[PATCH] iio: core: fail early in iio_device_alloc() if we can't get a device id

[Alexandru Ardelean]

This change moves the 'ida_simple_get()' call to be the first one in
iio_device_alloc(). It cleans up the error path a bit as we don't need to
call any kfree(dev) anymore. We allocate an IIO device only if we have
managed to obtain a device ID.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
---
 drivers/iio/industrialio-core.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index f4daf19f2a3b..7c1d8a3ab2f3 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1494,6 +1494,14 @@ struct iio_dev *iio_device_alloc(int sizeof_priv)
 {
 	struct iio_dev *dev;
 	size_t alloc_size;
+	int id;
+
+	id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
+	if (id < 0) {
+		/* cannot use a dev_err as the name isn't available */
+		pr_err("failed to get device id\n");
+		return NULL;
+	}
 
 	alloc_size = sizeof(struct iio_dev);
 	if (sizeof_priv) {
@@ -1506,6 +1514,8 @@ struct iio_dev *iio_device_alloc(int sizeof_priv)
 	dev = kzalloc(alloc_size, GFP_KERNEL);
 
 	if (dev) {
+		dev->id = id;
+		dev_set_name(&dev->dev, "iio:device%d", dev->id);
 		dev->dev.groups = dev->groups;
 		dev->dev.type = &iio_device_type;
 		dev->dev.bus = &iio_bus_type;
@@ -1514,15 +1524,6 @@ struct iio_dev *iio_device_alloc(int sizeof_priv)
 		mutex_init(&dev->mlock);
 		mutex_init(&dev->info_exist_lock);
 		INIT_LIST_HEAD(&dev->channel_attr_list);
-
-		dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
-		if (dev->id < 0) {
-			/* cannot use a dev_err as the name isn't available */
-			pr_err("failed to get device id\n");
-			kfree(dev);
-			return NULL;
-		}
-		dev_set_name(&dev->dev, "iio:device%d", dev->id);
 		INIT_LIST_HEAD(&dev->buffer_list);
 	}
 
-- 
2.17.1