drivers: mailbox: Write data to the controller without sending
In addition to the requests that have to be sent to the remote processor
through the mailbox controller, there may be data, that may need to be
sent to the controller, but not the remote processor, atleast right
away. Such data need not be buffered by the mailbox framework. Since
data is also not sent to the remote processor immediately,
acknowlegement will not be expected by the mailbox framework.
Change-Id: I6b6e81f593af0ed1cadde269624ebfa2a1591f5b
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 36029fb..6c7f6c4 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -281,6 +281,34 @@
}
EXPORT_SYMBOL_GPL(mbox_send_message);
+/**
+ * mbox_send_controller_data- For client to submit a message to be
+ * sent only to the controller.
+ * @chan: Mailbox channel assigned to this client.
+ * @mssg: Client specific message typecasted.
+ *
+ * For client to submit data to the controller. There is no ACK expected
+ * from the controller. This request is not buffered in the mailbox framework.
+ *
+ * Return: Non-negative integer for successful submission (non-blocking mode)
+ * or transmission over chan (blocking mode).
+ * Negative value denotes failure.
+ */
+int mbox_send_controller_data(struct mbox_chan *chan, void *mssg)
+{
+ unsigned long flags;
+ int err;
+
+ if (!chan || !chan->cl)
+ return -EINVAL;
+
+ spin_lock_irqsave(&chan->lock, flags);
+ err = chan->mbox->ops->send_controller_data(chan, mssg);
+ spin_unlock_irqrestore(&chan->lock, flags);
+
+ return err;
+}
+EXPORT_SYMBOL(mbox_send_controller_data);
bool mbox_controller_is_idle(struct mbox_chan *chan)
{
diff --git a/include/linux/mailbox_client.h b/include/linux/mailbox_client.h
index 3d14b48..78f01ea 100644
--- a/include/linux/mailbox_client.h
+++ b/include/linux/mailbox_client.h
@@ -44,6 +44,7 @@
const char *name);
struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index);
int mbox_send_message(struct mbox_chan *chan, void *mssg);
+int mbox_send_controller_data(struct mbox_chan *chan, void *mssg);
void mbox_client_txdone(struct mbox_chan *chan, int r); /* atomic */
bool mbox_client_peek_data(struct mbox_chan *chan); /* atomic */
void mbox_free_channel(struct mbox_chan *chan); /* may sleep */
diff --git a/include/linux/mailbox_controller.h b/include/linux/mailbox_controller.h
index 86d7cc2..40c523d 100644
--- a/include/linux/mailbox_controller.h
+++ b/include/linux/mailbox_controller.h
@@ -24,6 +24,12 @@
* transmission of data is reported by the controller via
* mbox_chan_txdone (if it has some TX ACK irq). It must not
* sleep.
+ * @send_controller_data:
+ * Send data for the controller driver. This could be data to
+ * configure the controller or data that may be cached in the
+ * controller and not transmitted immediately. There is no ACK
+ * for this request and the request is not buffered in the
+ * controller. Must not sleep.
* @startup: Called when a client requests the chan. The controller
* could ask clients for additional parameters of communication
* to be provided via client's chan_data. This call may
@@ -46,6 +52,7 @@
*/
struct mbox_chan_ops {
int (*send_data)(struct mbox_chan *chan, void *data);
+ int (*send_controller_data)(struct mbox_chan *chan, void *data);
int (*startup)(struct mbox_chan *chan);
void (*shutdown)(struct mbox_chan *chan);
bool (*last_tx_done)(struct mbox_chan *chan);