A straightforward looking use of idr for a device id.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Acked-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/drivers/hwmon/ibmaem.c b/drivers/hwmon/ibmaem.c
index c6d59b1788d7d835b901297a93fdf8dcb737504f..6a967d7dbdee845d653ec3cac19d84ba872e4363 100644 (file)
--- a/drivers/hwmon/ibmaem.c
+++ b/drivers/hwmon/ibmaem.c
@@ -88,8 +88,7 @@
 #define AEM_MIN_POWER_INTERVAL 200
 #define UJ_PER_MJ              1000L
 
-static DEFINE_IDR(aem_idr);
-static DEFINE_SPINLOCK(aem_idr_lock);
+static DEFINE_IDA(aem_ida);
 
 static struct platform_driver aem_driver = {
        .driver = {
@@ -355,38 +354,6 @@ static void aem_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
        complete(&data->read_complete);
 }
 
-/* ID functions */
-
-/* Obtain an id */
-static int aem_idr_get(int *id)
-{
-       int i, err;
-
-again:
-       if (unlikely(!idr_pre_get(&aem_idr, GFP_KERNEL)))
-               return -ENOMEM;
-
-       spin_lock(&aem_idr_lock);
-       err = idr_get_new(&aem_idr, NULL, &i);
-       spin_unlock(&aem_idr_lock);
-
-       if (unlikely(err == -EAGAIN))
-               goto again;
-       else if (unlikely(err))
-               return err;
-
-       *id = i & MAX_ID_MASK;
-       return 0;
-}
-
-/* Release an object ID */
-static void aem_idr_put(int id)
-{
-       spin_lock(&aem_idr_lock);
-       idr_remove(&aem_idr, id);
-       spin_unlock(&aem_idr_lock);
-}
-
 /* Sensor support functions */
 
 /* Read a sensor value; must be called with data->lock held */
@@ -526,7 +493,7 @@ static void aem_delete(struct aem_data *data)
        ipmi_destroy_user(data->ipmi.user);
        platform_set_drvdata(data->pdev, NULL);
        platform_device_unregister(data->pdev);
-       aem_idr_put(data->id);
+       ida_simple_remove(&aem_ida, data->id);
        kfree(data);
 }
 
@@ -583,7 +550,8 @@ static int aem_init_aem1_inst(struct aem_ipmi_data *probe, u8 module_handle)
                data->power_period[i] = AEM_DEFAULT_POWER_INTERVAL;
 
        /* Create sub-device for this fw instance */
-       if (aem_idr_get(&data->id))
+       data->id = ida_simple_get(&aem_ida, 0, 0, GFP_KERNEL);
+       if (data->id < 0)
                goto id_err;
 
        data->pdev = platform_device_alloc(DRVNAME, data->id);
@@ -643,7 +611,7 @@ ipmi_err:
        platform_set_drvdata(data->pdev, NULL);
        platform_device_unregister(data->pdev);
 dev_err:
-       aem_idr_put(data->id);
+       ida_simple_remove(&aem_ida, data->id);
 id_err:
        kfree(data);
 
@@ -722,7 +690,8 @@ static int aem_init_aem2_inst(struct aem_ipmi_data *probe,
                data->power_period[i] = AEM_DEFAULT_POWER_INTERVAL;
 
        /* Create sub-device for this fw instance */
-       if (aem_idr_get(&data->id))
+       data->id = ida_simple_get(&aem_ida, 0, 0, GFP_KERNEL);
+       if (data->id < 0)
                goto id_err;
 
        data->pdev = platform_device_alloc(DRVNAME, data->id);
@@ -782,7 +751,7 @@ ipmi_err:
        platform_set_drvdata(data->pdev, NULL);
        platform_device_unregister(data->pdev);
 dev_err:
-       aem_idr_put(data->id);
+       ida_simple_remove(&aem_ida, data->id);
 id_err:
        kfree(data);