[PATCH v5 01/10] of: dynamic: Add of_changeset_update_prop_string

Chen-Yu Tsai
2024-08-22T09:20:25Z

Add a helper function to add string property updates to an OF changeset.
This is similar to of_changeset_add_prop_string(), but instead of adding
the property (and failing if it exists), it will update the property.

This shall be used later in the DT hardware prober.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
---
Changes since v4:
- Use modern designated initializer for |prop|

Changes since v3:
- Use new __of_prop_free() helper
- Add new line before header declaration

Changes since v2:
- New patch added in v3
---
drivers/of/dynamic.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/of.h | 4 ++++
2 files changed, 48 insertions(+)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 110104a936d9..daa69d160a78 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -1072,3 +1072,47 @@ int of_changeset_add_prop_bool(struct of_changeset *ocs, struct device_node *np,
return of_changeset_add_prop_helper(ocs, np, &prop);
}
EXPORT_SYMBOL_GPL(of_changeset_add_prop_bool);
+
+static int of_changeset_update_prop_helper(struct of_changeset *ocs,
+ struct device_node *np,
+ const struct property *pp)
+{
+ struct property *new_pp;
+ int ret;
+
+ new_pp = __of_prop_dup(pp, GFP_KERNEL);
+ if (!new_pp)
+ return -ENOMEM;
+
+ ret = of_changeset_update_property(ocs, np, new_pp);
+ if (ret)
+ __of_prop_free(new_pp);
+
+ return ret;
+}
+
+/**
+ * of_changeset_update_prop_string - Add a string property update to a changeset
+ *
+ * @ocs: changeset pointer
+ * @np: device node pointer
+ * @prop_name: name of the property to be updated
+ * @str: pointer to null terminated string
+ *
+ * Create a string property to be updated and add it to a changeset.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_update_prop_string(struct of_changeset *ocs,
+ struct device_node *np,
+ const char *prop_name, const char *str)
+{
+ struct property prop = {
+ .name = (char *)prop_name,
+ .length = strlen(str) + 1,
+ .value = (void *)str,
+ };
+
+ return of_changeset_update_prop_helper(ocs, np, &prop);
+}
+EXPORT_SYMBOL_GPL(of_changeset_update_prop_string);
diff --git a/include/linux/of.h b/include/linux/of.h
index 85b60ac9eec5..046283be1cd3 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -1651,6 +1651,10 @@ static inline int of_changeset_add_prop_u32(struct of_changeset *ocs,
return of_changeset_add_prop_u32_array(ocs, np, prop_name, &val, 1);
}

+int of_changeset_update_prop_string(struct of_changeset *ocs,
+ struct device_node *np,
+ const char *prop_name, const char *str);
+
int of_changeset_add_prop_bool(struct of_changeset *ocs, struct device_node *np,
const char *prop_name);

--
2.46.0.184.g6999bdac58-goog