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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-03-25 20:54:57 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-03-25 20:54:57 -0700
commit72099304eeb316c4b00df3ae83efe4375729bd78 (patch)
tree3d4a7dbe61ad9bbaeb767b1fb43e190901bcb70b /drivers/base
parentb7ce40cff0b9f6597f8318fd761accd92727f61f (diff)
Revert "sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()"
This reverts commit d1ba277e79889085a2faec3b68b91ce89c63f888. As reported by Stephen, this patch breaks linux-next as a ppc patch suddenly (after 2 years) started using this old api call. So revert it for now, it will go away in 3.15-rc2 when we can change the PPC call to the new api. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Tejun Heo <tj@kernel.org> Cc: Stewart Smith <stewart@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base')
-rw-r--r--drivers/base/core.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 20da3ad1696b..0dd65281cc65 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -614,6 +614,39 @@ void device_remove_bin_file(struct device *dev,
}
EXPORT_SYMBOL_GPL(device_remove_bin_file);
+/**
+ * device_schedule_callback_owner - helper to schedule a callback for a device
+ * @dev: device.
+ * @func: callback function to invoke later.
+ * @owner: module owning the callback routine
+ *
+ * Attribute methods must not unregister themselves or their parent device
+ * (which would amount to the same thing). Attempts to do so will deadlock,
+ * since unregistration is mutually exclusive with driver callbacks.
+ *
+ * Instead methods can call this routine, which will attempt to allocate
+ * and schedule a workqueue request to call back @func with @dev as its
+ * argument in the workqueue's process context. @dev will be pinned until
+ * @func returns.
+ *
+ * This routine is usually called via the inline device_schedule_callback(),
+ * which automatically sets @owner to THIS_MODULE.
+ *
+ * Returns 0 if the request was submitted, -ENOMEM if storage could not
+ * be allocated, -ENODEV if a reference to @owner isn't available.
+ *
+ * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
+ * underlying sysfs routine (since it is intended for use by attribute
+ * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
+ */
+int device_schedule_callback_owner(struct device *dev,
+ void (*func)(struct device *), struct module *owner)
+{
+ return sysfs_schedule_callback(&dev->kobj,
+ (void (*)(void *)) func, dev, owner);
+}
+EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
+
static void klist_children_get(struct klist_node *n)
{
struct device_private *p = to_device_private_parent(n);