Tentative USB suspend fix.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@9898 35acf78f-673a-0410-8e92-d51de3d6d3f4

demos/AVR/RT-ARDUINOLEONARDO/usbcfg.c

@@ -283,8 +283,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -302,17 +300,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/AVR/RT-PRO_MICRO/usbcfg.c

@@ -282,8 +282,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -301,17 +299,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/AVR/RT-TEENSY2-USB/usbcfg.c

@@ -248,8 +248,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -267,17 +265,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/STM32/RT-STM32F103-MAPLEMINI/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/STM32/RT-STM32F103-STM3210E_EVAL-FATFS-USB/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/STM32/RT-STM32F103_INEMO_DISCOVERY/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/STM32/RT-STM32F407-OLIMEX_E407-LWIP-FATFS-USB/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/STM32/RT-STM32F429-DISCOVERY/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU2;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU2);
+    sduSuspendHookI(&SDU2);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU2);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

demos/STM32/RT-STM32L053-DISCOVERY/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

os/hal/include/hal_buffers.h

@@ -61,6 +61,10 @@ struct io_buffers_queue {
    * @brief   Queue of waiting threads.
    */
   threads_queue_t       waiting;
+  /**
+   * @brief   Queue suspended state flag.
+   */
+  bool                  suspended;
   /**
    * @brief   Active buffers counter.
    */
@@ -170,6 +174,48 @@ typedef io_buffers_queue_t output_buffers_queue_t;
  */
 #define bqGetLinkX(bqp) ((bqp)->link)
 
+/**
+ * @brief   Return the suspended state of the queue.
+ *
+ * @param[in] bqp       pointer to an @p io_buffers_queue_t structure
+ * @return              The suspended state.
+ * @retval false        if blocking access to the queue is enabled.
+ * @retval true         if blocking access to the queue is suspended.
+ *
+ * @xclass
+ */
+#define bqIsSuspendedX(bqp) ((bqp)->suspended)
+
+/**
+ * @brief   Puts the queue in suspended state.
+ * @details When the queue is put in suspended state all waiting threads are
+ *          woken with message @p MSG_RESET and subsequent attempt at waiting
+ *          on the queue will result in an immediate return with @p MSG_RESET
+ *          message.
+ * @note    The content of the queue is not altered, queues can be accessed
+ *          is suspended state until a blocking operation is met then a
+ *          @p MSG_RESET occurs.
+ *
+ * @param[in] bqp       pointer to an @p io_buffers_queue_t structure
+ *
+ * @iclass
+ */
+#define bqSuspendI(bqp) {                                                   \
+  (bqp)->suspended = true;                                                  \
+  osalThreadDequeueAllI(&(bqp)->waiting, MSG_RESET);                        \
+}
+
+/**
+ * @brief   Resumes normal queue operations.
+ *
+ * @param[in] bqp       pointer to an @p io_buffers_queue_t structure
+ *
+ * @xclass
+ */
+#define bqResumeX(bqp) {                                                    \
+  (bqp)->suspended = false;                                                 \
+}
+
 /**
  * @brief   Evaluates to @p TRUE if the specified input buffers queue is empty.
  *
@@ -232,9 +278,8 @@ typedef io_buffers_queue_t output_buffers_queue_t;
 #ifdef __cplusplus
 extern "C" {
 #endif
-  void ibqObjectInit(input_buffers_queue_t *ibqp, uint8_t *bp,
+  void ibqObjectInit(input_buffers_queue_t *ibqp, bool suspended, uint8_t *bp,
-                     size_t size, size_t n,
+                     size_t size, size_t n, bqnotify_t infy, void *link);
-                     bqnotify_t infy, void *link);
   void ibqResetI(input_buffers_queue_t *ibqp);
   uint8_t *ibqGetEmptyBufferI(input_buffers_queue_t *ibqp);
   void ibqPostFullBufferI(input_buffers_queue_t *ibqp, size_t size);
@@ -247,9 +292,8 @@ extern "C" {
   msg_t ibqGetTimeout(input_buffers_queue_t *ibqp, systime_t timeout);
   size_t ibqReadTimeout(input_buffers_queue_t *ibqp, uint8_t *bp,
                         size_t n, systime_t timeout);
-  void obqObjectInit(output_buffers_queue_t *obqp, uint8_t *bp,
+  void obqObjectInit(output_buffers_queue_t *obqp, bool suspended, uint8_t *bp,
-                     size_t size, size_t n,
+                     size_t size, size_t n, bqnotify_t onfy, void *link);
-                     bqnotify_t onfy, void *link);
   void obqResetI(output_buffers_queue_t *obqp);
   uint8_t *obqGetFullBufferI(output_buffers_queue_t *obqp,
                              size_t *sizep);

