4 * Basic PIO and command management functionality.
6 * This code was split off from ide.c. See ide.c for history and original
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2, or (at your option) any
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * For the avoidance of doubt the "preferred form" of this code is one which
20 * is in an open non patent encumbered format. Where cryptographic key signing
21 * forms part of the process of creating an executable the information
22 * including keys needed to generate an equivalently functional executable
23 * are deemed to be part of the source code.
27 #include <linux/module.h>
28 #include <linux/types.h>
29 #include <linux/string.h>
30 #include <linux/kernel.h>
31 #include <linux/timer.h>
33 #include <linux/interrupt.h>
34 #include <linux/major.h>
35 #include <linux/errno.h>
36 #include <linux/genhd.h>
37 #include <linux/blkpg.h>
38 #include <linux/slab.h>
39 #include <linux/init.h>
40 #include <linux/pci.h>
41 #include <linux/delay.h>
42 #include <linux/ide.h>
43 #include <linux/completion.h>
44 #include <linux/reboot.h>
45 #include <linux/cdrom.h>
46 #include <linux/seq_file.h>
47 #include <linux/device.h>
48 #include <linux/kmod.h>
49 #include <linux/scatterlist.h>
50 #include <linux/bitops.h>
52 #include <asm/byteorder.h>
54 #include <asm/uaccess.h>
57 int ide_end_rq(ide_drive_t
*drive
, struct request
*rq
, int error
,
58 unsigned int nr_bytes
)
61 * decide whether to reenable DMA -- 3 is a random magic for now,
62 * if we DMA timeout more than 3 times, just stay in PIO
64 if ((drive
->dev_flags
& IDE_DFLAG_DMA_PIO_RETRY
) &&
65 drive
->retry_pio
<= 3) {
66 drive
->dev_flags
&= ~IDE_DFLAG_DMA_PIO_RETRY
;
70 return blk_end_request(rq
, error
, nr_bytes
);
72 EXPORT_SYMBOL_GPL(ide_end_rq
);
74 void ide_complete_cmd(ide_drive_t
*drive
, struct ide_cmd
*cmd
, u8 stat
, u8 err
)
76 const struct ide_tp_ops
*tp_ops
= drive
->hwif
->tp_ops
;
77 struct ide_taskfile
*tf
= &cmd
->tf
;
78 struct request
*rq
= cmd
->rq
;
79 u8 tf_cmd
= tf
->command
;
84 if (cmd
->ftf_flags
& IDE_FTFLAG_IN_DATA
) {
87 tp_ops
->input_data(drive
, cmd
, data
, 2);
89 cmd
->tf
.data
= data
[0];
90 cmd
->hob
.data
= data
[1];
93 ide_tf_readback(drive
, cmd
);
95 if ((cmd
->tf_flags
& IDE_TFLAG_CUSTOM_HANDLER
) &&
96 tf_cmd
== ATA_CMD_IDLEIMMEDIATE
) {
97 if (tf
->lbal
!= 0xc4) {
98 printk(KERN_ERR
"%s: head unload failed!\n",
100 ide_tf_dump(drive
->name
, cmd
);
102 drive
->dev_flags
|= IDE_DFLAG_PARKED
;
105 if (rq
&& rq
->cmd_type
== REQ_TYPE_ATA_TASKFILE
) {
106 struct ide_cmd
*orig_cmd
= rq
->special
;
108 if (cmd
->tf_flags
& IDE_TFLAG_DYN
)
111 memcpy(orig_cmd
, cmd
, sizeof(*cmd
));
115 /* obsolete, blk_rq_bytes() should be used instead */
116 unsigned int ide_rq_bytes(struct request
*rq
)
118 if (blk_pc_request(rq
))
121 return rq
