On Wednesday, 20 of February 2008, Alan Stern wrote:
> On Wed, 20 Feb 2008, Pierre Ossman wrote:
>
> > > And why not simply fail the suspend if the resume routine doesn't exist
> > > and the suspend routine does? Maybe with an error message in the
> > > system log.
> >
> > For the asymmetric case, I guess that would do. But I still want to remove
> > devices when the bus handler has no suspend handling.
>
> Then it appears the correct approach is to use the new
> device_pm_schedule_removal() routine. It schedules the removal of a
> suspended device for a time when the system suspend is over.
Well, below is an uncompiled and untested but illustrating the idea that
might allow people not to bother with device_pm_schedule_removal()
explicitly and can fix the issue at hand.
[There are some cases that need handling and are not covered here.]
Please have a look.
Thanks,
Rafael
---
drivers/base/core.c | 5 ++++-
drivers/base/power/main.c | 22 ++++++++++++++++++++++
drivers/base/power/power.h | 5 +++++
3 files changed, 31 insertions(+), 1 deletion(-)
Index: linux-2.6/drivers/base/power/main.c
===================================================================
--- linux-2.6.orig/drivers/base/power/main.c
+++ linux-2.6/drivers/base/power/main.c
@@ -59,6 +59,26 @@ static DECLARE_RWSEM(pm_sleep_rwsem);
int (*platform_enable_wakeup)(struct device *dev, int is_on);
+static struct task_struct *suspending_task;
+static DEFINE_MUTEX(suspending_task_mtx);
+
+bool in_suspend_context(void)
+{
+ bool result;
+
+ mutex_lock(&suspending_task_mtx);
+ result = (suspending_task == current);
+ mutex_unlock(&suspending_task_mtx);
+ return result;
+}
+
+static void set_suspending_task(struct task_struct *task)
+{
+ mutex_lock(&suspending_task_mtx);
+ suspending_task = task;
+ mutex_unlock(&suspending_task_mtx);
+}
+
/**
* device_pm_add - add a device to the list of active devices
* @dev: Device to be added to the list
@@ -272,6 +292,7 @@ static void dpm_resume(void)
mutex_lock(&dpm_list_mtx);
}
mutex_unlock(&dpm_list_mtx);
+ set_suspending_task(NULL);
}
/**
@@ -460,6 +481,7 @@ static int dpm_suspend(pm_message_t stat
{
int error = 0;
+ set_suspending_task(current);
mutex_lock(&dpm_list_mtx);
while (!list_empty(&dpm_locked)) {
struct list_head *entry = dpm_locked.prev;
Index: linux-2.6/drivers/base/core.c
===================================================================
--- linux-2.6.orig/drivers/base/core.c
+++ linux-2.6/drivers/base/core.c
@@ -1162,7 +1162,10 @@ void device_destroy(struct class *class,
dev = class_find_device(class, &devt, __match_devt);
if (dev) {
put_device(dev);
- device_unregister(dev);
+ if (in_suspend_context())
+ device_pm_schedule_removal(dev);
+ else
+ device_unregister(dev);
}
}
EXPORT_SYMBOL_GPL(device_destroy);
Index: linux-2.6/drivers/base/power/power.h
===================================================================
--- linux-2.6.orig/drivers/base/power/power.h
+++ linux-2.6/drivers/base/power/power.h
@@ -11,6 +11,7 @@ static inline struct device *to_device(s
return container_of(entry, struct device, power.entry);
}
+extern bool in_suspend_context(void);
extern void device_pm_add(struct device *);
extern void device_pm_remove(struct device *);
extern int pm_sleep_lock(void);
@@ -18,6 +19,10 @@ extern void pm_sleep_unlock(void);
#else /* CONFIG_PM_SLEEP */
+static inline bool in_suspend_context(void)
+{
+ return false;
+}
static inline void device_pm_add(struct device *dev)
{
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
