return 1;
 }
 
+#if defined(CONFIG_AVR32)
+
+static void toggle_bias(int is_on)
+{
+}
+
+#elif defined(CONFIG_ARCH_AT91)
+
+#include <asm/arch/at91_pmc.h>
+
+static void toggle_bias(int is_on)
+{
+       unsigned int uckr = at91_sys_read(AT91_CKGR_UCKR);
+
+       if (is_on)
+               at91_sys_write(AT91_CKGR_UCKR, uckr | AT91_PMC_BIASEN);
+       else
+               at91_sys_write(AT91_CKGR_UCKR, uckr & ~(AT91_PMC_BIASEN));
+}
+
+#endif /* CONFIG_ARCH_AT91 */
+
 static void next_fifo_transaction(struct usba_ep *ep, struct usba_request *req)
 {
        unsigned int transaction_len;
                DBG(DBG_HW, "Packet length: %u\n", pkt_len);
                if (pkt_len != sizeof(crq)) {
                        pr_warning("udc: Invalid packet length %u "
-                               "(expected %lu)\n", pkt_len, sizeof(crq));
+                               "(expected %zu)\n", pkt_len, sizeof(crq));
                        set_protocol_stall(udc, ep);
                        return;
                }
        DBG(DBG_INT, "irq, status=%#08x\n", status);
 
        if (status & USBA_DET_SUSPEND) {
+               toggle_bias(0);
                usba_writel(udc, INT_CLR, USBA_DET_SUSPEND);
                DBG(DBG_BUS, "Suspend detected\n");
                if (udc->gadget.speed != USB_SPEED_UNKNOWN
        }
 
        if (status & USBA_WAKE_UP) {
+               toggle_bias(1);
                usba_writel(udc, INT_CLR, USBA_WAKE_UP);
                DBG(DBG_BUS, "Wake Up CPU detected\n");
        }
        vbus = gpio_get_value(udc->vbus_pin);
        if (vbus != udc->vbus_prev) {
                if (vbus) {
-                       usba_writel(udc, CTRL, USBA_EN_USBA);
+                       toggle_bias(1);
+                       usba_writel(udc, CTRL, USBA_ENABLE_MASK);
                        usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
                } else {
                        udc->gadget.speed = USB_SPEED_UNKNOWN;
                        reset_all_endpoints(udc);
-                       usba_writel(udc, CTRL, 0);
+                       toggle_bias(0);
+                       usba_writel(udc, CTRL, USBA_DISABLE_MASK);
                        spin_unlock(&udc->lock);
                        udc->driver->disconnect(&udc->gadget);
                        spin_lock(&udc->lock);
        /* If Vbus is present, enable the controller and wait for reset */
        spin_lock_irqsave(&udc->lock, flags);
        if (vbus_is_present(udc) && udc->vbus_prev == 0) {
-               usba_writel(udc, CTRL, USBA_EN_USBA);
+               toggle_bias(1);
+               usba_writel(udc, CTRL, USBA_ENABLE_MASK);
                usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
        }
        spin_unlock_irqrestore(&udc->lock, flags);
        spin_unlock_irqrestore(&udc->lock, flags);
 
        /* This will also disable the DP pullup */
-       usba_writel(udc, CTRL, 0);
+       toggle_bias(0);
+       usba_writel(udc, CTRL, USBA_DISABLE_MASK);
 
        driver->unbind(&udc->gadget);
        udc->gadget.dev.driver = NULL;
 
        /* Make sure we start from a clean slate */
        clk_enable(pclk);
-       usba_writel(udc, CTRL, 0);
+       toggle_bias(0);
+       usba_writel(udc, CTRL, USBA_DISABLE_MASK);
        clk_disable(pclk);
 
        usba_ep = kmalloc(sizeof(struct usba_ep) * pdata->num_ep,