->hard_cur_sectors
<< 9;
123 EXPORT_SYMBOL_GPL(ide_rq_bytes
);
125 int ide_complete_rq(ide_drive_t
*drive
, int error
, unsigned int nr_bytes
)
127 ide_hwif_t
*hwif
= drive
->hwif
;
128 struct request
*rq
= hwif
->rq
;
132 * if failfast is set on a request, override number of sectors
133 * and complete the whole request right now
135 if (blk_noretry_request(rq
) && error
<= 0)
136 nr_bytes
= rq
->hard_nr_sectors
<< 9;
138 rc
= ide_end_rq(drive
, rq
, error
, nr_bytes
);
144 EXPORT_SYMBOL(ide_complete_rq
);
146 void ide_kill_rq(ide_drive_t
*drive
, struct request
*rq
)
148 u8 drv_req
= blk_special_request(rq
) && rq
->rq_disk
;
149 u8 media
= drive
->media
;
151 drive
->failed_pc
= NULL
;
153 if ((media
== ide_floppy
|| media
== ide_tape
) && drv_req
) {
155 ide_complete_rq(drive
, 0, blk_rq_bytes(rq
));
157 if (media
== ide_tape
)
158 rq
->errors
= IDE_DRV_ERROR_GENERAL
;
159 else if (blk_fs_request(rq
) == 0 && rq
->errors
== 0)
161 ide_complete_rq(drive
, -EIO
, ide_rq_bytes(rq
));
165 static void ide_tf_set_specify_cmd(ide_drive_t
*drive
, struct ide_taskfile
*tf
)
167 tf
->nsect
= drive
->sect
;
168 tf
->lbal
= drive
->sect
;
169 tf
->lbam
= drive
->cyl
;
170 tf
->lbah
= drive
->cyl
>> 8;
171 tf
->device
= (drive
->head
- 1) | drive
->select
;
172 tf
->command
= ATA_CMD_INIT_DEV_PARAMS
;
175 static void ide_tf_set_restore_cmd(ide_drive_t
*drive
, struct ide_taskfile
*tf
)
177 tf
->nsect
= drive
->sect
;
178 tf
->command
= ATA_CMD_RESTORE
;
181 static void ide_tf_set_setmult_cmd(ide_drive_t
*drive
, struct ide_taskfile
*tf
)
183 tf
->nsect
= drive
->mult_req
;
184 tf
->command
= ATA_CMD_SET_MULTI
;
188 * do_special - issue some special commands
189 * @drive: drive the command is for
191 * do_special() is used to issue ATA_CMD_INIT_DEV_PARAMS,
192 * ATA_CMD_RESTORE and ATA_CMD_SET_MULTI commands to a drive.
195 static ide_startstop_t
do_special(ide_drive_t
*drive
)
200 printk(KERN_DEBUG
"%s: %s: 0x%02x\n", drive
->name
, __func__
,
201 drive
->special_flags
);
203 if (drive
->media
!= ide_disk
) {
204 drive
->special_flags
= 0;
209 memset(&cmd
, 0, sizeof(cmd
));
210 cmd
.protocol
= ATA_PROT_NODATA
;
212 if (drive
->special_flags
& IDE_SFLAG_SET_GEOMETRY
) {
213 drive
->special_flags
&= ~IDE_SFLAG_SET_GEOMETRY
;
214 ide_tf_set_specify_cmd(drive
, &cmd
.tf
);
215 } else if (drive
->special_flags
& IDE_SFLAG_RECALIBRATE
) {
216 drive
->special_flags
&= ~IDE_SFLAG_RECALIBRATE
;
217 ide_tf_set_restore_cmd(drive
, &cmd
.tf
);
218 } else if (drive
->special_flags
& IDE_SFLAG_SET_MULTMODE
) {
219 drive
->special_flags
&= ~IDE_SFLAG_SET_MULTMODE
;
220 ide_tf_set_setmult_cmd(drive
, &cmd
.tf
);
224 cmd
.valid
.out
.tf
= IDE_VALID_OUT_TF
| IDE_VALID_DEVICE
;
225 cmd
.valid
.in
.tf
= IDE_VALID_IN_TF
| IDE_VALID_DEVICE
;
226 cmd
.tf_flags
= IDE_TFLAG_CUSTOM_HANDLER
;
228 do_rw_taskfile(drive
