usb : musb : Adding host controller driver for Mentor USB controller

Adding Mentor USB core functionality and Mentor USB Host controller
functionality for Mentor USB OTG controller (musbhdrc).

Signed-off-by: Ravi Babu <ravibabu@ti.com>
Signed-off-by: Swaminathan S <swami.iyer@ti.com>
Signed-off-by: Thomas Abraham <t-abraham@ti.com>
Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>
Signed-off-by: Remy Bohmer <linux@bohmer.net>

1 files changed, 792 insertions, 0 deletions

diff --git a/drivers/usb/musb_hcd.c b/drivers/usb/musb_hcd.c
new file mode 100644
index 0000000..352a0d4
--- /dev/null
+++ b/drivers/usb/musb_hcd.c
@@ -0,0 +1,792 @@
+/*
+ * Mentor USB OTG Core host controller driver.
+ *
+ * Copyright (c) 2008 Texas Instruments
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * Author: Thomas Abraham t-abraham@ti.com, Texas Instruments
+ */
+
+#include <common.h>
+#include "musb_hcd.h"
+
+/* MSC control transfers */
+#define USB_MSC_BBB_RESET 	0xFF
+#define USB_MSC_BBB_GET_MAX_LUN	0xFE
+
+/* Endpoint configuration information */
+static struct musb_epinfo epinfo[3] = {
+	{MUSB_BULK_EP, 1, 512}, /* EP1 - Bluk Out - 512 Bytes */
+	{MUSB_BULK_EP, 0, 512}, /* EP1 - Bluk In  - 512 Bytes */
+	{MUSB_INTR_EP, 0, 64}   /* EP2 - Interrupt IN - 64 Bytes */
+};
+
+/*
+ * This function writes the data toggle value.
+ */
+static void write_toggle(struct usb_device *dev, u8 ep, u8 dir_out)
+{
+	u16 toggle = usb_gettoggle(dev, ep, dir_out);
+	u16 csr;
+
+	if (dir_out) {
+		if (!toggle)
+			writew(MUSB_TXCSR_CLRDATATOG, &musbr->txcsr);
+		else {
+			csr = readw(&musbr->txcsr);
+			csr |= MUSB_TXCSR_H_WR_DATATOGGLE;
+			writew(csr, &musbr->txcsr);
+			csr |= (toggle << MUSB_TXCSR_H_DATATOGGLE_SHIFT);
+			writew(csr, &musbr->txcsr);
+		}
+	} else {
+		if (!toggle)
+			writew(MUSB_RXCSR_CLRDATATOG, &musbr->rxcsr);
+		else {
+			csr = readw(&musbr->rxcsr);
+			csr |= MUSB_RXCSR_H_WR_DATATOGGLE;
+			writew(csr, &musbr->rxcsr);
+			csr |= (toggle << MUSB_S_RXCSR_H_DATATOGGLE);
+			writew(csr, &musbr->rxcsr);
+		}
+	}
+}
+
+/*
+ * This function checks if RxStall has occured on the endpoint. If a RxStall
+ * has occured, the RxStall is cleared and 1 is returned. If RxStall has
+ * not occured, 0 is returned.
+ */
+static u8 check_stall(u8 ep, u8 dir_out)
+{
+	u16 csr;
+
+	/* For endpoint 0 */
+	if (!ep) {
+		csr = readw(&musbr->txcsr);
+		if (csr & MUSB_CSR0_H_RXSTALL) {
+			csr &= ~MUSB_CSR0_H_RXSTALL;
+			writew(csr, &musbr->txcsr);
+			return 1;
+		}
+	} else { /* For non-ep0 */
+		if (dir_out) { /* is it tx ep */
+			csr = readw(&musbr->txcsr);
+			if (csr & MUSB_TXCSR_H_RXSTALL) {
+				csr &= ~MUSB_TXCSR_H_RXSTALL;
+				writew(csr, &musbr->txcsr);
+				return 1;
+			}
+		} else { /* is it rx ep */
+			csr = readw(&musbr->rxcsr);
+			if (csr & MUSB_RXCSR_H_RXSTALL) {
+				csr &= ~MUSB_RXCSR_H_RXSTALL;
+				writew(csr, &musbr->rxcsr);
+				return 1;
+			}
+		}
+	}
+	return 0;
+}
+
+/*
+ * waits until ep0 is ready. Returns 0 if ep is ready, -1 for timeout
+ * error and -2 for stall.
