board_putchar(int c) {
-  sys_write(0, (const char*)&c, 1);
+  (void) sys_write(0, (const char*)&c, 1);
 }
 
 uint32_t tusb_time_millis_api(void) {
diff --git a/hw/bsp/board_api.h b/hw/bsp/board_api.h
index 088c5fec4..606ac484f 100644
--- a/hw/bsp/board_api.h
+++ b/hw/bsp/board_api.h
@@ -165,7 +165,7 @@ static inline size_t board_usb_get_serial(uint16_t desc_str1[], size_t max_chars
           '0', '1', '2', '3', '4', '5', '6', '7',
           '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
       };
-      const uint8_t nibble = (uint8_t) ((uid[i] >> (j * 4)) & 0xf);
+      const uint8_t nibble = (uint8_t) ((uid[i] >> (j * 4u)) & 0xfu);
       desc_str1[i * 2 + (1 - j)] = nibble_to_hex[nibble]; // UTF-16-LE
     }
   }
diff --git a/src/class/cdc/cdc.h b/src/class/cdc/cdc.h
index 6d207c717..679723ba6 100644
--- a/src/class/cdc/cdc.h
+++ b/src/class/cdc/cdc.h
@@ -192,10 +192,10 @@ typedef enum {
   CDC_LINE_CODING_STOP_BITS_2   = 2, // 2   bits
 } cdc_line_coding_stopbits_t;
 
-#define CDC_LINE_CODING_STOP_BITS_TEXT(STOP_BITS) (        \
-  STOP_BITS == CDC_LINE_CODING_STOP_BITS_1 ?   "1" :       \
-  STOP_BITS == CDC_LINE_CODING_STOP_BITS_1_5 ? "1.5" :     \
-  STOP_BITS == CDC_LINE_CODING_STOP_BITS_2 ?   "2"   : "?" )
+#define CDC_LINE_CODING_STOP_BITS_TEXT(STOP_BITS) (          \
+  (STOP_BITS) == CDC_LINE_CODING_STOP_BITS_1   ? "1" :       \
+  (STOP_BITS) == CDC_LINE_CODING_STOP_BITS_1_5 ? "1.5" :     \
+  (STOP_BITS) == CDC_LINE_CODING_STOP_BITS_2   ? "2"   : "?" )
 
 // TODO Backward compatible for typos. Maybe removed in the future release
 #define CDC_LINE_CONDING_STOP_BITS_1   CDC_LINE_CODING_STOP_BITS_1
@@ -211,11 +211,11 @@ typedef enum {
 } cdc_line_coding_parity_t;
 
 #define CDC_LINE_CODING_PARITY_CHAR(PARITY) (        \
-  PARITY == CDC_LINE_CODING_PARITY_NONE  ? 'N' :     \
-  PARITY == CDC_LINE_CODING_PARITY_ODD   ? 'O' :     \
-  PARITY == CDC_LINE_CODING_PARITY_EVEN  ? 'E' :     \
-  PARITY == CDC_LINE_CODING_PARITY_MARK  ? 'M' :     \
-  PARITY == CDC_LINE_CODING_PARITY_SPACE ? 'S' : '?' )
+  (PARITY) == CDC_LINE_CODING_PARITY_NONE  ? 'N' :     \
+  (PARITY) == CDC_LINE_CODING_PARITY_ODD   ? 'O' :     \
+  (PARITY) == CDC_LINE_CODING_PARITY_EVEN  ? 'E' :     \
+  (PARITY) == CDC_LINE_CODING_PARITY_MARK  ? 'M' :     \
+  (PARITY) == CDC_LINE_CODING_PARITY_SPACE ? 'S' : '?' )
 
 //--------------------------------------------------------------------+
 // Management Element Notification (Notification Endpoint)
diff --git a/src/class/video/video_device.c b/src/class/video/video_device.c
index 087292e56..14eba86fb 100644
--- a/src/class/video/video_device.c
+++ b/src/class/video/video_device.c
@@ -464,7 +464,9 @@ static bool _update_streaming_parameters(videod_streaming_interface_t const *stm
   uint_fast8_t fmtnum = param->bFormatIndex;
   TU_ASSERT(vs && fmtnum <= vs->stm.bNumFormats);
   if (0 == fmtnum) {
-    if (1 < vs->stm.bNumFormats) return true; /* Need to negotiate all variables. */
+    if (1 < vs->stm.bNumFormats) {
+      return true; /* Need to negotiate all variables. */
+    }
     fmtnum = 1;
     param->bFormatIndex = 1;
   }
@@ -1259,7 +1261,7 @@ bool tud_video_n_frame_xfer(uint_fast8_t ctl_idx, uint_fast8_t stm_idx, void *bu
   videod_streaming_interface_t *stm = _get_instance_streaming(ctl_idx, stm_idx);
   videod_streaming_epbuf_t *stm_epbuf = &_videod_streaming_epbuf[ctl_idx];
 
-  if ( NULL == stm || 0 == stm->desc.ep[0] || stm->buffer) {
+  if (NULL == stm || 0 == stm->desc.ep[0] || stm->buffer) {
     return false;
   }
   if (stm->state == VS_STATE_PROBING) {
diff --git a/src/common/tusb_common.h b/src/common/tusb_common.h
index ac1c6457f..5f659eb95 100644
--- a/src/common/tusb_common.h
+++ b/src/common/tusb_common.h
@@ -111,7 +111,7 @@ extern void* tusb_app_phys_to_virt(void *phys_addr);
 //--------------------------------------------------------------------+
 
 //------------- Mem -------------//
-#define tu_memclr(buffer, size)  memset((buffer), 0, (size))
+#define tu_memclr(buffer, size)  (void) memset((buffer), 0, (size))
 #define tu_varclr(_var)          tu_memclr(_var, sizeof(*(_var)))
 
 // This is a backport of memset_s from c11
@@ -121,6 +121,10 @@ TU_ATTR_ALWAYS_INLINE static inline int tu_memset_s(void *dest, size_t destsz, i
     return -1;
   }
 
+  if (count == 0u) {
+    return 0;
+  }
+
   if (count > destsz) {
     return -1;
   }
@@ -131,13 +135,15 @@ TU_ATTR_ALWAYS_INLINE static inline int tu_memset_s(void *dest, size_t destsz, i
 
 // This is a backport of memcpy_s from c11
 TU_ATTR_ALWAYS_INLINE static inline int tu_memcpy_s(void *dest, size_t destsz, const void *src, size_t count) {
-  // Validate parameters
   if (dest == NULL) {
     return -1;
   }
 
-  // For memcpy, src may be NULL only if count == 0. Reject otherwise.
-  if (src == NULL && count != 0u) {
+  if (count == 0u) {
+    return 0;
+  }
+
+  if (src == NULL) {
     return -1;
   }
 
