1 files changed, 193 insertions, 0 deletions
diff --git a/drivers/extcon/extcon-class.c b/drivers/extcon/extcon-class.c
index 76322330cbd..18d42c0e458 100644
--- a/drivers/extcon/extcon-class.c
+++ b/drivers/extcon/extcon-class.c
@@ -31,6 +31,7 @@
 #include <linux/extcon.h>
 #include <linux/slab.h>
 #include <linux/sysfs.h>
+#include <linux/of.h>
 
 /*
  * extcon_cable_name suggests the standard cable names for commonly used
@@ -564,6 +565,100 @@ static void dummy_sysfs_dev_release(struct device *dev)
 {
 }
 
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev)
+		return ERR_PTR(-ENOMEM);
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+
+	return edev;
+}
+
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
+ */
+void extcon_dev_free(struct extcon_dev *edev)
+{
+	kfree(edev);
+}
+EXPORT_SYMBOL_GPL(extcon_dev_free);
+
+static int devm_extcon_dev_match(struct device *dev, void *res, void *data)
+{
+	struct extcon_dev **r = res;
+
+	if (WARN_ON(!r || !*r))
+		return 0;
+
+	return *r == data;
+}
+
+static void devm_extcon_dev_release(struct device *dev, void *res)
+{
+	extcon_dev_free(*(struct extcon_dev **)res);
+}
+
+/**
+ * devm_extcon_dev_allocate - Allocate managed extcon device
+ * @dev:		device owning the extcon device being created
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function manages automatically the memory of extcon device using device
+ * resource management and simplify the control of freeing the memory of extcon
+ * device.
+ *
+ * Returns the pointer memory of allocated extcon_dev if success
+ * or ERR_PTR(err) if fail
+ */
+struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
+					    const char **supported_cable)
+{
+	struct extcon_dev **ptr, *edev;
+
+	ptr = devres_alloc(devm_extcon_dev_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	edev = extcon_dev_allocate(supported_cable);
+	if (IS_ERR(edev)) {
+		devres_free(ptr);
+		return edev;
+	}
+
+	*ptr = edev;
+	devres_add(dev, ptr);
+
+	return edev;
+}
+EXPORT_SYMBOL_GPL(devm_extcon_dev_allocate);
+
+void devm_extcon_dev_free(struct device *dev, struct extcon_dev *edev)
+{
+	WARN_ON(devres_release(dev, devm_extcon_dev_release,
+			       devm_extcon_dev_match, edev));
+}
+EXPORT_SYMBOL_GPL(devm_extcon_dev_free);
+
 /**
  * extcon_dev_register() - Register a new extcon device
  * @edev	: the new extcon device (should be allocated before calling)
@@ -818,6 +913,104 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 }
 EXPORT_SYMBOL_GPL(extcon_dev_unregister);
 
+static void devm_extcon_dev_unreg(struct device *dev, void *res)
+{
+	extcon_dev_unregister(*(struct extcon_dev **)res);
+}
+
+/**
+ * devm_extcon_dev_register() - Resource-managed extcon_dev_register()
+ * @dev:	device to allocate extcon device
+ * @edev:	the new extcon device to register
+ *
+ * Managed extcon_dev_register() function. If extcon device is attached with
+ * this function, that extcon device is automatically unregistered on driver
+ * detach. Internally this function calls extcon_dev_register() function.
+ * To get more information, refer that function.
+ *
+ * If extcon device is registered with this function and the device needs to be
+ * unregistered separately, devm_extcon_dev_unregister() should be used.
+ *
+ * Returns 0 if success or negaive error number if failure.
+ */
+int devm_extcon_dev_register(struct device *dev, struct extcon_dev *edev)
+{
+	struct extcon_dev **ptr;
+	int ret;
+
+	ptr = devres_alloc(devm_extcon_dev_unreg, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return -ENOMEM;
+
+	ret = extcon_dev_register(edev);
+	if (ret) {
+		devres_free(ptr);
+		return ret;
+	}
+
+	*ptr = edev;
+	devres_add(dev, ptr);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_extcon_dev_register);
+
+/**
+ * devm_extcon_dev_unregister() - Resource-managed extcon_dev_unregister()
+ * @dev:	device the extcon belongs to
+ * @edev:	the extcon device to unregister
+ *
+ * Unregister extcon device that is registered with devm_extcon_dev_register()
+ * function.
+ */
+void devm_extcon_dev_unregister(struct device *dev, struct extcon_dev *edev)
+{
+	WARN_ON(devres_release(dev, devm_extcon_dev_unreg,
+			       devm_extcon_dev_match, edev));
+}
+EXPORT_SYMBOL_GPL(devm_extcon_dev_unregister);
+
+#ifdef CONFIG_OF
+/*
+ * extcon_get_edev_by_phandle - Get the extcon device from devicetree
+ * @dev - instance to the given device
+ * @index - index into list of extcon_dev
+ *
+ * return the instance of extcon device
+ */
+struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
+{
+	struct device_node *node;
+	struct extcon_dev *edev;
+
+	if (!dev->of_node) {
+		dev_err(dev, "device does not have a device node entry\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	node = of_parse_phandle(dev->of_node, "extcon", index);
+	if (!node) {
+		dev_err(dev, "failed to get phandle in %s node\n",
+			dev->of_node->full_name);
+		return ERR_PTR(-ENODEV);
+	}
+
+	edev = extcon_get_extcon_dev(node->name);
+	if (!edev) {
+		dev_err(dev, "unable to get extcon device : %s\n", node->name);
+		return ERR_PTR(-ENODEV);
+	}
+
+	return edev;
+}
+#else
+struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
+{
+	return ERR_PTR(-ENOSYS);
+}
+#endif /* CONFIG_OF */
+EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
+
 static int __init extcon_class_init(void)
 {
 	return create_extcon_class();