Merge ../linus

[pandora-kernel.git] / arch / powerpc / platforms / powermac / pfunc_core.c

diff --git a/arch/powerpc/platforms/powermac/pfunc_core.c b/arch/powerpc/platforms/powermac/pfunc_core.c
index 4baa75b..93e7505 100644 (file)
--- a/arch/powerpc/platforms/powermac/pfunc_core.c
+++ b/arch/powerpc/platforms/powermac/pfunc_core.c
@@ -11,6 +11,7 @@
 #include <linux/kernel.h>
 #include <linux/spinlock.h>
 #include <linux/module.h>
+#include <linux/mutex.h>
 
 #include <asm/semaphore.h>
 #include <asm/prom.h>
@@ -545,7 +546,8 @@ struct pmf_device {
 };
 
 static LIST_HEAD(pmf_devices);
-static spinlock_t pmf_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(pmf_lock);
+static DEFINE_MUTEX(pmf_irq_mutex);
 
 static void pmf_release_device(struct kref *kref)
 {
@@ -864,16 +866,25 @@ int pmf_register_irq_client(struct device_node *target,
 
        spin_lock_irqsave(&pmf_lock, flags);
        func = __pmf_find_function(target, name, PMF_FLAGS_INT_GEN);
-       if (func == NULL) {
-               spin_unlock_irqrestore(&pmf_lock, flags);
+       if (func)
+               func = pmf_get_function(func);
+       spin_unlock_irqrestore(&pmf_lock, flags);
+       if (func == NULL)
                return -ENODEV;
-       }
+
+       /* guard against manipulations of list */
+       mutex_lock(&pmf_irq_mutex);
        if (list_empty(&func->irq_clients))
                func->dev->handlers->irq_enable(func);
+
+       /* guard against pmf_do_irq while changing list */
+       spin_lock_irqsave(&pmf_lock, flags);
        list_add(&client->link, &func->irq_clients);
-       client->func = func;
        spin_unlock_irqrestore(&pmf_lock, flags);
 
+       client->func = func;
+       mutex_unlock(&pmf_irq_mutex);
+
        return 0;
 }
 EXPORT_SYMBOL_GPL(pmf_register_irq_client);
@@ -885,12 +896,19 @@ void pmf_unregister_irq_client(struct pmf_irq_client *client)
 
        BUG_ON(func == NULL);
 
-       spin_lock_irqsave(&pmf_lock, flags);
+       /* guard against manipulations of list */
+       mutex_lock(&pmf_irq_mutex);
        client->func = NULL;
+
+       /* guard against pmf_do_irq while changing list */
+       spin_lock_irqsave(&pmf_lock, flags);
        list_del(&client->link);
+       spin_unlock_irqrestore(&pmf_lock, flags);
+
        if (list_empty(&func->irq_clients))
                func->dev->handlers->irq_disable(func);
-       spin_unlock_irqrestore(&pmf_lock, flags);
+       mutex_unlock(&pmf_irq_mutex);
+       pmf_put_function(func);
 }
 EXPORT_SYMBOL_GPL(pmf_unregister_irq_client);