display7seg: Introduce the use of the managed version of kzalloc

This patch moves data allocated using kzalloc to managed data allocated using devm_kzalloc and cleans now unnecessary kfrees in probe and remove functions. The header file is added to make the devm function explicitly available.

The following Coccinelle semantic patch was used for making a part of the change:

@platform@
identifier p, probefn, removefn;
@@
struct platform_driver p = {
.probe = probefn,
.remove = removefn,
};

@prb@
identifier platform.probefn, pdev;
expression e, e1, e2;
@@
probefn(struct platform_device *pdev, ...) {
<+...
- e = kzalloc(e1, e2)
+ e = devm_kzalloc(&pdev->dev, e1, e2)
...
?-kfree(e);
...+>
}

@rem depends on prb@
identifier platform.removefn;
expression e;
@@
removefn(...) {
<...
- kfree(e);
...>
}

---
Not compile tested due to incompatible architecture.

 drivers/sbus/char/display7seg.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

index 7c71e7b..b48899c 100644
@@ -4,6 +4,7 @@
  * Copyright (c) 2000 Eric Brower ([email protected])
  */
 
+#include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/fs.h>

@@ -180,7 +181,7 @@ static int d7s_probe(struct platform_device *op)
 	if (d7s_device)
 		goto out;
 
-	p = kzalloc(sizeof(*p), GFP_KERNEL);
+	p = devm_kzalloc(&op->dev, sizeof(*p), GFP_KERNEL);
 	err = -ENOMEM;
 	if (!p)
 		goto out;

@@ -231,7 +232,6 @@ out_iounmap:
 	of_iounmap(&op->resource[0], p->regs, sizeof(u8));
 
 out_free:
-	kfree(p);
 	goto out;
 }
 

@@ -251,7 +251,6 @@ static int d7s_remove(struct platform_device *op)
 
 	misc_deregister(&d7s_miscdev);
 	of_iounmap(&op->resource[0], p->regs, sizeof(u8));
-	kfree(p);
 
 	return 0;
 }

1.9.1

From: Himangi Saraogi <[email protected]>
Date: Tue, 27 May 2014 03:02:07 +0530

...

Applied to sparc-next.