+ */
+static int wait_until_ep0_ready(struct usb_device *dev, u32 bit_mask)
+{
+	u16 csr;
+	int result = 1;
+
+	while (result > 0) {
+		csr = readw(&musbr->txcsr);
+		if (csr & MUSB_CSR0_H_ERROR) {
+			csr &= ~MUSB_CSR0_H_ERROR;
+			writew(csr, &musbr->txcsr);
+			dev->status = USB_ST_CRC_ERR;
+			result = -1;
+			break;
+		}
+
+		switch (bit_mask) {
+		case MUSB_CSR0_TXPKTRDY:
+			if (!(csr & MUSB_CSR0_TXPKTRDY)) {
+				if (check_stall(MUSB_CONTROL_EP, 0)) {
+					dev->status = USB_ST_STALLED;
+					result = -2;
+				} else
+					result = 0;
+			}
+			break;
+
+		case MUSB_CSR0_RXPKTRDY:
+			if (check_stall(MUSB_CONTROL_EP, 0)) {
+				dev->status = USB_ST_STALLED;
+				result = -2;
+			} else
+				if (csr & MUSB_CSR0_RXPKTRDY)
+					result = 0;
+			break;
+
+		case MUSB_CSR0_H_REQPKT:
+			if (!(csr & MUSB_CSR0_H_REQPKT)) {
+				if (check_stall(MUSB_CONTROL_EP, 0)) {
+					dev->status = USB_ST_STALLED;
+					result = -2;
+				} else
+					result = 0;
+			}
+			break;
+		}
+	}
+	return result;
+}
+
+/*
+ * waits until tx ep is ready. Returns 1 when ep is ready and 0 on error.
+ */
+static u8 wait_until_txep_ready(struct usb_device *dev, u8 ep)
+{
+	u16 csr;
+
+	do {
+		if (check_stall(ep, 1)) {
+			dev->status = USB_ST_STALLED;
+			return 0;
+		}
+
+		csr = readw(&musbr->txcsr);
+		if (csr & MUSB_TXCSR_H_ERROR) {
+			dev->status = USB_ST_CRC_ERR;
+			return 0;
+		}
+	} while (csr & MUSB_TXCSR_TXPKTRDY);
+	return 1;
+}
+
+/*
+ * waits until rx ep is ready. Returns 1 when ep is ready and 0 on error.
