STM32L476 USB HAL errors Topic is solved

[kreyl]

MCU: stm32L476RC
OS: Chibios v16.1.5, RT kernel
USB: only D+ and D- connected

Generally, it seems that USB OTG in L476 is more like one in F7xx MCU, but HAL uses something like F4xx.

1) Max Endpoints count set to 3; ref man says 5 (usb_lld.h line 153; ref man p.1504)
2) usb_lld_connect_bus (usb_lld.h line 506) sets GCCFG_VBUSBSEN; there is no such bit in GCCFG (ref man p. 1551) => no connection occurs.
Same with usb_lld_disconnect_bus (usb_lld.h line 517)

When I clear DCTL_SDIS bit (like in F7xx MCU), - connection occurs.
But still no good after that: after several good-looking IRQs (Suspend, Reset, EnumerationDone, RxFifoLvl) I have ep0 out irq, with no STUP bit in DOEPINT register (strange 0x8001 value in it). After that _usb_ep0out called, which results in "EP0 state machine error", as ep0 is in USB_EP0_WAITING_SETUP state.

[RoccoMarco]

Hi,
thanks for the feedback.We are working on it. A more recent version of code is on trunk but I am currently unable to make OTG working.

I have found some issues on clock init so I had to fix it before to proceed with OTG fixes.

Ciao,
RM

[kreyl]

Here is what I found this morning.
USB OTG module of L476 generates extra IRQs when SETUP packet is received.
First is RXFLVL with "SETUP data packet received" in pkt status.
Then OEP INT for EP0, saying there is OUT data (and here HAL halts, as EP0 is waiting SETUP data).
After that again RXFLVL - saying zero bytes received, with "SETUP transaction completed" in pkt status.
After that again OEP INT for EP0, saying there is SETUP data, finally.

All started to work when I disabled halting and stalling on EP0 state machine error at line 954 of usb.c. Therefore state machine just ignores state errors and, consequently, extra irqs.
Not a good method, though But I need a working prototype by monday, and have to use dirty solutions.

Hope this helps. Thank you!

[Giovanni]

Thanks for hints but we need to understand the root of the problem too.

At least we have a base to work on now.

Giovanni

[Giovanni]

Bumped.

[Giovanni]

Hi,

Finally fixed (bug #786).

It was caused by a different order in interrupts servicing on the L4, the transfer interrupt is triggered before the setup interrupt and this caused the problem.

The driver code has been modified to not depend on IRQ order, now it should be OK.

Thanks for the analysis, it helped a lot.

Giovanni

[lilvinz]

Hi Giovanni,

it seems i am hitting a similar issue but on the fixed version: svn://svn.code.sf.net/p/chibios/svn/bra ... 6.1.x@9890
_usb_ep0out() panics with "EP0 state machine error" while usbp->ep0state being USB_EP0_TX.
Commenting out the error handling "fixes" it for me as well.

Wireshark trace up to the panic looks like this:

Code: Select all

663   5.370454   host   2.0.0     USB   64   SET ADDRESS Request
664   5.370702   2.0.0   host     USB   64   SET ADDRESS Response
665   5.390448   host   2.117.0   USB   64   GET DESCRIPTOR Request DEVICE
666   5.390696   2.117.0   host   USB   82   GET DESCRIPTOR Response DEVICE
667   5.390724   host   2.117.0   USB   64   GET DESCRIPTOR Request DEVICE QUALIFIER
668   5.390970   2.117.0   host   USB   64   GET DESCRIPTOR Response DEVICE QUALIFIER[Malformed Packet]
669   5.390996   host   2.117.0   USB   64   GET DESCRIPTOR Request DEVICE QUALIFIER
670   5.391442   2.117.0   host   USB   64   GET DESCRIPTOR Response DEVICE QUALIFIER[Malformed Packet]
671   5.391460   host   2.117.0   USB   64   GET DESCRIPTOR Request DEVICE QUALIFIER
672   5.391815   2.117.0   host   USB   64   GET DESCRIPTOR Response DEVICE QUALIFIER[Malformed Packet]
673   5.391845   host   2.117.0   USB   64   GET DESCRIPTOR Request CONFIGURATION
674   5.392190   2.117.0   host   USB   64   GET DESCRIPTOR Response CONFIGURATION[Malformed Packet]
675   5.392204   host   2.117.0   USB   64   GET DESCRIPTOR Request CONFIGURATION


Kernel messages from host:

Code: Select all

[4660715.323138] usb 2-1.7.3.1: new full-speed USB device number 117 using ehci-pci
[4660720.415568] usb 2-1.7.3.1: unable to read config index 0 descriptor/start: -110
[4660720.415577] usb 2-1.7.3.1: can't read configurations, error -110
[4660720.491333] usb 2-1.7.3.1: new full-speed USB device number 118 using ehci-pci
[4660725.563534] usb 2-1.7.3.1: device descriptor read/64, error -110


What information is required to further trace that issue down?

