[tip:irq/core] irqdomain: Check for NULL function pointer in irq_domain_free_irqs_hierarchy()

[tip-bot for David Daney <tipbot@zytor.com>]

Commit-ID:  0d12ec075a18f53e6f58ec95a4f534da2641bf9b
Gitweb:     http://git.kernel.org/tip/0d12ec075a18f53e6f58ec95a4f534da2641bf9b
Author:     David Daney <david.daney@cavium.com>
AuthorDate: Thu, 17 Aug 2017 17:53:33 -0700
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 18 Aug 2017 11:21:42 +0200

irqdomain: Check for NULL function pointer in irq_domain_free_irqs_hierarchy()

A follow-on patch will call irq_domain_free_irqs_hierarchy() when the
free() function pointer may be NULL.

Add a NULL pointer check to handle this new use case.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-gpio@vger.kernel.org
Link: http://lkml.kernel.org/r/1503017616-3252-5-git-send-email-david.daney@cavium.com

---
 kernel/irq/irqdomain.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 2093b88..24fda75 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1362,7 +1362,8 @@ static void irq_domain_free_irqs_hierarchy(struct irq_domain *domain,
 					   unsigned int irq_base,
 					   unsigned int nr_irqs)
 {
-	domain->ops->free(domain, irq_base, nr_irqs);
+	if (domain->ops->free)
+		domain->ops->free(domain, irq_base, nr_irqs);
 }
 
 int irq_domain_alloc_irqs_hierarchy(struct irq_domain *domain,