Implement _GTF command filtering which can be controlled by
libata.acpi_filter kernel parameter.  Currently SETXFER and LOCK
commands are filtered.

libata configures transfer mode by itself and _GTF SETXFER commands
can potentially disrupt device configuration.  _GTM/_STM mechanism
can't handle hotplugging too well and when _GTF is executed,
controller is in PIO0 rather than the mode _STM configured.

Note that detecting SET MAX LOCK requires looking at the previous
command.  This adds a bit to code complexity.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

As _GTF commands can't transfer data, device error never signals
transfer error.  It indicates that the device vetoed the operation, so
it's meaningless to retry.

This patch makes libata-acpi to report and continue on device errors
when executing _GTF commands.  Also commands rejected by device don't
contribute to the number of _GTF commands executed.

While at it, update _GTF execution reporting such that all successful
commands are logged at KERN_DEBUG and rename taskfile_load_raw() to
ata_acpi_run_tf() for consistency.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

* If _GTF evalution fails, it's pointless to retry.  If nothing else
  is wrong, just ignore the error.

* After disabling ACPI, return success iff the number of executed _GTF
  command equals zero.  Otherwise, tell EH to retry.  This change
  fixes bogus 1 return bug where ata_acpi_on_devcfg() expects the
  caller to reload IDENTIFY data and continue but the caller
  interprets it as an error.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

On certain implementations, _GTF evaluation depends on preceding _STM
and both can be pretty picky about the configuration.  Using _GTM
result cached during controller initialization satisfies the most
neurotic _STM implementation.  However, libata evaluates _GTF after
reset during device configuration and the hardware state can be
different from what _GTF expects and can cause evaluation failure.

This patch adds dev->gtf_cache and updates ata_dev_get_GTF() such that
it uses the cached value if available.  Cache is cleared with a call
to ata_acpi_clear_gtf().

Because for SATA ACPI nodes _GTF must be evaluated after _SDD which
can't be done till IDENTIFY is complete, _GTF caching from
ata_acpi_on_resume() is used only for IDE ACPI nodes.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

_GTM fetches currently configured transfer mode while _STM configures
controller according to _GTM parameter and prepares transfer mode
configuration TFs for _GTF.  In many cases _GTM and _STM
implementations are quite brittle and can't cope with configuration
changed by libata.

libata does not depend on ATA ACPI to configure devices.  The only
reason libata performs _GTM and _STM are to make _GTF evaluation
succeed and libata also doesn't care about how _GTF TFs configure
transfer mode.  It overrides that configuration anyway, so from
libata's POV, it doesn't matter what value is feeded to _STM as long
as evaluation succeeds for _STM and following _GTF.

This patch adds dev->__acpi_init_gtm and store initial _GTM values on
host initialization before modified by reset and mode configuration.
If the field is valid, ata_acpi_init_gtm() returns pointer to the
saved _GTM structure; otherwise, NULL.

This saved value is used for _STM during resume and peek at
BIOS/firmware programmed initial timing for later use.  The accessor
is there to make building w/o ACPI easy as dev->__acpi_init doesn't
exist if ACPI is not enabled.

On driver detach, the initial BIOS configuration is restored by
executing _STM with the initial _GTM values such that the next driver
can also use the initial BIOS configured values.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add two hooks - ata_acpi_dissociate() which is called during driver
detach after the whole host is shutdown and ata_acpi_on_disable()
which is called when a device is disabled.
Signed-off-by: NTejun heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

* No internal function uses const ata_port.  Drop const from @ap.

* Make ata_acpi_stm() copy @stm before using it and change @stm to
  const.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Experience suggests that the _GTF method may be bad. We currently fail
device revalidation in that case, which seems excessive.
Signed-off-by: NMatthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Tackle the relatively sane complaints of checkpatch --file.

The vast majority is indentation and whitespace changes, the rest are

* #include fixes
* printk KERN_xxx prefix addition
* BSS/initializer cleanups
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Add @timeout argument to ata_exec_internal[_sg]().  If 0, default
timeout ata_probe_timeout is used.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Talk to the dark side our driver has to, yes. Much misleading is the
data. Store it in a structure we do so that it may be parsed.
Signed-off-by: NAlan Cox <alan@redhat.com>
--
Whats small, old and shouts phrases out of order across mountains ?
Yodla..
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Modern laptops with hotswap bays still tend to utilise a PATA interface
on a SATA bridge, generally with the host controller in some legacy
emulation mode rather than AHCI. This means that the existing hotplug
code in libata is unable to work. The ACPI specification states that
these devices can send notifications when hotswapped, which avoids the
need to obtain notification from the controller. This patch uses the
existing libata-acpi code and simply registers a notification in order
to trigger a rescan whenever the firmware signals an event.
Signed-off-by: NMatthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Extend ata_acpi_associate_sata_port() such that it can handle PMP and
call it when PMP is attached and detached.

