[Public]
> > +int acpi_register_lps0_callbacks(struct lps0_callback_handler *arg)
> > +{
> > + struct lps0_callback_handler *handler;
> > +
> > + if (!lps0_device_handle || sleep_no_lps0)
> > + return -ENODEV;
> > +
> > + handler = kmalloc(sizeof(*handler), GFP_KERNEL);
> > + if (!handler)
> > + return -ENOMEM;
> > + handler->prepare_late_callback = arg->prepare_late_callback;
> > + handler->restore_early_callback = arg->restore_early_callback;
> > + handler->context = arg->context;
> > +
> > + mutex_lock(&lps0_callback_handler_mutex);
> > + list_add(&handler->list_node, &lps0_callback_handler_head);
> > + mutex_unlock(&lps0_callback_handler_mutex);
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(acpi_register_lps0_callbacks);
>
> Typically with calls like these we simply let the caller own the struct
> lps0_callback_handler
> and only make the list_add() call here. Typically the struct
> lps0_callback_handler will
> be embedded in the driver_data of the driver registering the handler and it
> will
> call the unregister function before free-ing its driver_data.
>
When I put this together I was modeling it off of `struct acpi_wakeup_handler`
which the handling and the use in the kernel doesn't seem to follow the design pattern
you describe.
Rafael - can you please confirm which direction you want to see here for this?
> > +
> > +void acpi_unregister_lps0_callbacks(struct lps0_callback_handler *arg)
> > +{
> > + struct lps0_callback_handler *handler;
> > +
> > + mutex_lock(&lps0_callback_handler_mutex);
> > + list_for_each_entry(handler, &lps0_callback_handler_head,
> list_node) {
> > + if (handler->prepare_late_callback == arg-
> >prepare_late_callback &&
> > + handler->restore_early_callback == arg-
> >restore_early_callback &&
> > + handler->context == arg->context) {
> > + list_del(&handler->list_node);
> > + kfree(handler);
> > + break;
> > + }
> > + }
> > + mutex_unlock(&lps0_callback_handler_mutex);
> > +}
> > +EXPORT_SYMBOL_GPL(acpi_unregister_lps0_callbacks);
>
> And this then becomes just lock, list_del, unlock.
>
> Regards,
>
> Hans
