ide: add ide_queue_pc_head() helper
[linux-2.6.git] / 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 /*
18  * Check whether we can support a device,
19  * based on the ATAPI IDENTIFY command results.
20  */
21 int ide_check_atapi_device(ide_drive_t *drive, const char *s)
22 {
23         u16 *id = drive->id;
24         u8 gcw[2], protocol, device_type, removable, drq_type, packet_size;
25
26         *((u16 *)&gcw) = id[ATA_ID_CONFIG];
27
28         protocol    = (gcw[1] & 0xC0) >> 6;
29         device_type =  gcw[1] & 0x1F;
30         removable   = (gcw[0] & 0x80) >> 7;
31         drq_type    = (gcw[0] & 0x60) >> 5;
32         packet_size =  gcw[0] & 0x03;
33
34 #ifdef CONFIG_PPC
35         /* kludge for Apple PowerBook internal zip */
36         if (drive->media == ide_floppy && device_type == 5 &&
37             !strstr((char *)&id[ATA_ID_PROD], "CD-ROM") &&
38             strstr((char *)&id[ATA_ID_PROD], "ZIP"))
39                 device_type = 0;
40 #endif
41
42         if (protocol != 2)
43                 printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n",
44                         s, drive->name, protocol);
45         else if ((drive->media == ide_floppy && device_type != 0) ||
46                  (drive->media == ide_tape && device_type != 1))
47                 printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n",
48                         s, drive->name, device_type);
49         else if (removable == 0)
50                 printk(KERN_ERR "%s: %s: the removable flag is not set\n",
51                         s, drive->name);
52         else if (drive->media == ide_floppy && drq_type == 3)
53                 printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not "
54                         "supported\n", s, drive->name, drq_type);
55         else if (packet_size != 0)
56                 printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 "
57                         "bytes\n", s, drive->name, packet_size);
58         else
59                 return 1;
60         return 0;
61 }
62 EXPORT_SYMBOL_GPL(ide_check_atapi_device);
63
64 /* PIO data transfer routine using the scatter gather table. */
65 int ide_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
66                     unsigned int bcount, int write)
67 {
68         ide_hwif_t *hwif = drive->hwif;
69         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
70         xfer_func_t *xf = write ? tp_ops->output_data : tp_ops->input_data;
71         struct scatterlist *sg = pc->sg;
72         char *buf;
73         int count, done = 0;
74
75         while (bcount) {
76                 count = min(sg->length - pc->b_count, bcount);
77
78                 if (PageHighMem(sg_page(sg))) {
79                         unsigned long flags;
80
81                         local_irq_save(flags);
82                         buf = kmap_atomic(sg_page(sg), KM_IRQ0) + sg->offset;
83                         xf(drive, NULL, buf + pc->b_count, count);
84                         kunmap_atomic(buf - sg->offset, KM_IRQ0);
85                         local_irq_restore(flags);
86                 } else {
87                         buf = sg_virt(sg);
88                         xf(drive, NULL, buf + pc->b_count, count);
89                 }
90
91                 bcount -= count;
92                 pc->b_count += count;
93                 done += count;
94
95                 if (pc->b_count == sg->length) {
96                         if (!--pc->sg_cnt)
97                                 break;
98                         pc->sg = sg = sg_next(sg);
99                         pc->b_count = 0;
100                 }
101         }
102
103         if (bcount) {
104                 printk(KERN_ERR "%s: %d leftover bytes, %s\n", drive->name,
105                         bcount, write ? "padding with zeros"
106                                       : "discarding data");
107                 ide_pad_transfer(drive, write, bcount);
108         }
109
110         return done;
111 }
112 EXPORT_SYMBOL_GPL(ide_io_buffers);
113
114 void ide_init_pc(struct ide_atapi_pc *pc)
115 {
116         memset(pc, 0, sizeof(*pc));
117         pc->buf = pc->pc_buf;
118         pc->buf_size = IDE_PC_BUFFER_SIZE;
119 }
120 EXPORT_SYMBOL_GPL(ide_init_pc);
121
122 /*
123  * Generate a new packet command request in front of the request queue, before
124  * the current request, so that it will be processed immediately, on the next
125  * pass through the driver.
