From 7f101a97866e2687a455ecffeb96bcf317c8482a Mon Sep 17 00:00:00 2001
From: Dave Young <hidave.darkstar@gmail.com>
Date: Mon, 14 Jul 2008 22:38:19 +0200
Subject: [PATCH] i2c: Use class_for_each_device

Use class_for_each_device for iteration.

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
---
 drivers/i2c/i2c-core.c | 92 ++++++++++++++++++++++--------------------
 1 file changed, 48 insertions(+), 44 deletions(-)

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index d0175f4f8fc6..f489683fd15f 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -35,7 +35,6 @@
 #include <linux/completion.h>
 #include <linux/hardirq.h>
 #include <linux/irqflags.h>
-#include <linux/semaphore.h>
 #include <asm/uaccess.h>
 
 #include "i2c-core.h"
@@ -646,6 +645,16 @@ EXPORT_SYMBOL(i2c_del_adapter);
 
 /* ------------------------------------------------------------------------- */
 
+static int __attach_adapter(struct device *dev, void *data)
+{
+	struct i2c_adapter *adapter = to_i2c_adapter(dev);
+	struct i2c_driver *driver = data;
+
+	driver->attach_adapter(adapter);
+
+	return 0;
+}
+
 /*
  * An i2c_driver is used with one or more i2c_client (device) nodes to access
  * i2c slave chips, on a bus instance associated with some i2c_adapter.  There
@@ -686,21 +695,49 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
 	pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name);
 
 	/* legacy drivers scan i2c busses directly */
-	if (driver->attach_adapter) {
-		struct i2c_adapter *adapter;
+	if (driver->attach_adapter)
+		class_for_each_device(&i2c_adapter_class, driver,
+				      __attach_adapter);
 
-		down(&i2c_adapter_class.sem);
-		list_for_each_entry(adapter, &i2c_adapter_class.devices,
-				    dev.node) {
-			driver->attach_adapter(adapter);
+	mutex_unlock(&core_lock);
+	return 0;
+}
+EXPORT_SYMBOL(i2c_register_driver);
+
+static int __detach_adapter(struct device *dev, void *data)
+{
+	struct i2c_adapter *adapter = to_i2c_adapter(dev);
+	struct i2c_driver *driver = data;
+
+	/* Have a look at each adapter, if clients of this driver are still
+	 * attached. If so, detach them to be able to kill the driver
+	 * afterwards.
+	 */
+	if (driver->detach_adapter) {
+		if (driver->detach_adapter(adapter))
+			dev_err(&adapter->dev,
+				"detach_adapter failed for driver [%s]\n",
+				driver->driver.name);
+	} else {
+		struct list_head *item, *_n;
+		struct i2c_client *client;
+
+		list_for_each_safe(item, _n, &adapter->clients) {
+			client = list_entry(item, struct i2c_client, list);
+			if (client->driver != driver)
+				continue;
+			dev_dbg(&adapter->dev,
+				"detaching client [%s] at 0x%02x\n",
+				client->name, client->addr);
+			if (driver->detach_client(client))
+				dev_err(&adapter->dev, "detach_client "
+					"failed for client [%s] at 0x%02x\n",
+					client->name, client->addr);
 		}
-		up(&i2c_adapter_class.sem);
 	}
 
-	mutex_unlock(&core_lock);
 	return 0;
 }
-EXPORT_SYMBOL(i2c_register_driver);
 
 /**
  * i2c_del_driver - unregister I2C driver
@@ -709,46 +746,13 @@ EXPORT_SYMBOL(i2c_register_driver);
  */
 void i2c_del_driver(struct i2c_driver *driver)
 {
-	struct list_head   *item2, *_n;
-	struct i2c_client  *client;
-	struct i2c_adapter *adap;
-
 	mutex_lock(&core_lock);
 
 	/* new-style driver? */
 	if (is_newstyle_driver(driver))
 		goto unregister;
 
-	/* Have a look at each adapter, if clients of this driver are still
-	 * attached. If so, detach them to be able to kill the driver
-	 * afterwards.
-	 */
-	down(&i2c_adapter_class.sem);
-	list_for_each_entry(adap, &i2c_adapter_class.devices, dev.node) {
-		if (driver->detach_adapter) {
-			if (driver->detach_adapter(adap)) {
-				dev_err(&adap->dev, "detach_adapter failed "
-					"for driver [%s]\n",
-					driver->driver.name);
-			}
-		} else {
-			list_for_each_safe(item2, _n, &adap->clients) {
-				client = list_entry(item2, struct i2c_client, list);
-				if (client->driver != driver)
-					continue;
-				dev_dbg(&adap->dev, "detaching client [%s] "
-					"at 0x%02x\n", client->name,
-					client->addr);
-				if (driver->detach_client(client)) {
-					dev_err(&adap->dev, "detach_client "
-						"failed for client [%s] at "
-						"0x%02x\n", client->name,
-						client->addr);
-				}
-			}
-		}
-	}
-	up(&i2c_adapter_class.sem);
+	class_for_each_device(&i2c_adapter_class, driver, __detach_adapter);
 
  unregister:
 	driver_unregister(&driver->driver);
-- 
2.39.2