rockbox/firmware/target/arm/rk27xx/usb-drv-rk27xx.c

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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2011 by Marcin Bukat
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "config.h"
#include "usb.h"
#include "usb_drv.h"
#include "cpu.h"
#include "system.h"
#include "kernel.h"
#include "panic.h"
//#include "usb-s3c6400x.h"
#include "usb_ch9.h"
#include "usb_core.h"
#include <inttypes.h>
#include "power.h"
#include "logf.h"
typedef volatile uint32_t reg32;
/* Bulk OUT: ep1, ep4, ep7, ep10, ep13 */
#define BOUT_RXSTAT(ep_num) (*(reg32*)(AHB0_UDC+0x54+0x38*(ep_num/3)))
#define BOUT_RXCON(ep_num) (*(reg32*)(AHB0_UDC+0x58+0x38*(ep_num/3)))
#define BOUT_DMAOUTCTL(ep_num) (*(reg32*)(AHB0_UDC+0x5C+0x38*(ep_num/3)))
#define BOUT_DMAOUTLMADDR(ep_num) (*(reg32*)(AHB0_UDC+0x60+0x38*(ep_num/3)))
/* Bulk IN: ep2, ep5, ep8, ep11, ep4 */
#define BIN_TXSTAT(ep_num) (*(reg32*)(AHB0_UDC+0x64+0x38*(ep_num/3)))
#define BIN_TXCON(ep_num) (*(reg32*)(AHB0_UDC+0x68+0x38*(ep_num/3)))
#define BIN_TXBUF(ep_num) (*(reg32*)(AHB0_UDC+0x6C+0x38*(ep_num/3)))
#define BIN_DMAINCTL(ep_num) (*(reg32*)(AHB0_UDC+0x70+0x38*(ep_num/3)))
#define BIN_DMAINLMADDR(ep_num) (*(reg32*)(AHB0_UDC+0x74+0x38*(ep_num/3)))
/* INTERRUPT IN: ep3, ep6, ep9, ep12, ep15 */
#define IIN_TXSTAT(ep_num) (*(reg32*)(AHB0_UDC+0x78+0x38*((ep_num/3)-1)))
#define IIN_TXCON(ep_num) (*(reg32*)(AHB0_UDC+0x7C+0x38*((ep_num/3)-1)))
#define IIN_TXBUF(ep_num) (*(reg32*)(AHB0_UDC+0x80+0x38*((ep_num/3)-1)))
#define IIN_DMAINCTL(ep_num) (*(reg32*)(AHB0_UDC+0x84+0x38*((ep_num/3)-1)))
#define IIN_DMAINLMADDR(ep_num) (*(reg32*)(AHB0_UDC+0x88+0x38*((ep_num/3)-1)))
#ifdef LOGF_ENABLE
#define XFER_DIR_STR(dir) ((dir) ? "IN" : "OUT")
#endif
struct endpoint_t {
const int type; /* EP type */
const int dir; /* DIR_IN/DIR_OUT */
bool allocated; /* flag to mark EPs taken */
volatile void *buf; /* tx/rx buffer address */
volatile int len; /* size of the transfer (bytes) */
volatile int cnt; /* number of bytes transfered/received */
volatile bool block; /* flag indicating that transfer is blocking */
struct semaphore complete; /* semaphore for blocking transfers */
};
static struct endpoint_t ctrlep[2] = {
{USB_ENDPOINT_XFER_CONTROL, DIR_OUT, true, NULL, 0, 0, true, {0, 0, 0}},
{USB_ENDPOINT_XFER_CONTROL, DIR_IN, true, NULL, 0, 0, true, {0, 0, 0}}
};
static struct endpoint_t endpoints[16] = {
{USB_ENDPOINT_XFER_CONTROL, 3, true, NULL, 0, 0, true, {0, 0, 0}}, /* stub */
{USB_ENDPOINT_XFER_BULK, DIR_OUT, false, NULL, 0, 0, false, {0, 0, 0}}, /* BOUT1 */
{USB_ENDPOINT_XFER_BULK, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* BIN2 */
{USB_ENDPOINT_XFER_INT, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* IIN3 */
{USB_ENDPOINT_XFER_BULK, DIR_OUT, false, NULL, 0, 0, false, {0, 0, 0}}, /* BOUT4 */
{USB_ENDPOINT_XFER_BULK, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* BIN5 */