Cheers

Vinz

PS: STM32L476 on custom board, gcc arm embedded 5.4 2016q3

[Giovanni]

hi,

I need to be able to debug, a list of steps in order to reproduce the issue.

Giovanni

[lilvinz]

Up to now i have not been able to strip this down to a simple example.
It seems to depend on timing.
The issue is still present and i am still trying.

Cheers

Vinz

[lilvinz]

Hi Giovanni,

finally i found some time to reproduce the issue using a demo.

Apply the following patch to svn://svn.code.sf.net/p/chibios/svn/trunk@9991 which basically adds usb serial device to the stm32l476 demo and enables debug asserts:

Code: Select all

diff --git a/demos/STM32/RT-STM32L476-DISCOVERY/Makefile b/demos/STM32/RT-STM32L476-DISCOVERY/Makefile
index 7b092d0..9354336 100644
--- a/demos/STM32/RT-STM32L476-DISCOVERY/Makefile
+++ b/demos/STM32/RT-STM32L476-DISCOVERY/Makefile
@@ -113,7 +113,7 @@ CSRC = $(STARTUPSRC) \
        $(PLATFORMSRC) \
        $(BOARDSRC) \
        $(TESTSRC) \
-       main.c
+       main.c usbcfg.c
 
 # C++ sources that can be compiled in ARM or THUMB mode depending on the global
 # setting.
diff --git a/demos/STM32/RT-STM32L476-DISCOVERY/chconf.h b/demos/STM32/RT-STM32L476-DISCOVERY/chconf.h
index ad6b53a..4e64ef1 100644
--- a/demos/STM32/RT-STM32L476-DISCOVERY/chconf.h
+++ b/demos/STM32/RT-STM32L476-DISCOVERY/chconf.h
@@ -347,7 +347,7 @@
  *
  * @note    The default is @p FALSE.
  */
-#define CH_DBG_ENABLE_ASSERTS               FALSE
+#define CH_DBG_ENABLE_ASSERTS               TRUE
 
 /**
  * @brief   Debug option, trace buffer.
diff --git a/demos/STM32/RT-STM32L476-DISCOVERY/halconf.h b/demos/STM32/RT-STM32L476-DISCOVERY/halconf.h
index 82602b4..c843cbb 100644
--- a/demos/STM32/RT-STM32L476-DISCOVERY/halconf.h
+++ b/demos/STM32/RT-STM32L476-DISCOVERY/halconf.h
@@ -146,7 +146,7 @@
  * @brief   Enables the SERIAL over USB subsystem.
  */
 #if !defined(HAL_USE_SERIAL_USB) || defined(__DOXYGEN__)
-#define HAL_USE_SERIAL_USB          FALSE
+#define HAL_USE_SERIAL_USB          TRUE
 #endif
 
 /**
@@ -167,7 +167,7 @@
  * @brief   Enables the USB subsystem.
  */
 #if !defined(HAL_USE_USB) || defined(__DOXYGEN__)
-#define HAL_USE_USB                 FALSE
+#define HAL_USE_USB                 TRUE
 #endif
 
 /**
diff --git a/demos/STM32/RT-STM32L476-DISCOVERY/main.c b/demos/STM32/RT-STM32L476-DISCOVERY/main.c
index 50fb1dc..520700a 100644
--- a/demos/STM32/RT-STM32L476-DISCOVERY/main.c
+++ b/demos/STM32/RT-STM32L476-DISCOVERY/main.c
@@ -18,6 +18,8 @@
 #include "hal.h"
 #include "ch_test.h"
 
+#include "usbcfg.h"
+
 /*
  * LEDs blinker thread, times are in milliseconds.
  */
@@ -54,6 +56,22 @@ int main(void) {
   chSysInit();
 
