linux/drivers/usb/storage/cypress_atacb.c
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   1/*
   2 * Support for emulating SAT (ata pass through) on devices based
   3 *       on the Cypress USB/ATA bridge supporting ATACB.
   4 *
   5 * Copyright (c) 2008 Matthieu Castet (castet.matthieu@free.fr)
   6 *
   7 * This program is free software; you can redistribute it and/or modify it
   8 * under the terms of the GNU General Public License as published by the
   9 * Free Software Foundation; either version 2, or (at your option) any
  10 * later version.
  11 *
  12 * This program is distributed in the hope that it will be useful, but
  13 * WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 * General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License along
  18 * with this program; if not, write to the Free Software Foundation, Inc.,
  19 * 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22#include <linux/module.h>
  23#include <scsi/scsi.h>
  24#include <scsi/scsi_cmnd.h>
  25#include <scsi/scsi_eh.h>
  26#include <linux/ata.h>
  27
  28#include "usb.h"
  29#include "protocol.h"
  30#include "scsiglue.h"
  31#include "debug.h"
  32
  33MODULE_DESCRIPTION("SAT support for Cypress USB/ATA bridges with ATACB");
  34MODULE_AUTHOR("Matthieu Castet <castet.matthieu@free.fr>");
  35MODULE_LICENSE("GPL");
  36
  37/*
  38 * The table of devices
  39 */
  40#define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
  41                    vendorName, productName, useProtocol, useTransport, \
  42                    initFunction, flags) \
  43{ USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
  44  .driver_info = (flags)|(USB_US_TYPE_STOR<<24) }
  45
  46struct usb_device_id cypress_usb_ids[] = {
  47#       include "unusual_cypress.h"
  48        { }             /* Terminating entry */
  49};
  50MODULE_DEVICE_TABLE(usb, cypress_usb_ids);
  51
  52#undef UNUSUAL_DEV
  53
  54/*
  55 * The flags table
  56 */
  57#define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
  58                    vendor_name, product_name, use_protocol, use_transport, \
  59                    init_function, Flags) \
  60{ \
  61        .vendorName = vendor_name,      \
  62        .productName = product_name,    \
  63        .useProtocol = use_protocol,    \
  64        .useTransport = use_transport,  \
  65        .initFunction = init_function,  \
  66}
  67
  68static struct us_unusual_dev cypress_unusual_dev_list[] = {
  69#       include "unusual_cypress.h"
  70        { }             /* Terminating entry */
  71};
  72
  73#undef UNUSUAL_DEV
  74
  75
  76/*
  77 * ATACB is a protocol used on cypress usb<->ata bridge to
  78 * send raw ATA command over mass storage
  79 * There is a ATACB2 protocol that support LBA48 on newer chip.
  80 * More info that be found on cy7c68310_8.pdf and cy7c68300c_8.pdf
  81 * datasheet from cypress.com.
