/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT 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 3 of the License, or
(at your option) any later version.
ChibiOS/RT 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, see <http://www.gnu.org/licenses/>.
*/
/*-*
* @file usb_msc.c
* @brief USB Mass Storage Class code.
*
* @addtogroup USB_MSC
* @{
*/
#include "ch.h"
#include "hal.h"
#include "usb_msc.h"
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/**
* @brief Zero-filled constant buffer.
*/
static const uint8_t zerobuf[4] = {0, 0, 0, 0};
/**
* @brief Answer to the INQUIRY command.
*/
static const uint8_t scsi_inquiry_data[] = {
0x00, /* Direct Access Device. */
0x80, /* RMB = 1: Removable Medium. */
0x02, /* ISO, ECMA, ANSI = 2. */
0x00, /* UFI response format. */
36 - 4, /* Additional Length. */
0x00,
0x00,
0x00,
/* Vendor Identification */
'C', 'h', 'i', 'b', 'i', 'O', 'S', ' ',
/* Product Identification */
'S', 'D', ' ', 'F', 'l', 'a', 's', 'h',
' ', 'D', 'i', 's', 'k', ' ', ' ', ' ',
/* Product Revision Level */
'1', '.', '0', ' '
};
/**
* @brief Generic buffer.
*/
uint8_t buf[16];
/*===========================================================================*/
/* MMC interface code. */
/*===========================================================================*/
/*===========================================================================*/
/* SCSI emulation code. */
/*===========================================================================*/
static uint8_t scsi_read_format_capacities(uint32_t *nblocks,
uint32_t *secsize) {
*nblocks = 1024;
*secsize = 512;
return 3; /* No Media.*/
}
/*===========================================================================*/
/* Mass Storage Class related code. */
/*===========================================================================*/
/**
* @brief MSC state machine current state.
*/
static mscstate_t msc_state;
/**
* @brief Received CBW.
*/
static msccbw_t CBW;
/**
* @brief CSW to be transmitted.
*/
static msccsw_t CSW;
/**
* @brief MSC state machine initialization.
*
* @param[in] usbp pointer to the @p USBDriver object
*/
static void msc_reset(USBDriver *usbp) {
msc_state = MSC_IDLE;
chSysLockFromIsr();
usbStartReceiveI(usbp, MSC_DATA_OUT_EP, (uint8_t *)&CBW, sizeof CBW);
chSysUnlockFromIsr();
}
static void msc_transmit(USBDriver *usbp, const uint8_t *p, size_t n) {
if (n > CBW.dCBWDataTransferLength)
n = CBW.dCBWDataTransferLength;
CSW.dCSWDataResidue = CBW.dCBWDataTransferLength - (uint32_t)n;
chSysLockFromIsr();
usbStartTransmitI(usbp, MSC_DATA_IN_EP, p, n);
chSysUnlockFromIsr();
}
static void msc_sendstatus(USBDriver *usbp) {
msc_state = MSC_SENDING_CSW;
chSysLockFromIsr();
usbStartTransmitI(usbp, MSC_DATA_IN_EP, (uint8_t *)&CSW, sizeof CSW);
chSysUnlockFromIsr();
}
static bool_t msc_decode(USBDriver *usbp) {
uint32_t nblocks, secsize;
switch (CBW.CBWCB[0]) {
case SCSI_REQUEST_SENSE:
break;
case SCSI_INQUIRY:
msc_transmit(usbp, (uint8_t *)&scsi_inquiry_data,
sizeof scsi_inquiry_data);
CSW.bCSWStatus = MSC_CSW_STATUS_PASSED;
break;
case SCSI_READ_FORMAT_CAPACITIES:
buf[8] = scsi_read_format_capacities(&nblocks, &secsize);
buf[0] = buf[1] = buf[2] = 0;
buf[3] = 8;
buf[4] = (uint8_t)(nblocks >> 24);
buf[5] = (uint8_t)(nblocks >> 16);
buf[6] = (uint8_t)(nblocks >> 8);
buf[7] = (uint8_t)(nblocks >> 0);
buf[9] = (uint8_t)(secsize >> 16);
buf[10] = (uint8_t)(secsize >> 8);
buf[11] = (uint8_t)(secsize >> 0);
msc_transmit(usbp, buf, 12);
CSW.bCSWStatus = MSC_CSW_STATUS_PASSED;
break;
default:
return TRUE;
}
return FALSE;
}
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Default requests hook.
