kernel_optimize_test/drivers/pci/hotplug
Stefano Stabellini 47e9037ac1 PCI hotplug: acpiphp: set current_state to D0 in register_slot
If a device doesn't support power management (pm_cap == 0) but it is
acpi_pci_power_manageable() because there is a _PS0 method declared for
it and _EJ0 is also declared for the slot then nobody is going to set
current_state = PCI_D0 for this device.  This is what I think it is
happening:

pci_enable_device
    |
__pci_enable_device_flags
/* here we do not set current_state because !pm_cap */
    |
do_pci_enable_device
    |
pci_set_power_state
    |
__pci_start_power_transition
    |
pci_platform_power_transition
/* platform_pci_power_manageable() calls acpi_pci_power_manageable that
 * returns true */
    |
platform_pci_set_power_state
/* acpi_pci_set_power_state gets called and does nothing because the
 * acpi device has _EJ0, see the comment "If the ACPI device has _EJ0,
 * ignore the device" */

at this point if we refer to the commit message that introduced the
comment above (10b3dcae0f), it is up to
the hotplug driver to set the state to D0.
However AFAICT the pci hotplug driver never does, in fact
drivers/pci/hotplug/acpiphp_glue.c:register_slot sets the slot flags to
(SLOT_ENABLED | SLOT_POWEREDON) but it does not set the pci device
current state to PCI_D0.

So my proposed fix is also to set current_state = PCI_D0 in
register_slot.
Comments are very welcome.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-03-04 10:42:22 -08:00
..
acpi_pcihp.c PCI: PCIe: Ask BIOS for control of all native services at once 2010-08-24 13:47:33 -07:00
acpiphp_core.c
acpiphp_glue.c PCI hotplug: acpiphp: set current_state to D0 in register_slot 2011-03-04 10:42:22 -08:00
acpiphp_ibm.c sysfs: add struct file* to bin_attr callbacks 2010-05-21 09:37:31 -07:00
acpiphp.h headers: kobject.h redux 2011-01-10 08:51:44 -08:00
cpci_hotplug_core.c
cpci_hotplug_pci.c
cpci_hotplug.h
cpcihp_generic.c
cpcihp_zt5550.c
cpcihp_zt5550.h
cpqphp_core.c PCI: hotplug/cpqphp, fix NULL dereference 2010-06-11 13:10:21 -07:00
cpqphp_ctrl.c
cpqphp_nvram.c
cpqphp_nvram.h
cpqphp_pci.c
cpqphp_sysfs.c drivers: autoconvert trivial BKL users to private mutex 2010-10-05 15:01:04 +02:00
cpqphp.h
fakephp.c PCI: use for_each_pci_dev() 2010-07-30 09:47:22 -07:00
ibmphp_core.c
ibmphp_ebda.c PCI hotplug: ibmphp: Add check to prevent reading beyond mapped area 2010-11-11 09:34:31 -08:00
ibmphp_hpc.c PCI hotplug: ibmphp-hpc: semaphore cleanup 2010-10-15 13:09:48 -07:00
ibmphp_pci.c
ibmphp_res.c
ibmphp.h
Kconfig
Makefile
pci_hotplug_core.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
pciehp_acpi.c PCI hotplug: Fix unexpected driver unregister in pciehp_acpi.c 2010-12-23 12:51:49 -08:00
pciehp_core.c pciehp: update workqueue usage 2010-10-18 08:31:02 +02:00
pciehp_ctrl.c pciehp: update workqueue usage 2010-10-18 08:31:02 +02:00
pciehp_hpc.c pciehp: update workqueue usage 2010-10-18 08:31:02 +02:00
pciehp_pci.c PCI hotplug: pciehp: Fixed return value sign for pciehp_unconfigure_device 2010-07-30 09:29:15 -07:00
pciehp.h pciehp: update workqueue usage 2010-10-18 08:31:02 +02:00
pcihp_skeleton.c
pcihp_slot.c
rpadlpar_core.c powerpc/pseries: Flush lazy kernel mappings after unplug operations 2010-04-28 16:23:24 +10:00
rpadlpar_sysfs.c
rpadlpar.h
rpaphp_core.c powerpc/pseries: Flush lazy kernel mappings after unplug operations 2010-04-28 16:23:24 +10:00
rpaphp_pci.c
rpaphp_slot.c headers: kobject.h redux 2011-01-10 08:51:44 -08:00
rpaphp.h
sgi_hotplug.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
shpchp_core.c shpchp: update workqueue usage 2010-10-18 08:33:02 +02:00
shpchp_ctrl.c shpchp: update workqueue usage 2010-10-18 08:33:02 +02:00
shpchp_hpc.c shpchp: update workqueue usage 2010-10-18 08:33:02 +02:00
shpchp_pci.c PCI hotplug: shpchp: Removed check for hotplug of display devices 2010-07-30 09:29:16 -07:00
shpchp_sysfs.c
shpchp.h shpchp: update workqueue usage 2010-10-18 08:33:02 +02:00