{USB_ENDPOINT_XFER_INT, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* IIN6 */
{USB_ENDPOINT_XFER_BULK, DIR_OUT, false, NULL, 0, 0, false, {0, 0, 0}}, /* BOUT7 */
{USB_ENDPOINT_XFER_BULK, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* BIN8 */
{USB_ENDPOINT_XFER_INT, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* IIN9 */
{USB_ENDPOINT_XFER_BULK, DIR_OUT, false, NULL, 0, 0, false, {0, 0, 0}}, /* BOUT10 */
{USB_ENDPOINT_XFER_BULK, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* BIN11 */
{USB_ENDPOINT_XFER_INT, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* IIN12 */
{USB_ENDPOINT_XFER_BULK, DIR_OUT, false, NULL, 0, 0, false, {0, 0, 0}}, /* BOUT13 */
{USB_ENDPOINT_XFER_BULK, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* BIN14 */
{USB_ENDPOINT_XFER_INT, DIR_IN, false, NULL, 0, 0, false, {0, 0, 0}}, /* IIN15 */
};
static void setup_received(void)
{
static uint32_t setup_data[2];
/* copy setup data from packet */
setup_data[0] = SETUP1;
setup_data[1] = SETUP2;
/* clear all pending control transfers
* do we need this here?
*/
/* pass setup data to the upper layer */
usb_core_control_request((struct usb_ctrlrequest*)setup_data);
}
/* service ep0 IN transaction */
static void ctr_write(void)
{
int xfer_size = (ctrlep[DIR_IN].cnt > 64) ? 64 : ctrlep[DIR_IN].cnt;
unsigned int timeout = current_tick + HZ/10;
while (TX0BUF & (1<<0)) /* TX0FULL flag */
{
if(TIME_AFTER(current_tick, timeout))
break;
}
TX0STAT = xfer_size; /* size of the transfer */
TX0DMALM_IADDR = (uint32_t)ctrlep[DIR_IN].buf; /* local buffer address */
TX0DMAINCTL = (1<<1); /* start DMA */
TX0CON &= ~(1<<2); /* clear NAK */
/* Decrement by max packet size is intentional.
* This way if we have final packet short one we will get negative len
* after transfer, which in turn indicates we *don't* need to send
* zero length packet. If the final packet is max sized packet we will
* get zero len after transfer which indicates we need to send
* zero length packet to signal host end of the transfer.
*/
ctrlep[DIR_IN].cnt -= 64;
ctrlep[DIR_IN].buf += xfer_size;
}
static void ctr_read(void)
{
int xfer_size = RX0STAT & 0xffff;
/* clear NAK bit */
RX0CON &= ~(1<<3);
ctrlep[DIR_OUT].cnt -= xfer_size;
ctrlep[DIR_OUT].buf += xfer_size;
RX0DMAOUTLMADDR = (uint32_t)ctrlep[DIR_OUT].buf;
RX0DMACTLO = (1<<0);
}
static void blk_write(int ep)
{
int ep_num = EP_NUM(ep);
int max = usb_drv_port_speed() ? 512 : 64;
int xfer_size = (endpoints[ep_num].cnt > max) ? max : endpoints[ep_num].cnt;
unsigned int timeout = current_tick + HZ/10;
while (BIN_TXBUF(ep_num) & (1<<0)) /* TXFULL flag */
{
if(TIME_AFTER(current_tick, timeout))
break;
}
BIN_TXSTAT(ep_num) = xfer_size; /* size of the transfer */
BIN_DMAINLMADDR(ep_num) = (uint32_t)endpoints[ep_num].buf; /* buf address */
BIN_DMAINCTL(ep_num) = (1<<0); /* start DMA */
BIN_TXCON(ep_num) &= ~(1<<2); /* clear NAK */
/* Decrement by max packet size is intentional.
