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>
Delay the read of the EC status register until
after the event that caused it occurs -- otherwise
it is possible to read and act on stale status that was
associated with the previous event.
Do this with a perpetually incrementing "event_count" to detect
when a new event occurs and it is safe to read status.
There is no workaround for polling mode -- it is inherently
exposed to reading and acting on stale status, since it
doesn't have an interrupt to tell it the event completed.
http://bugzilla.kernel.org/show_bug.cgi?id=8110
Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
It was erroneously used as a description rather than a name.
ie. turn this:
lenb@se7525gp2:/sys> ls bus/acpi/drivers
ACPI AC Adapter Driver ACPI Embedded Controller Driver ACPI Power Resource Driver
ACPI Battery Driver ACPI Fan Driver ACPI Processor Driver
ACPI Button Driver ACPI PCI Interrupt Link Driver ACPI Thermal Zone Driver
ACPI container driver ACPI PCI Root Bridge Driver hpet
into this:
lenb@se7525gp2:~> ls /sys/bus/acpi/drivers
ac battery button container ec fan hpet pci_link pci_root power processor thermal
Signed-off-by: Len Brown <len.brown@intel.com>
cosmetic only
Make "module name" actually match the file name.
Invoke with ';' as leaving it off confuses Lindent and gcc doesn't care.
Fix indentation where Lindent did get confused.
Signed-off-by: Len Brown <len.brown@intel.com>
The recent EC cleanup left a printk enabled on handler evaluation
resulting in a bunch of messages on normal operation, like so:
ACPI: EC: evaluating _Q60
Signed-off-by: Len Brown <len.brown@intel.com>
Fix sparse warning:
drivers/acpi/ec.c:372:12: warning: function 'ec_transaction' with external linkage has definition
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Simplify acpi_hw_low_level_xxx() functions to inb() and outb().
Signed-off-by: Alexey Y. Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Remove unnecessary delay (50 ms) while reading data from EC in interrupt mode.
Signed-off-by: Alexey Y. Starikovskiy <alexey.y.starikovskiy@intel.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>
