drm/dsi: Add Turn On/Shutdown Peripheral command helpers

The MIPI_DSI_TURN_ON_PERIPHERAL and MIPI_DSI_SHUTDOWN_PERIPHERAL packets
are required for some panels, for example the Panasonic VVX10F034N00.
Signed-off-by: Werner Johansson <werner.johansson@sonymobile.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/drm_mipi_dsi.c

@@ -365,6 +365,44 @@ int mipi_dsi_create_packet(struct mipi_dsi_packet *packet,
 }
 EXPORT_SYMBOL(mipi_dsi_create_packet);
 
+/**
+ * mipi_dsi_shutdown_peripheral() - sends a Shutdown Peripheral command
+ * @dsi: DSI peripheral device
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int mipi_dsi_shutdown_peripheral(struct mipi_dsi_device *dsi)
+{
+	struct mipi_dsi_msg msg = {
+		.channel = dsi->channel,
+		.type = MIPI_DSI_SHUTDOWN_PERIPHERAL,
+		.tx_buf = (u8 [2]) { 0, 0 },
+		.tx_len = 2,
+	};
+
+	return mipi_dsi_device_transfer(dsi, &msg);
+}
+EXPORT_SYMBOL(mipi_dsi_shutdown_peripheral);
+
+/**
+ * mipi_dsi_turn_on_peripheral() - sends a Turn On Peripheral command
+ * @dsi: DSI peripheral device
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int mipi_dsi_turn_on_peripheral(struct mipi_dsi_device *dsi)
+{
+	struct mipi_dsi_msg msg = {
+		.channel = dsi->channel,
+		.type = MIPI_DSI_TURN_ON_PERIPHERAL,
+		.tx_buf = (u8 [2]) { 0, 0 },
+		.tx_len = 2,
+	};
+
+	return mipi_dsi_device_transfer(dsi, &msg);
+}
+EXPORT_SYMBOL(mipi_dsi_turn_on_peripheral);
+
 /*
  * mipi_dsi_set_maximum_return_packet_size() - specify the maximum size of the
  *    the payload in a long packet transmitted from the peripheral back to the

include/drm/drm_mipi_dsi.h

@@ -191,6 +191,8 @@ static inline int mipi_dsi_pixel_format_to_bpp(enum mipi_dsi_pixel_format fmt)
 struct mipi_dsi_device *of_find_mipi_dsi_device_by_node(struct device_node *np);
 int mipi_dsi_attach(struct mipi_dsi_device *dsi);
 int mipi_dsi_detach(struct mipi_dsi_device *dsi);
+int mipi_dsi_shutdown_peripheral(struct mipi_dsi_device *dsi);
+int mipi_dsi_turn_on_peripheral(struct mipi_dsi_device *dsi);
 int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
 					    u16 value);