, &cmd
);
233 void ide_map_sg(ide_drive_t
*drive
, struct ide_cmd
*cmd
)
235 ide_hwif_t
*hwif
= drive
->hwif
;
236 struct scatterlist
*sg
= hwif
->sg_table
;
237 struct request
*rq
= cmd
->rq
;
239 cmd
->sg_nents
= blk_rq_map_sg(drive
->queue
, rq
, sg
);
241 EXPORT_SYMBOL_GPL(ide_map_sg
);
243 void ide_init_sg_cmd(struct ide_cmd
*cmd
, unsigned int nr_bytes
)
245 cmd
->nbytes
= cmd
->nleft
= nr_bytes
;
249 EXPORT_SYMBOL_GPL(ide_init_sg_cmd
);
252 * execute_drive_command - issue special drive command
253 * @drive: the drive to issue the command on
254 * @rq: the request structure holding the command
256 * execute_drive_cmd() issues a special drive command, usually
257 * initiated by ioctl() from the external hdparm program. The
258 * command can be a drive command, drive task or taskfile
259 * operation. Weirdly you can call it with NULL to wait for
260 * all commands to finish. Don't do this as that is due to change
263 static ide_startstop_t
execute_drive_cmd (ide_drive_t
*drive
,
266 struct ide_cmd
*cmd
= rq
->special
;
269 if (cmd
->protocol
== ATA_PROT_PIO
) {
270 ide_init_sg_cmd(cmd
, rq
->nr_sectors
<< 9);
271 ide_map_sg(drive
, cmd
);
274 return do_rw_taskfile(drive
, cmd
);
278 * NULL is actually a valid way of waiting for
279 * all current requests to be flushed from the queue.
282 printk("%s: DRIVE_CMD (null)\n", drive
->name
);
285 ide_complete_rq(drive
, 0, blk_rq_bytes(rq
));
290 static ide_startstop_t
ide_special_rq(ide_drive_t
*drive
, struct request
*rq
)
296 case REQ_UNPARK_HEADS
:
297 return ide_do_park_unpark(drive
, rq
);
298 case REQ_DEVSET_EXEC
:
299 return ide_do_devset(drive
, rq
);
300 case REQ_DRIVE_RESET
:
301 return ide_do_reset(drive
);
308 * start_request - start of I/O and command issuing for IDE
310 * start_request() initiates handling of a new I/O request. It
311 * accepts commands and I/O (read/write) requests.
313 * FIXME: this function needs a rename
316 static ide_startstop_t
start_request (ide_drive_t
*drive
, struct request
*rq
)
318 ide_startstop_t startstop
;
320 BUG_ON(!blk_rq_started(rq
));
323 printk("%s: start_request: current=0x%08lx\n",
324 drive
->hwif
->name
, (unsigned long) rq
);
327 /* bail early if we've exceeded max_failures */
328 if (drive
->max_failures
&& (drive
->failures
> drive
->max_failures
)) {
329 rq
->cmd_flags
|= REQ_FAILED
;
333 if (blk_pm_request(rq
))
334 ide_check_pm_state(drive
, rq
);
336 drive
->hwif
->tp_ops
->dev_select(drive
);
337 if (ide_wait_stat(&startstop
, drive
, drive
->ready_stat
,
338 ATA_BUSY
| ATA_DRQ
, WAIT_READY
)) {
339 printk(KERN_ERR
"%s: drive not ready for command\n", drive
->name
);
343 if (drive
->special_flags
== 0) {
344 struct ide_driver
*drv
;
347 * We reset the drive so we need to issue a SETFEATURES.
348 * Do it _after_ do_special() restored device parameters.
