@@ -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 +146,22 @@ 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;
+
+ if (WARN_ON(!parent))
+ return ERR_PTR(-EINVAL);
+
+ 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 +170,7 @@ 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 +210,10 @@ 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 +240,12 @@ 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 +1144,8 @@ static int __init wwan_init(void)
goto destroy;
}
+ wwan_debugfs_dir = debugfs_create_dir("wwan", NULL);
+
return 0;
destroy:
@@ -1128,6 +1157,7 @@ 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);
@@ -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 */
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: M Chetan Kumar <m.chetan.kumar@linux.intel.com> --- drivers/net/wwan/wwan_core.c | 35 +++++++++++++++++++++++++++++++++-- include/linux/wwan.h | 2 ++ 2 files changed, 35 insertions(+), 2 deletions(-)