git.oblomov.eu Git - linux-2.6/blob - drivers/ide/ide-atapi.c

   1 /*
   2  * ATAPI support.
   3  */
   4
   5 #include <linux/kernel.h>
   6 #include <linux/delay.h>
   7 #include <linux/ide.h>
   8 #include <scsi/scsi.h>
   9
  10 #ifdef DEBUG
  11 #define debug_log(fmt, args...) \
  12         printk(KERN_INFO "ide: " fmt, ## args)
  13 #else
  14 #define debug_log(fmt, args...) do {} while (0)
  15 #endif
  16
  17 /* TODO: unify the code thus making some arguments go away */
  18 ide_startstop_t ide_pc_intr(ide_drive_t *drive, struct ide_atapi_pc *pc,
  19         ide_handler_t *handler, unsigned int timeout, ide_expiry_t *expiry,
  20         void (*update_buffers)(ide_drive_t *, struct ide_atapi_pc *),
  21         void (*retry_pc)(ide_drive_t *), void (*dsc_handle)(ide_drive_t *),
  22         void (*io_buffers)(ide_drive_t *, struct ide_atapi_pc *, unsigned, int))
  23 {
  24         ide_hwif_t *hwif = drive->hwif;
  25         struct request *rq = hwif->hwgroup->rq;
  26         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
  27         xfer_func_t *xferfunc;
  28         unsigned int temp;
  29         u16 bcount;
  30         u8 stat, ireason, scsi = drive->scsi;
  31
  32         debug_log("Enter %s - interrupt handler\n", __func__);
  33
  34         if (pc->flags & PC_FLAG_TIMEDOUT) {
  35                 drive->pc_callback(drive);
  36                 return ide_stopped;
  37         }
  38
  39         /* Clear the interrupt */
  40         stat = tp_ops->read_status(hwif);
  41
  42         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
  43                 if (hwif->dma_ops->dma_end(drive) ||
  44                     (drive->media == ide_tape && !scsi && (stat & ERR_STAT))) {
  45                         if (drive->media == ide_floppy && !scsi)
  46                                 printk(KERN_ERR "%s: DMA %s error\n",
  47                                         drive->name, rq_data_dir(pc->rq)
  48                                                      ? "write" : "read");
  49                         pc->flags |= PC_FLAG_DMA_ERROR;
  50                 } else {
  51                         pc->xferred = pc->req_xfer;
  52                         if (update_buffers)
  53                                 update_buffers(drive, pc);
  54                 }
  55                 debug_log("%s: DMA finished\n", drive->name);
  56         }
  57
  58         /* No more interrupts */
  59         if ((stat & DRQ_STAT) == 0) {
  60                 debug_log("Packet command completed, %d bytes transferred\n",
  61                           pc->xferred);
  62
  63                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
  64
  65                 local_irq_enable_in_hardirq();
  66
  67                 if (drive->media == ide_tape && !scsi &&
  68                     (stat & ERR_STAT) && rq->cmd[0] == REQUEST_SENSE)
  69                         stat &= ~ERR_STAT;
  70
  71                 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
  72                         /* Error detected */
  73                         debug_log("%s: I/O error\n", drive->name);
  74
  75                         if (drive->media != ide_tape || scsi) {
  76                                 pc->rq->errors++;
  77                                 if (scsi)
  78                                         goto cmd_finished;
  79                         }
  80
  81                         if (rq->cmd[0] == REQUEST_SENSE) {
  82                                 printk(KERN_ERR "%s: I/O error in request sense"
  83                                                 " command\n", drive->name);
  84                                 return ide_do_reset(drive);
  85                         }
  86
  87                         debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
  88
  89                         /* Retry operation */
  90                         retry_pc(drive);
  91
  92                         /* queued, but not started */
  93                         return ide_stopped;
  94                 }
  95 cmd_finished:
  96                 pc->error = 0;
  97                 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
  98                     (stat & SEEK_STAT) == 0) {
  99                         dsc_handle(drive);
 100                         return ide_stopped;
 101                 }
 102
 103                 /* Command finished - Call the callback function */
 104                 drive->pc_callback(drive);
 105
 106                 return ide_stopped;
