irq/generic-chip: Provide devm_irq_alloc_generic_chip()

Provide a resource managed variant of irq_alloc_generic_chip().
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-doc@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Link: http://lkml.kernel.org/r/1496246820-13250-5-git-send-email-brgl@bgdev.pl

Documentation/driver-model/devres.txt

@@ -311,6 +311,7 @@ IRQ
   devm_irq_alloc_desc_at()
   devm_irq_alloc_desc_from()
   devm_irq_alloc_descs_from()
+  devm_irq_alloc_generic_chip()
 
 LED
   devm_led_classdev_register()

include/linux/irq.h

@@ -958,6 +958,11 @@ int irq_setup_alt_chip(struct irq_data *d, unsigned int type);
 void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk,
 			     unsigned int clr, unsigned int set);
 
+struct irq_chip_generic *
+devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
+			    unsigned int irq_base, void __iomem *reg_base,
+			    irq_flow_handler_t handler);
+
 struct irq_chip_generic *irq_get_domain_generic_chip(struct irq_domain *d, unsigned int hw_irq);
 
 int __irq_alloc_domain_generic_chips(struct irq_domain *d, int irqs_per_chip,

kernel/irq/devres.c

@@ -4,6 +4,8 @@
 #include <linux/gfp.h>
 #include <linux/irq.h>
 
+#include "internals.h"
+
 /*
  * Device resource management aware IRQ request/free implementation.
  */
@@ -198,3 +200,35 @@ int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
 	return base;
 }
 EXPORT_SYMBOL_GPL(__devm_irq_alloc_descs);
+
+#ifdef CONFIG_GENERIC_IRQ_CHIP
+/**
+ * devm_irq_alloc_generic_chip - Allocate and initialize a generic chip
+ *                               for a managed device
+ * @dev:	Device to allocate the generic chip for
+ * @name:	Name of the irq chip
+ * @num_ct:	Number of irq_chip_type instances associated with this
+ * @irq_base:	Interrupt base nr for this chip
+ * @reg_base:	Register base address (virtual)
+ * @handler:	Default flow handler associated with this chip
+ *
+ * Returns an initialized irq_chip_generic structure. The chip defaults
+ * to the primary (index 0) irq_chip_type and @handler
+ */
+struct irq_chip_generic *
+devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
+			    unsigned int irq_base, void __iomem *reg_base,
+			    irq_flow_handler_t handler)
+{
+	struct irq_chip_generic *gc;
+	unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
+
+	gc = devm_kzalloc(dev, sz, GFP_KERNEL);
+	if (gc)
+		irq_init_generic_chip(gc, name, num_ct,
+				      irq_base, reg_base, handler);
+
+	return gc;
+}
+EXPORT_SYMBOL_GPL(devm_irq_alloc_generic_chip);
+#endif /* CONFIG_GENERIC_IRQ_CHIP */