Hibernation breaks on EeePC 701 as a result of attempting to put one
of its (driverless) devices into a low power state. Avoid that by
not attepmting to power manage driverless devices during hibernation.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-and-tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
If one of device drivers refuses to suspend by returning error code
from its ->suspend() callback, the devices that have already been
suspended are resumed by executing their drivers' ->resume()
callbacks. Some of these callbacks expect the device's
configuration space to be restored if the device has been put into
D3 before they are called. Unfortunately, this mechanism has been
broken by recent changes moving the restoration of config spaces
of some devices (most importantly, USB controllers and HDA Intel)
into the resume callbacks executed with interrupts off. Obviously,
these callbacks are not invoked in the suspend error path and, as a
result, the system cannot be successfully brought back into the
working state in case of a suspend error. The same thing happens
in the hibernation error path right before putting the system into
S4.
Similarly, the suspend testing facility associated with the
/sys/power/pm_test file is broken, because it uses the very same
mechanism that is used in the suspend and hibernation error paths.
Fix the breakage by making the PCI core restore the configuration
spaces of PCI devices that haven't been restored already before
pci_pm_resume() is called for those devices by the PM core.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
There is a problem in our handling of suspend-resume of PCI devices that
many of them have their standard config registers restored with
interrupts enabled and they are put into the full power state with
interrupts enabled as well. This may lead to the following scenario:
* an interrupt vector is shared between two or more devices
* one device is resumed earlier and generates an interrupt
* the interrupt handler of another device tries to handle it and
attempts to access the device the config space of which hasn't been
restored yet and/or which still is in a low power state
* the system crashes as a result
To prevent this from happening we should restore the standard
configuration registers of all devices with interrupts disabled and we
should put them into the D0 power state right after that.
Unfortunately, this cannot be done using the existing
pci_set_power_state(), because it can sleep. Also, to do it we have to
make sure that the config spaces of all devices were actually saved
during suspend.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Put PM callbacks in drivers/pci/pci-driver.c in the order in which
they are executed which makes it much easier to follow the code.
No functional changes should result from this.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
It should be quite clear that it generally makes sense to execute
the default PM callbacks (ie. the callbacks used for handling
suspend, hibernation and resume of PCI devices without drivers) for
all devices. Of course, the drivers that provide legacy PCI PM
support (ie. the ->suspend, ->suspend_late, ->resume_early
or ->resume hooks in the pci_driver structure), carry out these
operations too, so we can't do it for devices with such drivers.
Still, we can make the default PM callbacks run for devices with
drivers using the new framework (ie. implement the pm object), since
there are no such drivers at the moment.
This also simplifies the code and makes it smaller.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The size of drivers/pci/pci-driver.c can be reduced quite a bit
if pci_fixup_device() is called from the legacy PM callbacks, so make
it happen.
No functional changes should result from this.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Rename two functions and rearrange code in drivers/pci/pci-driver.c
so that it's easier to follow. In particular, separate invocations
of the legacy callbacks from the rest of the new callbacks' code.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
It generally is better to avoid accessing devices behind bridges that
may not be in the D0 power state, because in that case the bridges'
secondary buses may not be accessible. For this reason, during the
early phase of resume (ie. with interrupts disabled), before
restoring the standard config registers of a device, check the power
state of the bridge the device is behind and postpone the restoration
of the device's config space, as well as any other operations that
would involve accessing the device, if that state is not D0.
In such cases the restoration of the device's config space will be
retried during the "normal" phase of resume (ie. with interrupts
enabled), so that the bridge can be put into D0 before that happens.
Also, save standard configuration registers of PCI devices during the
"normal" phase of suspend (ie. with interrupts enabled), so that the
bridges the devices are behind can be put into low power states (we
don't put bridges into low power states at the moment, but we may
want to do it in the future and it seems reasonable to design for
that).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Move pci_has_legacy_pm_support() closer to the functions that
call it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
PCI devices without drivers can be put into low power states during
suspend with the help of pci_prepare_to_sleep() and prevented from
generating wake-up events during resume with the help of
pci_enable_wake(). However, it's better not to put bridges into
low power states during suspend, because that might result in entire
bus segments being powered off.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
PCI devices without drivers are not disabled during suspend and
hibernation, but they are enabled during resume, with the help of
pci_reenable_device(), so there is an unbalanced execution of
pcibios_enable_device() in the resume code path.
