/*
* Support for emulating SAT (ata pass through) on devices based
* on the Cypress USB/ATA bridge supporting ATACB.
*
* Copyright (c) 2008 Matthieu Castet (castet.matthieu@free.fr)
*
* 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, 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.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_eh.h>
#include <linux/ata.h>
#include "usb.h"
#include "protocol.h"
#include "scsiglue.h"
#include "debug.h"
/*
* ATACB is a protocol used on cypress usb<->ata bridge to
* send raw ATA command over mass storage
* There is a ATACB2 protocol that support LBA48 on newer chip.
* More info that be found on cy7c68310_8.pdf and cy7c68300c_8.pdf
* datasheet from cypress.com.
*/
void cypress_atacb_passthrough(struct scsi_cmnd *srb, struct us_data *us)
{
unsigned char save_cmnd[MAX_COMMAND_SIZE];
if (likely(srb->cmnd[0] != ATA_16 && srb->cmnd[0] != ATA_12)) {
usb_stor_transparent_scsi_command(srb, us);
return;
}
memcpy(save_cmnd, srb->cmnd, sizeof(save_cmnd));
memset(srb->cmnd, 0, MAX_COMMAND_SIZE);
/* check if we support the command */
if (save_cmnd[1] >> 5) /* MULTIPLE_COUNT */
goto invalid_fld;
/* check protocol */
switch((save_cmnd[1] >> 1) & 0xf) {
case 3: /*no DATA */
case 4: /* PIO in */
case 5: /* PIO out */
break;
default:
goto invalid_fld;
}
/* first build the ATACB command */
srb->cmd_len = 16;
srb->cmnd[0] = 0x24; /* bVSCBSignature : vendor-specific command
this value can change, but most(all ?) manufacturers
keep the cypress default : 0x24 */
srb->cmnd[1] = 0x24; /* bVSCBSubCommand : 0x24 for ATACB */
srb->cmnd[3] = 0xff - 1; /* features, sector count, lba low, lba med
lba high, device, command are valid */
srb->cmnd[4] = 1; /* TransferBlockCount : 512 */
if (save_cmnd[0] == ATA_16) {
srb->cmnd[ 6] = save_cmnd[ 4]; /* features */
srb->cmnd[ 7] = save_cmnd[ 6]; /* sector count */
srb->cmnd[ 8] = save_cmnd[ 8]; /* lba low */
srb->cmnd[ 9] = save_cmnd[10]; /* lba med */
srb->cmnd[10] = save_cmnd[12]; /* lba high */
srb->cmnd[11] = save_cmnd[13]; /* device */
srb->cmnd[12] = save_cmnd[14]; /* command */
if (save_cmnd[1] & 0x01) {/* extended bit set for LBA48 */
/* this could be supported by atacb2 */
if (save_cmnd[3] || save_cmnd[5] || save_cmnd[7] || save_cmnd[9]
|| save_cmnd[11])
goto invalid_fld;
}
}
else { /* ATA12 */
srb->cmnd[ 6] = save_cmnd[3]; /* features */
srb->cmnd[ 7] = save_cmnd[4]; /* sector count */
srb->cmnd[ 8] = save_cmnd[5]; /* lba low */
srb->cmnd[ 9] = save_cmnd[6]; /* lba med */
srb->cmnd[10] = save_cmnd[7]; /* lba high */
srb->cmnd[11] = save_cmnd[8]; /* device */
srb->cmnd[12] = save_cmnd[9]; /* command */
}
/* Filter SET_FEATURES - XFER MODE command */
if ((srb->cmnd[12] == ATA_CMD_SET_FEATURES)
&& (srb->cmnd[6] == SETFEATURES_XFER))
goto invalid_fld;
if (srb->cmnd[12] == ATA_CMD_ID_ATA || srb->cmnd[12] == ATA_CMD_ID_ATAPI)
srb->cmnd[2] |= (1<<7); /* set IdentifyPacketDevice for these cmds */
usb_stor_transparent_scsi_command(srb, us);
/* if the device doesn't support ATACB
*/
if (srb->result == SAM_STAT_CHECK_CONDITION &&
memcmp(srb->sense_buffer, usb_stor_sense_invalidCDB,
sizeof(usb_stor_sense_invalidCDB)) == 0) {
US_DEBUGP("cypress atacb not supported ???\n");
goto end;
}
/* if ck_cond flags is set, and there wasn't critical error,
* build the special sense
*/
if ((srb->result != (DID_ERROR << 16) &&
srb->result != (DID_ABORT << 16)) &&
save_cmnd[2] & 0x20) {
struct scsi_eh_save ses;
unsigned char regs[8];
unsigned char *sb = srb->sense_buffer;
unsigned char *desc = sb + 8;
int tmp_result;
/* build the command for
* reading the ATA registers */
scsi_eh_prep_cmnd(srb, &ses, NULL, 0, 0);
srb->sdb.length = sizeof(regs);
sg_init_one(&ses.sense_sgl, regs, srb->sdb.length);
srb->sdb.table.sgl = &ses.sense_sgl;
srb->sc_data_direction = DMA_FROM_DEVICE;
srb->sdb.table.nents = 1;
/* we use the same command as before, but we set
* the read taskfile bit, for not executing atacb command,
* but reading register selected in srb->cmnd[4]
*/
srb->cmnd[2] = 1;
usb_stor_transparent_scsi_command(srb, us);
tmp_result = srb->result;
scsi_eh_restore_cmnd(srb, &ses);
/* we fail to get registers, report invalid command */
if (tmp_result != SAM_STAT_GOOD)
goto invalid_fld;
/* build the sense */
memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
/* set sk, asc for a good command */
sb[1] = RECOVERED_ERROR;
sb[2] = 0; /* ATA PASS THROUGH INFORMATION AVAILABLE */
sb[3] = 0x1D;
/* XXX we should generate sk, asc, ascq from status and error
* regs
* (see 11.1 Error translation ATA device error to SCSI error map)
* and ata_to_sense_error from libata.
*/
/* Sense data is current and format is descriptor. */
sb[0] = 0x72;
desc[0] = 0x09; /* ATA_RETURN_DESCRIPTOR */
/* set length of additional sense data */
sb[7] = 14;
desc[1] = 12;
/* Copy registers into sense buffer. */
desc[ 2] = 0x00;
desc[ 3] = regs[1]; /* features */
desc[ 5] = regs[2]; /* sector count */
desc[ 7] = regs[3]; /* lba low */
desc[ 9] = regs[4]; /* lba med */
desc[11] = regs[5]; /* lba high */
desc[12] = regs[6]; /* device */
desc[13] = regs[7]; /* command */
srb->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
}
goto end;
invalid_fld:
srb->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
memcpy(srb->sense_buffer,
usb_stor_sense_invalidCDB,
sizeof(usb_stor_sense_invalidCDB));
end:
memcpy(srb->cmnd, save_cmnd, sizeof(save_cmnd));
if (srb->cmnd[0] == ATA_12)
srb->cmd_len = 12;
}
