@@ -1083,9 +1083,12 @@ int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
acpi_handle handle, acpi_ec_query_func func,
void *data)
{
- struct acpi_ec_query_handler *handler =
- kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
+ struct acpi_ec_query_handler *handler;
+
+ if (!handle && !func)
+ return -EINVAL;
+ handler = kzalloc(sizeof(*handler), GFP_KERNEL);
if (!handler)
return -ENOMEM;
@@ -1097,6 +1100,7 @@ int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
kref_init(&handler->kref);
list_add(&handler->node, &ec->list);
mutex_unlock(&ec->mutex);
+
return 0;
}
EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
@@ -1109,9 +1113,15 @@ static void acpi_ec_remove_query_handlers(struct acpi_ec *ec,
mutex_lock(&ec->mutex);
list_for_each_entry_safe(handler, tmp, &ec->list, node) {
- if (remove_all || query_bit == handler->query_bit) {
+ /* When remove_all is false, we only remove custom query handlers
+ * which have handler->func set. This is done to preserve query
+ * handlers discovered thru ACPI, as they should continue handling
+ * EC queries.
+ */
+ if (remove_all || (handler->func && handler->query_bit == query_bit)) {
list_del_init(&handler->node);
list_add(&handler->node, &free_list);
+
}
}
mutex_unlock(&ec->mutex);
According to the ACPI spec part 5.6.4.1.2, EC query handlers discovered thru ACPI should not be removed when a driver removes his custom query handler. On the Acer Travelmate 4002WLMi for example, such a query handler is used as a fallback to handle the EC SMBus alert when no driver is present. Change acpi_ec_remove_query_handlers() so that only custom query handlers are removed then remove_all is false. Query handlers discovered thru ACPI will still get removed when remove_all is true, which happens on device removal. Also add a simple check to ensure that acpi_ec_add_query_handler() is always called with either handle or func being set, since custom query handlers are detected based whether handlers->func is set or not. Tested on a Acer Travelmate 4002WLMi. Signed-off-by: Armin Wolf <W_Armin@gmx.de> --- drivers/acpi/ec.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) -- 2.30.2