350 if (drive
->current_speed
== 0xff)
351 ide_config_drive_speed(drive
, drive
->desired_speed
);
353 if (rq
->cmd_type
== REQ_TYPE_ATA_TASKFILE
)
354 return execute_drive_cmd(drive
, rq
);
355 else if (blk_pm_request(rq
)) {
356 struct request_pm_state
*pm
= rq
->special
;
358 printk("%s: start_power_step(step: %d)\n",
359 drive
->name
, pm
->pm_step
);
361 startstop
= ide_start_power_step(drive
, rq
);
362 if (startstop
== ide_stopped
&&
363 pm
->pm_step
== IDE_PM_COMPLETED
)
364 ide_complete_pm_rq(drive
, rq
);
366 } else if (!rq
->rq_disk
&& blk_special_request(rq
))
368 * TODO: Once all ULDs have been modified to
369 * check for specific op codes rather than
370 * blindly accepting any special request, the
371 * check for ->rq_disk above may be replaced
372 * by a more suitable mechanism or even
375 return ide_special_rq(drive
, rq
);
377 drv
= *(struct ide_driver
**)rq
->rq_disk
->private_data
;
379 return drv
->do_request(drive
, rq
, rq
->sector
);
381 return do_special(drive
);
383 ide_kill_rq(drive
, rq
);
388 * ide_stall_queue - pause an IDE device
389 * @drive: drive to stall
390 * @timeout: time to stall for (jiffies)
392 * ide_stall_queue() can be used by a drive to give excess bandwidth back
393 * to the port by sleeping for timeout jiffies.
396 void ide_stall_queue (ide_drive_t
*drive
, unsigned long timeout
)
398 if (timeout
> WAIT_WORSTCASE
)
399 timeout
= WAIT_WORSTCASE
;
400 drive
->sleep
= timeout
+ jiffies
;
401 drive
->dev_flags
|= IDE_DFLAG_SLEEPING
;
403 EXPORT_SYMBOL(ide_stall_queue
);
405 static inline int ide_lock_port(ide_hwif_t
*hwif
)
415 static inline void ide_unlock_port(ide_hwif_t
*hwif
)
420 static inline int ide_lock_host(struct ide_host
*host
, ide_hwif_t
*hwif
)
424 if (host
->host_flags
& IDE_HFLAG_SERIALIZE
) {
425 rc
= test_and_set_bit_lock(IDE_HOST_BUSY
, &host
->host_busy
);
428 host
->get_lock(ide_intr
, hwif
);
434 static inline void ide_unlock_host(struct ide_host
*host
)
436 if (host
->host_flags
& IDE_HFLAG_SERIALIZE
) {
437 if (host
->release_lock
)
438 host
->release_lock();
439 clear_bit_unlock(IDE_HOST_BUSY
, &host
->host_busy
);
444 * Issue a new request to a device.
446 void do_ide_request(struct request_queue
*q
)
448 ide_drive_t
*drive
= q
->queuedata
;
449 ide_hwif_t
*hwif
= drive
->hwif
;
450 struct ide_host
*host
= hwif
->host
;
451 struct request
*rq
= NULL
;
452 ide_startstop_t startstop
;
455 * drive is doing pre-flush, ordered write, post-flush sequence. even
456 * though that is 3 requests, it must be seen as a single transaction.
457 * we must not preempt this drive until that is complete
459 if (blk_queue_flushing(q
))
461 * small race where queue could get replugged during
462 * the 3-request flush cycle, just yank the plug since
463 * we want it to finish asap
467 spin_unlock_irq(q
->queue_lock
);
469 /* HLD do_request() callback might sleep, make sure it's okay */
472 if (ide_lock_host(host
, hwif
))
475 spin_lock_irq(&hwif
->lock
);
477 if (!ide_lock_port(hwif
)) {
478 ide_hwif_t
*prev_port
;
480 prev_port
= hwif
->host
->cur_port
;
483 if (drive
->dev_flags
& IDE_DFLAG_SLEEPING
&&
484 time_after(drive
->sleep
, jiffies
)) {
485 ide_unlock_port(hwif
);
489 if ((hwif
->host
->host_flags
& IDE_HFLAG_SERIALIZE
) &&
491 ide_drive_t
*cur_dev
=
492 prev_port
? prev_port
->cur_dev
: NULL
;
495 * set nIEN for previous port, drives in the
496 * quirk list may not like intr setups/cleanups
499 (cur_dev
->dev_flags
& IDE_DFLAG_NIEN_QUIRK
) == 0)
500 prev_port
->tp_ops
->write_devctl(prev_port
,
504 hwif
->host
->cur_port
= hwif
;
506 hwif
->cur_dev
= drive
;
507 drive
->dev_flags
&= ~(IDE_DFLAG_SLEEPING
| IDE_DFLAG_PARKED
);
509 spin_unlock_irq(&hwif
->lock
);
510 spin_lock_irq(q
->queue_lock
);
512 * we know that the queue isn't empty, but this can happen
513 * if the q->prep_rq_fn() decides to kill a request
515 rq
= elv_next_request(drive
->queue
);
516 spin_unlock_irq(q
->queue_lock
);
517 spin_lock_irq(&hwif
->lock
);
520 ide_unlock_port(hwif
);
525 * Sanity: don't accept a request that isn't a PM request
526 * if we are currently power managed. This is very important as
527 * blk_stop_queue() doesn't prevent the elv_next_request()
528 * above to return us whatever is in the queue. Since we call
529 * ide_do_request() ourselves, we end up taking requests while
530 * the queue is blocked...