@@ -230,7 +236,7 @@ TU_ATTR_ALWAYS_INLINE static inline uint32_t tu_round_up(uint32_t v, uint32_t f)
 // TODO use clz TODO remove
 TU_ATTR_ALWAYS_INLINE static inline uint8_t tu_log2(uint32_t value) {
   uint8_t result = 0;
-  while ((value >>= 1) != 0) {
+  while (value >>= 1) {
     result++;
   }
   return result;
diff --git a/src/common/tusb_compiler.h b/src/common/tusb_compiler.h
index 49421e865..167385d13 100644
--- a/src/common/tusb_compiler.h
+++ b/src/common/tusb_compiler.h
@@ -77,19 +77,19 @@
 /*------------------------------------------------------------------*/
 /* Count number of arguments of __VA_ARGS__
  * - reference www.stackoverflow.com/questions/2124339/c-preprocessor-va-args-number-of-arguments
- * - _GET_NTH_ARG() takes args >= N (64) but only expand to Nth one (64th)
- * - _RSEQ_N() is reverse sequential to N to add padding to have
+ * - TU_GET_NTH_ARG() takes args >= N (64) but only expand to Nth one (64th)
+ * - TU_NARG_RSEQ_N() is reverse sequential to N to add padding to have
  * Nth position is the same as the number of arguments
  * - ##__VA_ARGS__ is used to deal with 0 paramerter (swallows comma)
  *------------------------------------------------------------------*/
-#if !defined(__CCRX__)
-#define TU_ARGS_NUM(...)   _TU_NARG(_0, ##__VA_ARGS__, _RSEQ_N())
+#if defined(__CCRX__)
+#define TU_ARGS_NUM(...)   TU_NARG_IMPL(_0, __VA_ARGS__, TU_NARG_RSEQ_N())
 #else
-#define TU_ARGS_NUM(...)   _TU_NARG(_0, __VA_ARGS__, _RSEQ_N())
+#define TU_ARGS_NUM(...)   TU_NARG_IMPL(_0, ##__VA_ARGS__, TU_NARG_RSEQ_N())
 #endif
 
-#define _TU_NARG(...)      _GET_NTH_ARG(__VA_ARGS__)
-#define _GET_NTH_ARG( \
+#define TU_NARG_IMPL(...)      TU_GET_NTH_ARG(__VA_ARGS__)
+#define TU_GET_NTH_ARG( \
           _1, _2, _3, _4, _5, _6, _7, _8, _9,_10, \
          _11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \
          _21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \
@@ -97,7 +97,7 @@
          _41,_42,_43,_44,_45,_46,_47,_48,_49,_50, \
          _51,_52,_53,_54,_55,_56,_57,_58,_59,_60, \
          _61,_62,_63,N,...) N
-#define _RSEQ_N() \
+#define TU_NARG_RSEQ_N() \
          62,61,60,                      \
          59,58,57,56,55,54,53,52,51,50, \
          49,48,47,46,45,44,43,42,41,40, \
diff --git a/src/common/tusb_fifo.c b/src/common/tusb_fifo.c
index f7679556f..3b8920c01 100644
--- a/src/common/tusb_fifo.c
+++ b/src/common/tusb_fifo.c
@@ -38,14 +38,16 @@
 
 #if OSAL_MUTEX_REQUIRED
 
-TU_ATTR_ALWAYS_INLINE static inline void _ff_lock(osal_mutex_t mutex)
-{
-  if (mutex) osal_mutex_lock(mutex, OSAL_TIMEOUT_WAIT_FOREVER);
+TU_ATTR_ALWAYS_INLINE static inline void _ff_lock(osal_mutex_t mutex) {
+  if (mutex) {
+    osal_mutex_lock(mutex, OSAL_TIMEOUT_WAIT_FOREVER);
+  }
 }
 
-TU_ATTR_ALWAYS_INLINE static inline void _ff_unlock(osal_mutex_t mutex)
-{
-  if (mutex) osal_mutex_unlock(mutex);
+TU_ATTR_ALWAYS_INLINE static inline void _ff_unlock(osal_mutex_t mutex) {
+  if (mutex) {
+    osal_mutex_unlock(mutex);
+  }
 }
 
 #else
@@ -59,8 +61,7 @@ TU_ATTR_ALWAYS_INLINE static inline void _ff_unlock(osal_mutex_t mutex)
  * \brief Write modes intended to allow special read and write functions to be able to
  *        copy data to and from USB hardware FIFOs as needed for e.g. STM32s and others
  */
-typedef enum
-{
+typedef enum {
   TU_FIFO_COPY_INC,            ///< Copy from/to an increasing source/destination address - default mode
 #ifdef TUP_MEM_CONST_ADDR
   TU_FIFO_COPY_CST_FULL_WORDS, ///< Copy from/to a constant source/destination address - required for e.g. STM32 to write into USB hardware FIFO
@@ -72,7 +73,9 @@ bool tu_fifo_config(tu_fifo_t *f, void* buffer, uint16_t depth, uint16_t item_si
   // Limit index space to 2*depth - this allows for a fast "modulo" calculation
   // but limits the maximum depth to 2^16/2 = 2^15 and buffer overflows are detectable
   // only if overflow happens once (important for unsupervised DMA applications)
-  if (depth > 0x8000) return false;
+  if (depth > 0x8000) {
+    return false;
+  }
 
   _ff_lock(f->mutex_wr);
   _ff_lock(f->mutex_rd);
@@ -98,22 +101,19 @@ bool tu_fifo_config(tu_fifo_t *f, void* buffer, uint16_t depth, uint16_t item_si
 // Intended to be used to read from hardware USB FIFO in e.g. STM32 where all data is read from a constant address
 // Code adapted from dcd_synopsys.c
 // TODO generalize with configurable 1 byte or 4 byte each read
-static void _ff_push_const_addr(uint8_t * ff_buf, const void * app_buf, uint16_t len)
-{
+static void _ff_push_const_addr(uint8_t * ff_buf, const void * app_buf, uint16_t len) {
   volatile const uint32_t * reg_rx = (volatile const uint32_t *) app_buf;
 
   // Reading full available 32 bit words from const app address
   uint16_t full_words = len >> 2;
-  while(full_words--)
-  {
+  while(full_words--) {
     tu_unaligned_write32(ff_buf, *reg_rx);
     ff_buf += 4;
   }
 
   // Read the remaining 1-3 bytes from const app address
   uint8_t const bytes_rem = len & 0x03;
-  if ( bytes_rem )
-  {
+  if (bytes_rem) {
     uint32_t tmp32 = *reg_rx;
     memcpy(ff_buf, &tmp32, bytes_rem);
   }
@@ -121,22 +121,19 @@ static void _ff_push_const_addr(uint8_t * ff_buf, const void * app_buf, uint16_t
 
 // Intended to be used to write to hardware USB FIFO in e.g. STM32
 // where all data is written to a constant address in full word copies
-static void _ff_pull_const_addr(void * app_buf, const uint8_t * ff_buf, uint16_t len)
-{
+static void _ff_pull_const_addr(void * app_buf, const uint8_t * ff_buf, uint16_t len) {
   volatile uint32_t * reg_tx = (volatile uint32_t *) app_buf;
 
   // Write full available 32 bit words to const address
   uint16_t full_words = len >> 2;
-  while(full_words--)
-  {
+  while(full_words--) {
     *reg_tx = tu_unaligned_read32(ff_buf);
     ff_buf += 4;
   }
 
   // Write the remaining 1-3 bytes into const address
   uint8_t const bytes_rem = len & 0x03;
-  if ( bytes_rem )
-  {
+  if (bytes_rem) {
     uint32_t tmp32 = 0;
     memcpy(&tmp32, ff_buf, bytes_rem);
 
@@ -146,8 +143,7 @@ static void _ff_pull_const_addr(void * app_buf, const uint8_t * ff_buf, uint16_t
 #endif
 