  82 */
  83static void cypress_atacb_passthrough(struct scsi_cmnd *srb, struct us_data *us)
  84{
  85        unsigned char save_cmnd[MAX_COMMAND_SIZE];
  86
  87        if (likely(srb->cmnd[0] != ATA_16 && srb->cmnd[0] != ATA_12)) {
  88                usb_stor_transparent_scsi_command(srb, us);
  89                return;
  90        }
  91
  92        memcpy(save_cmnd, srb->cmnd, sizeof(save_cmnd));
  93        memset(srb->cmnd, 0, MAX_COMMAND_SIZE);
  94
  95        /* check if we support the command */
  96        if (save_cmnd[1] >> 5) /* MULTIPLE_COUNT */
  97                goto invalid_fld;
  98        /* check protocol */
  99        switch((save_cmnd[1] >> 1) & 0xf) {
 100                case 3: /*no DATA */
 101                case 4: /* PIO in */
 102                case 5: /* PIO out */
 103                        break;
 104                default:
 105                        goto invalid_fld;
 106        }
 107
 108        /* first build the ATACB command */
 109        srb->cmd_len = 16;
 110
 111        srb->cmnd[0] = 0x24; /* bVSCBSignature : vendor-specific command
 112                                this value can change, but most(all ?) manufacturers
 113                                                        keep the cypress default : 0x24 */
 114        srb->cmnd[1] = 0x24; /* bVSCBSubCommand : 0x24 for ATACB */
 115
 116        srb->cmnd[3] = 0xff - 1; /* features, sector count, lba low, lba med
 117                                                                lba high, device, command are valid */
 118        srb->cmnd[4] = 1; /* TransferBlockCount : 512 */
 119
 120        if (save_cmnd[0] == ATA_16) {
 121                srb->cmnd[ 6] = save_cmnd[ 4]; /* features */
 122                srb->cmnd[ 7] = save_cmnd[ 6]; /* sector count */
 123                srb->cmnd[ 8] = save_cmnd[ 8]; /* lba low */
 124                srb->cmnd[ 9] = save_cmnd[10]; /* lba med */
 125                srb->cmnd[10] = save_cmnd[12]; /* lba high */
 126                srb->cmnd[11] = save_cmnd[13]; /* device */
 127                srb->cmnd[12] = save_cmnd[14]; /* command */
 128
 129                if (save_cmnd[1] & 0x01) {/* extended bit set for LBA48 */
 130                        /* this could be supported by atacb2 */
 131                        if (save_cmnd[3] || save_cmnd[5] || save_cmnd[7] || save_cmnd[9]
 132                                        || save_cmnd[11])
 133                                goto invalid_fld;
 134                }
 135        }
 136        else { /* ATA12 */
 137                srb->cmnd[ 6] = save_cmnd[3]; /* features */
 138                srb->cmnd[ 7] = save_cmnd[4]; /* sector count */
 139                srb->cmnd[ 8] = save_cmnd[5]; /* lba low */
 140                srb->cmnd[ 9] = save_cmnd[6]; /* lba med */
 141                srb->cmnd[10] = save_cmnd[7]; /* lba high */
 142                srb->cmnd[11] = save_cmnd[8]; /* device */
 143                srb->cmnd[12] = save_cmnd[9]; /* command */
 144
 145        }
 146        /* Filter SET_FEATURES - XFER MODE command */
 147        if ((srb->cmnd[12] == ATA_CMD_SET_FEATURES)
 148                        && (srb->cmnd[6] == SETFEATURES_XFER))
 149                goto invalid_fld;
 150
 151        if (srb->cmnd[12] == ATA_CMD_ID_ATA || srb->cmnd[12] == ATA_CMD_ID_ATAPI)
 152                srb->cmnd[2] |= (1<<7); /* set  IdentifyPacketDevice for these cmds */
 153
 154
 155        usb_stor_transparent_scsi_command(srb, us);
 156
 157        /* if the device doesn't support ATACB
 158         */
 159        if (srb->result == SAM_STAT_CHECK_CONDITION &&
 160                        memcmp(srb->sense_buffer, usb_stor_sense_invalidCDB,
 161                                sizeof(usb_stor_sense_invalidCDB)) == 0) {
 162                US_DEBUGP("cypress atacb not supported ???\n");
 163                goto end;
 164        }
 165
 166        /* if ck_cond flags is set, and there wasn't critical error,
 167         * build the special sense
 168         */
 169        if ((srb->result != (DID_ERROR << 16) &&
 170                                srb->result != (DID_ABORT << 16)) &&
 171                        save_cmnd[2] & 0x20) {
 172                struct scsi_eh_save ses;
 173                unsigned char regs[8];
 174                unsigned char *sb = srb->sense_buffer;
 175                unsigned char *desc = sb + 8;
 176                int tmp_result;
 177
 178                /* build the command for
 179                 * reading the ATA registers */
 180                scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sizeof(regs));
 181
 182                /* we use the same command as before, but we set
 183                 * the read taskfile bit, for not executing atacb command,
 184                 * but reading register selected in srb->cmnd[4]
 185                 */
 186                srb->cmd_len = 16;
 187                srb->cmnd = ses.cmnd;
 188                srb->cmnd[2] = 1;
 189
 190                usb_stor_transparent_scsi_command(srb, us);
 191                memcpy(regs, srb->sense_buffer, sizeof(regs));
 192                tmp_result = srb->result;
 193                scsi_eh_restore_cmnd(srb, &ses);
 194                /* we fail to get registers, report invalid command */
 195                if (tmp_result != SAM_STAT_GOOD)
 196                        goto invalid_fld;
 197
 198                /* build the sense */
 199                memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
 200
 201                /* set sk, asc for a good command */
 202                sb[1] = RECOVERED_ERROR;
 203                sb[2] = 0; /* ATA PASS THROUGH INFORMATION AVAILABLE */
 204                sb[3] = 0x1D;
 205
 206                /* XXX we should generate sk, asc, ascq from status and error
 207                 * regs
 208                 * (see 11.1 Error translation ATA device error to SCSI error
 209                 *  map, and ata_to_sense_error from libata.)
