linux-toradex.git/drivers/pci/hotplug/acpiphp_glue.c, branch v2.6.32.45

PCI hotplug: acpiphp: set current_state to D0 in register_slot

2011-03-27T18:30:28+00:00

commit 47e9037ac16637cd7f12b8790ea7ce6680e42168 upstream.

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 (10b3dcae0f275e2546e55303d64ddbb58cec7599), 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 
Signed-off-by: Jesse Barnes 
Signed-off-by: Greg Kroah-Hartman

PCI hotplug: acpiphp: use generic pci_configure_slot()

2009-09-15T00:39:12+00:00

Use the generic pci_configure_slot() rather than the acpiphp-specific
decode_hpp() and program_hpp().

Unlike the previous acpiphp-specific code, pci_configure_slot() programs
PCIe settings when an _HPX method provides them, so acpiphp-managed PCIe
devices can now be configured.

Signed-off-by: Bjorn Helgaas 
Reviewed-by: Kenji Kaneshige 
Acked-by: Kenji Kaneshige 
Signed-off-by: Jesse Barnes

PCI hotplug: clean up acpi_get_hp_params_from_firmware() interface

2009-09-15T00:38:26+00:00

This patch makes acpi_get_hp_params_from_firmware() take a
pci_dev rather than a pci_bus and makes it return a standard
int errno rather than acpi_status.

Signed-off-by: Bjorn Helgaas 
Reviewed-by: Kenji Kaneshige 
Acked-by: Kenji Kaneshige 
Signed-off-by: Jesse Barnes

PCI hotplug: acpiphp: don't cache hotplug_params in acpiphp_bridge

2009-09-15T00:38:22+00:00

We always look up hotplug_params with decode_hpp() immediately before using
them, so we don't need to save them in the acpiphp_bridge struct.  This
patch follows the example of program_fw_provided_values() in pciehp_pci.c
and shpchp_pci.c by just keeping the params on the stack while we need them.

Signed-off-by: Bjorn Helgaas 
Reviewed-by: Alex Chiang 
Reviewed-by: Kenji Kaneshige 
Acked-by: Kenji Kaneshige 
Signed-off-by: Jesse Barnes

PCI hotplug: acpiphp: remove superfluous _HPP/_HPX evaluation

2009-09-15T00:38:19+00:00

decode_hpp() looks up hotplug PCI parameters from ACPI and saves them
in the acpiphp_bridge structure.  These parameters (in bridge->hpp) are
only used by the acpiphp_set_hpp_values() -> program_hpp() path.  In
that path, we always call decode_hpp() before program_hpp(), so there's
no need to do it in init_bridge_misc().

Signed-off-by: Bjorn Helgaas 
Reviewed-by: Alex Chiang 
Reviewed-by: Kenji Kaneshige 
Acked-by: Kenji Kaneshige 
Signed-off-by: Jesse Barnes

PCI Hotplug: convert acpi_pci_detect_ejectable() to take an acpi_handle

2009-09-14T15:46:58+00:00

acpi_pci_detect_ejectable() goes through effort to convert its
struct pci_bus arg to an acpi_handle, but every time we use this
interface, we already have the handle available.

So let's just use the handle instead of converting back and forth.

Reviewed-by: Kenji Kaneshige 
Tested-by: Kenji Kaneshige 
Signed-off-by: Alex Chiang 
Signed-off-by: Jesse Barnes

PCI Hotplug: acpiphp: find bridges the easy way

2009-09-14T15:46:48+00:00

Instead of constantly evaluating _ADR and _SEG over and over again,
let's simplify our lives by using:

	acpi_pci_find_root() for root bridges
	acpi_get_pci_dev() for p2p bridges

This change eliminates some copy 'n paste code and also allows us
to simplify some internal interfaces.

Reviewed-by: Kenji Kaneshige 
Tested-by: Kenji Kaneshige 
Cc: Bjorn Helgaas 
Signed-off-by: Alex Chiang 
Signed-off-by: Jesse Barnes

PCI Hotplug: acpiphp: get pci_bus from acpi handle correctly

2009-09-09T20:29:23+00:00

We cannot simply call acpi_get_pci_dev() on any random ACPI handle
and hope that it works, because a PCI root bridge may not have
an associated struct pci_dev.

This is allowed per the PCI specification, and is referred to as a
non-materialized bridge.

So, depending on the type of PCI bridge that the handle points to,
use the appropriate interface to return the struct pci_bus correctly.

Reviewed-by: Bjorn Helgaas 
Signed-off-by: Alex Chiang 
Signed-off-by: Jesse Barnes

PCI Hotplug: acpiphp: convert to acpi_get_pci_dev

2009-06-18T03:32:00+00:00

Now that acpi_get_pci_dev is available, let's use it instead of
acpi_get_pci_id.

Signed-off-by: Alex Chiang 
Acked-by: Bjorn Helgaas 
Acked-by: Jesse Barnes 
Signed-off-by: Len Brown

ACPI: Introduce acpi_is_root_bridge()

2009-06-18T03:22:15+00:00

Returns whether an ACPI CA node is a PCI root bridge or not.

This API is generically useful, and shouldn't just be a hotplug function.

The implementation becomes much simpler as well.

Signed-off-by: Alex Chiang 
Acked-by: Bjorn Helgaas 
Signed-off-by: Len Brown