* This way if we have final packet short one we will get negative len
* after transfer, which in turn indicates we *don't* need to send
* zero length packet. If the final packet is max sized packet we will
* get zero len after transfer which indicates we need to send
* zero length packet to signal host end of the transfer.
*/
endpoints[ep_num].cnt -= max;
endpoints[ep_num].buf += xfer_size;
}
static void blk_read(int ep)
{
int ep_num = EP_NUM(ep);
int xfer_size = BOUT_RXSTAT(ep_num) & 0xffff;
/* clear NAK bit */
BOUT_RXCON(ep_num) &= ~(1<<3);
endpoints[ep_num].cnt -= xfer_size;
endpoints[ep_num].buf += xfer_size;
BOUT_DMAOUTLMADDR(ep_num) = (uint32_t)endpoints[ep_num].buf;
BOUT_DMAOUTCTL(ep_num) = (1<<1);
}
static void int_write(int ep)
{
int ep_num = EP_NUM(ep);
int max = usb_drv_port_speed() ? 1024 : 64;
int xfer_size = (endpoints[ep_num].cnt > max) ? max : endpoints[ep_num].cnt;
unsigned int timeout = current_tick + HZ/10;
while (IIN_TXBUF(ep_num) & (1<<0)) /* TXFULL flag */
{
if(TIME_AFTER(current_tick, timeout))
break;
}
IIN_TXSTAT(ep_num) = xfer_size; /* size of the transfer */
IIN_DMAINLMADDR(ep_num) = (uint32_t)endpoints[ep_num].buf; /* buf address */
IIN_DMAINCTL(ep_num) = (1<<0); /* start DMA */
IIN_TXCON(ep_num) &= ~(1<<2); /* clear NAK */
/* Decrement by max packet size is intentional.
* This way if we have final packet short one we will get negative len
* after transfer, which in turn indicates we *don't* need to send
* zero length packet. If the final packet is max sized packet we will
* get zero len after transfer which indicates we need to send
* zero length packet to signal host end of the transfer.
*/
endpoints[ep_num].cnt -= max;
endpoints[ep_num].buf += xfer_size;
}
/* UDC ISR function */
void INT_UDC(void)
{
uint32_t txstat, rxstat;
int tmp, ep_num;
/* read what caused UDC irq */
uint32_t intsrc = INT2FLAG & 0x7fffff;
if (intsrc & (1<<1)) /* setup interrupt */
{
setup_received();
}
else if (intsrc & (1<<2)) /* ep0 in interrupt */
{
txstat = TX0STAT; /* read clears flags */
/* TODO handle errors */
if (txstat & (1<<18)) /* check TxACK flag */
{
if (ctrlep[DIR_IN].cnt >= 0)
{
/* we still have data to send (or ZLP) */
ctr_write();
}
else
{
/* final ack received */
usb_core_transfer_complete(0, /* ep */
USB_DIR_IN, /* dir */
0, /* status */
ctrlep[DIR_IN].len); /* length */
/* release semaphore for blocking transfer */
if (ctrlep[DIR_IN].block)
semaphore_release(&ctrlep[DIR_IN].complete);
}
}
}
else if (intsrc & (1<<3)) /* ep0 out interrupt */
{
rxstat = RX0STAT;
/* TODO handle errors */
if (rxstat & (1<<18)) /* RxACK */
{
if (ctrlep[DIR_OUT].cnt > 0)
ctr_read();
else
usb_core_transfer_complete(0, /* ep */
USB_DIR_OUT, /* dir */
0, /* status */
ctrlep[DIR_OUT].len); /* length */
}
}
else if (intsrc & (1<<4)) /* usb reset */
{
usb_drv_init();
}
else if (intsrc & (1<<5)) /* usb resume */
{
TX0CON |= (1<<0); /* TxClr */
TX0CON &= ~(1<<0);