* @details The application must use this function as callback for the
* messages hook.
* The following requests are emulated:
* - MSC_GET_MAX_LUN_COMMAND.
* - MSC_MASS_STORAGE_RESET_COMMAND.
* .
*
* @param[in] usbp pointer to the @p USBDriver object
* @return The hook status.
* @retval TRUE Message handled internally.
* @retval FALSE Message not handled.
*/
bool_t mscRequestsHook(USBDriver *usbp) {
if ((usbp->setup[0] & (USB_RTYPE_TYPE_MASK | USB_RTYPE_RECIPIENT_MASK)) ==
(USB_RTYPE_TYPE_CLASS | USB_RTYPE_RECIPIENT_INTERFACE)) {
switch (usbp->setup[1]) {
case MSC_GET_MAX_LUN_COMMAND:
usbSetupTransfer(usbp, (uint8_t *)zerobuf, 1, NULL);
return TRUE;
case MSC_MASS_STORAGE_RESET_COMMAND:
msc_reset(usbp);
usbSetupTransfer(usbp, NULL, 0, NULL);
return TRUE;
default:
return FALSE;
}
}
return FALSE;
}
/**
* @brief Default data transmitted callback.
* @details The application must use this function as callback for the IN
* data endpoint.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*/
void mscDataTransmitted(USBDriver *usbp, usbep_t ep) {
switch (msc_state) {
case MSC_DATA_IN:
CSW.dCSWSignature = MSC_CSW_SIGNATURE;
CSW.dCSWTag = CBW.dCBWTag;
chSysLockFromIsr();
usbStartTransmitI(usbp, ep, (uint8_t *)&CSW, sizeof CSW);
chSysUnlockFromIsr();
msc_state = MSC_SENDING_CSW;
break;
case MSC_SENDING_CSW:
chSysLockFromIsr();
usbStartReceiveI(usbp, MSC_DATA_OUT_EP, (uint8_t *)&CBW, sizeof CBW);
chSysUnlockFromIsr();
msc_state = MSC_IDLE;
break;
default:
;
}
}
/**
* @brief Default data received callback.
* @details The application must use this function as callback for the OUT
* data endpoint.
*
* @param[in] usbp pointer to the @p USBDriver object
* @param[in] ep endpoint number
*/
void mscDataReceived(USBDriver *usbp, usbep_t ep) {
size_t n;
n = usbGetReceiveTransactionSizeI(usbp, ep);
switch (msc_state) {
case MSC_IDLE:
if ((n != sizeof(msccbw_t)) || (CBW.dCBWSignature != MSC_CBW_SIGNATURE))
goto stall_out; /* 6.6.1 */
/* Decoding SCSI command.*/
if (msc_decode(usbp)) {
if (CBW.dCBWDataTransferLength == 0) {
CSW.bCSWStatus = MSC_CSW_STATUS_FAILED;
CSW.dCSWDataResidue = 0;
msc_sendstatus(usbp);
return;
}
goto stall_both;
}
/* Commands with zero transfer length, 5.1.*/
if (CBW.dCBWDataTransferLength == 0) {
msc_sendstatus(usbp);
return;
}
/* Transfer direction.*/
if (CBW.bmCBWFlags & 0x80) {
/* IN, Device to Host.*/
msc_state = MSC_DATA_IN;
}
else {
/* OUT, Host to Device.*/
msc_state = MSC_DATA_OUT;
}
break;
case MSC_DATA_OUT:
break;
default:
;
}
return;
stall_out:
msc_state = MSC_ERROR;
chSysLockFromIsr();
usbStallReceiveI(usbp, ep);
chSysUnlockFromIsr();
return;
stall_both:
msc_state = MSC_ERROR;
chSysLockFromIsr();
usbStallTransmitI(usbp, ep);
usbStallReceiveI(usbp, ep);
chSysUnlockFromIsr();
return;
}
/** @} */