driver core: Add deferred_probe attribute to devices in sysfs

It is sometimes useful to know that a device is on the deferred probe
list rather than, say, not having a driver available.  Expose this
information to user-space.

Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ben Hutchings
2016-08-16 14:34:18 +01:00
committed by Greg Kroah-Hartman
parent baa8809f60
commit 6751667a29
4 changed files with 34 additions and 0 deletions

View File

@@ -53,6 +53,19 @@ static LIST_HEAD(deferred_probe_pending_list);
static LIST_HEAD(deferred_probe_active_list);
static atomic_t deferred_trigger_count = ATOMIC_INIT(0);
static ssize_t deferred_probe_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
bool value;
mutex_lock(&deferred_probe_mutex);
value = !list_empty(&dev->p->deferred_probe);
mutex_unlock(&deferred_probe_mutex);
return sprintf(buf, "%d\n", value);
}
DEVICE_ATTR_RO(deferred_probe);
/*
* In some cases, like suspend to RAM or hibernation, It might be reasonable
* to prohibit probing of devices as it could be unsafe.