19 files changed, 85 insertions, 64 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c
index 7e57447bf5f4..112e358f0f9b 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c
@@ -2667,19 +2667,21 @@ static void dce_v10_0_cursor_reset(struct drm_crtc *crtc)
         }
 }
 
-static void dce_v10_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-                                    u16 *blue, uint32_t start, uint32_t size)
+static int dce_v10_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
+                                    u16 *blue, uint32_t size)
 {
         struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-        int end = (start + size > 256) ? 256 : start + size, i;
+        int i;
 
         /* userspace palettes are always correct as is */
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 amdgpu_crtc->lut_r[i] = red[i] >> 6;
                 amdgpu_crtc->lut_g[i] = green[i] >> 6;
                 amdgpu_crtc->lut_b[i] = blue[i] >> 6;
         }
         dce_v10_0_crtc_load_lut(crtc);
+
+        return 0;
 }
 
 static void dce_v10_0_crtc_destroy(struct drm_crtc *crtc)
diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c
index da101551960b..b522fa2435a8 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c
@@ -2678,19 +2678,21 @@ static void dce_v11_0_cursor_reset(struct drm_crtc *crtc)
         }
 }
 
-static void dce_v11_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-                                    u16 *blue, uint32_t start, uint32_t size)
+static int dce_v11_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
+                                    u16 *blue, uint32_t size)
 {
         struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-        int end = (start + size > 256) ? 256 : start + size, i;
+        int i;
 
         /* userspace palettes are always correct as is */
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 amdgpu_crtc->lut_r[i] = red[i] >> 6;
                 amdgpu_crtc->lut_g[i] = green[i] >> 6;
                 amdgpu_crtc->lut_b[i] = blue[i] >> 6;
         }
         dce_v11_0_crtc_load_lut(crtc);
+
+        return 0;
 }
 
 static void dce_v11_0_crtc_destroy(struct drm_crtc *crtc)
diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c
index 41d9bc5f9c0e..b50ed72feedb 100644
--- a/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c
@@ -2574,19 +2574,21 @@ static void dce_v8_0_cursor_reset(struct drm_crtc *crtc)
         }
 }
 
-static void dce_v8_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-                                    u16 *blue, uint32_t start, uint32_t size)
+static int dce_v8_0_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
+                                   u16 *blue, uint32_t size)
 {
         struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc);
-        int end = (start + size > 256) ? 256 : start + size, i;
+        int i;
 
         /* userspace palettes are always correct as is */
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 amdgpu_crtc->lut_r[i] = red[i] >> 6;
                 amdgpu_crtc->lut_g[i] = green[i] >> 6;
                 amdgpu_crtc->lut_b[i] = blue[i] >> 6;
         }
         dce_v8_0_crtc_load_lut(crtc);
+
+        return 0;
 }
 
 static void dce_v8_0_crtc_destroy(struct drm_crtc *crtc)
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index c337922606e3..5957c3e659fe 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -624,19 +624,21 @@ static void ast_crtc_reset(struct drm_crtc *crtc)
 
 }
 
-static void ast_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-                                 u16 *blue, uint32_t start, uint32_t size)
+static int ast_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
+                              u16 *blue, uint32_t size)
 {
         struct ast_crtc *ast_crtc = to_ast_crtc(crtc);
-        int end = (start + size > 256) ? 256 : start + size, i;
+        int i;
 
         /* userspace palettes are always correct as is */
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 ast_crtc->lut_r[i] = red[i] >> 8;
                 ast_crtc->lut_g[i] = green[i] >> 8;
                 ast_crtc->lut_b[i] = blue[i] >> 8;
         }
         ast_crtc_load_lut(crtc);
+
+        return 0;
 }
 
 
diff --git a/drivers/gpu/drm/cirrus/cirrus_mode.c b/drivers/gpu/drm/cirrus/cirrus_mode.c
index 0b1a411cb89e..17c915d9a03e 100644
--- a/drivers/gpu/drm/cirrus/cirrus_mode.c
+++ b/drivers/gpu/drm/cirrus/cirrus_mode.c
@@ -325,18 +325,20 @@ static void cirrus_crtc_commit(struct drm_crtc *crtc)
  * use this for 8-bit mode so can't perform smooth fades on deeper modes,
  * but it's a requirement that we provide the function
  */
-static void cirrus_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-                                  u16 *blue, uint32_t start, uint32_t size)
+static int cirrus_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
+                                 u16 *blue, uint32_t size)
 {
         struct cirrus_crtc *cirrus_crtc = to_cirrus_crtc(crtc);
         int i;
 
