Currently, notify callbacks for fixed button events are run from
interrupt context. That is not necessary and after commit 0bf6368ee8
(ACPI / button: Add ACPI Button event via netlink routine) it causes
netlink routines to be called from interrupt context which is not
correct.
Also, that is different from non-fixed device events (including
non-fixed button events) whose notify callbacks are all executed from
process context.
For the above reasons, make fixed button device notify callbacks run
in process context which will avoid the deadlock when using netlink
to report button events to user space.
Fixes: 0bf6368ee8 (ACPI / button: Add ACPI Button event via netlink routine)
Link: https://lkml.org/lkml/2014/8/21/606
Reported-by: Benjamin Block <bebl@mageta.org>
Reported-by: Knut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
[rjw: Function names, subject and changelog.]
Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We generally don't allow ACPI drivers to bind to ACPI device objects
that companion "physical" device objects are created for to avoid
situations in which two different drivers may attempt to handle one
device at the same time. Recent ACPI device enumeration rework
extended that approach to ACPI PNP devices by starting to use a scan
handler for enumerating them. However, we previously allowed ACPI
drivers to bind to ACPI device objects with existing PNP device
companions and changing that led to functional regressions on some
systems.
For this reason, add a special check for PNP devices in
acpi_device_probe() so that ACPI drivers can bind to ACPI device
objects having existing PNP device companions as before.
Fixes: eec15edbb0 (ACPI / PNP: use device ID list for PNPACPI device enumeration)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=81511
Link: https://bugzilla.kernel.org/show_bug.cgi?id=81971
Reported-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Reported-by: Dirk Griesbach <spamthis@freenet.de>
Cc: 3.16+ <stable@vger.kernel.org> # 3.16+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI device enumeration code in Linux assumes that buttons always
are wakeup devices, so it calls acpi_setup_gpe_for_wake() for them
which leads to undesirable side effects. Namely, that function sets
up implicit device wake notification mechanism for a given GPE if
there is no handler method in the ACPI namespace, which from the
ACPICA's perspective means that there always is a way to handle
that GPE if enabled. However, we don't handle wake notify events
for buttons, so if there are no handler methods for their GPEs in
the namespace, enabling a button GPE at run time leads to a GPE
storm in some cases (the GPE triggers, ACPICA carries out the
implicit wake notification for it which isn't handled, so the
GPE triggers again and so on).
To prevent that from happening use acpi_mark_gpe_for_wake()
instead of acpi_setup_gpe_for_wake() for buttons which will cause
ACPICA to only enable button GPEs if there are handler methods for
the in the namespace.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since all of the acpi_set_hp_context() callers pass at least one NULL
function pointer and one caller passes NULL function pointers only
to it, drop function pointer arguments from acpi_set_hp_context()
and make the callers initialize the function pointers in struct
acpi_hotplug_context by themselves before passing it to
acpi_set_hp_context().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
* acpi-enumeration:
ACPI / scan: use platform bus type by default for _HID enumeration
ACPI / scan: always register ACPI LPSS scan handler
ACPI / scan: always register memory hotplug scan handler
ACPI / scan: always register container scan handler
ACPI / scan: Change the meaning of missing .attach() in scan handlers
ACPI / scan: introduce platform_id device PNP type flag
ACPI / scan: drop unsupported serial IDs from PNP ACPI scan handler ID list
ACPI / scan: drop IDs that do not comply with the ACPI PNP ID rule
ACPI / PNP: use device ID list for PNPACPI device enumeration
ACPI / scan: .match() callback for ACPI scan handlers
* acpi-pm:
ACPI / PM: Export rest of the subsys PM callbacks
ACPI / PM: Avoid resuming devices in ACPI PM domain during system suspend
ACPI / PM: Hold ACPI scan lock over the "freeze" sleep state
ACPI / PM: Export acpi_target_system_state() to modules
Because of the growing demand for enumerating ACPI devices to
platform bus, change the code to enumerate ACPI device objects to
platform bus by default. Namely, create platform devices for the
ACPI device objects that
1. Have pnp.type.platform_id set (device objects with _HID currently).
2. Do not have a scan handler attached.
3. Are not SPI/I2C slave devices (that should be enumerated to the
appropriate buses bus by their parent).
