From: Rafael J. Wysocki <rjw@xxxxxxx> Subject: PCI: Rework default handling of suspend and resume 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@xxxxxxx> --- drivers/pci/pci-driver.c | 90 ++++++++++++++++++++++++++++++----------------- 1 file changed, 59 insertions(+), 31 deletions(-) Index: linux-2.6/drivers/pci/pci-driver.c =================================================================== --- linux-2.6.orig/drivers/pci/pci-driver.c +++ linux-2.6/drivers/pci/pci-driver.c @@ -300,6 +300,14 @@ static void pci_device_shutdown(struct d #ifdef CONFIG_PM_SLEEP +static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev) +{ + struct pci_driver *drv = pci_dev->driver; + + return drv && (drv->suspend || drv->suspend_late || drv->resume + || drv->resume_early); +} + /* * Default "suspend" method for devices that have no driver provided suspend, * or not even a driver at all. @@ -317,14 +325,22 @@ static void pci_default_pm_suspend(struc /* * Default "resume" method for devices that have no driver provided resume, - * or not even a driver at all. + * or not even a driver at all (first part). */ -static int pci_default_pm_resume(struct pci_dev *pci_dev) +static void pci_default_pm_resume_early(struct pci_dev *pci_dev) { - int retval = 0; - /* restore the PCI config space */ pci_restore_state(pci_dev); +} + +/* + * Default "resume" method for devices that have no driver provided resume, + * or not even a driver at all (second part). + */ +static int pci_default_pm_resume_late(struct pci_dev *pci_dev) +{ + int retval; + /* if the device was enabled before suspend, reenable */ retval = pci_reenable_device(pci_dev); /* @@ -371,10 +387,12 @@ static int pci_legacy_resume(struct devi struct pci_dev * pci_dev = to_pci_dev(dev); struct pci_driver * drv = pci_dev->driver; - if (drv && drv->resume) + if (drv && drv->resume) { error = drv->resume(pci_dev); - else - error = pci_default_pm_resume(pci_dev); + } else { + pci_default_pm_resume_early(pci_dev); + error = pci_default_pm_resume_late(pci_dev); + } return error; } @@ -420,10 +438,8 @@ static int pci_pm_suspend(struct device if (drv->pm->suspend) { error = drv->pm->suspend(dev); suspend_report_result(drv->pm->suspend, error); - } else { - pci_default_pm_suspend(pci_dev); } - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_suspend(dev, PMSG_SUSPEND); } pci_fixup_device(pci_fixup_suspend, pci_dev); @@ -442,8 +458,10 @@ static int pci_pm_suspend_noirq(struct d error = drv->pm->suspend_noirq(dev); suspend_report_result(drv->pm->suspend_noirq, error); } - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_suspend_late(dev, PMSG_SUSPEND); + } else { + pci_default_pm_suspend(pci_dev); } return error; @@ -453,15 +471,17 @@ static int pci_pm_resume(struct device * { struct pci_dev *pci_dev = to_pci_dev(dev); struct device_driver *drv = dev->driver; - int error; + int error = 0; pci_fixup_device(pci_fixup_resume, pci_dev); if (drv && drv->pm) { - error = drv->pm->resume ? drv->pm->resume(dev) : - pci_default_pm_resume(pci_dev); - } else { + if (drv->pm->resume) + error = drv->pm->resume(dev); + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_resume(dev); + } else { + error = pci_default_pm_resume_late(pci_dev); } return error; @@ -478,8 +498,10 @@ static int pci_pm_resume_noirq(struct de if (drv && drv->pm) { if (drv->pm->resume_noirq) error = drv->pm->resume_noirq(dev); - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_resume_early(dev); + } else { + pci_default_pm_resume_early(pci_dev); } return error; @@ -506,10 +528,8 @@ static int pci_pm_freeze(struct device * if (drv->pm->freeze) { error = drv->pm->freeze(dev); suspend_report_result(drv->pm->freeze, error); - } else { - pci_default_pm_suspend(pci_dev); } - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_suspend(dev, PMSG_FREEZE); pci_fixup_device(pci_fixup_suspend, pci_dev); } @@ -528,8 +548,10 @@ static int pci_pm_freeze_noirq(struct de error = drv->pm->freeze_noirq(dev); suspend_report_result(drv->pm->freeze_noirq, error); } - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_suspend_late(dev, PMSG_FREEZE); + } else { + pci_default_pm_suspend(pci_dev); } return error; @@ -537,14 +559,15 @@ static int pci_pm_freeze_noirq(struct de static int pci_pm_thaw(struct device *dev) { + struct pci_dev *pci_dev = to_pci_dev(dev); struct device_driver *drv = dev->driver; int error = 0; if (drv && drv->pm) { if (drv->pm->thaw) error = drv->pm->thaw(dev); - } else { - pci_fixup_device(pci_fixup_resume, to_pci_dev(dev)); + } else if (pci_has_legacy_pm_support(pci_dev)) { + pci_fixup_device(pci_fixup_resume, pci_dev); error = pci_legacy_resume(dev); } @@ -560,7 +583,7 @@ static int pci_pm_thaw_noirq(struct devi if (drv && drv->pm) { if (drv->pm->thaw_noirq) error = drv->pm->thaw_noirq(dev); - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { pci_fixup_device(pci_fixup_resume_early, pci_dev); error = pci_legacy_resume_early(dev); } @@ -570,17 +593,18 @@ static int pci_pm_thaw_noirq(struct devi static int pci_pm_poweroff(struct device *dev) { + struct pci_dev *pci_dev = to_pci_dev(dev); struct device_driver *drv = dev->driver; int error = 0; - pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev)); + pci_fixup_device(pci_fixup_suspend, pci_dev); if (drv && drv->pm) { if (drv->pm->poweroff) { error = drv->pm->poweroff(dev); suspend_report_result(drv->pm->poweroff, error); } - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_suspend(dev, PMSG_HIBERNATE); } @@ -598,7 +622,7 @@ static int pci_pm_poweroff_noirq(struct error = drv->pm->poweroff_noirq(dev); suspend_report_result(drv->pm->poweroff_noirq, error); } - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_suspend_late(dev, PMSG_HIBERNATE); } @@ -609,13 +633,15 @@ static int pci_pm_restore(struct device { struct pci_dev *pci_dev = to_pci_dev(dev); struct device_driver *drv = dev->driver; - int error; + int error = 0; if (drv && drv->pm) { - error = drv->pm->restore ? drv->pm->restore(dev) : - pci_default_pm_resume(pci_dev); - } else { + if (drv->pm->restore) + error = drv->pm->restore(dev); + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_resume(dev); + } else { + error = pci_default_pm_resume_late(pci_dev); } pci_fixup_device(pci_fixup_resume, pci_dev); @@ -633,8 +659,10 @@ static int pci_pm_restore_noirq(struct d if (drv && drv->pm) { if (drv->pm->restore_noirq) error = drv->pm->restore_noirq(dev); - } else { + } else if (pci_has_legacy_pm_support(pci_dev)) { error = pci_legacy_resume_early(dev); + } else { + pci_default_pm_resume_early(pci_dev); } pci_fixup_device(pci_fixup_resume_early, pci_dev); _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
