From 31bd4fc169eb002ded3f23e8a6a0b95f3f591efb Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 22 Oct 2025 05:28:31 +0000
Subject: [PATCH] Add is_isr parameter to dcd_edpt_xfer and dcd_edpt_xfer_fifo

Co-authored-by: HiFiPhile <4375114+HiFiPhile@users.noreply.github.com>
---
 src/device/dcd.h                                |  4 ++--
 src/device/usbd.c                               |  8 ++++----
 src/portable/bridgetek/ft9xx/dcd_ft9xx.c        |  9 ++++++---
 src/portable/chipidea/ci_fs/dcd_ci_fs.c         |  6 ++++--
 src/portable/chipidea/ci_hs/dcd_ci_hs.c         |  9 ++++++---
 src/portable/dialog/da146xx/dcd_da146xx.c       |  6 ++++--
 src/portable/mentor/musb/dcd_musb.c             |  7 +++++--
 src/portable/microchip/pic/dcd_pic.c            |  6 ++++--
 src/portable/microchip/pic32mz/dcd_pic32mz.c    |  4 +++-
 src/portable/microchip/samd/dcd_samd.c          |  6 ++++--
 src/portable/microchip/samg/dcd_samg.c          |  9 ++++++---
 src/portable/microchip/samx7x/dcd_samx7x.c      |  9 ++++++---
 .../mindmotion/mm32/dcd_mm32f327x_otg.c         |  6 ++++--
 src/portable/nordic/nrf5x/dcd_nrf5x.c           |  4 +++-
 src/portable/nuvoton/nuc120/dcd_nuc120.c        |  7 +++++--
 src/portable/nuvoton/nuc121/dcd_nuc121.c        |  7 +++++--
 src/portable/nuvoton/nuc505/dcd_nuc505.c        |  7 +++++--
 src/portable/nxp/khci/dcd_khci.c                |  6 ++++--
 src/portable/nxp/lpc17_40/dcd_lpc17_40.c        |  6 ++++--
 src/portable/nxp/lpc_ip3511/dcd_lpc_ip3511.c    |  7 +++++--
 src/portable/raspberrypi/pio_usb/dcd_pio_usb.c  |  8 +++++---
 src/portable/raspberrypi/rp2040/dcd_rp2040.c    |  4 +++-
 src/portable/renesas/rusb2/dcd_rusb2.c          |  7 +++++--
 src/portable/sony/cxd56/dcd_cxd56.c             |  4 +++-
 src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c   |  9 ++++++---
 src/portable/sunxi/dcd_sunxi_musb.c             |  7 +++++--
 src/portable/synopsys/dwc2/dcd_dwc2.c           | 17 ++++++++++-------
 src/portable/template/dcd_template.c            |  7 +++++--
 src/portable/ti/msp430x5xx/dcd_msp430x5xx.c     |  9 ++++++---
 src/portable/valentyusb/eptri/dcd_eptri.c       |  6 ++++--
 src/portable/wch/dcd_ch32_usbfs.c               |  6 ++++--
 src/portable/wch/dcd_ch32_usbhs.c               |  6 ++++--
 .../unit-test/test/device/msc/test_msc_device.c | 10 +++++-----
 test/unit-test/test/device/usbd/test_usbd.c     | 16 ++++++++--------
 34 files changed, 162 insertions(+), 87 deletions(-)

diff --git a/src/device/dcd.h b/src/device/dcd.h
index 400f62bff..f90156235 100644
--- a/src/device/dcd.h
+++ b/src/device/dcd.h
@@ -158,11 +158,11 @@ bool dcd_edpt_open            (uint8_t rhport, tusb_desc_endpoint_t const * desc
 void dcd_edpt_close_all       (uint8_t rhport);
 
 // Submit a transfer, When complete dcd_event_xfer_complete() is invoked to notify the stack
-bool dcd_edpt_xfer            (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes);
+bool dcd_edpt_xfer            (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr);
 
 // Submit an transfer using fifo, When complete dcd_event_xfer_complete() is invoked to notify the stack
 // This API is optional, may be useful for register-based for transferring data.
-bool dcd_edpt_xfer_fifo       (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes);
+bool dcd_edpt_xfer_fifo       (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr);
 
 // Stall endpoint, any queuing transfer should be removed from endpoint
 void dcd_edpt_stall           (uint8_t rhport, uint8_t ep_addr);
diff --git a/src/device/usbd.c b/src/device/usbd.c
index 339ccf4b4..d5ebcc66b 100644
--- a/src/device/usbd.c
+++ b/src/device/usbd.c
@@ -415,8 +415,8 @@ TU_ATTR_WEAK usbd_class_driver_t const* usbd_app_driver_get_cb(uint8_t* driver_c
   return NULL;
 }
 
-TU_ATTR_WEAK bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes) {
-  (void) rhport; (void) ep_addr; (void) ff; (void) total_bytes;
+TU_ATTR_WEAK bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr) {
+  (void) rhport; (void) ep_addr; (void) ff; (void) total_bytes; (void) is_isr;
   return false;
 }
 
@@ -1433,7 +1433,7 @@ bool usbd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t t
   // could return and USBD task can preempt and clear the busy
   _usbd_dev.ep_status[epnum][dir].busy = 1;
 
