text: /****************************************************************************
   * drivers/usbdev/usbdev_trace.c
   *
   *   Copyright (C) 2008-2010, 2012 Gregory Nutt. All rights reserved.
   *   Author: Gregory Nutt <gnutt@nuttx.org>
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   * 3. Neither the name NuttX nor the names of its contributors may be
   *    used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
   * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   ****************************************************************************/
  
  /****************************************************************************
   * Included Files
   ****************************************************************************/
  
  #include <nuttx/config.h>
  
  #include <sys/types.h>
  #include <stdarg.h>
  #include <stdint.h>
  #include <errno.h>
  #include <debug.h>
  
  #include <arch/irq.h>
  #include <nuttx/usb/usbdev_trace.h>
  #undef usbtrace
  
  /****************************************************************************
   * Pre-processor Definitions
   ****************************************************************************/
  
  /* Configuration ************************************************************/
  
  #ifndef CONFIG_USBDEV_TRACE_NRECORDS
  #  define CONFIG_USBDEV_TRACE_NRECORDS 128
  #endif
  
  #ifndef CONFIG_USBDEV_TRACE_INITIALIDSET
  #  define CONFIG_USBDEV_TRACE_INITIALIDSET 0
  #endif
  
  /****************************************************************************
   * Private Types
   ****************************************************************************/
  
  /****************************************************************************
   * Private Function Prototypes
   ****************************************************************************/
  
  /****************************************************************************
   * Private Data
   ****************************************************************************/
  
  #ifdef CONFIG_USBDEV_TRACE
  static struct usbtrace_s g_trace[CONFIG_USBDEV_TRACE_NRECORDS];
  static uint16_t g_head = 0;
  static uint16_t g_tail = 0;
  #endif
  
  #if defined(CONFIG_USBDEV_TRACE) || (defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_USB))
  static usbtrace_idset_t g_maskedidset = CONFIG_USBDEV_TRACE_INITIALIDSET;
  #endif
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: usbtrace_syslog
   ****************************************************************************/
  
  #if !defined(CONFIG_USBDEV_TRACE) && \
      (defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_USB))
  static int usbtrace_syslog(const char *fmt, ...)
  {
    va_list ap;
    int ret;
  
    /* Let lowvsyslog do the real work */
  
    va_start(ap, fmt);
    ret = lowvsyslog(LOG_INFO, fmt, ap);
    va_end(ap);
    return ret;
  }
  #endif
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: usbtrace_enable
   *
   * Description:
   *  Enable/disable tracing per trace ID.  The initial state is all IDs enabled.
   *
   * Input Parameters:
   *  idset - The bitset of IDs to be masked.  TRACE_ALLIDS enables all IDS; zero
   *  masks all IDs.
   *
   * Returned Value:
   *  The previous idset value.
   *
   * Assumptions:
   * - May be called from an interrupt handler
   *
   ****************************************************************************/
  
  #if defined(CONFIG_USBDEV_TRACE) || \
     (defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_USB))
  usbtrace_idset_t usbtrace_enable(usbtrace_idset_t idset)
  {
    irqstate_t flags;
    usbtrace_idset_t ret;
  
    /* The following read and write must be atomic */
  
    flags         = irqsave();
    ret           = g_maskedidset;
    g_maskedidset = idset;
    irqrestore(flags);
    return ret;
  }
  #endif /* CONFIG_USBDEV_TRACE || CONFIG_DEBUG && CONFIG_DEBUG_USB */
  
  /****************************************************************************
   * Name: usbtrace
   *
   * Description:
   *  Record a USB event (tracing must be enabled)
   *
   * Assumptions:
   *   May be called from an interrupt handler
   *
   ****************************************************************************/
  
  #if defined(CONFIG_USBDEV_TRACE) || (defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_USB))
  void usbtrace(uint16_t event, uint16_t value)
  {
    irqstate_t flags;
  
    /* Check if tracing is enabled for this ID */
  
    flags = irqsave();
    if ((g_maskedidset & TRACE_ID2BIT(event)) != 0)
      {
  #ifdef CONFIG_USBDEV_TRACE
        /* Yes... save the new trace data at the head */
  
        g_trace[g_head].event = event;
        g_trace[g_head].value = value;
  
        /* Increment the head and (probably) the tail index */
  
        if (++g_head >= CONFIG_USBDEV_TRACE_NRECORDS)
          {
            g_head = 0;
          }
  
        if (g_head == g_tail)
          {
            if (++g_tail >= CONFIG_USBDEV_TRACE_NRECORDS)
              {
                g_tail = 0;
              }
          }
  #else
        /* Just print the data using lowsyslog */
  
        usbtrace_trprintf(usbtrace_syslog, event, value);
  #endif
      }
  
    irqrestore(flags);
  }
  #endif /* CONFIG_USBDEV_TRACE || CONFIG_DEBUG && CONFIG_DEBUG_USB */
  
  /****************************************************************************
   * Name: usbtrace_enumerate
   *
   * Description:
   *   Enumerate all buffer trace data (will temporarily disable tracing)
   *
   * Assumptions:
   *   NEVER called from an interrupt handler
   *
   ****************************************************************************/
  
  #ifdef CONFIG_USBDEV_TRACE
  int usbtrace_enumerate(trace_callback_t callback, void *arg)
  {
    uint16_t ndx;
    uint32_t idset;
    int ret = OK;
  
    /* Temporarily disable tracing */
  
    idset = usbtrace_enable(0);
  
    /* Visit every entry, starting with the tail */
  
    for (ndx = g_tail; ndx != g_head; )
      {
        /* Call the user provided callback */
  
        ret = callback(&g_trace[ndx], arg);
        if (ret != OK)
          {
            /* Abort the enumeration */
  
            break;
          }
  
        /* Increment the index */
  
        if (++ndx >= CONFIG_USBDEV_TRACE_NRECORDS)
          {
            ndx = 0;
          }
      }
  
    /* Discard the trace data after it has been reported */
  
    g_tail = g_head;
  
    /* Restore tracing state */
  
    (void)usbtrace_enable(idset);
    return ret;
  }
  #endif /* CONFIG_USBDEV_TRACE */
  