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Subject and changelog, rebase and code cleanup]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Currently, some scan handlers can be compiled out entirely, which
leaves the device objects they normally attach to without a scan
handler. This isn't a problem as long as we don't have any default
enumeration mechanism that applies to all devices without a scan
handler. However, if such a default enumeration is added, it still
should not be applied to devices that are normally attached to by
scan handlers, because that may result in creating "physical" device
objects of a wrong type for them.
Since we are going to create platform device objects for all ACPI
device objects with pnp.type.platform_id set by default, clear
pnp.type.platform_id where there is a matching scan handler without
an .attach() callback and otherwise simply treat that scan handler
as though the .attach() callback was present but always returned 0.
This will allow us to compile out scan handler callbacks and leave
the device ID lists used by them so as to prevent creating platform
device objects for the matching ACPI devices.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Only certain types of ACPI device objects can be enumerated as
platform devices, so in order to distinguish them from the others
introduce a new ACPI device PNP type flag, platform_id, and set it
for devices with a valid _HID to start with.
This change is based on a Zhang Rui's prototype.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
ACPI can be used to enumerate PNP devices, but the code does not
handle this in the right way currently. Namely, if an ACPI device
object
1. Has a _CRS method,
2. Has an identification of
"three capital characters followed by four hex digits",
3. Is not in the excluded IDs list,
it will be enumerated to PNP bus (that is, a PNP device object will
be create for it). This means that, actually, the PNP bus type is
used as the default bus type for enumerating _HID devices in ACPI.
However, more and more _HID devices need to be enumerated to the
platform bus instead (that is, platform device objects need to be
created for them). As a result, the device ID list in acpi_platform.c
is used to enforce creating platform device objects rather than PNP
device objects for matching devices. That list has been continuously
growing recently, unfortunately, and it is pretty much guaranteed to
grow even more in the future.
To address that problem it is better to enumerate _HID devices
as platform devices by default. To this end, change the way of
enumerating PNP devices by adding a PNP ACPI scan handler that
will use a device ID list to create PNP devices for the ACPI
device objects whose device IDs are present in that list.
The initial device ID list in the PNP ACPI scan handler contains
all of the pnp_device_id strings from all the existing PNP drivers,
so this change should be transparent to the PNP core and all of the
PNP drivers. Still, in the future it should be possible to reduce
its size by converting PNP drivers that need not be PNP for any
technical reasons into platform drivers.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Rewrote the changelog, modified the PNP ACPI scan handler code]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Introduce a .match() callback for ACPI scan handlers to allow them to
use more elaborate matching algorithms if necessary. That is needed
for the upcoming PNP scan handler in particular.
This change is based on a Zhang Rui's prototype.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Rework the ACPI PM domain's PM callbacks to avoid resuming devices
during system suspend (in order to modify their wakeup settings etc.)
if that isn't necessary.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fixed hardware does not exist on HW-reduced ACPI platforms since the
programming interface for them is not implemented on them, so no need
to scan that hardware on them.
This patch avoids creating the fixed power button ACPI device and
eliminates a probe error message from ACPI button driver on ASUS T100.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* acpi-ost:
ACPI: Drop acpi_evaluate_hotplug_ost() and ACPI_HOTPLUG_OST
ACPI: use device name LNXSYBUS.xx for ACPI \_SB and \_TZ objects
ACPI / processor: use acpi_evaluate_ost() to replace open-coded version
ACPI / PAD / xen: use acpi_evaluate_ost() to replace open-coded version
ACPI / PAD: use acpi_evaluate_ost() to replace open-coded version
ACPI: rename acpi_evaluate_hotplug_ost() to acpi_evaluate_ost()
Since the only function executed by acpi_hotplug_execute() is
acpi_device_hotplug() and it only is called by the ACPI core,
simplify its definition so that it only takes two arguments, the
ACPI device object pointer and event code, rename it to
acpi_hotplug_schedule() and move its header from acpi_bus.h to
the ACPI core's internal header file internal.h. Modify the
definition of acpi_device_hotplug() so that its first argument is
an ACPI device object pointer and modify the definition of
struct acpi_hp_work accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Replace acpi_evaluate_hotplug_ost() with acpi_evaluate_ost()
everywhere and drop the ACPI_HOTPLUG_OST symbol so that hotplug
_OST is supported unconditionally.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Modify the SATA subsystem to add hotplug contexts to ACPI companions
of SATA devices and ports instead of registering special ACPI dock
operations using register_hotplug_dock_device().