To correct this introduce function pci_disable_enabled_device()
that will disable the argument device, if it is enabled when the
function is being run, without updating the device's pci_dev
structure and use it in the suspend code path to balance the
pci_reenable_device() executed during resume.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_fixup_device() is called too early in pci_pm_poweroff() and too
late in pci_pm_restore(). Moreover, pci_pm_restore_noirq() calls
pci_fixup_device() twice and in a wrong way. Fix that.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This uses work_on_cpu(), rather than altering the cpumask of the
thread which we happen to be.
Note the cleanups:
1) I've removed the CONFIG_NUMA test, since dev_to_node() returns -1
for !CONFIG_NUMA anyway and the compiler will eliminate it.
2) No need to reset mempolicy to default (a bad idea anyway) since
work_on_cpu is run from a workqueue.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
commit b41d6cf38e (PCI: Check dynids driver_data value for validity)
requires all drivers to include an id table to try and match
driver_data. Before validating driver_data check driver has an id
table.
Acked-by: Jean Delvare <khali@linux-fr.org>
Cc: Milton Miller <miltonm@bga.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Rework the handling of suspend and resume of PCI devices which have
no drivers or the drivers of which do not provide any suspend-resume
callbacks in such a way that their standard PCI configuration
registers will be saved and restored with interrupts disabled. This
should prevent such devices, including PCI bridges, from being
resumed too late to be able to function correctly during the resume
of the other PCI devices that may depend on them.
Also, to remove one possible source of future confusion, drop the
default handling of suspend and resume for PCI devices with drivers
providing the 'pm' object introduced by the new suspend-resume
framework (there are no such PCI drivers at the moment).
This patch addresses the regression from 2.6.26 tracked as
http://bugzilla.kernel.org/show_bug.cgi?id=12121 .
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
PM: Simplify the new suspend/hibernation framework for devices
Following the discussion at the Kernel Summit, simplify the new
device PM framework by merging 'struct pm_ops' and
'struct pm_ext_ops' and removing pointers to 'struct pm_ext_ops'
from 'struct platform_driver' and 'struct pci_driver'.
After this change, the suspend/hibernation callbacks will only
reside in 'struct device_driver' as well as at the bus type/
device class/device type level. Accordingly, PCI and platform
device drivers are now expected to put their suspend/hibernation
callbacks into the 'struct device_driver' embedded in
'struct pci_driver' or 'struct platform_driver', respectively.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Only accept dynids whose driver_data value matches one of the driver's
pci_driver_id entries. This prevents the user from accidentally passing
values the drivers do not expect.
Cc: Milton Miller <miltonm@bga.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The driver flag dynids.use_driver_data is almost consistently not set,
and causes more problems than it solves. It was initially intended as a
flag to indicate whether a driver's usage of driver_data had been
carefully inspected and was ready for values from userspace. That audit
was never done, so most drivers just get a 0 for driver_data when new
IDs are added from userspace via sysfs. So remove the flag, allowing
drivers to see the data directly (a followon patch validates the passed
driver_data value against what the drivers expect).
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (72 commits)
Revert "x86/PCI: ACPI based PCI gap calculation"
PCI: remove unnecessary volatile in PCIe hotplug struct controller
x86/PCI: ACPI based PCI gap calculation
PCI: include linux/pm_wakeup.h for device_set_wakeup_capable
PCI PM: Fix pci_prepare_to_sleep
x86/PCI: Fix PCI config space for domains > 0
Fix acpi_pm_device_sleep_wake() by providing a stub for CONFIG_PM_SLEEP=n
PCI: Simplify PCI device PM code
PCI PM: Introduce pci_prepare_to_sleep and pci_back_from_sleep
PCI ACPI: Rework PCI handling of wake-up
ACPI: Introduce new device wakeup flag 'prepared'
ACPI: Introduce acpi_device_sleep_wake function
PCI: rework pci_set_power_state function to call platform first
PCI: Introduce platform_pci_power_manageable function
ACPI: Introduce acpi_bus_power_manageable function
PCI: make pci_name use dev_name
PCI: handle pci_name() being const
PCI: add stub for pci_set_consistent_dma_mask()
PCI: remove unused arch pcibios_update_resource() functions
PCI: fix pci_setup_device()'s sprinting into a const buffer
...