RX0CON |= (1<<1); /* RxClr */
RX0CON &= (1<<1);
}
else if (intsrc & (1<<6)) /* usb suspend */
{
}
else if (intsrc & (1<<7)) /* usb connect */
{
}
else
{
/* lets figure out which ep generated irq */
tmp = intsrc >> 7;
for (ep_num=1; ep_num < 15; ep_num++)
{
tmp >>= ep_num;
if (tmp & 0x01)
break;
}
if (intsrc & ((1<<8)|(1<<11)|(1<<14)|(1<<17)|(1<<20)))
{
/* bulk out */
rxstat = BOUT_RXSTAT(ep_num);
/* TODO handle errors */
if (rxstat & (1<<18)) /* RxACK */
{
if (endpoints[ep_num].cnt > 0)
blk_read(ep_num);
else
usb_core_transfer_complete(ep_num, /* ep */
USB_DIR_OUT, /* dir */
0, /* status */
endpoints[ep_num].len); /* length */
}
}
else if (intsrc & ((1<<9)|(1<<12)|(1<<15)|(1<<18)|(1<<21)))
{
/* bulk in */
txstat = BIN_TXSTAT(ep_num);
/* TODO handle errors */
if (txstat & (1<<18)) /* check TxACK flag */
{
if (endpoints[ep_num].cnt >= 0)
{
/* we still have data to send (or ZLP) */
blk_write(ep_num);
}
else
{
/* final ack received */
usb_core_transfer_complete(ep_num, /* ep */
USB_DIR_IN, /* dir */
0, /* status */
endpoints[ep_num].len); /* length */
/* release semaphore for blocking transfer */
if (endpoints[ep_num].block)
semaphore_release(&endpoints[ep_num].complete);
}
}
}
else if (intsrc & ((1<<10)|(1<13)|(1<<16)|(1<<19)|(1<<22)))
{
/* int in */
txstat = IIN_TXSTAT(ep_num);
/* TODO handle errors */
if (txstat & (1<<18)) /* check TxACK flag */
{
if (endpoints[ep_num].cnt >= 0)
{
/* we still have data to send (or ZLP) */
int_write(ep_num);
}
else
{
/* final ack received */
usb_core_transfer_complete(ep_num, /* ep */
USB_DIR_IN, /* dir */
0, /* status */
endpoints[ep_num].len); /* length */
/* release semaphore for blocking transfer */
if (endpoints[ep_num].block)
semaphore_release(&endpoints[ep_num].complete);
}
}
}
}
}
/* return port speed FS=0, HS=1 */
int usb_drv_port_speed(void)
{
return ((DEV_INFO & (3<<21)) == 0) ? 0 : 1;
}
/* Reserve endpoint */
int usb_drv_request_endpoint(int type, int dir)
{
int ep_num, ep_dir;
int ep_type;
/* Safety */
ep_dir = EP_DIR(dir);
ep_type = type & USB_ENDPOINT_XFERTYPE_MASK;
logf("req: %s %s", XFER_DIR_STR(ep_dir), XFER_TYPE_STR(ep_type));
/* Find an available ep/dir pair */
for (ep_num=1;ep_num<USB_NUM_ENDPOINTS;ep_num++)
{
struct endpoint_t* endpoint = &endpoints[ep_num];
if (endpoint->type == ep_type &&
endpoint->dir == ep_dir &&
!endpoint->allocated)
{
/* mark endpoint as taken */
endpoint->allocated = true;
/* enable interrupt from this endpoint */
EN_INT |= (1<<(ep_num+7));
logf("add: ep%d %s", ep_num, XFER_DIR_STR(ep_dir));
return (ep_num | (dir & USB_ENDPOINT_DIR_MASK));
}
}
return -1;
}
/* Free endpoint */
void usb_drv_release_endpoint(int ep)
{
int ep_num = EP_NUM(ep);
int ep_dir = EP_DIR(ep);
(void) ep_dir;
logf("rel: ep%d %s", ep_num, XFER_DIR_STR(ep_dir));
endpoints[ep_num].allocated = false;
/* disable interrupt from this endpoint */
EN_INT &= ~(1<<(ep_num+7));
}
/* Set the address (usually it's in a register).