+ */
+static u8 wait_until_rxep_ready(struct usb_device *dev, u8 ep)
+{
+	u16 csr;
+
+	do {
+		if (check_stall(ep, 0)) {
+			dev->status = USB_ST_STALLED;
+			return 0;
+		}
+
+		csr = readw(&musbr->rxcsr);
+		if (csr & MUSB_RXCSR_H_ERROR) {
+			dev->status = USB_ST_CRC_ERR;
+			return 0;
+		}
+	} while (!(csr & MUSB_RXCSR_RXPKTRDY));
+	return 1;
+}
+
+/*
+ * This function performs the setup phase of the control transfer
+ */
+static int ctrlreq_setup_phase(struct usb_device *dev, struct devrequest *setup)
+{
+	int result;
+	u16 csr;
+
+	/* write the control request to ep0 fifo */
+	write_fifo(MUSB_CONTROL_EP, sizeof(struct devrequest), (void *)setup);
+
+	/* enable transfer of setup packet */
+	csr = readw(&musbr->txcsr);
+	csr |= (MUSB_CSR0_TXPKTRDY|MUSB_CSR0_H_SETUPPKT);
+	writew(csr, &musbr->txcsr);
+
+	/* wait until the setup packet is transmitted */
+	result = wait_until_ep0_ready(dev, MUSB_CSR0_TXPKTRDY);
+	dev->act_len = 0;
+	return result;
+}
+
+/*
+ * This function handles the control transfer in data phase
+ */
+static int ctrlreq_in_data_phase(struct usb_device *dev, u32 len, void *buffer)
+{
+	u16 csr;
+	u32 rxlen = 0;
+	u32 nextlen = 0;
+	u8  maxpktsize = (1 << dev->maxpacketsize) * 8;
+	u8  *rxbuff = (u8 *)buffer;
+	u8  rxedlength;
+	int result;
+
+	while (rxlen < len) {
+		/* Determine the next read length */
+		nextlen = ((len-rxlen) > maxpktsize) ? maxpktsize : (len-rxlen);
+
+		/* Set the ReqPkt bit */
+		csr = readw(&musbr->txcsr);
+		writew(csr | MUSB_CSR0_H_REQPKT, &musbr->txcsr);
+		result = wait_until_ep0_ready(dev, MUSB_CSR0_RXPKTRDY);
+		if (result < 0)
+			return result;
+
+		/* Actual number of bytes received by usb */
+		rxedlength = readb(&musbr->rxcount);
+
+		/* Read the data from the RxFIFO */
+		read_fifo(MUSB_CONTROL_EP, rxedlength, &rxbuff[rxlen]);
+
+		/* Clear the RxPktRdy Bit */
+		csr = readw(&musbr->txcsr);
+		csr &= ~MUSB_CSR0_RXPKTRDY;
+		writew(csr, &musbr->txcsr);
+
+		/* short packet? */
+		if (rxedlength != nextlen) {
+			dev->act_len += rxedlength;
+			break;
+		}
+		rxlen += nextlen;
+		dev->act_len = rxlen;
+	}
+	return 0;
+}
+
+/*
+ * This function handles the control transfer out data phase
+ */
+static int ctrlreq_out_data_phase(struct usb_device *dev, u32 len, void *buffer)
+{
+	u16 csr;
+	u32 txlen = 0;
+	u32 nextlen = 0;
+	u8  maxpktsize = (1 << dev->maxpacketsize) * 8;
+	u8  *txbuff = (u8 *)buffer;
+	int result = 0;
+
+	while (txlen < len) {
+		/* Determine the next write length */
+		nextlen = ((len-txlen) > maxpktsize) ? maxpktsize : (len-txlen);
+
+		/* Load the data to send in FIFO */
+		write_fifo(MUSB_CONTROL_EP, txlen, &txbuff[txlen]);
+
+		/* Set TXPKTRDY bit */
+		csr = readw(&musbr->txcsr);
+		writew(csr | MUSB_CSR0_H_DIS_PING | MUSB_CSR0_TXPKTRDY,
+					&musbr->txcsr);
+		result = wait_until_ep0_ready(dev, MUSB_CSR0_TXPKTRDY);
+		if (result < 0)
+			break;
+
+		txlen += nextlen;
+		dev->act_len = txlen;
+	}
+	return result;
+}
+
+/*
+ * This function handles the control transfer out status phase
