drivers/usb/gadget/pxa27x_udc.c - u-boot-mtk - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * PXA27x USB device driver for u-boot.
  *
  * Copyright (C) 2007 Rodolfo Giometti <giometti@linux.it>
  * Copyright (C) 2007 Eurotech S.p.A.  <info@eurotech.it>
  * Copyright (C) 2008 Vivek Kutal      <vivek.kutal@azingo.com>
  */


 #include <common.h>
 #include <asm/arch/hardware.h>
 #include <asm/byteorder.h>
 #include <asm/io.h>
 #include <usbdevice.h>
 #include <usb/pxa27x_udc.h>
 #include <usb/udc.h>

 #include "ep0.h"

 /* number of endpoints on this UDC */
 #define UDC_MAX_ENDPOINTS	24

 static struct urb *ep0_urb;
 static struct usb_device_instance *udc_device;
 static int ep0state = EP0_IDLE;

 #ifdef USBDDBG
 static void udc_dump_buffer(char *name, u8 *buf, int len)
 {
 	usbdbg("%s - buf %p, len %d", name, buf, len);
 	print_buffer(0, buf, 1, len, 0);
 }
 #else
 #define udc_dump_buffer(name, buf, len)		/* void */
 #endif

 static inline void udc_ack_int_UDCCR(int mask)
 {
 	writel(readl(USIR1) | mask, USIR1);
 }

 /*
  * If the endpoint has an active tx_urb, then the next packet of data from the
  * URB is written to the tx FIFO.
  * The total amount of data in the urb is given by urb->actual_length.
  * The maximum amount of data that can be sent in any one packet is given by
  * endpoint->tx_packetSize.
  * The number of data bytes from this URB that have already been transmitted
  * is given by endpoint->sent.
  * endpoint->last is updated by this routine with the number of data bytes
  * transmitted in this packet.
  */
 static int udc_write_urb(struct usb_endpoint_instance *endpoint)
 {
 	struct urb *urb = endpoint->tx_urb;
 	int ep_num = endpoint->endpoint_address & USB_ENDPOINT_NUMBER_MASK;
 	u32 *data32 = (u32 *) urb->buffer;
 	u8  *data8 = (u8 *) urb->buffer;
 	unsigned int i, n, w, b, is_short;
 	int timeout = 2000;	/* 2ms */

 	if (!urb || !urb->actual_length)
 		return -1;

 	n = min_t(unsigned int, urb->actual_length - endpoint->sent,
 		  endpoint->tx_packetSize);
 	if (n <= 0)
 		return -1;

 	usbdbg("write urb on ep %d", ep_num);
 #if defined(USBDDBG) && defined(USBDPARANOIA)
 	usbdbg("urb: buf %p, buf_len %d, actual_len %d",
 		urb->buffer, urb->buffer_length, urb->actual_length);
 	usbdbg("endpoint: sent %d, tx_packetSize %d, last %d",
 		endpoint->sent, endpoint->tx_packetSize, endpoint->last);
 #endif

 	is_short = n != endpoint->tx_packetSize;
 	w = n / 4;
 	b = n % 4;
 	usbdbg("n %d%s w %d b %d", n, is_short ? "-s" : "", w, b);
 	udc_dump_buffer("urb write", data8 + endpoint->sent, n);

 	/* Prepare for data send */
 	if (ep_num)
 		writel(UDCCSR_PC ,UDCCSN(ep_num));

 	for (i = 0; i < w; i++)
 		  writel(data32[endpoint->sent / 4 + i], UDCDN(ep_num));

 	for (i = 0; i < b; i++)
 		  writeb(data8[endpoint->sent + w * 4 + i], UDCDN(ep_num));

 	/* Set "Packet Complete" if less data then tx_packetSize */
 	if (is_short)
 		writel(ep_num ? UDCCSR_SP : UDCCSR0_IPR, UDCCSN(ep_num));

 	/* Wait for data sent */
 	if (ep_num) {
 		while (!(readl(UDCCSN(ep_num)) & UDCCSR_PC)) {
 			if (timeout-- == 0)
 				return -1;
 			else
 				udelay(1);
 		}
 	}

 	endpoint->last = n;

 	if (ep_num) {
 		usbd_tx_complete(endpoint);
 	} else {
 		endpoint->sent += n;
 		endpoint->last -= n;
 	}

 	if (endpoint->sent >= urb->actual_length) {
 		urb->actual_length = 0;
 		endpoint->sent = 0;
 		endpoint->last = 0;
 	}

 	if ((endpoint->sent >= urb->actual_length) && (!ep_num)) {
 		usbdbg("ep0 IN stage done");
 		if (is_short)
 			ep0state = EP0_IDLE;
 		else
 			ep0state = EP0_XFER_COMPLETE;
 	}

 	return 0;
 }

 static int udc_read_urb(struct usb_endpoint_instance *endpoint)
 {
 	struct urb *urb = endpoint->rcv_urb;
 	int ep_num = endpoint->endpoint_address & USB_ENDPOINT_NUMBER_MASK;
 	u32 *data32 = (u32 *) urb->buffer;
 	unsigned int i, n;

 	usbdbg("read urb on ep %d", ep_num);
 #if defined(USBDDBG) && defined(USBDPARANOIA)
 	usbdbg("urb: buf %p, buf_len %d, actual_len %d",
 		urb->buffer, urb->buffer_length, urb->actual_length);
 	usbdbg("endpoint: rcv_packetSize %d",
 		endpoint->rcv_packetSize);
 #endif

 	if (readl(UDCCSN(ep_num)) & UDCCSR_BNE)
 		n = readl(UDCBCN(ep_num)) & 0x3ff;
 	else /* zlp */
 		n = 0;

 	usbdbg("n %d%s", n, n != endpoint->rcv_packetSize ? "-s" : "");
 	for (i = 0; i < n; i += 4)
 		data32[urb->actual_length / 4 + i / 4] = readl(UDCDN(ep_num));

 	udc_dump_buffer("urb read", (u8 *) data32, urb->actual_length + n);
 	usbd_rcv_complete(endpoint, n, 0);

 	return 0;
 }

 static int udc_read_urb_ep0(void)
 {
 	u32 *data32 = (u32 *) ep0_urb->buffer;
 	u8 *data8 = (u8 *) ep0_urb->buffer;
 	unsigned int i, n, w, b;