   /*
+   * Initializes a serial-over-USB CDC driver.
+   */
+  sduObjectInit(&SDU1);
+  sduStart(&SDU1, &serusbcfg);
+
+  /*
+   * Activates the USB driver and then the USB bus pull-up on D+.
+   * Note, a delay is inserted in order to not have to disconnect the cable
+   * after a reset.
+   */
+  usbDisconnectBus(serusbcfg.usbp);
+  chThdSleepMilliseconds(1500);
+  usbStart(serusbcfg.usbp, &usbcfg);
+  usbConnectBus(serusbcfg.usbp);
+
+  /*
    * Activates the serial driver 2 using the driver default configuration.
    */
   sdStart(&SD2, NULL);
@@ -69,7 +87,7 @@ int main(void) {
    */
   while (true) {
     if (palReadLine(LINE_JOY_CENTER))
-      test_execute((BaseSequentialStream *)&SD2);
+      test_execute((BaseSequentialStream *)&SDU1);
     chThdSleepMilliseconds(500);
   }
 }
diff --git a/demos/STM32/RT-STM32L476-DISCOVERY/mcuconf.h b/demos/STM32/RT-STM32L476-DISCOVERY/mcuconf.h
index 82560bc..f7774df 100644
--- a/demos/STM32/RT-STM32L476-DISCOVERY/mcuconf.h
+++ b/demos/STM32/RT-STM32L476-DISCOVERY/mcuconf.h
@@ -321,7 +321,7 @@
 /*
  * USB driver system settings.
  */
-#define STM32_USB_USE_OTG1                  FALSE
+#define STM32_USB_USE_OTG1                  TRUE
 #define STM32_USB_OTG1_IRQ_PRIORITY         14
 #define STM32_USB_OTG1_RX_FIFO_SIZE         512
 #define STM32_USB_OTG_THREAD_PRIO           LOWPRIO
diff --git a/demos/STM32/RT-STM32L476-DISCOVERY/patch b/demos/STM32/RT-STM32L476-DISCOVERY/patch
new file mode 100644
index 0000000..e69de29
diff --git a/demos/STM32/RT-STM32L476-DISCOVERY/usbcfg.c b/demos/STM32/RT-STM32L476-DISCOVERY/usbcfg.c
new file mode 100644
index 0000000..15a88ad
--- /dev/null
+++ b/demos/STM32/RT-STM32L476-DISCOVERY/usbcfg.c
@@ -0,0 +1,373 @@
+/*
+    ChibiOS - Copyright (C) 2006..2016 Giovanni Di Sirio
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+*/
+
+#include "hal.h"
+
+/* Virtual serial port over USB.*/
+SerialUSBDriver SDU1;
+
+/*
+ * Endpoints to be used for USBD1.
+ */
+#define USBD1_DATA_REQUEST_EP           1
+#define USBD1_DATA_AVAILABLE_EP         1
+#define USBD1_INTERRUPT_REQUEST_EP      2
+
+/*
+ * USB Device Descriptor.
+ */
+static const uint8_t vcom_device_descriptor_data[18] = {
+  USB_DESC_DEVICE       (0x0110,        /* bcdUSB (1.1).                    */
+                         0x02,          /* bDeviceClass (CDC).              */
+                         0x00,          /* bDeviceSubClass.                 */
+                         0x00,          /* bDeviceProtocol.                 */
+                         0x40,          /* bMaxPacketSize.                  */
+                         0x0483,        /* idVendor (ST).                   */
+                         0x5740,        /* idProduct.                       */
+                         0x0200,        /* bcdDevice.                       */
+                         1,             /* iManufacturer.                   */
+                         2,             /* iProduct.                        */
+                         3,             /* iSerialNumber.                   */
+                         1)             /* bNumConfigurations.              */
+};
+
+/*
+ * Device Descriptor wrapper.
+ */
+static const USBDescriptor vcom_device_descriptor = {
+  sizeof vcom_device_descriptor_data,
+  vcom_device_descriptor_data
+};
+
+/* Configuration Descriptor tree for a CDC.*/
+static const uint8_t vcom_configuration_descriptor_data[67] = {
+  /* Configuration Descriptor.*/
+  USB_DESC_CONFIGURATION(67,            /* wTotalLength.                    */
+                         0x02,          /* bNumInterfaces.                  */
+                         0x01,          /* bConfigurationValue.             */
+                         0,             /* iConfiguration.                  */
+                         0xC0,          /* bmAttributes (self powered).     */
+                         50),           /* bMaxPower (100mA).               */
