Merge tag 'i2c-for-6.13-rc1-part3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c component probing support from Wolfram Sang:
 "Add OF component probing.

  Some devices are designed and manufactured with some components having
  multiple drop-in replacement options. These components are often
  connected to the mainboard via ribbon cables, having the same signals
  and pin assignments across all options. These may include the display
  panel and touchscreen on laptops and tablets, and the trackpad on
  laptops. Sometimes which component option is used in a particular
  device can be detected by some firmware provided identifier, other
  times that information is not available, and the kernel has to try to
  probe each device.

  Instead of a delicate dance between drivers and device tree quirks,
  this change introduces a simple I2C component probe function. For a
  given class of devices on the same I2C bus, it will go through all of
  them, doing a simple I2C read transfer and see which one of them
  responds. It will then enable the device that responds"

* tag 'i2c-for-6.13-rc1-part3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  MAINTAINERS: fix typo in I2C OF COMPONENT PROBER
  of: base: Document prefix argument for of_get_next_child_with_prefix()
  i2c: Fix whitespace style issue
  arm64: dts: mediatek: mt8173-elm-hana: Mark touchscreens and trackpads as fail
  platform/chrome: Introduce device tree hardware prober
  i2c: of-prober: Add GPIO support to simple helpers
  i2c: of-prober: Add simple helpers for regulator support
  i2c: Introduce OF component probe function
  of: base: Add for_each_child_of_node_with_prefix()
  of: dynamic: Add of_changeset_update_prop_string

2 files changed, 80 insertions, 0 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index a8b0c42bdc8e..7dc394255a0a 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -644,6 +644,42 @@ struct device_node *of_get_next_child(const struct device_node *node,
 }
 EXPORT_SYMBOL(of_get_next_child);
 
+/**
+ * of_get_next_child_with_prefix - Find the next child node with prefix
+ * @node:	parent node
+ * @prev:	previous child of the parent node, or NULL to get first
+ * @prefix:	prefix that the node name should have
+ *
+ * This function is like of_get_next_child(), except that it automatically
+ * skips any nodes whose name doesn't have the given prefix.
+ *
+ * Return: A node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_get_next_child_with_prefix(const struct device_node *node,
+						  struct device_node *prev,
+						  const char *prefix)
+{
+	struct device_node *next;
+	unsigned long flags;
+
+	if (!node)
+		return NULL;
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	next = prev ? prev->sibling : node->child;
+	for (; next; next = next->sibling) {
+		if (!of_node_name_prefix(next, prefix))
+			continue;
+		if (of_node_get(next))
+			break;
+	}
+	of_node_put(prev);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	return next;
+}
+EXPORT_SYMBOL(of_get_next_child_with_prefix);
+
 static struct device_node *of_get_next_status_child(const struct device_node *node,
 						    struct device_node *prev,
 						    bool (*checker)(const struct device_node *))
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index d45a8df61380..0aba760f7577 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);