commit d2f6650a95 upstream.
If acpi_bus_add does not return a device and it's passed
to acpi_bus_start, bad things will happen:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: [<ffffffff8128402d>] acpi_bus_start+0x14/0x24
...
[<ffffffffa008977a>] acpiphp_bus_add+0xba/0x130 [acpiphp]
[<ffffffffa008aa72>] enable_device+0x132/0x2ff [acpiphp]
[<ffffffffa0089b68>] acpiphp_enable_slot+0xb8/0x130 [acpiphp]
[<ffffffffa0089df7>] handle_hotplug_event_func+0x87/0x190 [acpiphp]
Next patch would make this NULL pointer check obsolete, but
better having one more than one missing...
Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Minor code cleanup, no functional change. Instead of remembering
what HIDs & CIDs to add later, just add them immediately.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Every acpi_device has at least one ID (if there's no _HID or _CID, we
give it a synthetic or default ID). So there's no longer a need to
check whether an ID exists; we can just use it.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We now keep a single list of IDs that includes both the _HID and any
_CIDs. We no longer need to keep track of whether the device has a _CID.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
There's no need to treat _HID and _CID differently. Keeping them in
a single list makes code that uses the IDs a little simpler because it
can just traverse the list rather than checking "do we have a HID?",
"do we have any CIDs?"
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This makes sure every acpi_device has at least one ID. If we build an
acpi_device for a namespace node with no _HID or _CID, we sometimes
synthesize an ID like "LNXCPU" or "LNXVIDEO". If we don't even have
that, give it a default "device" ID.
Note that this means things like:
/sys/devices/LNXSYSTM:00/LNXSYBUS:00/HWP0001:00/HWP0002:04/device:00
(a PCI slot SxFy device) will have "hid" and "modprobe" entries, where
they didn't before. These aren't very useful (a HID of "device" doesn't
tell you what *kind* of device it is, so it doesn't help find a driver),
but I don't think they're harmful.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Use acpi_device_hid() rather than accessing acpi_device.pnp.hardware_id
directly.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This makes \_SB_ show up as /sys/devices/LNXSYSTM:00/LNXSYBUS:00
rather than "device:00". This has been broken for a loooong time
(at least since 2.6.13) because device->parent is an acpi_device
pointer, not a handle.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
acpi_bus_scan() traverses the namespace to enumerate devices and uses
acpi_add_single_object() to create acpi_devices. When the platform
notifies us of a hot-plug event, we need to traverse part of the namespace
again to figure out what appeared or disappeared. (We don't yet call
acpi_bus_scan() during hot-plug, but I plan to do that in the future.)
This patch makes acpi_add_single_object() notice when we already have
an acpi_device, so we don't need to make a new one.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This patch adds acpi_bus_type_and_status(), which determines the type
of the object and whether we want to build an acpi_device for it. If
it is acpi_device-worthy, it returns the type and the device's current
status.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
acpi_bus_scan() currently walks the namespace manually. This patch changes
it to use acpi_walk_namespace() instead.
Besides removing some complicated code, this means we take advantage of the
namespace locking done by acpi_walk_namespace(). The locking isn't so
important at boot-time, but I hope to eventually use this same path to
handle hot-addition of devices, when it will be important.
Note that acpi_walk_namespace() does not actually visit the starting node
first, so we need to do that by hand first.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We can identify the root of the ACPI device tree by the fact that it
has no parent. This is simpler than passing around ACPI_BUS_TYPE_SYSTEM
and will help remove special treatment of the device tree root.
Currently, we add the root by hand with ACPI_BUS_TYPE_SYSTEM. If we
traverse the tree treating the root as just another device and use
acpi_get_type(), the root shows up as ACPI_TYPE_DEVICE.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This patch changes the order so we enumerate in the "root, namespace,
functional fixed" order instead of the "root, functional fixed, namespace"
order. When I change acpi_bus_scan() to use acpi_walk_namespace(), it
will use the former order, so this patch isolates the order change for
bisectability.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This patch changes acpi_bus_scan() to take an acpi_handle rather than an
acpi_device pointer. I plan to use acpi_bus_scan() in the hotplug path,
and I'd rather not assume that notifications only go to nodes that already
have acpi_devices.
This will also help remove the special case for adding the root node. We
currently add the root by hand before acpi_bus_scan(), but using a handle
here means we can start the acpi_bus_scan() directly with the root even
though it doesn't have an acpi_device yet.
Note that acpi_bus_scan() currently adds and/or starts the *children* of
its device argument. It doesn't do anything with the device itself.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This patch adds acpi_bus_get_parent(), which ascends the namespace until
it finds a parent with an acpi_device.
Then we use acpi_bus_get_parent() in acpi_add_single_object(), so callers
don't have to figure out or keep track of the parent acpi_device.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
acpi_add_single_object() is static, and all callers supply a valid "child"
argument, so we don't need to check it. This patch also remove some
unnecessary initializations.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We now save the ACPI bus "device_type" in the acpi_device structure, so
we don't need to pass it around explicitly anymore.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We only pass the "type" to acpi_device_set_context() so we know whether
the device has a handle to which we can attach the acpi_device pointer.
But it's safer to just check for the handle directly, since it's in the
acpi_device already.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Most uses of the ACPI bus device_type (ACPI_BUS_TYPE_DEVICE,
ACPI_BUS_TYPE_POWER, etc) are during device initialization, but
we do need it later for notify handler installation, since that
is different for fixed hardware devices vs. namespace devices.
This patch saves the device_type in the acpi_device structure,
so we can check that rather than comparing against the _HID string.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
In several cases, functions take handle and parent device pointers in
addition to acpi_device pointers. But the acpi_device structure contains
both the handle and the parent pointer, so it's pointless and error-prone
to pass them all. This patch removes the unnecessary "handle" and "parent"
arguments.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add debug output for adding an ACPI device. Enable this with
"acpi.debug_layer=0x00010000" (ACPI_BUS_COMPONENT).
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