+  /* Interface Descriptor.*/
+  USB_DESC_INTERFACE    (0x00,          /* bInterfaceNumber.                */
+                         0x00,          /* bAlternateSetting.               */
+                         0x01,          /* bNumEndpoints.                   */
+                         0x02,          /* bInterfaceClass (Communications
+                                           Interface Class, CDC section
+                                           4.2).                            */
+                         0x02,          /* bInterfaceSubClass (Abstract
+                                         Control Model, CDC section 4.3).   */
+                         0x01,          /* bInterfaceProtocol (AT commands,
+                                           CDC section 4.4).                */
+                         0),            /* iInterface.                      */
+  /* Header Functional Descriptor (CDC section 5.2.3).*/
+  USB_DESC_BYTE         (5),            /* bLength.                         */
+  USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
+  USB_DESC_BYTE         (0x00),         /* bDescriptorSubtype (Header
+                                           Functional Descriptor.           */
+  USB_DESC_BCD          (0x0110),       /* bcdCDC.                          */
+  /* Call Management Functional Descriptor. */
+  USB_DESC_BYTE         (5),            /* bFunctionLength.                 */
+  USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
+  USB_DESC_BYTE         (0x01),         /* bDescriptorSubtype (Call Management
+                                           Functional Descriptor).          */
+  USB_DESC_BYTE         (0x00),         /* bmCapabilities (D0+D1).          */
+  USB_DESC_BYTE         (0x01),         /* bDataInterface.                  */
+  /* ACM Functional Descriptor.*/
+  USB_DESC_BYTE         (4),            /* bFunctionLength.                 */
+  USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
+  USB_DESC_BYTE         (0x02),         /* bDescriptorSubtype (Abstract
+                                           Control Management Descriptor).  */
+  USB_DESC_BYTE         (0x02),         /* bmCapabilities.                  */
+  /* Union Functional Descriptor.*/
+  USB_DESC_BYTE         (5),            /* bFunctionLength.                 */
+  USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
+  USB_DESC_BYTE         (0x06),         /* bDescriptorSubtype (Union
+                                           Functional Descriptor).          */
+  USB_DESC_BYTE         (0x00),         /* bMasterInterface (Communication
+                                           Class Interface).                */
+  USB_DESC_BYTE         (0x01),         /* bSlaveInterface0 (Data Class
+                                           Interface).                      */
+  /* Endpoint 2 Descriptor.*/
+  USB_DESC_ENDPOINT     (USBD1_INTERRUPT_REQUEST_EP|0x80,
+                         0x03,          /* bmAttributes (Interrupt).        */
+                         0x0008,        /* wMaxPacketSize.                  */
+                         0xFF),         /* bInterval.                       */
+  /* Interface Descriptor.*/
+  USB_DESC_INTERFACE    (0x01,          /* bInterfaceNumber.                */
+                         0x00,          /* bAlternateSetting.               */
+                         0x02,          /* bNumEndpoints.                   */
+                         0x0A,          /* bInterfaceClass (Data Class
+                                           Interface, CDC section 4.5).     */
+                         0x00,          /* bInterfaceSubClass (CDC section
+                                           4.6).                            */
+                         0x00,          /* bInterfaceProtocol (CDC section
+                                           4.7).                            */
