Commit Graph

464 Commits

Author SHA1 Message Date
Patrick Mochel
5d9464a469 ACPI: add ACPI bus_type for driver model
Add ACPI bus_type for Linux driver model.

1.	.shutdown method is added into acpi_driver.ops
	needed by bus_type operations.
2.	remove useless parameter 'int state' in .resume method.
3.	change parameter 'int state'
	to 'pm_message_t state' in .suspend method.

Note:	The new .uevent method mark ACPI drivers by PNPID instead of by name.
	Udev script needs to look for "HWID=" or "COMPTID=" to load
	ACPI drivers as a result.

Signed-off-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-12-15 23:38:34 -05:00
Patrick Mochel
d43ec68e98 ACPI: add device_driver and hepler functions
Add device_driver into acpi_driver for driver model.
Add helper functions 'to_acpi_device' and 'to_acpi_driver'
to get structure acpi_device/acpi_driver by device/device_driver.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-12-15 23:38:34 -05:00
Zhang Rui
1d268b0a0f ACPI: rename some functions
We want the name 'to_acpi_device'.
And the current macro 'to_acpi_device' will be removed
after device model is setup.
So just simply rename them.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-12-15 23:38:34 -05:00
Zhang Rui
9e89dde2b0 ACPI: clean up scan.c
Adjust the code and make code doing similar things together.
No logic changes.

Signed-off-by : Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-12-15 23:38:34 -05:00
David Howells
9db7372445 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	drivers/ata/libata-scsi.c
	include/linux/libata.h

Futher merge of Linus's head and compilation fixups.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-12-05 17:01:28 +00:00
David Howells
4c1ac1b491 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	drivers/infiniband/core/iwcm.c
	drivers/net/chelsio/cxgb2.c
	drivers/net/wireless/bcm43xx/bcm43xx_main.c
	drivers/net/wireless/prism54/islpci_eth.c
	drivers/usb/core/hub.h
	drivers/usb/input/hid-core.c
	net/core/netpoll.c

Fix up merge failures with Linus's head and fix new compilation failures.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-12-05 14:37:56 +00:00
Al Viro
914e26379d [PATCH] severing fs.h, radix-tree.h -> sched.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-12-04 02:00:24 -05:00
Benjamin Herrenschmidt
465ae641e4 ACPI: Change ACPI to use dev_archdata instead of firmware_data
Change ACPI to use dev_archdata instead of firmware_data

This patch changes ACPI to use the new dev_archdata on i386, x86_64
and ia64 (is there any other arch using ACPI ?) to store it's
acpi_handle.

It also removes the firmware_data field from struct device as this
was the only user.

Only build-tested on x86

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:52:01 -08:00
Dave Jones
0916bd3ebb [PATCH] Correct bound checking from the value returned from _PPC method.
processor_perflib.c::acpi_processor_ppc_notifier() check if the value
returned by the processor's _PPC method is 0 and return failed if so.
This is wrong since 0 indicate that the bios think the processor can go
to the highest frequency.  This patch for example fix the HP NX 6125 to
allow its highest frequency to be available.

Signed-off-by: Bruno Ducrot <ducrot@poupinou.org>
Cc: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-23 09:18:55 -08:00
David Howells
65f27f3844 WorkStruct: Pass the work_struct pointer instead of context data
Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.

For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.

To make this work, an extra flag is introduced into the management side of the
work_struct.  This governs auto-release of the structure upon execution.

Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function.  This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated..  This is a
problem if the auxiliary data is taken away (as done by the last patch).

However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems.  But then the work function must itself release the
work_struct by calling work_release().

In most cases, automatic release is fine, so this is the default.  Special
initiators exist for the non-auto-release case (ending in _NAR).


Signed-Off-By: David Howells <dhowells@redhat.com>
2006-11-22 14:55:48 +00:00
Linus Torvalds
b976fe19ac Revert "ACPI: created a dedicated workqueue for notify() execution"
This reverts commit 37605a6900.

Again.

