patch-2_6_7-vs1_9_1_12

[linux-2.6.git] / drivers / i2c / i2c-core.c

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 8663e1b..56225a5 100644 (file)
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -28,6 +28,7 @@
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/init.h>
+#include <linux/idr.h>
 #include <linux/seq_file.h>
 #include <asm/uaccess.h>
 
@@ -35,6 +36,7 @@
 static LIST_HEAD(adapters);
 static LIST_HEAD(drivers);
 static DECLARE_MUTEX(core_lists);
+static DEFINE_IDR(i2c_adapter_idr);
 
 int i2c_device_probe(struct device *dev)
 {
@@ -113,13 +115,19 @@ static struct device_attribute dev_attr_client_name = {
  */
 int i2c_add_adapter(struct i2c_adapter *adap)
 {
-       static int nr = 0;
+       int id, res = 0;
        struct list_head   *item;
        struct i2c_driver  *driver;
 
        down(&core_lists);
 
-       adap->nr = nr++;
+       if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) {
+               res = -ENOMEM;
+               goto out_unlock;
+       }
+
+       id = idr_get_new(&i2c_adapter_idr, NULL);
+       adap->nr =  id & MAX_ID_MASK;
        init_MUTEX(&adap->bus_lock);
        init_MUTEX(&adap->clist_lock);
        list_add_tail(&adap->list,&adapters);
@@ -151,10 +159,12 @@ int i2c_add_adapter(struct i2c_adapter *adap)
                        /* We ignore the return code; if it fails, too bad */
                        driver->attach_adapter(adap);
        }
-       up(&core_lists);
 
        dev_dbg(&adap->dev, "registered as adapter #%d\n", adap->nr);
-       return 0;
+
+ out_unlock:
+       up(&core_lists);
+       return res;
 }
 
 
@@ -208,6 +218,9 @@ int i2c_del_adapter(struct i2c_adapter *adap)
        wait_for_completion(&adap->dev_released);
        wait_for_completion(&adap->class_dev_released);
 
+       /* free dynamically allocated bus id */
+       idr_remove(&i2c_adapter_idr, adap->nr);
+
        dev_dbg(&adap->dev, "adapter unregistered\n");
 
  out_unlock: