* [PATCH] PCI / PM: Restore the original behavior of pci_set_power_state()
@ 2012-06-28 10:01 Rafael J. Wysocki
2012-07-05 21:29 ` Bjorn Helgaas
0 siblings, 1 reply; 4+ messages in thread
From: Rafael J. Wysocki @ 2012-06-28 10:01 UTC (permalink / raw)
To: Bjorn Helgaas
Cc: Jesse Barnes, Linux PM mailing list, LKML, Matthew Garrett, linux-pci
From: Rafael J. Wysocki <rjw@sisk.pl>
Commit cc2893b6 (PCI: Ensure we re-enable devices on resume)
addressed the problem with USB not being powered after resume on
recent Lenovo machines, but it did that in a suboptimal way.
Namely, it should have changed the relevant code paths only,
which are pci_pm_resume_noirq() and pci_pm_restore_noirq() supposed
to restore the device's power and standard configuration registers
after system resume from suspend or hibernation. Instead, however,
it modified pci_set_power_state() which is executed in several
other situations too. That resulted in some undesirable effects,
like attempting to change a device's power state in the same way
multiple times in a row (up to as many as 4 times in a row in the
snd_hda_intel driver).
Fix the bug addressed by commit cc2893b6 in an alternative way,
by forcibly powering up all devices in pci_pm_default_resume_early(),
which is called by pci_pm_resume_noirq() and pci_pm_restore_noirq()
to restore the device's power and standard configuration registers,
and modifying pci_pm_runtime_resume() to avoid the forcible power-up
if not necessary. Then, revert the changes made by commit cc2893b6
to make the confusion introduced by it go away.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
drivers/pci/pci-driver.c | 14 ++++++++------
drivers/pci/pci.c | 19 ++++++++++++++++++-
drivers/pci/pci.h | 1 +
3 files changed, 27 insertions(+), 7 deletions(-)
Index: linux/drivers/pci/pci.c
===================================================================
--- linux.orig/drivers/pci/pci.c
+++ linux/drivers/pci/pci.c
@@ -662,6 +662,19 @@ void pci_update_current_state(struct pci
}
/**
+ * pci_power_up - Put the given device into D0 forcibly
+ * @dev: PCI device to power up
+ */
+void pci_power_up(struct pci_dev *dev)
+{
+ if (platform_pci_power_manageable(dev))
+ platform_pci_set_power_state(dev, PCI_D0);
+
+ pci_raw_set_power_state(dev, PCI_D0);
+ pci_update_current_state(dev, PCI_D0);
+}
+
+/**
* pci_platform_power_transition - Use platform to change device power state
* @dev: PCI device to handle.
* @state: State to put the device into.
@@ -707,7 +720,7 @@ static void __pci_start_power_transition
*/
int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
{
- return state >= PCI_D0 ?
+ return state > PCI_D0 ?
pci_platform_power_transition(dev, state) : -EINVAL;
}
EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
@@ -744,6 +757,10 @@ int pci_set_power_state(struct pci_dev *
*/
return 0;
+ /* Check if we're already there */
+ if (dev->current_state == state)
+ return 0;
+
__pci_start_power_transition(dev, state);
/* This device is quirked not to be put into D3, so
Index: linux/drivers/pci/pci-driver.c
===================================================================
--- linux.orig/drivers/pci/pci-driver.c
+++ linux/drivers/pci/pci-driver.c
@@ -459,16 +459,17 @@ static int pci_restore_standard_config(s
return 0;
}
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+
static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
{
- pci_restore_standard_config(pci_dev);
+ pci_power_up(pci_dev);
+ pci_restore_state(pci_dev);
pci_fixup_device(pci_fixup_resume_early, pci_dev);
}
-#endif
-
-#ifdef CONFIG_PM_SLEEP
-
/*
* Default "suspend" method for devices that have no driver provided suspend,
* or not even a driver at all (second part).