-  if (dcd_edpt_xfer(rhport, ep_addr, buffer, total_bytes)) {
+  if (dcd_edpt_xfer(rhport, ep_addr, buffer, total_bytes, false)) {
     return true;
   } else {
     // DCD error, mark endpoint as ready to allow next transfer
@@ -1464,7 +1464,7 @@ bool usbd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t* ff, uint16_
   // and usbd task can preempt and clear the busy
   _usbd_dev.ep_status[epnum][dir].busy = 1;
 
-  if (dcd_edpt_xfer_fifo(rhport, ep_addr, ff, total_bytes)) {
+  if (dcd_edpt_xfer_fifo(rhport, ep_addr, ff, total_bytes, false)) {
     TU_LOG_USBD("OK\r\n");
     return true;
   } else {
diff --git a/src/portable/bridgetek/ft9xx/dcd_ft9xx.c b/src/portable/bridgetek/ft9xx/dcd_ft9xx.c
index 34a8be3b6..f6def44ab 100644
--- a/src/portable/bridgetek/ft9xx/dcd_ft9xx.c
+++ b/src/portable/bridgetek/ft9xx/dcd_ft9xx.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -556,7 +557,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
   (void)dev_addr;
 
   // Respond with status. There is no checking that the address is in range.
-  dcd_edpt_xfer(rhport, tu_edpt_addr(USBD_EP_0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(USBD_EP_0, TUSB_DIR_IN), NULL, 0, false);
 
   // Set the update bit for the address register.
   dev_addr |= 0x80;
@@ -807,8 +808,9 @@ void dcd_edpt_close_all(uint8_t rhport)
 }
 
 // Submit a transfer, When complete dcd_event_xfer_complete() is invoked to notify the stack
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void)rhport;
   uint8_t ep_number = tu_edpt_number(ep_addr);
   uint8_t ep_dir = tu_edpt_dir(ep_addr);
@@ -891,8 +893,9 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t to
 }
 
 // Submit a transfer where is managed by FIFO, When complete dcd_event_xfer_complete() is invoked to notify the stack - optional, however, must be listed in usbd.c
-bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t *ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void)rhport;
   (void)ep_addr;
   (void)ff;
diff --git a/src/portable/chipidea/ci_fs/dcd_ci_fs.c b/src/portable/chipidea/ci_fs/dcd_ci_fs.c
index 11ddb683f..6bf3450ed 100644
--- a/src/portable/chipidea/ci_fs/dcd_ci_fs.c
+++ b/src/portable/chipidea/ci_fs/dcd_ci_fs.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -303,7 +304,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
 {
   _dcd.addr = dev_addr & 0x7F;
   /* Response with status first before changing device address */
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 }
 
 void dcd_remote_wakeup(uint8_t rhport)
@@ -419,8 +420,9 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr)
   dcd_int_enable(rhport);
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   const unsigned epn      = tu_edpt_number(ep_addr);
   const unsigned dir      = tu_edpt_dir(ep_addr);
   endpoint_state_t    *ep = &_dcd.endpoint[epn][dir];
diff --git a/src/portable/chipidea/ci_hs/dcd_ci_hs.c b/src/portable/chipidea/ci_hs/dcd_ci_hs.c
index 244f5a2d4..a11d2bbd1 100644
--- a/src/portable/chipidea/ci_hs/dcd_ci_hs.c
+++ b/src/portable/chipidea/ci_hs/dcd_ci_hs.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -277,7 +278,7 @@ void dcd_int_disable(uint8_t rhport)
 void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
 {
   // Response with status first before changing device address
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 
   ci_hs_regs_t* dcd_reg = CI_HS_REG(rhport);
   dcd_reg->DEVICEADDR = (dev_addr << 25) | TU_BIT(24);
@@ -465,8 +466,9 @@ static void qhd_start_xfer(uint8_t rhport, uint8_t epnum, uint8_t dir)
   dcd_reg->ENDPTPRIME = TU_BIT(epnum + (dir ? 16 : 0));
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   uint8_t const epnum = tu_edpt_number(ep_addr);
   uint8_t const dir   = tu_edpt_dir(ep_addr);
 
@@ -486,8 +488,9 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t t
 #if !CFG_TUD_MEM_DCACHE_ENABLE
 // fifo has to be aligned to 4k boundary
 // It's incompatible with dcache enabled transfer, since neither address nor size is aligned to cache line
-bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   uint8_t const epnum = tu_edpt_number(ep_addr);
   uint8_t const dir   = tu_edpt_dir(ep_addr);
 
diff --git a/src/portable/dialog/da146xx/dcd_da146xx.c b/src/portable/dialog/da146xx/dcd_da146xx.c
index 56ecb7575..8666992aa 100644
--- a/src/portable/dialog/da146xx/dcd_da146xx.c
+++ b/src/portable/dialog/da146xx/dcd_da146xx.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -837,7 +838,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
   // Set default address for one ZLP
   USB->USB_EPC0_REG = USB_USB_EPC0_REG_USB_DEF_Msk;
   USB->USB_FAR_REG = (dev_addr & USB_USB_FAR_REG_USB_AD_Msk) | USB_USB_FAR_REG_USB_AD_EN_Msk;
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 }
 
 void dcd_remote_wakeup(uint8_t rhport)
@@ -1025,8 +1026,9 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr)
   tu_memclr(xfer, sizeof(*xfer));
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   uint8_t const epnum = tu_edpt_number(ep_addr);
   uint8_t const dir   = tu_edpt_dir(ep_addr);
   xfer_ctl_t * xfer = XFER_CTL_BASE(epnum, dir);
diff --git a/src/portable/mentor/musb/dcd_musb.c b/src/portable/mentor/musb/dcd_musb.c
index 4fce08dd9..acb35fcee 100644
--- a/src/portable/mentor/musb/dcd_musb.c
+++ b/src/portable/mentor/musb/dcd_musb.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -772,8 +773,9 @@ void dcd_edpt_close_all(uint8_t rhport)
 }
 
