[PATCH 2/5] device property: add fwnode_device_is_reserved()

From: Zev Weiss <zev@bewilderbeest.net>
To: Frank Rowand <frowand.list@gmail.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org,
	Heikki Krogerus <heikki.krogerus@linux.intel.com>,
	Saravana Kannan <saravanak@google.com>,
	Zev Weiss <zev@bewilderbeest.net>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Andrew Jeffery <andrew@aj.id.au>,
	openbmc@lists.ozlabs.org, linux-kernel@vger.kernel.org,
	Daniel Scally <djrscally@gmail.com>,
	linux-acpi@vger.kernel.org, Jeremy Kerr <jk@codeconstruct.com.au>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Len Brown <lenb@kernel.org>
Subject: [PATCH 2/5] device property: add fwnode_device_is_reserved()
Date: Thu, 21 Oct 2021 19:00:29 -0700	[thread overview]
Message-ID: <20211022020032.26980-3-zev@bewilderbeest.net> (raw)
In-Reply-To: <20211022020032.26980-1-zev@bewilderbeest.net>

This is the fwnode API corresponding to of_device_is_reserved(), which
indicates that a device exists but may not be immediately accessible.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
---
 drivers/base/property.c  | 16 ++++++++++++++++
 include/linux/fwnode.h   |  2 ++
 include/linux/property.h |  1 +
 3 files changed, 19 insertions(+)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 453918eb7390..7b70cb04531c 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -845,6 +845,22 @@ bool fwnode_device_is_available(const struct fwnode_handle *fwnode)
 }
 EXPORT_SYMBOL_GPL(fwnode_device_is_available);
 
+/**
+ * fwnode_device_is_reserved - check if a device is reserved for use
+ * @fwnode: Pointer to the fwnode of the device.
+ *
+ * For fwnode node types that don't implement the .device_is_reserved()
+ * operation, this function returns false.
+ */
+bool fwnode_device_is_reserved(const struct fwnode_handle *fwnode)
+{
+	if (!fwnode_has_op(fwnode, device_is_reserved))
+		return false;
+
+	return fwnode_call_bool_op(fwnode, device_is_reserved);
+}
+EXPORT_SYMBOL_GPL(fwnode_device_is_reserved);
+
 /**
  * device_get_child_node_count - return the number of child nodes for device
  * @dev: Device to cound the child nodes for
diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h
index 9f4ad719bfe3..1a9aefbe12f1 100644
--- a/include/linux/fwnode.h
+++ b/include/linux/fwnode.h
@@ -86,6 +86,7 @@ struct fwnode_reference_args {
  * @get: Get a reference to an fwnode.
  * @put: Put a reference to an fwnode.
  * @device_is_available: Return true if the device is available.
+ * @device_is_reserved: Return true if the device is reserved.
  * @device_get_match_data: Return the device driver match data.
  * @property_present: Return true if a property is present.
  * @property_read_int_array: Read an array of integer properties. Return zero on
@@ -110,6 +111,7 @@ struct fwnode_operations {
 	struct fwnode_handle *(*get)(struct fwnode_handle *fwnode);
 	void (*put)(struct fwnode_handle *fwnode);
 	bool (*device_is_available)(const struct fwnode_handle *fwnode);
+	bool (*device_is_reserved)(const struct fwnode_handle *fwnode);
 	const void *(*device_get_match_data)(const struct fwnode_handle *fwnode,
 					     const struct device *dev);
 	bool (*property_present)(const struct fwnode_handle *fwnode,
diff --git a/include/linux/property.h b/include/linux/property.h
index 357513a977e5..455b022fa612 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -50,6 +50,7 @@ int device_property_match_string(struct device *dev,
 				 const char *propname, const char *string);
 
 bool fwnode_device_is_available(const struct fwnode_handle *fwnode);
+bool fwnode_device_is_reserved(const struct fwnode_handle *fwnode);
 bool fwnode_property_present(const struct fwnode_handle *fwnode,
 			     const char *propname);
 int fwnode_property_read_u8_array(const struct fwnode_handle *fwnode,
-- 
2.33.1

