1 files changed, 127 insertions, 77 deletions

diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c
index 43a62714b4fb..61c9cf15fa52 100644
--- a/drivers/hwspinlock/hwspinlock_core.c
+++ b/drivers/hwspinlock/hwspinlock_core.c
@@ -26,6 +26,7 @@
 #include <linux/radix-tree.h>
 #include <linux/hwspinlock.h>
 #include <linux/pm_runtime.h>
+#include <linux/mutex.h>
 
 #include "hwspinlock_internal.h"
 
@@ -52,10 +53,12 @@
 static RADIX_TREE(hwspinlock_tree, GFP_KERNEL);
 
 /*
- * Synchronization of access to the tree is achieved using this spinlock,
+ * Synchronization of access to the tree is achieved using this mutex,
  * as the radix-tree API requires that users provide all synchronisation.
+ * A mutex is needed because we're using non-atomic radix tree allocations.
  */
-static DEFINE_SPINLOCK(hwspinlock_tree_lock);
+static DEFINE_MUTEX(hwspinlock_tree_lock);
+
 
 /**
  * __hwspin_trylock() - attempt to lock a specific hwspinlock
@@ -114,7 +117,7 @@ int __hwspin_trylock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
                 return -EBUSY;
 
         /* try to take the hwspinlock device */
-        ret = hwlock->ops->trylock(hwlock);
+        ret = hwlock->bank->ops->trylock(hwlock);
 
         /* if hwlock is already taken, undo spin_trylock_* and exit */
         if (!ret) {
@@ -196,8 +199,8 @@ int __hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int to,
                  * Allow platform-specific relax handlers to prevent
                  * hogging the interconnect (no sleeping, though)
                  */
-                if (hwlock->ops->relax)
-                        hwlock->ops->relax(hwlock);
+                if (hwlock->bank->ops->relax)
+                        hwlock->bank->ops->relax(hwlock);
         }
 
         return ret;
@@ -242,7 +245,7 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
          */
         mb();
 
-        hwlock->ops->unlock(hwlock);
+        hwlock->bank->ops->unlock(hwlock);
 
         /* Undo the spin_trylock{_irq, _irqsave} called while locking */
         if (mode == HWLOCK_IRQSTATE)
@@ -254,68 +257,37 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags)
 }
 EXPORT_SYMBOL_GPL(__hwspin_unlock);
 
-/**
- * hwspin_lock_register() - register a new hw spinlock
- * @hwlock: hwspinlock to register.
- *
- * This function should be called from the underlying platform-specific
- * implementation, to register a new hwspinlock instance.
- *
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context.
- *
- * Returns 0 on success, or an appropriate error code on failure
- */
-int hwspin_lock_register(struct hwspinlock *hwlock)
+static int hwspin_lock_register_single(struct hwspinlock *hwlock, int id)
 {
         struct hwspinlock *tmp;
         int ret;
 
-        if (!hwlock || !hwlock->ops ||
-                !hwlock->ops->trylock || !hwlock->ops->unlock) {
-                pr_err("invalid parameters\n");
-                return -EINVAL;
-        }
-
-        spin_lock_init(&hwlock->lock);
-
-        spin_lock(&hwspinlock_tree_lock);
+        mutex_lock(&hwspinlock_tree_lock);
 
-        ret = radix_tree_insert(&hwspinlock_tree, hwlock->id, hwlock);
-        if (ret)
+        ret = radix_tree_insert(&hwspinlock_tree, id, hwlock);
+        if (ret) {
+                if (ret == -EEXIST)
+                        pr_err("hwspinlock id %d already exists!\n", id);
                 goto out;
+        }
 
         /* mark this hwspinlock as available */
-        tmp = radix_tree_tag_set(&hwspinlock_tree, hwlock->id,
-                                                        HWSPINLOCK_UNUSED);
+        tmp = radix_tree_tag_set(&hwspinlock_tree, id, HWSPINLOCK_UNUSED);
 
         /* self-sanity check which should never fail */
         WARN_ON(tmp != hwlock);
 
 out:
-        spin_unlock(&hwspinlock_tree_lock);
-        return ret;
+        mutex_unlock(&hwspinlock_tree_lock);
+        return 0;
 }
-EXPORT_SYMBOL_GPL(hwspin_lock_register);
 
-/**
- * hwspin_lock_unregister() - unregister an hw spinlock
- * @id: index of the specific hwspinlock to unregister
- *
- * This function should be called from the underlying platform-specific
- * implementation, to unregister an existing (and unused) hwspinlock.
- *
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context.
- *
- * Returns the address of hwspinlock @id on success, or NULL on failure
- */
-struct hwspinlock *hwspin_lock_unregister(unsigned int id)
+static struct hwspinlock *hwspin_lock_unregister_single(unsigned int id)
 {
         struct hwspinlock *hwlock = NULL;
         int ret;
 
-        spin_lock(&hwspinlock_tree_lock);
+        mutex_lock(&hwspinlock_tree_lock);
 
