* Reorder ATA_DFLAG_* such that feature flags determined by
  ata_dev_configure() are on lower bits.  Reserve lower eight bits
  for this purpose and allocate dynamic flags from bit 8.

* Reorder ATA_FLAG_* such that feature flags determined during driver
  initiailization are on bits 0:15, dynamic flags on 16:23 and LLDD
  specific flags on 24:31.

* Kill trailing white space and lower-case an one line comment for
  consistency.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Kill unused flag ATA_FLAG_IN_EH.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Improve ata_bus_probe() such that configuration failures are handled
better.  Each device is given ATA_PROBE_MAX_TRIES chances, but any
non-transient error (revalidation failure with -ENODEV, configuration
failure with -EINVAL...) disables the device directly.  Any IO error
results in SATA PHY speed down and ata_set_mode() failure lowers
transfer mode.  The last try always puts a device into PIO-0.

After each failure, the whole port is reset to make sure that the
controller and all the devices are in a known and stable state.  The
reset also applies SATA SPD configuration if necessary.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

ap->sata_spd_limit contrains SATA PHY speed of the port.  It is
initialized to the configured value prior to probing thus preserving
BIOS configured value.  hardreset is responsible for applying SPD
limit and sata_std_hardreset() is updated to do that.  SATA SPD limit
will be used to enhance failure handling during probing and later by
EH.

This patch also normalizes some comments around affected code.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

For the time being we cannot use ata_dev_present() as it was renamed
to ata_dev_enabled() but we still need presence test.  Implement
negation of the test.  Conveniently, the negated result is needed in
more places.  This is suggested by Jeff Garzik.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch renames ata_dev_present() to ata_dev_enabled() and adds
ata_dev_disabled().  This is to discern the state where a device is
present but disabled from not-present state.  This disctinction is
necessary when configuring transfer mode because device selection
timing must not be violated even if a device fails to configure.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add a field to the host_set called 'flags' (was host_set_flags changed
to suit Jeff)
Add a simplex_claimed field so we can remember who owns the DMA channel
Add a ->mode_filter() hook to allow drivers to filter modes
Add docs for mode_filter and set_mode
Filter according to simplex state
Filter cable in core

This provides the needed framework to support all the mode rules found
in the PATA world. The simplex filter deals with 'to spec' simplex DMA
systems found in older chips. The cable filter avoids duplicating the
same rules in each chip driver with PATA. Finally the mode filter is
neccessary because drive/chip combinations have errata that forbid
certain modes with some drives or types of ATA object.

Drive speed setup remains per channel for now and the filters now use
the framework Tejun put into place which cleans them up a lot from the
older libata-pata patches.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Some hardware doesn't want the usual mode setup logic running. This
allows the hardware driver to replace it for special cases in the least
invasive way possible.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This is the minimal patch set to enable the current code to be used with
a controller following SFF (ie any PATA and early SATA controllers)
safely without crashes if there is no BMDMA area or if BMDMA is not
assigned by the BIOS for some reason.

Simplex status is recorded but not acted upon in this change, this isn't
a problem with the current drivers as none of them are for simplex
hardware. A following diff will deal with that.

The flags in the probe structure remain ->host_set_flags although Jeff
asked me to rename them, simply because the rename would break the usual
Linux rules that old code should break when there are changes. not
compile and run and then blow up/eat your computer/etc. Renaming this
later is a trivial exercise once a better name is chosen.
Signed-off-by: NJeff Garzik <jeff@garzik.org>

E.D.D. has no user in-tree and mostly useless.  Kill it.  For possible
out-of-tree users, add a nice warning message and error handling if
LLDD doesn't report any useable reset mechanism (and thus tries to use
E.D.D.).
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Remove some of the dependence on the host_set struct
in preparation for supporting SAS HBAs. Adds a struct device
pointer to the ata_port struct.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

At the moment libata doesn't pass pm_message_t down ata_device_suspend.
This causes drives to be powered down when we just want a freeze,
causing unnecessary wear and tear. This patch gets pm_message_t passed
down so that it can be used to determine whether to power down the
drive.
Signed-off-by: NNigel Cunningham <nigel@suspend2.net>

 drivers/scsi/libata-core.c |    5 +++--
 drivers/scsi/libata-scsi.c |    4 ++--
 drivers/scsi/scsi_sysfs.c  |    2 +-
 include/linux/libata.h     |    4 ++--
 include/scsi/scsi_host.h   |    2 +-
 5 files changed, 9 insertions(+), 8 deletions(-)
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add per-dev pio/mwdma/udma_mask.  All transfer mode limits used to be
applied to ap->*_mask which unnecessarily restricted other devices
sharing the port.  This change will also benefit later EH speed down
and hotplug.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add prototypes for stuff recently added by Alan.