532 * We let requests forced at head of queue with ide-preempt
533 * though. I hope that doesn't happen too much, hopefully not
534 * unless the subdriver triggers such a thing in its own PM
537 if ((drive
->dev_flags
& IDE_DFLAG_BLOCKED
) &&
538 blk_pm_request(rq
) == 0 &&
539 (rq
->cmd_flags
& REQ_PREEMPT
) == 0) {
540 /* there should be no pending command at this point */
541 ide_unlock_port(hwif
);
547 spin_unlock_irq(&hwif
->lock
);
548 startstop
= start_request(drive
, rq
);
549 spin_lock_irq(&hwif
->lock
);
551 if (startstop
== ide_stopped
)
556 spin_unlock_irq(&hwif
->lock
);
558 ide_unlock_host(host
);
559 spin_lock_irq(q
->queue_lock
);
563 spin_unlock_irq(&hwif
->lock
);
564 ide_unlock_host(host
);
566 spin_lock_irq(q
->queue_lock
);
568 if (!elv_queue_empty(q
))
572 static void ide_plug_device(ide_drive_t
*drive
)
574 struct request_queue
*q
= drive
->queue
;
577 spin_lock_irqsave(q
->queue_lock
, flags
);
578 if (!elv_queue_empty(q
))
580 spin_unlock_irqrestore(q
->queue_lock
, flags
);
583 static int drive_is_ready(ide_drive_t
*drive
)
585 ide_hwif_t
*hwif
= drive
->hwif
;
588 if (drive
->waiting_for_dma
)
589 return hwif
->dma_ops
->dma_test_irq(drive
);
591 if (hwif
->io_ports
.ctl_addr
&&
592 (hwif
->host_flags
& IDE_HFLAG_BROKEN_ALTSTATUS
) == 0)
593 stat
= hwif
->tp_ops
->read_altstatus(hwif
);
595 /* Note: this may clear a pending IRQ!! */
596 stat
= hwif
->tp_ops
->read_status(hwif
);
599 /* drive busy: definitely not interrupting */
602 /* drive ready: *might* be interrupting */
607 * ide_timer_expiry - handle lack of an IDE interrupt
608 * @data: timer callback magic (hwif)
610 * An IDE command has timed out before the expected drive return
611 * occurred. At this point we attempt to clean up the current
612 * mess. If the current handler includes an expiry handler then
613 * we invoke the expiry handler, and providing it is happy the
614 * work is done. If that fails we apply generic recovery rules
615 * invoking the handler and checking the drive DMA status. We
616 * have an excessively incestuous relationship with the DMA
617 * logic that wants cleaning up.
620 void ide_timer_expiry (unsigned long data
)
622 ide_hwif_t
*hwif
= (ide_hwif_t
*)data
;
623 ide_drive_t
*uninitialized_var(drive
);
624 ide_handler_t
*handler
;
629 spin_lock_irqsave(&hwif
->lock
, flags
);
631 handler
= hwif
->handler
;
633 if (handler
== NULL
|| hwif
->req_gen
!= hwif
->req_gen_timer
) {
635 * Either a marginal timeout occurred
636 * (got the interrupt just as timer expired),
637 * or we were "sleeping" to give other devices a chance.
