| Message ID | 1504018610-10822-7-git-send-email-ulf.hansson@linaro.org (mailing list archive) |
|---|---|
| State | Rejected, archived |
| Headers | show |
On Tuesday, August 29, 2017 4:56:48 PM CEST Ulf Hansson wrote: > This change enables the ACPI PM domain to cope with drivers that deploys > the runtime PM centric path for system sleep. [cut] > @@ -1052,11 +1066,20 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete); > * @dev: Device to handle. > * > * Follow PCI and resume devices suspended at run time before running their > - * system suspend callbacks. > + * system suspend callbacks. However, try to avoid it in case the runtime PM > + * centric path is used for the device and then trust the driver to do the > + * right thing. > */ > int acpi_subsys_suspend(struct device *dev) > { > - pm_runtime_resume(dev); > + struct acpi_device *adev = ACPI_COMPANION(dev); > + > + if (!adev) > + return 0; > + > + if (!dev_pm_is_rpm_sleep(dev) || acpi_dev_needs_resume(dev, adev)) > + pm_runtime_resume(dev); > + > return pm_generic_suspend(dev); > } > EXPORT_SYMBOL_GPL(acpi_subsys_suspend); Well, I tried to avoid calling acpi_dev_needs_resume() for multiple times and that's why I added the update_state thing. Moreover, the is_rpm_sleep flag here has to mean not only that direct_complete should not be used with the device, but also that its driver is fine with not resuming it. IMO it is not a good idea to use one flag for these two different things at the same time at all. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 29 August 2017 at 17:27, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > On Tuesday, August 29, 2017 4:56:48 PM CEST Ulf Hansson wrote: >> This change enables the ACPI PM domain to cope with drivers that deploys >> the runtime PM centric path for system sleep. > > [cut] > >> @@ -1052,11 +1066,20 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete); >> * @dev: Device to handle. >> * >> * Follow PCI and resume devices suspended at run time before running their >> - * system suspend callbacks. >> + * system suspend callbacks. However, try to avoid it in case the runtime PM >> + * centric path is used for the device and then trust the driver to do the >> + * right thing. >> */ >> int acpi_subsys_suspend(struct device *dev) >> { >> - pm_runtime_resume(dev); >> + struct acpi_device *adev = ACPI_COMPANION(dev); >> + >> + if (!adev) >> + return 0; >> + >> + if (!dev_pm_is_rpm_sleep(dev) || acpi_dev_needs_resume(dev, adev)) >> + pm_runtime_resume(dev); >> + >> return pm_generic_suspend(dev); >> } >> EXPORT_SYMBOL_GPL(acpi_subsys_suspend); > > Well, I tried to avoid calling acpi_dev_needs_resume() for multiple times > and that's why I added the update_state thing. > > Moreover, the is_rpm_sleep flag here has to mean not only that > direct_complete should not be used with the device, but also that its driver > is fine with not resuming it. Let me try to explain this better. I realize the changelog is misleading around this particular section! Huh, apologize for that! First, patch1 makes the PM core treat the is_rpm_sleep flag as the direct_complete isn't allowed for the device. For that reason, when the is_rpm_sleep is set, there is no point calling acpi_dev_needs_resume() from acpi_subsys_prepare(), but instead that can be deferred to acpi_subsys_suspend() - because it doesn't matter if acpi_subsys_prepare() returns 0 or 1, in either case the acpi_subsys_suspend() will be called. That's really what goes on here. The end result is the same. If the acpi_dev_needs_resume() thinks that the device needs to be runtime resumed, pm_runtime_resume() is called for the device in acpi_subsys_suspend(). So, this has nothing to do with whether the driver "is fine with not resuming it" thing. > > IMO it is not a good idea to use one flag for these two different things at the > same time at all. Yeah, I guess my upper comment addresses your immediate concern here? However, there is one other thing the is_rpm_flag means. That is that the driver has informed the ACPI PM domain, to trust the driver to deal with system sleep, via