 // Submit a transfer, When complete dcd_event_xfer_complete() is invoked to notify the stack
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void)rhport;
   bool ret;
   // TU_LOG1("X %x %d\r\n", ep_addr, total_bytes);
@@ -794,8 +796,9 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t t
 
 // Submit a transfer where is managed by FIFO, When complete dcd_event_xfer_complete() is invoked to notify the stack
 // - optional, however, must be listed in usbd.c
-bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void)rhport;
   bool ret;
   // TU_LOG1("X %x %d\r\n", ep_addr, total_bytes);
diff --git a/src/portable/microchip/pic/dcd_pic.c b/src/portable/microchip/pic/dcd_pic.c
index b4a698199..7d92056e8 100644
--- a/src/portable/microchip/pic/dcd_pic.c
+++ b/src/portable/microchip/pic/dcd_pic.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -545,7 +546,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
 {
   _dcd.addr = dev_addr & 0x7F;
   /* Response with status first before changing device address */
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 }
 
 void dcd_remote_wakeup(uint8_t rhport)
@@ -687,8 +688,9 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr)
   if (ie) intr_enable(rhport);
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
 
   const unsigned epn      = tu_edpt_number(ep_addr);
   const unsigned dir      = tu_edpt_dir(ep_addr);
diff --git a/src/portable/microchip/pic32mz/dcd_pic32mz.c b/src/portable/microchip/pic32mz/dcd_pic32mz.c
index cbd157d6b..ce53893ec 100644
--- a/src/portable/microchip/pic32mz/dcd_pic32mz.c
+++ b/src/portable/microchip/pic32mz/dcd_pic32mz.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -444,8 +445,9 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr)
   (void) ep_addr;
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   uint8_t const epnum = tu_edpt_number(ep_addr);
   uint8_t const dir   = tu_edpt_dir(ep_addr);
   xfer_ctl_t * xfer = XFER_CTL_BASE(epnum, dir);
diff --git a/src/portable/microchip/samd/dcd_samd.c b/src/portable/microchip/samd/dcd_samd.c
index e43439f2a..1ff314d39 100644
--- a/src/portable/microchip/samd/dcd_samd.c
+++ b/src/portable/microchip/samd/dcd_samd.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -142,7 +143,7 @@ void dcd_set_address (uint8_t rhport, uint8_t dev_addr)
   (void) dev_addr;
 
   // Response with zlp status
-  dcd_edpt_xfer(rhport, 0x80, NULL, 0);
+  dcd_edpt_xfer(rhport, 0x80, NULL, 0, false);
 
   // DCD can only set address after status for this request is complete
   // do it at dcd_edpt0_status_complete()
@@ -258,8 +259,9 @@ void dcd_edpt_close_all (uint8_t rhport)
   // TODO implement dcd_edpt_close_all()
 }
 
-bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   uint8_t const epnum = tu_edpt_number(ep_addr);
diff --git a/src/portable/microchip/samg/dcd_samg.c b/src/portable/microchip/samg/dcd_samg.c
index a5c768839..3ba538639 100644
--- a/src/portable/microchip/samg/dcd_samg.c
+++ b/src/portable/microchip/samg/dcd_samg.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -175,7 +176,7 @@ void dcd_set_address (uint8_t rhport, uint8_t dev_addr)
   (void) dev_addr;
 
   // Response with zlp status
-  dcd_edpt_xfer(rhport, 0x80, NULL, 0);
+  dcd_edpt_xfer(rhport, 0x80, NULL, 0, false);
 
   // DCD can only set address after status for this request is complete.
   // do it at dcd_edpt0_status_complete()
@@ -282,8 +283,9 @@ void dcd_edpt_close_all (uint8_t rhport)
 }
 
 // Submit a transfer, When complete dcd_event_xfer_complete() is invoked to notify the stack
-bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   uint8_t const epnum = tu_edpt_number(ep_addr);
@@ -309,8 +311,9 @@ bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t
 }
 
 #if 0 // TODO support dcd_edpt_xfer_fifo API
-bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
   return true;
 }
diff --git a/src/portable/microchip/samx7x/dcd_samx7x.c b/src/portable/microchip/samx7x/dcd_samx7x.c
index 8aec1568d..494c83fde 100644
--- a/src/portable/microchip/samx7x/dcd_samx7x.c
+++ b/src/portable/microchip/samx7x/dcd_samx7x.c
@@ -1,3 +1,4 @@
+
 /*
 * The MIT License (MIT)
 *
@@ -132,7 +133,7 @@ void dcd_set_address (uint8_t rhport, uint8_t dev_addr)
   // do it at dcd_edpt0_status_complete()
 
   // Response with zlp status
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 }
 
 // Wake up host
@@ -605,8 +606,9 @@ static void dcd_transmit_packet(xfer_ctl_t * xfer, uint8_t ep_ix)
 }
 
