device property: Add fwnode_irq_get_byname

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>

diff --git a/drivers/base/property.c b/drivers/base/property.c
index e6497f6877ee8282d7519933b4801644359e8c86..fc59e0f7f9cc0e5ad2a0d70a1a745bc10a794fd5 100644 (file)
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -935,6 +935,35 @@ void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index)
 }
 EXPORT_SYMBOL(fwnode_iomap);
 
+/**
+ * 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_graph_get_next_endpoint - Get next endpoint firmware node
  * @fwnode: Pointer to the parent firmware node

diff --git a/include/linux/property.h b/include/linux/property.h
index 7399a0b45f9827ec43b10c5eb6e94039ed58baea..95d56a562b6a44cc12055a9f8fb5c3d9912ecbf1 100644 (file)
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -121,6 +121,7 @@ struct fwnode_handle *fwnode_handle_get(struct fwnode_handle *fwnode);
 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);
 
 void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index);