@@ -1050,7 +1051,8 @@ static int pci_pm_runtime_resume(struct
if (!pm || !pm->runtime_resume)
return -ENOSYS;
- pci_pm_default_resume_early(pci_dev);
+ pci_restore_standard_config(pci_dev);
+ pci_fixup_device(pci_fixup_resume_early, pci_dev);
__pci_enable_wake(pci_dev, PCI_D0, true, false);
pci_fixup_device(pci_fixup_resume, pci_dev);
Index: linux/drivers/pci/pci.h
===================================================================
--- linux.orig/drivers/pci/pci.h
+++ linux/drivers/pci/pci.h
@@ -67,6 +67,7 @@ struct pci_platform_pm_ops {
extern int pci_set_platform_pm(struct pci_platform_pm_ops *ops);
extern void pci_update_current_state(struct pci_dev *dev, pci_power_t state);
+extern void pci_power_up(struct pci_dev *dev);
extern void pci_disable_enabled_device(struct pci_dev *dev);
extern int pci_finish_runtime_suspend(struct pci_dev *dev);
extern int __pci_pme_wakeup(struct pci_dev *dev, void *ign);
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] PCI / PM: Restore the original behavior of pci_set_power_state()
2012-06-28 10:01 [PATCH] PCI / PM: Restore the original behavior of pci_set_power_state() Rafael J. Wysocki
@ 2012-07-05 21:29 ` Bjorn Helgaas
2012-07-05 21:57 ` Rafael J. Wysocki
0 siblings, 1 reply; 4+ messages in thread
From: Bjorn Helgaas @ 2012-07-05 21:29 UTC (permalink / raw)
To: Rafael J. Wysocki
Cc: Jesse Barnes, Linux PM mailing list, LKML, Matthew Garrett,
linux-pci, Huang Ying
On Thu, Jun 28, 2012 at 4:01 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> From: Rafael J. Wysocki <rjw@sisk.pl>
>
> Commit cc2893b6 (PCI: Ensure we re-enable devices on resume)
> addressed the problem with USB not being powered after resume on
> recent Lenovo machines, but it did that in a suboptimal way.
> Namely, it should have changed the relevant code paths only,
> which are pci_pm_resume_noirq() and pci_pm_restore_noirq() supposed
> to restore the device's power and standard configuration registers
> after system resume from suspend or hibernation. Instead, however,
> it modified pci_set_power_state() which is executed in several
> other situations too. That resulted in some undesirable effects,
> like attempting to change a device's power state in the same way
> multiple times in a row (up to as many as 4 times in a row in the
> snd_hda_intel driver).
>
> Fix the bug addressed by commit cc2893b6 in an alternative way,
> by forcibly powering up all devices in pci_pm_default_resume_early(),
> which is called by pci_pm_resume_noirq() and pci_pm_restore_noirq()
> to restore the device's power and standard configuration registers,
> and modifying pci_pm_runtime_resume() to avoid the forcible power-up
> if not necessary. Then, revert the changes made by commit cc2893b6
> to make the confusion introduced by it go away.
>
> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> ---
> drivers/pci/pci-driver.c | 14 ++++++++------
> drivers/pci/pci.c | 19 ++++++++++++++++++-
> drivers/pci/pci.h | 1 +
> 3 files changed, 27 insertions(+), 7 deletions(-)
>
> Index: linux/drivers/pci/pci.c
> ===================================================================
> --- linux.orig/drivers/pci/pci.c
> +++ linux/drivers/pci/pci.c
> @@ -662,6 +662,19 @@ void pci_update_current_state(struct pci
> }
>
> /**
> + * pci_power_up - Put the given device into D0 forcibly
> + * @dev: PCI device to power up
> + */
> +void pci_power_up(struct pci_dev *dev)
> +{
> + if (platform_pci_power_manageable(dev))
> + platform_pci_set_power_state(dev, PCI_D0);
> +
> + pci_raw_set_power_state(dev, PCI_D0);
> + pci_update_current_state(dev, PCI_D0);
> +}
> +
> +/**
> * pci_platform_power_transition - Use platform to change device power state
> * @dev: PCI device to handle.
> * @state: State to put the device into.
> @@ -707,7 +720,7 @@ static void __pci_start_power_transition
> */
> int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
> {
> - return state >= PCI_D0 ?
> + return state > PCI_D0 ?
> pci_platform_power_transition(dev, state) : -EINVAL;
This hunk conflicted with Huang's D3_COLD patches. I fixed it up; can
you check and make sure I did it correctly?
I pushed the resolution to here:
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git on the
pci/rafael-pci_set_power_state-rebase branch.
Bjorn
> }
> EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
> @@ -744,6 +757,10 @@ int pci_set_power_state(struct pci_dev *
> */
> return 0;
>
> + /* Check if we're already there */
> + if (dev->current_state == state)
> + return 0;
> +
> __pci_start_power_transition(dev, state);
>
> /* This device is quirked not to be put into D3, so
> Index: linux/drivers/pci/pci-driver.c
> ===================================================================
> --- linux.orig/drivers/pci/pci-driver.c
> +++ linux/drivers/pci/pci-driver.c
> @@ -459,16 +459,17 @@ static int pci_restore_standard_config(s
> return 0;
> }
>
> +#endif
> +
> +#ifdef CONFIG_PM_SLEEP
> +
> static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
> {
> - pci_restore_standard_config(pci_dev);
> + pci_power_up(pci_dev);
> + pci_restore_state(pci_dev);
> pci_fixup_device(pci_fixup_resume_early, pci_dev);
> }
>
> -#endif
> -
> -#ifdef CONFIG_PM_SLEEP
> -
> /*
> * Default "suspend" method for devices that have no driver provided suspend,
> * or not even a driver at all (second part).