Fixed up conflicts in various files (arch/x86/kernel/setup_64.c,
arch/x86/pci/irq.c, arch/x86/pci/pci.h, drivers/acpi/sleep/main.c,
drivers/pci/pci.c, drivers/pci/pci.h, include/acpi/acpi_bus.h) from x86
and ACPI updates manually.
Implement new suspend and hibernation callbacks for the PCI bus type.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Some quirks should be called with interrupt disabled, we can't directly
call them in .resume_early. Also the patch introduces
pci_fixup_resume_early and pci_fixup_suspend, which matches current
device core callbacks (.suspend/.resume_early).
TBD: Somebody knows why we need quirk resume should double check if a
quirk should be called in resume or resume_early. I changed some per my
understanding, but can't make sure I fixed all.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
to make sure get one online node.
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[PATCH 2/2] pci/irq: let pci_device_shutdown to call pci_msi_shutdown v2
this change
| commit 23a274c8a5
| Author: Prakash, Sathya <sathya.prakash@lsi.com>
| Date: Fri Mar 7 15:53:21 2008 +0530
|
| [SCSI] mpt fusion: Enable MSI by default for SAS controllers
|
| This patch modifies the driver to enable MSI by default for all SAS chips.
|
| Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
| Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
|
Causes the kexec of a RHEL 5.1 kernel to fail.
root casue: the rhel 5.1 kernel still uses INTx emulation. and
mptscsih_shutdown doesn't call pci_disable_msi to reenable INTx on kexec path
So call pci_msi_shutdown in the shutdown path to do the same thing to msix
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
* Use new set_cpus_allowed_ptr() function added by previous patch,
which instead of passing the "newly allowed cpus" cpumask_t arg
by value, pass it by pointer:
-int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
+int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)
* Modify CPU_MASK_ALL
Depends on:
[sched-devel]: sched: add new set_cpus_allowed_ptr function
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In an attempt to ensure memory allocation from the local node, the pci
driver temporarily replaces the current task's memory policy with the
system default policy. Trying to be a good citizen, the driver then call's
mpol_get() on the new policy. When it's finished probing, it undoes the
'_get by calling mpol_free() [on the system default policy] and then
restores the current task's saved mempolicy.
A couple of issues here:
1) it's never necessary to set a task's mempolicy to the
system default policy in order to get system default
allocation behavior. Simply set the current task's
mempolicy to NULL and allocations will fall back to
system default policy.
2) we should never [need to] call mpol_free() on the system
default policy. [I plan on trapping this with a VM_BUG_ON()
in a subsequent patch.]
This patch removes the calls to mpol_get() and mpol_free()
and uses NULL for the temporary task mempolicy to effect
default allocation behavior.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The PCI bus should not be trying to declare its own attribute type.
Especially as this code could never ever be called because the driver
core overwrites the driver kobject type to be its own internal type.
Delete all of this code as it was never being used and is not correct.