This same bug has now been introduced twice: it was done earlier by
commit b8d35192c5, only to be reverted
last time in commit 72945b2b90.

We must NOT try to queue up notify handlers to another thread than the
normal ACPI execution thread, because the notifications on some systems
seem to just keep on accumulating until we run out of memory and/or
threads.

Keeping events within the one deferred execution thread automatically
throttles the events properly.

At least the Compaq N620c will lock up completely on the first thermal
event without this patch reverted.

Cc: David Brownell <david-b@pacbell.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Alexey Starikovskiy <alexey.y.starikovskiy@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-17 19:31:09 -08:00
Yasunori Goto
887b95931b [PATCH] acpi memory hotplug: remove strange add_memory fail message
I wrote a patch to avoid redundant memory hot-add call at boot time.  This
was cause of strange fail message of memory hotplug like "ACPI: add_memory
failed".  Memory is recognized by early boot code with EFI/E820.

But, if DSDT describes memory devices for them, then hot-add code is called
for already recognized memory, and it shows fail messages with -EEXIST.
So, sys admin will misunderstand this message as something wrong by it.

This patch avoids them by preventing redundant hot-add call until
completion of driver initialization.

[akpm@osdl.org: cleanups]
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:38 -07:00
Yasunori Goto
6cbe44cd8d [PATCH] Change log level of a message of acpi_memhotplug to KERN_DEBUG
I suppose this message seems quite useless except debugging.  It just shows
"Hotplug Mem Device".  System admin can't know anything by this message.
So, I would like to change it to KERN_DEBUG.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:37 -07:00
Darrick J. Wong
c5a114f1fb [PATCH] fix "ACPI: Processor native C-states using MWAIT"
This patch breaks C-state discovery on my IBM IntelliStation Z30 because
the return value of acpi_processor_get_power_info_fadt is not assigned to
"result" in the case that acpi_processor_get_power_info_cst returns
-ENODEV.  Thus, if ACPI provides C-state data via the FADT and not _CST (as
is the case on this machine), we incorrectly exit the function with -ENODEV
after reading the FADT.  The attached patch sets the value of result so
that we don't exit early.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Acked-by: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
Acked-by: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:37 -07:00
Andrew Morton
1fec74a9cd [PATCH] acpi_processor_latency_notifier(): UP warning fix
drivers/acpi/processor_idle.c:1112: warning: 'smp_callback' defined but not used

Cc: Len Brown <lenb@kernel.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17 08:18:44 -07:00
Len Brown
9aaed2b42d Pull trivial into test branch 2006-10-14 02:28:07 -04:00
Len Brown
384bc8f070 Pull bugzilla-5534 into test branch 2006-10-14 02:26:42 -04:00
Len Brown
ed3269a31b Pull ec into test branch 2006-10-14 02:26:10 -04:00
Len Brown
d7321ad293 Pull mwait into test branch 2006-10-14 02:25:59 -04:00
Len Brown
1d5b30fc33 Pull battery into test branch 2006-10-14 02:25:48 -04:00
Len Brown
c92fd49c54 Pull ibm into test branch 2006-10-14 02:25:40 -04:00
Len Brown
9443d7c934 Pull asus into test branch 2006-10-14 02:25:33 -04:00
Jiri Kosina
34c4415ab8 ACPI: check battery status on resume for un/plug events during sleep
Add ->resume method to the ACPI battery handler to check
if the battery state has changed during sleep.
If yes, update the ACPI internal data structures
for benefit of /proc/acpi/battery/.

Signed-off-by: Jiri Kosina <jikos@jikos.cz>
Cc: Stefan Seyfried <seife@suse.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 02:22:51 -04:00
Eiichiro Oiwa
aeb1104814 ACPICA: Fix incorrect handling of PCI Express Root Bridge _HID
I could not get correct PCI Express bus number from the structure of
acpi_object_extra. I always get zero as bus number regardless of bus
location. I found that there is incorrect comparison with _HID (PNP0A08) in
acpi/events/evrgnini.c and PCI Express _BBN method always fail.
Therefore, we always get zero as PCI Express bus number.
http://bugzilla.kernel.org/show_bug.cgi?id=7145

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 02:13:38 -04:00
Alexey Dobriyan
6df05702f9 ACPI: asus_acpi: don't printk on writing garbage to proc files
This reporting is useless (we errno anyway).