 // Submit a transfer, When complete dcd_event_xfer_complete() is invoked to notify the stack
-bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
   uint8_t const epnum = tu_edpt_number(ep_addr);
   uint8_t const dir   = tu_edpt_dir(ep_addr);
@@ -666,8 +668,9 @@ bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t
 // bytes should be written and second to keep the return value free to give back a boolean
 // success message. If total_bytes is too big, the FIFO will copy only what is available
 // into the USB buffer!
-bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
   uint8_t const epnum = tu_edpt_number(ep_addr);
   uint8_t const dir   = tu_edpt_dir(ep_addr);
diff --git a/src/portable/mindmotion/mm32/dcd_mm32f327x_otg.c b/src/portable/mindmotion/mm32/dcd_mm32f327x_otg.c
index 1ce3da27e..5cec4defb 100644
--- a/src/portable/mindmotion/mm32/dcd_mm32f327x_otg.c
+++ b/src/portable/mindmotion/mm32/dcd_mm32f327x_otg.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -282,7 +283,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
   (void) rhport;
   _dcd.addr = dev_addr & 0x7F;
   /* Response with status first before changing device address */
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 }
 
 #ifdef __GNUC__ // caused by extra declaration of SystemCoreClock in freeRTOSConfig.h
@@ -381,8 +382,9 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr)
   bd->head            = 0;
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
   NVIC_DisableIRQ(USB_FS_IRQn);
   const unsigned epn = ep_addr & 0xFu;
diff --git a/src/portable/nordic/nrf5x/dcd_nrf5x.c b/src/portable/nordic/nrf5x/dcd_nrf5x.c
index 9e5f5117f..a2d634fe6 100644
--- a/src/portable/nordic/nrf5x/dcd_nrf5x.c
+++ b/src/portable/nordic/nrf5x/dcd_nrf5x.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -426,7 +427,8 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr) {
   __DSB();
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes) {
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   (void) rhport;
 
   uint8_t const epnum = tu_edpt_number(ep_addr);
diff --git a/src/portable/nuvoton/nuc120/dcd_nuc120.c b/src/portable/nuvoton/nuc120/dcd_nuc120.c
index 0edebf159..bb1d11355 100644
--- a/src/portable/nuvoton/nuc120/dcd_nuc120.c
+++ b/src/portable/nuvoton/nuc120/dcd_nuc120.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -294,8 +295,9 @@ void dcd_edpt_close_all (uint8_t rhport)
   // TODO implement dcd_edpt_close_all()
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   /* mine the data for the information we need */
@@ -326,8 +328,9 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t to
 }
 
 #if 0 // TODO support dcd_edpt_xfer_fifo API
-bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   /* mine the data for the information we need */
diff --git a/src/portable/nuvoton/nuc121/dcd_nuc121.c b/src/portable/nuvoton/nuc121/dcd_nuc121.c
index 37210ea34..067d455c6 100644
--- a/src/portable/nuvoton/nuc121/dcd_nuc121.c
+++ b/src/portable/nuvoton/nuc121/dcd_nuc121.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -323,8 +324,9 @@ void dcd_edpt_close_all (uint8_t rhport)
   // TODO implement dcd_edpt_close_all()
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   /* mine the data for the information we need */
@@ -355,8 +357,9 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t to
 }
 
 #if 0 // TODO support dcd_edpt_xfer_fifo API
-bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   /* mine the data for the information we need */
diff --git a/src/portable/nuvoton/nuc505/dcd_nuc505.c b/src/portable/nuvoton/nuc505/dcd_nuc505.c
index fa457d861..f7593cf25 100644
--- a/src/portable/nuvoton/nuc505/dcd_nuc505.c
+++ b/src/portable/nuvoton/nuc505/dcd_nuc505.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -376,8 +377,9 @@ void dcd_edpt_close_all (uint8_t rhport)
   // TODO implement dcd_edpt_close_all()
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   if (0x80 == ep_addr) /* control EP0 IN */
@@ -437,8 +439,9 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t to
 }
 
 #if 0 // TODO support dcd_edpt_xfer_fifo API
-bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   TU_ASSERT(0x80 != ep_addr && 0x00 != ep_addr);  // Must not be used for control stuff
diff --git a/src/portable/nxp/khci/dcd_khci.c b/src/portable/nxp/khci/dcd_khci.c
index 3d5e195a9..395bf0d3d 100644
--- a/src/portable/nxp/khci/dcd_khci.c
+++ b/src/portable/nxp/khci/dcd_khci.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -314,7 +315,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
 {
   _dcd.addr = dev_addr & 0x7F;
   /* Response with status first before changing device address */
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 }
 
 void dcd_remote_wakeup(uint8_t rhport)
@@ -428,8 +429,9 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr)
   if (ie) NVIC_EnableIRQ(USB0_IRQn);
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
   const unsigned epn      = tu_edpt_number(ep_addr);
   const unsigned dir      = tu_edpt_dir(ep_addr);
diff --git a/src/portable/nxp/lpc17_40/dcd_lpc17_40.c b/src/portable/nxp/lpc17_40/dcd_lpc17_40.c
index 855c59cd1..81220e850 100644
--- a/src/portable/nxp/lpc17_40/dcd_lpc17_40.c
+++ b/src/portable/nxp/lpc17_40/dcd_lpc17_40.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -205,7 +206,7 @@ void dcd_int_disable(uint8_t rhport)
 void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
 {
   // Response with status first before changing device address
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 
   sie_write(SIE_CMDCODE_SET_ADDRESS, 1, 0x80 | dev_addr); // 7th bit is : device_enable
 