+ */
+static int ctrlreq_out_status_phase(struct usb_device *dev)
+{
+	u16 csr;
+	int result;
+
+	/* Set the StatusPkt bit */
+	csr = readw(&musbr->txcsr);
+	csr |= (MUSB_CSR0_H_DIS_PING | MUSB_CSR0_TXPKTRDY |
+			MUSB_CSR0_H_STATUSPKT);
+	writew(csr, &musbr->txcsr);
+
+	/* Wait until TXPKTRDY bit is cleared */
+	result = wait_until_ep0_ready(dev, MUSB_CSR0_TXPKTRDY);
+	return result;
+}
+
+/*
+ * This function handles the control transfer in status phase
+ */
+static int ctrlreq_in_status_phase(struct usb_device *dev)
+{
+	u16 csr;
+	int result;
+
+	/* Set the StatusPkt bit and ReqPkt bit */
+	csr = MUSB_CSR0_H_DIS_PING | MUSB_CSR0_H_REQPKT | MUSB_CSR0_H_STATUSPKT;
+	writew(csr, &musbr->txcsr);
+	result = wait_until_ep0_ready(dev, MUSB_CSR0_H_REQPKT);
+
+	/* clear StatusPkt bit and RxPktRdy bit */
+	csr = readw(&musbr->txcsr);
+	csr &= ~(MUSB_CSR0_RXPKTRDY | MUSB_CSR0_H_STATUSPKT);
+	writew(csr, &musbr->txcsr);
+	return result;
+}
+
+/*
+ * determines the speed of the device (High/Full/Slow)
+ */
+static u8 get_dev_speed(struct usb_device *dev)
+{
+	return (dev->speed & USB_SPEED_HIGH) ? MUSB_TYPE_SPEED_HIGH :
+		((dev->speed & USB_SPEED_LOW) ? MUSB_TYPE_SPEED_LOW :
+						MUSB_TYPE_SPEED_FULL);
+}
+
+/*
+ * configure the hub address and the port address.
+ */
+static void config_hub_port(struct usb_device *dev, u8 ep)
+{
+	u8 chid;
+	u8 hub;
+
+	/* Find out the nearest parent which is high speed */
+	while (dev->parent->parent != NULL)
+		if (get_dev_speed(dev->parent) !=  MUSB_TYPE_SPEED_HIGH)
+			dev = dev->parent;
+		else
+			break;
+
+	/* determine the port address at that hub */
+	hub = dev->parent->devnum;
+	for (chid = 0; chid < USB_MAXCHILDREN; chid++)
+		if (dev->parent->children[chid] == dev)
+			break;
+
+	/* configure the hub address and the port address */
+	writeb(hub, &musbr->tar[ep].txhubaddr);
+	writeb((chid + 1), &musbr->tar[ep].txhubport);
+	writeb(hub, &musbr->tar[ep].rxhubaddr);
+	writeb((chid + 1), &musbr->tar[ep].rxhubport);
+}
+
+/*
+ * do a control transfer
+ */
+int submit_control_msg(struct usb_device *dev, unsigned long pipe, void *buffer,
+			int len, struct devrequest *setup)
+{
+	int devnum = usb_pipedevice(pipe);
+	u16 csr;
+	u8  devspeed;
+
+	/* select control endpoint */
+	writeb(MUSB_CONTROL_EP, &musbr->index);
+	csr = readw(&musbr->txcsr);
+
+	/* target addr and (for multipoint) hub addr/port */
+	writeb(devnum, &musbr->tar[MUSB_CONTROL_EP].txfuncaddr);
+	writeb(devnum, &musbr->tar[MUSB_CONTROL_EP].rxfuncaddr);
+
+	/* configure the hub address and the port number as required */
+	devspeed = get_dev_speed(dev);
+	if ((musb_ishighspeed()) && (dev->parent != NULL) &&
+		(devspeed != MUSB_TYPE_SPEED_HIGH)) {
+		config_hub_port(dev, MUSB_CONTROL_EP);
+		writeb(devspeed << 6, &musbr->txtype);
+	} else {
+		writeb(musb_cfg.musb_speed << 6, &musbr->txtype);
+		writeb(0, &musbr->tar[MUSB_CONTROL_EP].txhubaddr);
+		writeb(0, &musbr->tar[MUSB_CONTROL_EP].txhubport);
+		writeb(0, &musbr->tar[MUSB_CONTROL_EP].rxhubaddr);