 // send one item to fifo WITHOUT updating write pointer
-static inline void _ff_push(tu_fifo_t* f, void const * app_buf, uint16_t rel)
-{
+static inline void _ff_push(tu_fifo_t* f, void const * app_buf, uint16_t rel) {
   memcpy(f->buffer + (rel * f->item_size), app_buf, f->item_size);
 }
 
diff --git a/src/common/tusb_private.h b/src/common/tusb_private.h
index 31aca8a31..37d5e89f1 100644
--- a/src/common/tusb_private.h
+++ b/src/common/tusb_private.h
@@ -141,7 +141,7 @@ uint32_t tu_edpt_stream_read_xfer(uint8_t hwid, tu_edpt_stream_t* s);
 // Complete read transfer by writing EP -> FIFO. Must be called in the transfer complete callback
 TU_ATTR_ALWAYS_INLINE static inline
 void tu_edpt_stream_read_xfer_complete(tu_edpt_stream_t* s, uint32_t xferred_bytes) {
-  if (tu_fifo_depth(&s->ff)) {
+  if (0 != tu_fifo_depth(&s->ff)) {
     tu_fifo_write_n(&s->ff, s->ep_buf, (uint16_t) xferred_bytes);
   }
 }
@@ -149,7 +149,7 @@ void tu_edpt_stream_read_xfer_complete(tu_edpt_stream_t* s, uint32_t xferred_byt
 // Complete read transfer with provided buffer
 TU_ATTR_ALWAYS_INLINE static inline
 void tu_edpt_stream_read_xfer_complete_with_buf(tu_edpt_stream_t* s, const void * buf, uint32_t xferred_bytes) {
-  if (tu_fifo_depth(&s->ff)) {
+  if (0 != tu_fifo_depth(&s->ff)) {
     tu_fifo_write_n(&s->ff, buf, (uint16_t) xferred_bytes);
   }
 }
diff --git a/src/common/tusb_types.h b/src/common/tusb_types.h
index 9197381cf..a3a660d3b 100644
--- a/src/common/tusb_types.h
+++ b/src/common/tusb_types.h
@@ -548,7 +548,7 @@ TU_ATTR_ALWAYS_INLINE static inline uint8_t tu_edpt_number(uint8_t addr) {
 }
 
 TU_ATTR_ALWAYS_INLINE static inline uint8_t tu_edpt_addr(uint8_t num, uint8_t dir) {
-  return (uint8_t) (num | (dir ? TUSB_DIR_IN_MASK : 0));
+  return (uint8_t) (num | (dir == TUSB_DIR_IN ? TUSB_DIR_IN_MASK : 0u));
 }
 
 TU_ATTR_ALWAYS_INLINE static inline uint16_t tu_edpt_packet_size(tusb_desc_endpoint_t const* desc_ep) {
diff --git a/src/common/tusb_verify.h b/src/common/tusb_verify.h
index d6806d44a..ffd785384 100644
--- a/src/common/tusb_verify.h
+++ b/src/common/tusb_verify.h
@@ -78,7 +78,7 @@
     defined(__ARM7M__) || defined (__ARM7EM__) || defined(__ARM8M_MAINLINE__) || defined(__ARM8EM_MAINLINE__)
   #define TU_BREAKPOINT() do {                                                                              \
     volatile uint32_t* ARM_CM_DHCSR =  ((volatile uint32_t*) 0xE000EDF0UL); /* Cortex M CoreDebug->DHCSR */ \
-    if (0 != ((*ARM_CM_DHCSR) & 1UL)) {__asm("BKPT #0\n");} /* Only halt mcu if debugger is attached */            \
+    if (0 != ((*ARM_CM_DHCSR) & 1UL)) { __asm("BKPT #0\n"); } /* Only halt mcu if debugger is attached */   \
   } while(0)
 
 #elif defined(__riscv) && !TUSB_MCU_VENDOR_ESPRESSIF
@@ -98,7 +98,7 @@
  *------------------------------------------------------------------*/
 #define TU_VERIFY_DEFINE(_cond, _ret)    \
   do {                                   \
-    if ( !(_cond) ) { return _ret; }     \
+    if (!(_cond)) { return _ret; }     \
   } while(0)
 
 #define TU_VERIFY_1ARGS(_cond)         TU_VERIFY_DEFINE(_cond, false)
diff --git a/src/device/dcd.h b/src/device/dcd.h
index 436c4555f..1b0289280 100644
--- a/src/device/dcd.h
+++ b/src/device/dcd.h
@@ -214,7 +214,7 @@ TU_ATTR_ALWAYS_INLINE static inline void dcd_event_setup_received(uint8_t rhport
   dcd_event_t event;
   event.rhport = rhport;
   event.event_id = DCD_EVENT_SETUP_RECEIVED;
-  memcpy(&event.setup_received, setup, sizeof(tusb_control_request_t));
+  (void) memcpy(&event.setup_received, setup, sizeof(tusb_control_request_t));
   dcd_event_handler(&event, in_isr);
 }
 
diff --git a/src/device/usbd.c b/src/device/usbd.c
index 05fc752af..9d0bc0f3f 100644
--- a/src/device/usbd.c
+++ b/src/device/usbd.c
@@ -354,6 +354,8 @@ TU_ATTR_ALWAYS_INLINE static inline usbd_class_driver_t const * get_driver(uint8
     driver = &_app_driver[drvid];
   } else if (drvid < TOTAL_DRIVER_COUNT && BUILTIN_DRIVER_COUNT > 0) {
     driver = &_usbd_driver[drvid - _app_driver_count];
+  } else {
+    // nothing to do
   }
   return driver;
 }
@@ -572,7 +574,7 @@ bool tud_deinit(uint8_t rhport) {
   // Deinit device controller driver
   dcd_int_disable(rhport);
   dcd_disconnect(rhport);
-  dcd_deinit(rhport);
+  TU_VERIFY(dcd_deinit(rhport));
 
   // Deinit class drivers
   for (uint8_t i = 0; i < TOTAL_DRIVER_COUNT; i++) {
@@ -594,7 +596,6 @@ bool tud_deinit(uint8_t rhport) {
 #endif
 
   _usbd_rhport = RHPORT_INVALID;
-
   return true;
 }
 
@@ -606,8 +607,8 @@ static void configuration_reset(uint8_t rhport) {
   }
 
   tu_varclr(&_usbd_dev);
-  memset(_usbd_dev.itf2drv, DRVID_INVALID, sizeof(_usbd_dev.itf2drv)); // invalid mapping
-  memset(_usbd_dev.ep2drv, DRVID_INVALID, sizeof(_usbd_dev.ep2drv)); // invalid mapping
+  (void) memset(_usbd_dev.itf2drv, DRVID_INVALID, sizeof(_usbd_dev.itf2drv)); // invalid mapping
+  (void) memset(_usbd_dev.ep2drv, DRVID_INVALID, sizeof(_usbd_dev.ep2drv)); // invalid mapping
 }
 
 static void usbd_reset(uint8_t rhport) {
@@ -638,12 +639,16 @@ void tud_task_ext(uint32_t timeout_ms, bool in_isr) {
   (void) in_isr; // not implemented yet
 
   // Skip if stack is not initialized
-  if (!tud_inited()) return;
+  if (!tud_inited()) {
+    return;
+  }
 
   // Loop until there is no more events in the queue
   while (1) {
     dcd_event_t event;
-    if (!osal_queue_receive(_usbd_q, &event, timeout_ms)) return;
+    if (!osal_queue_receive(_usbd_q, &event, timeout_ms)) {
+      return;
+    }
 
 #if CFG_TUSB_DEBUG >= CFG_TUD_LOG_LEVEL
     if (event.event_id == DCD_EVENT_SETUP_RECEIVED) TU_LOG_USBD("\r\n"); // extra line for setup
@@ -667,7 +672,7 @@ void tud_task_ext(uint32_t timeout_ms, bool in_isr) {
         TU_ASSERT(_usbd_queued_setup > 0,);
         _usbd_queued_setup--;
         TU_LOG_BUF(CFG_TUD_LOG_LEVEL, &event.setup_received, 8);
-        if (_usbd_queued_setup) {
+        if (_usbd_queued_setup != 0) {
           TU_LOG_USBD("  Skipped since there is other SETUP in queue\r\n");
           break;
         }
@@ -703,8 +708,7 @@ void tud_task_ext(uint32_t timeout_ms, bool in_isr) {
         _usbd_dev.ep_status[epnum][ep_dir].claimed = 0;
 
         if (0 == epnum) {
-          usbd_control_xfer_cb(event.rhport, ep_addr, (xfer_result_t) event.xfer_complete.result,
-                               event.xfer_complete.len);
+          usbd_control_xfer_cb(event.rhport, ep_addr, (xfer_result_t) event.xfer_complete.result, event.xfer_complete.len);
         } else {
           usbd_class_driver_t const* driver = get_driver(_usbd_dev.ep2drv[epnum][ep_dir]);
           TU_ASSERT(driver,);
@@ -738,7 +742,7 @@ void tud_task_ext(uint32_t timeout_ms, bool in_isr) {
 
       case USBD_EVENT_FUNC_CALL:
         TU_LOG_USBD("\r\n");
-        if (event.func_call.func) {
+        if (event.func_call.func != NULL) {
           event.func_call.func(event.func_call.param);
         }
         break;
@@ -792,7 +796,7 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
   }
 #endif
 
