Subject: [PATCH v1 01/12] powerpc/pseries: CMM: Implement release() function for sysfs device

From: David Hildenbrand <[email-masked]>
Date: Thu, 31 Oct 2019 15:29:22 +0100

When unloading the module, one gets
[  548.188594] ------------[ cut here ]------------
[  548.188596] Device 'cmm0' does not have a release() function, it is broken and must be fixed. See Documentation/kobject.txt.
[  548.188622] WARNING: CPU: 0 PID: 19308 at drivers/base/core.c:1244 .device_release+0xcc/0xf0
...

We only have on static fake device. There is nothing to do when
releasing the device (via cmm_exit).

Cc: Benjamin Herrenschmidt <[email-masked]>
Cc: Paul Mackerras <[email-masked]>
Cc: Michael Ellerman <[email-masked]>
Cc: Andrew Morton <[email-masked]>
Cc: Vlastimil Babka <[email-masked]>
Cc: Konstantin Khlebnikov <[email-masked]>
Cc: Allison Randal <[email-masked]>
Cc: Greg Kroah-Hartman <[email-masked]>
Cc: Thomas Gleixner <[email-masked]>
Cc: Arun KS <[email-masked]>
Signed-off-by: David Hildenbrand <[email-masked]>
---
 arch/powerpc/platforms/pseries/cmm.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/cmm.c b/arch/powerpc/platforms/pseries/cmm.c
index b33251d75927..572651a5c87b 100644
--- a/arch/powerpc/platforms/pseries/cmm.c
+++ b/arch/powerpc/platforms/pseries/cmm.c
@@ -411,6 +411,10 @@ static struct bus_type cmm_subsys = {
 	.dev_name = "cmm",
 };
 
+static void cmm_release_device(struct device *dev)
+{
+}
+
 /**
  * cmm_sysfs_register - Register with sysfs
  *
@@ -426,6 +430,7 @@ static int cmm_sysfs_register(struct device *dev)
 
 	dev->id = 0;
 	dev->bus = &cmm_subsys;
+	dev->release = cmm_release_device;
 
 	if ((rc = device_register(dev)))
 		goto subsys_unregister;
-- 
2.21.0