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 MODULE_DESCRIPTION("SAT support for Cypress USB/ATA bridges with ATACB");
  34 MODULE_AUTHOR("Matthieu Castet <castet.matthieu@free.fr>");
  35 MODULE_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
  46 struct usb_device_id cypress_usb_ids[] = {
  47 #       include "unusual_cypress.h"
  48         { }             /* Terminating entry */
  49 };
  50 MODULE_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
  68 static 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  */
  83 static 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;
 233 invalid_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));
 239 end:
 240         memcpy(srb->cmnd, save_cmnd, sizeof(save_cmnd));
 241         if (srb->cmnd[0] == ATA_12)
 242                 srb->cmd_len = 12;
 243 }
 244
 245
 246 static 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
 264 static 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
 277 static int __init cypress_init(void)
 278 {
 279         return usb_register(&cypress_driver);
 280 }
 281
 282 static void __exit cypress_exit(void)
 283 {
 284         usb_deregister(&cypress_driver);
 285 }
 286
 287 module_init(cypress_init);
 288 module_exit(cypress_exit);