-  switch ( p_request->bmRequestType_bit.recipient ) {
+  switch (p_request->bmRequestType_bit.recipient) { //-V2520
     //------------- Device Requests e.g in enumeration -------------//
     case TUSB_REQ_RCPT_DEVICE:
       if ( TUSB_REQ_TYPE_CLASS == p_request->bmRequestType_bit.type ) {
@@ -806,13 +810,13 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
         return invoke_class_control(rhport, driver, p_request);
       }
 
-      if ( TUSB_REQ_TYPE_STANDARD != p_request->bmRequestType_bit.type ) {
+      if (TUSB_REQ_TYPE_STANDARD != p_request->bmRequestType_bit.type) {
         // Non-standard request is not supported
         TU_BREAKPOINT();
         return false;
       }
 
-      switch ( p_request->bRequest ) {
+      switch (p_request->bRequest) { //-V2520
         case TUSB_REQ_SET_ADDRESS:
           // Depending on mcu, status phase could be sent either before or after changing device address,
           // or even require stack to not response with status at all
@@ -834,18 +838,15 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
 
           // Only process if new configure is different
           if (_usbd_dev.cfg_num != cfg_num) {
-            if ( _usbd_dev.cfg_num ) {
+            if (_usbd_dev.cfg_num != 0) {
               // already configured: need to clear all endpoints and driver first
               TU_LOG_USBD("  Clear current Configuration (%u) before switching\r\n", _usbd_dev.cfg_num);
 
-              // disable SOF
               dcd_sof_enable(rhport, false);
-
-              // close all non-control endpoints, cancel all pending transfers if any
               dcd_edpt_close_all(rhport);
 
               // close all drivers and current configured state except bus speed
-              uint8_t const speed = _usbd_dev.speed;
+              const uint8_t speed = _usbd_dev.speed;
               configuration_reset(rhport);
 
               _usbd_dev.speed = speed; // restore speed
@@ -853,18 +854,15 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
 
             _usbd_dev.cfg_num = cfg_num;
 
-            // Handle the new configuration and execute the corresponding callback
-            if ( cfg_num ) {
-              // switch to new configuration if not zero
+            // Handle the new configuration
+            if (cfg_num == 0) {
+              tud_umount_cb();
+            } else {
               if (!process_set_config(rhport, cfg_num)) {
-                TU_MESS_FAILED();
-                TU_BREAKPOINT();
                 _usbd_dev.cfg_num = 0;
-                return false;
+                TU_ASSERT(false);
               }
               tud_mount_cb();
-            } else {
-              tud_umount_cb();
             }
           }
 
@@ -873,17 +871,17 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
         break;
 
         case TUSB_REQ_GET_DESCRIPTOR:
-          TU_VERIFY( process_get_descriptor(rhport, p_request) );
+          TU_VERIFY(process_get_descriptor(rhport, p_request));
         break;
 
         case TUSB_REQ_SET_FEATURE:
-          switch(p_request->wValue) {
+          switch(p_request->wValue) { //-V2520
             case TUSB_REQ_FEATURE_REMOTE_WAKEUP:
               TU_LOG_USBD("    Enable Remote Wakeup\r\n");
               // Host may enable remote wake up before suspending especially HID device
               _usbd_dev.remote_wakeup_en = true;
               tud_control_status(rhport, p_request);
-            break;
+              break;
 
             #if CFG_TUD_TEST_MODE
             case TUSB_REQ_FEATURE_TEST_MODE: {
@@ -897,7 +895,7 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
               tud_control_status(rhport, p_request);
               break;
             }
-            #endif /* CFG_TUD_TEST_MODE */
+            #endif
 
             // Stall unsupported feature selector
             default: return false;
@@ -907,13 +905,12 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
         case TUSB_REQ_CLEAR_FEATURE:
           // Only support remote wakeup for device feature
           TU_VERIFY(TUSB_REQ_FEATURE_REMOTE_WAKEUP == p_request->wValue);
-
           TU_LOG_USBD("    Disable Remote Wakeup\r\n");
 
           // Host may disable remote wake up after resuming
           _usbd_dev.remote_wakeup_en = false;
           tud_control_status(rhport, p_request);
-        break;
+          break;
 
         case TUSB_REQ_GET_STATUS: {
           // Device status bit mask
@@ -939,24 +936,24 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
 
       // all requests to Interface (STD or Class) is forwarded to class driver.
       // notable requests are: GET HID REPORT DESCRIPTOR, SET_INTERFACE, GET_INTERFACE
-      if ( !invoke_class_control(rhport, driver, p_request) ) {
+      if (!invoke_class_control(rhport, driver, p_request)) {
         // For GET_INTERFACE and SET_INTERFACE, it is mandatory to respond even if the class
         // driver doesn't use alternate settings or implement this
         TU_VERIFY(TUSB_REQ_TYPE_STANDARD == p_request->bmRequestType_bit.type);
 
-        switch(p_request->bRequest) {
-          case TUSB_REQ_GET_INTERFACE:
-          case TUSB_REQ_SET_INTERFACE:
-            // Clear complete callback if driver set since it can also stall the request.
-            usbd_control_set_complete_callback(NULL);
+        // Clear complete callback if driver set since it can also stall the request.
+        usbd_control_set_complete_callback(NULL);
 
-            if (TUSB_REQ_GET_INTERFACE == p_request->bRequest) {
-              uint8_t alternate = 0;
-              tud_control_xfer(rhport, p_request, &alternate, 1);
-            }else {
-              tud_control_status(rhport, p_request);
-            }
-          break;
+        switch (p_request->bRequest) { //-V2520
+          case TUSB_REQ_GET_INTERFACE: {
+            uint8_t alternate = 0;
+            tud_control_xfer(rhport, p_request, &alternate, 1);
+            break;
+          }
+
+          case TUSB_REQ_SET_INTERFACE:
+            tud_control_status(rhport, p_request);
+            break;
 
           default: return false;
         }
@@ -973,15 +970,15 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
       TU_ASSERT(ep_num < TU_ARRAY_SIZE(_usbd_dev.ep2drv) );
       usbd_class_driver_t const * driver = get_driver(_usbd_dev.ep2drv[ep_num][ep_dir]);
 
-      if ( TUSB_REQ_TYPE_STANDARD != p_request->bmRequestType_bit.type ) {
+      if (TUSB_REQ_TYPE_STANDARD != p_request->bmRequestType_bit.type) {
         // Forward class request to its driver
         TU_VERIFY(driver);
         return invoke_class_control(rhport, driver, p_request);
       } else {
         // Handle STD request to endpoint
-        switch ( p_request->bRequest ) {
+        switch (p_request->bRequest) { //-V2520
           case TUSB_REQ_GET_STATUS: {
-            uint16_t status = usbd_edpt_stalled(rhport, ep_addr) ? 0x0001 : 0x0000;
+            uint16_t status = usbd_edpt_stalled(rhport, ep_addr) ? 0x0001u : 0x0000u;
             tud_control_xfer(rhport, p_request, &status, 2);
           }
           break;
@@ -996,7 +993,7 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
               }
             }
 