 107         }
 108
 109         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
 110                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
 111                 printk(KERN_ERR "%s: The device wants to issue more interrupts "
 112                                 "in DMA mode\n", drive->name);
 113                 ide_dma_off(drive);
 114                 return ide_do_reset(drive);
 115         }
 116
 117         /* Get the number of bytes to transfer on this interrupt. */
 118         ide_read_bcount_and_ireason(drive, &bcount, &ireason);
 119
 120         if (ireason & CD) {
 121                 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
 122                 return ide_do_reset(drive);
 123         }
 124
 125         if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
 126                 /* Hopefully, we will never get here */
 127                 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
 128                                 "to %s!\n", drive->name,
 129                                 (ireason & IO) ? "Write" : "Read",
 130                                 (ireason & IO) ? "Read" : "Write");
 131                 return ide_do_reset(drive);
 132         }
 133
 134         if (!(pc->flags & PC_FLAG_WRITING)) {
 135                 /* Reading - Check that we have enough space */
 136                 temp = pc->xferred + bcount;
 137                 if (temp > pc->req_xfer) {
 138                         if (temp > pc->buf_size) {
 139                                 printk(KERN_ERR "%s: The device wants to send "
 140                                                 "us more data than expected - "
 141                                                 "discarding data\n",
 142                                                 drive->name);
 143                                 if (scsi)
 144                                         temp = pc->buf_size - pc->xferred;
 145                                 else
 146                                         temp = 0;
 147                                 if (temp) {
 148                                         if (pc->sg)
 149                                                 io_buffers(drive, pc, temp, 0);
 150                                         else
 151                                                 tp_ops->input_data(drive, NULL,
 152                                                         pc->cur_pos, temp);
 153                                         printk(KERN_ERR "%s: transferred %d of "
 154                                                         "%d bytes\n",
 155                                                         drive->name,
 156                                                         temp, bcount);
 157                                 }
 158                                 pc->xferred += temp;
 159                                 pc->cur_pos += temp;
 160                                 ide_pad_transfer(drive, 0, bcount - temp);
 161                                 ide_set_handler(drive, handler, timeout,
 162                                                 expiry);
 163                                 return ide_started;
 164                         }
 165                         debug_log("The device wants to send us more data than "
 166                                   "expected - allowing transfer\n");
 167                 }
 168                 xferfunc = tp_ops->input_data;
 169         } else
 170                 xferfunc = tp_ops->output_data;
 171
 172         if ((drive->media == ide_floppy && !scsi && !pc->buf) ||
 173             (drive->media == ide_tape && !scsi && pc->bh) ||
 174             (scsi && pc->sg))
 175                 io_buffers(drive, pc, bcount, !!(pc->flags & PC_FLAG_WRITING));
 176         else
 177                 xferfunc(drive, NULL, pc->cur_pos, bcount);
 178
 179         /* Update the current position */
 180         pc->xferred += bcount;
 181         pc->cur_pos += bcount;
 182
 183         debug_log("[cmd %x] transferred %d bytes on that intr.\n",
 184                   rq->cmd[0], bcount);
 185
 186         /* And set the interrupt handler again */
 187         ide_set_handler(drive, handler, timeout, expiry);
 188         return ide_started;
 189 }
 190 EXPORT_SYMBOL_GPL(ide_pc_intr);
 191
 192 static u8 ide_read_ireason(ide_drive_t *drive)
 193 {
 194         ide_task_t task;
 195
 196         memset(&task, 0, sizeof(task));
 197         task.tf_flags = IDE_TFLAG_IN_NSECT;
 198
 199         drive->hwif->tp_ops->tf_read(drive, &task);
