2 files changed, 20 insertions, 0 deletions

diff --git a/arch/avr32/mach-at32ap/include/mach/portmux.h b/arch/avr32/mach-at32ap/include/mach/portmux.h
index b1abe6b4e4ef..4bbf99ec2c43 100644
--- a/arch/avr32/mach-at32ap/include/mach/portmux.h
+++ b/arch/avr32/mach-at32ap/include/mach/portmux.h
@@ -24,6 +24,7 @@
 void at32_select_periph(unsigned int pin, unsigned int periph,
                         unsigned long flags);
 void at32_select_gpio(unsigned int pin, unsigned long flags);
+void at32_deselect_pin(unsigned int pin);
 void at32_reserve_pin(unsigned int pin);
 
 #endif /* __ASM_ARCH_PORTMUX_H__ */
diff --git a/arch/avr32/mach-at32ap/pio.c b/arch/avr32/mach-at32ap/pio.c
index 405ee6bad4ce..90ef538ae547 100644
--- a/arch/avr32/mach-at32ap/pio.c
+++ b/arch/avr32/mach-at32ap/pio.c
@@ -134,6 +134,25 @@ fail:
         dump_stack();
 }
 
+/*
+ * Undo a previous pin reservation. Will not affect the hardware
+ * configuration.
+ */
+void at32_deselect_pin(unsigned int pin)
+{
+        struct pio_device *pio;
+        unsigned int pin_index = pin & 0x1f;
+
+        pio = gpio_to_pio(pin);
+        if (unlikely(!pio)) {
+                printk("pio: invalid pin %u\n", pin);
+                dump_stack();
+                return;
+        }
+
+        clear_bit(pin_index, &pio->pinmux_mask);
+}
+
 /* Reserve a pin, preventing anyone else from changing its configuration. */
 void __init at32_reserve_pin(unsigned int pin)
 {