From: Akhil R <akhilrajeev@nvidia.com>
Date: Fri, 28 Jan 2022 17:14:25 +0530
Subject: device property: Add fwnode_irq_get_byname
Git-commit: ca0acb511c21738b32386ce0f85c284b351d919e
Patch-mainline: v5.18-rc1
References: jsc#SLE-24569

Add fwnode_irq_get_byname() to get an interrupt by name from either
ACPI table or Device Tree, whichever is used for enumeration.

In the ACPI case, this allow us to use 'interrupt-names' in
_DSD which can be mapped to Interrupt() resource by index.
The implementation is similar to 'interrupt-names' in the
Device Tree.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Acked-by: Ivan T. Ivanov <iivanov@suse.de>
---
 drivers/base/property.c  |   29 +++++++++++++++++++++++++++++
 include/linux/property.h |    1 +
 2 files changed, 30 insertions(+)

--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -947,6 +947,35 @@ static void *fwnode_get_mac_addr(struct
 }
 
 /**
+ * fwnode_irq_get_byname - Get IRQ from a fwnode using its name
+ * @fwnode:	Pointer to the firmware node
+ * @name:	IRQ name
+ *
+ * Description:
+ * Find a match to the string @name in the 'interrupt-names' string array
+ * in _DSD for ACPI, or of_node for Device Tree. Then get the Linux IRQ
+ * number of the IRQ resource corresponding to the index of the matched
+ * string.
+ *
+ * Return:
+ * Linux IRQ number on success, or negative errno otherwise.
+ */
+int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name)
+{
+	int index;
+
+	if (!name)
+		return -EINVAL;
+
+	index = fwnode_property_match_string(fwnode, "interrupt-names",  name);
+	if (index < 0)
+		return index;
+
+	return fwnode_irq_get(fwnode, index);
+}
+EXPORT_SYMBOL(fwnode_irq_get_byname);
+
+/**
  * fwnode_get_mac_address - Get the MAC from the firmware node
  * @fwnode:	Pointer to the firmware node
  * @addr:	Address of buffer to store the MAC in
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -120,6 +120,7 @@ struct fwnode_handle *fwnode_handle_get(
 void fwnode_handle_put(struct fwnode_handle *fwnode);
 
 int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index);
+int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name);
 
 unsigned int device_get_child_node_count(struct device *dev);