Build breakage when !CONFIG_ATA_ACPI was spotted and fixed by Petr
Vandrovec.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Combined from two Alan Cox patches:

1) libata: ACPI checks for 80wire cable

We can use the ACPI mode information with several drivers as a hint to
cable type. If the ACPI mode set by the BIOS is faster than UDMA33 then
we know the BIOS thinks there are 80wire cables. If it doesn't set such a
mode or it has no ACPI method then we get no further information and can
rely on existing approaches

Introduce the function headers needed. Null it out for non ACPI boxes
Signed-off-by: NAlan Cox <alan@redhat.com>

2) libata: ACPI checks for 80wire cable

Provide actual methods for checking if the ACPI support thinks the cable
is 80wire, or doesn't know
Signed-off-by: NAlan Cox <alan@redhat.com>

Combined into a single changeset and
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Multiple links and different number of devices per link should be
considered to iterate over links and devices.  This patch implements
and uses link and device iterators - ata_port_for_each_link() and
ata_link_for_each_dev() - and ata_link_max_devices().

This change makes a lot of functions iterate over only possible
devices instead of from dev 0 to dev ATA_MAX_DEVICES.  All such
changes have been examined and nothing should be broken.

While at it, add a separating comment before device helpers to
distinguish them better from link helpers and others.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Introduce ata_link.  It abstracts PHY and sits between ata_port and
ata_device.  This new level of abstraction is necessary to support
SATA Port Multiplier, which basically adds a bunch of links (PHYs) to
a ATA host port.  Fields related to command execution, spd_limit and
EH are per-link and thus moved to ata_link.

This patch only defines the host link.  Multiple link handling will be
added later.  Also, a lot of ap->link derefences are added but many of
them will be removed as each part is converted to deal directly with
ata_link instead of ata_port.

This patch introduces no behavior change.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Implement _GTM/_STM support.  acpi_gtm is added to ata_port which
stores _GTM parameters over suspend/resume cycle.  A new hook
ata_acpi_on_suspend() is responsible for storing _GTM parameters
during suspend.  _STM is executed in ata_acpi_on_resume().  With this
change, invoking _GTF is safe on IDE hierarchy and acpi_sata check
before _GTF is removed.

ata_acpi_gtm() and ata_acpi_stm() implementation is taken from Alan
Cox's pata_acpi implementation.  ata_acpi_gtm() is fixed such that the
result parameter is not shifted by sizeof(union acpi_object).
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Remove remaining unnecessary feature and status checks.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch reimplements ACPI invocation such that, instead of
exporting ACPI details to the rest of libata, ACPI event handlers -
ata_acpi_on_resume() and ata_acpi_on_devcfg() - are used.  These two
functions are responsible for determining whether specific ACPI method
is used and when.

On resume, _GTF is scheduled by setting ATA_DFLAG_ACPI_PENDING device
flag.  This is done this way to avoid performing the action on wrong
device device (device swapping while suspended).

On every ata_dev_configure(), ata_acpi_on_devcfg() is called, which
performs _SDD and _GTF.  _GTF is performed only after resuming and, if
SATA, hardreset as the ACPI spec specifies.  As _GTF may contain
arbitrary commands, IDENTIFY page is re-read after _GTF taskfiles are
executed.

If one of ACPI methods fails, ata_acpi_on_devcfg() retries on the
first failure.  If it fails again on the second try, ACPI is disabled
on the device.  Note that successful configuration clears ACPI failed
status.

With all feature checks moved to the above two functions,
do_drive_set_taskfiles() is trivial and thus collapsed into
ata_acpi_exec_tfs(), which is now static and converted to return the
number of executed taskfiles to be used by ata_acpi_on_resume().  As
failures are handled properly, ata_acpi_push_id() now returns -errno
on errors instead of unconditional zero.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

* Add missing LOCKING: and RETURNS: to function comment.

* Don't conditionalize warning messages with ata_msg_probe().  Print
  directly with KERN_WARNING.

* Drop duplicate debug messages.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch cleans up ata_acpi_exec_tfs() and its friends.

