regmap: irq: Allow users to retrieve the irq_domain

This is useful for integration with other subsystems, especially MFD,
and provides an alternative API for users that request their own IRQs.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index e3bcc3f..b9e9979 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -19,6 +19,7 @@
 struct module;
 struct device;
 struct i2c_client;
+struct irq_domain;
 struct spi_device;
 struct regmap;
 struct regmap_range_cfg;
@@ -317,6 +318,7 @@
 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq);
+struct irq_domain *regmap_irq_get_domain(struct regmap_irq_chip_data *data);
 
 #else