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);
75 * ide_end_request - complete an IDE I/O
76 * @drive: IDE device for the I/O
78 * @nr_sectors: number of sectors completed
80 * This is our end_request wrapper function. We complete the I/O
81 * update random number input and dequeue the request, which if
82 * it was tagged may be out of order.
85 int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
87 unsigned int nr_bytes = nr_sectors << 9;
88 struct request *rq = drive->hwif->rq;
92 if (blk_pc_request(rq))
93 nr_bytes = rq->data_len;
95 nr_bytes = rq->hard_cur_sectors << 9;
99 * if failfast is set on a request, override number of sectors
100 * and complete the whole request right now
102 if (blk_noretry_request(rq) && uptodate <= 0)
103 nr_bytes = rq->hard_nr_sectors << 9;
106 error = uptodate ? uptodate : -EIO;
108 rc = ide_end_rq(drive, rq, error, nr_bytes);
110 drive->hwif->rq = NULL;
114 EXPORT_SYMBOL(ide_end_request);
116 void ide_complete_cmd(ide_drive_t *drive, struct ide_cmd *cmd, u8 stat, u8 err)
118 struct ide_taskfile *tf = &cmd->tf;
119 struct request *rq = cmd->rq;
120 u8 tf_cmd = tf->command;
125 drive->hwif->tp_ops->tf_read(drive, cmd);
127 if ((cmd->tf_flags & IDE_TFLAG_CUSTOM_HANDLER) &&
128 tf_cmd == ATA_CMD_IDLEIMMEDIATE) {
129 if (tf->lbal != 0xc4) {
130 printk(KERN_ERR "%s: head unload failed!\n",
132 ide_tf_dump(drive->name, tf);
134 drive->dev_flags |= IDE_DFLAG_PARKED;
137 if (rq && rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
138 memcpy(rq->special, cmd, sizeof(*cmd));
140 if (cmd->tf_flags & IDE_TFLAG_DYN)
144 void ide_complete_rq(ide_drive_t *drive, int error)
146 ide_hwif_t *hwif = drive->hwif;
147 struct request *rq = hwif->rq;
151 if (unlikely(blk_end_request(rq, error, blk_rq_bytes(rq))))
154 EXPORT_SYMBOL(ide_complete_rq);
156 void ide_kill_rq(ide_drive_t *drive, struct request *rq)
158 u8 drv_req = blk_special_request(rq) && rq->rq_disk;
159 u8 media = drive->media;
161 drive->failed_pc = NULL;
163 if ((media == ide_floppy || media == ide_tape) && drv_req) {
165 ide_complete_rq(drive, 0);
167 if (media == ide_tape)
168 rq->errors = IDE_DRV_ERROR_GENERAL;
169 else if (blk_fs_request(rq) == 0 && rq->errors == 0)
171 ide_end_request(drive, 0, 0);
175 static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
177 tf->nsect = drive->sect;
178 tf->lbal = drive->sect;
179 tf->lbam = drive->cyl;
180 tf->lbah = drive->cyl >> 8;
181 tf->device = (drive->head - 1) | drive->select;
182 tf->command = ATA_CMD_INIT_DEV_PARAMS;
185 static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
187 tf->nsect = drive->sect;
188 tf->command = ATA_CMD_RESTORE;
191 static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
193 tf->nsect = drive->mult_req;
194 tf->command = ATA_CMD_SET_MULTI;
197 static ide_startstop_t ide_disk_special(ide_drive_t *drive)
199 special_t *s = &drive->special;
202 memset(&cmd, 0, sizeof(cmd));
203 cmd.protocol = ATA_PROT_NODATA;
205 if (s->b.set_geometry) {
206 s->b.set_geometry = 0;
207 ide_tf_set_specify_cmd(drive, &cmd.tf);
208 } else if (s->b.recalibrate) {
209 s->b.recalibrate = 0;
210 ide_tf_set_restore_cmd(drive, &cmd.tf);
211 } else if (s->b.set_multmode) {
212 s->b.set_multmode = 0;
213 ide_tf_set_setmult_cmd(drive, &cmd.tf);
215 int special = s->all;
217 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
221 cmd.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE |
222 IDE_TFLAG_CUSTOM_HANDLER;
224 do_rw_taskfile(drive, &cmd);
230 * do_special - issue some special commands
231 * @drive: drive the command is for
233 * do_special() is used to issue ATA_CMD_INIT_DEV_PARAMS,
234 * ATA_CMD_RESTORE and ATA_CMD_SET_MULTI commands to a drive.
236 * It used to do much more, but has been scaled back.
