usb: gadget: udc-core: move sysfs_notify() to a workqueue
usb_gadget_set_state() will call sysfs_notify()
which might sleep. Some users might want to call
usb_gadget_set_state() from the very IRQ handler
which actually changes the gadget state.
Instead of having every UDC driver add their own
workqueue for such a simple notification, we're
adding it generically to our struct usb_gadget,
so the details are hidden from all UDC drivers.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/udc-core.c b/drivers/usb/gadget/udc-core.c
index c28ac98..3122ab9 100644
--- a/drivers/usb/gadget/udc-core.c
+++ b/drivers/usb/gadget/udc-core.c
@@ -23,6 +23,7 @@
#include <linux/list.h>
#include <linux/err.h>
#include <linux/dma-mapping.h>
+#include <linux/workqueue.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
@@ -105,11 +106,18 @@
/* ------------------------------------------------------------------------- */
+static void usb_gadget_state_work(struct work_struct *work)
+{
+ struct usb_gadget *gadget = work_to_gadget(work);
+
+ sysfs_notify(&gadget->dev.kobj, NULL, "status");
+}
+
void usb_gadget_set_state(struct usb_gadget *gadget,
enum usb_device_state state)
{
gadget->state = state;
- sysfs_notify(&gadget->dev.kobj, NULL, "status");
+ schedule_work(&gadget->work);
}
EXPORT_SYMBOL_GPL(usb_gadget_set_state);
@@ -196,6 +204,7 @@
goto err1;
dev_set_name(&gadget->dev, "gadget");
+ INIT_WORK(&gadget->work, usb_gadget_state_work);
gadget->dev.parent = parent;
#ifdef CONFIG_HAS_DMA
@@ -315,6 +324,7 @@
usb_gadget_remove_driver(udc);
kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
+ flush_work(&gadget->work);
device_unregister(&udc->dev);
device_unregister(&gadget->dev);
}