re-using the runtime PM callbacks. So the flag does still have two meanings, but that we can change - of course. > > Thanks, > Rafael > Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Friday, September 1, 2017 10:27:05 AM CEST Ulf Hansson wrote: > On 29 August 2017 at 17:27, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > > On Tuesday, August 29, 2017 4:56:48 PM CEST Ulf Hansson wrote: > >> This change enables the ACPI PM domain to cope with drivers that deploys > >> the runtime PM centric path for system sleep. > > > > [cut] > > > >> @@ -1052,11 +1066,20 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete); > >> * @dev: Device to handle. > >> * > >> * Follow PCI and resume devices suspended at run time before running their > >> - * system suspend callbacks. > >> + * system suspend callbacks. However, try to avoid it in case the runtime PM > >> + * centric path is used for the device and then trust the driver to do the > >> + * right thing. > >> */ > >> int acpi_subsys_suspend(struct device *dev) > >> { > >> - pm_runtime_resume(dev); > >> + struct acpi_device *adev = ACPI_COMPANION(dev); > >> + > >> + if (!adev) > >> + return 0; > >> + > >> + if (!dev_pm_is_rpm_sleep(dev) || acpi_dev_needs_resume(dev, adev)) > >> + pm_runtime_resume(dev); > >> + > >> return pm_generic_suspend(dev); > >> } > >> EXPORT_SYMBOL_GPL(acpi_subsys_suspend); > > > > Well, I tried to avoid calling acpi_dev_needs_resume() for multiple times > > and that's why I added the update_state thing. > > > > Moreover, the is_rpm_sleep flag here has to mean not only that > > direct_complete should not be used with the device, but also that its driver > > is fine with not resuming it. > > Let me try to explain this better. I realize the changelog is > misleading around this particular section! Huh, apologize for that! > > First, patch1 makes the PM core treat the is_rpm_sleep flag as the > direct_complete isn't allowed for the device. > > For that reason, when the is_rpm_sleep is set, there is no point > calling acpi_dev_needs_resume() from acpi_subsys_prepare(), but > instead that can be deferred to acpi_subsys_suspend() - because it > doesn't matter if acpi_subsys_prepare() returns 0 or 1, in either case > the acpi_subsys_suspend() will be called. That's really what goes on > here. > > The end result is the same. If the acpi_dev_needs_resume() thinks that > the device needs to be runtime resumed, pm_runtime_resume() is called > for the device in acpi_subsys_suspend(). > > So, this has nothing to do with whether the driver "is fine with not > resuming it" thing. No, sorry. If is_rpm_sleep was not set, the ACPI PM domain would resume the device in acpi_subsys_suspend() regardless of the acpi_dev_needs_resume() return value. That's what's there in the patch. So clearly, setting is_rpm_sleep means "this device does not need to be resumed in acpi_subsys_suspend() unless acpi_dev_needs_resume() returns true". Which clearly means that the driver *is* fine with not resuming it, because if is_rpm_sleep is set, the device in fact may not be resumed and then the driver will need to cope with that. And note that this meaning of is_rpm_sleep is different from what it is expected to mean to the core. > > > > IMO it is not a good idea to use one flag for these two different things at the > > same time at all. > > Yeah, I guess my upper comment addresses your immediate concern here? No, they don't. > However, there is one other thing the is_rpm_flag means. That is that > the driver has informed the ACPI PM domain, to trust the driver to > deal with system sleep, via re-using the runtime PM callbacks. > So the flag does still have two meanings, but that we can change - of course. I guess that you are referring to the use of dev_pm_is_rpm_sleep() in acpi_subsys_suspend_late()? That's the third thing this flag means ... Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2 September 2017 at 17:38, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > On Friday, September 1, 2017 10:27:05 AM CEST Ulf Hansson wrote: >> On 29 August 2017 at 17:27, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: >> > On Tuesday, August 29, 2017 4:56:48 PM CEST Ulf Hansson wrote: >> >> This change enables the ACPI PM domain to cope with drivers that deploys >> >> the runtime PM centric path for system sleep. >> > >> > [cut] >> > >> >> @@ -1052,11 +1066,20 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete); >> >> * @dev: Device to handle. >> >> * >> >> * Follow PCI and resume devices suspended at run time before running their >> >> - * system suspend callbacks. >> >> + * system suspend callbacks. However, try to avoid it in case the runtime PM >> >> + * centric path is used for the device and then trust the driver to do the >> >> + * right thing. >> >> */ >> >> int acpi_subsys_suspend(struct device *dev) >> >> { >> >> - pm_runtime_resume(dev); >> >> + struct acpi_device *adev = ACPI_COMPANION(dev); >> >> + >> >> + if (!adev) >> >> + return 0; >> >> + >> >> + if (!dev_pm_is_rpm_sleep(dev) || acpi_dev_needs_resume(dev, adev)) >> >> + pm_runtime_resume(dev); >> >> + >> >> return pm_generic_suspend(dev); >> >> } >> >> EXPORT_SYMBOL_GPL(acpi_subsys_suspend); >> > >> > Well, I tried to avoid calling acpi_dev_needs_resume() for multiple times >> > and that's why I added the update_state thing. >> > >> > Moreover, the is_rpm_sleep flag here has to mean not only that >> > direct_complete should not be used with the device, but also that its driver >> > is fine with not resuming it. >> >> Let me try to explain this better. I realize the changelog is >> misleading around this particular section! Huh, apologize for that! >> >> First, patch1 makes the PM core treat the is_rpm_sleep flag as the >> direct_complete isn't allowed for the device. >> >> For that reason, when the is_rpm_sleep is set, there is no point >> calling acpi_dev_needs_resume() from acpi_subsys_prepare(), but >> instead that can be deferred to acpi_subsys_suspend() - because it >> doesn't matter if acpi_subsys_prepare() returns 0 or 1, in either case >> the acpi_subsys_suspend() will be called. That's really what goes on >> here. >> >> The end result is the same. If the acpi_dev_needs_resume() thinks that >> the device needs to be runtime resumed, pm_runtime_resume() is called >> for the device in acpi_subsys_suspend(). >> >> So, this has nothing to do with whether the driver "is fine with not >> resuming it" thing. > > No, sorry. > > If is_rpm_sleep was not set, the ACPI PM domain would resume the device in > acpi_subsys_suspend() regardless of the acpi_dev_needs_resume() return value. Yes, I believe I forgot about one scenario, when the direct_complete path has been abandoned by the PM core, because a child device was suspend before and it couldn't run the direct_complete path for it? Just to be sure, that's the case you also had in mind? > That's what's there in the patch. So clearly, setting is_rpm_sleep means > "this device does not need to be resumed in acpi_subsys_suspend() unless > acpi_dev_needs_resume() returns true". Which clearly means that the driver > *is* fine with not resuming it, because if is_rpm_sleep is set, the device > in fact may not be resumed and then the driver will need to cope with that. Yes, I understand your concern, because we may break the default behavior of the ACPI PM domain. So, *if* there will be a next version, I will make sure to be better safe than sorry, and add one flag per use case. > > And note that this meaning of is_rpm_sleep is different from what it is > expected to mean to the core. > >> > >> > IMO it is not a good idea to use one flag for these two different things at the >> > same time at all. >> >> Yeah, I guess my upper comment addresses your immediate concern here? > > No, they don't. > >> However, there is one other thing the is_rpm_flag means. That is that >> the driver has informed the ACPI PM domain, to trust the driver to >> deal with system sleep, via re-using the runtime PM callbacks. >> So the flag does still have two meanings, but that we can change - of course. > > I guess that you are referring to the use of dev_pm_is_rpm_sleep() in > acpi_subsys_suspend_late()? That's the third thing this flag means ... Yes. Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Monday, September 4, 2017 3:21:15 PM CEST Ulf Hansson wrote: > On 2 September 2017 at 17:38, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > > On Friday, September 1, 2017 10:27:05 AM CEST Ulf Hansson wrote: > >> On 29 August 2017 at 17:27, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > >> > On Tuesday, August 29, 2017 4:56:48 PM CEST Ulf Hansson wrote: > >> >> This change enables the ACPI PM domain to cope with drivers that deploys > >> >> the runtime PM centric path for system sleep. > >> > > >> > [cut] > >> > > >> >> @@ -1052,11 +1066,20 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete); > >> >> * @dev: Device to handle. > >> >> * > >> >> * Follow PCI and resume devices suspended at run time before running their > >> >> - * system suspend callbacks. > >> >> + * system suspend callbacks. However, try to avoid it in case the runtime PM > >> >> + * centric path is used for the device and then trust the driver to do the > >> >> + * right thing. > >> >> */ > >> >> int acpi_subsys_suspend(struct device *dev) > >> >> { > >> >> - pm_runtime_resume(dev); > >> >> + struct acpi_device *adev = ACPI_COMPANION(dev); > >> >> + > >> >> + if (!adev) > >> >> + return 0; > >> >> + > >> >> + if (!dev_pm_is_rpm_sleep(dev) || acpi_dev_needs_resume(dev, adev)) > >> >> + pm_runtime_resume(dev); > >> >> + > >> >> return pm_generic_suspend(dev); > >> >> } > >> >> EXPORT_SYMBOL_GPL(acpi_subsys_suspend); > >> > > >> > Well, I tried to avoid calling acpi_dev_needs_resume() for multiple times > >> > and that's why I added the update_state thing. > >> > > >> > Moreover, the is_rpm_sleep flag here has to mean not only that > >> > direct_complete should not be used with the device, but also that its driver > >> > is fine with not resuming it. > >> > >> Let me try to explain this better. I realize the changelog is > >> misleading around this particular section! Huh, apologize for that! > >> > >> First, patch1 makes the PM core treat the is_rpm_sleep flag as the > >> direct_complete isn't allowed for the device. > >> > >> For that reason, when the is_rpm_sleep is set, there is no point > >> calling acpi_dev_needs_resume() from acpi_subsys_prepare(), but > >> instead that can be deferred to acpi_subsys_suspend() - because it > >> doesn't matter if acpi_subsys_prepare() returns 0 or 1, in either case > >> the acpi_subsys_suspend() will be called. That's really what goes on > >> here. > >> > >> The end result is the same. If the acpi_dev_needs_resume() thinks that > >> the device needs to be runtime resumed, pm_runtime_resume() is called > >> for the device in acpi_subsys_suspend(). > >> > >> So, this has nothing to do with whether the driver "is fine with not > >> resuming it" thing. > > > > No, sorry. > > > > If is_rpm_sleep was not set, the ACPI PM domain would resume the device in > > acpi_subsys_suspend() regardless of the acpi_dev_needs_resume() return value. > > Yes, I believe I forgot about one scenario, when the direct_complete > path has been abandoned by the PM core, because a child device was > suspend before and it couldn't run the direct_complete path for it? > > Just to be sure, that's the case you also had in mind? Yes. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c index e726173..2e34f69 100644 --- a/drivers/acpi/acpi_lpss.c +++ b/drivers/acpi/acpi_lpss.c @@ -732,7 +732,7 @@ static int acpi_lpss_suspend_late(struct device *dev) int ret; ret = pm_generic_suspend_late(dev); - if (ret) + if (ret || dev_pm_is_rpm_sleep(dev)) return ret; return lpss_suspend_late(dev); @@ -757,13 +757,22 @@ static int lpss_resume_early(struct device *dev) static int acpi_lpss_resume_early(struct device *dev) { - int ret; + int ret = 0; - ret = lpss_resume_early(dev); - if (ret) - return ret; + if (!dev_pm_is_rpm_sleep(dev)) + ret = lpss_resume_early(dev); - return pm_generic_resume_early(dev); + return ret ? ret : pm_generic_resume_early(dev); +} +#else +static inline int lpss_suspend_late(struct device *dev) +{ + return 0; +} + +static inline