239 static ide_startstop_t do_special (ide_drive_t *drive)
241 special_t *s = &drive->special;
244 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
246 if (drive->media == ide_disk)
247 return ide_disk_special(drive);
254 void ide_map_sg(ide_drive_t *drive, struct request *rq)
256 ide_hwif_t *hwif = drive->hwif;
257 struct ide_cmd *cmd = &hwif->cmd;
258 struct scatterlist *sg = hwif->sg_table;
260 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
261 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
263 } else if (!rq->bio) {
264 sg_init_one(sg, rq->data, rq->data_len);
267 cmd->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
269 EXPORT_SYMBOL_GPL(ide_map_sg);
271 void ide_init_sg_cmd(struct ide_cmd *cmd, int nsect)
273 cmd->nsect = cmd->nleft = nsect;
277 EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
280 * execute_drive_command - issue special drive command
281 * @drive: the drive to issue the command on
282 * @rq: the request structure holding the command
284 * execute_drive_cmd() issues a special drive command, usually
285 * initiated by ioctl() from the external hdparm program. The
286 * command can be a drive command, drive task or taskfile
287 * operation. Weirdly you can call it with NULL to wait for
288 * all commands to finish. Don't do this as that is due to change
291 static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
294 struct ide_cmd *cmd = rq->special;
297 if (cmd->protocol == ATA_PROT_PIO) {
298 ide_init_sg_cmd(cmd, rq->nr_sectors);
299 ide_map_sg(drive, rq);
302 return do_rw_taskfile(drive, cmd);
306 * NULL is actually a valid way of waiting for
307 * all current requests to be flushed from the queue.
310 printk("%s: DRIVE_CMD (null)\n", drive->name);
313 ide_complete_rq(drive, 0);
318 static ide_startstop_t ide_special_rq(ide_drive_t *drive, struct request *rq)
324 case REQ_UNPARK_HEADS:
325 return ide_do_park_unpark(drive, rq);
326 case REQ_DEVSET_EXEC:
327 return ide_do_devset(drive, rq);
328 case REQ_DRIVE_RESET:
329 return ide_do_reset(drive);
336 * start_request - start of I/O and command issuing for IDE
338 * start_request() initiates handling of a new I/O request. It
339 * accepts commands and I/O (read/write) requests.
341 * FIXME: this function needs a rename
344 static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
346 ide_startstop_t startstop;
348 BUG_ON(!blk_rq_started(rq));
351 printk("%s: start_request: current=0x%08lx\n",
352 drive->hwif->name, (unsigned long) rq);
355 /* bail early if we've exceeded max_failures */
356 if (drive->max_failures && (drive->failures > drive->max_failures)) {
357 rq->cmd_flags |= REQ_FAILED;
361 if (blk_pm_request(rq))
362 ide_check_pm_state(drive, rq);
365 if (ide_wait_stat(&startstop, drive, drive->ready_stat,
366 ATA_BUSY | ATA_DRQ, WAIT_READY)) {
367 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
370 if (!drive->special.all) {
371 struct ide_driver *drv;
374 * We reset the drive so we need to issue a SETFEATURES.
375 * Do it _after_ do_special() restored device parameters.
377 if (drive->current_speed == 0xff)
378 ide_config_drive_speed(drive, drive->desired_speed);
380 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
381 return execute_drive_cmd(drive, rq);
382 else if (blk_pm_request(rq)) {
383 struct request_pm_state *pm = rq->data;
385 printk("%s: start_power_step(step: %d)\n",
386 drive->name, pm->pm_step);
388 startstop = ide_start_power_step(drive, rq);
389 if (startstop == ide_stopped &&
390 pm->pm_step == IDE_PM_COMPLETED)
391 ide_complete_pm_rq(drive, rq);
393 } else if (!rq->rq_disk && blk_special_request(rq))
395 * TODO: Once all ULDs have been modified to
396 * check for specific op codes rather than
397 * blindly accepting any special request, the
398 * check for ->rq_disk above may be replaced
399 * by a more suitable mechanism or even
402 return ide_special_rq(drive, rq);
404 drv = *(struct ide_driver **)rq->rq_disk->private_data;
406 return drv->do_request(drive, rq, rq->sector);
408 return do_special(drive);
410 ide_kill_rq(drive, rq);
415 * ide_stall_queue - pause an IDE device
416 * @drive: drive to stall
417 * @timeout: time to stall for (jiffies)
419 * ide_stall_queue() can be used by a drive to give excess bandwidth back
420 * to the port by sleeping for timeout jiffies.