* Rename taskfile_array to ata_acpi_gtf and make it __packed as it's
  used as argument to ACPI method, and use pointer to ata_acpi_gtf and
  number of taskfiles to represent _GTF taskfiles instead of a pointer
  casted into unsigned long and byte count.  This makes argument
  re-checking in do_drive_set_taskfiles() unnecessary.

* Pointer in void * not in unsigned long.

* Clean up do_drive_get_GTF() error handling and make
  do_drive_get_GTF() return number of taskfiles on success, 0 if _GTF
  doesn't exist or doesn't contain valid ata.  -errno on other errors.

* Remove superflous check for acpi->buffer.pointer.

* Update taskfile_load_raw() such that printed messages look similar
  to the messages printed by ata_eh_report().

* s/do_drive_get_GTF/ata_dev_get_GTF/
  s/do_drive_set_taskfiles/ata_dev_set_taskfiles/
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

* Add acpi_handle to ata_host and ata_port.  Rename
  ata_device->obj_handle to ->acpi_handle and move it above such that
  it doesn't get cleared on reconfiguration.

* Replace ACPI node association which ata_acpi_associate() which is
  called once during host initialization.  Unlike the previous
  implementation, ata_acpi_associate() uses ATA_FLAG_ACPI_SATA to
  choose between IDE or SATA ACPI hierarchy and uses simple child look
  up instead of recursive walk to match the nodes.  This is way safer
  and simpler.  Please read the following message for more info.

  http://article.gmane.org/gmane.linux.ide/17554Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Whether a controller needs IDE or SATA ACPI hierarchy is determined by
the programming interface of the controller not by whether the
controller is SATA or PATA, or it supports slave device or not.  This
patch adds ATA_FLAG_ACPI_SATA port flags which tells libata-acpi that
the port needs SATA ACPI nodes, and sets the flag for ahci and
sata_sil24.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch cleans up libata-acpi such that it looks similar to other
libata files.  This patch doesn't introuce any behavior changes.

* make libata-acpi functions take ata_device instead of ata_port +
  device index
* s/atadev/dev/
* de-indent local variable declarations
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

_GTF command is never ATA_PROT_ATAPI_NODATA whether the device is
ATAPI or not.  It's always ATA_PROT_NODATA.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Not yet ready to turn on ATA ACPI by default, for either PATA or SATA.

Also, rename the global-scope module parameter variable 'noacpi' to
something more libata-specific, reducing the potential for namespace
collision.
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The ACPI specification states, and BIOS implementations depend on,
_STM being called before _GTF.

SATA does this, but PATA does not.  So for now, simply
prevent execution of _GTF on PATA devices.  Longer term we
should implement ACPI support for PATA devices in libata.
Signed-off-by: NKristen Accardi <kristen.c.accardi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

For 2.6.20 it mostly used to just not work, for 2.6.21-rc it crashes, this
seems to be down to luck (bad or good). The libata-acpi code needs to
avoid doing PCI work on non-PCI devices. This is one hack although it's
not pretty and perhaps there is a "right" way to check if a struct device
* is PCI ?
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

All drivers must implement this hook, otherwise ATA commands would go
nowhere (and a lot of other oopsen would appear as well).
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Merge order left libata-acpi and pata_scc with remainling usage of
ap->id.  Kill superflous id printing and substitute the remaining ones
with ap->print_id.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

I have reproduced the AE_AML_BUFFER_LIMIT exception mentioned in
<http://bugzilla.kernel.org/show_bug.cgi?id=7689> basing on the SSDT ASL
code and libata ata_acpi_push_id() code.  There is an oversight in
ata_acpi_push_id() causing the exception.  The following update fixes it:
Signed-off-by: NFiodor Suietov <fiodor.f.suietov@intel.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

_SDD (Set Device Data) is an ACPI method that is used to tell the
firmware what the identify data is of the device that is attached to
the port.  It is an optional method, and it's ok for it to be missing.
Because of this, we always return success from the routine that calls
this method, even if the execution fails.
Signed-off-by: NKristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
(cherry picked from 39aa79e0a1f5f2e28aa341f035940746a98b45b1 commit)

_GTF is an acpi method that is used to reinitialize the drive.  It returns
a task file containing ata commands that are sent back to the drive to restore
it to boot up defaults.
Signed-off-by: NKristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
(cherry picked from 9c69cab24b51a89664f4c0dfaf8a436d32117624 commit)