From: Peter Rosin <peda@axentia.se>
Date: Wed, 4 May 2016 20:15:28 +0000 (+0200)
Subject: i2c: muxes always lock the parent adapter
X-Git-Tag: v4.14-rc1~3204^2~12
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fa96f0cb9b37a1a296d18f7bde63b0910852303e;p=platform%2Fkernel%2Flinux-rpi.git

i2c: muxes always lock the parent adapter

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>
---

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 7ef5bd0..afdee66 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -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,
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 25e9336..5fa8af7 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -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)