423 void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
425 if (timeout > WAIT_WORSTCASE)
426 timeout = WAIT_WORSTCASE;
427 drive->sleep = timeout + jiffies;
428 drive->dev_flags |= IDE_DFLAG_SLEEPING;
430 EXPORT_SYMBOL(ide_stall_queue);
432 static inline int ide_lock_port(ide_hwif_t *hwif)
442 static inline void ide_unlock_port(ide_hwif_t *hwif)
447 static inline int ide_lock_host(struct ide_host *host, ide_hwif_t *hwif)
451 if (host->host_flags & IDE_HFLAG_SERIALIZE) {
452 rc = test_and_set_bit_lock(IDE_HOST_BUSY, &host->host_busy);
455 host->get_lock(ide_intr, hwif);
461 static inline void ide_unlock_host(struct ide_host *host)
463 if (host->host_flags & IDE_HFLAG_SERIALIZE) {
464 if (host->release_lock)
465 host->release_lock();
466 clear_bit_unlock(IDE_HOST_BUSY, &host->host_busy);
471 * Issue a new request to a device.
473 void do_ide_request(struct request_queue *q)
475 ide_drive_t *drive = q->queuedata;
476 ide_hwif_t *hwif = drive->hwif;
477 struct ide_host *host = hwif->host;
478 struct request *rq = NULL;
479 ide_startstop_t startstop;
482 * drive is doing pre-flush, ordered write, post-flush sequence. even
483 * though that is 3 requests, it must be seen as a single transaction.
484 * we must not preempt this drive until that is complete
486 if (blk_queue_flushing(q))
488 * small race where queue could get replugged during
489 * the 3-request flush cycle, just yank the plug since
490 * we want it to finish asap
494 spin_unlock_irq(q->queue_lock);
496 if (ide_lock_host(host, hwif))
499 spin_lock_irq(&hwif->lock);
501 if (!ide_lock_port(hwif)) {
502 ide_hwif_t *prev_port;
504 prev_port = hwif->host->cur_port;
507 if (drive->dev_flags & IDE_DFLAG_SLEEPING) {
508 if (time_before(drive->sleep, jiffies)) {
509 ide_unlock_port(hwif);
514 if ((hwif->host->host_flags & IDE_HFLAG_SERIALIZE) &&
517 * set nIEN for previous port, drives in the
518 * quirk_list may not like intr setups/cleanups
520 if (prev_port && prev_port->cur_dev->quirk_list == 0)
521 prev_port->tp_ops->set_irq(prev_port, 0);
523 hwif->host->cur_port = hwif;
525 hwif->cur_dev = drive;
526 drive->dev_flags &= ~(IDE_DFLAG_SLEEPING | IDE_DFLAG_PARKED);
528 spin_unlock_irq(&hwif->lock);
529 spin_lock_irq(q->queue_lock);
531 * we know that the queue isn't empty, but this can happen
532 * if the q->prep_rq_fn() decides to kill a request
534 rq = elv_next_request(drive->queue);
535 spin_unlock_irq(q->queue_lock);
536 spin_lock_irq(&hwif->lock);
539 ide_unlock_port(hwif);
544 * Sanity: don't accept a request that isn't a PM request
545 * if we are currently power managed. This is very important as
546 * blk_stop_queue() doesn't prevent the elv_next_request()
547 * above to return us whatever is in the queue. Since we call
548 * ide_do_request() ourselves, we end up taking requests while
549 * the queue is blocked...
551 * We let requests forced at head of queue with ide-preempt
552 * though. I hope that doesn't happen too much, hopefully not
553 * unless the subdriver triggers such a thing in its own PM
556 if ((drive->dev_flags & IDE_DFLAG_BLOCKED) &&
557 blk_pm_request(rq) == 0 &&
558 (rq->cmd_flags & REQ_PREEMPT) == 0) {
559 /* there should be no pending command at this point */
560 ide_unlock_port(hwif);
566 spin_unlock_irq(&hwif->lock);
567 startstop = start_request(drive, rq);
568 spin_lock_irq(&hwif->lock);
570 if (startstop == ide_stopped)
575 spin_unlock_irq(&hwif->lock);
577 ide_unlock_host(host);
578 spin_lock_irq(q->queue_lock);
582 spin_unlock_irq(&hwif->lock);
583 ide_unlock_host(host);
585 spin_lock_irq(q->queue_lock);
587 if (!elv_queue_empty(q))
591 static void ide_plug_device(ide_drive_t *drive)
593 struct request_queue *q = drive->queue;
596 spin_lock_irqsave(q->queue_lock, flags);
597 if (!elv_queue_empty(q))
599 spin_unlock_irqrestore(q->queue_lock, flags);
602 static int drive_is_ready(ide_drive_t *drive)
604 ide_hwif_t *hwif = drive->hwif;
607 if (drive->waiting_for_dma)
608 return hwif->dma_ops->dma_test_irq(drive);
610 if (hwif->io_ports.ctl_addr &&
611 (hwif->host_flags & IDE_HFLAG_BROKEN_ALTSTATUS) == 0)
612 stat = hwif->tp_ops->read_altstatus(hwif);
614 /* Note: this may clear a pending IRQ!! */
615 stat = hwif->tp_ops->read_status(hwif);
618 /* drive busy: definitely not interrupting */
621 /* drive ready: *might* be interrupting */
626 * ide_timer_expiry - handle lack of an IDE interrupt
627 * @data: timer callback magic (hwif)
629 * An IDE command has timed out before the expected drive return
630 * occurred. At this point we attempt to clean up the current
631 * mess. If the current handler includes an expiry handler then
632 * we invoke the expiry handler, and providing it is happy the
633 * work is done. If that fails we apply generic recovery rules
634 * invoking the handler and checking the drive DMA status. We
635 * have an excessively incestuous relationship with the DMA
636 * logic that wants cleaning up.
639 void ide_timer_expiry (unsigned long data)
641 ide_hwif_t *hwif = (ide_hwif_t *)data;
642 ide_drive_t *uninitialized_var(drive);
643 ide_handler_t *handler;
648 spin_lock_irqsave(&hwif->lock, flags);
650 handler = hwif->handler;
652 if (handler == NULL || hwif->req_gen != hwif->req_gen_timer) {
654 * Either a marginal timeout occurred
655 * (got the interrupt just as timer expired),
656 * or we were "sleeping" to give other devices a chance.
657 * Either way, we don't really want to complain about anything.
660 ide_expiry_t *expiry = hwif->expiry;
661 ide_startstop_t startstop = ide_stopped;
663 drive = hwif->cur_dev;
666 wait = expiry(drive);
667 if (wait > 0) { /* continue */
669 hwif->timer.expires = jiffies + wait;
670 hwif->req_gen_timer = hwif->req_gen;
671 add_timer(&hwif->timer);
672 spin_unlock_irqrestore(&hwif->lock, flags);
676 hwif->handler = NULL;
678 * We need to simulate a real interrupt when invoking
679 * the handler() function, which means we need to
680 * globally mask the specific IRQ:
682 spin_unlock(&hwif->lock);
683 /* disable_irq_nosync ?? */
684 disable_irq(hwif->irq);
685 /* local CPU only, as if we were handling an interrupt */
688 startstop = handler(drive);
689 } else if (drive_is_ready(drive)) {
690 if (drive->waiting_for_dma)
691 hwif->dma_ops->dma_lost_irq(drive);
693 hwif->ack_intr(hwif);
694 printk(KERN_WARNING "%s: lost interrupt\n",
696 startstop = handler(drive);
698 if (drive->waiting_for_dma)
699 startstop = ide_dma_timeout_retry(drive, wait);
701 startstop = ide_error(drive, "irq timeout",
702 hwif->tp_ops->read_status(hwif));
704 spin_lock_irq(&hwif->lock);
705 enable_irq(hwif->irq);
706 if (startstop == ide_stopped) {
707 ide_unlock_port(hwif);
711 spin_unlock_irqrestore(&hwif->lock, flags);
714 ide_unlock_host(hwif->host);
715 ide_plug_device(drive);
720 * unexpected_intr - handle an unexpected IDE interrupt
721 * @irq: interrupt line
722 * @hwif: port being processed
724 * There's nothing really useful we can do with an unexpected interrupt,
725 * other than reading the status register (to clear it), and logging it.
726 * There should be no way that an irq can happen before we're ready for it,
727 * so we needn't worry much about losing an "important" interrupt here.
729 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
730 * the drive enters "idle", "standby", or "sleep" mode, so if the status
731 * looks "good", we just ignore the interrupt completely.
733 * This routine assumes __cli() is in effect when called.
735 * If an unexpected interrupt happens on irq15 while we are handling irq14
736 * and if the two interfaces are "serialized" (CMD640), then it looks like
737 * we could screw up by interfering with a new request being set up for
740 * In reality, this is a non-issue. The new command is not sent unless
741 * the drive is ready to accept one, in which case we know the drive is
742 * not trying to interrupt us. And ide_set_handler() is always invoked
743 * before completing the issuance of any new drive command, so we will not
744 * be accidentally invoked as a result of any valid command completion
748 static void unexpected_intr(int irq, ide_hwif_t *hwif)
750 u8 stat = hwif->tp_ops->read_status(hwif);
752 if (!OK_STAT(stat, ATA_DRDY, BAD_STAT)) {
753 /* Try to not flood the console with msgs */
754 static unsigned long last_msgtime, count;
757 if (time_after(jiffies, last_msgtime + HZ)) {
758 last_msgtime = jiffies;
759 printk(KERN_ERR "%s: unexpected interrupt, "
760 "status=0x%02x, count=%ld\n",
761 hwif->name, stat, count);
767 * ide_intr - default IDE interrupt handler
768 * @irq: interrupt number
770 * @regs: unused weirdness from the kernel irq layer
772 * This is the default IRQ handler for the IDE layer. You should
773 * not need to override it. If you do be aware it is subtle in
776 * hwif is the interface in the group currently performing
777 * a command. hwif->cur_dev is the drive and hwif->handler is
778 * the IRQ handler to call. As we issue a command the handlers
779 * step through multiple states, reassigning the handler to the
780 * next step in the process. Unlike a smart SCSI controller IDE
781 * expects the main processor to sequence the various transfer
782 * stages. We also manage a poll timer to catch up with most
783 * timeout situations. There are still a few where the handlers
784 * don't ever decide to give up.
786 * The handler eventually returns ide_stopped to indicate the
787 * request completed. At this point we issue the next request
788 * on the port and the process begins again.
791 irqreturn_t ide_intr (int irq, void *dev_id)
793 ide_hwif_t *hwif = (ide_hwif_t *)dev_id;
794 struct ide_host *host = hwif->host;
795 ide_drive_t *uninitialized_var(drive);
796 ide_handler_t *handler;
798 ide_startstop_t startstop;
799 irqreturn_t irq_ret = IRQ_NONE;
802 if (host->host_flags & IDE_HFLAG_SERIALIZE) {
803 if (hwif != host->cur_port)
807 spin_lock_irqsave(&hwif->lock, flags);
809 if (hwif->ack_intr && hwif->ack_intr(hwif) == 0)
812 handler = hwif->handler;
814 if (handler == NULL || hwif->polling) {
816 * Not expecting an interrupt from this drive.
817 * That means this could be:
818 * (1) an interrupt from another PCI device
819 * sharing the same PCI INT# as us.
820 * or (2) a drive just entered sleep or standby mode,
821 * and is interrupting to let us know.
822 * or (3) a spurious interrupt of unknown origin.
824 * For PCI, we cannot tell the difference,
825 * so in that case we just ignore it and hope it goes away.
827 if ((host->irq_flags & IRQF_SHARED) == 0) {
829 * Probably not a shared PCI interrupt,
830 * so we can safely try to do something about it:
832 unexpected_intr(irq, hwif);
835 * Whack the status register, just in case
836 * we have a leftover pending IRQ.
838 (void)hwif->tp_ops->read_status(hwif);
843 drive = hwif->cur_dev;
845 if (!drive_is_ready(drive))
847 * This happens regularly when we share a PCI IRQ with
848 * another device. Unfortunately, it can also happen
849 * with some buggy drives that trigger the IRQ before
850 * their status register is up to date. Hopefully we have
851 * enough advance overhead that the latter isn't a problem.
855 hwif->handler = NULL;
857 del_timer(&hwif->timer);
858 spin_unlock(&hwif->lock);
860 if (hwif->port_ops && hwif->port_ops->clear_irq)
861 hwif->port_ops->clear_irq(drive);
863 if (drive->dev_flags & IDE_DFLAG_UNMASK)
864 local_irq_enable_in_hardirq();
866 /* service this interrupt, may set handler for next interrupt */
867 startstop = handler(drive);
869 spin_lock_irq(&hwif->lock);
871 * Note that handler() may have set things up for another
872 * interrupt to occur soon, but it cannot happen until
873 * we exit from this routine, because it will be the
874 * same irq as is currently being serviced here, and Linux
875 * won't allow another of the same (on any CPU) until we return.
877 if (startstop == ide_stopped) {
878 BUG_ON(hwif->handler);
879 ide_unlock_port(hwif);
882 irq_ret = IRQ_HANDLED;
884 spin_unlock_irqrestore(&hwif->lock, flags);
887 ide_unlock_host(hwif->host);
888 ide_plug_device(drive);
893 EXPORT_SYMBOL_GPL(ide_intr);
895 void ide_pad_transfer(ide_drive_t *drive, int write, int len)
897 ide_hwif_t *hwif = drive->hwif;
902 hwif->tp_ops->output_data(drive, NULL, buf, min(4, len));
904 hwif->tp_ops->input_data(drive, NULL, buf, min(4, len));
908 EXPORT_SYMBOL_GPL(ide_pad_transfer);