-        for (i = 0; i < CIRRUS_LUT_SIZE; i++) {
+        for (i = 0; i < size; i++) {
                 cirrus_crtc->lut_r[i] = red[i];
                 cirrus_crtc->lut_g[i] = green[i];
                 cirrus_crtc->lut_b[i] = blue[i];
         }
         cirrus_crtc_load_lut(crtc);
+
+        return 0;
 }
 
 /* Simple cleanup function */
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 4342f3dfc0e1..191d84f12e67 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -2920,16 +2920,15 @@ EXPORT_SYMBOL(drm_atomic_helper_connector_destroy_state);
  * @red: red correction table
  * @green: green correction table
  * @blue: green correction table
- * @start: first entry, must always be 0
  * @size: size of the tables
  *
  * Implements support for legacy gamma correction table for drivers
  * that support color management through the DEGAMMA_LUT/GAMMA_LUT
  * properties.
  */
-void drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc,
-                                        u16 *red, u16 *green, u16 *blue,
-                                        uint32_t start, uint32_t size)
+int drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc,
+                                       u16 *red, u16 *green, u16 *blue,
+                                       uint32_t size)
 {
         struct drm_device *dev = crtc->dev;
         struct drm_mode_config *config = &dev->mode_config;
@@ -2941,7 +2940,7 @@ void drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc,
 
         state = drm_atomic_state_alloc(crtc->dev);
         if (!state)
-                return;
+                return -ENOMEM;
 
         blob = drm_property_create_blob(dev,
                                         sizeof(struct drm_color_lut) * size,
@@ -2992,7 +2991,7 @@ retry:
 
         drm_property_unreference_blob(blob);
 
-        return;
+        return 0;
 fail:
         if (ret == -EDEADLK)
                 goto backoff;
@@ -3000,7 +2999,7 @@ fail:
         drm_atomic_state_free(state);
         drm_property_unreference_blob(blob);
 
-        return;
+        return ret;
 backoff:
         drm_atomic_state_clear(state);
         drm_atomic_legacy_backoff(state);
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index ba6174fc117c..889e01f1b3f2 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -5172,7 +5172,7 @@ int drm_mode_gamma_set_ioctl(struct drm_device *dev,
                 goto out;
         }
 
-        crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);
+        ret = crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, crtc->gamma_size);
 
 out:
         drm_modeset_unlock_all(dev);
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 7590df5e2e72..58ed6e6d4f12 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -227,7 +227,7 @@ static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
         g_base = r_base + crtc->gamma_size;
         b_base = g_base + crtc->gamma_size;
 
-        crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);
+        crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, crtc->gamma_size);
 }
 
 /**
diff --git a/drivers/gpu/drm/gma500/gma_display.c b/drivers/gpu/drm/gma500/gma_display.c
index c95406e6f44d..5b636bf0b467 100644
--- a/drivers/gpu/drm/gma500/gma_display.c
+++ b/drivers/gpu/drm/gma500/gma_display.c
@@ -175,20 +175,21 @@ void gma_crtc_load_lut(struct drm_crtc *crtc)
         }
 }
 
-void gma_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green, u16 *blue,
-                        u32 start, u32 size)
+int gma_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green, u16 *blue,
+                       u32 size)
 {
         struct gma_crtc *gma_crtc = to_gma_crtc(crtc);
         int i;
-        int end = (start + size > 256) ? 256 : start + size;
 
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 gma_crtc->lut_r[i] = red[i] >> 8;
                 gma_crtc->lut_g[i] = green[i] >> 8;
                 gma_crtc->lut_b[i] = blue[i] >> 8;
         }
 