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 02:03:49 -04:00
Darren Jenkins
6311f0dac0 ACPI: asus_acpi: fix proc files parsing
ICC complains about a "Pointless comparsion of unsigned interger with zero"
@ line 760 & 808 of asus_acpi.c

parse_arg() mentioned below returns -E but it's copied into unsigned variable...

Signed-off-by: Darren Jenkins <darrenrjenkins@gmail.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 02:03:02 -04:00
Randy Dunlap
a790b323fb ACPI: fix printk format warnings
Fix printk format warnings in drivers/acpi:
drivers/acpi/tables/tbget.c:326: warning: format '%X' expects type 'unsigned int', but argument 5 has type 'long unsigned int'
drivers/acpi/tables/tbrsdt.c:189: warning: format '%X' expects type 'unsigned int', but argument 5 has type 'long unsigned int'

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 01:59:46 -04:00
Pierre Ossman
7af8b66004 ACPI: fix section for CPU init functions
The ACPI processor init functions should be marked as __cpuinit as they use
structures marked with __cpuinitdata.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 01:58:38 -04:00
Len Brown
f4d2e2d87e ACPI: update comments in motherboard.c
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 01:56:27 -04:00
Jiri Kosina
168a328f30 ACPI: acpi_pci_link_set() can allocate with either GFP_ATOMIC or GFP_KERNEL
acpi_pci_link_set() allocates both with interrupts on
and with interrupts off (resume-time), so check interrupts
and decide on GFP_ATOMIC or GFP_KERNEL at run-time.

Signed-off-by: Jiri Kosina <jikos@jikos.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 01:54:21 -04:00
Dmitry Torokhov
786f18c666 ACPI: fix potential OOPS in power driver with CONFIG_ACPI_DEBUG
device was set to null and used before set in a debug printk

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 01:54:21 -04:00
Alexey Y. Starikovskiy
37605a6900 ACPI: created a dedicated workqueue for notify() execution
http://bugzilla.kernel.org/show_bug.cgi?id=5534#c160

Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 01:50:10 -04:00
Alexey Y. Starikovskiy
fcfc638c6b ACPI: Remove deferred execution from global lock acquire wakeup path
On acquiring the ACPI global lock, if there were sleepers on the lock,
we used to use acpi_os_execute() to defer a thread which would signal
sleepers.  Now just signal the semaphore directly.

http://bugzilla.kernel.org/show_bug.cgi?id=5534#c159

Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 01:50:09 -04:00
Lennart Poettering
ab9e43c640 ACPI: EC: export ec_transaction() for msi-laptop driver
Signed-off-by: Lennart Poettering <mzxreary@0pointer.de>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:49:56 -04:00
Denis M. Sadykov
6ffb221a82 ACPI: EC: Simplify acpi_hw_low_level*() with inb()/outb().
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>
2006-10-14 00:49:56 -04:00
Denis M. Sadykov
8e0341ba79 ACPI: EC: Unify poll and interrupt gpe handlers
Signed-off-by: Alexey Y. Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:49:55 -04:00
Denis M. Sadykov
3576cf619b ACPI: EC: Unify poll and interrupt mode transaction functions
Signed-off-by: Alexey Y. Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:49:55 -04:00
Denis M. Sadykov
703959d47e ACPI: EC: Remove unused variables and duplicated code
Signed-off-by: Alexey Y. Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:49:54 -04:00
Denis M. Sadykov
7c6db5e512 ACPI: EC: Remove unnecessary delay added by previous transation patch.
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>
2006-10-14 00:49:53 -04:00
Lennart Poettering
d7a76e4cb3 ACPI: consolidate functions in acpi ec driver
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>
2006-10-14 00:49:52 -04:00
Venkatesh Pallipadi
991528d734 ACPI: Processor native C-states using MWAIT
Intel processors starting with the Core Duo support
support processor native C-state using the MWAIT instruction.
Refer: Intel Architecture Software Developer's Manual
http://www.intel.com/design/Pentium4/manuals/253668.htm

