---

yaml
---
r: 273339
b: refs/heads/master
c: 300bab9
h: refs/heads/master
i:
  273337: 38fb17f
  273335: 9446cba
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c536abfdf5227987b8a72ff955b64e62fd58fe91
+refs/heads/master: 300bab9770e2bd10262bcc78e7249fdce2c74b38

trunk/Documentation/hwspinlock.txt

@@ -227,42 +227,62 @@ int hwspinlock_example2(void)
 
 4. API for implementors
 
-  int hwspin_lock_register(struct hwspinlock *hwlock);
+  int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
+		const struct hwspinlock_ops *ops, int base_id, int num_locks);
    - to be called from the underlying platform-specific implementation, in
-     order to register a new hwspinlock instance. Should be called from
-     a process context (this function might sleep).
+     order to register a new hwspinlock device (which is usually a bank of
+     numerous locks). Should be called from a process context (this function
+     might sleep).
      Returns 0 on success, or appropriate error code on failure.
 
-  struct hwspinlock *hwspin_lock_unregister(unsigned int id);
+  int hwspin_lock_unregister(struct hwspinlock_device *bank);
    - to be called from the underlying vendor-specific implementation, in order
-     to unregister an existing (and unused) hwspinlock instance.
+     to unregister an hwspinlock device (which is usually a bank of numerous
+     locks).
      Should be called from a process context (this function might sleep).
      Returns the address of hwspinlock on success, or NULL on error (e.g.
      if the hwspinlock is sill in use).
 
-5. struct hwspinlock
+5. Important structs
 
-This struct represents an hwspinlock instance. It is registered by the
-underlying hwspinlock implementation using the hwspin_lock_register() API.
+struct hwspinlock_device is a device which usually contains a bank
+of hardware locks. It is registered by the underlying hwspinlock
+implementation using the hwspin_lock_register() API.
 
 /**
- * struct hwspinlock - vendor-specific hwspinlock implementation
- *
- * @dev: underlying device, will be used with runtime PM api
- * @ops: vendor-specific hwspinlock handlers
- * @id: a global, unique, system-wide, index of the lock.
- * @lock: initialized and used by hwspinlock core
+ * struct hwspinlock_device - a device which usually spans numerous hwspinlocks
+ * @dev: underlying device, will be used to invoke runtime PM api
+ * @ops: platform-specific hwspinlock handlers
+ * @base_id: id index of the first lock in this device
+ * @num_locks: number of locks in this device
+ * @lock: dynamically allocated array of 'struct hwspinlock'
  */
-struct hwspinlock {
+struct hwspinlock_device {
 	struct device *dev;
 	const struct hwspinlock_ops *ops;
-	int id;
+	int base_id;
+	int num_locks;
+	struct hwspinlock lock[0];
+};
+
+struct hwspinlock_device contains an array of hwspinlock structs, each
+of which represents a single hardware lock:
+
+/**
+ * struct hwspinlock - this struct represents a single hwspinlock instance
+ * @bank: the hwspinlock_device structure which owns this lock
+ * @lock: initialized and used by hwspinlock core
+ * @priv: private data, owned by the underlying platform-specific hwspinlock drv
+ */
+struct hwspinlock {
+	struct hwspinlock_device *bank;
 	spinlock_t lock;
+	void *priv;
 };
 
-The underlying implementation is responsible to assign the dev, ops and id
-members. The lock member, OTOH, is initialized and used by the hwspinlock
-core.
+When registering a bank of locks, the hwspinlock driver only needs to
+set the priv members of the locks. The rest of the members are set and
+initialized by the hwspinlock core itself.
 
 6. Implementation callbacks
 

trunk/drivers/hwspinlock/hwspinlock_core.c

@@ -117,7 +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) {
@@ -199,8 +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;
@@ -245,7 +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)
@@ -257,63 +257,32 @@ 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.
- *
- * 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 *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);
-
 	mutex_lock(&hwspinlock_tree_lock);
 
-	ret = radix_tree_insert(&hwspinlock_tree, hwlock->id, hwlock);
-	if (ret == -EEXIST)
-		pr_err("hwspinlock id %d already exists!\n", hwlock->id);
-	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:
 	mutex_unlock(&hwspinlock_tree_lock);
-	return ret;
+	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.
- *
- * Should be called from a process context (might sleep)
- *
- * 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;
@@ -337,6 +306,88 @@ struct hwspinlock *hwspin_lock_unregister(unsigned int id)
 	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);
 
 /**
@@ -351,24 +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->dev->driver->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 */
@@ -390,7 +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);
 
@@ -465,7 +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);
@@ -500,6 +552,7 @@ EXPORT_SYMBOL_GPL(hwspin_lock_request_specific);
  */
 int hwspin_lock_free(struct hwspinlock *hwlock)
 {
+	struct device *dev = hwlock->bank->dev;
 	struct hwspinlock *tmp;
 	int ret;
 
@@ -511,28 +564,28 @@ int hwspin_lock_free(struct hwspinlock *hwlock)
 	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->dev->driver->owner);
+	module_put(dev->driver->owner);
 
 out:
 	mutex_unlock(&hwspinlock_tree_lock);