Slightly improved delay logic for the USB host

git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@5064 7fd9a85b-ad96-42d3-883c-3090e2eb8679

nuttx/arch/arm/src/stm32/stm32_otgfshost.c

@@ -1474,7 +1474,7 @@ static int stm32_out_transfer(FAR struct stm32_usbhost_s *priv, int chidx,
                               FAR uint8_t *buffer, size_t buflen)
 {
   FAR struct stm32_chan_s *chan;
-  int ret;
+  int ret = OK;
 
   /* Loop until the transfer completes (i.e., buflen is decremented to zero)
    * or a fatal error occurs (any error other than a simple NAK)
@@ -1484,6 +1484,17 @@ static int stm32_out_transfer(FAR struct stm32_usbhost_s *priv, int chidx,
   chan->buffer = buffer;
   chan->buflen = buflen;
 
+  /* There is a bug in the code at present.  With debug OFF, this driver
+   * overruns the typical FLASH device and there are many problems with
+   * NAKS. Sticking a big delay here allows the device (FLASH drive) to
+   * catch up but sacrifices driver performance.
+   */
+
+#if !defined(CONFIG_DEBUG_VERBOSE) || !defined(CONFIG_DEBUG_USB)
+#warning "REVISIT this delay"
+  usleep(50*1000);
+#endif
+
   while (chan->buflen > 0)
     {
       /* Set up for the wait BEFORE starting the transfer */
@@ -1537,17 +1548,6 @@ static int stm32_out_transfer(FAR struct stm32_usbhost_s *priv, int chidx,
           }
         }
 
-      /* There is a bug in the code at present.  With debug OFF, this driver
-       * overruns the typical FLASH device and there are many problems with
-       * NAKS sticking a big delay here allows the driver to work but with
-       * very poor performance when debug is off.
-       */
-
-#if !defined(CONFIG_DEBUG_VERBOSE) && !defined(CONFIG_DEBUG_USB)
-#warning "REVISIT this delay"
-      usleep(100*1000);
-#endif
-
       /* Start the transfer */
 
       stm32_transfer_start(priv, chidx);
@@ -1557,18 +1557,30 @@ static int stm32_out_transfer(FAR struct stm32_usbhost_s *priv, int chidx,
       ret = stm32_chan_wait(priv, chan);
 
       /* EAGAIN indicates that the device NAKed the transfer and we need
-       * do try again.  Anything else (success or other errors) will
-       * cause use to return
+       * do try again.  NAK retries are not yet supported for OUT transfers
+       * so any unsuccessful response will cause us to abort the OUT
+       * transfer.
        */
 
       if (ret != OK)
         {
           udbg("Transfer failed: %d\n", ret);
-          return ret;
+          break;
         }
     }
 
-  return OK;
+  /* There is a bug in the code at present.  With debug OFF, this driver
+   * overruns the typical FLASH device and there are many problems with
+   * NAKS. Sticking a big delay here allows the device (FLASH drive) to
+   * catch up but sacrifices driver performance.
+   */
+
+#if !defined(CONFIG_DEBUG_VERBOSE) || !defined(CONFIG_DEBUG_USB)
+#warning "REVISIT this delay"
+  usleep(50*1000);
+#endif
+
+  return ret;
 }
 
 /*******************************************************************************
@@ -3086,9 +3098,9 @@ static int stm32_enumerate(FAR struct usbhost_driver_s *drvr)
   priv->chan[chidx].indata1   = false;
   priv->chan[chidx].outdata1  = false;
 
-  /* USB 2.0 spec says at least 50ms delay before port reset */
+  /* USB 2.0 spec says at least 50ms delay before port reset.  We wait 100ms. */
 
-  up_mdelay(100);
+  usleep(100*1000);
 
   /* Reset the host port */
 

nuttx/drivers/usbhost/usbhost_enumerate.c

@@ -42,6 +42,7 @@
 #include <sys/types.h>
 #include <stdint.h>
 #include <string.h>
+#include <unistd.h>
 #include <errno.h>
 #include <assert.h>
 #include <debug.h>
@@ -317,7 +318,7 @@ int usbhost_enumerate(FAR struct usbhost_driver_s *drvr, uint8_t funcaddr,
 
   DEBUGASSERT(drvr && class);
 
-  /* Allocate TD buffers for use in this function.  We will need two:
+  /* Allocate descriptor buffers for use in this function.  We will need two:
    * One for the request and one for the data buffer.
    */
 
@@ -400,7 +401,7 @@ int usbhost_enumerate(FAR struct usbhost_driver_s *drvr, uint8_t funcaddr,
       udbg("ERROR: SETADDRESS DRVR_CTRLOUT returned %d\n", ret);
       goto errout;
     }
-  up_mdelay(2);
+  usleep(2*1000);
 
   /* Modify control pipe with the provided USB device address */
 
@@ -461,9 +462,9 @@ int usbhost_enumerate(FAR struct usbhost_driver_s *drvr, uint8_t funcaddr,
       goto errout;
     }
 
-  /* Free the TD that we were using for the request buffer.  It is not needed
-   * further here but it may be needed by the class driver during its connection
-   * operations.
+  /* Free the descriptor buffer that we were using for the request buffer.
+   * It is not needed further here but it may be needed by the class driver
+   * during its connection operations.
    */
  
   DRVR_FREE(drvr, (uint8_t*)ctrlreq);
@@ -488,9 +489,9 @@ int usbhost_enumerate(FAR struct usbhost_driver_s *drvr, uint8_t funcaddr,
         }
     }
 
-  /* Some devices may require this delay before initialization */
+  /* Some devices may require some delay before initialization */
 
-  up_mdelay(100);
+  usleep(100*1000);
 
   /* Parse the configuration descriptor and bind to the class instance for the
    * device.  This needs to be the last thing done because the class driver

nuttx/drivers/usbhost/usbhost_storage.c

@@ -42,6 +42,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include <semaphore.h>
 #include <assert.h>
 #include <errno.h>
@@ -724,6 +725,7 @@ static inline int usbhost_testunitready(FAR struct usbhost_state_s *priv)
           usbhost_dumpcsw((FAR struct usbmsc_csw_s *)priv->tbuffer);
         }
     }
+
   return result;
 }
 
@@ -1195,13 +1197,15 @@ static inline int usbhost_initvolume(FAR struct usbhost_state_s *priv)
   uvdbg("Get max LUN\n");
   ret = usbhost_maxlunreq(priv);
 
-  /* Wait for the unit to be ready */
-
-  for (retries = 0; retries < USBHOST_MAX_RETRIES && ret == OK; retries++)
+  for (retries = 0; retries < USBHOST_MAX_RETRIES /* && ret == OK */; retries++)
     {
       uvdbg("Test unit ready, retries=%d\n", retries);
 
-      /* Send TESTUNITREADY to see the unit is ready */
+      /* Wait just a bit */
+
+      usleep(50*1000);
+
+      /* Send TESTUNITREADY to see if the unit is ready */
 
       ret = usbhost_testunitready(priv);
       if (ret == OK)