+struct ec_cmd_desc {
+ u8 cmd;
+ u8 *inbuf, *outbuf;
+ size_t inlen, outlen;
+
+ int err;
+ struct completion finished;
+ struct list_head node;
+
+ void *priv;
+};
+
+static void olpc_ec_worker(struct work_struct *w);
+
+static DECLARE_WORK(ec_worker, olpc_ec_worker);
+static LIST_HEAD(ec_cmd_q);
+static DEFINE_SPINLOCK(ec_cmd_q_lock);
+
+static struct olpc_ec_driver *ec_driver;
+static void *ec_cb_arg;
+static DEFINE_MUTEX(ec_cb_lock);
+
+void olpc_ec_driver_register(struct olpc_ec_driver *drv, void *arg)
+{
+ ec_driver = drv;
+ ec_cb_arg = arg;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_driver_register);
+
+static void olpc_ec_worker(struct work_struct *w)
+{
+ struct ec_cmd_desc *desc = NULL;
+ unsigned long flags;
+
+ /* Grab the first pending command from the queue */
+ spin_lock_irqsave(&ec_cmd_q_lock, flags);
+ if (!list_empty(&ec_cmd_q)) {
+ desc = list_first_entry(&ec_cmd_q, struct ec_cmd_desc, node);
+ list_del(&desc->node);
+ }
+ spin_unlock_irqrestore(&ec_cmd_q_lock, flags);
+
+ /* Do we actually have anything to do? */
+ if (!desc)
+ return;
+
+ /* Protect the EC hw with a mutex; only run one cmd at a time */
+ mutex_lock(&ec_cb_lock);
+ desc->err = ec_driver->ec_cmd(desc->cmd, desc->inbuf, desc->inlen,
+ desc->outbuf, desc->outlen, ec_cb_arg);
+ mutex_unlock(&ec_cb_lock);
+
+ /* Finished, wake up olpc_ec_cmd() */
+ complete(&desc->finished);
+
+ /* Run the worker thread again in case there are more cmds pending */
+ schedule_work(&ec_worker);
+}
+
+/*
+ * Throw a cmd descripter onto the list. We now have SMP OLPC machines, so
+ * locking is pretty critical.
+ */
+static void queue_ec_descriptor(struct ec_cmd_desc *desc)
+{
+ unsigned long flags;
+
+ INIT_LIST_HEAD(&desc->node);
+
+ spin_lock_irqsave(&ec_cmd_q_lock, flags);
+ list_add_tail(&desc->node, &ec_cmd_q);
+ spin_unlock_irqrestore(&ec_cmd_q_lock, flags);
+
+ schedule_work(&ec_worker);
+}
+