         /* make sure the hwspinlock is not in use (tag is set) */
         ret = radix_tree_tag_get(&hwspinlock_tree, id, HWSPINLOCK_UNUSED);
@@ -331,9 +303,91 @@ struct hwspinlock *hwspin_lock_unregister(unsigned int id)
         }
 
 out:
-        spin_unlock(&hwspinlock_tree_lock);
+        mutex_unlock(&hwspinlock_tree_lock);
         return hwlock;
 }
+
+/**
+ * hwspin_lock_register() - register a new hw spinlock device
+ * @bank: the hwspinlock device, which usually provides numerous hw locks
+ * @dev: the backing device
+ * @ops: hwspinlock handlers for this device
+ * @base_id: id of the first hardware spinlock in this bank
+ * @num_locks: number of hwspinlocks provided by this device
+ *
+ * This function should be called from the underlying platform-specific
+ * implementation, to register a new hwspinlock device instance.
+ *
+ * Should be called from a process context (might sleep)
+ *
+ * Returns 0 on success, or an appropriate error code on failure
+ */
+int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
+                const struct hwspinlock_ops *ops, int base_id, int num_locks)
+{
+        struct hwspinlock *hwlock;
+        int ret = 0, i;
+
+        if (!bank || !ops || !dev || !num_locks || !ops->trylock ||
+                                                        !ops->unlock) {
+                pr_err("invalid parameters\n");
+                return -EINVAL;
+        }
+
+        bank->dev = dev;
+        bank->ops = ops;
+        bank->base_id = base_id;
+        bank->num_locks = num_locks;
+
+        for (i = 0; i < num_locks; i++) {
+                hwlock = &bank->lock[i];
+
+                spin_lock_init(&hwlock->lock);
+                hwlock->bank = bank;
+
+                ret = hwspin_lock_register_single(hwlock, i);
+                if (ret)
+                        goto reg_failed;
+        }
+
+        return 0;
+
+reg_failed:
+        while (--i >= 0)
+                hwspin_lock_unregister_single(i);
+        return ret;
+}
+EXPORT_SYMBOL_GPL(hwspin_lock_register);
+
+/**
+ * hwspin_lock_unregister() - unregister an hw spinlock device
+ * @bank: the hwspinlock device, which usually provides numerous hw locks
+ *
+ * This function should be called from the underlying platform-specific
+ * implementation, to unregister an existing (and unused) hwspinlock.
+ *
+ * Should be called from a process context (might sleep)
+ *
+ * Returns 0 on success, or an appropriate error code on failure
+ */
+int hwspin_lock_unregister(struct hwspinlock_device *bank)
+{
+        struct hwspinlock *hwlock, *tmp;
+        int i;
+
+        for (i = 0; i < bank->num_locks; i++) {
+                hwlock = &bank->lock[i];
+
+                tmp = hwspin_lock_unregister_single(bank->base_id + i);
+                if (!tmp)
+                        return -EBUSY;
+
+                /* self-sanity check that should never fail */
+                WARN_ON(tmp != hwlock);
+        }
+
+        return 0;
+}
 EXPORT_SYMBOL_GPL(hwspin_lock_unregister);
 
 /**
@@ -348,24 +402,25 @@ EXPORT_SYMBOL_GPL(hwspin_lock_unregister);
  */
 static int __hwspin_lock_request(struct hwspinlock *hwlock)
 {
+        struct device *dev = hwlock->bank->dev;
         struct hwspinlock *tmp;
         int ret;
 
         /* prevent underlying implementation from being removed */
-        if (!try_module_get(hwlock->owner)) {
-                dev_err(hwlock->dev, "%s: can't get owner\n", __func__);
+        if (!try_module_get(dev->driver->owner)) {
+                dev_err(dev, "%s: can't get owner\n", __func__);
                 return -EINVAL;
         }
 
         /* notify PM core that power is now needed */
-        ret = pm_runtime_get_sync(hwlock->dev);
+        ret = pm_runtime_get_sync(dev);
         if (ret < 0) {
-                dev_err(hwlock->dev, "%s: can't power on device\n", __func__);
+                dev_err(dev, "%s: can't power on device\n", __func__);
                 return ret;
         }
 
         /* mark hwspinlock as used, should not fail */
-        tmp = radix_tree_tag_clear(&hwspinlock_tree, hwlock->id,
+        tmp = radix_tree_tag_clear(&hwspinlock_tree, hwlock_to_id(hwlock),
                                                         HWSPINLOCK_UNUSED);
 
         /* self-sanity check that should never fail */
@@ -387,7 +442,7 @@ int hwspin_lock_get_id(struct hwspinlock *hwlock)
                 return -EINVAL;
         }
 
-        return hwlock->id;
+        return hwlock_to_id(hwlock);
 }
 EXPORT_SYMBOL_GPL(hwspin_lock_get_id);
 