 200
 201         return task.tf.nsect & 3;
 202 }
 203
 204 static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
 205 {
 206         int retries = 100;
 207
 208         while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) {
 209                 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
 210                                 "a packet command, retrying\n", drive->name);
 211                 udelay(100);
 212                 ireason = ide_read_ireason(drive);
 213                 if (retries == 0) {
 214                         printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
 215                                         "a packet command, ignoring\n",
 216                                         drive->name);
 217                         ireason |= CD;
 218                         ireason &= ~IO;
 219                 }
 220         }
 221
 222         return ireason;
 223 }
 224
 225 ide_startstop_t ide_transfer_pc(ide_drive_t *drive, struct ide_atapi_pc *pc,
 226                                 ide_handler_t *handler, unsigned int timeout,
 227                                 ide_expiry_t *expiry)
 228 {
 229         ide_hwif_t *hwif = drive->hwif;
 230         struct request *rq = hwif->hwgroup->rq;
 231         ide_startstop_t startstop;
 232         u8 ireason;
 233
 234         if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) {
 235                 printk(KERN_ERR "%s: Strange, packet command initiated yet "
 236                                 "DRQ isn't asserted\n", drive->name);
 237                 return startstop;
 238         }
 239
 240         ireason = ide_read_ireason(drive);
 241         if (drive->media == ide_tape && !drive->scsi)
 242                 ireason = ide_wait_ireason(drive, ireason);
 243
 244         if ((ireason & CD) == 0 || (ireason & IO)) {
 245                 printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
 246                                 "a packet command\n", drive->name);
 247                 return ide_do_reset(drive);
 248         }
 249
 250         /* Set the interrupt routine */
 251         ide_set_handler(drive, handler, timeout, expiry);
 252
 253         /* Begin DMA, if necessary */
 254         if (pc->flags & PC_FLAG_DMA_OK) {
 255                 pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
 256                 hwif->dma_ops->dma_start(drive);
 257         }
 258
 259         /* Send the actual packet */
 260         if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
 261                 hwif->tp_ops->output_data(drive, NULL, rq->cmd, 12);
 262
 263         return ide_started;
 264 }
 265 EXPORT_SYMBOL_GPL(ide_transfer_pc);
 266
 267 ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_atapi_pc *pc,
 268                              ide_handler_t *handler, unsigned int timeout,
 269                              ide_expiry_t *expiry)
 270 {
 271         ide_hwif_t *hwif = drive->hwif;
 272         u16 bcount;
 273         u8 dma = 0;
 274
 275         /* We haven't transferred any data yet */
 276         pc->xferred = 0;
 277         pc->cur_pos = pc->buf;
 278
 279         /* Request to transfer the entire buffer at once */
 280         if (drive->media == ide_tape && !drive->scsi)
 281                 bcount = pc->req_xfer;
 282         else
 283                 bcount = min(pc->req_xfer, 63 * 1024);
 284
 285         if (pc->flags & PC_FLAG_DMA_ERROR) {
 286                 pc->flags &= ~PC_FLAG_DMA_ERROR;
 287                 ide_dma_off(drive);
 288         }
 289
 290         if ((pc->flags & PC_FLAG_DMA_OK) && drive->using_dma) {
 291                 if (drive->scsi)
 292                         hwif->sg_mapped = 1;
 293                 dma = !hwif->dma_ops->dma_setup(drive);
 294                 if (drive->scsi)
 295                         hwif->sg_mapped = 0;
 296         }
 297
 298         if (!dma)
 299                 pc->flags &= ~PC_FLAG_DMA_OK;
 300
 301         ide_pktcmd_tf_load(drive, drive->scsi ? 0 : IDE_TFLAG_OUT_DEVICE,
 302                            bcount, dma);
 303
 304         /* Issue the packet command */
 305         if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
 306                 ide_execute_command(drive, WIN_PACKETCMD, handler,
 307                                     timeout, NULL);
 308                 return ide_started;
 309         } else {
 310                 ide_execute_pkt_cmd(drive);
 311                 return (*handler)(drive);
 312         }
 313 }
 314 EXPORT_SYMBOL_GPL(ide_issue_pc);