+		writeb(0, &musbr->tar[MUSB_CONTROL_EP].rxhubport);
+	}
+
+	/* Control transfer setup phase */
+	if (ctrlreq_setup_phase(dev, setup) < 0)
+		return 0;
+
+	switch (setup->request) {
+	case USB_REQ_GET_DESCRIPTOR:
+	case USB_REQ_GET_CONFIGURATION:
+	case USB_REQ_GET_INTERFACE:
+	case USB_REQ_GET_STATUS:
+	case USB_MSC_BBB_GET_MAX_LUN:
+		/* control transfer in-data-phase */
+		if (ctrlreq_in_data_phase(dev, len, buffer) < 0)
+			return 0;
+		/* control transfer out-status-phase */
+		if (ctrlreq_out_status_phase(dev) < 0)
+			return 0;
+		break;
+
+	case USB_REQ_SET_ADDRESS:
+	case USB_REQ_SET_CONFIGURATION:
+	case USB_REQ_SET_FEATURE:
+	case USB_REQ_SET_INTERFACE:
+	case USB_REQ_CLEAR_FEATURE:
+	case USB_MSC_BBB_RESET:
+		/* control transfer in status phase */
+		if (ctrlreq_in_status_phase(dev) < 0)
+			return 0;
+		break;
+
+	case USB_REQ_SET_DESCRIPTOR:
+		/* control transfer out data phase */
+		if (ctrlreq_out_data_phase(dev, len, buffer) < 0)
+			return 0;
+		/* control transfer in status phase */
+		if (ctrlreq_in_status_phase(dev) < 0)
+			return 0;
+		break;
+
+	default:
+		/* unhandled control transfer */
+		return -1;
+	}
+
+	dev->status = 0;
+	dev->act_len = len;
+	return len;
+}
+
+/*
+ * do a bulk transfer
+ */
+int submit_bulk_msg(struct usb_device *dev, unsigned long pipe,
+					void *buffer, int len)
+{
+	int dir_out = usb_pipeout(pipe);
+	int ep = usb_pipeendpoint(pipe);
+	int devnum = usb_pipedevice(pipe);
+	u8  type;
+	u16 csr;
+	u32 txlen = 0;
+	u32 nextlen = 0;
+	u8  devspeed;
+
+	/* select bulk endpoint */
+	writeb(MUSB_BULK_EP, &musbr->index);
+
+	/* write the address of the device */
+	if (dir_out)
+		writeb(devnum, &musbr->tar[MUSB_BULK_EP].txfuncaddr);
+	else
+		writeb(devnum, &musbr->tar[MUSB_BULK_EP].rxfuncaddr);
+
+	/* configure the hub address and the port number as required */
+	devspeed = get_dev_speed(dev);
+	if ((musb_ishighspeed()) && (dev->parent != NULL) &&
+		(devspeed != MUSB_TYPE_SPEED_HIGH)) {
+		/*
+		 * MUSB is in high speed and the destination device is full
+		 * speed device. So configure the hub address and port
+		 * address registers.
+		 */
+		config_hub_port(dev, MUSB_BULK_EP);
+	} else {
+		if (dir_out) {
+			writeb(0, &musbr->tar[MUSB_BULK_EP].txhubaddr);
+			writeb(0, &musbr->tar[MUSB_BULK_EP].txhubport);
+		} else {
+			writeb(0, &musbr->tar[MUSB_BULK_EP].rxhubaddr);
+			writeb(0, &musbr->tar[MUSB_BULK_EP].rxhubport);
+		}
+		devspeed = musb_cfg.musb_speed;
+	}
+
+	/* Write the saved toggle bit value */
+	write_toggle(dev, ep, dir_out);
+
+	if (dir_out) { /* bulk-out transfer */
+		/* Program the TxType register */
+		type = (devspeed << MUSB_TYPE_SPEED_SHIFT) |
+			   (MUSB_TYPE_PROTO_BULK << MUSB_TYPE_PROTO_SHIFT) |
+			   (ep & MUSB_TYPE_REMOTE_END);
+		writeb(type, &musbr->txtype);
+
+		/* Write maximum packet size to the TxMaxp register */
+		writew(dev->epmaxpacketout[ep], &musbr->txmaxp);
+		while (txlen < len) {
+			nextlen = ((len-txlen) < dev->epmaxpacketout[ep]) ?
