[v2] coccinelle: api: Don't use devm_platform_get_and_ioremap_resource with res==NULL

Message ID 20221107181135.tm2wmwiulepsyrmk@pengutronix.de
State New
Headers
Series [v2] coccinelle: api: Don't use devm_platform_get_and_ioremap_resource with res==NULL |

Commit Message

Uwe Kleine-König Nov. 7, 2022, 6:11 p.m. UTC
  devm_platform_get_and_ioremap_resource(pdev, index, NULL) is equivalent to
the shorter devm_platform_ioremap_resource(pdev, index).

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
On Mon, Nov 07, 2022 at 08:45:38PM +0800, Julia Lawall wrote:
> On Mon, 7 Nov 2022, Uwe Kleine-König wrote:
> 
> > devm_platform_get_and_ioremap_resource(pdev, index, NULL) is equivalent to
> > the shorter devm_platform_ioremap_resource(pdev, index).
> >
> > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> > ---
> > Hello,
> >
> > a potential improvement is to check for invocations of
> > devm_platform_get_and_ioremap_resource() where the res parameter isn't
> > used afterwards, but my coccinelle foo isn't strong enough for that.
> 
> ... when != res
> 
> I'm not sure where you wanted to put it though.

I tinkered a bit further and even succeeded to remove the declaration if
it's otherwise unused.

I failed to test the report mode, my spatch tells me some error about
python2?!

Best regards
Uwe

 .../api/devm_platform_ioremap_resource.cocci  | 85 +++++++++++++++++++
 1 file changed, 85 insertions(+)
 create mode 100644 scripts/coccinelle/api/devm_platform_ioremap_resource.cocci
  

Comments

Uwe Kleine-König Nov. 10, 2022, 3:07 p.m. UTC | #1
Hello,

On Mon, Nov 07, 2022 at 07:11:35PM +0100, Uwe Kleine-König wrote:
> devm_platform_get_and_ioremap_resource(pdev, index, NULL) is equivalent to
> the shorter devm_platform_ioremap_resource(pdev, index).
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> ---
> On Mon, Nov 07, 2022 at 08:45:38PM +0800, Julia Lawall wrote:
> > On Mon, 7 Nov 2022, Uwe Kleine-König wrote:
> > 
> > > devm_platform_get_and_ioremap_resource(pdev, index, NULL) is equivalent to
> > > the shorter devm_platform_ioremap_resource(pdev, index).
> > >
> > > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> > > ---
> > > Hello,
> > >
> > > a potential improvement is to check for invocations of
> > > devm_platform_get_and_ioremap_resource() where the res parameter isn't
> > > used afterwards, but my coccinelle foo isn't strong enough for that.
> > 
> > ... when != res
> > 
> > I'm not sure where you wanted to put it though.
> 
> I tinkered a bit further and even succeeded to remove the declaration if
> it's otherwise unused.
> 
> I failed to test the report mode, my spatch tells me some error about
> python2?!

For the record, that is a problem with Debian's coccinelle, bugreport 
at https://bugs.debian.org/1023653

Best regards
Uwe
  

Patch

diff --git a/scripts/coccinelle/api/devm_platform_ioremap_resource.cocci b/scripts/coccinelle/api/devm_platform_ioremap_resource.cocci
new file mode 100644
index 000000000000..485dfa6ea0aa
--- /dev/null
+++ b/scripts/coccinelle/api/devm_platform_ioremap_resource.cocci
@@ -0,0 +1,85 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/// Don't use devm_platform_get_and_ioremap_resource with NULL as third parameter
+// Confidence: High
+
+virtual patch
+virtual context
+virtual org
+virtual report
+
+@r1@
+position p;
+@@
+ devm_platform_ioremap_resource(...) {
+	...
+	devm_platform_get_and_ioremap_resource@p(...)
+	...
+ }
+
+@depends on patch@
+expression pdev,index;
+position p != r1.p;
+@@
+
+-  devm_platform_get_and_ioremap_resource@p(pdev, index, NULL)
++  devm_platform_ioremap_resource(pdev, index)
+
+@depends on patch@
+expression pdev,index;
+identifier res;
+type T;
+@@
+-  T res;
+   ... when != res
+-  devm_platform_get_and_ioremap_resource(pdev, index, &res)
++  devm_platform_ioremap_resource(pdev, index)
+   ... when != res
+
+@depends on patch@
+expression pdev,index;
+identifier res;
+@@
+
+-  devm_platform_get_and_ioremap_resource(pdev, index, &res)
++  devm_platform_ioremap_resource(pdev, index)
+   ... when != res
+
+@r2 depends on !patch exists@
+expression pdev,index;
+position p;
+@@
+
+*  devm_platform_get_and_ioremap_resource@p(pdev, index, NULL)
+
+@script:python depends on org@
+p << r2.p;
+@@
+
+cocci.print_main("WARNING opportunity for devm_platform_ioremap_resource", p)
+
+@script:python depends on report@
+p << r2.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for devm_platform_ioremap_resource")
+
+@r3 depends on !patch exists@
+expression pdev,index;
+identifier res;
+position p;
+@@
+
+*  devm_platform_get_and_ioremap_resource@p(pdev, index, &res)
+   ... when != res
+
+@script:python depends on org@
+p << r3.p;
+@@
+
+cocci.print_main("WARNING opportunity for devm_platform_ioremap_resource", p)
+
+@script:python depends on report@
+p << r3.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for devm_platform_ioremap_resource")