The ACPI EC that is used in MSI laptops knows some non-standard
commands for changing the screen brighntess and a few other things,
which are used by the msi-laptop.c driver. Unfortunately for these
commands no GPE events for IBF and OBF are triggered. Since nowadays
the EC code uses the ec_intr=1 mode by default, this causes these
operations to timeout, although they don't fail. In result, all
operations that you can do with the msi-laptop.c driver take more or
less 1s to complete, which is awfully slow.

In one of the more recent kernels (2.6.20?) the EC subsystem has been
revamped. With that change the EC timeout has been increased. before
that increase the MSI EC accesses were slow -- but not *that* slow,
hence I took notice of this limitation of the MSI EC hardware only very
recently.

The standard EC operations on the MSI EC as defined in the ACPI spec
support GPE events properly.

The following patch adds a new argument "force_poll" to the
ec_transaction() function (and friends). If set to 1, the function
will poll for IBF/OBF even if ec_intr=1 is enabled. If set to 0 the
current behaviour is used. The msi-laptop driver is modified to make
use of this new flag, so that OBF/IBF is polled for the special MSI EC
transactions -- but only for them.

Signed-off-by: Lennart Poettering <mzxreary@0pointer.de>
Acked-by: Alexey Starikovskiy <aystarik@gmail.com>
Signed-off-by: Len Brown <len.brown@intel.com>

acpi_table_parse_madt_family() is also used to parse SRAT entries.
So re-name it to acpi_table_parse_entries(), and re-name the
madt-specific variables within it accordingly.

cosmetic only.

Signed-off-by: Len Brown <len.brown@intel.com>

acpi_madt_entry_handler() is also used for the SRAT,
so re-name it acpi_table_entry_handler().

cosmetic only.

Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Len Brown <len.brown@intel.com>

Provide ACPI _PRT support for SN Altix systems.

The SN Altix platform does not conform to the
IOSAPIC IRQ routing model, so a new acpi_irq_model
(ACPI_IRQ_MODEL_PLATFORM) has been defined. The SN
platform specific code sets acpi_irq_model to
this new value, and keys off of it in acpi_register_gsi()
to avoid the iosapic code path.

Signed-off-by: John Keller <jpk@sgi.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Unify the following functions:

    acpi_ec_poll_read()
    acpi_ec_poll_write()
    acpi_ec_poll_query()
    acpi_ec_intr_read()
    acpi_ec_intr_write()
    acpi_ec_intr_query()

into:

    acpi_ec_poll_transaction()
    acpi_ec_intr_transaction()

These new functions take as arguments an ACPI EC command, a few bytes
to write to the EC data register and a buffer for a few bytes to read
from the EC data register. The old _read(), _write(), _query() are
just special cases of these functions.

Then unified the code in acpi_ec_poll_transaction() and
acpi_ec_intr_transaction() a little more. Both functions are now just
wrappers around the new acpi_ec_transaction_unlocked() function. The
latter contains the EC access logic, the two original
function now just do their special way of locking and call the the
new function for the actual work.

This saves a lot of very similar code. The primary reason for doing
this, however, is that my driver for MSI 270 laptops needs to issue
some non-standard EC commands in a safe way. Due to this I added a new
exported function similar to ec_write()/ec_write() which is called
ec_transaction() and is essentially just a wrapper around
acpi_ec_{poll,intr}_transaction().

Signed-off-by: Lennart Poettering <mzxreary@0pointer.de>
Acked-by: Luming Yu <luming.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>