drm/mipi-dsi: add mipi_dsi_compression_mode_ext()

Add the extended version of mipi_dsi_compression_mode(). It provides
a way to specify the algorithm and PPS selector.

Reviewed-by: Marijn Suijten <[e-mail]>
Signed-off-by: Dmitry Baryshkov <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/drm_mipi_dsi.c

···
 EXPORT_SYMBOL(mipi_dsi_set_maximum_return_packet_size);
 
 /**
+ * mipi_dsi_compression_mode_ext() - enable/disable DSC on the peripheral
+ * @dsi: DSI peripheral device
+ * @enable: Whether to enable or disable the DSC
+ * @algo: Selected compression algorithm
+ * @pps_selector: Select PPS from the table of pre-stored or uploaded PPS entries
+ *
+ * Enable or disable Display Stream Compression on the peripheral.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int mipi_dsi_compression_mode_ext(struct mipi_dsi_device *dsi, bool enable,
+				  enum mipi_dsi_compression_algo algo,
+				  unsigned int pps_selector)
+{
+	u8 tx[2] = { };
+	struct mipi_dsi_msg msg = {
+		.channel = dsi->channel,
+		.type = MIPI_DSI_COMPRESSION_MODE,
+		.tx_len = sizeof(tx),
+		.tx_buf = tx,
+	};
+	int ret;
+
+	if (algo > 3 || pps_selector > 3)
+		return -EINVAL;
+
+	tx[0] = (enable << 0) |
+		(algo << 1) |
+		(pps_selector << 4);
+
+	ret = mipi_dsi_device_transfer(dsi, &msg);
+
+	return (ret < 0) ? ret : 0;
+}
+EXPORT_SYMBOL(mipi_dsi_compression_mode_ext);
+
+/**
  * mipi_dsi_compression_mode() - enable/disable DSC on the peripheral
  * @dsi: DSI peripheral device
  * @enable: Whether to enable or disable the DSC
···
  */
 int mipi_dsi_compression_mode(struct mipi_dsi_device *dsi, bool enable)
 {
-	/* Note: Needs updating for non-default PPS or algorithm */
-	u8 tx[2] = { enable << 0, 0 };
-	struct mipi_dsi_msg msg = {
-		.channel = dsi->channel,
-		.type = MIPI_DSI_COMPRESSION_MODE,
-		.tx_len = sizeof(tx),
-		.tx_buf = tx,
-	};
-	int ret = mipi_dsi_device_transfer(dsi, &msg);
-
-	return (ret < 0) ? ret : 0;
+	return mipi_dsi_compression_mode_ext(dsi, enable, MIPI_DSI_COMPRESSION_DSC, 0);
 }
 EXPORT_SYMBOL(mipi_dsi_compression_mode);
 

include/drm/drm_mipi_dsi.h

···
 	return -EINVAL;
 }
 
+enum mipi_dsi_compression_algo {
+	MIPI_DSI_COMPRESSION_DSC = 0,
+	MIPI_DSI_COMPRESSION_VENDOR = 3,
+	/* other two values are reserved, DSI 1.3 */
+};
+
 struct mipi_dsi_device *
 mipi_dsi_device_register_full(struct mipi_dsi_host *host,
 			      const struct mipi_dsi_device_info *info);
···
 int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
 					    u16 value);
 int mipi_dsi_compression_mode(struct mipi_dsi_device *dsi, bool enable);
+int mipi_dsi_compression_mode_ext(struct mipi_dsi_device *dsi, bool enable,
+				  enum mipi_dsi_compression_algo algo,
+				  unsigned int pps_selector);
 int mipi_dsi_picture_parameter_set(struct mipi_dsi_device *dsi,
 				   const struct drm_dsc_picture_parameter_set *pps);