That change will allow the entire code handling those special ACPI
dock operations to be dropped in the next commit.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
In order to avoid the need to register special ACPI dock
operations for SATA devices add a .uevent() callback pointer to
struct acpi_hotplug_context and make dock_hotplug_event() use that
callback if available. Also rename the existing .event() callback
in struct acpi_hotplug_context to .notify() to avoid possible
confusion in the future.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use device name "LNXSYBUS:xx" instead of "device.xx" for ACPI objects
\_SB and \_TZ.
BTW, the original check of "handle == ACPI_ROOT_OBJECT" in statment
"else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT)"
is always false because of the code at the begin of that block.
if (handle == ACPI_ROOT_OBJECT) {
acpi_add_id(pnp, ACPI_SYSTEM_HID);
break;
}
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since we already know what the device's PNP IDs are when
acpi_device_is_battery() is called, it is not necessary to run
acpi_get_object_info() for the device in that function. Instead, if
acpi_device_is_battery() is passed a pointer to a struct acpi_device
object, it can use the list of PNP IDs from that object, so make that
happen and modify the function's header accordingly
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI dock station code carries out an extra namespace scan
before the main one in order to find and register all of the dock
device objects. Then, it registers a notify handler for each of
them for handling dock events.
However, dock device objects need not be scanned for upfront. They
very well can be enumerated and registered during the first phase
of the main namespace scan, before attaching scan handlers and ACPI
drivers to ACPI device objects. Then, the dependent devices can be
added to the in the second phase. That makes it possible to drop
the extra namespace scan, so do it.
Moreover, it is not necessary to register notify handlers for all
of the dock stations' namespace nodes, becuase notifications may
be dispatched from the global notify handler for them. Do that and
drop two functions used for dock notify handling, acpi_dock_deferred_cb()
and dock_notify_handler(), that aren't necessary any more.
Finally, some dock station objects have _HID objects matching the
ACPI container scan handler which causes it to claim those objects
and try to handle their hotplug, but that is not a good idea,
because those objects have their own special hotplug handling anyway.
For this reason, the hotplug_notify flag should not be set for ACPI
device objects representing dock stations and the container scan
handler should be made ignore those objects, so make that happen.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In some cases it may be necessary to perform certain setup/cleanup
operations on a device object representing a physical device after
it has been associated with an ACPI companion by acpi_bind_one() or
before disassociating it from that companion by acpi_unbind_one(),
respectively. If there is a struct acpi_bus_type object for the
given device's bus type, the .setup()/.cleanup() callbacks from there
are executed for these purposes. However, an analogous mechanism will
be necessary for devices whose bus types don't have corresponding
struct acpi_bus_type objects and that have specific ACPI scan handlers.
For those devices, add new .bind() and .unbind() callbacks to struct
acpi_scan_handler that will be executed by acpi_platform_notify()
right after the given device has been associated with an ACPI
comapnion and by acpi_platform_notify_remove() right before calling
acpi_unbind_one() for that device, respectively.
To make that work for scan handlers registering new devices in their
.attach() callbacks, modify acpi_scan_attach_handler() to set the
ACPI device object's handler field before calling .attach() from the
scan handler at hand.
This changeset includes a fix from Mika Westerberg.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since acpi_bus_notify() is executed on all notifications for all
devices anyway, make it execute acpi_device_hotplug() for all
hotplug events instead of installing notify handlers pointing to
the same function for all hotplug devices.