Add some dummy noop functions for use by libata clients
that do not need to do anything. Future SAS patches will
utilize these functions.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

SCSI midlayer has moved hostt->eh_timed_out to transport template.  As
libata doesn't need full-blown transport support yet, implement
minimal transport for libata.  No transport class or whatsoever, just
empty transport template with ->eh_timed_out hook.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Add ATA_BITS_*, ATA_MASK_* macros and reorder xfer_mask fields such
that higher transfer mode is placed at higher order bit.  As thie
reordering breaks ata_mode_string(), this patch also rewrites
ata_mode_string().
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Rename ATA_FLAG_FLUSH_PIO_TASK to ATA_FLAG_FLUSH_PORT_TASK.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Kill unused pio_task and packet_task.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Implement port_task.  LLDD's can schedule a function to be executed
with context after specified delay.  libata core takes care of
synchronization against EH.  This is generalized form of pio_task and
packet_task which are tied to PIO hsm implementation.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

ata_dev_revalidate() re-reads IDENTIFY PAGE of the given device and
makes sure it's the same device as the configured one.  Once it's
verified that it's the same device, @dev is configured according to
newly read IDENTIFY PAGE.  Note that revalidation currently doesn't
invoke transfer mode reconfiguration.

Criteria for 'same device'

* same class (of course)
* same model string
* same serial string
* if ATA, same n_sectors (to catch geometry parameter changes)
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

ata_dev_config() needs to be done everytime a device is configured.
Fold it into ata_dev_configure().
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Convert dev->id from array to pointer.  This is to accomodate
revalidation.  During revalidation, both old and new IDENTIFY pages
should be accessible and single ->id array doesn't cut it.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Seperate out ata_class_present() from ata_dev_present().  This is
useful because new reset mechanism deals with classes[] directly.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch makes ata_for_each_sg() start with pad_sgent when
qc->n_elem is zero.  Previously, ata_for_each_sg() unconditionally
started with qc->__sg, handling the first sg to fill_sg() routines
even when the entry was invalid.  And while at it, unwind ?: in
ata_qc_next_sg() into if statement.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

This patch renames ata_dev_id_[c_]string() to ata_id_[c_]string().
All other functions which read data from ATA ID data start with ata_id
and those two function names were getting too long.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

If a low level driver wants to control max_sectors, it had to adjust
ap->host->max_sectors and set ATA_DFLAG_LOCK_SECTORS to tell
ata_scsi_slave_config not to override the limit.  This is not only
cumbersome but also incorrect for hosts which support more than one
devices per port.

This patch adds per-device ->max_sectors.  If the field is unset
(zero), libata core layer will adjust ->max_sectors according to
default rules.  If the field is set, libata honors the setting.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

cdb_len is per-device property.  Sharing cdb_len on ap results in
inaccurate configuration on revalidation and hotplugging.  This patch
makes cdb_len per-device.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

ata_dev_id_c_string() reads ATA string from the specified offset of
the given IDENTIFY PAGE and puts it in the specified buffer in trimmed
and NULL-terminated form.  The caller must supply a buffer which is
one byte larger than the maximum size of the target ID string.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

libata assert() now has no user left.  Kill it.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

This patch inlines ata_qc_complete() and uninlines __ata_qc_complete()
as suggested by Jeff Garzik.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

Implement ata_scsi_timed_out(), to be used as
scsi_host_template->eh_timed_out callback for all libata drivers.
Without this function, the following race exists.

If a qc completes after SCSI timer expires but before libata EH kicks
in, the qc gets completed but the scsicmd still gets passed to libata
EH resulting in ->eng_timeout invocation with NULL qc, which none is
handling properly.

This patch makes sure that scmd and qc share the same lifetime.
Original idea from Jeff Garzik <jgarzik@pobox.com>.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

Add ATA_QCFLAG_EH_SCHEDULED.  If this flag is set, the qc is owned by
EH and normal completion path is not allowed to finish it.  This patch
doesn't actually use this flag.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

This patch implements the off-the-shelf probeinit component operation.
Currently, all it does is waking up the PHY if it's a SATA port.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

This patch adds probeinit component operation to
ata_drive_probe_reset().  If present, this new operation is called
before performing any reset.  The operations's roll is to prepare @ap
for following probe-reset operations.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

This patch makes sure that pio tasks are flushed before proceeding
with EH.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

ATA_FLAG_IN_EH flag is set on entry to EH and cleared on completion.
This patch just sets and clears the flag.  Following patches will
build normal qc execution / EH synchronization aroung this flag.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

Implement SRST, COMRESET and standard postreset component operations
for ata_drive_probe_reset(), and use these three functions to
implement ata_std_probe_reset.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

Most low level drivers share supported reset/classify actions and
sequence.  This patch implements ata_drive_probe_reset() which helps
constructing ->probe_reset from three component operations -
softreset, hardreset and postreset.  This minimizes duplicate code and
yet allows flexibility if needed. The three component operations can
also be shared by EH later.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>