 	usbdbg("read urb on ep 0");
 #if defined(USBDDBG) && defined(USBDPARANOIA)
 	usbdbg("urb: buf %p, buf_len %d, actual_len %d",
 		ep0_urb->buffer, ep0_urb->buffer_length, ep0_urb->actual_length);
 #endif

 	n = readl(UDCBCR0);
 	w = n / 4;
 	b = n % 4;

 	for (i = 0; i < w; i++) {
 		data32[ep0_urb->actual_length / 4 + i] = readl(UDCDN(0));
 		/* ep0_urb->actual_length += 4; */
 	}

 	for (i = 0; i < b; i++) {
 		data8[ep0_urb->actual_length + w * 4 + i] = readb(UDCDN(0));
 		/* ep0_urb->actual_length++; */
 	}

 	ep0_urb->actual_length += n;

 	udc_dump_buffer("urb read", (u8 *) data32, ep0_urb->actual_length);

 	writel(UDCCSR0_OPC | UDCCSR0_IPR, UDCCSR0);
 	if (ep0_urb->actual_length == ep0_urb->device_request.wLength)
 		return 1;

 	return 0;
 }

 static void udc_handle_ep0(struct usb_endpoint_instance *endpoint)
 {
 	u32 udccsr0 = readl(UDCCSR0);
 	u32 *data = (u32 *) &ep0_urb->device_request;
 	int i;

 	usbdbg("udccsr0 %x", udccsr0);

 	/* Clear stall status */
 	if (udccsr0 & UDCCSR0_SST) {
 		usberr("clear stall status");
 		writel(UDCCSR0_SST, UDCCSR0);
 		ep0state = EP0_IDLE;
 	}

 	/* previous request unfinished?  non-error iff back-to-back ... */
 	if ((udccsr0 & UDCCSR0_SA) != 0 && ep0state != EP0_IDLE)
 		ep0state = EP0_IDLE;

 	switch (ep0state) {

 	case EP0_IDLE:
 		udccsr0 = readl(UDCCSR0);
 		/* Start control request? */
 		if ((udccsr0 & (UDCCSR0_OPC | UDCCSR0_SA | UDCCSR0_RNE))
 			== (UDCCSR0_OPC | UDCCSR0_SA | UDCCSR0_RNE)) {

 			/* Read SETUP packet.
 			 * SETUP packet size is 8 bytes (aka 2 words)
 			 */
 			usbdbg("try reading SETUP packet");
 			for (i = 0; i < 2; i++) {
 				if ((readl(UDCCSR0) & UDCCSR0_RNE) == 0) {
 					usberr("setup packet too short:%d", i);
 					goto stall;
 				}
 				data[i] = readl(UDCDR0);
 			}

 			writel(readl(UDCCSR0) | UDCCSR0_OPC | UDCCSR0_SA, UDCCSR0);
 			if ((readl(UDCCSR0) & UDCCSR0_RNE) != 0) {
 				usberr("setup packet too long");
 				goto stall;
 			}

 			udc_dump_buffer("ep0 setup read", (u8 *) data, 8);

 			if (ep0_urb->device_request.wLength == 0) {
 				usbdbg("Zero Data control Packet\n");
 				if (ep0_recv_setup(ep0_urb)) {
 					usberr("Invalid Setup Packet\n");
 					udc_dump_buffer("ep0 setup read",
 								(u8 *)data, 8);
 					goto stall;
 				}
 				writel(UDCCSR0_IPR, UDCCSR0);
 				ep0state = EP0_IDLE;
 			} else {
 				/* Check direction */
 				if ((ep0_urb->device_request.bmRequestType &
 						USB_REQ_DIRECTION_MASK)
 						== USB_REQ_HOST2DEVICE) {
 					ep0state = EP0_OUT_DATA;
 					ep0_urb->buffer =
 						(u8 *)ep0_urb->buffer_data;
 					ep0_urb->buffer_length =
 						sizeof(ep0_urb->buffer_data);
 					ep0_urb->actual_length = 0;
 					writel(UDCCSR0_IPR, UDCCSR0);
 				} else {
 					/* The ep0_recv_setup function has
 					 * already placed our response packet
 					 * data in ep0_urb->buffer and the
 					 * packet length in
 					 * ep0_urb->actual_length.
 					 */
 					if (ep0_recv_setup(ep0_urb)) {
 stall:
 						usberr("Invalid setup packet");
 						udc_dump_buffer("ep0 setup read"
 							, (u8 *) data, 8);
 						ep0state = EP0_IDLE;

 						writel(UDCCSR0_SA |
 						UDCCSR0_OPC | UDCCSR0_FST |
 						UDCCS0_FTF, UDCCSR0);

 						return;
 					}

 					endpoint->tx_urb = ep0_urb;
 					endpoint->sent = 0;
 					usbdbg("EP0_IN_DATA");
 					ep0state = EP0_IN_DATA;
 					if (udc_write_urb(endpoint) < 0)
 						goto stall;

 				}
 			}
 			return;
 		} else if ((udccsr0 & (UDCCSR0_OPC | UDCCSR0_SA))
 			== (UDCCSR0_OPC|UDCCSR0_SA)) {
 			usberr("Setup Active but no data. Stalling ....\n");
 			goto stall;
 		} else {
 			usbdbg("random early IRQs");
 			/* Some random early IRQs:
 			 * - we acked FST
 			 * - IPR cleared
 			 * - OPC got set, without SA (likely status stage)
 			 */
 			writel(udccsr0 & (UDCCSR0_SA | UDCCSR0_OPC), UDCCSR0);
 		}
 		break;

 	case EP0_OUT_DATA:

 		if ((udccsr0 & UDCCSR0_OPC) && !(udccsr0 & UDCCSR0_SA)) {
 			if (udc_read_urb_ep0()) {
 read_complete:
 				ep0state = EP0_IDLE;
 				if (ep0_recv_setup(ep0_urb)) {
 					/* Not a setup packet, stall next
 					 * EP0 transaction
 					 */
 					udc_dump_buffer("ep0 setup read",
 							(u8 *) data, 8);
 					usberr("can't parse setup packet\n");
 					goto stall;
 				}
 			}
 		} else if (!(udccsr0 & UDCCSR0_OPC) &&
 				!(udccsr0 & UDCCSR0_IPR)) {
 			if (ep0_urb->device_request.wLength ==
 				ep0_urb->actual_length)
 				goto read_complete;

