[PATCH] expand gamma_set

[James Simmons]

Expand the crtc_gamma_set function to accept a starting offset. The 
reason for this is to eventually use this function for setcolreg from 
drm_fb_helper.c. The fbdev colormap function can start at any offset in 
the color map.

Signed-by: James Simmons <jsimmons at infradead.org>

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 4c68f76..a06d1da 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -2541,7 +2541,7 @@ int drm_mode_gamma_set_ioctl(struct drm_device *dev,
 		goto out;
 	}
 
-	crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, crtc->gamma_size);
+	crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);
 
 out:
 	mutex_unlock(&dev->mode_config.mutex);
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index f879589..07a430c 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4096,15 +4096,12 @@ void intel_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
 }
 
 static void intel_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-				 u16 *blue, uint32_t size)
+				 u16 *blue, uint32_t start, uint32_t size)
 {
+	int end = (start + size > 256) ? 256 : start + size, i;
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
-	int i;
-
-	if (size != 256)
-		return;
 
-	for (i = 0; i < 256; i++) {
+	for (i = start; i < end; i++) {
 		intel_crtc->lut_r[i] = red[i] >> 8;
 		intel_crtc->lut_g[i] = green[i] >> 8;
 		intel_crtc->lut_b[i] = blue[i] >> 8;
diff --git a/drivers/gpu/drm/nouveau/nv04_crtc.c b/drivers/gpu/drm/nouveau/nv04_crtc.c
index 1c20c08..88bb4ce 100644
--- a/drivers/gpu/drm/nouveau/nv04_crtc.c
+++ b/drivers/gpu/drm/nouveau/nv04_crtc.c
@@ -739,15 +739,13 @@ nv_crtc_gamma_load(struct drm_crtc *crtc)
 }
 
 static void
-nv_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b, uint32_t size)
+nv_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b, uint32_t start,
+		  uint32_t size)
 {
+	int end = (start + size > 256) ? 256 : start + size, i;
 	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
-	int i;
-
-	if (size != 256)
-		return;
 
-	for (i = 0; i < 256; i++) {
+	for (i = start; i < end; i++) {
 		nv_crtc->lut.r[i] = r[i];
 		nv_crtc->lut.g[i] = g[i];
 		nv_crtc->lut.b[i] = b[i];
diff --git a/drivers/gpu/drm/nouveau/nv50_crtc.c b/drivers/gpu/drm/nouveau/nv50_crtc.c
index 5d11ea1..2f5f2f2 100644
--- a/drivers/gpu/drm/nouveau/nv50_crtc.c
+++ b/drivers/gpu/drm/nouveau/nv50_crtc.c
@@ -381,15 +381,12 @@ nv50_crtc_cursor_move(struct drm_crtc *crtc, int x, int y)
 
 static void
 nv50_crtc_gamma_set(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
-		    uint32_t size)
+		    uint32_t start, uint32_t size)
 {
+	int end = (start + size > 256) ? 256 : start + size, i;
 	struct nouveau_crtc *nv_crtc = nouveau_crtc(crtc);
-	int i;
-
-	if (size != 256)
-		return;
 
-	for (i = 0; i < 256; i++) {
+	for (i = start; i < end; i++) {
 		nv_crtc->lut.r[i] = r[i];
 		nv_crtc->lut.g[i] = g[i];
 		nv_crtc->lut.b[i] = b[i];
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
index 283beed..64e69fd 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -161,17 +161,13 @@ void radeon_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
 }
 
 static void radeon_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
-				  u16 *blue, uint32_t size)
+				  u16 *blue, uint32_t start, uint32_t size)
 {
 	struct radeon_crtc *radeon_crtc = to_radeon_crtc(crtc);
-	int i;
-
-	if (size != 256) {
-		return;
-	}
+	int end = (start + size > 256) ? 256 : start + size, i;
 
 	/* userspace palettes are always correct as is */
-	for (i = 0; i < 256; i++) {
+	for (i = start; i < end; 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;
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c b/drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c
index cfaf690..2ff5cf7 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c
@@ -79,7 +79,7 @@ static void vmw_ldu_crtc_restore(struct drm_crtc *crtc)
 
 static void vmw_ldu_crtc_gamma_set(struct drm_crtc *crtc,
 				   u16 *r, u16 *g, u16 *b,
-				   uint32_t size)
+				   uint32_t start, uint32_t size)
 {
 }
 
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 93a1a31..2f2c4b5 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -343,7 +343,7 @@ struct drm_crtc_funcs {
 
 	/* Set gamma on the CRTC */
 	void (*gamma_set)(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
-			  uint32_t size);
+			  uint32_t start, uint32_t size);
 	/* Object destroy routine */
 	void (*destroy)(struct drm_crtc *crtc);