diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index e0d46defed835e5670dc1665da9917f807ad0c07..3f45290a0c5d5ae8c38b79970a21deea6a61a0f1 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -61,7 +61,7 @@ struct line_buffer {
  * @out_pixel: destination address to write the pixel
  * @in_pixel: pixel to write
  */
-typedef void (*pixel_write_t)(u8 *out_pixel, struct pixel_argb_u16 *in_pixel);
+typedef void (*pixel_write_t)(u8 *out_pixel, const struct pixel_argb_u16 *in_pixel);
 
 struct vkms_writeback_job {
 	struct iosys_map data[DRM_FORMAT_MAX_PLANES];
@@ -76,7 +76,7 @@ struct vkms_writeback_job {
  * @in_pixel: pointer to the pixel to read
  * @out_pixel: pointer to write the converted pixel
  */
-typedef void (*pixel_read_t)(u8 *in_pixel, struct pixel_argb_u16 *out_pixel);
+typedef void (*pixel_read_t)(const u8 *in_pixel, struct pixel_argb_u16 *out_pixel);
 
 /**
  * struct vkms_plane_state - Driver specific plane state
diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c
index b9544e67cd4fad7fdd4707527a6ff8ea8f2c35be..06aef516252956eb43e111c0e169f21c1ab5b482 100644
--- a/drivers/gpu/drm/vkms/vkms_formats.c
+++ b/drivers/gpu/drm/vkms/vkms_formats.c
@@ -75,7 +75,7 @@ static int get_x_position(const struct vkms_frame_info *frame_info, int limit, i
  * They are used in the vkms_compose_row() function to handle multiple formats.
  */
 
-static void ARGB8888_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
+static void ARGB8888_to_argb_u16(const u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
 {
 	/*
 	 * The 257 is the "conversion ratio". This number is obtained by the
@@ -89,7 +89,7 @@ static void ARGB8888_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
 	out_pixel->b = (u16)in_pixel[0] * 257;
 }
 
-static void XRGB8888_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
+static void XRGB8888_to_argb_u16(const u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
 {
 	out_pixel->a = (u16)0xffff;
 	out_pixel->r = (u16)in_pixel[2] * 257;
@@ -97,7 +97,7 @@ static void XRGB8888_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
 	out_pixel->b = (u16)in_pixel[0] * 257;
 }
 
-static void ARGB16161616_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
+static void ARGB16161616_to_argb_u16(const u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
 {
 	__le16 *pixel = (__le16 *)in_pixel;
 
@@ -107,7 +107,7 @@ static void ARGB16161616_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pi
 	out_pixel->b = le16_to_cpu(pixel[0]);
 }
 
-static void XRGB16161616_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
+static void XRGB16161616_to_argb_u16(const u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
 {
 	__le16 *pixel = (__le16 *)in_pixel;
 
@@ -117,7 +117,7 @@ static void XRGB16161616_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pi
 	out_pixel->b = le16_to_cpu(pixel[0]);
 }
 
-static void RGB565_to_argb_u16(u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
+static void RGB565_to_argb_u16(const u8 *in_pixel, struct pixel_argb_u16 *out_pixel)
 {
 	__le16 *pixel = (__le16 *)in_pixel;
 
@@ -173,7 +173,7 @@ void vkms_compose_row(struct line_buffer *stage_buffer, struct vkms_plane_state
  * They are used in vkms_writeback_row() to convert and store a pixel from the src_buffer to
  * the writeback buffer.
  */
-static void argb_u16_to_ARGB8888(u8 *out_pixel, struct pixel_argb_u16 *in_pixel)
+static void argb_u16_to_ARGB8888(u8 *out_pixel, const struct pixel_argb_u16 *in_pixel)
 {
 	/*
 	 * This sequence below is important because the format's byte order is
@@ -191,7 +191,7 @@ static void argb_u16_to_ARGB8888(u8 *out_pixel, struct pixel_argb_u16 *in_pixel)
 	out_pixel[0] = DIV_ROUND_CLOSEST(in_pixel->b, 257);
 }
 
-static void argb_u16_to_XRGB8888(u8 *out_pixel, struct pixel_argb_u16 *in_pixel)
+static void argb_u16_to_XRGB8888(u8 *out_pixel, const struct pixel_argb_u16 *in_pixel)
 {
 	out_pixel[3] = 0xff;
 	out_pixel[2] = DIV_ROUND_CLOSEST(in_pixel->r, 257);
@@ -199,7 +199,7 @@ static void argb_u16_to_XRGB8888(u8 *out_pixel, struct pixel_argb_u16 *in_pixel)
 	out_pixel[0] = DIV_ROUND_CLOSEST(in_pixel->b, 257);
 }
 
-static void argb_u16_to_ARGB16161616(u8 *out_pixel, struct pixel_argb_u16 *in_pixel)
+static void argb_u16_to_ARGB16161616(u8 *out_pixel, const struct pixel_argb_u16 *in_pixel)
 {
 	__le16 *pixel = (__le16 *)out_pixel;
 
@@ -209,7 +209,7 @@ static void argb_u16_to_ARGB16161616(u8 *out_pixel, struct pixel_argb_u16 *in_pi
 	pixel[0] = cpu_to_le16(in_pixel->b);
 }
 
-static void argb_u16_to_XRGB16161616(u8 *out_pixel, struct pixel_argb_u16 *in_pixel)
+static void argb_u16_to_XRGB16161616(u8 *out_pixel, const struct pixel_argb_u16 *in_pixel)
 {
 	__le16 *pixel = (__le16 *)out_pixel;
 
@@ -219,7 +219,7 @@ static void argb_u16_to_XRGB16161616(u8 *out_pixel, struct pixel_argb_u16 *in_pi
 	pixel[0] = cpu_to_le16(in_pixel->b);
 }
 
-static void argb_u16_to_RGB565(u8 *out_pixel, struct pixel_argb_u16 *in_pixel)
+static void argb_u16_to_RGB565(u8 *out_pixel, const struct pixel_argb_u16 *in_pixel)
 {
 	__le16 *pixel = (__le16 *)out_pixel;
 