 210                 */
 211
 212                /* Sense data is current and format is descriptor. */
 213                sb[0] = 0x72;
 214                desc[0] = 0x09; /* ATA_RETURN_DESCRIPTOR */
 215
 216                /* set length of additional sense data */
 217                sb[7] = 14;
 218                desc[1] = 12;
 219
 220                /* Copy registers into sense buffer. */
 221                desc[ 2] = 0x00;
 222                desc[ 3] = regs[1];  /* features */
 223                desc[ 5] = regs[2];  /* sector count */
 224                desc[ 7] = regs[3];  /* lba low */
 225                desc[ 9] = regs[4];  /* lba med */
 226                desc[11] = regs[5];  /* lba high */
 227                desc[12] = regs[6];  /* device */
 228                desc[13] = regs[7];  /* command */
 229
 230                srb->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
 231        }
 232        goto end;
 233invalid_fld:
 234        srb->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
 235
 236        memcpy(srb->sense_buffer,
 237                        usb_stor_sense_invalidCDB,
 238                        sizeof(usb_stor_sense_invalidCDB));
 239end:
 240        memcpy(srb->cmnd, save_cmnd, sizeof(save_cmnd));
 241        if (srb->cmnd[0] == ATA_12)
 242                srb->cmd_len = 12;
 243}
 244
 245
 246static int cypress_probe(struct usb_interface *intf,
 247                         const struct usb_device_id *id)
 248{
 249        struct us_data *us;
 250        int result;
 251
 252        result = usb_stor_probe1(&us, intf, id,
 253                        (id - cypress_usb_ids) + cypress_unusual_dev_list);
 254        if (result)
 255                return result;
 256
 257        us->protocol_name = "Transparent SCSI with Cypress ATACB";
 258        us->proto_handler = cypress_atacb_passthrough;
 259
 260        result = usb_stor_probe2(us);
 261        return result;
 262}
 263
 264static struct usb_driver cypress_driver = {
 265        .name =         "ums-cypress",
 266        .probe =        cypress_probe,
 267        .disconnect =   usb_stor_disconnect,
 268        .suspend =      usb_stor_suspend,
 269        .resume =       usb_stor_resume,
 270        .reset_resume = usb_stor_reset_resume,
 271        .pre_reset =    usb_stor_pre_reset,
 272        .post_reset =   usb_stor_post_reset,
 273        .id_table =     cypress_usb_ids,
 274        .soft_unbind =  1,
 275};
 276
 277static int __init cypress_init(void)
 278{
 279        return usb_register(&cypress_driver);
 280}
 281
 282static void __exit cypress_exit(void)
 283{
 284        usb_deregister(&cypress_driver);
 285}
 286
 287module_init(cypress_init);
 288module_exit(cypress_exit);
 289