scripts: Coccinelle script for pm_runtime_* return checks with IS_ERR_VALUE

As indicated by Sekhar in [1], there seems to be a tendency to use
IS_ERR_VALUE to check the error result for pm_runtime_* functions which
make no sense considering commit c48cd659 (ARM: OMAP: use consistent
error checking) - the error values can either be < 0 for error OR
0, 1 in cases where we have success.

So, setup a coccinelle script to help identify the same.

[1] http://marc.info/?t=138472678100003&r=1&w=2

Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Reported-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>

scripts/coccinelle/api/pm_runtime.cocci

+/// Make sure pm_runtime_* calls does not use unnecessary IS_ERR_VALUE
+//
+// Keywords: pm_runtime
+// Confidence: Medium
+// Copyright (C) 2013 Texas Instruments Incorporated - GPLv2.
+// URL: http://coccinelle.lip6.fr/
+// Options: --include-headers
+
+virtual patch
+virtual context
+virtual org
+virtual report
+
+//----------------------------------------------------------
+//  Detection
+//----------------------------------------------------------
+
+@runtime_bad_err_handle exists@
+expression ret;
+@@
+(
+ret = \(pm_runtime_idle\|
+	pm_runtime_suspend\|
+	pm_runtime_autosuspend\|
+	pm_runtime_resume\|
+	pm_request_idle\|
+	pm_request_resume\|
+	pm_request_autosuspend\|
+	pm_runtime_get\|
+	pm_runtime_get_sync\|
+	pm_runtime_put\|
+	pm_runtime_put_autosuspend\|
+	pm_runtime_put_sync\|
+	pm_runtime_put_sync_suspend\|
+	pm_runtime_put_sync_autosuspend\|
+	pm_runtime_set_active\|
+	pm_schedule_suspend\|
+	pm_runtime_barrier\|
+	pm_generic_runtime_suspend\|
+	pm_generic_runtime_resume\)(...);
+...
+IS_ERR_VALUE(ret)
+...
+)
+
+//----------------------------------------------------------
+//  For context mode
+//----------------------------------------------------------
+
+@depends on runtime_bad_err_handle && context@
+identifier pm_runtime_api;
+expression ret;
+@@
+(
+ret = pm_runtime_api(...);
+...
+* IS_ERR_VALUE(ret)
+...
+)
+
+//----------------------------------------------------------
+//  For patch mode
+//----------------------------------------------------------
+
+@depends on runtime_bad_err_handle && patch@
+identifier pm_runtime_api;
+expression ret;
+@@
+(
+ret = pm_runtime_api(...);
+...
+- IS_ERR_VALUE(ret)
++ ret < 0
+...
+)
+
+//----------------------------------------------------------
+//  For org and report mode
+//----------------------------------------------------------
+
+@r depends on runtime_bad_err_handle exists@
+position p1, p2;
+identifier pm_runtime_api;
+expression ret;
+@@
+(
+ret = pm_runtime_api@p1(...);
+...
+IS_ERR_VALUE@p2(ret)
+...
+)
+
+@script:python depends on org@
+p1 << r.p1;
+p2 << r.p2;
+pm_runtime_api << r.pm_runtime_api;
+@@
+
+cocci.print_main(pm_runtime_api,p1)
+cocci.print_secs("IS_ERR_VALUE",p2)
+
+@script:python depends on report@
+p1 << r.p1;
+p2 << r.p2;
+pm_runtime_api << r.pm_runtime_api;
+@@
+
+msg = "%s returns < 0 as error. Unecessary IS_ERR_VALUE at line %s" % (pm_runtime_api, p2[0].line)
+coccilib.report.print_report(p1[0],msg)