[net-next PATCH v3 09/15] device property: Introduce fwnode_get_id()

From: Calvin Johnson <calvin.johnson@oss.nxp.com>
To: Grant Likely <grant.likely@arm.com>,
	"Rafael J . Wysocki" <rafael@kernel.org>,
	Jeremy Linton <jeremy.linton@arm.com>,
	Andrew Lunn <andrew@lunn.ch>,
	Andy Shevchenko <andy.shevchenko@gmail.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Russell King - ARM Linux admin <linux@armlinux.org.uk>,
	Cristi Sovaiala <cristian.sovaiala@nxp.com>,
	Florin Laurentiu Chiculita <florinlaurentiu.chiculita@nxp.com>,
	Ioana Ciornei <ioana.ciornei@nxp.com>,
	Madalin Bucur <madalin.bucur@oss.nxp.com>,
	Heikki Krogerus <heikki.krogerus@linux.intel.com>,
	Marcin Wojtas <mw@semihalf.com>,
	Pieter Jansen Van Vuuren <pieter.jansenvv@bamboosystems.io>,
	Jon <jon@solid-run.com>
Cc: Diana Madalina Craciun <diana.craciun@nxp.com>,
	linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
	Laurentiu Tudor <laurentiu.tudor@nxp.com>,
	linux-acpi@vger.kernel.org, linux.cj@gmail.com,
	linux-arm-kernel@lists.infradead.org,
	Calvin Johnson <calvin.johnson@oss.nxp.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
	Randy Dunlap <rdunlap@infradead.org>,
	Saravana Kannan <saravanak@google.com>
Subject: [net-next PATCH v3 09/15] device property: Introduce fwnode_get_id()
Date: Tue, 12 Jan 2021 19:10:48 +0530	[thread overview]
Message-ID: <20210112134054.342-10-calvin.johnson@oss.nxp.com> (raw)
In-Reply-To: <20210112134054.342-1-calvin.johnson@oss.nxp.com>

Using fwnode_get_id(), get the reg property value for DT node
or get the _ADR object value for ACPI node.

Signed-off-by: Calvin Johnson <calvin.johnson@oss.nxp.com>
---

Changes in v3:
- Modified to retrieve reg property value for ACPI as well
- Resolved compilation issue with CONFIG_ACPI = n
- Added more info into documentation

Changes in v2: None

 drivers/base/property.c  | 33 +++++++++++++++++++++++++++++++++
 include/linux/property.h |  1 +
 2 files changed, 34 insertions(+)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 35b95c6ac0c6..2d51108cb936 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -580,6 +580,39 @@ const char *fwnode_get_name_prefix(const struct fwnode_handle *fwnode)
 	return fwnode_call_ptr_op(fwnode, get_name_prefix);
 }
 
+/**
+ * fwnode_get_id - Get the id of a fwnode.
+ * @fwnode: firmware node
+ * @id: id of the fwnode
+ *
+ * This function provides the id of a fwnode which can be either
+ * DT or ACPI node. For ACPI, "reg" property value, if present will
+ * be provided or else _ADR value will be provided.
+ * Returns 0 on success or a negative errno.
+ */
+int fwnode_get_id(struct fwnode_handle *fwnode, u32 *id)
+{
+#ifdef CONFIG_ACPI
+	unsigned long long adr;
+	acpi_status status;
+#endif
+	int ret;
+
+	ret = fwnode_property_read_u32(fwnode, "reg", id);
+	if (!(ret && is_acpi_node(fwnode)))
+		return ret;
+
+#ifdef CONFIG_ACPI
+	status = acpi_evaluate_integer(ACPI_HANDLE_FWNODE(fwnode),
+				       METHOD_NAME__ADR, NULL, &adr);
+	if (ACPI_FAILURE(status))
+		return -EINVAL;
+	*id = (u32)adr;
+#endif
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fwnode_get_id);
+
 /**
  * fwnode_get_parent - Return parent firwmare node
  * @fwnode: Firmware whose parent is retrieved
diff --git a/include/linux/property.h b/include/linux/property.h
index 0a9001fe7aea..3f41475f010b 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -82,6 +82,7 @@ struct fwnode_handle *fwnode_find_reference(const struct fwnode_handle *fwnode,
 
 const char *fwnode_get_name(const struct fwnode_handle *fwnode);
 const char *fwnode_get_name_prefix(const struct fwnode_handle *fwnode);
+int fwnode_get_id(struct fwnode_handle *fwnode, u32 *id);
 struct fwnode_handle *fwnode_get_parent(const struct fwnode_handle *fwnode);
 struct fwnode_handle *fwnode_get_next_parent(
 	struct fwnode_handle *fwnode);
-- 
2.17.1