This change reduces both the size and complexity of ACPI-based device
hotplug code. Moreover, since acpi_device_hotplug() only does
significant things for devices that have either an ACPI scan handler,
or a hotplug context with .eject() defined, and those devices
had notify handlers pointing to acpi_hotplug_notify_cb() installed
before anyway, this modification shouldn't change functionality.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since acpi_hotplug_notify_cb() does not use its data argument any
more, the second argument of acpi_install_hotplug_notify_handler()
can be dropped, so do that and update its callers accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
To avoid the need to install a hotplug notify handler for each ACPI
namespace node representing a device and having a matching scan
handler, move the check whether or not the ejection of the given
device is enabled through its scan handler from acpi_hotplug_notify_cb()
to acpi_generic_hotplug_event(). Also, move the execution of
ACPI_OST_SC_EJECT_IN_PROGRESS _OST to acpi_generic_hotplug_event(),
because in acpi_hotplug_notify_cb() or in acpi_eject_store() we really
don't know whether or not the eject is going to be in progress (for
example, acpi_hotplug_execute() may still fail without queuing up the
work item).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its
hotplug context objects directly to ACPI namespace nodes representing
hotplug devices. However, after recent changes causing struct
acpi_device to be created for every namespace node representing a
device (regardless of its status), that is not necessary any more.
Moreover, it's vulnerable to the theoretical issue that the ACPI
handle passed in the context between handle_hotplug_event() and
hotplug_event_work() may become invalid in the meantime (as a
result of a concurrent table unload).
In principle, this issue might be addressed by adding a non-empty
release handler for ACPIPHP hotplug context objects analogous to
acpi_scan_drop_device(), but that would duplicate the code in that
function and in acpi_device_del_work_fn(). For this reason, it's
better to modify ACPIPHP to attach its device hotplug contexts to
struct device objects representing hotplug devices and make it
use acpi_hotplug_notify_cb() as its notify handler. At the same
time, acpi_device_hotplug() can be modified to dispatch the new
.hp.event() callback pointing to acpiphp_hotplug_event() from ACPI
device objects associated with PCI devices or use the generic
ACPI device hotplug code for device objects with matching scan
handlers.
This allows the existing code duplication between ACPIPHP and the
ACPI core to be reduced too and makes further ACPI-based device
hotplug consolidation possible.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Subsequent changes will require the ACPI core to acquire the lock
protecting the ACPIPHP hotplug contexts, so move the definition of
the lock to the core and change its name to be more generic.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
There is a slight possibility for the ACPI device object pointed to
by adev in acpi_hotplug_notify_cb() to become invalid between the
acpi_bus_get_device() that it comes from and the subsequent dereference
of that pointer under get_device(). Namely, if acpi_scan_drop_device()
runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn()
queued up by it may delete the device object in question right after
a successful execution of acpi_bus_get_device() in acpi_bus_notify().
An analogous problem is present in acpi_bus_notify() where the device
pointer coming from acpi_bus_get_device() may become invalid before
it subsequent dereference in the "if" block.
To prevent that from happening, introduce a new function,
acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device()
except that it will grab a reference to the ACPI device object returned
by it and it will do that under the ACPICA's namespace mutex. Then,
make both acpi_hotplug_notify_cb() and acpi_bus_notify() use
acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to
ensure that the pointers used by them will not become stale at one
point.
In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper
around put_device() to be used along with acpi_bus_get_acpi_device()
and make the (new) users of the latter use acpi_bus_put_acpi_device()
too.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
When an eject request is sent to an ejected ACPI device, the following
panic occurs:
ACPI: \_SB_.SCK3.CPU3: ACPI_NOTIFY_EJECT_REQUEST event
BUG: unable to handle kernel NULL pointer dereference at 0000000000000070
IP: [<ffffffff813a7cfe>] acpi_device_hotplug+0x10b/0x33b
:
Call Trace:
[<ffffffff813a24da>] acpi_hotplug_work_fn+0x1c/0x27
[<ffffffff8109cbe5>] process_one_work+0x175/0x430
[<ffffffff8109d7db>] worker_thread+0x11b/0x3a0
This is becase device->handler is NULL in acpi_device_hotplug().
This case was used to fail in acpi_hotplug_notify_cb() as the target
had no acpi_deivce. However, acpi_device now exists after ejection.
Added a check to verify if acpi_device->handler is valid for an
eject request in acpi_hotplug_notify_cb(). Note that handler passed
from an argument is still valid while acpi_device->handler is NULL.