 			usberr("Premature Status\n");
 			ep0state = EP0_IDLE;
 		}
 		break;

 	case EP0_IN_DATA:
 		/* GET_DESCRIPTOR etc */
 		if (udccsr0 & UDCCSR0_OPC) {
 			writel(UDCCSR0_OPC | UDCCSR0_FTF, UDCCSR0);
 			usberr("ep0in premature status");
 			ep0state = EP0_IDLE;
 		} else {
 			/* irq was IPR clearing */
 			if (udc_write_urb(endpoint) < 0) {
 				usberr("ep0_write_error\n");
 				goto stall;
 			}
 		}
 		break;

 	case EP0_XFER_COMPLETE:
 		writel(UDCCSR0_IPR, UDCCSR0);
 		ep0state = EP0_IDLE;
 		break;

 	default:
 		usbdbg("Default\n");
 	}
 	writel(USIR0_IR0, USIR0);
 }

 static void udc_handle_ep(struct usb_endpoint_instance *endpoint)
 {
 	int ep_addr = endpoint->endpoint_address;
 	int ep_num = ep_addr & USB_ENDPOINT_NUMBER_MASK;
 	int ep_isout = (ep_addr & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT;

 	u32 flags = readl(UDCCSN(ep_num)) & (UDCCSR_SST | UDCCSR_TRN);
 	if (flags)
 		writel(flags, UDCCSN(ep_num));

 	if (ep_isout)
 		udc_read_urb(endpoint);
 	else
 		udc_write_urb(endpoint);

 	writel(UDCCSR_PC, UDCCSN(ep_num));
 }

 static void udc_state_changed(void)
 {

 	writel(readl(UDCCR) | UDCCR_SMAC, UDCCR);

 	usbdbg("New UDC settings are: conf %d - inter %d - alter %d",
 	       (readl(UDCCR) & UDCCR_ACN) >> UDCCR_ACN_S,
 	       (readl(UDCCR) & UDCCR_AIN) >> UDCCR_AIN_S,
 	       (readl(UDCCR) & UDCCR_AAISN) >> UDCCR_AAISN_S);

 	usbd_device_event_irq(udc_device, DEVICE_CONFIGURED, 0);
 	writel(UDCISR1_IRCC, UDCISR1);
 }

 void udc_irq(void)
 {
 	int handled;
 	struct usb_endpoint_instance *endpoint;
 	int ep_num, i;
 	u32 udcisr0;

 	do {
 		handled = 0;
 		/* Suspend Interrupt Request */
 		if (readl(USIR1) & UDCCR_SUSIR) {
 			usbdbg("Suspend\n");
 			udc_ack_int_UDCCR(UDCCR_SUSIR);
 			handled = 1;
 			ep0state = EP0_IDLE;
 		}

 		/* Resume Interrupt Request */
 		if (readl(USIR1) & UDCCR_RESIR) {
 			udc_ack_int_UDCCR(UDCCR_RESIR);
 			handled = 1;
 			usbdbg("USB resume\n");
 		}

 		if (readl(USIR1) & (1<<31)) {
 			handled = 1;
 			udc_state_changed();
 		}

 		/* Reset Interrupt Request */
 		if (readl(USIR1) & UDCCR_RSTIR) {
 			udc_ack_int_UDCCR(UDCCR_RSTIR);
 			handled = 1;
 			usbdbg("Reset\n");
 			usbd_device_event_irq(udc_device, DEVICE_RESET, 0);
 		} else {
 			if (readl(USIR0))
 				usbdbg("UISR0: %x \n", readl(USIR0));

 			if (readl(USIR0) & 0x2)
 				writel(0x2, USIR0);

 			/* Control traffic */
 			if (readl(USIR0)  & USIR0_IR0) {
 				handled = 1;
 				writel(USIR0_IR0, USIR0);
 				udc_handle_ep0(udc_device->bus->endpoint_array);
 			}

 			endpoint = udc_device->bus->endpoint_array;
 			for (i = 0; i < udc_device->bus->max_endpoints; i++) {
 				ep_num = (endpoint[i].endpoint_address) &
 						USB_ENDPOINT_NUMBER_MASK;
 				if (!ep_num)
 					continue;
 				udcisr0 = readl(UDCISR0);
 				if (udcisr0 &
 					UDCISR_INT(ep_num, UDC_INT_PACKETCMP)) {
 					writel(UDCISR_INT(ep_num, UDC_INT_PACKETCMP),
 					       UDCISR0);
 					udc_handle_ep(&endpoint[i]);
 				}
 			}
 		}

 	} while (handled);
 }

 /* The UDCCR reg contains mask and interrupt status bits,
  * so using '|=' isn't safe as it may ack an interrupt.
  */
 #define UDCCR_OEN		(1 << 31)   /* On-the-Go Enable */
 #define UDCCR_MASK_BITS     	(UDCCR_OEN | UDCCR_UDE)

 static inline void udc_set_mask_UDCCR(int mask)
 {
     writel((readl(UDCCR) & UDCCR_MASK_BITS) | (mask & UDCCR_MASK_BITS), UDCCR);
 }

 static inline void udc_clear_mask_UDCCR(int mask)
 {
     writel((readl(UDCCR) & UDCCR_MASK_BITS) & ~(mask & UDCCR_MASK_BITS), UDCCR);
 }

 static void pio_irq_enable(int ep_num)
 {
 	if (ep_num < 16)
 		writel(readl(UDCICR0) | 3 << (ep_num * 2), UDCICR0);
 	else {
 		ep_num -= 16;
 		writel(readl(UDCICR1) | 3 << (ep_num * 2), UDCICR1);
 	}
 }

 /*
  * udc_set_nak
  *
  * Allow upper layers to signal lower layers should not accept more RX data
  */
 void udc_set_nak(int ep_num)
 {
 	/* TODO */
 }

 /*
  * udc_unset_nak
  *
  * Suspend sending of NAK tokens for DATA OUT tokens on a given endpoint.
  * Switch off NAKing on this endpoint to accept more data output from host.
  */
 void udc_unset_nak(int ep_num)
 {
 	/* TODO */
 }

 int udc_endpoint_write(struct usb_endpoint_instance *endpoint)
 {
 	return udc_write_urb(endpoint);
 }

