Add OF notifier handler needed for creating/destroying platform devices
according to dynamic runtime changes in the DT live tree.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
---
drivers/base/platform.c | 18 +++++++++--
drivers/of/platform.c | 78 +++++++++++++++++++++++++++++++++++++++++++++
include/linux/of_platform.h | 10 ++++++
3 files changed, 103 insertions(+), 3 deletions(-)
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index b2afc29..282bfec 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -1002,10 +1002,22 @@ int __init platform_bus_init(void)
error = device_register(&platform_bus);
if (error)
- return error;
- error = bus_register(&platform_bus_type);
+ goto err_out;
+
+ error = bus_register(&platform_bus_type);
+ if (error)
+ goto err_unreg_dev;
+
+ error = of_platform_register_reconfig_notifier();
if (error)
- device_unregister(&platform_bus);
+ goto err_unreg_bus;
+
+ return 0;
+err_unreg_bus:
+ bus_unregister(&platform_bus_type);
+err_unreg_dev:
+ device_unregister(&platform_bus);
+err_out:
return error;
}
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 3b64d0b..aa8db92 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -546,4 +546,82 @@ void of_platform_depopulate(struct device *parent)
}
EXPORT_SYMBOL_GPL(of_platform_depopulate);
+#ifdef CONFIG_OF_DYNAMIC
+
+static struct notifier_block platform_of_notifier;
+
+static int of_platform_notify(struct notifier_block *nb,
+ unsigned long action, void *arg)
+{
+ struct platform_device *pdev_parent, *pdev;
+ struct device_node *dn;
+ int state;
+ bool children_left;
+
+ state = of_reconfig_get_state_change(action, arg);
+
+ /* no change? */
+ if (state == -1)
+ return NOTIFY_OK;
+
+ switch (action) {
+ case OF_RECONFIG_ATTACH_NODE:
+ case OF_RECONFIG_DETACH_NODE:
+ dn = arg;
+ break;
+ case OF_RECONFIG_ADD_PROPERTY:
+ case OF_RECONFIG_REMOVE_PROPERTY:
+ case OF_RECONFIG_UPDATE_PROPERTY:
+ dn = ((struct of_prop_reconfig *)arg)->dn;
+ break;
+ default:
+ return NOTIFY_OK;
+ }
+
+ if (state) {
+
+ /* verify that the parent is a bus */
+ if (!of_match_node(of_default_bus_match_table, dn->parent))
+ return NOTIFY_OK; /* not for us */
+
+ /* pdev_parent may be NULL when no bus platform device */
+ pdev_parent = of_find_device_by_node(dn->parent);
+ pdev = of_platform_device_create(dn, NULL,
+ pdev_parent ? &pdev_parent->dev : NULL);
+ of_dev_put(pdev_parent);
+
+ if (pdev == NULL) {
+ pr_err("%s: failed to create for '%s'\n",
+ __func__, dn->full_name);
+ /* of_platform_device_create tosses the error code */
+ return notifier_from_errno(-EINVAL);
+ }
+
+ } else {
+
+ /* find our device by node */
+ pdev = of_find_device_by_node(dn);
+ if (pdev == NULL)
+ return NOTIFY_OK; /* no? not meant for us */
+
+ /* unregister takes one ref away */
+ of_platform_device_destroy(&pdev->dev, &children_left);
+
+ /* and put the reference of the find */
+ of_dev_put(pdev);
+
+ }
+
+ return NOTIFY_OK;
+}
+
+int of_platform_register_reconfig_notifier(void)
+{
+ platform_of_notifier.notifier_call = of_platform_notify;
+ return of_reconfig_notifier_register(&platform_of_notifier);
+}
+EXPORT_SYMBOL_GPL(of_platform_register_reconfig_notifier);
+
+#endif
+
#endif /* CONFIG_OF_ADDRESS */
diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h
index c2b0627..01fe5d6 100644
--- a/include/linux/of_platform.h
+++ b/include/linux/of_platform.h
@@ -84,4 +84,14 @@ static inline int of_platform_populate(struct device_node *root,
static inline void of_platform_depopulate(struct device *parent) { }
#endif
+#ifdef CONFIG_OF_DYNAMIC
+extern int of_platform_register_reconfig_notifier(void);
+#else
+static inline int of_platform_register_reconfig_notifier(void)
+{
+ return 0;
+}
+#endif
+
+
#endif /* _LINUX_OF_PLATFORM_H */
--
1.7.12
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
