2 files changed, 18 insertions, 2 deletions

diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 26fad187d661..b22790268b64 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -52,6 +52,7 @@ struct resource_list {
 
 #define IORESOURCE_MEM_64       0x00100000
 #define IORESOURCE_WINDOW       0x00200000      /* forwarded by bridge */
+#define IORESOURCE_MUXED        0x00400000      /* Resource is software muxed */
 
 #define IORESOURCE_EXCLUSIVE    0x08000000      /* Userland may not map this resource */
 #define IORESOURCE_DISABLED     0x10000000
@@ -143,7 +144,8 @@ static inline unsigned long resource_type(const struct resource *res)
 }
 
 /* Convenience shorthand with allocation */
-#define request_region(start,n,name)    __request_region(&ioport_resource, (start), (n), (name), 0)
+#define request_region(start,n,name)            __request_region(&ioport_resource, (start), (n), (name), 0)
+#define request_muxed_region(start,n,name)      __request_region(&ioport_resource, (start), (n), (name), IORESOURCE_MUXED)
 #define __request_mem_region(start,n,name, excl) __request_region(&iomem_resource, (start), (n), (name), excl)
 #define request_mem_region(start,n,name) __request_region(&iomem_resource, (start), (n), (name), 0)
 #define request_mem_region_exclusive(start,n,name) \
diff --git a/kernel/resource.c b/kernel/resource.c
index 9c358e263534..7b36976e5dea 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -15,6 +15,7 @@
 #include <linux/spinlock.h>
 #include <linux/fs.h>
 #include <linux/proc_fs.h>
+#include <linux/sched.h>
 #include <linux/seq_file.h>
 #include <linux/device.h>
 #include <linux/pfn.h>
@@ -681,6 +682,8 @@ resource_size_t resource_alignment(struct resource *res)
  * release_region releases a matching busy region.
  */
 
+static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
+
 /**
  * __request_region - create a new busy resource region
  * @parent: parent resource descriptor
@@ -693,6 +696,7 @@ struct resource * __request_region(struct resource *parent,
                                    resource_size_t start, resource_size_t n,
                                    const char *name, int flags)
 {
+        DECLARE_WAITQUEUE(wait, current);
         struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
 
         if (!res)
@@ -717,7 +721,15 @@ struct resource * __request_region(struct resource *parent,
                         if (!(conflict->flags & IORESOURCE_BUSY))
                                 continue;
                 }
-
+                if (conflict->flags & flags & IORESOURCE_MUXED) {
+                        add_wait_queue(&muxed_resource_wait, &wait);
+                        write_unlock(&resource_lock);
+                        set_current_state(TASK_UNINTERRUPTIBLE);
+                        schedule();
+                        remove_wait_queue(&muxed_resource_wait, &wait);
+                        write_lock(&resource_lock);
+                        continue;
+                }
                 /* Uhhuh, that didn't work out.. */
                 kfree(res);
                 res = NULL;
@@ -791,6 +803,8 @@ void __release_region(struct resource *parent, resource_size_t start,
                                 break;
                         *p = res->sibling;
                         write_unlock(&resource_lock);
+                        if (res->flags & IORESOURCE_MUXED)
+                                wake_up(&muxed_resource_wait);
                         kfree(res);
                         return;
                 }