         gma_crtc_load_lut(crtc);
+
+        return 0;
 }
 
 /**
diff --git a/drivers/gpu/drm/gma500/gma_display.h b/drivers/gpu/drm/gma500/gma_display.h
index b2491c65f053..e72dd08b701b 100644
--- a/drivers/gpu/drm/gma500/gma_display.h
+++ b/drivers/gpu/drm/gma500/gma_display.h
@@ -72,8 +72,8 @@ extern int gma_crtc_cursor_set(struct drm_crtc *crtc,
                                uint32_t width, uint32_t height);
 extern int gma_crtc_cursor_move(struct drm_crtc *crtc, int x, int y);
 extern void gma_crtc_load_lut(struct drm_crtc *crtc);
-extern void gma_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-                               u16 *blue, u32 start, u32 size);
+extern int gma_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
+                              u16 *blue, u32 size);
 extern void gma_crtc_dpms(struct drm_crtc *crtc, int mode);
 extern void gma_crtc_prepare(struct drm_crtc *crtc);
 extern void gma_crtc_commit(struct drm_crtc *crtc);
diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 14e64e08909e..f6d5892d03f1 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -1344,19 +1344,20 @@ static void mga_crtc_commit(struct drm_crtc *crtc)
  * use this for 8-bit mode so can't perform smooth fades on deeper modes,
  * but it's a requirement that we provide the function
  */
-static void mga_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-                                  u16 *blue, uint32_t start, uint32_t size)
+static int mga_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
+                              u16 *blue, uint32_t size)
 {
         struct mga_crtc *mga_crtc = to_mga_crtc(crtc);
-        int end = (start + size > MGAG200_LUT_SIZE) ? MGAG200_LUT_SIZE : start + size;
         int i;
 
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 mga_crtc->lut_r[i] = red[i] >> 8;
                 mga_crtc->lut_g[i] = green[i] >> 8;
                 mga_crtc->lut_b[i] = blue[i] >> 8;
         }
         mga_crtc_load_lut(crtc);
+
+        return 0;
 }
 
 /* Simple cleanup function */
diff --git a/drivers/gpu/drm/nouveau/dispnv04/crtc.c b/drivers/gpu/drm/nouveau/dispnv04/crtc.c
index 6f318c54da33..0cb7a18cde26 100644
--- a/drivers/gpu/drm/nouveau/dispnv04/crtc.c
+++ b/drivers/gpu/drm/nouveau/dispnv04/crtc.c
@@ -785,14 +785,14 @@ nv_crtc_disable(struct drm_crtc *crtc)
         nouveau_bo_ref(NULL, &disp->image[nv_crtc->index]);
 }
 
-static void
-nv_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b, uint32_t start,
+static int
+nv_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
                   uint32_t size)
 {
-        int end = (start + size > 256) ? 256 : start + size, i;
         struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
+        int i;
 
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 nv_crtc->lut.r[i] = r[i];
                 nv_crtc->lut.g[i] = g[i];
                 nv_crtc->lut.b[i] = b[i];
@@ -805,10 +805,12 @@ nv_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b, uint32_t start,
          */
         if (!nv_crtc->base.primary->fb) {
                 nv_crtc->lut.depth = 0;
-                return;
+                return 0;
         }
 
         nv_crtc_gamma_load(crtc);
+
+        return 0;
 }
 
 static int
diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index 3ffc2b0057bf..7a7788212df7 100644
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -1346,21 +1346,22 @@ nv50_crtc_cursor_move(struct drm_crtc *crtc, int x, int y)
         return 0;
 }
 
-static void
+static int
 nv50_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
-                    uint32_t start, uint32_t size)
+                    uint32_t size)
 {
         struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
-        u32 end = min_t(u32, start + size, 256);
         u32 i;
 
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 nv_crtc->lut.r[i] = r[i];
                 nv_crtc->lut.g[i] = g[i];
                 nv_crtc->lut.b[i] = b[i];
         }
 
         nv50_crtc_lut_load(crtc);
+
+        return 0;
 }
 
 static void
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
index 2fb18f13395c..e85c7a2f565b 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -231,19 +231,21 @@ void radeon_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
         *blue = radeon_crtc->lut_b[regno] << 6;
 }
 
-static void radeon_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-                                  u16 *blue, uint32_t start, uint32_t size)
+static int radeon_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
+                                 u16 *blue, uint32_t size)
 {
         struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
-        int end = (start + size > 256) ? 256 : start + size, i;
+        int i;
 