 /* Associate a physical endpoint with endpoint instance */
 void udc_setup_ep(struct usb_device_instance *device, unsigned int id,
 				struct usb_endpoint_instance *endpoint)
 {
 	int ep_num, ep_addr, ep_isout, ep_type, ep_size;
 	int config, interface, alternate;
 	u32 tmp;

 	usbdbg("setting up endpoint id %d", id);

 	if (!endpoint) {
 		usberr("endpoint void!");
 		return;
 	}

 	ep_num = endpoint->endpoint_address & USB_ENDPOINT_NUMBER_MASK;
 	if (ep_num >= UDC_MAX_ENDPOINTS) {
 		usberr("unable to setup ep %d!", ep_num);
 		return;
 	}

 	pio_irq_enable(ep_num);
 	if (ep_num == 0) {
 		/* Done for ep0 */
 		return;
 	}

 	config = 1;
 	interface = 0;
 	alternate = 0;

 	usbdbg("config %d - interface %d - alternate %d",
 		config, interface, alternate);

 	ep_addr = endpoint->endpoint_address;
 	ep_num = ep_addr & USB_ENDPOINT_NUMBER_MASK;
 	ep_isout = (ep_addr & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT;
 	ep_type = ep_isout ? endpoint->rcv_attributes : endpoint->tx_attributes;
 	ep_size = ep_isout ? endpoint->rcv_packetSize : endpoint->tx_packetSize;

 	usbdbg("addr %x, num %d, dir %s, type %s, packet size %d",
 		ep_addr, ep_num,
 		ep_isout ? "out" : "in",
 		ep_type == USB_ENDPOINT_XFER_ISOC ? "isoc" :
 		ep_type == USB_ENDPOINT_XFER_BULK ? "bulk" :
 		ep_type == USB_ENDPOINT_XFER_INT ? "int" : "???",
 		ep_size
 		);

 	/* Configure UDCCRx */
 	tmp = 0;
 	tmp |= (config << UDCCONR_CN_S) & UDCCONR_CN;
 	tmp |= (interface << UDCCONR_IN_S) & UDCCONR_IN;
 	tmp |= (alternate << UDCCONR_AISN_S) & UDCCONR_AISN;
 	tmp |= (ep_num << UDCCONR_EN_S) & UDCCONR_EN;
 	tmp |= (ep_type << UDCCONR_ET_S) & UDCCONR_ET;
 	tmp |= ep_isout ? 0 : UDCCONR_ED;
 	tmp |= (ep_size << UDCCONR_MPS_S) & UDCCONR_MPS;
 	tmp |= UDCCONR_EE;

 	writel(tmp, UDCCN(ep_num));

 	usbdbg("UDCCR%c = %x", 'A' + ep_num-1, readl(UDCCN(ep_num)));
 	usbdbg("UDCCSR%c = %x", 'A' + ep_num-1, readl(UDCCSN(ep_num)));
 }

 /* Connect the USB device to the bus */
 void udc_connect(void)
 {
 	usbdbg("UDC connect");

 #ifdef CONFIG_USB_DEV_PULLUP_GPIO
 	/* Turn on the USB connection by enabling the pullup resistor */
 	writel(readl(GPDR(CONFIG_USB_DEV_PULLUP_GPIO))
 		     | GPIO_bit(CONFIG_USB_DEV_PULLUP_GPIO),
 	       GPDR(CONFIG_USB_DEV_PULLUP_GPIO));
 	writel(GPIO_bit(CONFIG_USB_DEV_PULLUP_GPIO), GPSR(CONFIG_USB_DEV_PULLUP_GPIO));
 #else
 	/* Host port 2 transceiver D+ pull up enable */
 	writel(readl(UP2OCR) | UP2OCR_DPPUE, UP2OCR);
 #endif
 }

 /* Disconnect the USB device to the bus */
 void udc_disconnect(void)
 {
 	usbdbg("UDC disconnect");

 #ifdef CONFIG_USB_DEV_PULLUP_GPIO
 	/* Turn off the USB connection by disabling the pullup resistor */
 	writel(GPIO_bit(CONFIG_USB_DEV_PULLUP_GPIO), GPCR(CONFIG_USB_DEV_PULLUP_GPIO));
 #else
 	/* Host port 2 transceiver D+ pull up disable */
 	writel(readl(UP2OCR) & ~UP2OCR_DPPUE, UP2OCR);
 #endif
 }

 /* Switch on the UDC */
 void udc_enable(struct usb_device_instance *device)
 {

 	ep0state = EP0_IDLE;

 	/* enable endpoint 0, A, B's Packet Complete Interrupt. */
 	writel(0xffffffff, UDCICR0);
 	writel(0xa8000000, UDCICR1);

 	/* clear the interrupt status/control registers */
 	writel(0xffffffff, UDCISR0);
 	writel(0xffffffff, UDCISR1);

 	/* set UDC-enable */
 	udc_set_mask_UDCCR(UDCCR_UDE);

 	udc_device = device;
 	if (!ep0_urb)
 		ep0_urb = usbd_alloc_urb(udc_device,
 				udc_device->bus->endpoint_array);
 	else
 		usbinfo("ep0_urb %p already allocated", ep0_urb);

 	usbdbg("UDC Enabled\n");
 }

 /* Need to check this again */
 void udc_disable(void)
 {
 	usbdbg("disable UDC");

 	udc_clear_mask_UDCCR(UDCCR_UDE);

 	/* Disable clock for USB device */
 	writel(readl(CKEN) & ~CKEN11_USB, CKEN);

 	/* Free ep0 URB */
 	if (ep0_urb) {
 		usbd_dealloc_urb(ep0_urb);
 		ep0_urb = NULL;
 	}

 	/* Reset device pointer */
 	udc_device = NULL;
 }

 /* Allow udc code to do any additional startup */
 void udc_startup_events(struct usb_device_instance *device)
 {
 	/* The DEVICE_INIT event puts the USB device in the state STATE_INIT */
 	usbd_device_event_irq(device, DEVICE_INIT, 0);

 	/* The DEVICE_CREATE event puts the USB device in the state
 	 * STATE_ATTACHED */
 	usbd_device_event_irq(device, DEVICE_CREATE, 0);

 	/* Some USB controller driver implementations signal
 	 * DEVICE_HUB_CONFIGURED and DEVICE_RESET events here.
 	 * DEVICE_HUB_CONFIGURED causes a transition to the state
 	 * STATE_POWERED, and DEVICE_RESET causes a transition to
 	 * the state STATE_DEFAULT.
 	 */
 	udc_enable(device);
 }

 /* Initialize h/w stuff */
 int udc_init(void)
 {
 	udc_device = NULL;
 	usbdbg("PXA27x usbd start");

 	/* Enable clock for USB device */
 	writel(readl(CKEN) | CKEN11_USB, CKEN);

 	/* Disable the UDC */
 	udc_clear_mask_UDCCR(UDCCR_UDE);

 	/* Disable IRQs: we don't use them */
 	writel(0, UDCICR0);
 	writel(0, UDCICR1);

 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* PXA27x USB device driver for u-boot.
	*
	* Copyright (C) 2007 Rodolfo Giometti <giometti@linux.it>
	* Copyright (C) 2007 Eurotech S.p.A. <info@eurotech.it>
	* Copyright (C) 2008 Vivek Kutal <vivek.kutal@azingo.com>
	*/


	#include <common.h>
	#include <asm/arch/hardware.h>
	#include <asm/byteorder.h>
	#include <asm/io.h>
	#include <usbdevice.h>
	#include <usb/pxa27x_udc.h>
	#include <usb/udc.h>

	#include "ep0.h"

	/* number of endpoints on this UDC */
	#define UDC_MAX_ENDPOINTS 24

	static struct urb *ep0_urb;
	static struct usb_device_instance *udc_device;
	static int ep0state = EP0_IDLE;

	#ifdef USBDDBG
	static void udc_dump_buffer(char name, u8 buf, int len)
	{
	usbdbg("%s - buf %p, len %d", name, buf, len);
	print_buffer(0, buf, 1, len, 0);
	}
	#else
	#define udc_dump_buffer(name, buf, len) /* void */
	#endif

	static inline void udc_ack_int_UDCCR(int mask)
	{
	writel(readl(USIR1) \| mask, USIR1);
	}

	/*
	* If the endpoint has an active tx_urb, then the next packet of data from the
	* URB is written to the tx FIFO.
	* The total amount of data in the urb is given by urb->actual_length.
	* The maximum amount of data that can be sent in any one packet is given by
	* endpoint->tx_packetSize.
	* The number of data bytes from this URB that have already been transmitted
	* is given by endpoint->sent.
	* endpoint->last is updated by this routine with the number of data bytes
	* transmitted in this packet.
	*/
	static int udc_write_urb(struct usb_endpoint_instance *endpoint)
	{
	struct urb *urb = endpoint->tx_urb;
	int ep_num = endpoint->endpoint_address & USB_ENDPOINT_NUMBER_MASK;
	u32 data32 = (u32 ) urb->buffer;
	u8 data8 = (u8 ) urb->buffer;
	unsigned int i, n, w, b, is_short;
	int timeout = 2000; /* 2ms */

	if (!urb \|\| !urb->actual_length)
	return -1;

	n = min_t(unsigned int, urb->actual_length - endpoint->sent,
	endpoint->tx_packetSize);
	if (n <= 0)
	return -1;

	usbdbg("write urb on ep %d", ep_num);
	#if defined(USBDDBG) && defined(USBDPARANOIA)
	usbdbg("urb: buf %p, buf_len %d, actual_len %d",
	urb->buffer, urb->buffer_length, urb->actual_length);
	usbdbg("endpoint: sent %d, tx_packetSize %d, last %d",
	endpoint->sent, endpoint->tx_packetSize, endpoint->last);
	#endif

	is_short = n != endpoint->tx_packetSize;
	w = n / 4;
	b = n % 4;
	usbdbg("n %d%s w %d b %d", n, is_short ? "-s" : "", w, b);
	udc_dump_buffer("urb write", data8 + endpoint->sent, n);

	/* Prepare for data send */
	if (ep_num)
	writel(UDCCSR_PC ,UDCCSN(ep_num));

	for (i = 0; i < w; i++)
	writel(data32[endpoint->sent / 4 + i], UDCDN(ep_num));

	for (i = 0; i < b; i++)
	writeb(data8[endpoint->sent + w * 4 + i], UDCDN(ep_num));

	/* Set "Packet Complete" if less data then tx_packetSize */
	if (is_short)
	writel(ep_num ? UDCCSR_SP : UDCCSR0_IPR, UDCCSN(ep_num));

	/* Wait for data sent */
	if (ep_num) {
	while (!(readl(UDCCSN(ep_num)) & UDCCSR_PC)) {
	if (timeout-- == 0)
	return -1;
	else
	udelay(1);
	}
	}

	endpoint->last = n;

	if (ep_num) {
	usbd_tx_complete(endpoint);
	} else {
	endpoint->sent += n;
	endpoint->last -= n;
	}

	if (endpoint->sent >= urb->actual_length) {
	urb->actual_length = 0;
	endpoint->sent = 0;
	endpoint->last = 0;
	}

	if ((endpoint->sent >= urb->actual_length) && (!ep_num)) {
	usbdbg("ep0 IN stage done");
	if (is_short)
	ep0state = EP0_IDLE;
	else
	ep0state = EP0_XFER_COMPLETE;
	}

	return 0;
	}

	static int udc_read_urb(struct usb_endpoint_instance *endpoint)
	{
	struct urb *urb = endpoint->rcv_urb;
	int ep_num = endpoint->endpoint_address & USB_ENDPOINT_NUMBER_MASK;
	u32 data32 = (u32 ) urb->buffer;
	unsigned int i, n;

	usbdbg("read urb on ep %d", ep_num);
	#if defined(USBDDBG) && defined(USBDPARANOIA)
	usbdbg("urb: buf %p, buf_len %d, actual_len %d",
	urb->buffer, urb->buffer_length, urb->actual_length);
	usbdbg("endpoint: rcv_packetSize %d",
	endpoint->rcv_packetSize);
	#endif

	if (readl(UDCCSN(ep_num)) & UDCCSR_BNE)
	n = readl(UDCBCN(ep_num)) & 0x3ff;
	else /* zlp */
	n = 0;

	usbdbg("n %d%s", n, n != endpoint->rcv_packetSize ? "-s" : "");
	for (i = 0; i < n; i += 4)
	data32[urb->actual_length / 4 + i / 4] = readl(UDCDN(ep_num));

	udc_dump_buffer("urb read", (u8 *) data32, urb->actual_length + n);
	usbd_rcv_complete(endpoint, n, 0);

