drm/dsi: Introduce packet format helpers

Add two helpers, mipi_dsi_packet_format_is_{short,long}(), that help in
determining the format of a packet.

Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
index eb6dfe52cab2..adf056677498 100644
--- a/drivers/gpu/drm/drm_mipi_dsi.c
+++ b/drivers/gpu/drm/drm_mipi_dsi.c
@@ -199,6 +199,73 @@ int mipi_dsi_detach(struct mipi_dsi_device *dsi)
 EXPORT_SYMBOL(mipi_dsi_detach);
 
 /**
+ * mipi_dsi_packet_format_is_short - check if a packet is of the short format
+ * @type: MIPI DSI data type of the packet
+ *
+ * Return: true if the packet for the given data type is a short packet, false
+ * otherwise.
+ */
+bool mipi_dsi_packet_format_is_short(u8 type)
+{
+        switch (type) {
+        case MIPI_DSI_V_SYNC_START:
+        case MIPI_DSI_V_SYNC_END:
+        case MIPI_DSI_H_SYNC_START:
+        case MIPI_DSI_H_SYNC_END:
+        case MIPI_DSI_END_OF_TRANSMISSION:
+        case MIPI_DSI_COLOR_MODE_OFF:
+        case MIPI_DSI_COLOR_MODE_ON:
+        case MIPI_DSI_SHUTDOWN_PERIPHERAL:
+        case MIPI_DSI_TURN_ON_PERIPHERAL:
+        case MIPI_DSI_GENERIC_SHORT_WRITE_0_PARAM:
+        case MIPI_DSI_GENERIC_SHORT_WRITE_1_PARAM:
+        case MIPI_DSI_GENERIC_SHORT_WRITE_2_PARAM:
+        case MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM:
+        case MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM:
+        case MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM:
+        case MIPI_DSI_DCS_SHORT_WRITE:
+        case MIPI_DSI_DCS_SHORT_WRITE_PARAM:
+        case MIPI_DSI_DCS_READ:
+        case MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE:
+                return true;
+        }
+
+        return false;
+}
+EXPORT_SYMBOL(mipi_dsi_packet_format_is_short);
+
+/**
+ * mipi_dsi_packet_format_is_long - check if a packet is of the long format
+ * @type: MIPI DSI data type of the packet
+ *
+ * Return: true if the packet for the given data type is a long packet, false
+ * otherwise.
+ */
+bool mipi_dsi_packet_format_is_long(u8 type)
+{
+        switch (type) {
+        case MIPI_DSI_NULL_PACKET:
+        case MIPI_DSI_BLANKING_PACKET:
+        case MIPI_DSI_GENERIC_LONG_WRITE:
+        case MIPI_DSI_DCS_LONG_WRITE:
+        case MIPI_DSI_LOOSELY_PACKED_PIXEL_STREAM_YCBCR20:
+        case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR24:
+        case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR16:
+        case MIPI_DSI_PACKED_PIXEL_STREAM_30:
+        case MIPI_DSI_PACKED_PIXEL_STREAM_36:
+        case MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR12:
+        case MIPI_DSI_PACKED_PIXEL_STREAM_16:
+        case MIPI_DSI_PACKED_PIXEL_STREAM_18:
+        case MIPI_DSI_PIXEL_STREAM_3BYTE_18:
+        case MIPI_DSI_PACKED_PIXEL_STREAM_24:
+                return true;
+        }
+
+        return false;
+}
+EXPORT_SYMBOL(mipi_dsi_packet_format_is_long);
+
+/**
  * mipi_dsi_dcs_write - send DCS write command
  * @dsi: DSI device
  * @data: pointer to the command followed by parameters