3 files changed, 21 insertions, 1 deletions

diff --git a/arch/arm/mach-at91rm9200/devices.c b/arch/arm/mach-at91rm9200/devices.c
index 8df3e5245651..57eedd5beaf6 100644
--- a/arch/arm/mach-at91rm9200/devices.c
+++ b/arch/arm/mach-at91rm9200/devices.c
@@ -100,8 +100,10 @@ void __init at91_add_device_udc(struct at91_udc_data *data)
                 at91_set_gpio_input(data->vbus_pin, 0);
                 at91_set_deglitch(data->vbus_pin, 1);
         }
-        if (data->pullup_pin)
+        if (data->pullup_pin) {
                 at91_set_gpio_output(data->pullup_pin, 0);
+                at91_set_multi_drive(data->pullup_pin, 1);
+        }
 
         udc_data = *data;
         platform_device_register(&at91rm9200_udc_device);
diff --git a/arch/arm/mach-at91rm9200/gpio.c b/arch/arm/mach-at91rm9200/gpio.c
index 2fd2ef583e4d..a9f718bf8ba8 100644
--- a/arch/arm/mach-at91rm9200/gpio.c
+++ b/arch/arm/mach-at91rm9200/gpio.c
@@ -159,6 +159,23 @@ int __init_or_module at91_set_deglitch(unsigned pin, int is_on)
 }
 EXPORT_SYMBOL(at91_set_deglitch);
 
+/*
+ * enable/disable the multi-driver; This is only valid for output and
+ * allows the output pin to run as an open collector output.
+ */
+int __init_or_module at91_set_multi_drive(unsigned pin, int is_on)
+{
+        void __iomem    *pio = pin_to_controller(pin);
+        unsigned        mask = pin_to_mask(pin);
+
+        if (!pio)
+                return -EINVAL;
+
+        __raw_writel(mask, pio + (is_on ? PIO_MDER : PIO_MDDR));
+        return 0;
+}
+EXPORT_SYMBOL(at91_set_multi_drive);
+
 /*--------------------------------------------------------------------------*/
 
 
diff --git a/include/asm-arm/arch-at91rm9200/gpio.h b/include/asm-arm/arch-at91rm9200/gpio.h
index 0f0a61e2f129..6176ab2dc417 100644
--- a/include/asm-arm/arch-at91rm9200/gpio.h
+++ b/include/asm-arm/arch-at91rm9200/gpio.h
@@ -183,6 +183,7 @@ extern int at91_set_B_periph(unsigned pin, int use_pullup);
 extern int at91_set_gpio_input(unsigned pin, int use_pullup);
 extern int at91_set_gpio_output(unsigned pin, int value);
 extern int at91_set_deglitch(unsigned pin, int is_on);
+extern int at91_set_multi_drive(unsigned pin, int is_on);
 
 /* callable at any time */
 extern int at91_set_gpio_value(unsigned pin, int value);