[PATCH v2 2/4] of: overlay: kobjectify overlay objects

Pantelis Antoniou
2015-04-07T19:24:10Z

We are going to need the overlays to appear on sysfs with runtime
global properties (like master enable) so turn them into kobjects.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
---
drivers/of/base.c | 5 +++++
drivers/of/of_private.h | 9 +++++++++
drivers/of/overlay.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++--
3 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 69566b6..808f351 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -192,6 +192,7 @@ int __of_attach_node_sysfs(struct device_node *np)
static int __init of_init(void)
{
struct device_node *np;
+ int ret;

/* Create the kset, and register existing nodes */
mutex_lock(&of_mutex);
@@ -208,6 +209,10 @@ static int __init of_init(void)
if (of_root)
proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");

+ ret = of_overlay_init();
+ if (ret != 0)
+ pr_warn("of_init: of_overlay_init failed!\n");
+
return 0;
}
core_initcall(of_init);
diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index 8e882e7..120eb44 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -90,4 +90,13 @@ extern void __of_detach_node_sysfs(struct device_node *np);
#define for_each_transaction_entry_reverse(_oft, _te) \
list_for_each_entry_reverse(_te, &(_oft)->te_list, node)

+#if defined(CONFIG_OF_OVERLAY)
+extern int of_overlay_init(void);
+#else
+static inline int of_overlay_init(void)
+{
+ return 0;
+}
+#endif
+
#endif /* _LINUX_OF_PRIVATE_H */
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
index dee9270..f17f5ef 100644
--- a/drivers/of/overlay.c
+++ b/drivers/of/overlay.c
@@ -20,6 +20,7 @@
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/idr.h>
+#include <linux/sysfs.h>

#include "of_private.h"

@@ -51,6 +52,7 @@ struct of_overlay {
int count;
struct of_overlay_info *ovinfo_tab;
struct of_changeset cset;
+ struct kobject kobj;
};

static int of_overlay_apply_one(struct of_overlay *ov,
@@ -325,6 +327,24 @@ static int of_free_overlay_info(struct of_overlay *ov)
static LIST_HEAD(ov_list);
static DEFINE_IDR(ov_idr);

+static inline struct of_overlay *kobj_to_overlay(struct kobject *kobj)
+{
+ return container_of(kobj, struct of_overlay, kobj);
+}
+
+void of_overlay_release(struct kobject *kobj)
+{
+ struct of_overlay *ov = kobj_to_overlay(kobj);
+
+ kfree(ov);
+}
+
+static struct kobj_type of_overlay_ktype = {
+ .release = of_overlay_release,
+};
+
+static struct kset *ov_kset;
+
/**
* of_overlay_create() - Create and apply an overlay
* @tree: Device node containing all the overlays
@@ -350,6 +370,9 @@ int of_overlay_create(struct device_node *tree)

of_changeset_init(&ov->cset);

+ /* initialize kobject */
+ kobject_init(&ov->kobj, &of_overlay_ktype);
+
mutex_lock(&of_mutex);

id = idr_alloc(&ov_idr, ov, 0, 0, GFP_KERNEL);
@@ -385,6 +408,14 @@ int of_overlay_create(struct device_node *tree)
goto err_revert_overlay;
}

+ ov->kobj.kset = ov_kset;
+ err = kobject_add(&ov->kobj, NULL, "%d", id);
+ if (err != 0) {
+ pr_err("%s: kobject_add() failed for tree@%s\n",
+ __func__, tree->full_name);
+ goto err_cancel_overlay;
+ }
+
/* add to the tail of the overlay list */
list_add_tail(&ov->node, &ov_list);

@@ -392,6 +423,8 @@ int of_overlay_create(struct device_node *tree)

return id;

+err_cancel_overlay:
+ of_changeset_revert(&ov->cset);
err_revert_overlay:
err_abort_trans:
of_free_overlay_info(ov);
@@ -512,7 +545,9 @@ int of_overlay_destroy(int id)
of_free_overlay_info(ov);
idr_remove(&ov_idr, id);
of_changeset_destroy(&ov->cset);
- kfree(ov);
+
+ kobject_del(&ov->kobj);
+ kobject_put(&ov->kobj);

err = 0;

@@ -542,7 +577,8 @@ int of_overlay_destroy_all(void)
of_changeset_revert(&ov->cset);
of_free_overlay_info(ov);
idr_remove(&ov_idr, ov->id);
- kfree(ov);
+ kobject_del(&ov->kobj);
+ kobject_put(&ov->kobj);
}

mutex_unlock(&of_mutex);
@@ -550,3 +586,15 @@ int of_overlay_destroy_all(void)
return 0;
}
EXPORT_SYMBOL_GPL(of_overlay_destroy_all);
+
+/* called from of_init() */
+int of_overlay_init(void)
+{
+ int rc;
+
+ ov_kset = kset_create_and_add("overlays", NULL, &of_kset->kobj);
+ if (!ov_kset)
+ return -ENOMEM;
+
+ return 0;
+}
--
1.7.12