+                         0x00),         /* iInterface.                      */
+  /* Endpoint 3 Descriptor.*/
+  USB_DESC_ENDPOINT     (USBD1_DATA_AVAILABLE_EP,       /* bEndpointAddress.*/
+                         0x02,          /* bmAttributes (Bulk).             */
+                         0x0040,        /* wMaxPacketSize.                  */
+                         0x00),         /* bInterval.                       */
+  /* Endpoint 1 Descriptor.*/
+  USB_DESC_ENDPOINT     (USBD1_DATA_REQUEST_EP|0x80,    /* bEndpointAddress.*/
+                         0x02,          /* bmAttributes (Bulk).             */
+                         0x0040,        /* wMaxPacketSize.                  */
+                         0x00)          /* bInterval.                       */
+};
+
+/*
+ * Configuration Descriptor wrapper.
+ */
+static const USBDescriptor vcom_configuration_descriptor = {
+  sizeof vcom_configuration_descriptor_data,
+  vcom_configuration_descriptor_data
+};
+
+/*
+ * U.S. English language identifier.
+ */
+static const uint8_t vcom_string0[] = {
+  USB_DESC_BYTE(4),                     /* bLength.                         */
+  USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
+  USB_DESC_WORD(0x0409)                 /* wLANGID (U.S. English).          */
+};
+
+/*
+ * Vendor string.
+ */
+static const uint8_t vcom_string1[] = {
+  USB_DESC_BYTE(38),                    /* bLength.                         */
+  USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
+  'S', 0, 'T', 0, 'M', 0, 'i', 0, 'c', 0, 'r', 0, 'o', 0, 'e', 0,
+  'l', 0, 'e', 0, 'c', 0, 't', 0, 'r', 0, 'o', 0, 'n', 0, 'i', 0,
+  'c', 0, 's', 0
+};
+
+/*
+ * Device Description string.
+ */
+static const uint8_t vcom_string2[] = {
+  USB_DESC_BYTE(56),                    /* bLength.                         */
+  USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
+  'C', 0, 'h', 0, 'i', 0, 'b', 0, 'i', 0, 'O', 0, 'S', 0, '/', 0,
+  'R', 0, 'T', 0, ' ', 0, 'V', 0, 'i', 0, 'r', 0, 't', 0, 'u', 0,
+  'a', 0, 'l', 0, ' ', 0, 'C', 0, 'O', 0, 'M', 0, ' ', 0, 'P', 0,
+  'o', 0, 'r', 0, 't', 0
+};
+
+/*
+ * Serial Number string.
+ */
+static const uint8_t vcom_string3[] = {
+  USB_DESC_BYTE(8),                     /* bLength.                         */
+  USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
+  '0' + CH_KERNEL_MAJOR, 0,
+  '0' + CH_KERNEL_MINOR, 0,
+  '0' + CH_KERNEL_PATCH, 0
+};
+
+/*
+ * Strings wrappers array.
+ */
+static const USBDescriptor vcom_strings[] = {
+  {sizeof vcom_string0, vcom_string0},
+  {sizeof vcom_string1, vcom_string1},
+  {sizeof vcom_string2, vcom_string2},
+  {sizeof vcom_string3, vcom_string3}
+};
+
+/*
+ * Handles the GET_DESCRIPTOR callback. All required descriptors must be
+ * handled here.
+ */
+static const USBDescriptor *get_descriptor(USBDriver *usbp,
+                                           uint8_t dtype,
+                                           uint8_t dindex,
+                                           uint16_t lang) {
+
+  (void)usbp;
+  (void)lang;
+  switch (dtype) {
+  case USB_DESCRIPTOR_DEVICE:
+    return &vcom_device_descriptor;
+  case USB_DESCRIPTOR_CONFIGURATION:
+    return &vcom_configuration_descriptor;
+  case USB_DESCRIPTOR_STRING:
+    if (dindex < 4)
+      return &vcom_strings[dindex];
+  }
+  return NULL;
+}
+
+/**
+ * @brief   IN EP1 state.
+ */
+static USBInEndpointState ep1instate;
+
+/**
+ * @brief   OUT EP1 state.
+ */
+static USBOutEndpointState ep1outstate;
+
+/**
+ * @brief   EP1 initialization structure (both IN and OUT).
+ */
+static const USBEndpointConfig ep1config = {
+  USB_EP_MODE_TYPE_BULK,
+  NULL,
+  sduDataTransmitted,
+  sduDataReceived,
+  0x0040,
+  0x0040,
+  &ep1instate,
+  &ep1outstate,
+  2,
+  NULL
+};
+
+/**
+ * @brief   IN EP2 state.
+ */
+static USBInEndpointState ep2instate;
+
+/**
+ * @brief   EP2 initialization structure (IN only).
+ */
+static const USBEndpointConfig ep2config = {
