of: Transactional DT support.

Introducing DT transactional support.

A DT transaction is a method which allows one to apply changes
in the live tree, in such a way that either the full set of changes
take effect, or the state of the tree can be rolled-back to the
state it was before it was attempted. An applied transaction
can be rolled-back at any time.

Documentation is in
	Documentation/devicetree/changesets.txt

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[glikely: Removed device notifiers and reworked to be more consistent]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
This commit is contained in:
Pantelis Antoniou
2014-07-04 19:58:49 +03:00
committed by Grant Likely
parent 259092a35c
commit 201c910bd6
6 changed files with 530 additions and 0 deletions

View File

@@ -786,4 +786,80 @@ typedef void (*of_init_fn_1)(struct device_node *);
#define OF_DECLARE_2(table, name, compat, fn) \
_OF_DECLARE(table, name, compat, fn, of_init_fn_2)
/**
* struct of_changeset_entry - Holds a changeset entry
*
* @node: list_head for the log list
* @action: notifier action
* @np: pointer to the device node affected
* @prop: pointer to the property affected
* @old_prop: hold a pointer to the original property
*
* Every modification of the device tree during a changeset
* is held in a list of of_changeset_entry structures.
* That way we can recover from a partial application, or we can
* revert the changeset
*/
struct of_changeset_entry {
struct list_head node;
unsigned long action;
struct device_node *np;
struct property *prop;
struct property *old_prop;
};
/**
* struct of_changeset - changeset tracker structure
*
* @entries: list_head for the changeset entries
*
* changesets are a convenient way to apply bulk changes to the
* live tree. In case of an error, changes are rolled-back.
* changesets live on after initial application, and if not
* destroyed after use, they can be reverted in one single call.
*/
struct of_changeset {
struct list_head entries;
};
#ifdef CONFIG_OF_DYNAMIC
extern void of_changeset_init(struct of_changeset *ocs);
extern void of_changeset_destroy(struct of_changeset *ocs);
extern int of_changeset_apply(struct of_changeset *ocs);
extern int of_changeset_revert(struct of_changeset *ocs);
extern int of_changeset_action(struct of_changeset *ocs,
unsigned long action, struct device_node *np,
struct property *prop);
static inline int of_changeset_attach_node(struct of_changeset *ocs,
struct device_node *np)
{
return of_changeset_action(ocs, OF_RECONFIG_ATTACH_NODE, np, NULL);
}
static inline int of_changeset_detach_node(struct of_changeset *ocs,
struct device_node *np)
{
return of_changeset_action(ocs, OF_RECONFIG_DETACH_NODE, np, NULL);
}
static inline int of_changeset_add_property(struct of_changeset *ocs,
struct device_node *np, struct property *prop)
{
return of_changeset_action(ocs, OF_RECONFIG_ADD_PROPERTY, np, prop);
}
static inline int of_changeset_remove_property(struct of_changeset *ocs,
struct device_node *np, struct property *prop)
{
return of_changeset_action(ocs, OF_RECONFIG_REMOVE_PROPERTY, np, prop);
}
static inline int of_changeset_update_property(struct of_changeset *ocs,
struct device_node *np, struct property *prop)
{
return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop);
}
#endif
#endif /* _LINUX_OF_H */