LXR linux/drivers/usb/storage/cypress

   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
  33#define DRV_NAME "ums-cypress"
  34
  35MODULE_DESCRIPTION("SAT support for Cypress USB/ATA bridges with ATACB");
  36MODULE_AUTHOR("Matthieu Castet <castet.matthieu@free.fr>");
  37MODULE_LICENSE("GPL");
  38
  39/*
  40 * The table of devices
  41 */
  42#define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
  43                    vendorName, productName, useProtocol, useTransport, \
  44                    initFunction, flags) \
  45{ USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
  46  .driver_info = (flags) }
  47
  48static struct usb_device_id cypress_usb_ids[] = {
  49#       include "unusual_cypress.h"
  50        { }             /* Terminating entry */
  51};
  52MODULE_DEVICE_TABLE(usb, cypress_usb_ids);
  53
  54#undef UNUSUAL_DEV
  55
  56/*
  57 * The flags table
  58 */
  59#define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
  60                    vendor_name, product_name, use_protocol, use_transport, \
  61                    init_function, Flags) \
  62{ \
  63        .vendorName = vendor_name,      \
  64        .productName = product_name,    \
  65        .useProtocol = use_protocol,    \
  66        .useTransport = use_transport,  \
  67        .initFunction = init_function,  \
  68}
  69
  70static struct us_unusual_dev cypress_unusual_dev_list[] = {
  71#       include "unusual_cypress.h"
  72        { }             /* Terminating entry */
  73};
  74
  75#undef UNUSUAL_DEV
  76
  77
  78/*
  79 * ATACB is a protocol used on cypress usb<->ata bridge to
  80 * send raw ATA command over mass storage
  81 * There is a ATACB2 protocol that support LBA48 on newer chip.
  82 * More info that be found on cy7c68310_8.pdf and cy7c68300c_8.pdf
  83 * datasheet from cypress.com.
  84 */
  85static void cypress_atacb_passthrough(struct scsi_cmnd *srb, struct us_data *us)
  86{
  87        unsigned char save_cmnd[MAX_COMMAND_SIZE];
  88
  89        if (likely(srb->cmnd[0] != ATA_16 && srb->cmnd[0] != ATA_12)) {
  90                usb_stor_transparent_scsi_command(srb, us);
  91                return;
  92        }
  93
  94        memcpy(save_cmnd, srb->cmnd, sizeof(save_cmnd));
  95        memset(srb->cmnd, 0, MAX_COMMAND_SIZE);
  96
  97        /* check if we support the command */
  98        if (save_cmnd[1] >> 5) /* MULTIPLE_COUNT */
  99                goto invalid_fld;
 100        /* check protocol */
 101        switch ((save_cmnd[1] >> 1) & 0xf) {
 102        case 3: /*no DATA */
 103        case 4: /* PIO in */
 104        case 5: /* PIO out */
 105                break;
 106        default:
 107                goto invalid_fld;
 108        }
 109
 110        /* first build the ATACB command */
 111        srb->cmd_len = 16;
 112
 113        srb->cmnd[0] = 0x24; /* bVSCBSignature : vendor-specific command
 114                                this value can change, but most(all ?) manufacturers
 115                                                        keep the cypress default : 0x24 */
 116        srb->cmnd[1] = 0x24; /* bVSCBSubCommand : 0x24 for ATACB */
 117
 118        srb->cmnd[3] = 0xff - 1; /* features, sector count, lba low, lba med
 119                                                                lba high, device, command are valid */
 120        srb->cmnd[4] = 1; /* TransferBlockCount : 512 */
 121
 122        if (save_cmnd[0] == ATA_16) {
 123                srb->cmnd[ 6] = save_cmnd[ 4]; /* features */
 124                srb->cmnd[ 7] = save_cmnd[ 6]; /* sector count */
 125                srb->cmnd[ 8] = save_cmnd[ 8]; /* lba low */
 126                srb->cmnd[ 9] = save_cmnd[10]; /* lba med */
 127                srb->cmnd[10] = save_cmnd[12]; /* lba high */
 128                srb->cmnd[11] = save_cmnd[13]; /* device */
 129                srb->cmnd[12] = save_cmnd[14]; /* command */
 130
 131                if (save_cmnd[1] & 0x01) {/* extended bit set for LBA48 */
 132                        /* this could be supported by atacb2 */
 133                        if (save_cmnd[3] || save_cmnd[5] || save_cmnd[7] || save_cmnd[9]
 134                                        || save_cmnd[11])
 135                                goto invalid_fld;
 136                }
 137        } else { /* ATA12 */
 138                srb->cmnd[ 6] = save_cmnd[3]; /* features */
 139                srb->cmnd[ 7] = save_cmnd[4]; /* sector count */
 140                srb->cmnd[ 8] = save_cmnd[5]; /* lba low */
 141                srb->cmnd[ 9] = save_cmnd[6]; /* lba med */
 142                srb->cmnd[10] = save_cmnd[7]; /* lba high */
 143                srb->cmnd[11] = save_cmnd[8]; /* device */
 144                srb->cmnd[12] = save_cmnd[9]; /* command */
 145
 146        }
 147        /* Filter SET_FEATURES - XFER MODE command */
 148        if ((srb->cmnd[12] == ATA_CMD_SET_FEATURES)
 149                        && (srb->cmnd[6] == SETFEATURES_XFER))
 150                goto invalid_fld;
 151
 152        if (srb->cmnd[12] == ATA_CMD_ID_ATA || srb->cmnd[12] == ATA_CMD_ID_ATAPI)
 153                srb->cmnd[2] |= (1<<7); /* set  IdentifyPacketDevice for these cmds */
 154
 155
 156        usb_stor_transparent_scsi_command(srb, us);
 157
 158        /* if the device doesn't support ATACB
 159         */
 160        if (srb->result == SAM_STAT_CHECK_CONDITION &&
 161                        memcmp(srb->sense_buffer, usb_stor_sense_invalidCDB,
 162                                sizeof(usb_stor_sense_invalidCDB)) == 0) {