+  USB_EP_MODE_TYPE_INTR,
+  NULL,
+  sduInterruptTransmitted,
+  NULL,
+  0x0010,
+  0x0000,
+  &ep2instate,
+  NULL,
+  1,
+  NULL
+};
+
+/*
+ * Handles the USB driver global events.
+ */
+static void usb_event(USBDriver *usbp, usbevent_t event) {
+  extern SerialUSBDriver SDU1;
+
+  switch (event) {
+  case USB_EVENT_ADDRESS:
+    return;
+  case USB_EVENT_CONFIGURED:
+    chSysLockFromISR();
+
+    /* Enables the endpoints specified into the configuration.
+       Note, this callback is invoked from an ISR so I-Class functions
+       must be used.*/
+    usbInitEndpointI(usbp, USBD1_DATA_REQUEST_EP, &ep1config);
+    usbInitEndpointI(usbp, USBD1_INTERRUPT_REQUEST_EP, &ep2config);
+
+    /* Resetting the state of the CDC subsystem.*/
+    sduConfigureHookI(&SDU1);
+
+    chSysUnlockFromISR();
+    return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
+  case USB_EVENT_UNCONFIGURED:
+    /* Falls into.*/
+  case USB_EVENT_SUSPEND:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduSuspendHookI(&SDU1);
+
+    chSysUnlockFromISR();
+    return;
+  case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
+    return;
+  case USB_EVENT_STALLED:
+    return;
+  }
+  return;
+ 
+  switch (event)
+  {
+  case USB_EVENT_RESET:
+      return;
+  case USB_EVENT_ADDRESS:
+      return;
+  case USB_EVENT_CONFIGURED:
+       chSysLockFromISR();
+
+       /* Enables the endpoints specified into the configuration.
+          Note, this callback is invoked from an ISR so I-Class functions
+          must be used.*/
+       usbInitEndpointI(usbp, USBD1_DATA_REQUEST_EP, &ep1config);
+       usbInitEndpointI(usbp, USBD1_INTERRUPT_REQUEST_EP, &ep2config);
+
+       /* Resetting the state of the CDC subsystem.*/
+       sduConfigureHookI(&SDU1);
+
+       chSysUnlockFromISR();
+      return;
+  case USB_EVENT_UNCONFIGURED:
+      return;
+  case USB_EVENT_SUSPEND:
+      return;
+  case USB_EVENT_WAKEUP:
+      return;
+  case USB_EVENT_STALLED:
+      return;
+  }
+  return;
+}
+
+/*
+ * Handles the USB driver global events.
+ */
+static void sof_handler(USBDriver *usbp) {
+
+  (void)usbp;
+
+  osalSysLockFromISR();
+  sduSOFHookI(&SDU1);
+  osalSysUnlockFromISR();
+}
+
+/*
+ * USB driver configuration.
+ */
+const USBConfig usbcfg = {
+  usb_event,
+  get_descriptor,
+  sduRequestsHook,
+  sof_handler
+};
+
+/*
+ * Serial over USB driver configuration.
+ */
+const SerialUSBConfig serusbcfg = {
+  &USBD1,
+  USBD1_DATA_REQUEST_EP,
+  USBD1_DATA_AVAILABLE_EP,
+  USBD1_INTERRUPT_REQUEST_EP
+};
diff --git a/demos/STM32/RT-STM32L476-DISCOVERY/usbcfg.h b/demos/STM32/RT-STM32L476-DISCOVERY/usbcfg.h
new file mode 100644
index 0000000..b62a028
--- /dev/null
+++ b/demos/STM32/RT-STM32L476-DISCOVERY/usbcfg.h
@@ -0,0 +1,26 @@
+/*
+    ChibiOS - Copyright (C) 2006..2016 Giovanni Di Sirio
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+*/
+
+#ifndef USBCFG_H
+#define USBCFG_H
+
+extern const USBConfig usbcfg;
+extern SerialUSBConfig serusbcfg;
+extern SerialUSBDriver SDU1;
+
+#endif  /* USBCFG_H */
+
+/** @} */


Load the resulting image to a discoveryl476 board and connect the user usb to a host.
After the usb handshake has finished, the target will hang like this:

Code: Select all

#0  0x08008890 in chSysHalt (reason=<synthetic pointer>) at ../../../os/rt/src/chsys.c:200
#1  _usb_ep0out (usbp=0x20001238 <USBD1>, ep=0 '\000') at ../../../os/hal/src/hal_usb.c:951
#2  0x080084ca in usb_lld_serve_interrupt (usbp=<optimized out>) at ../../../os/hal/ports/STM32/LLD/OTGv1/hal_usb_lld.c:621
#3  Vector14C () at ../../../os/hal/ports/STM32/LLD/OTGv1/hal_usb_lld.c:651


osalDbgAssert(false, "EP0 state machine error"); in _usb_ep0out triggers.

Code: Select all

$ arm-none-eabi-gcc --version
arm-none-eabi-gcc (GNU Tools for ARM Embedded Processors) 5.4.1 20160919 (release) [ARM/embedded-5-branch revision 240496]


I hope this is sufficient for you to reproduce the issue.

Cheers

Vinz