+					(len-txlen) : dev->epmaxpacketout[ep];
+
+			/* Write the data to the FIFO */
+			write_fifo(MUSB_BULK_EP, nextlen,
+					(void *)(((u8 *)buffer) + txlen));
+
+			/* Set the TxPktRdy bit */
+			csr = readw(&musbr->txcsr);
+			writew(csr | MUSB_TXCSR_TXPKTRDY, &musbr->txcsr);
+
+			/* Wait until the TxPktRdy bit is cleared */
+			if (!wait_until_txep_ready(dev, MUSB_BULK_EP)) {
+				readw(&musbr->txcsr);
+				usb_settoggle(dev, ep, dir_out,
+				(csr >> MUSB_TXCSR_H_DATATOGGLE_SHIFT) & 1);
+				dev->act_len = txlen;
+				return 0;
+			}
+			txlen += nextlen;
+		}
+
+		/* Keep a copy of the data toggle bit */
+		csr = readw(&musbr->txcsr);
+		usb_settoggle(dev, ep, dir_out,
+				(csr >> MUSB_TXCSR_H_DATATOGGLE_SHIFT) & 1);
+	} else { /* bulk-in transfer */
+		/* Write the saved toggle bit value */
+		write_toggle(dev, ep, dir_out);
+
+		/* Program the RxType register */
+		type = (devspeed << MUSB_TYPE_SPEED_SHIFT) |
+			   (MUSB_TYPE_PROTO_BULK << MUSB_TYPE_PROTO_SHIFT) |
+			   (ep & MUSB_TYPE_REMOTE_END);
+		writeb(type, &musbr->rxtype);
+
+		/* Write the maximum packet size to the RxMaxp register */
+		writew(dev->epmaxpacketin[ep], &musbr->rxmaxp);
+		while (txlen < len) {
+			nextlen = ((len-txlen) < dev->epmaxpacketin[ep]) ?
+					(len-txlen) : dev->epmaxpacketin[ep];
+
+			/* Set the ReqPkt bit */
+			writew(MUSB_RXCSR_H_REQPKT, &musbr->rxcsr);
+
+			/* Wait until the RxPktRdy bit is set */
+			if (!wait_until_rxep_ready(dev, MUSB_BULK_EP)) {
+				csr = readw(&musbr->rxcsr);
+				usb_settoggle(dev, ep, dir_out,
+				(csr >> MUSB_S_RXCSR_H_DATATOGGLE) & 1);
+				csr &= ~MUSB_RXCSR_RXPKTRDY;
+				writew(csr, &musbr->rxcsr);
+				dev->act_len = txlen;
+				return 0;
+			}
+
+			/* Read the data from the FIFO */
+			read_fifo(MUSB_BULK_EP, nextlen,
+					(void *)(((u8 *)buffer) + txlen));
+
+			/* Clear the RxPktRdy bit */
+			csr =  readw(&musbr->rxcsr);
+			csr &= ~MUSB_RXCSR_RXPKTRDY;
+			writew(csr, &musbr->rxcsr);
+			txlen += nextlen;
+		}
+
+		/* Keep a copy of the data toggle bit */
+		csr = readw(&musbr->rxcsr);
+		usb_settoggle(dev, ep, dir_out,
+				(csr >> MUSB_S_RXCSR_H_DATATOGGLE) & 1);
+	}
+
+	/* bulk transfer is complete */
+	dev->status = 0;
+	dev->act_len = len;
+	return 0;
+}
+
+/*
+ * This function initializes the usb controller module.