-            if (driver) {
+            if (driver != NULL) {
               // Some classes such as USBTMC needs to clear/re-init its buffer when receiving CLEAR_FEATURE request
               // We will also forward std request targeted endpoint to class drivers as well
 
@@ -1006,7 +1003,9 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
               usbd_control_set_complete_callback(NULL);
 
               // skip ZLP status if driver already did that
-              if ( !_usbd_dev.ep_status[0][TUSB_DIR_IN].busy ) tud_control_status(rhport, p_request);
+              if (!_usbd_dev.ep_status[0][TUSB_DIR_IN].busy) {
+                tud_control_status(rhport, p_request);
+              }
             }
           }
           break;
@@ -1017,8 +1016,8 @@ static bool process_control_request(uint8_t rhport, tusb_control_request_t const
             return false;
         }
       }
+      break;
     }
-    break;
 
     // Unknown recipient
     default:
@@ -1081,10 +1080,11 @@ static bool process_set_config(uint8_t rhport, uint8_t cfg_num)
 
         // Some drivers use 2 or more interfaces but may not have IAD e.g MIDI (always) or
         // BTH (even CDC) with class in device descriptor (single interface)
-        if ( assoc_itf_count == 1)
-        {
+        if (assoc_itf_count == 1) {
           #if CFG_TUD_CDC
-          if ( driver->open == cdcd_open ) assoc_itf_count = 2;
+          if ( driver->open == cdcd_open ) {
+            assoc_itf_count = 2;
+          }
           #endif
 
           #if CFG_TUD_MIDI
@@ -1158,8 +1158,7 @@ static bool process_get_descriptor(uint8_t rhport, tusb_control_request_t const
   tusb_desc_type_t const desc_type = (tusb_desc_type_t) tu_u16_high(p_request->wValue);
   uint8_t const desc_index = tu_u16_low( p_request->wValue );
 
-  switch(desc_type)
-  {
+  switch(desc_type) { //-V2520
     case TUSB_DESC_DEVICE: {
       TU_LOG_USBD(" Device\r\n");
 
@@ -1187,7 +1186,7 @@ static bool process_get_descriptor(uint8_t rhport, tusb_control_request_t const
 
       // requested by host if USB > 2.0 ( i.e 2.1 or 3.x )
       uintptr_t desc_bos = (uintptr_t) tud_descriptor_bos_cb();
-      TU_VERIFY(desc_bos);
+      TU_VERIFY(desc_bos != 0);
 
       // Use offsetof to avoid pointer to the odd/misaligned address
       uint16_t const total_len = tu_le16toh( tu_unaligned_read16((const void*) (desc_bos + offsetof(tusb_desc_bos_t, wTotalLength))) );
@@ -1203,12 +1202,12 @@ static bool process_get_descriptor(uint8_t rhport, tusb_control_request_t const
       if ( desc_type == TUSB_DESC_CONFIGURATION ) {
         TU_LOG_USBD(" Configuration[%u]\r\n", desc_index);
         desc_config = (uintptr_t) tud_descriptor_configuration_cb(desc_index);
-        TU_ASSERT(desc_config);
+        TU_ASSERT(desc_config != 0);
       }else {
         // Host only request this after getting Device Qualifier descriptor
         TU_LOG_USBD(" Other Speed Configuration\r\n");
         desc_config = (uintptr_t) tud_descriptor_other_speed_configuration_cb(desc_index);
-        TU_VERIFY(desc_config);
+        TU_VERIFY(desc_config != 0);
       }
 
       // Use offsetof to avoid pointer to the odd/misaligned address
@@ -1218,8 +1217,7 @@ static bool process_get_descriptor(uint8_t rhport, tusb_control_request_t const
     }
     // break; // unreachable
 
-    case TUSB_DESC_STRING:
-    {
+    case TUSB_DESC_STRING: {
       TU_LOG_USBD(" String[%u]\r\n", desc_index);
 
       // String Descriptor always uses the desc set from user
diff --git a/src/device/usbd.h b/src/device/usbd.h
index bfff23399..c446638c3 100644
--- a/src/device/usbd.h
+++ b/src/device/usbd.h
@@ -95,7 +95,9 @@ bool tud_suspended(void);
 // Check if device is ready to transfer
 TU_ATTR_ALWAYS_INLINE static inline
 bool tud_ready(void) {
-  return tud_mounted() && !tud_suspended();
+  const bool is_mounted = tud_mounted();
+  const bool is_suspended = tud_suspended();
+  return is_mounted && !is_suspended;
 }
 
 // Remote wake up host, only if suspended and enabled by host
@@ -421,7 +423,7 @@ bool tud_vendor_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_requ
   TUD_AUDIO10_DESC_SELECTOR_UNIT_ONE_PIN_LEN, TUSB_DESC_CS_INTERFACE, AUDIO10_CS_AC_INTERFACE_SELECTOR_UNIT, _unitid, 1, _srcid, _stridx
 
 /* Feature Unit Descriptor UAC1 (4.3.2.5) - Variable Channels */
-#define TUD_AUDIO10_DESC_FEATURE_UNIT_LEN(_nchannels) (7 + (_nchannels + 1) * 2)
+#define TUD_AUDIO10_DESC_FEATURE_UNIT_LEN(_nchannels) (7 + ((_nchannels) + 1) * 2)
 // Feature Unit descriptor, take list of control bitmaps for master channel + each channel as variable arguments
 #define TUD_AUDIO10_DESC_FEATURE_UNIT(_unitid, _srcid, _stridx, ...) \
   TUD_AUDIO10_DESC_FEATURE_UNIT_LEN(TU_ARGS_NUM(__VA_ARGS__) - 1), TUSB_DESC_CS_INTERFACE, AUDIO10_CS_AC_INTERFACE_FEATURE_UNIT, _unitid, _srcid, 2, TU_ARGS_APPLY_EXPAND(U16_TO_U8S_LE, __VA_ARGS__), _stridx
@@ -539,7 +541,7 @@ bool tud_vendor_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_requ
   TUD_AUDIO20_DESC_OUTPUT_TERM_LEN, TUSB_DESC_CS_INTERFACE, AUDIO20_CS_AC_INTERFACE_OUTPUT_TERMINAL, _termid, U16_TO_U8S_LE(_termtype), _assocTerm, _srcid, _clkid, U16_TO_U8S_LE(_ctrl), _stridx
 
 /* Feature Unit Descriptor(4.7.2.8) */
-#define TUD_AUDIO20_DESC_FEATURE_UNIT_LEN(_nchannels) (6 + (_nchannels + 1) * 4)
+#define TUD_AUDIO20_DESC_FEATURE_UNIT_LEN(_nchannels) (6 + ((_nchannels) + 1) * 4)
 #define TUD_AUDIO20_DESC_FEATURE_UNIT(_unitid, _srcid, _stridx, ...) \
   TUD_AUDIO20_DESC_FEATURE_UNIT_LEN(TU_ARGS_NUM(__VA_ARGS__) - 1), TUSB_DESC_CS_INTERFACE, AUDIO20_CS_AC_INTERFACE_FEATURE_UNIT, _unitid, _srcid, TU_ARGS_APPLY_EXPAND(U32_TO_U8S_LE, __VA_ARGS__), _stridx
 
@@ -728,7 +730,7 @@ bool tud_vendor_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_requ
 
 //   Calculate wMaxPacketSize of Endpoints
 #define TUD_AUDIO_EP_SIZE(_is_highspeed, _maxFrequency, _nBytesPerSample, _nChannels) \
-    ((((_maxFrequency + (_is_highspeed ? 7999 : 999)) / (_is_highspeed ? 8000 : 1000)) + 1) * _nBytesPerSample * _nChannels)
+    (((((_maxFrequency) + ((_is_highspeed) ? 7999 : 999)) / ((_is_highspeed) ? 8000 : 1000)) + 1) * (_nBytesPerSample) * (_nChannels))
 
