diff options
Diffstat (limited to 'drivers/acpi/device_pm.c')
| -rw-r--r-- | drivers/acpi/device_pm.c | 165 |
1 files changed, 111 insertions, 54 deletions
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index e54956ae93d3..28cffaaf9d82 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -45,6 +45,19 @@ const char *acpi_power_state_string(int state) } } +static int acpi_dev_pm_explicit_get(struct acpi_device *device, int *state) +{ + unsigned long long psc; + acpi_status status; + + status = acpi_evaluate_integer(device->handle, "_PSC", NULL, &psc); + if (ACPI_FAILURE(status)) + return -ENODEV; + + *state = psc; + return 0; +} + /** * acpi_device_get_power - Get power state of an ACPI device. * @device: Device to get the power state of. @@ -53,10 +66,16 @@ const char *acpi_power_state_string(int state) * This function does not update the device's power.state field, but it may * update its parent's power.state field (when the parent's power state is * unknown and the device's power state turns out to be D0). + * + * Also, it does not update power resource reference counters to ensure that + * the power state returned by it will be persistent and it may return a power + * state shallower than previously set by acpi_device_set_power() for @device + * (if that power state depends on any power resources). */ int acpi_device_get_power(struct acpi_device *device, int *state) { int result = ACPI_STATE_UNKNOWN; + int error; if (!device || !state) return -EINVAL; @@ -73,18 +92,16 @@ int acpi_device_get_power(struct acpi_device *device, int *state) * if available. */ if (device->power.flags.power_resources) { - int error = acpi_power_get_inferred_state(device, &result); + error = acpi_power_get_inferred_state(device, &result); if (error) return error; } if (device->power.flags.explicit_get) { - acpi_handle handle = device->handle; - unsigned long long psc; - acpi_status status; + int psc; - status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc); - if (ACPI_FAILURE(status)) - return -ENODEV; + error = acpi_dev_pm_explicit_get(device, &psc); + if (error) + return error; /* * The power resources settings may indicate a power state @@ -118,7 +135,6 @@ int acpi_device_get_power(struct acpi_device *device, int *state) return 0; } -EXPORT_SYMBOL(acpi_device_get_power); static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state) { @@ -152,7 +168,8 @@ int acpi_device_set_power(struct acpi_device *device, int state) /* Make sure this is a valid target state */ - if (state == device->power.state) { + /* There is a special case for D0 addressed below. */ + if (state > ACPI_STATE_D0 && state == device->power.state) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n", device->pnp.bus_id, acpi_power_state_string(state))); @@ -202,9 +219,15 @@ int acpi_device_set_power(struct acpi_device *device, int state) return -ENODEV; } - result = acpi_dev_pm_explicit_set(device, state); - if (result) - goto end; + /* + * If the device goes from D3hot to D3cold, _PS3 has been + * evaluated for it already, so skip it in that case. + */ + if (device->power.state < ACPI_STATE_D3_HOT) { + result = acpi_dev_pm_explicit_set(device, state); + if (result) + goto end; + } if (device->power.flags.power_resources) result = acpi_power_transition(device, target_state); @@ -214,6 +237,30 @@ int acpi_device_set_power(struct acpi_device *device, int state) if (result) goto end; } + + if (device->power.state == ACPI_STATE_D0) { + int psc; + + /* Nothing to do here if _PSC is not present. */ + if (!device->power.flags.explicit_get) + return 0; + + /* + * The power state of the device was set to D0 last + * time, but that might have happened before a + * system-wide transition involving the platform + * firmware, so it may be necessary to evaluate _PS0 + * for the device here. However, use extra care here + * and evaluate _PSC to check the device's current power + * state, and only invoke _PS0 if the evaluation of _PSC + * is successful and it returns a power state different + * from D0. + */ + result = acpi_dev_pm_explicit_get(device, &psc); + if (result || psc == ACPI_STATE_D0) + return 0; + } + result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); } @@ -1073,7 +1120,7 @@ EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq); * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback. * @dev: Device to handle. */ -int acpi_subsys_resume_noirq(struct device *dev) +static int acpi_subsys_resume_noirq(struct device *dev) { if (dev_pm_may_skip_resume(dev)) return 0; @@ -1088,7 +1135,6 @@ int acpi_subsys_resume_noirq(struct device *dev) return pm_generic_resume_noirq(dev); } -EXPORT_SYMBOL_GPL(acpi_subsys_resume_noirq); /** * acpi_subsys_resume_early - Resume device using ACPI. @@ -1098,12 +1144,11 @@ EXPORT_SYMBOL_GPL(acpi_subsys_resume_noirq); * generic early resume procedure for it during system transition into the * working state. */ -int acpi_subsys_resume_early(struct device *dev) +static int acpi_subsys_resume_early(struct device *dev) { int ret = acpi_dev_resume(dev); return ret ? ret : pm_generic_resume_early(dev); } -EXPORT_SYMBOL_GPL(acpi_subsys_resume_early); /** * acpi_subsys_freeze - Run the device driver's freeze callback. @@ -1112,65 +1157,81 @@ EXPORT_SYMBOL_GPL(acpi_subsys_resume_early); int acpi_subsys_freeze(struct device *dev) { /* - * 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. + * Resume all runtime-suspended devices before creating a snapshot + * image of system memory, because the restore kernel generally cannot + * be expected to always handle them consistently and they need to be + * put into the runtime-active metastate during system resume anyway, + * so it is better to ensure that the state saved in the image will be + * always consistent with that. */ - if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND)) - pm_runtime_resume(dev); + pm_runtime_resume(dev); return pm_generic_freeze(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_freeze); /** - * acpi_subsys_freeze_late - Run the device driver's "late" freeze callback. - * @dev: Device to handle. + * acpi_subsys_restore_early - Restore device using ACPI. + * @dev: Device to restore. */ -int acpi_subsys_freeze_late(struct device *dev) +int acpi_subsys_restore_early(struct device *dev) { + int ret = acpi_dev_resume(dev); + return ret ? ret : pm_generic_restore_early(dev); +} +EXPORT_SYMBOL_GPL(acpi_subsys_restore_early); - if (dev_pm_smart_suspend_and_suspended(dev)) - return 0; +/** + * acpi_subsys_poweroff - Run the device driver's poweroff callback. + * @dev: Device to handle. + * + * Follow PCI and resume devices from runtime suspend before running their + * system poweroff callbacks, unless the driver can cope with runtime-suspended + * devices during system suspend and there are no ACPI-specific reasons for + * resuming them. + */ +int acpi_subsys_poweroff(struct device *dev) +{ + if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) || + acpi_dev_needs_resume(dev, ACPI_COMPANION(dev))) + pm_runtime_resume(dev); - return pm_generic_freeze_late(dev); + return pm_generic_poweroff(dev); } -EXPORT_SYMBOL_GPL(acpi_subsys_freeze_late); +EXPORT_SYMBOL_GPL(acpi_subsys_poweroff); /** - * acpi_subsys_freeze_noirq - Run the device driver's "noirq" freeze callback. + * acpi_subsys_poweroff_late - Run the device driver's poweroff callback. * @dev: Device to handle. + * + * Carry out the generic late poweroff procedure for @dev and use ACPI to put + * it into a low-power state during system transition into a sleep state. */ -int acpi_subsys_freeze_noirq(struct device *dev) +static int acpi_subsys_poweroff_late(struct device *dev) { + int ret; if (dev_pm_smart_suspend_and_suspended(dev)) return 0; - return pm_generic_freeze_noirq(dev); + ret = pm_generic_poweroff_late(dev); + if (ret) + return ret; + + return acpi_dev_suspend(dev, device_may_wakeup(dev)); } -EXPORT_SYMBOL_GPL(acpi_subsys_freeze_noirq); /** - * acpi_subsys_thaw_noirq - Run the device driver's "noirq" thaw callback. - * @dev: Device to handle. + * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback. + * @dev: Device to suspend. */ -int acpi_subsys_thaw_noirq(struct device *dev) +static int acpi_subsys_poweroff_noirq(struct device *dev) { - /* - * If the device is in runtime suspend, the "thaw" code may not work - * correctly with it, so skip the driver callback and make the PM core - * skip all of the subsequent "thaw" callbacks for the device. - */ - if (dev_pm_smart_suspend_and_suspended(dev)) { - dev_pm_skip_next_resume_phases(dev); + if (dev_pm_smart_suspend_and_suspended(dev)) return 0; - } - return pm_generic_thaw_noirq(dev); + return pm_generic_poweroff_noirq(dev); } -EXPORT_SYMBOL_GPL(acpi_subsys_thaw_noirq); #endif /* CONFIG_PM_SLEEP */ static struct dev_pm_domain acpi_general_pm_domain = { @@ -1186,14 +1247,10 @@ static struct dev_pm_domain acpi_general_pm_domain = { .resume_noirq = acpi_subsys_resume_noirq, .resume_early = acpi_subsys_resume_early, .freeze = acpi_subsys_freeze, - .freeze_late = acpi_subsys_freeze_late, - .freeze_noirq = acpi_subsys_freeze_noirq, - .thaw_noirq = acpi_subsys_thaw_noirq, - .poweroff = acpi_subsys_suspend, - .poweroff_late = acpi_subsys_suspend_late, - .poweroff_noirq = acpi_subsys_suspend_noirq, - .restore_noirq = acpi_subsys_resume_noirq, - .restore_early = acpi_subsys_resume_early, + .poweroff = acpi_subsys_poweroff, + .poweroff_late = acpi_subsys_poweroff_late, + .poweroff_noirq = acpi_subsys_poweroff_noirq, + .restore_early = acpi_subsys_restore_early, #endif }, }; |