+ */
+int usb_lowlevel_init(void)
+{
+	u8  power;
+	u32 timeout;
+
+	if (musb_platform_init() == -1)
+		return -1;
+
+	/* Configure all the endpoint FIFO's and start usb controller */
+	musbr = musb_cfg.regs;
+	musb_configure_ep(&epinfo[0],
+			sizeof(epinfo) / sizeof(struct musb_epinfo));
+	musb_start();
+
+	/*
+	 * Wait until musb is enabled in host mode with a timeout. There
+	 * should be a usb device connected.
+	 */
+	timeout = musb_cfg.timeout;
+	while (timeout--)
+		if (readb(&musbr->devctl) & MUSB_DEVCTL_HM)
+			break;
+
+	/* if musb core is not in host mode, then return */
+	if (!timeout)
+		return -1;
+
+	/* start usb bus reset */
+	power = readb(&musbr->power);
+	writeb(power | MUSB_POWER_RESET, &musbr->power);
+
+	/* After initiating a usb reset, wait for about 20ms to 30ms */
+	udelay(30000);
+
+	/* stop usb bus reset */
+	power = readb(&musbr->power);
+	power &= ~MUSB_POWER_RESET;
+	writeb(power, &musbr->power);
+
+	/* Determine if the connected device is a high/full/low speed device */
+	musb_cfg.musb_speed = (readb(&musbr->power) & MUSB_POWER_HSMODE) ?
+			MUSB_TYPE_SPEED_HIGH :
+			((readb(&musbr->devctl) & MUSB_DEVCTL_FSDEV) ?
+			MUSB_TYPE_SPEED_FULL : MUSB_TYPE_SPEED_LOW);
+	return 0;
+}
+
+/*
+ * This function stops the operation of the davinci usb module.
+ */
+int usb_lowlevel_stop(void)
+{
+	/* Reset the USB module */
+	musb_platform_deinit();
+	writeb(0, &musbr->devctl);
+	return 0;
+}
+
+/*
+ * This function supports usb interrupt transfers. Currently, usb interrupt
+ * transfers are not supported.
+ */
+int submit_int_msg(struct usb_device *dev, unsigned long pipe,
+				void *buffer, int len, int interval)
+{
+	int dir_out = usb_pipeout(pipe);
+	int ep = usb_pipeendpoint(pipe);
+	int devnum = usb_pipedevice(pipe);
+	u8  type;
+	u16 csr;
+	u32 txlen = 0;
+	u32 nextlen = 0;
+	u8  devspeed;
+
+	/* select interrupt endpoint */
+	writeb(MUSB_INTR_EP, &musbr->index);
+
+	/* write the address of the device */
+	if (dir_out)
+		writeb(devnum, &musbr->tar[MUSB_INTR_EP].txfuncaddr);
+	else
+		writeb(devnum, &musbr->tar[MUSB_INTR_EP].rxfuncaddr);
+
+	/* configure the hub address and the port number as required */
+	devspeed = get_dev_speed(dev);
+	if ((musb_ishighspeed()) && (dev->parent != NULL) &&
+		(devspeed != MUSB_TYPE_SPEED_HIGH)) {
+		/*
+		 * MUSB is in high speed and the destination device is full
+		 * speed device. So configure the hub address and port
+		 * address registers.
