iio: Avoid unnecessary kasprintf

name_format already contains the final name and no format characters. So the
code basically reads:

	dev_attr->attr.name = kstrdup(GFP_KERNEL, name_format);
	if (dev_attr->attr.name == NULL)
		...
	kfree(name_format);

Which means we can save one alloc and free pair per attribute name if we
directly assign name_format to dev_attr->attr.name.

The patch also renames name_format to name to denote that this is indeed the
final name and has no format characters in it.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

1 files changed, 13 insertions, 26 deletions

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 39fb8cc46373..ede16aec20fb 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -540,7 +540,7 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
                            enum iio_shared_by shared_by)
 {
         int ret = 0;
-        char *name_format = NULL;
+        char *name = NULL;
         char *full_postfix;
         sysfs_attr_init(&dev_attr->attr);
 
@@ -572,16 +572,15 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
         if (chan->differential) { /* Differential can not have modifier */
                 switch (shared_by) {
                 case IIO_SHARED_BY_ALL:
-                        name_format = kasprintf(GFP_KERNEL, "%s", full_postfix);
+                        name = kasprintf(GFP_KERNEL, "%s", full_postfix);
                         break;
                 case IIO_SHARED_BY_DIR:
-                        name_format = kasprintf(GFP_KERNEL, "%s_%s",
+                        name = kasprintf(GFP_KERNEL, "%s_%s",
                                                 iio_direction[chan->output],
                                                 full_postfix);
                         break;
                 case IIO_SHARED_BY_TYPE:
-                        name_format
-                                = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
+                        name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
                                             iio_direction[chan->output],
                                             iio_chan_type_name_spec[chan->type],
                                             iio_chan_type_name_spec[chan->type],
@@ -593,8 +592,7 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
                                 ret = -EINVAL;
                                 goto error_free_full_postfix;
                         }
-                        name_format
-                                = kasprintf(GFP_KERNEL,
+                        name = kasprintf(GFP_KERNEL,
                                             "%s_%s%d-%s%d_%s",
                                             iio_direction[chan->output],
                                             iio_chan_type_name_spec[chan->type],
@@ -607,16 +605,15 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
         } else { /* Single ended */
                 switch (shared_by) {
                 case IIO_SHARED_BY_ALL:
-                        name_format = kasprintf(GFP_KERNEL, "%s", full_postfix);
+                        name = kasprintf(GFP_KERNEL, "%s", full_postfix);
                         break;
                 case IIO_SHARED_BY_DIR:
-                        name_format = kasprintf(GFP_KERNEL, "%s_%s",
+                        name = kasprintf(GFP_KERNEL, "%s_%s",
                                                 iio_direction[chan->output],
                                                 full_postfix);
                         break;
                 case IIO_SHARED_BY_TYPE:
-                        name_format
-                                = kasprintf(GFP_KERNEL, "%s_%s_%s",
+                        name = kasprintf(GFP_KERNEL, "%s_%s_%s",
                                             iio_direction[chan->output],
                                             iio_chan_type_name_spec[chan->type],
                                             full_postfix);
@@ -624,33 +621,24 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 
                 case IIO_SEPARATE:
                         if (chan->indexed)
-                                name_format
-                                        = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
+                                name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
                                                     iio_direction[chan->output],
                                                     iio_chan_type_name_spec[chan->type],
                                                     chan->channel,
                                                     full_postfix);
                         else
-                                name_format
-                                        = kasprintf(GFP_KERNEL, "%s_%s_%s",
+                                name = kasprintf(GFP_KERNEL, "%s_%s_%s",
                                                     iio_direction[chan->output],
                                                     iio_chan_type_name_spec[chan->type],
                                                     full_postfix);
                         break;
                 }
         }
-        if (name_format == NULL) {
+        if (name == NULL) {
                 ret = -ENOMEM;
                 goto error_free_full_postfix;
         }
-        dev_attr->attr.name = kasprintf(GFP_KERNEL,
-                                        name_format,
-                                        chan->channel,
-                                        chan->channel2);
-        if (dev_attr->attr.name == NULL) {
-                ret = -ENOMEM;
-                goto error_free_name_format;
-        }
+        dev_attr->attr.name = name;
 
         if (readfunc) {
                 dev_attr->attr.mode |= S_IRUGO;
@@ -661,8 +649,7 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
                 dev_attr->attr.mode |= S_IWUSR;
                 dev_attr->store = writefunc;
         }
-error_free_name_format:
-        kfree(name_format);
+
 error_free_full_postfix:
         kfree(full_postfix);