diff mbox

[1/3] PCI / PM: Skip bridges in pci_enable_wake()

Message ID 1895122.yvmCHzQO3z@aspire.rjw.lan (mailing list archive)
State Mainlined
Delegated to: Rafael Wysocki
Headers show

Commit Message

Rafael J. Wysocki July 21, 2017, 12:38 p.m. UTC
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI bridges only have a reason to generate wakeup signals on behalf
of devices below them, so avoid preparing bridges for wakeup directly
in pci_enable_wake().

Also drop the pci_has_subordinate() check from pci_pm_default_resume()
as this will be done by pci_enable_wake() itself now.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/pci/pci-driver.c |    4 +---
 drivers/pci/pci.c        |    7 +++++++
 2 files changed, 8 insertions(+), 3 deletions(-)

Comments

Mika Westerberg July 25, 2017, 12:44 p.m. UTC | #1
On Fri, Jul 21, 2017 at 02:38:08PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> PCI bridges only have a reason to generate wakeup signals on behalf
> of devices below them, so avoid preparing bridges for wakeup directly
> in pci_enable_wake().
> 
> Also drop the pci_has_subordinate() check from pci_pm_default_resume()
> as this will be done by pci_enable_wake() itself now.
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Bjorn Helgaas July 31, 2017, 8:53 p.m. UTC | #2
On Fri, Jul 21, 2017 at 02:38:08PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> PCI bridges only have a reason to generate wakeup signals on behalf
> of devices below them, so avoid preparing bridges for wakeup directly
> in pci_enable_wake().
> 
> Also drop the pci_has_subordinate() check from pci_pm_default_resume()
> as this will be done by pci_enable_wake() itself now.
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>

> ---
>  drivers/pci/pci-driver.c |    4 +---
>  drivers/pci/pci.c        |    7 +++++++
>  2 files changed, 8 insertions(+), 3 deletions(-)
> 
> Index: linux-pm/drivers/pci/pci.c
> ===================================================================
> --- linux-pm.orig/drivers/pci/pci.c
> +++ linux-pm/drivers/pci/pci.c
> @@ -1909,6 +1909,13 @@ int pci_enable_wake(struct pci_dev *dev,
>  {
>  	int ret = 0;
>  
> +	/*
> +	 * Bridges can only signal wakeup on behalf of subordinate devices,
> +	 * but that is set up elsewhere, so skip them.

A specific pointer to this "elsewhere" would be useful here.

> +	 */
> +	if (pci_has_subordinate(dev))
> +		return 0;
> +
>  	/* Don't do the same thing twice in a row for one device. */
>  	if (!!enable == !!dev->wakeup_prepared)
>  		return 0;
> Index: linux-pm/drivers/pci/pci-driver.c
> ===================================================================
> --- linux-pm.orig/drivers/pci/pci-driver.c
> +++ linux-pm/drivers/pci/pci-driver.c
> @@ -642,9 +642,7 @@ static int pci_legacy_resume(struct devi
>  static void pci_pm_default_resume(struct pci_dev *pci_dev)
>  {
>  	pci_fixup_device(pci_fixup_resume, pci_dev);
> -
> -	if (!pci_has_subordinate(pci_dev))
> -		pci_enable_wake(pci_dev, PCI_D0, false);
> +	pci_enable_wake(pci_dev, PCI_D0, false);
>  }
>  
>  static void pci_pm_default_suspend(struct pci_dev *pci_dev)
>
Rafael J. Wysocki July 31, 2017, 8:59 p.m. UTC | #3
On Mon, Jul 31, 2017 at 10:53 PM, Bjorn Helgaas <helgaas@kernel.org> wrote:
> On Fri, Jul 21, 2017 at 02:38:08PM +0200, Rafael J. Wysocki wrote:
>> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>>
>> PCI bridges only have a reason to generate wakeup signals on behalf
>> of devices below them, so avoid preparing bridges for wakeup directly
>> in pci_enable_wake().
>>
>> Also drop the pci_has_subordinate() check from pci_pm_default_resume()
>> as this will be done by pci_enable_wake() itself now.
>>
>> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Acked-by: Bjorn Helgaas <bhelgaas@google.com>

Thanks!

>> ---
>>  drivers/pci/pci-driver.c |    4 +---
>>  drivers/pci/pci.c        |    7 +++++++
>>  2 files changed, 8 insertions(+), 3 deletions(-)
>>
>> Index: linux-pm/drivers/pci/pci.c
>> ===================================================================
>> --- linux-pm.orig/drivers/pci/pci.c
>> +++ linux-pm/drivers/pci/pci.c
>> @@ -1909,6 +1909,13 @@ int pci_enable_wake(struct pci_dev *dev,
>>  {
>>       int ret = 0;
>>
>> +     /*
>> +      * Bridges can only signal wakeup on behalf of subordinate devices,
>> +      * but that is set up elsewhere, so skip them.
>
> A specific pointer to this "elsewhere" would be useful here.

OK
diff mbox

Patch

Index: linux-pm/drivers/pci/pci.c
===================================================================
--- linux-pm.orig/drivers/pci/pci.c
+++ linux-pm/drivers/pci/pci.c
@@ -1909,6 +1909,13 @@  int pci_enable_wake(struct pci_dev *dev,
 {
 	int ret = 0;
 
+	/*
+	 * Bridges can only signal wakeup on behalf of subordinate devices,
+	 * but that is set up elsewhere, so skip them.
+	 */
+	if (pci_has_subordinate(dev))
+		return 0;
+
 	/* Don't do the same thing twice in a row for one device. */
 	if (!!enable == !!dev->wakeup_prepared)
 		return 0;
Index: linux-pm/drivers/pci/pci-driver.c
===================================================================
--- linux-pm.orig/drivers/pci/pci-driver.c
+++ linux-pm/drivers/pci/pci-driver.c
@@ -642,9 +642,7 @@  static int pci_legacy_resume(struct devi
 static void pci_pm_default_resume(struct pci_dev *pci_dev)
 {
 	pci_fixup_device(pci_fixup_resume, pci_dev);
-
-	if (!pci_has_subordinate(pci_dev))
-		pci_enable_wake(pci_dev, PCI_D0, false);
+	pci_enable_wake(pci_dev, PCI_D0, false);
 }
 
 static void pci_pm_default_suspend(struct pci_dev *pci_dev)