linux-kernel - [PATCH] PM / Domains: Use subsystem runtime suspend/resume callbacks by default

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Mon, 21 May 2012 00:37:51 +0200
From:	"Rafael J. Wysocki" <rjw@...k.pl>
To:	Linux PM list <linux-pm@...r.kernel.org>
Cc:	LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH] PM / Domains: Use subsystem runtime suspend/resume callbacks by default

From: Rafael J. Wysocki <rjw@...k.pl>

Currently, the default "save state" and "restore state" routines
for generic PM domains, pm_genpd_default_save_state() and
pm_genpd_default_restore_state(), respectively, only use runtime PM
callbacks provided by device drivers, but in general those callbacks
need not provide the entire necessary functionality.  Namely, in
general it may be necessary to execute subsystem (i.e. device type,
device class or bus type) callbacks that will carry out all of the
necessary operations.

For this reason, modify pm_genpd_default_save_state() and
pm_genpd_default_restore_state() to execute subsystem callbacks,
if they are provided, and fall back to driver callbacks otherwise.

Signed-off-by: Rafael J. Wysocki <rjw@...k.pl>
---
 drivers/base/power/domain.c |   32 ++++++++++++++++++++++++--------
 1 file changed, 24 insertions(+), 8 deletions(-)

Index: linux/drivers/base/power/domain.c
===================================================================
--- linux.orig/drivers/base/power/domain.c
+++ linux/drivers/base/power/domain.c
@@ -1738,16 +1738,24 @@ int genpd_detach_cpuidle(struct generic_
 static int pm_genpd_default_save_state(struct device *dev)
 {
 	int (*cb)(struct device *__dev);
-	struct device_driver *drv = dev->driver;
 
 	cb = dev_gpd_data(dev)->ops.save_state;
 	if (cb)
 		return cb(dev);
 
-	if (drv && drv->pm && drv->pm->runtime_suspend)
-		return drv->pm->runtime_suspend(dev);
+	if (dev->type && dev->type->pm)
+		cb = dev->type->pm->runtime_suspend;
+	else if (dev->class && dev->class->pm)
+		cb = dev->class->pm->runtime_suspend;
+	else if (dev->bus && dev->bus->pm)
+		cb = dev->bus->pm->runtime_suspend;
+	else
+		cb = NULL;
 
-	return 0;
+	if (!cb && dev->driver && dev->driver->pm)
+		cb = dev->driver->pm->runtime_suspend;
+
+	return cb ? cb(dev) : 0;
 }
 
 /**
@@ -1757,16 +1765,24 @@ static int pm_genpd_default_save_state(s
 static int pm_genpd_default_restore_state(struct device *dev)
 {
 	int (*cb)(struct device *__dev);
-	struct device_driver *drv = dev->driver;
 
 	cb = dev_gpd_data(dev)->ops.restore_state;
 	if (cb)
 		return cb(dev);
 
-	if (drv && drv->pm && drv->pm->runtime_resume)
-		return drv->pm->runtime_resume(dev);
+	if (dev->type && dev->type->pm)
+		cb = dev->type->pm->runtime_resume;
+	else if (dev->class && dev->class->pm)
+		cb = dev->class->pm->runtime_resume;
+	else if (dev->bus && dev->bus->pm)
+		cb = dev->bus->pm->runtime_resume;
+	else
+		cb = NULL;
+
+	if (!cb && dev->driver && dev->driver->pm)
+		cb = dev->driver->pm->runtime_resume;
 
-	return 0;
+	return cb ? cb(dev) : 0;
 }
 
 #ifdef CONFIG_PM_SLEEP
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/