+		 */
+		config_hub_port(dev, MUSB_INTR_EP);
+	} else {
+		if (dir_out) {
+			writeb(0, &musbr->tar[MUSB_INTR_EP].txhubaddr);
+			writeb(0, &musbr->tar[MUSB_INTR_EP].txhubport);
+		} else {
+			writeb(0, &musbr->tar[MUSB_INTR_EP].rxhubaddr);
+			writeb(0, &musbr->tar[MUSB_INTR_EP].rxhubport);
+		}
+		devspeed = musb_cfg.musb_speed;
+	}
+
+	/* Write the saved toggle bit value */
+	write_toggle(dev, ep, dir_out);
+
+	if (!dir_out) { /* intrrupt-in transfer */
+		/* Write the saved toggle bit value */
+		write_toggle(dev, ep, dir_out);
+		writeb(interval, &musbr->rxinterval);
+
+		/* Program the RxType register */
+		type = (devspeed << MUSB_TYPE_SPEED_SHIFT) |
+			   (MUSB_TYPE_PROTO_INTR << MUSB_TYPE_PROTO_SHIFT) |
+			   (ep & MUSB_TYPE_REMOTE_END);
+		writeb(type, &musbr->rxtype);
+
+		/* Write the maximum packet size to the RxMaxp register */
+		writew(dev->epmaxpacketin[ep], &musbr->rxmaxp);
+
+		while (txlen < len) {
+			nextlen = ((len-txlen) < dev->epmaxpacketin[ep]) ?
+					(len-txlen) : dev->epmaxpacketin[ep];
+
+			/* Set the ReqPkt bit */
+			writew(MUSB_RXCSR_H_REQPKT, &musbr->rxcsr);
+
+			/* Wait until the RxPktRdy bit is set */
+			if (!wait_until_rxep_ready(dev, MUSB_INTR_EP)) {
+				csr = readw(&musbr->rxcsr);
+				usb_settoggle(dev, ep, dir_out,
+				(csr >> MUSB_S_RXCSR_H_DATATOGGLE) & 1);
+				csr &= ~MUSB_RXCSR_RXPKTRDY;
+				writew(csr, &musbr->rxcsr);
+				dev->act_len = txlen;
+				return 0;
+			}
+
+			/* Read the data from the FIFO */
+			read_fifo(MUSB_INTR_EP, nextlen,
+					(void *)(((u8 *)buffer) + txlen));
+
+			/* Clear the RxPktRdy bit */
+			csr =  readw(&musbr->rxcsr);
+			csr &= ~MUSB_RXCSR_RXPKTRDY;
+			writew(csr, &musbr->rxcsr);
+			txlen += nextlen;
+		}
+
+		/* Keep a copy of the data toggle bit */
+		csr = readw(&musbr->rxcsr);
+		usb_settoggle(dev, ep, dir_out,
+				(csr >> MUSB_S_RXCSR_H_DATATOGGLE) & 1);
+	}
+
+	/* interrupt transfer is complete */
+	dev->irq_status = 0;
+	dev->irq_act_len = len;
+	dev->irq_handle(dev);
+	dev->status = 0;
+	dev->act_len = len;
+	return 0;
+}
+
+
+#ifdef CONFIG_SYS_USB_EVENT_POLL
+/*
+ * This function polls for USB keyboard data.
+ */
+void usb_event_poll()
+{
+	device_t *dev;
+	struct usb_device *usb_kbd_dev;
+	struct usb_interface_descriptor *iface;
+	struct usb_endpoint_descriptor *ep;
+	int pipe;
+	int maxp;
+
+	/* Get the pointer to USB Keyboard device pointer */
+	dev = device_get_by_name("usbkbd");
+	usb_kbd_dev = (struct usb_device *)dev->priv;
+	iface = &usb_kbd_dev->config.if_desc[0];
+	ep = &iface->ep_desc[0];
+	pipe = usb_rcvintpipe(usb_kbd_dev, ep->bEndpointAddress);
+
+	/* Submit a interrupt transfer request */
+	maxp = usb_maxpacket(usb_kbd_dev, pipe);
+	usb_submit_int_msg(usb_kbd_dev, pipe, &new[0],
+			maxp > 8 ? 8 : maxp, ep->bInterval);
+}
+#endif /* CONFIG_SYS_USB_EVENT_POLL */