Commit c4804670 authored by M Chetan Kumar's avatar M Chetan Kumar Committed by David S. Miller
Browse files

net: wwan: common debugfs base dir for wwan device 



This patch set brings in a common debugfs base directory
i.e. /sys/kernel/debugfs/wwan/ in WWAN Subsystem for a
WWAN device instance. So that it avoids driver polluting
debugfs root with unrelated directories & possible name
collusion.

Having a common debugfs base directory for WWAN drivers
eases user to match control devices with debugfs entries.

WWAN Subsystem creates dentry (/sys/kernel/debugfs/wwan)
on module load & removes dentry on module unload.

When driver registers a new wwan device, dentry (wwanX)
is created for WWAN device instance & on driver unregister
dentry is removed.

New API is introduced to return the wwan device instance
dentry so that driver can create debugfs entries under it.

Signed-off-by: default avatarM Chetan Kumar <m.chetan.kumar@linux.intel.com>
Reviewed-by: default avatarLoic Poulain <loic.poulain@linaro.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a9c2cf9e

drivers/net/wwan/wwan_core.c

+28 −2
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 


#include <linux/err.h>

#include <linux/errno.h>

#include <linux/debugfs.h>

#include <linux/fs.h>

#include <linux/init.h>

#include <linux/idr.h>
@@ -25,6 +26,7 @@ static DEFINE_IDA(minors); /* minors for WWAN port chardevs */ 
static DEFINE_IDA(wwan_dev_ids); /* for unique WWAN device IDs */

static struct class *wwan_class;

static int wwan_major;

static struct dentry *wwan_debugfs_dir;



#define to_wwan_dev(d) container_of(d, struct wwan_device, dev)

#define to_wwan_port(d) container_of(d, struct wwan_port, dev)
@@ -40,6 +42,7 @@ static int wwan_major; 
 * @port_id: Current available port ID to pick.

 * @ops: wwan device ops

 * @ops_ctxt: context to pass to ops

 * @debugfs_dir:  WWAN device debugfs dir

 */

struct wwan_device {

	unsigned int id;
@@ -47,6 +50,7 @@ struct wwan_device { 
	atomic_t port_id;

	const struct wwan_ops *ops;

	void *ops_ctxt;

	struct dentry *debugfs_dir;

};



/**
@@ -142,6 +146,18 @@ static struct wwan_device *wwan_dev_get_by_name(const char *name) 
	return to_wwan_dev(dev);

}



struct dentry *wwan_get_debugfs_dir(struct device *parent)

{

	struct wwan_device *wwandev;



	wwandev = wwan_dev_get_by_parent(parent);

	if (IS_ERR(wwandev))

		return ERR_CAST(wwandev);



	return wwandev->debugfs_dir;

}

EXPORT_SYMBOL_GPL(wwan_get_debugfs_dir);



/* This function allocates and registers a new WWAN device OR if a WWAN device

 * already exist for the given parent, it gets a reference and return it.

 * This function is not exported (for now), it is called indirectly via
@@ -150,6 +166,7 @@ static struct wwan_device *wwan_dev_get_by_name(const char *name) 
static struct wwan_device *wwan_create_dev(struct device *parent)

{

	struct wwan_device *wwandev;

	const char *wwandev_name;

	int err, id;



	/* The 'find-alloc-register' operation must be protected against
@@ -189,6 +206,10 @@ static struct wwan_device *wwan_create_dev(struct device *parent) 
		goto done_unlock;

	}



	wwandev_name = kobject_name(&wwandev->dev.kobj);

	wwandev->debugfs_dir = debugfs_create_dir(wwandev_name,

						  wwan_debugfs_dir);



done_unlock:

	mutex_unlock(&wwan_register_lock);
@@ -218,10 +239,12 @@ static void wwan_remove_dev(struct wwan_device *wwandev) 
	else

		ret = device_for_each_child(&wwandev->dev, NULL, is_wwan_child);



	if (!ret)

	if (!ret) {

		debugfs_remove_recursive(wwandev->debugfs_dir);

		device_unregister(&wwandev->dev);

	else

	} else {

		put_device(&wwandev->dev);

	}



	mutex_unlock(&wwan_register_lock);

}
@@ -1117,6 +1140,8 @@ static int __init wwan_init(void) 
		goto destroy;

	}



	wwan_debugfs_dir = debugfs_create_dir("wwan", NULL);



	return 0;



destroy:
@@ -1128,6 +1153,7 @@ static int __init wwan_init(void) 


static void __exit wwan_exit(void)

{

	debugfs_remove_recursive(wwan_debugfs_dir);

	__unregister_chrdev(wwan_major, 0, WWAN_MAX_MINORS, "wwan_port");

	rtnl_link_unregister(&wwan_rtnl_link_ops);

	class_destroy(wwan_class);

include/linux/wwan.h

+2 −0
Original line number Diff line number Diff line
@@ -171,4 +171,6 @@ int wwan_register_ops(struct device *parent, const struct wwan_ops *ops, 


void wwan_unregister_ops(struct device *parent);



struct dentry *wwan_get_debugfs_dir(struct device *parent);



#endif /* __WWAN_H */