Also update my copyright on the file while I'm touching things there.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Don't try to call the "raw" sysfs_create_file when we already have a
helper function to do this kind of work for us.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6: (37 commits)
PCI: merge almost all of pci_32.h and pci_64.h together
PCI: X86: Introduce and enable PCI domain support
PCI: Add 'nodomains' boot option, and pci_domains_supported global
PCI: modify PCI bridge control ISA flag for clarity
PCI: use _CRS for PCI resource allocation
PCI: avoid P2P prefetch window for expansion ROMs
PCI: skip ISA ioresource alignment on some systems
PCI: remove transparent bridge sizing
pci: write file size to inode on proc bus file write
pci: use size stored in proc_dir_entry for proc bus files
pci: implement "pci=noaer"
PCI: fix IDE legacy mode resources
MSI: Use correct data offset for 32-bit MSI in read_msi_msg()
PCI: Fix incorrect argument order to list_add_tail() in PCI dynamic ID code
PCI: i386: Compaq EVO N800c needs PCI bus renumbering
PCI: Remove no longer correct documentation regarding MSI vector assignment
PCI: re-enable onboard sound on "MSI K8T Neo2-FIR"
PCI: quirk_vt82c586_acpi: Omit reading PCI revision ID
PCI: quirk amd_8131_mmrbc: Omit reading pci revision ID
cpqphp: Use PCI_CLASS_REVISION instead of PCI_REVISION_ID for read
...
The code for dynamically assigning new ids to PCI drivers,
store_new_id(), calls list_add_tail() with the list head and new node
arguments in reversed order.
The result is that every new id written essentially overwrites the
previous list of ids.
Caught with the help of Rusty's "horribly bad" list_node patch:
http://lkml.org/lkml/2007/6/10/10
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.
Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch removes the PCI_MULTITHREAD_PROBE option that had already
been marked as broken.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently, there is no minimum number of fields required when adding
a new device ID to a PCI driver through the new_id sysfs file. It is
possible to add a new ID with only the vendor ID set, causing the
driver to attempt to attach to all PCI devices from that vendor. This
has been reported to happen accidentally:
http://lists.lm-sensors.org/pipermail/lm-sensors/2007-March/019366.html
It is even possible to not even set the vendor ID field, causing the
driver to attempt to attach to _all_ the PCI devices.
This sounds dangerous and I fail to see any valid use of this
"feature". Thus I suggest that we now require at least the first two
fields (vendor ID and device ID) to be set. For what it's worth, this
is what the USB subsystem does.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make multithreaded probing work per subsystem instead of per driver.
It doesn't make much sense to probe the same device for multiple drivers in
parallel (after all, only one driver can bind to the device). Instead, create
a probing thread for each device that probes the drivers one after another.
Also make the decision to use multi-threaded probe per bus instead of per
device and adapt the pci code.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Original patch was posted as "PCI : Move pci_fixup_device and is_enabled".
This 1 of 3 patches does:
- reverts small part of Inaky's patch
(remove __pci_enable_device)
This change will be recovered by 3rd patch.
- temporarily remove pci_fixup_device.
This change will be recovered by 2nd patch.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds the module name to all PCI drivers, if they are built into the
kernel or not. It will show up in /sys/modules/MODULE_NAME/drivers/
It also fixes up the IDE core, which was calling __pci_register_driver()
directly.
Cc: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Function short description should be on only one line.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch is designed to fix:
- Disk eating corruptor on KT7 after resume from RAM
- VIA IRQ handling
- VIA fixups for bus lockups after resume from RAM
The core of this is to add a table of resume fixups run at resume time.
We need to do this for a variety of boards and features, but particularly
we need to do this to get various critical VIA fixups done on resume.
The second part of the problem is to handle VIA IRQ number rules which
are a bit odd and need special handling for PIC interrupts. Various
patches broke various boxes and while this one may not be perfect
(hopefully it is) it ensures the workaround is applied to the right
devices only.
From: Jean Delvare <khali@linux-fr.org>
Now that PCI quirks are replayed on software resume, we can safely
re-enable the Asus SMBus unhiding quirk even when software suspend support
is enabled.
[akpm@osdl.org: fix const warning]
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Unfortunately, the .../new_id feature does not work with the 8250_pci
driver.
The reason for this comes down to the way .../new_id is implemented.
When PCI tries to match a driver to a device, it checks the modules
static device ID tables _before_ checking the dynamic new_id tables.
When a driver is capable of matching by ID, and falls back to matching
by class (as 8250_pci does), this makes it absolutely impossible to
specify a board by ID, and as such the correct driver_data value to
use with it.
Let's say you have a serial board with vendor 0x1234 and device 0x5678.