	return 0;
	}

	static int udc_read_urb_ep0(void)
	{
	u32 data32 = (u32 ) ep0_urb->buffer;
	u8 data8 = (u8 ) ep0_urb->buffer;
	unsigned int i, n, w, b;

	usbdbg("read urb on ep 0");
	#if defined(USBDDBG) && defined(USBDPARANOIA)
	usbdbg("urb: buf %p, buf_len %d, actual_len %d",
	ep0_urb->buffer, ep0_urb->buffer_length, ep0_urb->actual_length);
	#endif

	n = readl(UDCBCR0);
	w = n / 4;
	b = n % 4;

	for (i = 0; i < w; i++) {
	data32[ep0_urb->actual_length / 4 + i] = readl(UDCDN(0));
	/* ep0_urb->actual_length += 4; */
	}

	for (i = 0; i < b; i++) {
	data8[ep0_urb->actual_length + w * 4 + i] = readb(UDCDN(0));
	/* ep0_urb->actual_length++; */
	}

	ep0_urb->actual_length += n;

	udc_dump_buffer("urb read", (u8 *) data32, ep0_urb->actual_length);

	writel(UDCCSR0_OPC \| UDCCSR0_IPR, UDCCSR0);
	if (ep0_urb->actual_length == ep0_urb->device_request.wLength)
	return 1;

	return 0;
	}

	static void udc_handle_ep0(struct usb_endpoint_instance *endpoint)
	{
	u32 udccsr0 = readl(UDCCSR0);
	u32 data = (u32 ) &ep0_urb->device_request;
	int i;

	usbdbg("udccsr0 %x", udccsr0);

	/* Clear stall status */
	if (udccsr0 & UDCCSR0_SST) {
	usberr("clear stall status");
	writel(UDCCSR0_SST, UDCCSR0);
	ep0state = EP0_IDLE;
	}

	/* previous request unfinished? non-error iff back-to-back ... */
	if ((udccsr0 & UDCCSR0_SA) != 0 && ep0state != EP0_IDLE)
	ep0state = EP0_IDLE;

	switch (ep0state) {

	case EP0_IDLE:
	udccsr0 = readl(UDCCSR0);
	/* Start control request? */
	if ((udccsr0 & (UDCCSR0_OPC \| UDCCSR0_SA \| UDCCSR0_RNE))
	== (UDCCSR0_OPC \| UDCCSR0_SA \| UDCCSR0_RNE)) {

	/* Read SETUP packet.
	* SETUP packet size is 8 bytes (aka 2 words)
	*/
	usbdbg("try reading SETUP packet");
	for (i = 0; i < 2; i++) {
	if ((readl(UDCCSR0) & UDCCSR0_RNE) == 0) {
	usberr("setup packet too short:%d", i);
	goto stall;
	}
	data[i] = readl(UDCDR0);
	}

	writel(readl(UDCCSR0) \| UDCCSR0_OPC \| UDCCSR0_SA, UDCCSR0);
	if ((readl(UDCCSR0) & UDCCSR0_RNE) != 0) {
	usberr("setup packet too long");
	goto stall;
	}

	udc_dump_buffer("ep0 setup read", (u8 *) data, 8);

	if (ep0_urb->device_request.wLength == 0) {
	usbdbg("Zero Data control Packet\n");
	if (ep0_recv_setup(ep0_urb)) {
	usberr("Invalid Setup Packet\n");
	udc_dump_buffer("ep0 setup read",
	(u8 *)data, 8);
	goto stall;
	}
	writel(UDCCSR0_IPR, UDCCSR0);
	ep0state = EP0_IDLE;
	} else {
	/* Check direction */
	if ((ep0_urb->device_request.bmRequestType &
	USB_REQ_DIRECTION_MASK)
	== USB_REQ_HOST2DEVICE) {
	ep0state = EP0_OUT_DATA;
	ep0_urb->buffer =
	(u8 *)ep0_urb->buffer_data;
	ep0_urb->buffer_length =
	sizeof(ep0_urb->buffer_data);
	ep0_urb->actual_length = 0;
	writel(UDCCSR0_IPR, UDCCSR0);
	} else {
	/* The ep0_recv_setup function has
	* already placed our response packet
	* data in ep0_urb->buffer and the
	* packet length in
	* ep0_urb->actual_length.
	*/
	if (ep0_recv_setup(ep0_urb)) {
	stall:
	usberr("Invalid setup packet");
	udc_dump_buffer("ep0 setup read"
	, (u8 *) data, 8);
	ep0state = EP0_IDLE;

	writel(UDCCSR0_SA \|
	UDCCSR0_OPC \| UDCCSR0_FST \|
	UDCCS0_FTF, UDCCSR0);

	return;
	}

	endpoint->tx_urb = ep0_urb;
	endpoint->sent = 0;
	usbdbg("EP0_IN_DATA");
	ep0state = EP0_IN_DATA;
	if (udc_write_urb(endpoint) < 0)
	goto stall;

	}
	}
	return;
	} else if ((udccsr0 & (UDCCSR0_OPC \| UDCCSR0_SA))
	== (UDCCSR0_OPC\|UDCCSR0_SA)) {
	usberr("Setup Active but no data. Stalling ....\n");
	goto stall;
	} else {
	usbdbg("random early IRQs");
	/* Some random early IRQs:
	* - we acked FST
	* - IPR cleared
	* - OPC got set, without SA (likely status stage)
	*/
	writel(udccsr0 & (UDCCSR0_SA \| UDCCSR0_OPC), UDCCSR0);
	}
	break;

	case EP0_OUT_DATA:

	if ((udccsr0 & UDCCSR0_OPC) && !(udccsr0 & UDCCSR0_SA)) {
	if (udc_read_urb_ep0()) {
	read_complete:
	ep0state = EP0_IDLE;
	if (ep0_recv_setup(ep0_urb)) {
	/* Not a setup packet, stall next
	* EP0 transaction
	*/
	udc_dump_buffer("ep0 setup read",
	(u8 *) data, 8);
	usberr("can't parse setup packet\n");
	goto stall;
	}
	}
	} else if (!(udccsr0 & UDCCSR0_OPC) &&
	!(udccsr0 & UDCCSR0_IPR)) {
	if (ep0_urb->device_request.wLength ==
	ep0_urb->actual_length)
	goto read_complete;

	usberr("Premature Status\n");
	ep0state = EP0_IDLE;
	}
	break;

