i2c: muxes always lock the parent adapter
authorPeter Rosin <peda@axentia.se>
Wed, 4 May 2016 20:15:28 +0000 (22:15 +0200)
committerWolfram Sang <wsa@the-dreams.de>
Wed, 4 May 2016 20:28:31 +0000 (22:28 +0200)
Instead of checking for i2c parent adapters for every lock/unlock, simply
override the locking for muxes to always lock/unlock the parent adapter
directly.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
drivers/i2c/i2c-core.c
drivers/i2c/i2c-mux.c

index 7ef5bd0..afdee66 100644 (file)
@@ -962,12 +962,7 @@ static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
 static void i2c_adapter_lock_bus(struct i2c_adapter *adapter,
                                 unsigned int flags)
 {
-       struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
-
-       if (parent)
-               i2c_lock_adapter(parent);
-       else
-               rt_mutex_lock(&adapter->bus_lock);
+       rt_mutex_lock(&adapter->bus_lock);
 }
 
 /**
@@ -979,12 +974,7 @@ static void i2c_adapter_lock_bus(struct i2c_adapter *adapter,
 static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter,
                                   unsigned int flags)
 {
-       struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
-
-       if (parent)
-               return parent->trylock_bus(parent, flags);
-       else
-               return rt_mutex_trylock(&adapter->bus_lock);
+       return rt_mutex_trylock(&adapter->bus_lock);
 }
 
 /**
@@ -996,12 +986,7 @@ static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter,
 static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter,
                                   unsigned int flags)
 {
-       struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
-
-       if (parent)
-               i2c_unlock_adapter(parent);
-       else
-               rt_mutex_unlock(&adapter->bus_lock);
+       rt_mutex_unlock(&adapter->bus_lock);
 }
 
 static void i2c_dev_set_name(struct i2c_adapter *adap,
index 25e9336..5fa8af7 100644 (file)
@@ -98,6 +98,33 @@ static unsigned int i2c_mux_parent_classes(struct i2c_adapter *parent)
        return class;
 }
 
+static void i2c_parent_lock_bus(struct i2c_adapter *adapter,
+                               unsigned int flags)
+{
+       struct i2c_mux_priv *priv = adapter->algo_data;
+       struct i2c_adapter *parent = priv->muxc->parent;
+
+       parent->lock_bus(parent, flags);
+}
+
+static int i2c_parent_trylock_bus(struct i2c_adapter *adapter,
+                                 unsigned int flags)
+{
+       struct i2c_mux_priv *priv = adapter->algo_data;
+       struct i2c_adapter *parent = priv->muxc->parent;
+
+       return parent->trylock_bus(parent, flags);
+}
+
+static void i2c_parent_unlock_bus(struct i2c_adapter *adapter,
+                                 unsigned int flags)
+{
+       struct i2c_mux_priv *priv = adapter->algo_data;
+       struct i2c_adapter *parent = priv->muxc->parent;
+
+       parent->unlock_bus(parent, flags);
+}
+
 struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent,
                                   struct device *dev, int max_adapters,
                                   int sizeof_priv, u32 flags,
@@ -165,6 +192,9 @@ int i2c_mux_add_adapter(struct i2c_mux_core *muxc,
        priv->adap.retries = parent->retries;
        priv->adap.timeout = parent->timeout;
        priv->adap.quirks = parent->quirks;
+       priv->adap.lock_bus = i2c_parent_lock_bus;
+       priv->adap.trylock_bus = i2c_parent_trylock_bus;
+       priv->adap.unlock_bus = i2c_parent_unlock_bus;
 
        /* Sanity check on class */
        if (i2c_mux_parent_classes(parent) & class)