[PATCH] media: pvrusb2: clean up unneeded complexity in pvrusb2 class logic

From: Greg Kroah-Hartman
Date: Wed Mar 29 2023 - 02:01:54 EST


The pvrusb2 driver struct class logic was dynamically creating a class
that should have just been static as it did not do anything special and
was only a wrapper around a stock "struct class" implementation. Clean
this all up by making a static struct class and modifying the code to
correctly reference it.

By doing so, lots of unneeded lines of code were removed, and #ifdef
logic was cleaned up so that the .c files are not cluttered up with
extra complexity following the proper kernel coding style.

Cc: Mike Isely <isely@xxxxxxxxx>
Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Cc: linux-media@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
Note: I would like to take this through the driver-core tree as I have
later struct class cleanups that depend on this change being made to the
tree if that's ok with the maintainer of this file.

drivers/media/usb/pvrusb2/pvrusb2-main.c | 18 ++-----
drivers/media/usb/pvrusb2/pvrusb2-sysfs.c | 59 +++++++----------------
drivers/media/usb/pvrusb2/pvrusb2-sysfs.h | 16 +++---
3 files changed, 29 insertions(+), 64 deletions(-)

diff --git a/drivers/media/usb/pvrusb2/pvrusb2-main.c b/drivers/media/usb/pvrusb2/pvrusb2-main.c
index ce4d566e4e5a..721dafd2c14b 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-main.c
+++ b/drivers/media/usb/pvrusb2/pvrusb2-main.c
@@ -16,9 +16,7 @@
#include "pvrusb2-context.h"
#include "pvrusb2-debug.h"
#include "pvrusb2-v4l2.h"
-#ifdef CONFIG_VIDEO_PVRUSB2_SYSFS
#include "pvrusb2-sysfs.h"
-#endif /* CONFIG_VIDEO_PVRUSB2_SYSFS */

#define DRIVER_AUTHOR "Mike Isely <isely@xxxxxxxxx>"
#define DRIVER_DESC "Hauppauge WinTV-PVR-USB2 MPEG2 Encoder/Tuner"
@@ -36,10 +34,6 @@ int pvrusb2_debug = DEFAULT_DEBUG_MASK;
module_param_named(debug,pvrusb2_debug,int,S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(debug, "Debug trace mask");

-#ifdef CONFIG_VIDEO_PVRUSB2_SYSFS
-static struct pvr2_sysfs_class *class_ptr = NULL;
-#endif /* CONFIG_VIDEO_PVRUSB2_SYSFS */
-
static void pvr_setup_attach(struct pvr2_context *pvr)
{
/* Create association with v4l layer */
@@ -48,9 +42,7 @@ static void pvr_setup_attach(struct pvr2_context *pvr)
/* Create association with dvb layer */
pvr2_dvb_create(pvr);
#endif
-#ifdef CONFIG_VIDEO_PVRUSB2_SYSFS
- pvr2_sysfs_create(pvr,class_ptr);
-#endif /* CONFIG_VIDEO_PVRUSB2_SYSFS */
+ pvr2_sysfs_create(pvr);
}

static int pvr_probe(struct usb_interface *intf,
@@ -115,9 +107,7 @@ static int __init pvr_init(void)
return ret;
}

-#ifdef CONFIG_VIDEO_PVRUSB2_SYSFS
- class_ptr = pvr2_sysfs_class_create();
-#endif /* CONFIG_VIDEO_PVRUSB2_SYSFS */
+ pvr2_sysfs_class_create();

ret = usb_register(&pvr_driver);

@@ -141,9 +131,7 @@ static void __exit pvr_exit(void)

pvr2_context_global_done();

-#ifdef CONFIG_VIDEO_PVRUSB2_SYSFS
- pvr2_sysfs_class_destroy(class_ptr);
-#endif /* CONFIG_VIDEO_PVRUSB2_SYSFS */
+ pvr2_sysfs_class_destroy();

pvr2_trace(PVR2_TRACE_INIT,"pvr_exit complete");
}
diff --git a/drivers/media/usb/pvrusb2/pvrusb2-sysfs.c b/drivers/media/usb/pvrusb2/pvrusb2-sysfs.c
index 3e42e209be37..a8c0b513e58e 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-sysfs.c
+++ b/drivers/media/usb/pvrusb2/pvrusb2-sysfs.c
@@ -66,10 +66,6 @@ struct pvr2_sysfs_ctl_item {
char name[80];
};

-struct pvr2_sysfs_class {
- struct class class;
-};
-
static ssize_t show_name(struct device *class_dev,
struct device_attribute *attr,
char *buf)
@@ -487,15 +483,6 @@ static void pvr2_sysfs_tear_down_controls(struct pvr2_sysfs *sfp)
}


