[PATCH v2 3/5] ACPI: PM: Simplify and fix PM domain hibernation callbacks

Rafael J. Wysocki
2019-07-01T10:58:23Z

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

First, after a previous change causing all runtime-suspended devices
in the ACPI PM domain (and ACPI LPSS devices) to be resumed before
creating a snapshot image of memory during hibernation, it is not
necessary to worry about the case in which them might be left in
runtime-suspend any more, so get rid of the code related to that from
ACPI PM domain and ACPI LPSS hibernation callbacks.

Second, it is not correct to use pm_generic_resume_early() and
acpi_subsys_resume_noirq() in hibernation "restore" callbacks (which
currently happens in the ACPI PM domain and ACPI LPSS), so introduce
proper _restore_late and _restore_noirq callbacks for the ACPI PM
domain and ACPI LPSS.

Fixes: 05087360fd7a (ACPI / PM: Take SMART_SUSPEND driver flag into account)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

-> v2:
* Add a comment explaining the acpi_lpss_resume_noirq() behavior.
* Make the new LPSS "restore" callbacks follow that behavior.

---
drivers/acpi/acpi_lpss.c | 61 ++++++++++++++++++++++++++++++++++++++++-------
drivers/acpi/device_pm.c | 61 ++++++-----------------------------------------
include/linux/acpi.h | 10 -------
3 files changed, 61 insertions(+), 71 deletions(-)

Index: linux-pm/drivers/acpi/device_pm.c
===================================================================
--- linux-pm.orig/drivers/acpi/device_pm.c
+++ linux-pm/drivers/acpi/device_pm.c
@@ -1116,7 +1116,7 @@ EXPORT_SYMBOL_GPL(acpi_subsys_suspend_no
* 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;
@@ -1131,7 +1131,6 @@ int acpi_subsys_resume_noirq(struct devi

return pm_generic_resume_noirq(dev);
}
-EXPORT_SYMBOL_GPL(acpi_subsys_resume_noirq);

/**
* acpi_subsys_resume_early - Resume device using ACPI.
@@ -1141,12 +1140,11 @@ EXPORT_SYMBOL_GPL(acpi_subsys_resume_noi
* 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.
@@ -1169,52 +1167,15 @@ int acpi_subsys_freeze(struct device *de
EXPORT_SYMBOL_GPL(acpi_subsys_freeze);

/**
- * acpi_subsys_freeze_late - Run the device driver's "late" freeze callback.
- * @dev: Device to handle.
- */
-int acpi_subsys_freeze_late(struct device *dev)
-{
-
- if (dev_pm_smart_suspend_and_suspended(dev))
- return 0;
-
- return pm_generic_freeze_late(dev);
-}
-EXPORT_SYMBOL_GPL(acpi_subsys_freeze_late);
-
-/**
- * acpi_subsys_freeze_noirq - Run the device driver's "noirq" freeze callback.
- * @dev: Device to handle.
- */
-int acpi_subsys_freeze_noirq(struct device *dev)
-{
-
- if (dev_pm_smart_suspend_and_suspended(dev))
- return 0;
-
- return pm_generic_freeze_noirq(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_restore_early - Restore device using ACPI.
+ * @dev: Device to restore.
*/
-int acpi_subsys_thaw_noirq(struct device *dev)
+int acpi_subsys_restore_early(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);
- return 0;
- }
-
- return pm_generic_thaw_noirq(dev);
+ int ret = acpi_dev_resume(dev);
+ return ret ? ret : pm_generic_restore_early(dev);
}
-EXPORT_SYMBOL_GPL(acpi_subsys_thaw_noirq);
+EXPORT_SYMBOL_GPL(acpi_subsys_restore_early);
#endif /* CONFIG_PM_SLEEP */

