drivers/usb/storage/cypress_atacb.c

   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
  35 MODULE_DESCRIPTION("SAT support for Cypress USB/ATA bridges with ATACB");
  36 MODULE_AUTHOR("Matthieu Castet <castet.matthieu@free.fr>");
  37 MODULE_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
  48 static struct usb_device_id cypress_usb_ids[] = {
  49 #       include "unusual_cypress.h"
  50         { }             /* Terminating entry */
  51 };
  52 MODULE_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
  70 static 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  */
  85 static 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;
 234 invalid_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));
 240 end:
 241         memcpy(srb->cmnd, save_cmnd, sizeof(save_cmnd));
 242         if (srb->cmnd[0] == ATA_12)
 243                 srb->cmd_len = 12;
 244 }
 245
 246 static struct scsi_host_template cypress_host_template;
 247
 248 static 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
 279 static 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
 293 module_usb_stor_driver(cypress_driver, cypress_host_template, DRV_NAME);