@@ -400,9 +455,7 @@ EXPORT_SYMBOL_GPL(hwspin_lock_get_id);
  * to the remote core before it can be used for synchronization (to get the
  * id of a given hwlock, use hwspin_lock_get_id()).
  *
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context (simply because there is no use case for
- * that yet).
+ * Should be called from a process context (might sleep)
  *
  * Returns the address of the assigned hwspinlock, or NULL on error
  */
@@ -411,7 +464,7 @@ struct hwspinlock *hwspin_lock_request(void)
         struct hwspinlock *hwlock;
         int ret;
 
-        spin_lock(&hwspinlock_tree_lock);
+        mutex_lock(&hwspinlock_tree_lock);
 
         /* look for an unused lock */
         ret = radix_tree_gang_lookup_tag(&hwspinlock_tree, (void **)&hwlock,
@@ -431,7 +484,7 @@ struct hwspinlock *hwspin_lock_request(void)
                 hwlock = NULL;
 
 out:
-        spin_unlock(&hwspinlock_tree_lock);
+        mutex_unlock(&hwspinlock_tree_lock);
         return hwlock;
 }
 EXPORT_SYMBOL_GPL(hwspin_lock_request);
@@ -445,9 +498,7 @@ EXPORT_SYMBOL_GPL(hwspin_lock_request);
  * Usually early board code will be calling this function in order to
  * reserve specific hwspinlock ids for predefined purposes.
  *
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context (simply because there is no use case for
- * that yet).
+ * Should be called from a process context (might sleep)
  *
  * Returns the address of the assigned hwspinlock, or NULL on error
  */
@@ -456,7 +507,7 @@ struct hwspinlock *hwspin_lock_request_specific(unsigned int id)
         struct hwspinlock *hwlock;
         int ret;
 
-        spin_lock(&hwspinlock_tree_lock);
+        mutex_lock(&hwspinlock_tree_lock);
 
         /* make sure this hwspinlock exists */
         hwlock = radix_tree_lookup(&hwspinlock_tree, id);
@@ -466,7 +517,7 @@ struct hwspinlock *hwspin_lock_request_specific(unsigned int id)
         }
 
         /* sanity check (this shouldn't happen) */
-        WARN_ON(hwlock->id != id);
+        WARN_ON(hwlock_to_id(hwlock) != id);
 
         /* make sure this hwspinlock is unused */
         ret = radix_tree_tag_get(&hwspinlock_tree, id, HWSPINLOCK_UNUSED);
@@ -482,7 +533,7 @@ struct hwspinlock *hwspin_lock_request_specific(unsigned int id)
                 hwlock = NULL;
 
 out:
-        spin_unlock(&hwspinlock_tree_lock);
+        mutex_unlock(&hwspinlock_tree_lock);
         return hwlock;
 }
 EXPORT_SYMBOL_GPL(hwspin_lock_request_specific);
@@ -495,14 +546,13 @@ EXPORT_SYMBOL_GPL(hwspin_lock_request_specific);
  * Should only be called with an @hwlock that was retrieved from
  * an earlier call to omap_hwspin_lock_request{_specific}.
  *
- * Can be called from an atomic context (will not sleep) but not from
- * within interrupt context (simply because there is no use case for
- * that yet).
+ * Should be called from a process context (might sleep)
  *
  * Returns 0 on success, or an appropriate error code on failure
  */
 int hwspin_lock_free(struct hwspinlock *hwlock)
 {
+        struct device *dev = hwlock->bank->dev;
         struct hwspinlock *tmp;
         int ret;
 
@@ -511,34 +561,34 @@ int hwspin_lock_free(struct hwspinlock *hwlock)
                 return -EINVAL;
         }
 
-        spin_lock(&hwspinlock_tree_lock);
+        mutex_lock(&hwspinlock_tree_lock);
 
         /* make sure the hwspinlock is used */
-        ret = radix_tree_tag_get(&hwspinlock_tree, hwlock->id,
+        ret = radix_tree_tag_get(&hwspinlock_tree, hwlock_to_id(hwlock),
                                                         HWSPINLOCK_UNUSED);
         if (ret == 1) {
-                dev_err(hwlock->dev, "%s: hwlock is already free\n", __func__);
+                dev_err(dev, "%s: hwlock is already free\n", __func__);
                 dump_stack();
                 ret = -EINVAL;
                 goto out;
         }
 
         /* notify the underlying device that power is not needed */
-        ret = pm_runtime_put(hwlock->dev);
+        ret = pm_runtime_put(dev);
         if (ret < 0)
                 goto out;
 
         /* mark this hwspinlock as available */
-        tmp = radix_tree_tag_set(&hwspinlock_tree, hwlock->id,
+        tmp = radix_tree_tag_set(&hwspinlock_tree, hwlock_to_id(hwlock),
                                                         HWSPINLOCK_UNUSED);
 
         /* sanity check (this shouldn't happen) */
         WARN_ON(tmp != hwlock);
 
-        module_put(hwlock->owner);
+        module_put(dev->driver->owner);
 
 out:
-        spin_unlock(&hwspinlock_tree_lock);
+        mutex_unlock(&hwspinlock_tree_lock);
         return ret;
 }
 EXPORT_SYMBOL_GPL(hwspin_lock_free);