> @@ -1050,7 +1051,8 @@ static int pci_pm_runtime_resume(struct
> if (!pm || !pm->runtime_resume)
> return -ENOSYS;
>
> - pci_pm_default_resume_early(pci_dev);
> + pci_restore_standard_config(pci_dev);
> + pci_fixup_device(pci_fixup_resume_early, pci_dev);
> __pci_enable_wake(pci_dev, PCI_D0, true, false);
> pci_fixup_device(pci_fixup_resume, pci_dev);
>
> Index: linux/drivers/pci/pci.h
> ===================================================================
> --- linux.orig/drivers/pci/pci.h
> +++ linux/drivers/pci/pci.h
> @@ -67,6 +67,7 @@ struct pci_platform_pm_ops {
>
> extern int pci_set_platform_pm(struct pci_platform_pm_ops *ops);
> extern void pci_update_current_state(struct pci_dev *dev, pci_power_t state);
> +extern void pci_power_up(struct pci_dev *dev);
> extern void pci_disable_enabled_device(struct pci_dev *dev);
> extern int pci_finish_runtime_suspend(struct pci_dev *dev);
> extern int __pci_pme_wakeup(struct pci_dev *dev, void *ign);
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] PCI / PM: Restore the original behavior of pci_set_power_state()
2012-07-05 21:29 ` Bjorn Helgaas
@ 2012-07-05 21:57 ` Rafael J. Wysocki
2012-07-05 22:31 ` Bjorn Helgaas
0 siblings, 1 reply; 4+ messages in thread
From: Rafael J. Wysocki @ 2012-07-05 21:57 UTC (permalink / raw)
To: Bjorn Helgaas
Cc: Jesse Barnes, Linux PM mailing list, LKML, Matthew Garrett,
linux-pci, Huang Ying
On Thursday, July 05, 2012, Bjorn Helgaas wrote:
> On Thu, Jun 28, 2012 at 4:01 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> > From: Rafael J. Wysocki <rjw@sisk.pl>
> >
> > Commit cc2893b6 (PCI: Ensure we re-enable devices on resume)
> > addressed the problem with USB not being powered after resume on
> > recent Lenovo machines, but it did that in a suboptimal way.
> > Namely, it should have changed the relevant code paths only,
> > which are pci_pm_resume_noirq() and pci_pm_restore_noirq() supposed
> > to restore the device's power and standard configuration registers
> > after system resume from suspend or hibernation. Instead, however,
> > it modified pci_set_power_state() which is executed in several
> > other situations too. That resulted in some undesirable effects,
> > like attempting to change a device's power state in the same way
> > multiple times in a row (up to as many as 4 times in a row in the
> > snd_hda_intel driver).
> >
> > Fix the bug addressed by commit cc2893b6 in an alternative way,
> > by forcibly powering up all devices in pci_pm_default_resume_early(),
> > which is called by pci_pm_resume_noirq() and pci_pm_restore_noirq()
> > to restore the device's power and standard configuration registers,
> > and modifying pci_pm_runtime_resume() to avoid the forcible power-up
> > if not necessary. Then, revert the changes made by commit cc2893b6
> > to make the confusion introduced by it go away.
> >
> > Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> > ---
> > drivers/pci/pci-driver.c | 14 ++++++++------
> > drivers/pci/pci.c | 19 ++++++++++++++++++-
> > drivers/pci/pci.h | 1 +
> > 3 files changed, 27 insertions(+), 7 deletions(-)
> >
> > Index: linux/drivers/pci/pci.c
> > ===================================================================
> > --- linux.orig/drivers/pci/pci.c
> > +++ linux/drivers/pci/pci.c
> > @@ -662,6 +662,19 @@ void pci_update_current_state(struct pci
> > }
> >
> > /**
> > + * pci_power_up - Put the given device into D0 forcibly
> > + * @dev: PCI device to power up
> > + */
> > +void pci_power_up(struct pci_dev *dev)
> > +{
> > + if (platform_pci_power_manageable(dev))
> > + platform_pci_set_power_state(dev, PCI_D0);
> > +
> > + pci_raw_set_power_state(dev, PCI_D0);
> > + pci_update_current_state(dev, PCI_D0);
> > +}
> > +
> > +/**
> > * pci_platform_power_transition - Use platform to change device power state
> > * @dev: PCI device to handle.
> > * @state: State to put the device into.
> > @@ -707,7 +720,7 @@ static void __pci_start_power_transition
> > */
> > int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
> > {
> > - return state >= PCI_D0 ?
> > + return state > PCI_D0 ?
