Improvements to the USB driver, first phase.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@3449 35acf78f-673a-0410-8e92-d51de3d6d3f4

1 files changed, 57 insertions, 34 deletions

diff --git a/os/hal/src/serial_usb.c b/os/hal/src/serial_usb.c
index 16822502a..ea434b197 100644
--- a/os/hal/src/serial_usb.c
+++ b/os/hal/src/serial_usb.c
@@ -118,21 +118,26 @@ static const struct SerialUSBDriverVMT vmt = {
  */

 static void inotify(GenericQueue *qp) {

   SerialUSBDriver *sdup = (SerialUSBDriver *)qp->q_wrptr;

-  size_t n;

 

   /* Writes to the input queue can only happen when the queue has been

      emptied, then a whole packet is loaded in the queue.*/

-  if (chIQIsEmptyI(&sdup->iqueue)) {

-

-    n = usbReadPacketI(sdup->config->usbp, USB_CDC_DATA_AVAILABLE_EP,

-                       sdup->iqueue.q_buffer, SERIAL_USB_BUFFERS_SIZE);

-    if (n != USB_ENDPOINT_BUSY) {

-      chIOAddFlagsI(sdup, IO_INPUT_AVAILABLE);

-      sdup->iqueue.q_rdptr = sdup->iqueue.q_buffer;

-      sdup->iqueue.q_counter = n;

-      while (notempty(&sdup->iqueue.q_waiting))

-        chSchReadyI(fifo_remove(&sdup->iqueue.q_waiting))->p_u.rdymsg = Q_OK;

-    }

+  if (!usbGetReceiveStatusI(sdup->config->usbp, USB_CDC_DATA_AVAILABLE_EP) &&

+      chIQIsEmptyI(&sdup->iqueue)) {

+    chSysUnlock();

+

+    /* Unlocked to make the potentially long read operation preemptable.*/

+    size_t n = usbReadPacketBuffer(sdup->config->usbp,

+                                   USB_CDC_DATA_AVAILABLE_EP,

+                                   sdup->iqueue.q_buffer,

+                                   SERIAL_USB_BUFFERS_SIZE);

+

+    chSysLock();

+    usbStartReceiveI(sdup->config->usbp, USB_CDC_DATA_AVAILABLE_EP);

+    chIOAddFlagsI(sdup, IO_INPUT_AVAILABLE);

+    sdup->iqueue.q_rdptr = sdup->iqueue.q_buffer;

+    sdup->iqueue.q_counter = n;

+    while (notempty(&sdup->iqueue.q_waiting))

+      chSchReadyI(fifo_remove(&sdup->iqueue.q_waiting))->p_u.rdymsg = Q_OK;

   }

 }

 

@@ -141,14 +146,20 @@ static void inotify(GenericQueue *qp) {
  */

 static void onotify(GenericQueue *qp) {

   SerialUSBDriver *sdup = (SerialUSBDriver *)qp->q_rdptr;

-  size_t w, n;

+  size_t n;

 

   /* If there is any data in the output queue then it is sent within a

      single packet and the queue is emptied.*/

   n = chOQGetFullI(&sdup->oqueue);

-  w = usbWritePacketI(sdup->config->usbp, USB_CDC_DATA_REQUEST_EP,

-                      sdup->oqueue.q_buffer, n);

-  if (w != USB_ENDPOINT_BUSY) {

+  if (!usbGetTransmitStatusI(sdup->config->usbp, USB_CDC_DATA_REQUEST_EP)) {

+    chSysUnlock();

+

+    /* Unlocked to make the potentially long write operation preemptable.*/

+    usbWritePacketBuffer(sdup->config->usbp, USB_CDC_DATA_REQUEST_EP,

+                         sdup->oqueue.q_buffer, n);

+

+    chSysLock();

+    usbStartTransmitI(sdup->config->usbp, USB_CDC_DATA_REQUEST_EP);

     chIOAddFlagsI(sdup, IO_OUTPUT_EMPTY);

     sdup->oqueue.q_wrptr = sdup->oqueue.q_buffer;

     sdup->oqueue.q_counter = chQSizeI(&sdup->oqueue);