@@ -399,8 +400,9 @@ static bool control_xact(uint8_t rhport, uint8_t dir, uint8_t * buffer, uint8_t
   return true;
 }
 
-bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   // Control transfer is not DMA support, and must be done in slave mode
   if ( tu_edpt_number(ep_addr) == 0 )
   {
diff --git a/src/portable/nxp/lpc_ip3511/dcd_lpc_ip3511.c b/src/portable/nxp/lpc_ip3511/dcd_lpc_ip3511.c
index 7c637ce0c..6e889b473 100644
--- a/src/portable/nxp/lpc_ip3511/dcd_lpc_ip3511.c
+++ b/src/portable/nxp/lpc_ip3511/dcd_lpc_ip3511.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -322,7 +323,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
   dcd_registers_t* dcd_reg = _dcd_controller[rhport].regs;
 
   // Response with status first before changing device address
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 
   dcd_reg->DEVCMDSTAT &= ~DEVCMDSTAT_DEVICE_ADDR_MASK;
   dcd_reg->DEVCMDSTAT |= dev_addr;
@@ -464,7 +465,8 @@ static void prepare_ep_xfer(uint8_t rhport, uint8_t ep_id, uint16_t buf_offset,
   ep_cs[0].cmd_sts.active = 1;
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes) {
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   uint8_t const ep_id = ep_addr2id(ep_addr);
 
   if (!buffer || total_bytes == 0) {
@@ -486,6 +488,7 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t to
 //--------------------------------------------------------------------+
 static void bus_reset(uint8_t rhport)
 {
+  (void) is_isr;
   tu_memclr(&_dcd, sizeof(dcd_data_t));
   edpt_reset_all(rhport);
 
diff --git a/src/portable/raspberrypi/pio_usb/dcd_pio_usb.c b/src/portable/raspberrypi/pio_usb/dcd_pio_usb.c
index 60afbd435..3653544d9 100644
--- a/src/portable/raspberrypi/pio_usb/dcd_pio_usb.c
+++ b/src/portable/raspberrypi/pio_usb/dcd_pio_usb.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -76,7 +77,7 @@ void dcd_set_address (uint8_t rhport, uint8_t dev_addr)
 {
   // must be called before queuing status
   pio_usb_device_set_address(dev_addr);
-  dcd_edpt_xfer(rhport, 0x80, NULL, 0);
+  dcd_edpt_xfer(rhport, 0x80, NULL, 0, false);
 }
 
 // Wake up host
@@ -114,15 +115,16 @@ void dcd_edpt_close_all (uint8_t rhport)
 }
 
 // Submit a transfer, When complete dcd_event_xfer_complete() is invoked to notify the stack
-bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
   endpoint_t *ep = pio_usb_device_get_endpoint_by_address(ep_addr);
   return pio_usb_ll_transfer_start(ep, buffer, total_bytes);
 }
 
 // Submit a transfer where is managed by FIFO, When complete dcd_event_xfer_complete() is invoked to notify the stack - optional, however, must be listed in usbd.c
-//bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+//bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 //{
 //  (void) rhport;
 //  (void) ep_addr;
diff --git a/src/portable/raspberrypi/rp2040/dcd_rp2040.c b/src/portable/raspberrypi/rp2040/dcd_rp2040.c
index a89c2f42b..0a7c250c2 100644
--- a/src/portable/raspberrypi/rp2040/dcd_rp2040.c
+++ b/src/portable/raspberrypi/rp2040/dcd_rp2040.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -526,7 +527,8 @@ void dcd_edpt_close_all(uint8_t rhport) {
   reset_non_control_endpoints();
 }
 
-bool dcd_edpt_xfer(__unused uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes) {
+bool dcd_edpt_xfer(__unused uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   assert(rhport == 0);
   hw_endpoint_xfer(ep_addr, buffer, total_bytes);
   return true;
diff --git a/src/portable/renesas/rusb2/dcd_rusb2.c b/src/portable/renesas/rusb2/dcd_rusb2.c
index ecd28973c..9b875f0d1 100644
--- a/src/portable/renesas/rusb2/dcd_rusb2.c
+++ b/src/portable/renesas/rusb2/dcd_rusb2.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -859,8 +860,9 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr)
   _dcd.ep[dir][epn] = 0;
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   rusb2_reg_t* rusb = RUSB2_REG(rhport);
 
   dcd_int_disable(rhport);
@@ -870,8 +872,9 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t to
   return r;
 }
 
-bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   // USB buffers always work in bytes so to avoid unnecessary divisions we demand item_size = 1
   TU_ASSERT(ff->item_size == 1);
   rusb2_reg_t* rusb = RUSB2_REG(rhport);
diff --git a/src/portable/sony/cxd56/dcd_cxd56.c b/src/portable/sony/cxd56/dcd_cxd56.c
index a13cd152c..664952b83 100644
--- a/src/portable/sony/cxd56/dcd_cxd56.c
+++ b/src/portable/sony/cxd56/dcd_cxd56.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -358,8 +359,9 @@ void dcd_edpt_close_all (uint8_t rhport)
   // TODO implement dcd_edpt_close_all()
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   bool ret = true;
diff --git a/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c b/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
index ed823a832..640481442 100644
--- a/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
+++ b/src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -246,7 +247,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr) {
   (void)dev_addr;
 
   // Respond with status
-  dcd_edpt_xfer(rhport, TUSB_DIR_IN_MASK | 0x00, NULL, 0);
+  dcd_edpt_xfer(rhport, TUSB_DIR_IN_MASK | 0x00, NULL, 0, false);
 