static struct dev_pm_domain acpi_general_pm_domain = {
@@ -1230,14 +1191,10 @@ static struct dev_pm_domain acpi_general
.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,
+ .restore_early = acpi_subsys_restore_early,
#endif
},
};
Index: linux-pm/include/linux/acpi.h
===================================================================
--- linux-pm.orig/include/linux/acpi.h
+++ linux-pm/include/linux/acpi.h
@@ -918,26 +918,16 @@ int acpi_subsys_prepare(struct device *d
void acpi_subsys_complete(struct device *dev);
int acpi_subsys_suspend_late(struct device *dev);
int acpi_subsys_suspend_noirq(struct device *dev);
-int acpi_subsys_resume_noirq(struct device *dev);
-int acpi_subsys_resume_early(struct device *dev);
int acpi_subsys_suspend(struct device *dev);
int acpi_subsys_freeze(struct device *dev);
-int acpi_subsys_freeze_late(struct device *dev);
-int acpi_subsys_freeze_noirq(struct device *dev);
-int acpi_subsys_thaw_noirq(struct device *dev);
#else
static inline int acpi_dev_resume_early(struct device *dev) { return 0; }
static inline int acpi_subsys_prepare(struct device *dev) { return 0; }
static inline void acpi_subsys_complete(struct device *dev) {}
static inline int acpi_subsys_suspend_late(struct device *dev) { return 0; }
static inline int acpi_subsys_suspend_noirq(struct device *dev) { return 0; }
-static inline int acpi_subsys_resume_noirq(struct device *dev) { return 0; }
-static inline int acpi_subsys_resume_early(struct device *dev) { return 0; }
static inline int acpi_subsys_suspend(struct device *dev) { return 0; }
static inline int acpi_subsys_freeze(struct device *dev) { return 0; }
-static inline int acpi_subsys_freeze_late(struct device *dev) { return 0; }
-static inline int acpi_subsys_freeze_noirq(struct device *dev) { return 0; }
-static inline int acpi_subsys_thaw_noirq(struct device *dev) { return 0; }
#endif

#ifdef CONFIG_ACPI
Index: linux-pm/drivers/acpi/acpi_lpss.c
===================================================================
--- linux-pm.orig/drivers/acpi/acpi_lpss.c
+++ linux-pm/drivers/acpi/acpi_lpss.c
@@ -1091,16 +1091,62 @@ static int acpi_lpss_resume_noirq(struct
struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
int ret;

- ret = acpi_subsys_resume_noirq(dev);
+ /* Follow acpi_subsys_resume_noirq(). */
+ if (dev_pm_may_skip_resume(dev))
+ return 0;
+
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ pm_runtime_set_active(dev);
+
+ ret = pm_generic_resume_noirq(dev);
if (ret)
return ret;

- if (!dev_pm_may_skip_resume(dev) && pdata->dev_desc->resume_from_noirq)
- ret = acpi_lpss_do_resume_early(dev);
+ if (!pdata->dev_desc->resume_from_noirq)
+ return 0;
+
+ /*
+ * The driver's ->resume_early callback will be invoked by
+ * acpi_lpss_do_resume_early(), with the assumption that the driver
+ * really wanted to run that code in ->resume_noirq, but it could not
+ * run before acpi_dev_resume() and the driver expected the latter to be
+ * called in the "early" phase.
+ */
+ return acpi_lpss_do_resume_early(dev);
+}
+
+static int acpi_lpss_do_restore_early(struct device *dev)
+{
+ int ret = acpi_lpss_resume(dev);
+
+ return ret ? ret : pm_generic_restore_early(dev);
+}
+
+static int acpi_lpss_restore_early(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+
+ if (pdata->dev_desc->resume_from_noirq)
+ return 0;

- return ret;
+ return acpi_lpss_do_restore_early(dev);
}

+static int acpi_lpss_restore_noirq(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ ret = pm_generic_restore_noirq(dev);
+ if (ret)
+ return ret;
+
+ if (!pdata->dev_desc->resume_from_noirq)
+ return 0;
+
+ /* This is analogous to what happens in acpi_lpss_resume_noirq(). */
+ return acpi_lpss_do_restore_early(dev);
+}
#endif /* CONFIG_PM_SLEEP */

static int acpi_lpss_runtime_suspend(struct device *dev)
@@ -1134,14 +1180,11 @@ static struct dev_pm_domain acpi_lpss_pm
.resume_noirq = acpi_lpss_resume_noirq,
.resume_early = acpi_lpss_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_lpss_suspend_late,
.poweroff_noirq = acpi_lpss_suspend_noirq,
- .restore_noirq = acpi_lpss_resume_noirq,
- .restore_early = acpi_lpss_resume_early,
+ .restore_noirq = acpi_lpss_restore_noirq,
+ .restore_early = acpi_lpss_restore_early,
#endif
.runtime_suspend = acpi_lpss_runtime_suspend,
.runtime_resume = acpi_lpss_runtime_resume,