More kernel build fixes

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5716 42af7a65-404d-4744-a932-0658087f49c3

include/nuttx/sdio.h

@@ -45,6 +45,7 @@
 #include <sys/types.h>
 #include <stdint.h>
 #include <stdbool.h>
+
 #include <nuttx/wqueue.h>
 
 /****************************************************************************
@@ -658,7 +659,9 @@
  *   thread.
  *
  *   When this method is called, all callbacks should be disabled until they
- *   are enabled via a call to SDIO_CALLBACKENABLE
+ *   are enabled via a call to SDIO_CALLBACKENABLE.
+ *
+ *   NOTE: High-priority work queue support is required.
  *
  * Input Parameters:
  *   dev -      Device-specific state data
@@ -670,7 +673,9 @@
  *
  ****************************************************************************/
 
-#define SDIO_REGISTERCALLBACK(d,c,a) ((d)->registercallback(d,c,a))
+#if defined(CONFIG_SCHED_WORKQUEUE) && defined(CONFIG_SCHED_HPWORK)
+#  define SDIO_REGISTERCALLBACK(d,c,a) ((d)->registercallback(d,c,a))
+#endif
 
 /****************************************************************************
  * Name: SDIO_DMASUPPORTED
@@ -819,8 +824,11 @@ struct sdio_dev_s
   sdio_eventset_t (*eventwait)(FAR struct sdio_dev_s *dev, uint32_t timeout);
   void  (*callbackenable)(FAR struct sdio_dev_s *dev,
           sdio_eventset_t eventset);
+
+#if defined(CONFIG_SCHED_WORKQUEUE) && defined(CONFIG_SCHED_HPWORK)
   int   (*registercallback)(FAR struct sdio_dev_s *dev,
           worker_t callback, void *arg);
+#endif
 
   /* DMA.  CONFIG_SDIO_DMA should be set if the driver supports BOTH DMA
    * and non-DMA transfer modes.  If the driver supports only one mode

include/nuttx/wqueue.h

@@ -116,6 +116,10 @@
   /* To preserve legacy behavior, CONFIG_SCHED_HPWORK is assumed to be true
    * in a flat build (CONFIG_SCHED_KERNEL=n) but must be defined in kernel
    * mode in order to build the high priority work queue.
+   *
+   * In the kernel build, it is possible that no kernel work queues will be
+   * built.  But in the flat build, the high priority work queue will always
+   * be built.
    */
 
 #  undef CONFIG_SCHED_HPWORK