Fixes: 202317a573 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace)
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* acpi-processor:
ACPI / scan: reduce log level of "ACPI: \_PR_.CPU4: failed to get CPU APIC ID"
ACPI / processor: Return specific error value when mapping lapic id
* acpi-hotplug:
ACPI / scan: Clear match_driver flag in acpi_bus_trim()
* acpi-init:
ACPI / init: Flag use of ACPI and ACPI idioms for power supplies to regulator API
* acpi-pm:
ACPI / PM: Use ACPI_COMPANION() to get ACPI companions of devices
* acpica:
ACPICA: Remove bool usage from ACPICA.
Drivers should not bind to struct acpi_device objects that
acpi_bus_trim() has been called for, so make that function
clear flags.match_driver for those objects.
If that is not done, an ACPI driver may theoretically try to operate
a device that is not physically present.
Fixes: 202317a573 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
* acpi-modules:
platform: introduce OF style 'modalias' support for platform bus
ACPI: fix module autoloading for ACPI enumerated devices
ACPI: add module autoloading support for ACPI enumerated devices
ACPI: fix create_modalias() return value handling
An ACPI enumerated device may have its compatible id strings.
To support the compatible ACPI ids (acpi_device->pnp.ids),
we introduced acpi_driver_match_device() to match
the driver->acpi_match_table and acpi_device->pnp.ids.
For those drivers, MODULE_DEVICE_TABLE(acpi, xxx) is used to
exports the driver module alias in the format of
"acpi:device_compatible_ids".
But in the mean time, the current code does not export the
ACPI compatible strings as part of the module_alias for the
ACPI enumerated devices, which will break the module autoloading.
Take the following piece of code for example,
static const struct acpi_device_id xxx_acpi_match[] = {
{ "INTABCD", 0 },
{ }
};
MODULE_DEVICE_TABLE(acpi, xxx_acpi_match);
If this piece of code is used in a platform driver for
an ACPI enumerated platform device, the platform driver module_alias
is "acpi:INTABCD", but the uevent attribute of its platform device node
is "platform:INTABCD:00" (PREFIX:platform_device->name).
If this piece of code is used in an i2c driver for an ACPI enumerated
i2c device, the i2c driver module_alias is "acpi:INTABCD", but
the uevent of its i2c device node is "i2c:INTABCD:00" (PREFIX:i2c_client->name).
If this piece of code is used in an spi driver for an ACPI enumerated
spi device, the spi driver module_alias is "acpi:INTABCD", but
the uevent of its spi device node is "spi:INTABCD" (PREFIX:spi_device->modalias).
The reason why the module autoloading is not broken for now is that
the uevent file of the ACPI device node is "acpi:INTABCD".
Thus it is the ACPI device node creation that loads the platform/i2c/spi driver.
So this is a problem that will affect us the day when the ACPI bus
is removed from device model.
This patch introduces two new APIs,
one for exporting ACPI ids in uevent MODALIAS field,
and another for exporting ACPI ids in device' modalias sysfs attribute.
For any bus that supports ACPI enumerated devices, it needs to invoke
these two functions for their uevent and modalias attribute.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently, create_modalias() handles the output truncated case in
an improper way (return -EINVAL).
Plus, acpi_device_uevent() and acpi_device_modalias_show() do
improper check for the create_modalias() return value as well.
This patch fixes create_modalias() to
return -EINVAL if there is an output error,
return -ENOMEM if the output is truncated,
and also fixes both acpi_device_uevent() and acpi_device_modalias_show()
to do proper return value check.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch adds a "status" attribute for an ACPI device. This status
attribute shows the value of the _STA object. The _STA object returns
current status of an ACPI device: enabled, disabled, functioning,
present.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI container devices require special hotplug handling, at least
on some systems, since generally user space needs to carry out
system-specific cleanup before it makes sense to offline devices in
the container. However, the current ACPI hotplug code for containers
first attempts to offline devices in the container and only then it
notifies user space of the container offline.