         /* userspace palettes are always correct as is */
-        for (i = start; i < end; i++) {
+        for (i = 0; i < size; i++) {
                 radeon_crtc->lut_r[i] = red[i] >> 6;
                 radeon_crtc->lut_g[i] = green[i] >> 6;
                 radeon_crtc->lut_b[i] = blue[i] >> 6;
         }
         radeon_crtc_load_lut(crtc);
+
+        return 0;
 }
 
 static void radeon_crtc_destroy(struct drm_crtc *crtc)
@@ -688,6 +690,7 @@ radeon_crtc_set_config(struct drm_mode_set *set)
         pm_runtime_put_autosuspend(dev->dev);
         return ret;
 }
+
 static const struct drm_crtc_funcs radeon_crtc_funcs = {
         .cursor_set2 = radeon_crtc_cursor_set2,
         .cursor_move = radeon_crtc_cursor_move,
diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index ba2e373ec901..4c0f26a644a3 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -175,20 +175,22 @@ vc4_crtc_lut_load(struct drm_crtc *crtc)
                 HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_b[i]);
 }
 
-static void
+static int
 vc4_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
-                   uint32_t start, uint32_t size)
+                   uint32_t size)
 {
         struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
         u32 i;
 
-        for (i = start; i < start + size; i++) {
+        for (i = 0; i < size; i++) {
                 vc4_crtc->lut_r[i] = r[i] >> 8;
                 vc4_crtc->lut_g[i] = g[i] >> 8;
                 vc4_crtc->lut_b[i] = b[i] >> 8;
         }
 
         vc4_crtc_lut_load(crtc);
+
+        return 0;
 }
 
 static u32 vc4_get_fifo_full_level(u32 format)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 55231cce73a0..8a69d4da40b5 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -1404,9 +1404,9 @@ static int vmw_du_update_layout(struct vmw_private *dev_priv, unsigned num,
         return 0;
 }
 
-void vmw_du_crtc_gamma_set(struct drm_crtc *crtc,
-                           u16 *r, u16 *g, u16 *b,
-                           uint32_t start, uint32_t size)
+int vmw_du_crtc_gamma_set(struct drm_crtc *crtc,
+                          u16 *r, u16 *g, u16 *b,
+                          uint32_t size)
 {
         struct vmw_private *dev_priv = vmw_priv(crtc->dev);
         int i;
@@ -1418,6 +1418,8 @@ void vmw_du_crtc_gamma_set(struct drm_crtc *crtc,
                 vmw_write(dev_priv, SVGA_PALETTE_BASE + i * 3 + 1, g[i] >> 8);
                 vmw_write(dev_priv, SVGA_PALETTE_BASE + i * 3 + 2, b[i] >> 8);
         }
+
+        return 0;
 }
 
 int vmw_du_connector_dpms(struct drm_connector *connector, int mode)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.h b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.h
index 57203212c501..ff4803c107bc 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.h
@@ -195,9 +195,9 @@ struct vmw_display_unit {
 void vmw_du_cleanup(struct vmw_display_unit *du);
 void vmw_du_crtc_save(struct drm_crtc *crtc);
 void vmw_du_crtc_restore(struct drm_crtc *crtc);
-void vmw_du_crtc_gamma_set(struct drm_crtc *crtc,
+int vmw_du_crtc_gamma_set(struct drm_crtc *crtc,
                            u16 *r, u16 *g, u16 *b,
-                           uint32_t start, uint32_t size);
+                           uint32_t size);
 int vmw_du_crtc_cursor_set2(struct drm_crtc *crtc, struct drm_file *file_priv,
                             uint32_t handle, uint32_t width, uint32_t height,
                             int32_t hot_x, int32_t hot_y);
diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h
index b03bd83703b4..1877a7c18d8e 100644
--- a/include/drm/drm_atomic_helper.h
+++ b/include/drm/drm_atomic_helper.h
@@ -147,9 +147,9 @@ void
 __drm_atomic_helper_connector_destroy_state(struct drm_connector_state *state);
 void drm_atomic_helper_connector_destroy_state(struct drm_connector *connector,
                                           struct drm_connector_state *state);
-void drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc,
-                                        u16 *red, u16 *green, u16 *blue,
-                                        uint32_t start, uint32_t size);
+int drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc,
+                                       u16 *red, u16 *green, u16 *blue,
+                                       uint32_t size);
 
 /**
  * drm_atomic_crtc_for_each_plane - iterate over planes currently attached to CRTC
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index f59d8a2d8920..411be4f45506 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -479,8 +479,8 @@ struct drm_crtc_funcs {
          * going on, which should eventually be unified to just one set of
          * hooks.
          */
-        void (*gamma_set)(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
-                          uint32_t start, uint32_t size);
+        int (*gamma_set)(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
+                         uint32_t size);
 
         /**
          * @destroy: