Commit Graph

258 Commits

Author SHA1 Message Date
Jeff Garzik 16454445e1 [libata] sata_vsc: build fix after PCI MSI feature addition
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:31 -05:00
Dan Wolstenholme 7cbaa86b93 [libata] sata_vsc: support PCI MSI
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:31 -05:00
Tejun Heo 553c4aa630 libata: handle pci_enable_device() failure while resuming
Handle pci_enable_device() failure while resuming.  This patch kills
the "ignoring return value of 'pci_enable_device'" warning message and
propagates __must_check through ata_pci_device_do_resume().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:30 -05:00
Tejun Heo 8bfa79fcb8 libata: use ata_id_c_string()
There were several places where ATA ID strings are manually terminated
and in some places possibly unterminated strings were passed to string
functions which don't limit length like strstr().  This patch converts
all of them over to ata_id_c_string().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:30 -05:00
Tejun Heo a0cf733b33 libata: straighten out ATA_ID_* constants
* Kill _OFS suffixes in ATA_ID_{SERNO|FW_REV|PROD}_OFS for consistency
  with other ATA_ID_* constants.

* Kill ATA_SERNO_LEN

* Add and use ATA_ID_SERNO_LEN, ATA_ID_FW_REV_LEN and ATA_ID_PROD_LEN.
  This change also makes ata_device_blacklisted() use proper length
  for fwrev.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:30 -05:00
Robert Hancock cdf56bcf14 sata_nv: add suspend/resume support v3 (Resubmit)
Thoughts from Jeff & company on merging the patch below into libata-dev?
This has been in the -mm tree for over a month now, I haven't heard any
complaints about regressions..

Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:30 -05:00
Adrian Bunk 7102d230d6 drivers/ata/: make 4 functions static
This patch makes the following needlessly global functions static:
- libata-core.c: ata_qc_complete_internal()
- libata-scsi.c: ata_scsi_qc_new()
- libata-scsi.c: ata_dump_status()
- libata-scsi.c: ata_to_sense_error()

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:30 -05:00
Alan 904dbd1307 ahci: Remove jmicron fixup
The AHCI set up is handled properly along with the other bits in the
JMICRON quirk. Remove the code whacking it in ahci.c as its un-needed and
also blindly fiddles with bits it doesn't own.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:30 -05:00
Alan 4112e16a7c libata-sff: Don't try and activate channels which are not in use
An ATA controller in native mode may have one or more channels disabled
and not assigned resources. In that case the existing code crashes trying
to access I/O ports 0-7.

Add the neccessary check.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:30 -05:00
Alan d73f30e1c9 sata_via: PATA support
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:30 -05:00
Jakub W. Jozwicki J 7dcbc1f2c8 pata_sis: implement laptop list and add ASUS A6K/A6U
In ASUS A6K/A6U hdd is connected to SiS 96x via 40c cable, however it
is short cable and is UDMA66 capable.

tj: fixed if () conditionals
ah: fixed infinite loop

Signed-off-by: Jakub W. Jozwicki <jakub007@go2.pl>
Cc: Andreas Henriksson <andreas@fatal.se>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:29 -05:00
J J babfb682c9 ata_piix: add ICH7 on Acer 3682WLMi to laptop list
In Acer Aspire hdd is connected to ICH7 via 40c cable, however it is
short cable and it is UDMA66 capable.

Signed-off-by: J J <jakub007@go2.pl>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:29 -05:00
Conke Hu c9f89475a5 Add pci class code for SATA & AHCI, and replace some magic numbers.
Signed-off-by: Conke Hu <conke.hu@amd.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:29 -05:00
Mikael Pettersson 95006188cb sata_promise: ATAPI support
This patch adds ATAPI support to the sata_promise driver.
This has been tested on both first- and second-generation
chips (20378 and 20575), and with both SATAPI and PATAPI
devices. CD-writing works.

SATAPI DMA works on second-generation chips, but on
first-generation chips SATAPI is limited to PIO due
to what appears to be HW limitations.
PATAPI DMA works on both first- and second-generation
chips, but requires the separate PATA support patch
before it can be used on TX2plus chips.

The functional changes to the driver are:
- remove ATA_FLAG_NO_ATAPI from PDC_COMMON_FLAGS
- add ->check_atapi_dma() operation to enable DMA for bulk data
  transfers but force PIO for other ATAPI commands; this filter
  is from Promise's driver and largely matches pata_pdc207x.c
- use a more restrictive ->check_atapi_dma() on first-generation
  chips to force SATAPI to always use PIO
- add handling of ATAPI protocols to pdc_qc_prep(), pdc_host_intr(),
  and pdc_qc_issue_prot(): ATAPI_DMA is handled by the driver
  while non-DMA protocols are handed over to libata generic code
- add pdc_issue_atapi_pkt_cmd() to handle the initial steps in
  issuing ATAPI DMA commands before sending the actual CDB;
  this procedure was ported from Promise's driver

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:29 -05:00
Mikael Pettersson 870ae337d5 sata_promise: TX2plus PATA support
This patch implements a simple way of setting up per-port
flags on the SATA+PATA Promise TX2plus chips, which is a
prerequisite for supporting the PATA port on those chips.

It is based on the observation that ap->flags isn't really
used until after ->port_start() has been invoked. So it
places the "exceptional" per-port flags array in the driver's
private host structure, and uses it in ->port_start() to
finalise the port's flags.

This patch obsoletes the #promise-sata-pata branch included
in the #all branch.

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:29 -05:00
Arjan van de Ven 7a44e910f4 [PATCH] user of the jiffies rounding patch: ATA subsystem
This patch introduces users of the round_jiffies() function: ATA subsystem

This delayed work is of the "about once a second" variety and can be rounded
to coincide with other wakers.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:29 -05:00
Jeff Garzik f20b16ff7c [libata] trim trailing whitespace
Most of these contributed by that mysterious figger known as A.C.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:29 -05:00
Sylvain Munaut 155d2916d9 [PATCH] libata: Add support for the MPC52xx ATA controller
This patch adds initial libata support for the Freescale
MPC5200 integrated IDE controller.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:29 -05:00
Alan 9b13b682a6 [PATCH] pata_it8213: Add new driver for the IT8213 card
Add a driver for the IT8213 which is a single channel ICH-ish PATA
controller.  As it is very different to the IT8211/2 it gets its own
driver.  There is a legacy drivers/ide driver also available and I'll post
that once I get time to test it all out (probably early January).  If
anyone else needs the drivers/ide driver and wants to do the merge for
drivers/ide (Bart ??) then I'll forward it.

[akpm@osdl.org: add PCI ID, constify needed_pio[]]
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:28 -05:00
Uwe Koziolek 3f3e7313e4 [PATCH] sata_sis: support SiS966/966L
The SiS966/966L has different PCI-IDs for native mode and AHCI mode.
The SiS966 supports four SATA ports only in native mode.

Added additional PCI-ID 0x0183 for SiS965/965L.

this patch is based on the code from David Wang from SiS Corporation published on SiS Website.

Signed-off-by: Uwe Koziolek <uwe.koziolek@gmx.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:28 -05:00
Al Viro 04d4f7a114 [PATCH] ahci: trivial endianness annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-09 09:14:07 -08:00
Al Viro 92ccc5f755 [PATCH] sata_svw: trivial iomem annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-09 09:14:07 -08:00
Brian King 49c8042996 libata: Initialize nbytes for internal sg commands
Some LLDDs, like ipr, use nbytes and pad_len to determine
the total data transfer length of a command. Make sure
nbytes gets initialized for internally generated commands.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-02 11:52:05 -05:00
Alan 05c39e502e pata_via: Correct missing comments
The 8237S was added to the chipsets but not to the comments. Fix this

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-02 11:52:05 -05:00
Alan 54494f3a83 pata_atiixp: propogate cable detection hack from drivers/ide to the new driver
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-02 11:52:05 -05:00
Tejun Heo 7728098967 ahci/pata_jmicron: fix JMicron quirk
For all JMicrons except for 361 and 368, AHCI mode enable bits in the
Control(1) should be set.  This used to be done in both ahci and
pata_jmicron but while moving programming to PCI quirk, it was removed
from ahci part while still left in pata_jmicron.

The implemented JMicron PCI quirk was incorrect in that it didn't
program AHCI mode enable bits.  If pata_jmicron is loaded first and
programs those bits, the ahci ports work; otherwise, ahci device
detection fails miserably.

This patch makes JMicron PCI quirk clear SATA IDE mode bits and set
AHCI mode bits and remove the respective part from pata_jmicron.
Tested on JMB361, 363 and 368.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-02 11:52:05 -05:00
Linus Torvalds 8c8c4bafc3 Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  libata: fix translation for START STOP UNIT
  libata-scsi: ata_task_ioctl should return ATA registers from sense data
  pata_platform: set_mode fix
  ata_if_xfermask() word 51 fix
  pata_sil680: PIO1 taskfile transfers overclocking fix (repost)
  libata: fix ata_eh_suspend() return value
  ahci: port_no should be used when clearing IRQ in ahci_thaw()

Fix trivial conflict in drivers/ata/pata_platform.c manually
2007-01-30 08:46:17 -08:00
Linus Torvalds 597049ccd7 Merge master.kernel.org:/pub/scm/linux/kernel/git/bart/ide-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/bart/ide-2.6:
  via82cxxx/pata_via: correct PCI_DEVICE_ID_VIA_SATA_EIDE ID and add support for CX700 and 8237S
  ide: unregister idepnp driver on unload
  ide: add missing __init tags to IDE PCI host drivers
  ia64: add pci_get_legacy_ide_irq()
  ide/generic: Jmicron has its own drivers now
  atiixp.c: add cable detection support for ATI IDE
  atiixp.c: sb600 ide only has one channel
  atiixp.c: remove unused code
  jmicron: fix warning
  ide: update MAINTAINERS entry
2007-01-30 08:41:27 -08:00
Al Viro 161c888b0b [PATCH] pata_platform: fallout from set_mode() change
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-30 08:39:20 -08:00
Robert Hancock 78981a7c6c libata: fix translation for START STOP UNIT
libata's SCSI translation for the SCSI START STOP UNIT command with the
START bit clear (i.e.  stopping the drive) appears to be incorrect.  It
sends an ATA STANDBY command with the time period set to 0, which the code
comment says means "now", but the ATA standard says this means disable the
standby timer, which effectively does nothing.  Change this to issue a
STANDBY IMMEDIATE command which will actually spin the drive down.  The SAT
(SCSI/ATA Translation) standard revision 9 concurs with this choice.

Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-30 09:20:39 -05:00
David Milburn af068bd1de libata-scsi: ata_task_ioctl should return ATA registers from sense data
User applications using the HDIO_DRIVE_TASK ioctl through libata expect
specific ATA registers to be returned to userspace.  Verified that
ata_task_ioctl correctly returns register values to the smartctl
application.

Signed-off-by: David Milburn <dmilburn@redhat.com>
Acked-by: Tejun Heo <htejun@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-30 09:20:39 -05:00
Andrew Morton 2ca6611b1f pata_platform: set_mode fix
drivers/ata/pata_platform.c:85: warning: initialization from incompatible pointer type

Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-30 09:20:39 -05:00
Lennert Buytenhek 7a0f1c8a4b ata_if_xfermask() word 51 fix
If word 53 bit 1 isn't set, the maximum PIO mode is indicated by
the upper 8 bits of word 51, not the lower 8 bits.  Fixes PIO mode
detection on old Compact Flash cards.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-30 09:14:56 -05:00
Sergei Shtylyov 5dcade90db pata_sil680: PIO1 taskfile transfers overclocking fix (repost)
Fix PIO mode 1 overclocked taskfile transfers -- probably a typo carried over
from drivers/ide/pci/siimage.c where I've found it by documentation check...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-30 09:14:56 -05:00
Josepch Chan e0b874df14 via82cxxx/pata_via: correct PCI_DEVICE_ID_VIA_SATA_EIDE ID and add support for CX700 and 8237S
This patch:
* Corrects the wrong device ID of PCI_DEVICE_ID_VIA_SATA_EIDE
  from 0x0581 to 0x5324.
* Adds VIA CX700 and VT8237S support in drivers/ide/pci/via82cxxx.c
* Adds VIA VT8237S support in drivers/ata/pata_via.c

Signed-off-by: Josepch Chan <josephchan@via.com.tw>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2007-01-27 13:47:08 +01:00
Tejun Heo 03ee5b1cdd libata: fix ata_eh_suspend() return value
ata_eh_suspend() was returning 0 regardless of failure.  This bug has
potential to lose data on suspend.  Fix it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-27 03:21:26 -05:00
Tejun Heo a718728f9e ahci: port_no should be used when clearing IRQ in ahci_thaw()
ap->id is logcial port ID which is unique among all ATA ports and
doesn't have anything to do with hardware port index.  ap->port_no is
the hardware port index and thus should be used when clearing IRQ mask
in ahci_thaw().

This problem has been spotted by Jeff Garzik <jgarzik@pobox.com>.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-27 02:50:36 -05:00
David Woodhouse 8cdf92a98f Fix Maple PATA IRQ assignment.
On the Maple board, the AMD8111 IDE is in legacy mode... except that it
appears on IRQ 20 instead of IRQ 15. For drivers/ide this was handled by
the architecture's "pci_get_legacy_ide_irq()" function, but in libata we
just hard-code the numbers 14 and 15.

This patch provides asm-powerpc/libata-portmap.h which maps the IRQ as
appropriate, having added a pci_dev argument to the
ATA_{PRIM,SECOND}ARY_IRQ macros.

There's probably a better way to do this -- especially if we observe
that the _only_ case in which this seemingly-generic
"pci_get_legacy_ide_irq()" function returns anything other than 14 and
15 for primary and secondary respectively is the case of the AMD8111 on
the Maple board -- couldn't we handle that with a special case in the
pata_amd driver, or perhaps with a PCI quirk for Maple to switch it into
native mode during early boot and assign resources properly?

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-26 17:27:40 -05:00
Tejun Heo dfd7a3db38 ahci: use 0x80 as wait stat value instead of 0xff
Before hardreset, ahci initialized stat part of received FIS area to
0xff to wait for the first D2H Reg FIS which would change the value to
device ready state.  This used to work but now libata considers status
value of 0xff as device not present making this wait prone to failure.

This patch makes ahci use 0x80 for the wait stat value instead of
0xff to fix the above problem.

Signed-off-by: Tejun Heo <htejun@gmail.com>

 drivers/ata/ahci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-26 17:24:07 -05:00
Tejun Heo d025987217 sata_via: style clean up, no indirect method call in LLD
Call ata_bmdma_irq_clear() directly instead of through
ap->ops->irq_clear() according to libata style guideline.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-26 17:24:07 -05:00
Tejun Heo 6096b63e25 ahci: fix endianness in spurious interrupt message
Fix endianness in spurious interrupt message.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-26 17:24:07 -05:00
Alan 61dd08c6c8 libata-sff: Don't call bmdma_stop on non DMA capable controllers
Fixes bogus accesses to ports 0-15 with a non DMA capable controller.
This I think should go in for 2.6.20

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-25 18:27:16 -05:00
Tejun Heo b2a8bbe67d libata: implement ATA_FLAG_IGN_SIMPLEX and use it in sata_uli
Some uli controllers have stuck SIMPLEX bit which can't be cleared
with ata_pci_clear_simplex(), but the controller is capable of doing
DMAs on both channels simultaneously.  Implement ATA_FLAG_IGN_SIMPLEX
which makes libata ignore the simplex bit and use it in sata_uli.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-25 17:26:01 -05:00
Tejun Heo 0291f95fdb ahci: improve and limit spurious interrupt messages, take#3
We're still seeing a lot of issues with NCQ implementation in drive
firmwares.  Sprious FISes during NCQ command phase occur on many
drives and some of them seem potentially dangerous (at least to me).
Until we find the solution, spurious messages can give us more info.
Improve and limit them such that more info can be reported while not
disturbing users too much.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-25 17:22:47 -05:00
Tejun Heo 17234246eb sata_via: don't diddle with ATA_NIEN in ->freeze
vt6420 completely loses its ability to raise IRQ for ATAPI devices if
ATA_NIEN is diddled with in ->freeze.  Further investigation is
necessary to determine whether this problem is shared on other
controllers but it doesn't seem to be at this point.

Make vt6420's ->freeze only clear IRQ to fix this problem.  This makes
vt6420 relatively more prone to IRQ storms but the controller is way
too braindamaged to worry about that anyway.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-25 17:22:47 -05:00
Alan b229a7b0ae libata: set_mode, Fix the FIXME
When set_mode() changed ->set_mode didn't adapt. This makes the needed
changes and removes the relevant FIXME case.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-24 19:55:16 -05:00
Alan a52865c239 libata hpt3xn: Hopefully sort out the DPLL logic versus the vendor code
Rather than ending up with two layers of negation jut rename the variable
and lose one.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-24 19:52:31 -05:00
Alan 6a40da02be libata cmd64x: whack into a shape that looks like the documentation
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-24 19:52:31 -05:00
Brian King 7a801184fa libata: Fixup n_elem initialization
Fixup the inialization of qc->n_elem. It currently gets
initialized to 1 for commands that do not transfer any data.
Fix this by initializing n_elem to 0 and only setting to 1
in ata_scsi_qc_new when there is data to transfer. This fixes
some problems seen with SATA devices attached to ipr adapters.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-24 02:04:34 -05:00
Tejun Heo 07c53dac49 ahci: don't enter slumber on power down
Some ATA/ATAPI devices act weirdly after the link is put into slumber
mode.  Some hang completely requiring physical power removal while
others fail to wake up till the link is hardreset a couple of times.

The addition of slumber on power down was never driven by real need.
It just followed what ahci spec said literally.  The spec itself seems
faulty in that it doesn't consider devices (not controllers) which
don't support link powersaving mode.

Theory never matches reality when it comes to dark allys of cheap
ATA/ATAPI world.  It's just unrealistic to expect vendors to test
rarely used link powersaving feature rigorously.  This patch makes
ahci more friendly to the coldness of reality.

This shouldn't have any negative effect - when suspend operation
succeeds, we power off the whole machine; otherwise, we wake up
everything.  I can't see any reason to be so elaborate with powering
down the link in the first place.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-01-24 02:03:45 -05:00