126  */
127 void ide_queue_pc_head(ide_drive_t *drive, struct gendisk *disk,
128                        struct ide_atapi_pc *pc, struct request *rq)
129 {
130         blk_rq_init(NULL, rq);
131         rq->cmd_type = REQ_TYPE_SPECIAL;
132         rq->cmd_flags |= REQ_PREEMPT;
133         rq->buffer = (char *)pc;
134         rq->rq_disk = disk;
135         memcpy(rq->cmd, pc->c, 12);
136         if (drive->media == ide_tape)
137                 rq->cmd[13] = REQ_IDETAPE_PC1;
138         ide_do_drive_cmd(drive, rq);
139 }
140 EXPORT_SYMBOL_GPL(ide_queue_pc_head);
141
142 /* TODO: unify the code thus making some arguments go away */
143 ide_startstop_t ide_pc_intr(ide_drive_t *drive, struct ide_atapi_pc *pc,
144         ide_handler_t *handler, unsigned int timeout, ide_expiry_t *expiry,
145         void (*update_buffers)(ide_drive_t *, struct ide_atapi_pc *),
146         void (*retry_pc)(ide_drive_t *), void (*dsc_handle)(ide_drive_t *),
147         int (*io_buffers)(ide_drive_t *, struct ide_atapi_pc *, unsigned, int))
148 {
149         ide_hwif_t *hwif = drive->hwif;
150         struct request *rq = hwif->hwgroup->rq;
151         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
152         xfer_func_t *xferfunc;
153         unsigned int temp;
154         u16 bcount;
155         u8 stat, ireason, scsi = drive->scsi;
156
157         debug_log("Enter %s - interrupt handler\n", __func__);
158
159         if (pc->flags & PC_FLAG_TIMEDOUT) {
160                 drive->pc_callback(drive);
161                 return ide_stopped;
162         }
163
164         /* Clear the interrupt */
165         stat = tp_ops->read_status(hwif);
166
167         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
168                 if (hwif->dma_ops->dma_end(drive) ||
169                     (drive->media == ide_tape && !scsi && (stat & ATA_ERR))) {
170                         if (drive->media == ide_floppy && !scsi)
171                                 printk(KERN_ERR "%s: DMA %s error\n",
172                                         drive->name, rq_data_dir(pc->rq)
173                                                      ? "write" : "read");
174                         pc->flags |= PC_FLAG_DMA_ERROR;
175                 } else {
176                         pc->xferred = pc->req_xfer;
177                         if (update_buffers)
178                                 update_buffers(drive, pc);
179                 }
180                 debug_log("%s: DMA finished\n", drive->name);
181         }
182
183         /* No more interrupts */
184         if ((stat & ATA_DRQ) == 0) {
185                 debug_log("Packet command completed, %d bytes transferred\n",
186                           pc->xferred);
187
188                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
189
190                 local_irq_enable_in_hardirq();
191
192                 if (drive->media == ide_tape && !scsi &&
193                     (stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE)
194                         stat &= ~ATA_ERR;
195
196                 if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
197                         /* Error detected */
198                         debug_log("%s: I/O error\n", drive->name);
199
200                         if (drive->media != ide_tape || scsi) {
201                                 pc->rq->errors++;
202                                 if (scsi)
203                                         goto cmd_finished;
204                         }
205
206                         if (rq->cmd[0] == REQUEST_SENSE) {
207                                 printk(KERN_ERR "%s: I/O error in request sense"
208                                                 " command\n", drive->name);
209                                 return ide_do_reset(drive);
210                         }
211
212                         debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
213
214                         /* Retry operation */
215                         retry_pc(drive);
216
217                         /* queued, but not started */
218                         return ide_stopped;
219                 }
220 cmd_finished:
221                 pc->error = 0;
222                 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
223                     (stat & ATA_DSC) == 0) {
224                         dsc_handle(drive);
225                         return ide_stopped;
226                 }
227
228                 /* Command finished - Call the callback function */
229                 drive->pc_callback(drive);
230
231                 return ide_stopped;
232         }