638 * Either way, we don't really want to complain about anything.
641 ide_expiry_t
*expiry
= hwif
->expiry
;
642 ide_startstop_t startstop
= ide_stopped
;
644 drive
= hwif
->cur_dev
;
647 wait
= expiry(drive
);
648 if (wait
> 0) { /* continue */
650 hwif
->timer
.expires
= jiffies
+ wait
;
651 hwif
->req_gen_timer
= hwif
->req_gen
;
652 add_timer(&hwif
->timer
);
653 spin_unlock_irqrestore(&hwif
->lock
, flags
);
657 hwif
->handler
= NULL
;
660 * We need to simulate a real interrupt when invoking
661 * the handler() function, which means we need to
662 * globally mask the specific IRQ:
664 spin_unlock(&hwif
->lock
);
665 /* disable_irq_nosync ?? */
666 disable_irq(hwif
->irq
);
667 /* local CPU only, as if we were handling an interrupt */
670 startstop
= handler(drive
);
671 } else if (drive_is_ready(drive
)) {
672 if (drive
->waiting_for_dma
)
673 hwif
->dma_ops
->dma_lost_irq(drive
);
675 hwif
->ack_intr(hwif
);
676 printk(KERN_WARNING
"%s: lost interrupt\n",
678 startstop
= handler(drive
);
680 if (drive
->waiting_for_dma
)
681 startstop
= ide_dma_timeout_retry(drive
, wait
);
683 startstop
= ide_error(drive
, "irq timeout",
684 hwif
->tp_ops
->read_status(hwif
));
686 spin_lock_irq(&hwif
->lock
);
687 enable_irq(hwif
->irq
);
688 if (startstop
== ide_stopped
&& hwif
->polling
== 0) {
689 ide_unlock_port(hwif
);
693 spin_unlock_irqrestore(&hwif
->lock
, flags
);
696 ide_unlock_host(hwif
->host
);
697 ide_plug_device(drive
);
702 * unexpected_intr - handle an unexpected IDE interrupt
703 * @irq: interrupt line
704 * @hwif: port being processed
706 * There's nothing really useful we can do with an unexpected interrupt,
707 * other than reading the status register (to clear it), and logging it.
708 * There should be no way that an irq can happen before we're ready for it,
709 * so we needn't worry much about losing an "important" interrupt here.
711 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
712 * the drive enters "idle", "standby", or "sleep" mode, so if the status
713 * looks "good", we just ignore the interrupt completely.
715 * This routine assumes __cli() is in effect when called.
717 * If an unexpected interrupt happens on irq15 while we are handling irq14
718 * and if the two interfaces are "serialized" (CMD640), then it looks like
719 * we could screw up by interfering with a new request being set up for
722 * In reality, this is a non-issue. The new command is not sent unless
723 * the drive is ready to accept one, in which case we know the drive is
724 * not trying to interrupt us. And ide_set_handler() is always invoked
725 * before completing the issuance of any new drive command, so we will not
726 * be accidentally invoked as a result of any valid command completion
730 static void unexpected_intr(int irq
, ide_hwif_t
*hwif
)
732 u8 stat
= hwif
->tp_ops
->read_status(hwif
);
734 if (!OK_STAT(stat
, ATA_DRDY
, BAD_STAT
)) {
735 /* Try to not flood the console with msgs */
736 static unsigned long last_msgtime
, count
;
739 if (time_after(jiffies
, last_msgtime
+ HZ
)) {
740 last_msgtime
= jiffies
;
741 printk(KERN_ERR
"%s: unexpected interrupt, "
742 "status=0x%02x, count=%ld\n",
743 hwif
->name
, stat
, count
);
749 * ide_intr - default IDE interrupt handler
750 * @irq: interrupt number
752 * @regs: unused weirdness from the kernel irq layer
754 * This is the default IRQ handler for the IDE layer. You should
755 * not need to override it. If you do be aware it is subtle in
758 * hwif is the interface in the group currently performing
759 * a command. hwif->cur_dev is the drive and hwif->handler is
760 * the IRQ handler to call. As we issue a command the handlers
761 * step through multiple states, reassigning the handler to the
762 * next step in the process. Unlike a smart SCSI controller IDE
763 * expects the main processor to sequence the various transfer
764 * stages. We also manage a poll timer to catch up with most
765 * timeout situations. There are still a few where the handlers
766 * don't ever decide to give up.