	case EP0_IN_DATA:
	/* GET_DESCRIPTOR etc */
	if (udccsr0 & UDCCSR0_OPC) {
	writel(UDCCSR0_OPC \| UDCCSR0_FTF, UDCCSR0);
	usberr("ep0in premature status");
	ep0state = EP0_IDLE;
	} else {
	/* irq was IPR clearing */
	if (udc_write_urb(endpoint) < 0) {
	usberr("ep0_write_error\n");
	goto stall;
	}
	}
	break;

	case EP0_XFER_COMPLETE:
	writel(UDCCSR0_IPR, UDCCSR0);
	ep0state = EP0_IDLE;
	break;

	default:
	usbdbg("Default\n");
	}
	writel(USIR0_IR0, USIR0);
	}

	static void udc_handle_ep(struct usb_endpoint_instance *endpoint)
	{
	int ep_addr = endpoint->endpoint_address;
	int ep_num = ep_addr & USB_ENDPOINT_NUMBER_MASK;
	int ep_isout = (ep_addr & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT;

	u32 flags = readl(UDCCSN(ep_num)) & (UDCCSR_SST \| UDCCSR_TRN);
	if (flags)
	writel(flags, UDCCSN(ep_num));

	if (ep_isout)
	udc_read_urb(endpoint);
	else
	udc_write_urb(endpoint);

	writel(UDCCSR_PC, UDCCSN(ep_num));
	}

	static void udc_state_changed(void)
	{

	writel(readl(UDCCR) \| UDCCR_SMAC, UDCCR);

	usbdbg("New UDC settings are: conf %d - inter %d - alter %d",
	(readl(UDCCR) & UDCCR_ACN) >> UDCCR_ACN_S,
	(readl(UDCCR) & UDCCR_AIN) >> UDCCR_AIN_S,
	(readl(UDCCR) & UDCCR_AAISN) >> UDCCR_AAISN_S);

	usbd_device_event_irq(udc_device, DEVICE_CONFIGURED, 0);
	writel(UDCISR1_IRCC, UDCISR1);
	}

	void udc_irq(void)
	{
	int handled;
	struct usb_endpoint_instance *endpoint;
	int ep_num, i;
	u32 udcisr0;

	do {
	handled = 0;
	/* Suspend Interrupt Request */
	if (readl(USIR1) & UDCCR_SUSIR) {
	usbdbg("Suspend\n");
	udc_ack_int_UDCCR(UDCCR_SUSIR);
	handled = 1;
	ep0state = EP0_IDLE;
	}

	/* Resume Interrupt Request */
	if (readl(USIR1) & UDCCR_RESIR) {
	udc_ack_int_UDCCR(UDCCR_RESIR);
	handled = 1;
	usbdbg("USB resume\n");
	}

	if (readl(USIR1) & (1<<31)) {
	handled = 1;
	udc_state_changed();
	}

	/* Reset Interrupt Request */
	if (readl(USIR1) & UDCCR_RSTIR) {
	udc_ack_int_UDCCR(UDCCR_RSTIR);
	handled = 1;
	usbdbg("Reset\n");
	usbd_device_event_irq(udc_device, DEVICE_RESET, 0);
	} else {
	if (readl(USIR0))
	usbdbg("UISR0: %x \n", readl(USIR0));

	if (readl(USIR0) & 0x2)
	writel(0x2, USIR0);

	/* Control traffic */
	if (readl(USIR0) & USIR0_IR0) {
	handled = 1;
	writel(USIR0_IR0, USIR0);
	udc_handle_ep0(udc_device->bus->endpoint_array);
	}

	endpoint = udc_device->bus->endpoint_array;
	for (i = 0; i < udc_device->bus->max_endpoints; i++) {
	ep_num = (endpoint[i].endpoint_address) &
	USB_ENDPOINT_NUMBER_MASK;
	if (!ep_num)
	continue;
	udcisr0 = readl(UDCISR0);
	if (udcisr0 &
	UDCISR_INT(ep_num, UDC_INT_PACKETCMP)) {
	writel(UDCISR_INT(ep_num, UDC_INT_PACKETCMP),
	UDCISR0);
	udc_handle_ep(&endpoint[i]);
	}
	}
	}

	} while (handled);
	}

	/* The UDCCR reg contains mask and interrupt status bits,
	* so using '\|=' isn't safe as it may ack an interrupt.
	*/
	#define UDCCR_OEN (1 << 31) /* On-the-Go Enable */
	#define UDCCR_MASK_BITS (UDCCR_OEN \| UDCCR_UDE)

	static inline void udc_set_mask_UDCCR(int mask)
	{
	writel((readl(UDCCR) & UDCCR_MASK_BITS) \| (mask & UDCCR_MASK_BITS), UDCCR);
	}

	static inline void udc_clear_mask_UDCCR(int mask)
	{
	writel((readl(UDCCR) & UDCCR_MASK_BITS) & ~(mask & UDCCR_MASK_BITS), UDCCR);
	}

	static void pio_irq_enable(int ep_num)
	{
	if (ep_num < 16)
	writel(readl(UDCICR0) \| 3 << (ep_num * 2), UDCICR0);
	else {
	ep_num -= 16;
	writel(readl(UDCICR1) \| 3 << (ep_num * 2), UDCICR1);
	}
	}

	/*
	* udc_set_nak
	*
	* Allow upper layers to signal lower layers should not accept more RX data
	*/
	void udc_set_nak(int ep_num)
	{
	/* TODO */
	}

	/*
	* udc_unset_nak
	*
	* Suspend sending of NAK tokens for DATA OUT tokens on a given endpoint.
	* Switch off NAKing on this endpoint to accept more data output from host.
	*/
	void udc_unset_nak(int ep_num)
	{
	/* TODO */
	}

	int udc_endpoint_write(struct usb_endpoint_instance *endpoint)
	{
	return udc_write_urb(endpoint);
	}