 
 //--------------------------------------------------------------------+
@@ -807,44 +809,44 @@ bool tud_vendor_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_requ
 // Interface number, Alternate count, starting string index, attributes, detach timeout, transfer size
 // Note: Alternate count must be numeric or macro, string index is increased by one for each Alt interface
 #define TUD_DFU_DESCRIPTOR(_itfnum, _alt_count, _stridx, _attr, _timeout, _xfer_size) \
-  TU_XSTRCAT(_TUD_DFU_ALT_,_alt_count)(_itfnum, 0, _stridx), \
+  TU_XSTRCAT(TUD_DFU_ALT_,_alt_count)(_itfnum, 0, _stridx), \
   /* Function */ \
   9, DFU_DESC_FUNCTIONAL, _attr, U16_TO_U8S_LE(_timeout), U16_TO_U8S_LE(_xfer_size), U16_TO_U8S_LE(0x0101)
 
-#define _TUD_DFU_ALT(_itfnum, _alt, _stridx) \
+#define TUD_DFU_ALT(_itfnum, _alt, _stridx) \
   /* Interface */ \
   9, TUSB_DESC_INTERFACE, _itfnum, _alt, 0, TUD_DFU_APP_CLASS, TUD_DFU_APP_SUBCLASS, DFU_PROTOCOL_DFU, _stridx
 
-#define _TUD_DFU_ALT_1(_itfnum, _alt_count, _stridx) \
-  _TUD_DFU_ALT(_itfnum, _alt_count, _stridx)
+#define TUD_DFU_ALT_1(_itfnum, _alt_count, _stridx) \
+  TUD_DFU_ALT(_itfnum, _alt_count, _stridx)
 
-#define _TUD_DFU_ALT_2(_itfnum, _alt_count, _stridx) \
-  _TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
-  _TUD_DFU_ALT_1(_itfnum, _alt_count+1, _stridx+1)
+#define TUD_DFU_ALT_2(_itfnum, _alt_count, _stridx) \
+  TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
+  TUD_DFU_ALT_1(_itfnum, _alt_count+1, _stridx+1)
 
-#define _TUD_DFU_ALT_3(_itfnum, _alt_count, _stridx) \
-  _TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
-  _TUD_DFU_ALT_2(_itfnum, _alt_count+1, _stridx+1)
+#define TUD_DFU_ALT_3(_itfnum, _alt_count, _stridx) \
+  TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
+  TUD_DFU_ALT_2(_itfnum, _alt_count+1, _stridx+1)
 
-#define _TUD_DFU_ALT_4(_itfnum, _alt_count, _stridx) \
-  _TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
-  _TUD_DFU_ALT_3(_itfnum, _alt_count+1, _stridx+1)
+#define TUD_DFU_ALT_4(_itfnum, _alt_count, _stridx) \
+  TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
+  TUD_DFU_ALT_3(_itfnum, _alt_count+1, _stridx+1)
 
-#define _TUD_DFU_ALT_5(_itfnum, _alt_count, _stridx) \
-  _TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
-  _TUD_DFU_ALT_4(_itfnum, _alt_count+1, _stridx+1)
+#define TUD_DFU_ALT_5(_itfnum, _alt_count, _stridx) \
+  TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
+  TUD_DFU_ALT_4(_itfnum, _alt_count+1, _stridx+1)
 
-#define _TUD_DFU_ALT_6(_itfnum, _alt_count, _stridx) \
-  _TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
-  _TUD_DFU_ALT_5(_itfnum, _alt_count+1, _stridx+1)
+#define TUD_DFU_ALT_6(_itfnum, _alt_count, _stridx) \
+  TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
+  TUD_DFU_ALT_5(_itfnum, _alt_count+1, _stridx+1)
 
-#define _TUD_DFU_ALT_7(_itfnum, _alt_count, _stridx) \
-  _TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
-  _TUD_DFU_ALT_6(_itfnum, _alt_count+1, _stridx+1)
+#define TUD_DFU_ALT_7(_itfnum, _alt_count, _stridx) \
+  TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
+  TUD_DFU_ALT_6(_itfnum, _alt_count+1, _stridx+1)
 
-#define _TUD_DFU_ALT_8(_itfnum, _alt_count, _stridx) \
-  _TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
-  _TUD_DFU_ALT_7(_itfnum, _alt_count+1, _stridx+1)
+#define TUD_DFU_ALT_8(_itfnum, _alt_count, _stridx) \
+  TUD_DFU_ALT(_itfnum, _alt_count, _stridx),      \
+  TUD_DFU_ALT_7(_itfnum, _alt_count+1, _stridx+1)
 
 //--------------------------------------------------------------------+
 // CDC-ECM Descriptor Templates
diff --git a/src/device/usbd_pvt.h b/src/device/usbd_pvt.h
index a688cf497..2894d3023 100644
--- a/src/device/usbd_pvt.h
+++ b/src/device/usbd_pvt.h
@@ -117,7 +117,9 @@ bool usbd_edpt_iso_activate(uint8_t rhport,  tusb_desc_endpoint_t const * p_endp
 // Check if endpoint is ready (not busy and not stalled)
 TU_ATTR_ALWAYS_INLINE static inline
 bool usbd_edpt_ready(uint8_t rhport, uint8_t ep_addr) {
-  return !usbd_edpt_busy(rhport, ep_addr) && !usbd_edpt_stalled(rhport, ep_addr);
+  const bool is_busy = usbd_edpt_busy(rhport, ep_addr);
+  const bool is_stalled = usbd_edpt_stalled(rhport, ep_addr);
+  return !is_busy && !is_stalled;
 }
 
 // Enable SOF interrupt
diff --git a/src/portable/synopsys/dwc2/dcd_dwc2.c b/src/portable/synopsys/dwc2/dcd_dwc2.c
index 1b43b9ac4..b2531426a 100644
--- a/src/portable/synopsys/dwc2/dcd_dwc2.c
+++ b/src/portable/synopsys/dwc2/dcd_dwc2.c
@@ -85,6 +85,12 @@ TU_ATTR_ALWAYS_INLINE static inline uint8_t dwc2_ep_count(const dwc2_regs_t* dwc
   #endif
 }
 
+//--------------------------------------------------------------------+
+//
+//--------------------------------------------------------------------+
+TU_ATTR_ALWAYS_INLINE static inline bool edpt_is_enabled(dwc2_dep_t* dep) {
+  return (dep->ctl & EPCTL_EPENA) != 0;
+}
 
 //--------------------------------------------------------------------
 // DMA
@@ -117,7 +123,7 @@ static void dma_setup_prepare(uint8_t rhport) {
   dwc2_regs_t* dwc2 = DWC2_REG(rhport);
 
   if (dwc2->gsnpsid >= DWC2_CORE_REV_3_00a) {
-    if(dwc2->epout[0].doepctl & DOEPCTL_EPENA) {
+    if(edpt_is_enabled(&dwc2->epout[0])) {
       return;
     }
   }
@@ -200,7 +206,7 @@ static bool dfifo_alloc(uint8_t rhport, uint8_t ep_addr, uint16_t packet_size) {
     }
   } else {
     // Check IN endpoints concurrently active limit
-    if(dwc2_controller->ep_in_count) {
+    if(0 != dwc2_controller->ep_in_count) {
       TU_ASSERT(_dcd_data.allocated_epin_count < dwc2_controller->ep_in_count);
       _dcd_data.allocated_epin_count++;
     }
@@ -217,10 +223,10 @@ static bool dfifo_alloc(uint8_t rhport, uint8_t ep_addr, uint16_t packet_size) {
 
