A little more USB host logic

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3178 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 28 insertions, 2 deletions

diff --git a/nuttx/drivers/usbhost/usbhost_registerclass.c b/nuttx/drivers/usbhost/usbhost_registerclass.c
index e81fef9fe..d924de932 100644
--- a/nuttx/drivers/usbhost/usbhost_registerclass.c
+++ b/nuttx/drivers/usbhost/usbhost_registerclass.c
@@ -42,6 +42,17 @@
 #include <errno.h>
 
 #include <nuttx/usb/usbhost.h>
+#include <arch/irq.h>
+
+#include "usbhost_registry.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
 
 /****************************************************************************
  * Private Function Prototypes
@@ -81,7 +92,22 @@
 
 int usbhost_registerclass(struct usbhost_registry_s *class)
 {
-#warning "Not Implemented"
-  return -ENOSYS;
+  irqstate_t flags;
+
+  /* g_classregistry is a singly-linkedlist of class ID information added by
+   * calls to usbhost_registerclass().  Since this list is accessed from USB
+   * host controller interrupt handling logic, accesses to this list must be
+   * protected by disabling interrupts.
+   */
+
+  flags = irqsave();
+
+  /* Add the new class ID info to the head of the list */
+
+  class->flink    = g_classregistry;
+  g_classregistry = class;
+
+  irqrestore(flags);
+  return OK;
 }