| Message ID | 1663294501-6377-1-git-send-email-u0084500@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
| Series | [RFC] PM: core: Add pm_wakeup_pending check in device suspend_noirq | expand |
On Fri, Sep 16, 2022 at 4:15 AM cy_huang <u0084500@gmail.com> wrote: > > From: ChiYuan Huang <cy_huang@richtek.com> > > In 'dpm_suspend_noirq', it will do the sychronized_irq to guarantee all > irqs are all done, and then do any wakeup flag set. > > For some peripherial deivces like as I2C/SPI, to speed up the irq handling, > it may use 'pm_stay_awake' and really handle in another thread context like > as workqueue. > > But in mem suspend flow, after 'dpm_suspend_noirq" stage, the next > 'pm_wakeup_pending' check will be at 'syscore_suspend'. > > The checkpoint seems too late and cause I2C/SPI fail during 'noirq' to > 'syscore_suspend' What exactly do you mean by "fail" here? >. But some adapter was already be marked as 'suspended' > at 'noirq' callback, any I2C/SPI xfer will return the error flag '-ESHUTDOWN'. > > After the code trace, it seems all device callback will do 'pm_wakeup_pending' > check, except 'noirq'. > > This patch is to add 'pm_wakeup_pending' check in 'noirq' sage to prevent this > kind of usage. > > Signed-off-by: ChiYuan Huang <cy_huang@richtek.com> > --- > Hi, > > Is there any rule to define when I2C/SPI host controller need to mark adapter as > 'suspended'? > > I trace 'drivers/i2c/buses'.It seems there's no common rule, Some are 'suspend', > others may did it at 'suspend_noirq'. > > --- > drivers/base/power/main.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c > index c501392..7cd7dc5 100644 > --- a/drivers/base/power/main.c > +++ b/drivers/base/power/main.c > @@ -1210,6 +1210,11 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a > if (async_error) > goto Complete; > > + if (pm_wakeup_pending()) { > + async_error = -EBUSY; > + goto Complete; > + } > + > if (dev->power.syscore || dev->power.direct_complete) > goto Complete; > > -- > 2.7.4 >
Rafael J. Wysocki <rafael@kernel.org> 於 2022年9月22日 週四 凌晨2:13寫道： > > On Fri, Sep 16, 2022 at 4:15 AM cy_huang <u0084500@gmail.com> wrote: > > > > From: ChiYuan Huang <cy_huang@richtek.com> > > > > In 'dpm_suspend_noirq', it will do the sychronized_irq to guarantee all > > irqs are all done, and then do any wakeup flag set. > > > > For some peripherial deivces like as I2C/SPI, to speed up the irq handling, > > it may use 'pm_stay_awake' and really handle in another thread context like > > as workqueue. > > > > But in mem suspend flow, after 'dpm_suspend_noirq" stage, the next > > 'pm_wakeup_pending' check will be at 'syscore_suspend'. > > > > The checkpoint seems too late and cause I2C/SPI fail during 'noirq' to > > 'syscore_suspend' > > What exactly do you mean by "fail" here? For the below case Once the adapter is marked as 'Suspend', any i2c_xfer or spi_xfer will directly return 'ESHUTDOWN". There's no real I/O transferred, only the direct returned error code. > > >. But some adapter was already be marked as 'suspended' > > at 'noirq' callback, any I2C/SPI xfer will return the error flag '-ESHUTDOWN'. > > > > After the code trace, it seems all device callback will do 'pm_wakeup_pending' > > check, except 'noirq'. > > > > This patch is to add 'pm_wakeup_pending' check in 'noirq' sage to prevent this > > kind of usage. > > > > Signed-off-by: ChiYuan Huang <cy_huang@richtek.com> > > --- > > Hi, > > > > Is there any rule to define when I2C/SPI host controller need to mark adapter as > > 'suspended'? > > > > I trace 'drivers/i2c/buses'.It seems there's no common rule, Some are 'suspend', > > others may did it at 'suspend_noirq'. > > > > --- > > drivers/base/power/main.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c > > index c501392..7cd7dc5 100644 > > --- a/drivers/base/power/main.c > > +++ b/drivers/base/power/main.c > > @@ -1210,6 +1210,11 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a > > if (async_error) > > goto Complete; > > > > + if (pm_wakeup_pending()) { > > + async_error = -EBUSY; > > + goto Complete; > > + } > > + > > if (dev->power.syscore || dev->power.direct_complete) > > goto Complete; > > > > -- > > 2.7.4 > >
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index c501392..7cd7dc5 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -1210,6 +1210,11 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a if (async_error) goto Complete; + if (pm_wakeup_pending()) { + async_error = -EBUSY; + goto Complete; + } + if (dev->power.syscore || dev->power.direct_complete) goto Complete;