     // Both TXFD and TXSA are in unit of 32-bit words.
     if (epnum == 0) {
-      dwc2->dieptxf0 = (fifo_size << DIEPTXF0_TX0FD_Pos) | _dcd_data.dfifo_top;
+      dwc2->dieptxf0 = ((uint32_t) fifo_size << DIEPTXF0_TX0FD_Pos) | _dcd_data.dfifo_top;
     } else {
       // DIEPTXF starts at FIFO #1.
-      dwc2->dieptxf[epnum - 1] = (fifo_size << DIEPTXF_INEPTXFD_Pos) | _dcd_data.dfifo_top;
+      dwc2->dieptxf[epnum - 1] = ((uint32_t) fifo_size << DIEPTXF_INEPTXFD_Pos) | _dcd_data.dfifo_top;
     }
   }
 
@@ -238,10 +244,10 @@ static void dfifo_device_init(uint8_t rhport) {
   if (is_dma) {
     _dcd_data.dfifo_top -= 2 * dwc2_controller->ep_count;
   }
-  dwc2->gdfifocfg = (_dcd_data.dfifo_top << GDFIFOCFG_EPINFOBASE_SHIFT) | _dcd_data.dfifo_top;
+  dwc2->gdfifocfg = ((uint32_t) _dcd_data.dfifo_top << GDFIFOCFG_EPINFOBASE_SHIFT) | _dcd_data.dfifo_top;
 
   // Allocate FIFO for EP0 IN
-  dfifo_alloc(rhport, 0x80, CFG_TUD_ENDPOINT0_SIZE);
+  (void) dfifo_alloc(rhport, 0x80, CFG_TUD_ENDPOINT0_SIZE);
 }
 
 
@@ -282,16 +288,18 @@ static void edpt_disable(uint8_t rhport, uint8_t ep_addr, bool stall) {
   const uint8_t dir = tu_edpt_dir(ep_addr);
   dwc2_dep_t* dep = &dwc2->ep[dir == TUSB_DIR_IN ? 0 : 1][epnum];
 
+  const uint32_t stall_mask = (stall ? EPCTL_STALL : 0);
+
   if (dir == TUSB_DIR_IN) {
-    if (!(dep->diepctl & DIEPCTL_EPENA)) {
-      dep->diepctl |= DIEPCTL_SNAK | (stall ? DIEPCTL_STALL : 0);
+    if (!edpt_is_enabled(dep)) {
+      dep->diepctl |= DIEPCTL_SNAK | stall_mask;
     } else {
       // Stop transmitting packets and NAK IN xfers.
       dep->diepctl |= DIEPCTL_SNAK;
       while ((dep->diepint & DIEPINT_INEPNE) == 0) {}
 
       // Disable the endpoint.
-      dep->diepctl |= DIEPCTL_EPDIS | (stall ? DIEPCTL_STALL : 0);
+      dep->diepctl |= DIEPCTL_EPDIS | stall_mask;
       while ((dep->diepint & DIEPINT_EPDISD_Msk) == 0) {}
 
       dep->diepint = DIEPINT_EPDISD;
@@ -300,9 +308,10 @@ static void edpt_disable(uint8_t rhport, uint8_t ep_addr, bool stall) {
     // Flush the FIFO, and wait until we have confirmed it cleared.
     dfifo_flush_tx(dwc2, epnum);
   } else {
-    // Only disable currently enabled non-control endpoint
-    if ((epnum == 0) || !(dep->doepctl & DOEPCTL_EPENA)) {
-      dep->doepctl |= stall ? DOEPCTL_STALL : 0;
+    if (!edpt_is_enabled(dep) || epnum == 0) {
+      // non-control not-enabled: stall if set
+      // For EP0 Out, keep it enabled to receive SETUP packets
+      dep->doepctl |= stall_mask;
     } else {
       // Asserting GONAK is required to STALL an OUT endpoint.
       // Simpler to use polling here, we don't use the "B"OUTNAKEFF interrupt
@@ -312,7 +321,7 @@ static void edpt_disable(uint8_t rhport, uint8_t ep_addr, bool stall) {
       while ((dwc2->gintsts & GINTSTS_BOUTNAKEFF_Msk) == 0) {}
 
       // Ditto here disable the endpoint.
-      dep->doepctl |= DOEPCTL_EPDIS | (stall ? DOEPCTL_STALL : 0);
+      dep->doepctl |= DOEPCTL_EPDIS | stall_mask;
       while ((dep->doepint & DOEPINT_EPDISD_Msk) == 0) {}
 
       dep->doepint = DOEPINT_EPDISD;
@@ -360,7 +369,7 @@ static void edpt_schedule_packets(uint8_t rhport, const uint8_t epnum, const uin
   if (depctl.type == DEPCTL_EPTYPE_ISOCHRONOUS && xfer->interval == 1) {
     const dwc2_dsts_t dsts = {.value = dwc2->dsts};
     const uint32_t odd_now = dsts.frame_number & 1u;
-    if (odd_now) {
+    if (odd_now != 0) {
       depctl.set_data0_iso_even = 1;
     } else {
       depctl.set_data1_iso_odd = 1;
@@ -379,7 +388,7 @@ static void edpt_schedule_packets(uint8_t rhport, const uint8_t epnum, const uin
 
     // Enable tx fifo empty interrupt only if there is data. Note must after depctl enable
     if (dir == TUSB_DIR_IN && total_bytes != 0) {
-      dwc2->diepempmsk |= (1u << epnum);
+      dwc2->diepempmsk |= (1u << epnum); //-V629
     }
   }
 }
@@ -551,7 +560,7 @@ void dcd_edpt_close_all(uint8_t rhport) {
   for (uint8_t n = 1; n < ep_count; n++) {
     for (uint8_t d = 0; d < 2; d++) {
       dwc2_dep_t* dep = &dwc2->ep[d][n];
-      if (dep->ctl & EPCTL_EPENA) {
+      if (edpt_is_enabled(dep)) {
         dep->ctl |= EPCTL_SNAK | EPCTL_EPDIS;
       }
       xfer_status[n][1-d].max_size = 0;
@@ -643,8 +652,12 @@ bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t* ff, uint16_t
 void dcd_edpt_stall(uint8_t rhport, uint8_t ep_addr) {
   dwc2_regs_t* dwc2 = DWC2_REG(rhport);
   edpt_disable(rhport, ep_addr, true);
-  if((tu_edpt_number(ep_addr) == 0) && dma_device_enabled(dwc2)) {
-    dma_setup_prepare(rhport);
+
+  // For control endpoint, prepare to receive SETUP packet
+  if (tu_edpt_number(ep_addr) == 0) {
+    if (dma_device_enabled(dwc2)) {
+      dma_setup_prepare(rhport);
+    }
   }
 }
 
@@ -681,8 +694,9 @@ static void handle_bus_reset(uint8_t rhport) {
 
   // Disable all IN endpoints
   for (uint8_t n = 0; n < ep_count; n++) {
-    if (dwc2->epin[n].diepctl & DIEPCTL_EPENA) {
-      dwc2->epin[n].diepctl |= DIEPCTL_SNAK | DIEPCTL_EPDIS;
+    dwc2_dep_t* dep = &dwc2->epin[n];
+    if (edpt_is_enabled(dep)) {
+      dep->diepctl |= DIEPCTL_SNAK | DIEPCTL_EPDIS;
     }
   }
 
@@ -807,9 +821,9 @@ static void handle_rxflvl_irq(uint8_t rhport) {
       const uint16_t byte_count = grxstsp.byte_count;
       xfer_ctl_t* xfer = XFER_CTL_BASE(epnum, TUSB_DIR_OUT);
 