233
234         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
235                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
236                 printk(KERN_ERR "%s: The device wants to issue more interrupts "
237                                 "in DMA mode\n", drive->name);
238                 ide_dma_off(drive);
239                 return ide_do_reset(drive);
240         }
241
242         /* Get the number of bytes to transfer on this interrupt. */
243         ide_read_bcount_and_ireason(drive, &bcount, &ireason);
244
245         if (ireason & ATAPI_COD) {
246                 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
247                 return ide_do_reset(drive);
248         }
249
250         if (((ireason & ATAPI_IO) == ATAPI_IO) ==
251                 !!(pc->flags & PC_FLAG_WRITING)) {
252                 /* Hopefully, we will never get here */
253                 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
254                                 "to %s!\n", drive->name,
255                                 (ireason & ATAPI_IO) ? "Write" : "Read",
256                                 (ireason & ATAPI_IO) ? "Read" : "Write");
257                 return ide_do_reset(drive);
258         }
259
260         if (!(pc->flags & PC_FLAG_WRITING)) {
261                 /* Reading - Check that we have enough space */
262                 temp = pc->xferred + bcount;
263                 if (temp > pc->req_xfer) {
264                         if (temp > pc->buf_size) {
265                                 printk(KERN_ERR "%s: The device wants to send "
266                                                 "us more data than expected - "
267                                                 "discarding data\n",
268                                                 drive->name);
269                                 if (scsi)
270                                         temp = pc->buf_size - pc->xferred;
271                                 else
272                                         temp = 0;
273                                 if (temp) {
274                                         if (pc->sg)
275                                                 io_buffers(drive, pc, temp, 0);
276                                         else
277                                                 tp_ops->input_data(drive, NULL,
278                                                         pc->cur_pos, temp);
279                                         printk(KERN_ERR "%s: transferred %d of "
280                                                         "%d bytes\n",
281                                                         drive->name,
282                                                         temp, bcount);
283                                 }
284                                 pc->xferred += temp;
285                                 pc->cur_pos += temp;
286                                 ide_pad_transfer(drive, 0, bcount - temp);
287                                 ide_set_handler(drive, handler, timeout,
288                                                 expiry);
289                                 return ide_started;
290                         }
291                         debug_log("The device wants to send us more data than "
292                                   "expected - allowing transfer\n");
293                 }
294                 xferfunc = tp_ops->input_data;
295         } else
296                 xferfunc = tp_ops->output_data;
297
298         if ((drive->media == ide_floppy && !scsi && !pc->buf) ||
299             (drive->media == ide_tape && !scsi && pc->bh) ||
300             (scsi && pc->sg)) {
301                 int done = io_buffers(drive, pc, bcount,
302                                   !!(pc->flags & PC_FLAG_WRITING));
303
304                 /* FIXME: don't do partial completions */
305                 if (drive->media == ide_floppy && !scsi)
306                         ide_end_request(drive, 1, done >> 9);
307         } else
308                 xferfunc(drive, NULL, pc->cur_pos, bcount);
309
310         /* Update the current position */
311         pc->xferred += bcount;
312         pc->cur_pos += bcount;
313
314         debug_log("[cmd %x] transferred %d bytes on that intr.\n",
315                   rq->cmd[0], bcount);
316
317         /* And set the interrupt handler again */
318         ide_set_handler(drive, handler, timeout, expiry);
319         return ide_started;
320 }
321 EXPORT_SYMBOL_GPL(ide_pc_intr);
322
323 static u8 ide_read_ireason(ide_drive_t *drive)
324 {
325         ide_task_t task;
326