Platform firmware exports the support for Native C-state to OS using
ACPI _PDC and _CST methods.
Refer: Intel Processor Vendor-Specific ACPI: Interface Specification
http://www.intel.com/technology/iapc/acpi/downloads/302223.htm

With Processor Native C-state, we use 'MWAIT' instruction on the processor
to enter different C-states (C1, C2, C3).  We won't use the special IO
ports to enter C-state and no SMM mode etc required to enter C-state.
Overall this will mean better C-state support.

One major advantage of using MWAIT for all C-states is, with this and
"treat interrupt as break event" feature of MWAIT, we can now get accurate
timing for the time spent in C1, C2, ..  states.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:35:39 -04:00
Lebedev, Vladimir P
3cd5b87d96 ACPI: sbs: fix module_param() initializers
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:34:00 -04:00
Lebedev, Vladimir P
963497c12a ACPI: sbs: check for NULL device pointer
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:33:52 -04:00
Stefan Schmidt
4d6bd5ea4e ACPI: ibm_acpi: Remove experimental status for brightness and volume.
The brightness and volume features from ibm-acpi are stable.
The experimental flag is no longer needed.

Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Borislav Deianov <borislav@users.sourceforge.net>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:32:22 -04:00
Marek W
288f3ad406 ACPI: asus_acpi: W3000 support
Add support for W3000 (W3V) and indirectly fixes an issue with kmilo under KDE
(it was triggering excessive LCD read error messages by querying asus_acpi
module) allowing people (I am probably the only one who tested this) with
W3000 to run kmilo.

Cc: Karol Kozimor <sziwan@hell.org.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2006-10-14 00:27:06 -04:00
Linus Torvalds
53a5fbdc2d ACPI: Allow setting SCI_EN bit in PM1_CONTROL register
This is needed by at least the Mac Mini's, which (incorrectly) come back
from suspend with SCI_EN clear.

Thanks to Frédéric Riss for hunting this down.

Acked-by: Frédéric Riss <frederic.riss@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-10 17:14:44 -07:00
Al Viro
4370df9782 [PATCH] acpi NULL noise removal
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-10 15:37:22 -07:00
David Howells
7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00
Matt LaPlante
c73a668c09 fix drivers/acpi/Kconfig typos
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:24:43 +02:00
Arjan van de Ven
5c87579e65 [PATCH] maximum latency tracking infrastructure
Add infrastructure to track "maximum allowable latency" for power saving
policies.

The reason for adding this infrastructure is that power management in the
idle loop needs to make a tradeoff between latency and power savings
(deeper power save modes have a longer latency to running code again).  The
code that today makes this tradeoff just does a rather simple algorithm;
however this is not good enough: There are devices and use cases where a
lower latency is required than that the higher power saving states provide.
 An example would be audio playback, but another example is the ipw2100
wireless driver that right now has a very direct and ugly acpi hook to
disable some higher power states randomly when it gets certain types of
error.

The proposed solution is to have an interface where drivers can

* announce the maximum latency (in microseconds) that they can deal with
* modify this latency
* give up their constraint

and a function where the code that decides on power saving strategy can
query the current global desired maximum.

This patch has a user of each side: on the consumer side, ACPI is patched
to use this, on the producer side the ipw2100 driver is patched.

A generic maximum latency is also registered of 2 timer ticks (more and you
lose accurate time tracking after all).

While the existing users of the patch are x86 specific, the infrastructure
is not.  I'd like to ask the arch maintainers of other architectures if the
infrastructure is generic enough for their use (assuming the architecture
has such a tradeoff as concept at all), and the sound/multimedia driver
owners to look at the driver facing API to see if this is something they
can use.

[akpm@osdl.org: cleanups]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jesse.barnes@intel.com>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:19 -07:00