> > pci_platform_power_transition(dev, state) : -EINVAL;
>
> This hunk conflicted with Huang's D3_COLD patches. I fixed it up; can
> you check and make sure I did it correctly?
>
> I pushed the resolution to here:
> git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git on the
> pci/rafael-pci_set_power_state-rebase branch.
Yes, it looks good. The point is to make __pci_complete_power_transition()
return the error code for PCI_DO too.
Thanks,
Rafael
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] PCI / PM: Restore the original behavior of pci_set_power_state()
2012-07-05 21:57 ` Rafael J. Wysocki
@ 2012-07-05 22:31 ` Bjorn Helgaas
0 siblings, 0 replies; 4+ messages in thread
From: Bjorn Helgaas @ 2012-07-05 22:31 UTC (permalink / raw)
To: Rafael J. Wysocki
Cc: Jesse Barnes, Linux PM mailing list, LKML, Matthew Garrett,
linux-pci, Huang Ying
On Thu, Jul 5, 2012 at 3:57 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> On Thursday, July 05, 2012, Bjorn Helgaas wrote:
>> On Thu, Jun 28, 2012 at 4:01 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
>> > From: Rafael J. Wysocki <rjw@sisk.pl>
>> >
>> > Commit cc2893b6 (PCI: Ensure we re-enable devices on resume)
>> > addressed the problem with USB not being powered after resume on
>> > recent Lenovo machines, but it did that in a suboptimal way.
>> > Namely, it should have changed the relevant code paths only,
>> > which are pci_pm_resume_noirq() and pci_pm_restore_noirq() supposed
>> > to restore the device's power and standard configuration registers
>> > after system resume from suspend or hibernation. Instead, however,
>> > it modified pci_set_power_state() which is executed in several
>> > other situations too. That resulted in some undesirable effects,
>> > like attempting to change a device's power state in the same way
>> > multiple times in a row (up to as many as 4 times in a row in the
>> > snd_hda_intel driver).
>> >
>> > Fix the bug addressed by commit cc2893b6 in an alternative way,
>> > by forcibly powering up all devices in pci_pm_default_resume_early(),
>> > which is called by pci_pm_resume_noirq() and pci_pm_restore_noirq()
>> > to restore the device's power and standard configuration registers,
>> > and modifying pci_pm_runtime_resume() to avoid the forcible power-up
>> > if not necessary. Then, revert the changes made by commit cc2893b6
>> > to make the confusion introduced by it go away.
>> >
>> > Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
>> > ---
>> > drivers/pci/pci-driver.c | 14 ++++++++------
>> > drivers/pci/pci.c | 19 ++++++++++++++++++-
>> > drivers/pci/pci.h | 1 +
>> > 3 files changed, 27 insertions(+), 7 deletions(-)
>> >
>> > Index: linux/drivers/pci/pci.c
>> > ===================================================================
>> > --- linux.orig/drivers/pci/pci.c
>> > +++ linux/drivers/pci/pci.c
>> > @@ -662,6 +662,19 @@ void pci_update_current_state(struct pci
>> > }
>> >
>> > /**
>> > + * pci_power_up - Put the given device into D0 forcibly
>> > + * @dev: PCI device to power up
>> > + */
>> > +void pci_power_up(struct pci_dev *dev)
>> > +{
>> > + if (platform_pci_power_manageable(dev))
>> > + platform_pci_set_power_state(dev, PCI_D0);
>> > +
>> > + pci_raw_set_power_state(dev, PCI_D0);
>> > + pci_update_current_state(dev, PCI_D0);
>> > +}
>> > +
>> > +/**
>> > * pci_platform_power_transition - Use platform to change device power state
>> > * @dev: PCI device to handle.
>> > * @state: State to put the device into.
>> > @@ -707,7 +720,7 @@ static void __pci_start_power_transition
>> > */
>> > int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
>> > {
>> > - return state >= PCI_D0 ?
>> > + return state > PCI_D0 ?
>> > pci_platform_power_transition(dev, state) : -EINVAL;
>>
>> This hunk conflicted with Huang's D3_COLD patches. I fixed it up; can
>> you check and make sure I did it correctly?
>>
>> I pushed the resolution to here:
>> git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git on the
>> pci/rafael-pci_set_power_state-rebase branch.
>
> Yes, it looks good. The point is to make __pci_complete_power_transition()
> return the error code for PCI_DO too.
Applied to my "next" branch and pushed, thanks a lot!
Bjorn
^ permalink raw reply [flat|nested] 4+ messages in thread
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2012-06-28 10:01 [PATCH] PCI / PM: Restore the original behavior of pci_set_power_state() Rafael J. Wysocki
2012-07-05 21:29 ` Bjorn Helgaas
2012-07-05 21:57 ` Rafael J. Wysocki
2012-07-05 22:31 ` Bjorn Helgaas
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