This patch adds a .notify() method. The presence of .notify() causes
Linux/ACPI to manage event handlers and notify handlers on our behalf,
so we don't have to install and remove them ourselves.
This driver relies on seeing system notify events, not device-specific
ones (because it used ACPI_SYSTEM_NOTIFY). We use the
ACPI_DRIVER_ALL_NOTIFY_EVENTS driver flag to request all events, then
just ignore any device events we get.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
CC: Corentin Chary <corentincj@iksaif.net>
CC: Karol Kozimor <sziwan@users.sourceforge.net>
CC: acpi4asus-user@lists.sourceforge.net
Signed-off-by: Len Brown <len.brown@intel.com>
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.
We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.
But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.
->read_proc/->write_proc were just fixed to not require ->owner for
protection.
rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.
Removing ->owner will also make PDE smaller.
So, let's nuke it.
Kudos to Jeff Layton for reminding about this, let's say, oversight.
http://bugzilla.kernel.org/show_bug.cgi?id=12454
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
These are platform specific drivers that happen to use ACPI,
while drivers/acpi/ is for code that implements ACPI itself.
Signed-off-by: Len Brown <len.brown@intel.com>
Bjorn Helgaas