drm/omap: constify write buffers

The write buffers are not modified, so they can be constant.
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201215104657.802264-5-tomi.valkeinen@ti.com

drivers/gpu/drm/omapdrm/dss/dsi.c

@@ -2603,11 +2603,11 @@ static inline void dsi_vc_write_long_payload(struct dsi_data *dsi, int channel,
 }
 
 static int dsi_vc_send_long(struct dsi_data *dsi, int channel, u8 data_type,
-			    u8 *data, u16 len, u8 ecc)
+			    const u8 *data, u16 len, u8 ecc)
 {
 	/*u32 val; */
 	int i;
-	u8 *p;
+	const u8 *p;
 	int r = 0;
 	u8 b1, b2, b3, b4;
 
@@ -2700,7 +2700,7 @@ static int dsi_vc_send_null(struct dsi_data *dsi, int channel)
 }
 
 static int dsi_vc_write_nosync_common(struct dsi_data *dsi, int channel,
-				      u8 *data, int len,
+				      const u8 *data, int len,
 				      enum dss_dsi_content_type type)
 {
 	int r;
@@ -2731,7 +2731,7 @@ static int dsi_vc_write_nosync_common(struct dsi_data *dsi, int channel,
 }
 
 static int dsi_vc_dcs_write_nosync(struct omap_dss_device *dssdev, int channel,
-		u8 *data, int len)
+		const u8 *data, int len)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 
@@ -2740,7 +2740,7 @@ static int dsi_vc_dcs_write_nosync(struct omap_dss_device *dssdev, int channel,
 }
 
 static int dsi_vc_generic_write_nosync(struct omap_dss_device *dssdev, int channel,
-		u8 *data, int len)
+		const u8 *data, int len)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 
@@ -2749,7 +2749,7 @@ static int dsi_vc_generic_write_nosync(struct omap_dss_device *dssdev, int chann
 }
 
 static int dsi_vc_write_common(struct omap_dss_device *dssdev,
-			       int channel, u8 *data, int len,
+			       int channel, const u8 *data, int len,
 			       enum dss_dsi_content_type type)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
@@ -2778,15 +2778,15 @@ static int dsi_vc_write_common(struct omap_dss_device *dssdev,
 	return r;
 }
 
-static int dsi_vc_dcs_write(struct omap_dss_device *dssdev, int channel, u8 *data,
-		int len)
+static int dsi_vc_dcs_write(struct omap_dss_device *dssdev, int channel,
+		const u8 *data, int len)
 {
 	return dsi_vc_write_common(dssdev, channel, data, len,
 			DSS_DSI_CONTENT_DCS);
 }
 
-static int dsi_vc_generic_write(struct omap_dss_device *dssdev, int channel, u8 *data,
-		int len)
+static int dsi_vc_generic_write(struct omap_dss_device *dssdev, int channel,
+		const u8 *data, int len)
 {
 	return dsi_vc_write_common(dssdev, channel, data, len,
 			DSS_DSI_CONTENT_GENERIC);
@@ -2812,7 +2812,7 @@ static int dsi_vc_dcs_send_read_request(struct dsi_data *dsi, int channel,
 }
 
 static int dsi_vc_generic_send_read_request(struct dsi_data *dsi, int channel,
-					    u8 *reqdata, int reqlen)
+					    const u8 *reqdata, int reqlen)
 {
 	u16 data;
 	u8 data_type;
@@ -2985,7 +2985,7 @@ static int dsi_vc_dcs_read(struct omap_dss_device *dssdev, int channel, u8 dcs_c
 }
 
 static int dsi_vc_generic_read(struct omap_dss_device *dssdev, int channel,
-		u8 *reqdata, int reqlen, u8 *buf, int buflen)
+		const u8 *reqdata, int reqlen, u8 *buf, int buflen)
 {
 	struct dsi_data *dsi = to_dsi_data(dssdev);
 	int r;

drivers/gpu/drm/omapdrm/dss/omapdss.h

@@ -312,18 +312,18 @@ struct omapdss_dsi_ops {
 
 	/* data transfer */
 	int (*dcs_write)(struct omap_dss_device *dssdev, int channel,
-			u8 *data, int len);
+			const u8 *data, int len);
 	int (*dcs_write_nosync)(struct omap_dss_device *dssdev, int channel,
-			u8 *data, int len);
+			const u8 *data, int len);
 	int (*dcs_read)(struct omap_dss_device *dssdev, int channel, u8 dcs_cmd,
 			u8 *data, int len);
 
 	int (*gen_write)(struct omap_dss_device *dssdev, int channel,
-			u8 *data, int len);
+			const u8 *data, int len);
 	int (*gen_write_nosync)(struct omap_dss_device *dssdev, int channel,
-			u8 *data, int len);
+			const u8 *data, int len);
 	int (*gen_read)(struct omap_dss_device *dssdev, int channel,
-			u8 *reqdata, int reqlen,
+			const u8 *reqdata, int reqlen,
 			u8 *data, int len);
 
 	int (*bta_sync)(struct omap_dss_device *dssdev, int channel);