	/* Associate a physical endpoint with endpoint instance */
	void udc_setup_ep(struct usb_device_instance *device, unsigned int id,
	struct usb_endpoint_instance *endpoint)
	{
	int ep_num, ep_addr, ep_isout, ep_type, ep_size;
	int config, interface, alternate;
	u32 tmp;

	usbdbg("setting up endpoint id %d", id);

	if (!endpoint) {
	usberr("endpoint void!");
	return;
	}

	ep_num = endpoint->endpoint_address & USB_ENDPOINT_NUMBER_MASK;
	if (ep_num >= UDC_MAX_ENDPOINTS) {
	usberr("unable to setup ep %d!", ep_num);
	return;
	}

	pio_irq_enable(ep_num);
	if (ep_num == 0) {
	/* Done for ep0 */
	return;
	}

	config = 1;
	interface = 0;
	alternate = 0;

	usbdbg("config %d - interface %d - alternate %d",
	config, interface, alternate);

	ep_addr = endpoint->endpoint_address;
	ep_num = ep_addr & USB_ENDPOINT_NUMBER_MASK;
	ep_isout = (ep_addr & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT;
	ep_type = ep_isout ? endpoint->rcv_attributes : endpoint->tx_attributes;
	ep_size = ep_isout ? endpoint->rcv_packetSize : endpoint->tx_packetSize;

	usbdbg("addr %x, num %d, dir %s, type %s, packet size %d",
	ep_addr, ep_num,
	ep_isout ? "out" : "in",
	ep_type == USB_ENDPOINT_XFER_ISOC ? "isoc" :
	ep_type == USB_ENDPOINT_XFER_BULK ? "bulk" :
	ep_type == USB_ENDPOINT_XFER_INT ? "int" : "???",
	ep_size
	);

	/* Configure UDCCRx */
	tmp = 0;
	tmp \|= (config << UDCCONR_CN_S) & UDCCONR_CN;
	tmp \|= (interface << UDCCONR_IN_S) & UDCCONR_IN;
	tmp \|= (alternate << UDCCONR_AISN_S) & UDCCONR_AISN;
	tmp \|= (ep_num << UDCCONR_EN_S) & UDCCONR_EN;
	tmp \|= (ep_type << UDCCONR_ET_S) & UDCCONR_ET;
	tmp \|= ep_isout ? 0 : UDCCONR_ED;
	tmp \|= (ep_size << UDCCONR_MPS_S) & UDCCONR_MPS;
	tmp \|= UDCCONR_EE;

	writel(tmp, UDCCN(ep_num));

	usbdbg("UDCCR%c = %x", 'A' + ep_num-1, readl(UDCCN(ep_num)));
	usbdbg("UDCCSR%c = %x", 'A' + ep_num-1, readl(UDCCSN(ep_num)));
	}

	/* Connect the USB device to the bus */
	void udc_connect(void)
	{
	usbdbg("UDC connect");

	#ifdef CONFIG_USB_DEV_PULLUP_GPIO
	/* Turn on the USB connection by enabling the pullup resistor */
	writel(readl(GPDR(CONFIG_USB_DEV_PULLUP_GPIO))
	\| GPIO_bit(CONFIG_USB_DEV_PULLUP_GPIO),
	GPDR(CONFIG_USB_DEV_PULLUP_GPIO));
	writel(GPIO_bit(CONFIG_USB_DEV_PULLUP_GPIO), GPSR(CONFIG_USB_DEV_PULLUP_GPIO));
	#else
	/* Host port 2 transceiver D+ pull up enable */
	writel(readl(UP2OCR) \| UP2OCR_DPPUE, UP2OCR);
	#endif
	}

	/* Disconnect the USB device to the bus */
	void udc_disconnect(void)
	{
	usbdbg("UDC disconnect");

	#ifdef CONFIG_USB_DEV_PULLUP_GPIO
	/* Turn off the USB connection by disabling the pullup resistor */
	writel(GPIO_bit(CONFIG_USB_DEV_PULLUP_GPIO), GPCR(CONFIG_USB_DEV_PULLUP_GPIO));
	#else
	/* Host port 2 transceiver D+ pull up disable */
	writel(readl(UP2OCR) & ~UP2OCR_DPPUE, UP2OCR);
	#endif
	}

	/* Switch on the UDC */
	void udc_enable(struct usb_device_instance *device)
	{

	ep0state = EP0_IDLE;

	/* enable endpoint 0, A, B's Packet Complete Interrupt. */
	writel(0xffffffff, UDCICR0);
	writel(0xa8000000, UDCICR1);

	/* clear the interrupt status/control registers */
	writel(0xffffffff, UDCISR0);
	writel(0xffffffff, UDCISR1);

	/* set UDC-enable */
	udc_set_mask_UDCCR(UDCCR_UDE);

	udc_device = device;
	if (!ep0_urb)
	ep0_urb = usbd_alloc_urb(udc_device,
	udc_device->bus->endpoint_array);
	else
	usbinfo("ep0_urb %p already allocated", ep0_urb);

	usbdbg("UDC Enabled\n");
	}

	/* Need to check this again */
	void udc_disable(void)
	{
	usbdbg("disable UDC");

	udc_clear_mask_UDCCR(UDCCR_UDE);

	/* Disable clock for USB device */
	writel(readl(CKEN) & ~CKEN11_USB, CKEN);

	/* Free ep0 URB */
	if (ep0_urb) {
	usbd_dealloc_urb(ep0_urb);
	ep0_urb = NULL;
	}

	/* Reset device pointer */
	udc_device = NULL;
	}

	/* Allow udc code to do any additional startup */
	void udc_startup_events(struct usb_device_instance *device)
	{
	/* The DEVICE_INIT event puts the USB device in the state STATE_INIT */
	usbd_device_event_irq(device, DEVICE_INIT, 0);

	/* The DEVICE_CREATE event puts the USB device in the state
	* STATE_ATTACHED */
	usbd_device_event_irq(device, DEVICE_CREATE, 0);

	/* Some USB controller driver implementations signal
	* DEVICE_HUB_CONFIGURED and DEVICE_RESET events here.
	* DEVICE_HUB_CONFIGURED causes a transition to the state
	* STATE_POWERED, and DEVICE_RESET causes a transition to
	* the state STATE_DEFAULT.
	*/
	udc_enable(device);
	}

	/* Initialize h/w stuff */
	int udc_init(void)
	{
	udc_device = NULL;
	usbdbg("PXA27x usbd start");

	/* Enable clock for USB device */
	writel(readl(CKEN) \| CKEN11_USB, CKEN);

	/* Disable the UDC */
	udc_clear_mask_UDCCR(UDCCR_UDE);

	/* Disable IRQs: we don't use them */
	writel(0, UDCICR0);
	writel(0, UDCICR1);

	return 0;
	}