os/hal/include/hal_serial_usb.h

@@ -177,7 +177,8 @@ extern "C" {
   void sduObjectInit(SerialUSBDriver *sdup);
   void sduStart(SerialUSBDriver *sdup, const SerialUSBConfig *config);
   void sduStop(SerialUSBDriver *sdup);
-  void sduDisconnectI(SerialUSBDriver *sdup);
+  void sduSuspendHookI(SerialUSBDriver *sdup);
+  void sduWakeupHookI(SerialUSBDriver *sdup);
   void sduConfigureHookI(SerialUSBDriver *sdup);
   bool sduRequestsHook(USBDriver *usbp);
   void sduSOFHookI(SerialUSBDriver *sdup);

os/hal/src/hal_buffers.c

@@ -64,6 +64,7 @@
  * @brief   Initializes an input buffers queue object.
  *
  * @param[out] ibqp     pointer to the @p input_buffers_queue_t object
+ * @param[in] suspended initial state of the queue
  * @param[in] bp        pointer to a memory area allocated for buffers
  * @param[in] size      buffers size
  * @param[in] n         number of buffers
@@ -72,13 +73,13 @@
  *
  * @init
  */
-void ibqObjectInit(input_buffers_queue_t *ibqp, uint8_t *bp,
+void ibqObjectInit(input_buffers_queue_t *ibqp, bool suspended, uint8_t *bp,
-                   size_t size, size_t n,
+                   size_t size, size_t n, bqnotify_t infy, void *link) {
-                   bqnotify_t infy, void *link) {
 
   osalDbgCheck((ibqp != NULL) && (bp != NULL) && (size >= 2U));
 
   osalThreadQueueObjectInit(&ibqp->waiting);
+  ibqp->suspended = suspended;
   ibqp->bcounter  = 0;
   ibqp->brdptr    = bp;
   ibqp->bwrptr    = bp;
@@ -181,7 +182,8 @@ void ibqPostFullBufferI(input_buffers_queue_t *ibqp, size_t size) {
  * @return              The operation status.
  * @retval MSG_OK       if a buffer has been acquired.
  * @retval MSG_TIMEOUT  if the specified time expired.
- * @retval MSG_RESET    if the queue has been reset.
+ * @retval MSG_RESET    if the queue has been reset or has been put in
+ *                      suspended state.
  *
  * @api
  */
@@ -212,7 +214,8 @@ msg_t ibqGetFullBufferTimeout(input_buffers_queue_t *ibqp,
    * @return              The operation status.
    * @retval MSG_OK       if a buffer has been acquired.
    * @retval MSG_TIMEOUT  if the specified time expired.
-   * @retval MSG_RESET    if the queue has been reset.
+   * @retval MSG_RESET    if the queue has been reset or has been put in
+   *                      suspended state.
    *
    * @sclass
    */
@@ -222,6 +225,9 @@ msg_t ibqGetFullBufferTimeout(input_buffers_queue_t *ibqp,
   osalDbgCheckClassS();
 