   // DCD can only set address after status for this request is complete.
   // do it at dcd_edpt0_status_complete()
@@ -788,7 +789,8 @@ static bool edpt_xfer(uint8_t rhport, uint8_t ep_num, tusb_dir_t dir) {
   return true;
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t total_bytes) {
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   uint8_t const ep_num = tu_edpt_number(ep_addr);
   tusb_dir_t const dir = tu_edpt_dir(ep_addr);
   xfer_ctl_t *xfer = xfer_ctl_ptr(ep_num, dir);
@@ -801,7 +803,8 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t *buffer, uint16_t to
   return edpt_xfer(rhport, ep_num, dir);
 }
 
-bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t *ff, uint16_t total_bytes) {
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   uint8_t const ep_num = tu_edpt_number(ep_addr);
   tusb_dir_t const dir = tu_edpt_dir(ep_addr);
   xfer_ctl_t *xfer = xfer_ctl_ptr(ep_num, dir);
diff --git a/src/portable/sunxi/dcd_sunxi_musb.c b/src/portable/sunxi/dcd_sunxi_musb.c
index f1f4897cb..52d69ad01 100644
--- a/src/portable/sunxi/dcd_sunxi_musb.c
+++ b/src/portable/sunxi/dcd_sunxi_musb.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -1083,8 +1084,9 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr)
 }
 
 // Submit a transfer, When complete dcd_event_xfer_complete() is invoked to notify the stack
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void)rhport;
   bool ret;
   // TU_LOG1("X %x %d\r\n", ep_addr, total_bytes);
@@ -1102,8 +1104,9 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t t
 }
 
 // Submit a transfer where is managed by FIFO, When complete dcd_event_xfer_complete() is invoked to notify the stack - optional, however, must be listed in usbd.c
-bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void)rhport;
   bool ret;
   // TU_LOG1("X %x %d\r\n", ep_addr, total_bytes);
diff --git a/src/portable/synopsys/dwc2/dcd_dwc2.c b/src/portable/synopsys/dwc2/dcd_dwc2.c
index f1e4dbd77..f3a0ee7fc 100644
--- a/src/portable/synopsys/dwc2/dcd_dwc2.c
+++ b/src/portable/synopsys/dwc2/dcd_dwc2.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -456,7 +457,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr) {
   dwc2->dcfg = (dwc2->dcfg & ~DCFG_DAD_Msk) | (dev_addr << DCFG_DAD_Pos);
 
   // Response with status after changing device address
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false, false);
 }
 
 void dcd_remote_wakeup(uint8_t rhport) {
@@ -577,13 +578,14 @@ bool dcd_edpt_iso_activate(uint8_t rhport,  tusb_desc_endpoint_t const * p_endpo
   return true;
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes) {
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   uint8_t const epnum = tu_edpt_number(ep_addr);
   uint8_t const dir = tu_edpt_dir(ep_addr);
   xfer_ctl_t* xfer = XFER_CTL_BASE(epnum, dir);
   bool ret;
 
-  usbd_spin_lock(false);
+  usbd_spin_lock(is_isr);
 
   if (xfer->max_size == 0) {
     ret = false;  // Endpoint is closed
@@ -602,7 +604,7 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t to
     ret = true;
   }
 
-  usbd_spin_unlock(false);
+  usbd_spin_unlock(is_isr);
 
   return ret;
 }
@@ -611,7 +613,8 @@ bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t to
 // bytes should be written and second to keep the return value free to give back a boolean
 // success message. If total_bytes is too big, the FIFO will copy only what is available
 // into the USB buffer!
-bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t* ff, uint16_t total_bytes) {
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t* ff, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   // USB buffers always work in bytes so to avoid unnecessary divisions we demand item_size = 1
   TU_ASSERT(ff->item_size == 1);
 
@@ -620,7 +623,7 @@ bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t* ff, uint16_t
   xfer_ctl_t* xfer = XFER_CTL_BASE(epnum, dir);
   bool ret;
 
-  usbd_spin_lock(false);
+  usbd_spin_lock(is_isr);
 
   if (xfer->max_size == 0) {
     ret = false;  // Endpoint is closed
@@ -635,7 +638,7 @@ bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t* ff, uint16_t
     ret = true;
   }
 
-  usbd_spin_unlock(false);
+  usbd_spin_unlock(is_isr);
 
   return ret;
 }
diff --git a/src/portable/template/dcd_template.c b/src/portable/template/dcd_template.c
index 3738ac0cb..ff7995c11 100644
--- a/src/portable/template/dcd_template.c
+++ b/src/portable/template/dcd_template.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -113,7 +114,8 @@ void dcd_edpt_close_all (uint8_t rhport) {
 }
 
 // Submit a transfer, When complete dcd_event_xfer_complete() is invoked to notify the stack
-bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes) {
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   (void) rhport;
   (void) ep_addr;
   (void) buffer;
@@ -122,7 +124,8 @@ bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t
 }
 
 // Submit a transfer where is managed by FIFO, When complete dcd_event_xfer_complete() is invoked to notify the stack - optional, however, must be listed in usbd.c
-bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes) {
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   (void) rhport;
   (void) ep_addr;
   (void) ff;
diff --git a/src/portable/ti/msp430x5xx/dcd_msp430x5xx.c b/src/portable/ti/msp430x5xx/dcd_msp430x5xx.c
index 64cbc5087..def55b59b 100644
--- a/src/portable/ti/msp430x5xx/dcd_msp430x5xx.c
+++ b/src/portable/ti/msp430x5xx/dcd_msp430x5xx.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -219,7 +220,7 @@ void dcd_set_address (uint8_t rhport, uint8_t dev_addr)
   USBFUNADR = dev_addr;
 
