dmascc: Return correct error codes

This change has been made with the goal that kernel functions should
return something more descriptive than -1 on failure.

A variable `err` has been introduced for storing error codes.

The return value of kzalloc on failure should return a -1 and not a
-ENOMEM. This was found using Coccinelle. A simplified version of
the semantic patch used is:

//<smpl>
@@
expression *e;
identifier l1;
@@

e = kzalloc(...);
if (e == NULL) {
...
goto l1;
}
l1:
...
return -1
+ -ENOMEM
;
//</smpl

Furthermore, set `err` to -ENOMEM on failure of alloc_netdev(), and to
-ENODEV on failure of register_netdev() and probe_irq_off().

The single call site only checks that the return value is not 0,
hence no change is required at the call site.

Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/net/hamradio/dmascc.c b/drivers/net/hamradio/dmascc.c
index c3d377770616..e4137c1b3df9 100644
--- a/drivers/net/hamradio/dmascc.c
+++ b/drivers/net/hamradio/dmascc.c
@@ -451,7 +451,7 @@ static const struct net_device_ops scc_netdev_ops = {
 
 static int __init setup_adapter(int card_base, int type, int n)
 {
-        int i, irq, chip;
+        int i, irq, chip, err;
         struct scc_info *info;
         struct net_device *dev;
         struct scc_priv *priv;
@@ -463,14 +463,17 @@ static int __init setup_adapter(int card_base, int type, int n)
 
         /* Initialize what is necessary for write_scc and write_scc_data */
         info = kzalloc(sizeof(struct scc_info), GFP_KERNEL | GFP_DMA);
-        if (!info)
+        if (!info) {
+                err = -ENOMEM;
                 goto out;
+        }
 
         info->dev[0] = alloc_netdev(0, "", NET_NAME_UNKNOWN, dev_setup);
         if (!info->dev[0]) {
                 printk(KERN_ERR "dmascc: "
                        "could not allocate memory for %s at %#3x\n",
                        hw[type].name, card_base);
+                err = -ENOMEM;
                 goto out1;
         }
 
@@ -479,6 +482,7 @@ static int __init setup_adapter(int card_base, int type, int n)
                 printk(KERN_ERR "dmascc: "
                        "could not allocate memory for %s at %#3x\n",
                        hw[type].name, card_base);
+                err = -ENOMEM;
                 goto out2;
         }
         spin_lock_init(&info->register_lock);
@@ -549,6 +553,7 @@ static int __init setup_adapter(int card_base, int type, int n)
                 printk(KERN_ERR
                        "dmascc: could not find irq of %s at %#3x (irq=%d)\n",
                        hw[type].name, card_base, irq);
+                err = -ENODEV;
                 goto out3;
         }
 
@@ -585,11 +590,13 @@ static int __init setup_adapter(int card_base, int type, int n)
         if (register_netdev(info->dev[0])) {
                 printk(KERN_ERR "dmascc: could not register %s\n",
                        info->dev[0]->name);
+                err = -ENODEV;
                 goto out3;
         }
         if (register_netdev(info->dev[1])) {
                 printk(KERN_ERR "dmascc: could not register %s\n",
                        info->dev[1]->name);
+                err = -ENODEV;
                 goto out4;
         }
 
@@ -612,7 +619,7 @@ static int __init setup_adapter(int card_base, int type, int n)
       out1:
         kfree(info);
       out:
-        return -1;
+        return err;
 }