drm: expand gamma_set

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@infradead.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

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);

drivers/gpu/drm/i915/intel_display.c

@@ -4330,15 +4330,12 @@ 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;

drivers/gpu/drm/nouveau/nv04_crtc.c

@@ -742,15 +742,13 @@ 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];

drivers/gpu/drm/nouveau/nv50_crtc.c

@@ -398,15 +398,12 @@ 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];

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;

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)
 {
 }
 

include/drm/drm_crtc.h

@@ -310,7 +310,7 @@ 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);