Moreover, after commit 202317a573 (ACPI / scan: Add acpi_device
objects for all device nodes in the namespace), ACPI device objects
representing containers are present as long as the ACPI namespace
nodes corresponding to them are present, which may be forever, even
if the container devices are physically detached from the system (the
return values of the corresponding _STA methods change in those
cases, but generally the namespace nodes themselves are still there).
Thus it is useful to introduce entities representing containers that
will go away during container hot-unplug.
The goal of this change is to address both the above issues.
The idea is to create a "companion" container system device for each
of the ACPI container device objects during the initial namespace
scan or on a hotplug event making the container present. That system
device will be unregistered on container removal. A new bus type
for container devices is added for this purpose, because device
offline and online operations need to be defined for them. The
online operation is a trivial function that is always successful
and the offline uses a callback pointed to by the container device's
offline member.
For ACPI containers that callback simply walks the list of ACPI
device objects right below the container object (its children) and
checks if all of their physical companion devices are offline. If
that's not the case, it returns -EBUSY and the container system
devivce cannot be put offline. Consequently, to put the container
system device offline, it is necessary to put all of the physical
devices depending on its ACPI companion object offline beforehand.
Container system devices created for ACPI container objects are
initially online. They are created by the container ACPI scan
handler whose hotplug.demand_offline flag is set. That causes
acpi_scan_hot_remove() to check if the companion container system
device is offline before attempting to remove an ACPI container or
any devices below it. If the check fails, a KOBJ_CHANGE uevent is
emitted for the container system device in question and user space
is expected to offline all devices below the container and the
container itself in response to it. Then, user space can finalize
the removal of the container with the help of its ACPI device
object's eject attribute in sysfs.
Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a new ACPI hotplug profile flag, demand_offline, such that if
set for the given ACPI device object's scan handler, it will cause
acpi_scan_hot_remove() to check if that device object's physical
companions are offline upfront and fail the hot removal if that
is not the case.
That flag will be useful to overcome a problem with containers on
some system where they can only be hot-removed after some cleanup
operations carried out by user space, which needs to be notified
of the container hot-removal before the kernel attempts to offline
devices in the container. In those cases the current implementation
of acpi_scan_hot_remove() is not sufficient, because it first tries
to offline the devices in the container and only if that is
suffcessful it tries to offline the container itself. As a result,
the container hot-removal notification is not delivered to user space
at the right time.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and
<acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h>
inclusions and remove some inclusions of those files that aren't
necessary.
First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>
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,
<linux/acpi.h> 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 <acpi/acpi_bus.h> be included
prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the
latter depends on are always there. And <acpi/acpi.h> 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
<linux/acpi.h> as appropriate.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff)
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rework acpi_bus_trim() and acpi_bus_device_attach(), which is
renamed as acpi_bus_attach(), to walk the list of each device
object's children directly and call themselves recursively for
each child instead of using acpi_walk_namespace(). This
simplifies the code quite a bit and avoids the overhead of
callbacks and the ACPICA's internal processing which are not
really necessary for these two routines.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce a static inline function for setting the status field
of struct acpi_device on the basis of a supplied u32 number,
acpi_set_device_status(), and use it instead of the horrible
horrible STRUCT_TO_INT() macro wherever applicable. Having done
that, drop STRUCT_TO_INT() (and pretend that it has never existed).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The generic ACPI hotplug code used for several types of device
doesn't handle surprise removals, mostly because those devices
currently cannot be removed by surprise in the majority of systems.
However, surprise removals should be handled by that code as well
as surprise additions of devices, so make it do that.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Move container-specific uevents from the core hotplug code to the
container scan handler's .attach() and .detach() callbacks.
This way the core will not have to special-case containers and
the uevents will be guaranteed to happen every time a container
is either scanned or trimmed as appropriate.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Rework the common ACPI device hotplug code so that it is suitable
for PCI host bridge hotplug and switch the PCI host bridge scan
handler to using the common hotplug code.
This allows quite a few lines of code that are not necessary any more
to be dropped from the PCI host bridge scan handler and removes
arbitrary differences in behavior between PCI host bridge hotplug
and ACPI-based hotplug of other components, like CPUs and memory.
Also acpi_device_hotplug() can be static now.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