-      if (byte_count) {
+      if (byte_count != 0) {
         // Read packet off RxFIFO
-        if (xfer->ff) {
+        if (xfer->ff != NULL) {
           tu_fifo_write_n_const_addr_full_words(xfer->ff, (const void*) (uintptr_t) rx_fifo, byte_count);
         } else {
           dfifo_read_packet(dwc2, xfer->buffer, byte_count);
@@ -836,7 +850,7 @@ static void handle_rxflvl_irq(uint8_t rhport) {
       // the specified OUT endpoint which will be handled by handle_epout_irq()
       break;
 
-    default: break;
+    default: break; // nothing to do
   }
 }
 
@@ -844,7 +858,7 @@ static void handle_epout_slave(uint8_t rhport, uint8_t epnum, dwc2_doepint_t doe
   if (doepint_bm.setup_phase_done) {
     // Cleanup previous pending EP0 IN transfer if any
     dwc2_dep_t* epin0 = &DWC2_REG(rhport)->epin[0];
-    if (epin0->diepctl & DIEPCTL_EPENA) {
+    if (edpt_is_enabled(epin0)) {
       edpt_disable(rhport, 0x80, false);
     }
     dcd_event_setup_received(rhport, _dcd_usbbuf.setup_packet, true);
@@ -858,7 +872,6 @@ static void handle_epout_slave(uint8_t rhport, uint8_t epnum, dwc2_doepint_t doe
     // can is set when GRXSTS_PKTSTS_SETUP_RX is popped therefore they can bet set before/together with setup_phase_done
     if (!doepint_bm.status_phase_rx && !doepint_bm.setup_packet_rx) {
       xfer_ctl_t* xfer = XFER_CTL_BASE(epnum, TUSB_DIR_OUT);
-
       if ((epnum == 0) && _dcd_data.ep0_pending[TUSB_DIR_OUT]) {
         // EP0 can only handle one packet, Schedule another packet to be received.
         edpt_schedule_packets(rhport, epnum, TUSB_DIR_OUT);
@@ -875,7 +888,7 @@ static void handle_epin_slave(uint8_t rhport, uint8_t epnum, dwc2_diepint_t diep
   xfer_ctl_t* xfer = XFER_CTL_BASE(epnum, TUSB_DIR_IN);
 
   if (diepint_bm.xfer_complete) {
-    if ((epnum == 0) && _dcd_data.ep0_pending[TUSB_DIR_IN]) {
+    if ((epnum == 0) && (0 != _dcd_data.ep0_pending[TUSB_DIR_IN])) {
       // EP0 can only handle one packet. Schedule another packet to be transmitted.
       edpt_schedule_packets(rhport, epnum, TUSB_DIR_IN);
     } else {
@@ -886,7 +899,7 @@ static void handle_epin_slave(uint8_t rhport, uint8_t epnum, dwc2_diepint_t diep
   // TX FIFO empty bit is read-only. It will only be cleared by hardware when written bytes is more than
   // - 64 bytes or
   // - Half/Empty of TX FIFO size (configured by GAHBCFG.TXFELVL)
-  if (diepint_bm.txfifo_empty && (dwc2->diepempmsk & (1 << epnum))) {
+  if (diepint_bm.txfifo_empty && tu_bit_test(dwc2->diepempmsk, epnum)) {
     dwc2_ep_tsize_t tsiz = {.value = epin->tsiz};
     const uint16_t remain_packets = tsiz.packet_count;
 
@@ -902,7 +915,7 @@ static void handle_epin_slave(uint8_t rhport, uint8_t epnum, dwc2_diepint_t diep
       }
 
       // Push packet to Tx-FIFO
-      if (xfer->ff) {
+      if (xfer->ff != NULL) {
         volatile uint32_t* tx_fifo = dwc2->fifo[epnum];
         tu_fifo_read_n_const_addr_full_words(xfer->ff, (void*)(uintptr_t)tx_fifo, xact_bytes);
       } else {
@@ -927,7 +940,7 @@ static void handle_epout_dma(uint8_t rhport, uint8_t epnum, dwc2_doepint_t doepi
   if (doepint_bm.setup_phase_done) {
     // Cleanup previous pending EP0 IN transfer if any
     dwc2_dep_t* epin0 = &DWC2_REG(rhport)->epin[0];
-    if (epin0->diepctl & DIEPCTL_EPENA) {
+    if (edpt_is_enabled(epin0)) {
       edpt_disable(rhport, 0x80, false);
     }
     dma_setup_prepare(rhport);
@@ -993,7 +1006,7 @@ static void handle_ep_irq(uint8_t rhport, uint8_t dir) {
   // DAINT for a given EP clears when DEPINTx is cleared.
   // EPINT will be cleared when DAINT bits are cleared.
   for (uint8_t epnum = 0; epnum < ep_count; epnum++) {
-    if (dwc2->daint & TU_BIT(daint_offset + epnum)) {
+    if (tu_bit_test(dwc2->daint,daint_offset + epnum)) {
       dwc2_dep_t* epout = &ep_base[epnum];
       union {
         uint32_t value;
@@ -1002,7 +1015,7 @@ static void handle_ep_irq(uint8_t rhport, uint8_t dir) {
       } intr;
       intr.value = epout->intr;
 
-      epout->intr = intr.value; // Clear interrupt
+      epout->intr = intr.value; // Clear interrupt //-V::2584::{otg_int}
 
       if (is_dma) {
         #if CFG_TUD_DWC2_DMA_ENABLE
@@ -1037,6 +1050,7 @@ static void handle_ep_irq(uint8_t rhport, uint8_t dir) {
   Note: when OTG_MULTI_PROC_INTRPT = 1, Device Each endpoint interrupt deachint/deachmsk/diepeachmsk/doepeachmsk
   are combined to generate dedicated interrupt line for each endpoint.
  */
+//-V::2584::{gintsts} PVS-Studio suppression
 void dcd_int_handler(uint8_t rhport) {
   dwc2_regs_t* dwc2 = DWC2_REG(rhport);
   const uint32_t gintmask = dwc2->gintmsk;
diff --git a/src/portable/synopsys/dwc2/dwc2_stm32.h b/src/portable/synopsys/dwc2/dwc2_stm32.h
index 08950ccc0..9da8de41f 100644
--- a/src/portable/synopsys/dwc2/dwc2_stm32.h
+++ b/src/portable/synopsys/dwc2/dwc2_stm32.h
@@ -176,7 +176,9 @@ TU_ATTR_ALWAYS_INLINE static inline void dwc2_int_set(uint8_t rhport, tusb_role_
 TU_ATTR_ALWAYS_INLINE static inline void dwc2_remote_wakeup_delay(void) {
   // try to delay for 1 ms
   uint32_t count = SystemCoreClock / 1000;
-  while (count--) __NOP();
+  while (count--) {
+    __NOP();
+  }
 }
 
 // MCU specific PHY init, called BEFORE core reset
diff --git a/src/portable/synopsys/dwc2/dwc2_type.h b/src/portable/synopsys/dwc2/dwc2_type.h
index 75643529f..adcc579e3 100644
--- a/src/portable/synopsys/dwc2/dwc2_type.h
+++ b/src/portable/synopsys/dwc2/dwc2_type.h
@@ -1435,7 +1435,7 @@ TU_VERIFY_STATIC(offsetof(dwc2_regs_t, fifo   ) == 0x1000, "incorrect size");
 #define DAINTMSK_OEPM_Msk                (0xFFFFUL << DAINTMSK_OEPM_Pos)          // 0xFFFF0000
 #define DAINTMSK_OEPM                    DAINTMSK_OEPM_Msk                        // OUT EP interrupt mask bits
 
-#define DAINT_SHIFT(_dir)            ((_dir == TUSB_DIR_IN) ? 0 : 16)
+#define DAINT_SHIFT(_dir)                (((_dir) == TUSB_DIR_IN) ? 0 : 16)
 
 #if 0
 /********************  Bit definition for OTG register  ********************/