int lpss_resume_early(struct device *dev) +{ + return 0; } #endif /* CONFIG_PM_SLEEP */ @@ -861,6 +870,9 @@ static int acpi_lpss_runtime_suspend(struct device *dev) if (ret) return ret; + if (!pm_runtime_enabled(dev)) + return lpss_suspend_late(dev); + if (pdata->dev_desc->flags & LPSS_SAVE_CTX) acpi_lpss_save_ctx(dev, pdata); @@ -882,21 +894,29 @@ static int acpi_lpss_runtime_resume(struct device *dev) struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); int ret; - /* - * This call is kept first to be in symmetry with - * acpi_lpss_runtime_suspend() one. - */ - if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available()) - lpss_iosf_exit_d3_state(); + if (pm_runtime_enabled(dev)) { + /* + * This call is kept first to be in symmetry with + * acpi_lpss_runtime_suspend() one. + */ + if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && + iosf_mbi_available()) + lpss_iosf_exit_d3_state(); - ret = acpi_dev_runtime_resume(dev); - if (ret) - return ret; + ret = acpi_dev_runtime_resume(dev); + if (ret) + return ret; - acpi_lpss_d3_to_d0_delay(pdata); + acpi_lpss_d3_to_d0_delay(pdata); - if (pdata->dev_desc->flags & LPSS_SAVE_CTX) - acpi_lpss_restore_ctx(dev, pdata); + if (pdata->dev_desc->flags & LPSS_SAVE_CTX) + acpi_lpss_restore_ctx(dev, pdata); + + } else { + ret = lpss_resume_early(dev); + if (ret) + return ret; + } return pm_generic_runtime_resume(dev); } diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 5181057..f5c4d0e 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -913,7 +913,14 @@ EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume); int acpi_subsys_runtime_suspend(struct device *dev) { int ret = pm_generic_runtime_suspend(dev); - return ret ? ret : acpi_dev_runtime_suspend(dev); + + if (ret) + return ret; + + if (!pm_runtime_enabled(dev)) + return acpi_dev_suspend_late(dev); + + return acpi_dev_runtime_suspend(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend); @@ -926,7 +933,13 @@ EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend); */ int acpi_subsys_runtime_resume(struct device *dev) { - int ret = acpi_dev_runtime_resume(dev); + int ret = 0; + + if (!pm_runtime_enabled(dev)) + ret = acpi_dev_resume_early(dev); + else + ret = acpi_dev_runtime_resume(dev); + return ret ? ret : pm_generic_runtime_resume(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume); @@ -1023,7 +1036,7 @@ int acpi_subsys_prepare(struct device *dev) if (ret < 0) return ret; - if (!adev || !pm_runtime_suspended(dev)) + if (!adev || dev_pm_is_rpm_sleep(dev) || !pm_runtime_suspended(dev)) return 0; return !acpi_dev_needs_resume(dev, adev); @@ -1042,7 +1055,8 @@ void acpi_subsys_complete(struct device *dev) * the sleep state it is going out of and it has never been resumed till * now, resume it in case the firmware powered it up. */ - if (dev->power.direct_complete && pm_resume_via_firmware()) + if ((dev->power.direct_complete || dev_pm_is_rpm_sleep(dev)) && + pm_resume_via_firmware()) pm_request_resume(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_complete); @@ -1052,11 +1066,20 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete); * @dev: Device to handle. * * Follow PCI and resume devices suspended at run time before running their - * system suspend callbacks. + * system suspend callbacks. However, try to avoid it in case the runtime PM + * centric path is used for the device and then trust the driver to do the + * right thing. */ int acpi_subsys_suspend(struct device *dev) { - pm_runtime_resume(dev); + struct acpi_device *adev = ACPI_COMPANION(dev); + + if (!adev) + return 0; + + if (!dev_pm_is_rpm_sleep(dev) || acpi_dev_needs_resume(dev, adev)) + pm_runtime_resume(dev); + return pm_generic_suspend(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_suspend); @@ -1071,7 +1094,11 @@ EXPORT_SYMBOL_GPL(acpi_subsys_suspend); int acpi_subsys_suspend_late(struct device *dev) { int ret = pm_generic_suspend_late(dev); - return ret ? ret : acpi_dev_suspend_late(dev); + + if (ret || dev_pm_is_rpm_sleep(dev)) + return ret; + + return acpi_dev_suspend_late(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late); @@ -1085,7 +1112,11 @@ EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late); */ int acpi_subsys_resume_early(struct device *dev) { - int ret = acpi_dev_resume_early(dev); + int ret = 0; + + if (!dev_pm_is_rpm_sleep(dev)) + ret = acpi_dev_resume_early(dev); + return ret ? ret : pm_generic_resume_early(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_resume_early); @@ -1096,13 +1127,21 @@ EXPORT_SYMBOL_GPL(acpi_subsys_resume_early); */ int acpi_subsys_freeze(struct device *dev) { + struct acpi_device *adev = ACPI_COMPANION(dev); + + if (!adev) + return 0; + /* * This used to be done in acpi_subsys_prepare() for all devices and * some drivers may depend on it, so do it here. Ideally, however, * runtime-suspended devices should not be touched during freeze/thaw - * transitions. + * transitions. In case the runtime PM centric path is used, let's try + * to avoid it. */ - pm_runtime_resume(dev); + if (!dev_pm_is_rpm_sleep(dev) || acpi_dev_needs_resume(dev, adev)) + pm_runtime_resume(dev); + return pm_generic_freeze(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
This change enables the ACPI PM domain to cope with drivers that deploys the runtime PM centric path for system sleep. Currently the ACPI PM domain supports the direct_complete path, which offers some nice optimizations from PM point of view during system sleep. However, the runtime PM centric path have some additional optimizations that this change enables for the ACPI PM domain. Let's walk through them. *) The runtime PM centric path, doesn't require the device to be runtime suspended during system suspend, when later during system resume trying to avoid to bring it back into full power. That is the case for the direct_complete path. This further avoids wasting power during system resume, but should also decrease the time it takes to resume the device. **) When the runtime PM centric path is used, the PM core does not skip calling any system sleep callbacks for the device, which is the case in the direct_complete path. Based on that knowledge and relying on the driver to do the right thing, the ACPI PM domain may avoid to always runtime resume the device in the device_suspend() phase. ***) In the runtime PM centric path, the device may remain runtime PM enabled until the device_suspend_late() phase, instead of as in the direct_complete path, in the device_suspend() phase. This is convenient if the device needs to be runtime resumed sometime during the device_suspend() phase. To deploy the runtime PM centric approach for the ACPI PM domain, and make it benefit from the above optimizations, the follow changes are made. First, the ACPI PM domain's runtime PM callbacks may be called when runtime PM has been disabled for the device. This serves as an indication to understand when they are running in the system sleep sequence, instead of in the regular runtime PM path. For these cases, make the ACPI PM domain to execute the same operations as normally being run, when the ->suspend_late() and the ->resume_early() callbacks are invoked. Second, the ACPI PM domain's ->suspend_late() callback, shall not execute the regular operations to put the device into low power state, when the runtime PM centric path is used. Calling pm_generic_suspend_late() is sufficient. Vice verse applies to the ACPI PM domain's ->resume_early() callback. Third, in the ACPI PM domain's ->suspend|freeze() callbacks, let's avoid runtime resuming the device in case the runtime PM centric path is used, unless there are ACPI PM domain specific reasons to not. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> --- Changes in v3: - Convert to use the PM core flag, is_rpm_sleep flag. - Fold in changes from patch v2 7/9, which means avoiding to runtime resume the device in the ACPI PM domain's ->suspend|freeze() callbacks. - Updated changelog to reflect new changes. --- drivers/acpi/acpi_lpss.c | 56 ++++++++++++++++++++++++++++++--------------- drivers/acpi/device_pm.c | 59 ++++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 87 insertions(+), 28 deletions(-)