   // Response with status after changing device address
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 }
 
 void dcd_remote_wakeup(uint8_t rhport)
@@ -344,8 +345,9 @@ void dcd_edpt_close_all (uint8_t rhport)
   // TODO implement dcd_edpt_close_all()
 }
 
-bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   uint8_t const epnum = tu_edpt_number(ep_addr);
@@ -393,8 +395,9 @@ bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t
 }
 
 #if 0 // TODO support dcd_edpt_xfer_fifo API
-bool dcd_edpt_xfer_fifo (uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes)
+bool dcd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t * ff, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void) rhport;
 
   uint8_t const epnum = tu_edpt_number(ep_addr);
diff --git a/src/portable/valentyusb/eptri/dcd_eptri.c b/src/portable/valentyusb/eptri/dcd_eptri.c
index a03c94558..a389aa761 100644
--- a/src/portable/valentyusb/eptri/dcd_eptri.c
+++ b/src/portable/valentyusb/eptri/dcd_eptri.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -375,7 +376,7 @@ void dcd_int_disable(uint8_t rhport)
 void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
 {
   // Respond with ACK status first before changing device address
-  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0);
+  dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_IN), NULL, 0, false);
 
   // Wait for the response packet to get sent
   while (tx_active)
@@ -475,8 +476,9 @@ void dcd_edpt_clear_stall(uint8_t rhport, uint8_t ep_addr)
   // IN endpoints will get un-stalled when more data is written.
 }
 
-bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr)
 {
+  (void) is_isr;
   (void)rhport;
   uint8_t ep_num = tu_edpt_number(ep_addr);
   uint8_t ep_dir = tu_edpt_dir(ep_addr);
diff --git a/src/portable/wch/dcd_ch32_usbfs.c b/src/portable/wch/dcd_ch32_usbfs.c
index c248ba14e..c5b610b82 100644
--- a/src/portable/wch/dcd_ch32_usbfs.c
+++ b/src/portable/wch/dcd_ch32_usbfs.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -218,7 +219,7 @@ void dcd_int_disable(uint8_t rhport) {
 
 void dcd_set_address(uint8_t rhport, uint8_t dev_addr) {
   (void) dev_addr;
-  dcd_edpt_xfer(rhport, 0x80, NULL, 0); // zlp status response
+  dcd_edpt_xfer(rhport, 0x80, NULL, 0, false); // zlp status response
 }
 
 void dcd_remote_wakeup(uint8_t rhport) {
@@ -289,7 +290,8 @@ void dcd_edpt_close(uint8_t rhport, uint8_t ep_addr) {
   // TODO optional
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes) {
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   (void) rhport;
   uint8_t ep = tu_edpt_number(ep_addr);
   uint8_t dir = tu_edpt_dir(ep_addr);
diff --git a/src/portable/wch/dcd_ch32_usbhs.c b/src/portable/wch/dcd_ch32_usbhs.c
index 4a208b9df..cf2deab78 100644
--- a/src/portable/wch/dcd_ch32_usbhs.c
+++ b/src/portable/wch/dcd_ch32_usbhs.c
@@ -1,3 +1,4 @@
+
 /*
  * The MIT License (MIT)
  *
@@ -203,7 +204,7 @@ void dcd_set_address(uint8_t rhport, uint8_t dev_addr) {
   (void) dev_addr;
 
   // Response with zlp status
-  dcd_edpt_xfer(rhport, 0x80, NULL, 0);
+  dcd_edpt_xfer(rhport, 0x80, NULL, 0, false);
 }
 
 void dcd_remote_wakeup(uint8_t rhport) {
@@ -315,7 +316,8 @@ void dcd_edpt_clear_stall(uint8_t rhport, uint8_t ep_addr) {
   }
 }
 
-bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes) {
+bool dcd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t * buffer, uint16_t total_bytes, bool is_isr) {
+  (void) is_isr;
   (void) rhport;
   uint8_t const ep_num = tu_edpt_number(ep_addr);
   tusb_dir_t const dir = tu_edpt_dir(ep_addr);
diff --git a/test/unit-test/test/device/msc/test_msc_device.c b/test/unit-test/test/device/msc/test_msc_device.c
index 49843a921..ea02b7050 100644
--- a/test/unit-test/test/device/msc/test_msc_device.c
+++ b/test/unit-test/test/device/msc/test_msc_device.c
@@ -256,7 +256,7 @@ void test_msc(void)
   dcd_edpt_open_ExpectAndReturn(rhport, (tusb_desc_endpoint_t const *) tu_desc_next(desc_ep), true);
 
   // Prepare SCSI command
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_MSC_OUT, NULL, sizeof(msc_cbw_t), true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_MSC_OUT, NULL, sizeof(msc_cbw_t), false, true);
   dcd_edpt_xfer_IgnoreArg_buffer();
   dcd_edpt_xfer_ReturnMemThruPtr_buffer( (uint8_t*) &cbw_read10, sizeof(msc_cbw_t));
 
@@ -264,20 +264,20 @@ void test_msc(void)
   dcd_event_xfer_complete(rhport, EDPT_MSC_OUT, sizeof(msc_cbw_t), 0, true);
 
