kernel/git/stable/linux.git/drivers/acpi/power.c, branch linux-3.18.y

ACPI: power: Skip duplicate power resource references in _PRx

2019-01-26T08:44:24+00:00

commit 7d7b467cb95bf29597b417d4990160d4ea6d69b9 upstream. Some ACPI tables contain duplicate power resource references like this: Name (_PR0, Package (0x04) // _PR0: Power Resources for D0 { P28P, P18P, P18P, CLK4 }) This causes a WARN_ON in sysfs_add_link_to_group() because we end up adding a link to the same acpi_device twice: sysfs: cannot create duplicate filename '/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/808622C1:00/OVTI2680:00/power_resources_D0/LNXPOWER:0a' CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.12-301.fc29.x86_64 #1 Hardware name: Insyde CherryTrail/Type2 - Board Product Name, BIOS jumperx.T87.KFBNEEA02 04/13/2016 Call Trace: dump_stack+0x5c/0x80 sysfs_warn_dup.cold.3+0x17/0x2a sysfs_do_create_link_sd.isra.2+0xa9/0xb0 sysfs_add_link_to_group+0x30/0x50 acpi_power_expose_list+0x74/0xa0 acpi_power_add_remove_device+0x50/0xa0 acpi_add_single_object+0x26b/0x5f0 acpi_bus_check_add+0xc4/0x250 ... To address this issue, make acpi_extract_power_resources() check for duplicates and simply skip them when found. Cc: All applicable Signed-off-by: Hans de Goede [ rjw: Subject & changelog, comments ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

ACPI / power: Avoid maybe-uninitialized warning

2017-04-30T03:49:13+00:00

commit fe8c470ab87d90e4b5115902dd94eced7e3305c3 upstream. gcc -O2 cannot always prove that the loop in acpi_power_get_inferred_state() is enterered at least once, so it assumes that cur_state might not get initialized: drivers/acpi/power.c: In function 'acpi_power_get_inferred_state': drivers/acpi/power.c:222:9: error: 'cur_state' may be used uninitialized in this function [-Werror=maybe-uninitialized] This sets the variable to zero at the start of the loop, to ensure that there is well-defined behavior even for an empty list. This gets rid of the warning. The warning first showed up when the -Os flag got removed in a bug fix patch in linux-4.11-rc5. I would suggest merging this addon patch on top of that bug fix to avoid introducing a new warning in the stable kernels. Fixes: 61b79e16c68d (ACPI: Fix incompatibility with mcount-based function graph tracing) Signed-off-by: Arnd Bergmann Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

ACPI: Remove duplicate definitions of PREFIX

2014-03-19T01:01:57+00:00

We already have a macro for PREFIX of "ACPI: " in drivers/acpi/internal.h, so remove the duplicate ones in ACPI drivers when internal.h is included. Signed-off-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki

ACPI: Clean up inclusions of ACPI header files

2013-12-07T00:03:14+00:00

Replace direct inclusions of , and , which are incorrect, with inclusions and remove some inclusions of those files that aren't necessary. First of all, , and should not be included directly from any files that are built for CONFIG_ACPI unset, because that generally leads to build warnings about undefined symbols in !CONFIG_ACPI builds. For CONFIG_ACPI set, includes those files and for CONFIG_ACPI unset it provides stub ACPI symbols to be used in that case. Second, there are ordering dependencies between those files that always have to be met. Namely, it is required that be included prior to so that the acpi_pci_root declarations the latter depends on are always there. And which provides basic ACPICA type declarations should always be included prior to any other ACPI headers in CONFIG_ACPI builds. That also is taken care of including as appropriate. Signed-off-by: Lv Zheng Cc: Greg Kroah-Hartman Cc: Matthew Garrett Cc: Tony Luck Cc: "H. Peter Anvin" Acked-by: Bjorn Helgaas (drivers/pci stuff) Acked-by: Konrad Rzeszutek Wilk (Xen stuff) Signed-off-by: Rafael J. Wysocki

ACPI / power: Drop automaitc resume of power resource dependent devices

2013-10-16T21:05:42+00:00

The mechanism causing devices depending on a given power resource (that is, devices that can be in D0 only if that power resource is on) to be resumed automatically when the power resource is turned on (and their "inferred" power state becomes D0 as a result) is inherently racy and in fact unnecessary. It is racy, because if the power resource is turned on and then immediately off, the device resume triggered by the first transition to "on" may still happen, causing the power resource to be turned on again. That again will trigger the "resume of dependent devices" mechanism, but if the devices in question are not in use, they will be suspended in the meantime causing the power resource to be turned off. However, the "resume of dependent devices" will next resume them again and so on. In some cases (USB port PM in particular) that leads to an endless busy loop of flipping the resource on and off continuously. It is needless, because whoever turns a power resource on will most likely turn it off at some point and the devices that go into "D0" as a result of turning it on will then go back into D3cold (generally, the state they were in before). Moreover, turning on all power resources a device needs to go into D0 is not sufficient for a full transition into D0 in general. Namely, _PS0 may need to be executed in addition to that in some cases. This means that the whole rationale of the "resume of dependent devices" mechanism was incorrect to begin with and it's best to remove it entirely. Signed-off-by: Rafael J. Wysocki

ACPI / power: Release resource_lock after acpi_power_get_state() return error

2013-10-15T22:26:42+00:00

In acpi_resume_power_resources() resource_lock should be released when acpi_power_get_state() fails and before passing to next power resource on the list. Signed-off-by: Lan Tianyu Signed-off-by: Rafael J. Wysocki

Merge branch 'acpi-pm'

2013-08-26T23:28:17+00:00

* acpi-pm: ACPI / PM: Add state information to error message in acpi_device_set_power() ACPI / PM: Remove redundant power manageable check from acpi_bus_set_power() ACPI / PM: Use ACPI_STATE_D3_COLD instead of ACPI_STATE_D3 everywhere ACPI / PM: Make messages in acpi_device_set_power() print device names ACPI / PM: Only set power states of devices that are power manageable

ACPI / PM: Use ACPI_STATE_D3_COLD instead of ACPI_STATE_D3 everywhere

2013-07-30T12:36:20+00:00

There are several places in the tree where ACPI_STATE_D3 is used instead of ACPI_STATE_D3_COLD which should be used instead for clarity. Modify them all to use ACPI_STATE_D3_COLD as appropriate. [The definition of ACPI_STATE_D3 itself cannot go away at this point as it is part of ACPICA.] Signed-off-by: Rafael J. Wysocki Reviewed-by: Aaron Lu

ACPI: introduce helper function acpi_execute_simple_method()

2013-07-14T23:33:10+00:00

Introduce helper function acpi_execute_simple_method() and use it in a number of places to simplify code. [rjw: Changelog] Signed-off-by: Jiang Liu Signed-off-by: Rafael J. Wysocki

ACPI / power: add missing newline to debug messages

2013-07-05T11:30:20+00:00

There are few places in power.c where debug messages have no newline at the end. Reading such debug messages from dmesg is not fun, so fix this by adding the missing newlines. Signed-off-by: Mika Westerberg Cc: All Signed-off-by: Rafael J. Wysocki