   while (ibqIsEmptyI(ibqp)) {
+    if (ibqp->suspended) {
+      return MSG_RESET;
+    }
     msg_t msg = osalThreadEnqueueTimeoutS(&ibqp->waiting, timeout);
     if (msg < MSG_OK) {
        return msg;
@@ -295,7 +301,8 @@ void ibqReleaseEmptyBuffer(input_buffers_queue_t *ibqp) {
  *                      .
  * @return              A byte value from the queue.
  * @retval MSG_TIMEOUT  if the specified time expired.
- * @retval MSG_RESET    if the queue has been reset.
+ * @retval MSG_RESET    if the queue has been reset or has been put in
+ *                      suspended state.
  *
  * @api
  */
@@ -432,6 +439,7 @@ size_t ibqReadTimeout(input_buffers_queue_t *ibqp, uint8_t *bp,
  * @brief   Initializes an output buffers queue object.
  *
  * @param[out] obqp     pointer to the @p output_buffers_queue_t object
+ * @param[in] suspended initial state of the queue
  * @param[in] bp        pointer to a memory area allocated for buffers
  * @param[in] size      buffers size
  * @param[in] n         number of buffers
@@ -440,13 +448,13 @@ size_t ibqReadTimeout(input_buffers_queue_t *ibqp, uint8_t *bp,
  *
  * @init
  */
-void obqObjectInit(output_buffers_queue_t *obqp, uint8_t *bp,
+void obqObjectInit(output_buffers_queue_t *obqp, bool suspended, uint8_t *bp,
-                   size_t size, size_t n,
+                   size_t size, size_t n, bqnotify_t onfy, void *link) {
-                   bqnotify_t onfy, void *link) {
 
   osalDbgCheck((obqp != NULL) && (bp != NULL) && (size >= 2U));
 
   osalThreadQueueObjectInit(&obqp->waiting);
+  obqp->suspended = suspended;
   obqp->bcounter  = n;
   obqp->brdptr    = bp;
   obqp->bwrptr    = bp;
@@ -548,7 +556,8 @@ void obqReleaseEmptyBufferI(output_buffers_queue_t *obqp) {
  * @return              The operation status.
  * @retval MSG_OK       if a buffer has been acquired.
  * @retval MSG_TIMEOUT  if the specified time expired.
- * @retval MSG_RESET    if the queue has been reset.
+ * @retval MSG_RESET    if the queue has been reset or has been put in
+ *                      suspended state.
  *
  * @api
  */
@@ -579,7 +588,8 @@ msg_t obqGetEmptyBufferTimeout(output_buffers_queue_t *obqp,
  * @return              The operation status.
  * @retval MSG_OK       if a buffer has been acquired.
  * @retval MSG_TIMEOUT  if the specified time expired.
-   * @retval MSG_RESET    if the queue has been reset.
+ * @retval MSG_RESET    if the queue has been reset or has been put in
+ *                      suspended state.
  *
  * @sclass
  */
@@ -589,6 +599,9 @@ msg_t obqGetEmptyBufferTimeout(output_buffers_queue_t *obqp,
   osalDbgCheckClassS();
 
   while (obqIsFullI(obqp)) {
+    if (obqp->suspended) {
+      return MSG_RESET;
+    }
     msg_t msg = osalThreadEnqueueTimeoutS(&obqp->waiting, timeout);
     if (msg < MSG_OK) {
       return msg;
@@ -669,7 +682,8 @@ void obqPostFullBufferS(output_buffers_queue_t *obqp, size_t size) {
  *                      .
  * @return              A byte value from the queue.
  * @retval MSG_TIMEOUT  if the specified time expired.
- * @retval MSG_RESET    if the queue has been reset.
+ * @retval MSG_RESET    if the queue has been reset or has been put in
+ *                      suspended state.
  *
  * @api
  */

os/hal/src/hal_serial_usb.c

@@ -84,75 +84,43 @@ static bool sdu_start_receive(SerialUSBDriver *sdup) {
 
 static size_t write(void *ip, const uint8_t *bp, size_t n) {
 
-  if (usbGetDriverStateI(((SerialUSBDriver *)ip)->config->usbp) != USB_ACTIVE) {
-    return 0;
-  }
-
   return obqWriteTimeout(&((SerialUSBDriver *)ip)->obqueue, bp,
                          n, TIME_INFINITE);
 }
 