@@ -285,21 +296,27 @@ bool_t sduRequestsHook(USBDriver *usbp) {
  */

 void sduDataTransmitted(USBDriver *usbp, usbep_t ep) {

   SerialUSBDriver *sdup = usbp->param;

-  size_t n, w;

+  size_t n;

 

   chSysLockFromIsr();

   /* If there is any data in the output queue then it is sent within a

      single packet and the queue is emptied.*/

   n = chOQGetFullI(&sdup->oqueue);

   if (n > 0) {

-    w = usbWritePacketI(usbp, ep, sdup->oqueue.q_buffer, n);

-    if (w != USB_ENDPOINT_BUSY) {

-      chIOAddFlagsI(sdup, IO_OUTPUT_EMPTY);

-      sdup->oqueue.q_wrptr = sdup->oqueue.q_buffer;

-      sdup->oqueue.q_counter = chQSizeI(&sdup->oqueue);

-      while (notempty(&sdup->oqueue.q_waiting))

-        chSchReadyI(fifo_remove(&sdup->oqueue.q_waiting))->p_u.rdymsg = Q_OK;

-    }

+    /* The endpoint cannot be busy, we are in the context of the callback,

+       so it is safe to transmit without a check.*/

+    chSysUnlockFromIsr();

+

+    /* Unlocked to make the potentially long write operation preemptable.*/

+    usbWritePacketBuffer(usbp, ep, sdup->oqueue.q_buffer, n);

+

+    chSysLockFromIsr();

+    usbStartTransmitI(usbp, ep);

+    chIOAddFlagsI(sdup, IO_OUTPUT_EMPTY);

+    sdup->oqueue.q_wrptr = sdup->oqueue.q_buffer;

+    sdup->oqueue.q_counter = chQSizeI(&sdup->oqueue);

+    while (notempty(&sdup->oqueue.q_waiting))

+      chSchReadyI(fifo_remove(&sdup->oqueue.q_waiting))->p_u.rdymsg = Q_OK;

   }

   chSysUnlockFromIsr();

 }

@@ -319,17 +336,23 @@ void sduDataReceived(USBDriver *usbp, usbep_t ep) {
   /* Writes to the input queue can only happen when the queue has been

      emptied, then a whole packet is loaded in the queue.*/

   if (chIQIsEmptyI(&sdup->iqueue)) {

+    /* The endpoint cannot be busy, we are in the context of the callback,

+       so a packet is in the buffer for sure.*/

     size_t n;

 

-    n = usbReadPacketI(usbp, ep, sdup->iqueue.q_buffer,

-                       SERIAL_USB_BUFFERS_SIZE);

-    if (n != USB_ENDPOINT_BUSY) {

-      chIOAddFlagsI(sdup, IO_INPUT_AVAILABLE);

-      sdup->iqueue.q_rdptr = sdup->iqueue.q_buffer;

-      sdup->iqueue.q_counter = n;

-      while (notempty(&sdup->iqueue.q_waiting))

-        chSchReadyI(fifo_remove(&sdup->iqueue.q_waiting))->p_u.rdymsg = Q_OK;

-    }

+    chSysUnlockFromIsr();

+

+    /* Unlocked to make the potentially long write operation preemptable.*/

+    n = usbReadPacketBuffer(usbp, ep, sdup->iqueue.q_buffer,

+                            SERIAL_USB_BUFFERS_SIZE);

+

+    chSysLockFromIsr();

+    usbStartReceiveI(usbp, ep);

+    chIOAddFlagsI(sdup, IO_INPUT_AVAILABLE);

+    sdup->iqueue.q_rdptr = sdup->iqueue.q_buffer;

+    sdup->iqueue.q_counter = n;

+    while (notempty(&sdup->iqueue.q_waiting))

+      chSchReadyI(fifo_remove(&sdup->iqueue.q_waiting))->p_u.rdymsg = Q_OK;

   }

   chSysUnlockFromIsr();

 }