* There is a problem here: some controller want the address to be set between
* control out and ack and some want to wait for the end of the transaction.
* In the first case, you need to write some code special code when getting
* setup packets and ignore this function (have a look at other drives)
*/
void usb_drv_set_address(int address)
{
(void)address;
/* UDC seems to set this automaticaly */
}
static int _usb_drv_send(int endpoint, void *ptr, int length, bool block)
{
struct endpoint_t *ep;
int ep_num = EP_NUM(endpoint);
if (ep_num == 0)
ep = &ctrlep[DIR_IN];
else
ep = &endpoints[ep_num];
ep->buf = ptr;
ep->len = ep->cnt = length;
if (block)
ep->block = true;
else
ep->block = false;
switch (ep->type)
{
case USB_ENDPOINT_XFER_CONTROL:
ctr_write();
break;
case USB_ENDPOINT_XFER_BULK:
blk_write(ep_num);
break;
case USB_ENDPOINT_XFER_INT:
int_write(ep_num);
break;
}
if (block)
/* wait for transfer to end */
semaphore_wait(&ep->complete, TIMEOUT_BLOCK);
return 0;
}
/* Setup a send transfer. (blocking) */
int usb_drv_send(int endpoint, void *ptr, int length)
{
return _usb_drv_send(endpoint, ptr, length, true);
}
/* Setup a send transfer. (non blocking) */
int usb_drv_send_nonblocking(int endpoint, void *ptr, int length)
{
return _usb_drv_send(endpoint, ptr, length, false);
}
/* Setup a receive transfer. (non blocking) */
int usb_drv_recv(int endpoint, void* ptr, int length)
{
struct endpoint_t *ep;
int ep_num = EP_NUM(endpoint);
if (ep_num == 0)
{
ep = &ctrlep[DIR_OUT];
ctr_read();
}
else
{
ep = &endpoints[ep_num];
/* clear NAK bit */
BOUT_RXCON(ep_num) &= ~(1<<3);
BOUT_DMAOUTLMADDR(ep_num) = (uint32_t)ptr;
BOUT_DMAOUTCTL(ep_num) = (1<<1);
}
ep->buf = ptr;
ep->len = ep->cnt = length;
return 0;
}
/* Kill all transfers. Usually you need to set a bit for each endpoint
* and flush fifos. You should also call the completion handler with
* error status for everything
*/
void usb_drv_cancel_all_transfers(void)
{
}
/* Set test mode, you can forget that for now, usually it's sufficient
* to bit copy the argument into some register of the controller
*/
void usb_drv_set_test_mode(int mode)
{
(void)mode;
}
/* Check if endpoint is in stall state */
bool usb_drv_stalled(int endpoint, bool in)
{
int ep_num = EP_NUM(endpoint);
switch (endpoints[ep_num].type)
{
case USB_ENDPOINT_XFER_CONTROL:
if (in)
return (TX0CON & (1<<1)) ? true : false;
else
return (RX0CON & (1<<2)) ? true : false;
break;
case USB_ENDPOINT_XFER_BULK:
if (in)
return (BIN_TXCON(ep_num) & (1<<1)) ? true : false;
else
return (BOUT_RXCON(ep_num) & (1<<2)) ? true : false;
break;
case USB_ENDPOINT_XFER_INT:
if (in)
return (IIN_TXCON(ep_num) & (1<<1)) ? true : false;
else
return false; /* we don't have such endpoint anyway */
break;
}
return false;
}
/* Stall the endpoint. Usually set a flag in the controller */
void usb_drv_stall(int endpoint, bool stall, bool in)
{
int ep_num = EP_NUM(endpoint);
switch (endpoints[ep_num].type)
{