327         memset(&task, 0, sizeof(task));
328         task.tf_flags = IDE_TFLAG_IN_NSECT;
329
330         drive->hwif->tp_ops->tf_read(drive, &task);
331
332         return task.tf.nsect & 3;
333 }
334
335 static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
336 {
337         int retries = 100;
338
339         while (retries-- && ((ireason & ATAPI_COD) == 0 ||
340                 (ireason & ATAPI_IO))) {
341                 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
342                                 "a packet command, retrying\n", drive->name);
343                 udelay(100);
344                 ireason = ide_read_ireason(drive);
345                 if (retries == 0) {
346                         printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
347                                         "a packet command, ignoring\n",
348                                         drive->name);
349                         ireason |= ATAPI_COD;
350                         ireason &= ~ATAPI_IO;
351                 }
352         }
353
354         return ireason;
355 }
356
357 ide_startstop_t ide_transfer_pc(ide_drive_t *drive, struct ide_atapi_pc *pc,
358                                 ide_handler_t *handler, unsigned int timeout,
359                                 ide_expiry_t *expiry)
360 {
361         ide_hwif_t *hwif = drive->hwif;
362         struct request *rq = hwif->hwgroup->rq;
363         ide_startstop_t startstop;
364         u8 ireason;
365
366         if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
367                 printk(KERN_ERR "%s: Strange, packet command initiated yet "
368                                 "DRQ isn't asserted\n", drive->name);
369                 return startstop;
370         }
371
372         ireason = ide_read_ireason(drive);
373         if (drive->media == ide_tape && !drive->scsi)
374                 ireason = ide_wait_ireason(drive, ireason);
375
376         if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
377                 printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
378                                 "a packet command\n", drive->name);
379                 return ide_do_reset(drive);
380         }
381
382         /* Set the interrupt routine */
383         ide_set_handler(drive, handler, timeout, expiry);
384
385         /* Begin DMA, if necessary */
386         if (pc->flags & PC_FLAG_DMA_OK) {
387                 pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
388                 hwif->dma_ops->dma_start(drive);
389         }
390
391         /* Send the actual packet */
392         if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
393                 hwif->tp_ops->output_data(drive, NULL, rq->cmd, 12);
394
395         return ide_started;
396 }
397 EXPORT_SYMBOL_GPL(ide_transfer_pc);
398
399 ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_atapi_pc *pc,
400                              ide_handler_t *handler, unsigned int timeout,
401                              ide_expiry_t *expiry)
402 {
403         ide_hwif_t *hwif = drive->hwif;
404         u16 bcount;
405         u8 dma = 0;
406
407         /* We haven't transferred any data yet */
408         pc->xferred = 0;
409         pc->cur_pos = pc->buf;
410
411         /* Request to transfer the entire buffer at once */
412         if (drive->media == ide_tape && !drive->scsi)
413                 bcount = pc->req_xfer;
414         else
415                 bcount = min(pc->req_xfer, 63 * 1024);
416
417         if (pc->flags & PC_FLAG_DMA_ERROR) {
418                 pc->flags &= ~PC_FLAG_DMA_ERROR;
419                 ide_dma_off(drive);
420         }
421
422         if ((pc->flags & PC_FLAG_DMA_OK) && drive->using_dma) {
423                 if (drive->scsi)
424                         hwif->sg_mapped = 1;
425                 dma = !hwif->dma_ops->dma_setup(drive);
426                 if (drive->scsi)
427                         hwif->sg_mapped = 0;
428         }
429
430         if (!dma)
431                 pc->flags &= ~PC_FLAG_DMA_OK;
432
433         ide_pktcmd_tf_load(drive, drive->scsi ? 0 : IDE_TFLAG_OUT_DEVICE,
434                            bcount, dma);
435
436         /* Issue the packet command */
437         if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
438                 ide_execute_command(drive, ATA_CMD_PACKET, handler,
439                                     timeout, NULL);
440                 return ide_started;
441         } else {
442                 ide_execute_pkt_cmd(drive);
443                 return (*handler)(drive);
444         }
445 }
446 EXPORT_SYMBOL_GPL(ide_issue_pc);