From 77254950bb174d637cd88d1a74e137ecf3185a65 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 7 Aug 2012 13:50:14 +0200 Subject: PM: Make dev_pm_get_subsys_data() always return 0 on success MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commits 1d5fcfec22 (PM / Domains: Add device domain data reference counter) and 62d4490294 (PM / Domains: Allow device callbacks to be added at any time) added checks for the return value of dev_pm_get_subsys_data(), but those checks were incorrect, because that function returned 1 on success in some cases. Since all of the existing users of dev_pm_get_subsys_data() don't use the positive value returned by it on success, change its definition so that it always returns 0 when successful. Reported-by: Heiko Stübner Reported-by: Tushar Behera Signed-off-by: Rafael J. Wysocki --- drivers/base/power/clock_ops.c | 3 +-- drivers/base/power/common.c | 4 +--- 2 files changed, 2 insertions(+), 5 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index 869d7ff2227f..eb78e9640c4a 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -169,8 +169,7 @@ void pm_clk_init(struct device *dev) */ int pm_clk_create(struct device *dev) { - int ret = dev_pm_get_subsys_data(dev); - return ret < 0 ? ret : 0; + return dev_pm_get_subsys_data(dev); } /** diff --git a/drivers/base/power/common.c b/drivers/base/power/common.c index a14085cc613f..39c32529b833 100644 --- a/drivers/base/power/common.c +++ b/drivers/base/power/common.c @@ -24,7 +24,6 @@ int dev_pm_get_subsys_data(struct device *dev) { struct pm_subsys_data *psd; - int ret = 0; psd = kzalloc(sizeof(*psd), GFP_KERNEL); if (!psd) @@ -40,7 +39,6 @@ int dev_pm_get_subsys_data(struct device *dev) dev->power.subsys_data = psd; pm_clk_init(dev); psd = NULL; - ret = 1; } spin_unlock_irq(&dev->power.lock); @@ -48,7 +46,7 @@ int dev_pm_get_subsys_data(struct device *dev) /* kfree() verifies that its argument is nonzero. */ kfree(psd); - return ret; + return 0; } EXPORT_SYMBOL_GPL(dev_pm_get_subsys_data); -- cgit v1.2.3 From 7f321c26c04807834fef4c524d2b21573423fc74 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 15 Aug 2012 21:31:45 +0200 Subject: PM / Runtime: Fix rpm_resume() return value for power.no_callbacks set For devices whose power.no_callbacks flag is set, rpm_resume() should return 1 if the device's parent is already active, so that the callers of pm_runtime_get() don't think that they have to wait for the device to resume (asynchronously) in that case (the core won't queue up an asynchronous resume in that case, so there's nothing to wait for anyway). Modify the code accordingly (and make sure that an idle notification will be queued up on success, even if 1 is to be returned). Signed-off-by: Rafael J. Wysocki Acked-by: Alan Stern Cc: stable@vger.kernel.org --- drivers/base/power/runtime.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 59894873a3b3..9891a8559203 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -584,6 +584,7 @@ static int rpm_resume(struct device *dev, int rpmflags) || dev->parent->power.runtime_status == RPM_ACTIVE) { atomic_inc(&dev->parent->power.child_count); spin_unlock(&dev->parent->power.lock); + retval = 1; goto no_callback; /* Assume success. */ } spin_unlock(&dev->parent->power.lock); @@ -664,7 +665,7 @@ static int rpm_resume(struct device *dev, int rpmflags) } wake_up_all(&dev->power.wait_queue); - if (!retval) + if (retval >= 0) rpm_idle(dev, RPM_ASYNC); out: -- cgit v1.2.3 From 58a34de7b1a920d287d17d2ca08bc9aaf7e6d35b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 15 Aug 2012 21:31:55 +0200 Subject: PM / Runtime: Clear power.deferred_resume on success in rpm_suspend() The power.deferred_resume can only be set if the runtime PM status of device is RPM_SUSPENDING and it should be cleared after its status has been changed, regardless of whether or not the runtime suspend has been successful. However, it only is cleared on suspend failure, while it may remain set on successful suspend and is happily leaked to rpm_resume() executed in that case. That shouldn't happen, so if power.deferred_resume is set in rpm_suspend() after the status has been changed to RPM_SUSPENDED, clear it before calling rpm_resume(). Then, it doesn't need to be cleared before changing the status to RPM_SUSPENDING any more, because it's always cleared after the status has been changed to either RPM_SUSPENDED (on success) or RPM_ACTIVE (on failure). Signed-off-by: Rafael J. Wysocki Acked-by: Alan Stern Cc: stable@vger.kernel.org --- drivers/base/power/runtime.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 9891a8559203..b6e9d9b7982d 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -388,7 +388,6 @@ static int rpm_suspend(struct device *dev, int rpmflags) goto repeat; } - dev->power.deferred_resume = false; if (dev->power.no_callbacks) goto no_callback; /* Assume success. */ @@ -440,6 +439,7 @@ static int rpm_suspend(struct device *dev, int rpmflags) wake_up_all(&dev->power.wait_queue); if (dev->power.deferred_resume) { + dev->power.deferred_resume = false; rpm_resume(dev, 0); retval = -EAGAIN; goto out; -- cgit v1.2.3 From 55d7ec4520e86d735d178c15d7df33d507bd43c6 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 15 Aug 2012 21:32:04 +0200 Subject: PM / Runtime: Check device PM QoS setting before "no callbacks" check If __dev_pm_qos_read_value(dev) returns a negative value, rpm_suspend() should return -EPERM for dev even if its power.no_callbacks flag is set. For this to happen, the device's power.no_callbacks flag has to be checked after the PM QoS check, so move the PM QoS check to rpm_check_suspend_allowed() (this will make it cover idle notifications as well as runtime suspend too). Signed-off-by: Rafael J. Wysocki Acked-by: Alan Stern Cc: stable@vger.kernel.org --- drivers/base/power/runtime.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index b6e9d9b7982d..7d9c1cb1c39a 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -147,6 +147,8 @@ static int rpm_check_suspend_allowed(struct device *dev) || (dev->power.request_pending && dev->power.request == RPM_REQ_RESUME)) retval = -EAGAIN; + else if (__dev_pm_qos_read_value(dev) < 0) + retval = -EPERM; else if (dev->power.runtime_status == RPM_SUSPENDED) retval = 1; @@ -402,12 +404,6 @@ static int rpm_suspend(struct device *dev, int rpmflags) goto out; } - if (__dev_pm_qos_read_value(dev) < 0) { - /* Negative PM QoS constraint means "never suspend". */ - retval = -EPERM; - goto out; - } - __update_runtime_status(dev, RPM_SUSPENDING); if (dev->pm_domain) -- cgit v1.2.3