case USB_ENDPOINT_XFER_CONTROL:
if (in)
{
if (stall)
TX0CON |= (1<<1);
else
TX0CON &= ~(1<<1);
}
else
{
if (stall)
RX0CON |= (1<<2);
else
RX0CON &= ~(1<<2); /* doc says Auto clear by UDC 2.0 */
}
break;
case USB_ENDPOINT_XFER_BULK:
if (in)
{
if (stall)
BIN_TXCON(ep_num) |= (1<<1);
else
BIN_TXCON(ep_num) &= ~(1<<1);
}
else
{
if (stall)
BOUT_RXCON(ep_num) |= (1<<2);
else
BOUT_RXCON(ep_num) &= ~(1<<2);
}
break;
case USB_ENDPOINT_XFER_INT:
if (in)
{
if (stall)
IIN_TXCON(ep_num) |= (1<<1);
else
IIN_TXCON(ep_num) &= ~(1<<1);
}
break;
}
}
/* one time init (once per connection) - basicaly enable usb core */
void usb_drv_init(void)
{
int ep_num;
/* enable USB clock */
SCU_CLKCFG &= ~(1<<6);
/* 1. do soft disconnect */
DEV_CTL = (1<<3); /* DEV_SELF_PWR */
/* 2. do power on reset to PHY */
DEV_CTL = (1<<3) | /* DEV_SELF_PWR */
(1<<7); /* SOFT_POR */
/* 3. wait more than 10ms */
udelay(20000);
/* 4. clear SOFT_POR bit */
DEV_CTL &= ~(1<<7);
/* 5. configure minimal EN_INT */
EN_INT = (1<<6) | /* Enable Suspend Interrupt */
(1<<5) | /* Enable Resume Interrupt */
(1<<4) | /* Enable USB Reset Interrupt */
(1<<3) | /* Enable OUT Token receive Interrupt EP0 */
(1<<2) | /* Enable IN Token transmits Interrupt EP0 */
(1<<1); /* Enable SETUP Packet Receive Interrupt */
/* 6. configure INTCON */
INTCON = (1<<2) | /* interrupt high active */
(1<<0); /* enable EP0 interrupts */
/* 7. configure EP0 control registers */
TX0CON = (1<<6) | /* Set as one to enable the EP0 tx irq */
(1<<2); /* Set as one to response NAK handshake */
RX0CON = (1<<7) |
(1<<4) | /* Endpoint 0 Enable. When cleared the endpoint does
* not respond to an SETUP or OUT token
*/
(1<<3); /* Set as one to response NAK handshake */
/* 8. write final bits to DEV_CTL */
DEV_CTL = (1<<8) | /* Configure CSR done */
(1<<6) | /* 16-bit data path enabled. udc_clk = 30MHz */
(1<<4) | /* Device soft connect */
(1<<3); /* Device self power */
/* init semaphore of ep0 */
semaphore_init(&ctrlep[DIR_OUT].complete, 1, 0);
semaphore_init(&ctrlep[DIR_IN].complete, 1, 0);
for (ep_num = 1; ep_num < USB_NUM_ENDPOINTS; ep_num++)
{
semaphore_init(&endpoints[ep_num].complete, 1, 0);
if (ep_num%3 == 0) /* IIN 3, 6, 9, 12, 15 */
{
IIN_TXCON(ep_num) |= (ep_num<<8)|(1<<3)|(1<<2); /* ep_num, enable, NAK */
}
else if (ep_num%3 == 1) /* BOUT 1, 4, 7, 10, 13 */
{
BOUT_RXCON(ep_num) |= (ep_num<<8)|(1<<4)|(1<<3); /* ep_num, NAK, enable */
}
else if (ep_num%3 == 2) /* BIN 2, 5, 8, 11, 14 */
{
BIN_TXCON(ep_num) |= (ep_num<<8)|(1<<3)|(1<<2); /* ep_num, enable, NAK */
}
}
}
/* turn off usb core */
void usb_drv_exit(void)
{
DEV_CTL = (1<<3); /* DEV_SELF_PWR */
/* disable USB interrupts in interrupt controller */
INTC_IMR &= ~(1<<16);
INTC_IECR &= ~(1<<16);
/* we cannot disable UDC clock since this causes data abort
* when reading DEV_INFO in order to check usb connect event
*/
}
int usb_detect(void)
{
if (DEV_INFO & (1<<20))
return USB_INSERTED;
else
return USB_EXTRACTED;
}