-static void pvr2_sysfs_class_release(struct class *class)
-{
- struct pvr2_sysfs_class *clp;
- clp = container_of(class,struct pvr2_sysfs_class,class);
- pvr2_sysfs_trace("Destroying pvr2_sysfs_class id=%p",clp);
- kfree(clp);
-}
-
-
static void pvr2_sysfs_release(struct device *class_dev)
{
pvr2_sysfs_trace("Releasing class_dev id=%p",class_dev);
@@ -503,6 +490,12 @@ static void pvr2_sysfs_release(struct device *class_dev)
}


+static struct class pvr2_class = {
+ .name = "pvrusb2",
+ .dev_release = pvr2_sysfs_release,
+};
+
+
static void class_dev_destroy(struct pvr2_sysfs *sfp)
{
struct device *dev;
@@ -614,8 +607,7 @@ static ssize_t unit_number_show(struct device *class_dev,
}


-static void class_dev_create(struct pvr2_sysfs *sfp,
- struct pvr2_sysfs_class *class_ptr)
+static void class_dev_create(struct pvr2_sysfs *sfp)
{
struct usb_device *usb_dev;
struct device *class_dev;
@@ -628,7 +620,7 @@ static void class_dev_create(struct pvr2_sysfs *sfp,

pvr2_sysfs_trace("Creating class_dev id=%p",class_dev);

- class_dev->class = &class_ptr->class;
+ class_dev->class = &pvr2_class;

dev_set_name(class_dev, "%s",
pvr2_hdw_get_device_identifier(sfp->channel.hdw));
@@ -753,47 +745,30 @@ static void pvr2_sysfs_internal_check(struct pvr2_channel *chp)
}


-struct pvr2_sysfs *pvr2_sysfs_create(struct pvr2_context *mp,
- struct pvr2_sysfs_class *class_ptr)
+void pvr2_sysfs_create(struct pvr2_context *mp)
{
struct pvr2_sysfs *sfp;
sfp = kzalloc(sizeof(*sfp),GFP_KERNEL);
- if (!sfp) return sfp;
+ if (!sfp)
+ return;
pvr2_trace(PVR2_TRACE_STRUCT,"Creating pvr2_sysfs id=%p",sfp);
pvr2_channel_init(&sfp->channel,mp);
sfp->channel.check_func = pvr2_sysfs_internal_check;

- class_dev_create(sfp,class_ptr);
- return sfp;
+ class_dev_create(sfp);
}


-
-struct pvr2_sysfs_class *pvr2_sysfs_class_create(void)
+void pvr2_sysfs_class_create(void)
{
- struct pvr2_sysfs_class *clp;
- clp = kzalloc(sizeof(*clp),GFP_KERNEL);
- if (!clp) return clp;
- pvr2_sysfs_trace("Creating and registering pvr2_sysfs_class id=%p",
- clp);
- clp->class.name = "pvrusb2";
- clp->class.class_release = pvr2_sysfs_class_release;
- clp->class.dev_release = pvr2_sysfs_release;
- if (class_register(&clp->class)) {
- pvr2_sysfs_trace(
- "Registration failed for pvr2_sysfs_class id=%p",clp);
- kfree(clp);
- clp = NULL;
- }
- return clp;
+ if (class_register(&pvr2_class))
+ pvr2_sysfs_trace("Registration failed for pvr2_sysfs_class");
}


-void pvr2_sysfs_class_destroy(struct pvr2_sysfs_class *clp)
+void pvr2_sysfs_class_destroy(void)
{
- pvr2_sysfs_trace("Unregistering pvr2_sysfs_class id=%p", clp);
- if (clp)
- class_unregister(&clp->class);
+ class_unregister(&pvr2_class);
}


diff --git a/drivers/media/usb/pvrusb2/pvrusb2-sysfs.h b/drivers/media/usb/pvrusb2/pvrusb2-sysfs.h
index ac580ff39b5f..375a5372e95c 100644
--- a/drivers/media/usb/pvrusb2/pvrusb2-sysfs.h
+++ b/drivers/media/usb/pvrusb2/pvrusb2-sysfs.h
@@ -10,13 +10,15 @@
#include <linux/sysfs.h>
#include "pvrusb2-context.h"

-struct pvr2_sysfs;
-struct pvr2_sysfs_class;
+#ifdef CONFIG_VIDEO_PVRUSB2_SYSFS
+void pvr2_sysfs_class_create(void);
+void pvr2_sysfs_class_destroy(void);
+void pvr2_sysfs_create(struct pvr2_context *mp);
+#else
+static inline void pvr2_sysfs_class_create(void) { }
+static inline void pvr2_sysfs_class_destroy(void) { }
+static inline void pvr2_sysfs_create(struct pvr2_context *mp) { }
+#endif

-struct pvr2_sysfs_class *pvr2_sysfs_class_create(void);
-void pvr2_sysfs_class_destroy(struct pvr2_sysfs_class *);
-
-struct pvr2_sysfs *pvr2_sysfs_create(struct pvr2_context *,
- struct pvr2_sysfs_class *);

#endif /* __PVRUSB2_SYSFS_H */
--
2.40.0