 static size_t read(void *ip, uint8_t *bp, size_t n) {
 
-  if (usbGetDriverStateI(((SerialUSBDriver *)ip)->config->usbp) != USB_ACTIVE) {
-    return 0;
-  }
-
   return ibqReadTimeout(&((SerialUSBDriver *)ip)->ibqueue, bp,
                         n, TIME_INFINITE);
 }
 
 static msg_t put(void *ip, uint8_t b) {
 
-  if (usbGetDriverStateI(((SerialUSBDriver *)ip)->config->usbp) != USB_ACTIVE) {
-    return MSG_RESET;
-  }
-
   return obqPutTimeout(&((SerialUSBDriver *)ip)->obqueue, b, TIME_INFINITE);
 }
 
 static msg_t get(void *ip) {
 
-  if (usbGetDriverStateI(((SerialUSBDriver *)ip)->config->usbp) != USB_ACTIVE) {
-    return MSG_RESET;
-  }
-
   return ibqGetTimeout(&((SerialUSBDriver *)ip)->ibqueue, TIME_INFINITE);
 }
 
 static msg_t putt(void *ip, uint8_t b, systime_t timeout) {
 
-  if (usbGetDriverStateI(((SerialUSBDriver *)ip)->config->usbp) != USB_ACTIVE) {
-    return MSG_RESET;
-  }
-
   return obqPutTimeout(&((SerialUSBDriver *)ip)->obqueue, b, timeout);
 }
 
 static msg_t gett(void *ip, systime_t timeout) {
 
-  if (usbGetDriverStateI(((SerialUSBDriver *)ip)->config->usbp) != USB_ACTIVE) {
-    return MSG_RESET;
-  }
-
   return ibqGetTimeout(&((SerialUSBDriver *)ip)->ibqueue, timeout);
 }
 
 static size_t writet(void *ip, const uint8_t *bp, size_t n, systime_t timeout) {
 
-  if (usbGetDriverStateI(((SerialUSBDriver *)ip)->config->usbp) != USB_ACTIVE) {
-    return 0;
-  }
-
   return obqWriteTimeout(&((SerialUSBDriver *)ip)->obqueue, bp, n, timeout);
 }
 
 static size_t readt(void *ip, uint8_t *bp, size_t n, systime_t timeout) {
 
-  if (usbGetDriverStateI(((SerialUSBDriver *)ip)->config->usbp) != USB_ACTIVE) {
-    return 0;
-  }
-
   return ibqReadTimeout(&((SerialUSBDriver *)ip)->ibqueue, bp, n, timeout);
 }
 
@@ -226,10 +194,10 @@ void sduObjectInit(SerialUSBDriver *sdup) {
   sdup->vmt = &vmt;
   osalEventObjectInit(&sdup->event);
   sdup->state = SDU_STOP;
-  ibqObjectInit(&sdup->ibqueue, sdup->ib,
+  ibqObjectInit(&sdup->ibqueue, true, sdup->ib,
                 SERIAL_USB_BUFFERS_SIZE, SERIAL_USB_BUFFERS_NUMBER,
                 ibnotify, sdup);
-  obqObjectInit(&sdup->obqueue, sdup->ob,
+  obqObjectInit(&sdup->obqueue, true, sdup->ob,
                 SERIAL_USB_BUFFERS_SIZE, SERIAL_USB_BUFFERS_NUMBER,
                 obnotify, sdup);
 }
@@ -289,14 +257,19 @@ void sduStop(SerialUSBDriver *sdup) {
   sdup->state  = SDU_STOP;
 
   /* Enforces a disconnection.*/
-  sduDisconnectI(sdup);
+  chnAddFlagsI(sdup, CHN_DISCONNECTED);
+  ibqResetI(&sdup->ibqueue);
+  obqResetI(&sdup->obqueue);
   osalOsRescheduleS();
 
   osalSysUnlock();
 }
 
 /**
- * @brief   USB device disconnection handler.
+ * @brief   USB device suspend handler.
+ * @details Generates a @p CHN_DISCONNECT event and puts queues in
+ *          non-blocking mode, this way the application cannot get stuck
+ *          in the middle of an I/O operations.
  * @note    If this function is not called from an ISR then an explicit call
  *          to @p osalOsRescheduleS() in necessary afterward.
  *
@@ -304,12 +277,30 @@ void sduStop(SerialUSBDriver *sdup) {
  *
  * @iclass
  */
-void sduDisconnectI(SerialUSBDriver *sdup) {
+void sduSuspendHookI(SerialUSBDriver *sdup) {
 