768 * The handler eventually returns ide_stopped to indicate the
769 * request completed. At this point we issue the next request
770 * on the port and the process begins again.
773 irqreturn_t
ide_intr (int irq
, void *dev_id
)
775 ide_hwif_t
*hwif
= (ide_hwif_t
*)dev_id
;
776 struct ide_host
*host
= hwif
->host
;
777 ide_drive_t
*uninitialized_var(drive
);
778 ide_handler_t
*handler
;
780 ide_startstop_t startstop
;
781 irqreturn_t irq_ret
= IRQ_NONE
;
784 if (host
->host_flags
& IDE_HFLAG_SERIALIZE
) {
785 if (hwif
!= host
->cur_port
)
789 spin_lock_irqsave(&hwif
->lock
, flags
);
791 if (hwif
->ack_intr
&& hwif
->ack_intr(hwif
) == 0)
794 handler
= hwif
->handler
;
796 if (handler
== NULL
|| hwif
->polling
) {
798 * Not expecting an interrupt from this drive.
799 * That means this could be:
800 * (1) an interrupt from another PCI device
801 * sharing the same PCI INT# as us.
802 * or (2) a drive just entered sleep or standby mode,
803 * and is interrupting to let us know.
804 * or (3) a spurious interrupt of unknown origin.
806 * For PCI, we cannot tell the difference,
807 * so in that case we just ignore it and hope it goes away.
809 if ((host
->irq_flags
& IRQF_SHARED
) == 0) {
811 * Probably not a shared PCI interrupt,
812 * so we can safely try to do something about it:
814 unexpected_intr(irq
, hwif
);
817 * Whack the status register, just in case
818 * we have a leftover pending IRQ.
820 (void)hwif
->tp_ops
->read_status(hwif
);
825 drive
= hwif
->cur_dev
;
827 if (!drive_is_ready(drive
))
829 * This happens regularly when we share a PCI IRQ with
830 * another device. Unfortunately, it can also happen
831 * with some buggy drives that trigger the IRQ before
832 * their status register is up to date. Hopefully we have
833 * enough advance overhead that the latter isn't a problem.
837 hwif
->handler
= NULL
;
840 del_timer(&hwif
->timer
);
841 spin_unlock(&hwif
->lock
);
843 if (hwif
->port_ops
&& hwif
->port_ops
->clear_irq
)
844 hwif
->port_ops
->clear_irq(drive
);
846 if (drive
->dev_flags
& IDE_DFLAG_UNMASK
)
847 local_irq_enable_in_hardirq();
849 /* service this interrupt, may set handler for next interrupt */
850 startstop
= handler(drive
);
852 spin_lock_irq(&hwif
->lock
);
854 * Note that handler() may have set things up for another
855 * interrupt to occur soon, but it cannot happen until
856 * we exit from this routine, because it will be the
857 * same irq as is currently being serviced here, and Linux
858 * won't allow another of the same (on any CPU) until we return.
860 if (startstop
== ide_stopped
&& hwif
->polling
== 0) {
861 BUG_ON(hwif
->handler
);
862 ide_unlock_port(hwif
);
865 irq_ret
= IRQ_HANDLED
;
867 spin_unlock_irqrestore(&hwif
->lock
, flags
);
870 ide_unlock_host(hwif
->host
);
871 ide_plug_device(drive
);
876 EXPORT_SYMBOL_GPL(ide_intr
);
878 void ide_pad_transfer(ide_drive_t
*drive
, int write
, int len
)
880 ide_hwif_t
*hwif
= drive
->hwif
;
885 hwif
->tp_ops
->output_data(drive
, NULL
, buf
, min(4, len
));
887 hwif
->tp_ops
->input_data(drive
, NULL
, buf
, min(4, len
));
891 EXPORT_SYMBOL_GPL(ide_pad_transfer
);