 163                usb_stor_dbg(us, "cypress atacb not supported ???\n");
 164                goto end;
 165        }
 166
 167        /* if ck_cond flags is set, and there wasn't critical error,
 168         * build the special sense
 169         */
 170        if ((srb->result != (DID_ERROR << 16) &&
 171                                srb->result != (DID_ABORT << 16)) &&
 172                        save_cmnd[2] & 0x20) {
 173                struct scsi_eh_save ses;
 174                unsigned char regs[8];
 175                unsigned char *sb = srb->sense_buffer;
 176                unsigned char *desc = sb + 8;
 177                int tmp_result;
 178
 179                /* build the command for
 180                 * reading the ATA registers */
 181                scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sizeof(regs));
 182
 183                /* we use the same command as before, but we set
 184                 * the read taskfile bit, for not executing atacb command,
 185                 * but reading register selected in srb->cmnd[4]
 186                 */
 187                srb->cmd_len = 16;
 188                srb->cmnd = ses.cmnd;
 189                srb->cmnd[2] = 1;
 190
 191                usb_stor_transparent_scsi_command(srb, us);
 192                memcpy(regs, srb->sense_buffer, sizeof(regs));
 193                tmp_result = srb->result;
 194                scsi_eh_restore_cmnd(srb, &ses);
 195                /* we fail to get registers, report invalid command */
 196                if (tmp_result != SAM_STAT_GOOD)
 197                        goto invalid_fld;
 198
 199                /* build the sense */
 200                memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
 201
 202                /* set sk, asc for a good command */
 203                sb[1] = RECOVERED_ERROR;
 204                sb[2] = 0; /* ATA PASS THROUGH INFORMATION AVAILABLE */
 205                sb[3] = 0x1D;
 206
 207                /* XXX we should generate sk, asc, ascq from status and error
 208                 * regs
 209                 * (see 11.1 Error translation ATA device error to SCSI error
 210                 *  map, and ata_to_sense_error from libata.)
 211                 */
 212
 213                /* Sense data is current and format is descriptor. */
 214                sb[0] = 0x72;
 215                desc[0] = 0x09; /* ATA_RETURN_DESCRIPTOR */
 216
 217                /* set length of additional sense data */
 218                sb[7] = 14;
 219                desc[1] = 12;
 220
 221                /* Copy registers into sense buffer. */
 222                desc[ 2] = 0x00;
 223                desc[ 3] = regs[1];  /* features */
 224                desc[ 5] = regs[2];  /* sector count */
 225                desc[ 7] = regs[3];  /* lba low */
 226                desc[ 9] = regs[4];  /* lba med */
 227                desc[11] = regs[5];  /* lba high */
 228                desc[12] = regs[6];  /* device */
 229                desc[13] = regs[7];  /* command */
 230
 231                srb->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
 232        }
 233        goto end;
 234invalid_fld:
 235        srb->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
 236
 237        memcpy(srb->sense_buffer,
 238                        usb_stor_sense_invalidCDB,
 239                        sizeof(usb_stor_sense_invalidCDB));
 240end:
 241        memcpy(srb->cmnd, save_cmnd, sizeof(save_cmnd));
 242        if (srb->cmnd[0] == ATA_12)
 243                srb->cmd_len = 12;
 244}
 245
 246static struct scsi_host_template cypress_host_template;
 247
 248static int cypress_probe(struct usb_interface *intf,
 249                         const struct usb_device_id *id)
 250{
 251        struct us_data *us;
 252        int result;
 253        struct usb_device *device;
 254
 255        result = usb_stor_probe1(&us, intf, id,
 256                        (id - cypress_usb_ids) + cypress_unusual_dev_list,
 257                        &cypress_host_template);
 258        if (result)
 259                return result;
 260
 261        /* Among CY7C68300 chips, the A revision does not support Cypress ATACB
 262         * Filter out this revision from EEPROM default descriptor values
 263         */
 264        device = interface_to_usbdev(intf);
 265        if (device->descriptor.iManufacturer != 0x38 ||
 266            device->descriptor.iProduct != 0x4e ||
 267            device->descriptor.iSerialNumber != 0x64) {
 268                us->protocol_name = "Transparent SCSI with Cypress ATACB";
 269                us->proto_handler = cypress_atacb_passthrough;
 270        } else {
 271                us->protocol_name = "Transparent SCSI";
 272                us->proto_handler = usb_stor_transparent_scsi_command;
 273        }
 274
 275        result = usb_stor_probe2(us);
 276        return result;
 277}
 278
 279static struct usb_driver cypress_driver = {
 280        .name =         DRV_NAME,
 281        .probe =        cypress_probe,
 282        .disconnect =   usb_stor_disconnect,
 283        .suspend =      usb_stor_suspend,
 284        .resume =       usb_stor_resume,
 285        .reset_resume = usb_stor_reset_resume,
 286        .pre_reset =    usb_stor_pre_reset,
 287        .post_reset =   usb_stor_post_reset,
 288        .id_table =     cypress_usb_ids,
 289        .soft_unbind =  1,
 290        .no_dynamic_id = 1,
 291};
 292
 293module_usb_stor_driver(cypress_driver, cypress_host_template, DRV_NAME);
 294