-  /* Queues reset in order to signal the driver stop to the application.*/
   chnAddFlagsI(sdup, CHN_DISCONNECTED);
-  ibqResetI(&sdup->ibqueue);
+  bqSuspendI(&sdup->ibqueue);
-  obqResetI(&sdup->obqueue);
+  bqSuspendI(&sdup->obqueue);
+}
+
+/**
+ * @brief   USB device wakeup handler.
+ * @details Generates a @p CHN_CONNECT event and resumes normal queues
+ *          operations.
+ *
+ * @note    If this function is not called from an ISR then an explicit call
+ *          to @p osalOsRescheduleS() in necessary afterward.
+ *
+ * @param[in] sdup      pointer to a @p SerialUSBDriver object
+ *
+ * @iclass
+ */
+void sduWakeupHookI(SerialUSBDriver *sdup) {
+
+  chnAddFlagsI(sdup, CHN_CONNECTED);
+  bqResumeX(&sdup->ibqueue);
+  bqResumeX(&sdup->obqueue);
 }
 
 /**
@@ -322,7 +313,9 @@ void sduDisconnectI(SerialUSBDriver *sdup) {
 void sduConfigureHookI(SerialUSBDriver *sdup) {
 
   ibqResetI(&sdup->ibqueue);
+  bqResumeX(&sdup->ibqueue);
   obqResetI(&sdup->obqueue);
+  bqResumeX(&sdup->obqueue);
   chnAddFlagsI(sdup, CHN_CONNECTED);
   (void) sdu_start_receive(sdup);
 }

testex/STM32/STM32F3xx/I2C-LSM303DLHC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testex/STM32/STM32F3xx/SPI-L3GD20/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testex/STM32/STM32F4xx/I2C-LSM303DLHC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testex/STM32/STM32F4xx/SPI-L3GD20/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testex/STM32/STM32F4xx/SPI-LIS302DL/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testex/STM32/STM32F4xx/SPI-LIS3DSH/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F0xx/USB_CDC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F1xx/USB_CDC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F2xx/USB_CDC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F37x/USB_CDC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F3xx/USB_CDC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F3xx/USB_CDC_IAD/usbcfg.c

@@ -373,8 +373,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU2;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -399,18 +397,27 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
-    sduDisconnectI(&SDU2);
+    sduSuspendHookI(&SDU2);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+    sduWakeupHookI(&SDU2);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F4xx/USB_CDC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F4xx/USB_CDC_IAD/usbcfg.c

@@ -373,8 +373,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU2;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -399,18 +397,27 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
-    sduDisconnectI(&SDU2);
+    sduSuspendHookI(&SDU2);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+    sduWakeupHookI(&SDU2);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32F7xx/USB_CDC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU2;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU2);
+    sduSuspendHookI(&SDU2);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU2);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;

testhal/STM32/STM32L4xx/USB_CDC/usbcfg.c

@@ -267,8 +267,6 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
   extern SerialUSBDriver SDU1;
 
   switch (event) {
-  case USB_EVENT_RESET:
-    return;
   case USB_EVENT_ADDRESS:
     return;
   case USB_EVENT_CONFIGURED:
@@ -285,17 +283,25 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
 
     chSysUnlockFromISR();
     return;
+  case USB_EVENT_RESET:
+    /* Falls into.*/
   case USB_EVENT_UNCONFIGURED:
-    return;
+    /* Falls into.*/
   case USB_EVENT_SUSPEND:
     chSysLockFromISR();
 
     /* Disconnection event on suspend.*/
-    sduDisconnectI(&SDU1);
+    sduSuspendHookI(&SDU1);
 
     chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduWakeupHookI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_STALLED:
     return;