It's class is set to PCI_CLASS_COMMUNICATION_SERIAL.
On boot, this card is matched to the 8250_pci driver, which tries to
probe it because it matched using the class entry. The driver finds
that it is unable to automatically detect the correct settings to use,
so it returns -ENODEV.
You know that the information the driver needs is to match this card
using a device_data value of '7'. So you echo 1234 5678 0 0 0 0 7
into new_id.
The kernel attempts to re-bind 8250_pci to this device. However,
because it scans the PCI driver tables, it _again_ matches the class
entry which has the wrong device_data. It fails.
End of story. You can't support the card without rebuilding the
kernel (or writing a specific PCI probe module to support it.)
So, can we make new_id override the driver-internal PCI ID tables?
IOW, like this:
From: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Changes the pci_{enable,disable}_device() functions to work in a
nested basis, so that eg, three calls to enable_device() require three
calls to disable_device().
The reason for this is to simplify PCI drivers for
multi-interface/capability devices. These are devices that cram more
than one interface in a single function. A relevant example of that is
the Wireless [USB] Host Controller Interface (similar to EHCI) [see
http://www.intel.com/technology/comms/wusb/whci.htm].
In these kind of devices, multiple interfaces are accessed through a
single bar and IRQ line. For that, the drivers map only the smallest
area of the bar to access their register banks and use shared IRQ
handlers.
However, because the order at which those drivers load cannot be known
ahead of time, the sequence in which the calls to pci_enable_device()
and pci_disable_device() cannot be predicted. Thus:
1. driverA starts pci_enable_device()
2. driverB starts pci_enable_device()
3. driverA shutdown pci_disable_device()
4. driverB shutdown pci_disable_device()
between steps 3 and 4, driver B would loose access to it's device,
even if it didn't intend to.
By using this modification, the device won't be disabled until all the
callers to enable() have called disable().
This is implemented by replacing 'struct pci_dev->is_enabled' from a
bitfield to an atomic use count. Each caller to enable increments it,
each caller to disable decrements it. When the count increments from 0
to 1, __pci_enable_device() is called to actually enable the
device. When it drops to zero, pci_disable_device() actually does the
disabling.
We keep the backend __pci_enable_device() for pci_default_resume() to
use and also change the sysfs method implementation, so that userspace
enabling/disabling the device doesn't disable it one time too much.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
__pci_register_driver() error path forgot to unwind.
driver_unregister() needs to be called when pci_create_newid_file() failed.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Considering below scenario:
1.Unload a PCI device's driver, the device ->current remains in PCI_D0.
2.Do suspend/resume circle. After that, BIOS puts the device to D3.
3.Reload the device driver. The calling pci_set_power_state in the
driver can't change the state to D0, as set_power_state thinks the
device is already in D0.
A bug is reported at http://bugzilla.kernel.org/show_bug.cgi?id=6024
Pat attached a patch at
http://marc.theaimsgroup.com/?l=linux-pci&m=114049761428561&w=2 for this
issue, but it's lost. As pci_set_power_state can handle D3 -> D0
correctly (restore config space), I simplified Patrick's patch.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There are numerous drivers that can use multithreaded probing but having
some kind of global flag as the way to control this makes migration to
threaded probing hard and since it enables it everywhere and is almost
as likely to cause serious pain as holding a clog dance in a minefield.
If we have a pci_driver multithread_probe flag to inherit you can turn
it on for one driver at a time.
From playing so far however I think we need a different model at the
device layer which serializes until the called probe function says "ok
you can start another one now". That would need some kind of flag and
semaphore plus a helper function.
Anyway in the absence of that this is a starting point to usefully play
with this stuff
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This provides a build and run-time option to turn on multhreaded probe
for all PCI drivers. It can cause bad problems on multi-processor
machines that take a while to find their root disks, and play havoc on
machines that don't use persistant device names for block or network
devices.
But it can cause speedups on some machines, my tiny laptop's boot goes
up by 0.4 seconds, and my desktop boots up several seconds faster.
Use at your own risk!!!
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Rafael J. Wysocki