   // control status
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_IN, NULL, 0, true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_IN, NULL, 0, false, true);
 
   // SCSI Data transfer
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_MSC_IN, NULL, 512, true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_MSC_IN, NULL, 512, false, true);
   dcd_edpt_xfer_IgnoreArg_buffer();
   dcd_event_xfer_complete(rhport, EDPT_MSC_IN, 512, 0, true); // complete
 
   // SCSI Status
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_MSC_IN, NULL, 13, true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_MSC_IN, NULL, 13, false, true);
   dcd_edpt_xfer_IgnoreArg_buffer();
   dcd_event_xfer_complete(rhport, EDPT_MSC_IN, 13, 0, true);
 
   // Prepare for next command
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_MSC_OUT, NULL, sizeof(msc_cbw_t), true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_MSC_OUT, NULL, sizeof(msc_cbw_t), false, true);
   dcd_edpt_xfer_IgnoreArg_buffer();
 
   tud_task();
diff --git a/test/unit-test/test/device/usbd/test_usbd.c b/test/unit-test/test/device/usbd/test_usbd.c
index f0153da3f..3a2cf3217 100644
--- a/test/unit-test/test/device/usbd/test_usbd.c
+++ b/test/unit-test/test/device/usbd/test_usbd.c
@@ -151,11 +151,11 @@ void test_usbd_get_device_descriptor(void)
   dcd_event_setup_received(rhport, (uint8_t*) &req_get_desc_device, false);
 
   // data
-  dcd_edpt_xfer_ExpectWithArrayAndReturn(rhport, 0x80, (uint8_t*)&data_desc_device, sizeof(tusb_desc_device_t), sizeof(tusb_desc_device_t), true);
+  dcd_edpt_xfer_ExpectWithArrayAndReturn(rhport, 0x80, (uint8_t*)&data_desc_device, sizeof(tusb_desc_device_t), sizeof(tusb_desc_device_t), false, true);
   dcd_event_xfer_complete(rhport, EDPT_CTRL_IN, sizeof(tusb_desc_device_t), 0, false);
 
   // status
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_OUT, NULL, 0, true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_OUT, NULL, 0, false, true);
   dcd_event_xfer_complete(rhport, EDPT_CTRL_OUT, 0, 0, false);
   dcd_edpt0_status_complete_ExpectWithArray(rhport, &req_get_desc_device, 1);
 
@@ -184,11 +184,11 @@ void test_usbd_get_configuration_descriptor(void)
   dcd_event_setup_received(rhport, (uint8_t*) &req_get_desc_configuration, false);
 
   // data
-  dcd_edpt_xfer_ExpectWithArrayAndReturn(rhport, 0x80, (uint8_t*) data_desc_configuration, total_len, total_len, true);
+  dcd_edpt_xfer_ExpectWithArrayAndReturn(rhport, 0x80, (uint8_t*) data_desc_configuration, total_len, total_len, false, true);
   dcd_event_xfer_complete(rhport, EDPT_CTRL_IN, total_len, 0, false);
 
   // status
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_OUT, NULL, 0, true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_OUT, NULL, 0, false, true);
   dcd_event_xfer_complete(rhport, EDPT_CTRL_OUT, 0, 0, false);
   dcd_edpt0_status_complete_ExpectWithArray(rhport, &req_get_desc_configuration, 1);
 
@@ -227,20 +227,20 @@ void test_usbd_control_in_zlp(void)
 
   // 1st transaction
   dcd_edpt_xfer_ExpectWithArrayAndReturn(rhport, EDPT_CTRL_IN,
-                                         zlp_desc_configuration, CFG_TUD_ENDPOINT0_SIZE, CFG_TUD_ENDPOINT0_SIZE, true);
+                                         zlp_desc_configuration, CFG_TUD_ENDPOINT0_SIZE, CFG_TUD_ENDPOINT0_SIZE, false, true);
   dcd_event_xfer_complete(rhport, EDPT_CTRL_IN, CFG_TUD_ENDPOINT0_SIZE, 0, false);
 
   // 2nd transaction
   dcd_edpt_xfer_ExpectWithArrayAndReturn(rhport, EDPT_CTRL_IN,
-                                         zlp_desc_configuration + CFG_TUD_ENDPOINT0_SIZE, CFG_TUD_ENDPOINT0_SIZE, CFG_TUD_ENDPOINT0_SIZE, true);
+                                         zlp_desc_configuration + CFG_TUD_ENDPOINT0_SIZE, CFG_TUD_ENDPOINT0_SIZE, CFG_TUD_ENDPOINT0_SIZE, false, true);
   dcd_event_xfer_complete(rhport, EDPT_CTRL_IN, CFG_TUD_ENDPOINT0_SIZE, 0, false);
 
   // Expect Zero length Packet
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_IN, NULL, 0, true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_IN, NULL, 0, false, true);
   dcd_event_xfer_complete(rhport, EDPT_CTRL_IN, 0, 0, false);
 
   // Status
-  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_OUT, NULL, 0, true);
+  dcd_edpt_xfer_ExpectAndReturn(rhport, EDPT_CTRL_OUT, NULL, 0, false, true);
   dcd_event_xfer_complete(rhport, EDPT_CTRL_OUT, 0, 0, false);
   dcd_edpt0_status_complete_ExpectWithArray(rhport, &req_get_desc_configuration, 1);