1 files changed, 54 insertions, 0 deletions
diff --git a/libgamma_linux_drm_crtc_set_gamma_ramps16.c b/libgamma_linux_drm_crtc_set_gamma_ramps16.c
new file mode 100644
index 0000000..9691581
--- /dev/null
+++ b/libgamma_linux_drm_crtc_set_gamma_ramps16.c
@@ -0,0 +1,54 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+/**
+ * Set the gamma ramps for a CRTC, 16-bit gamma-depth version
+ * 
+ * @param   this   The CRTC state
+ * @param   ramps  The gamma ramps to apply
+ * @return         Zero on success, otherwise (negative) the value of an
+ *                 error identifier provided by this library
+ */
+int
+libgamma_linux_drm_crtc_set_gamma_ramps16(libgamma_crtc_state_t *restrict this, const libgamma_gamma_ramps16_t *restrict ramps)
+{
+	libgamma_drm_card_data_t *restrict card = this->partition->data;
+	int r;
+#ifdef DEBUG
+	/* Gamma ramp sizes are identical but not fixed */
+	if (ramps->red_size != ramps->green_size || ramps->red_size != ramps->blue_size)
+		return LIBGAMMA_MIXED_GAMMA_RAMP_SIZE;
+#endif
+
+	/* Apply gamma ramps */
+	r = drmModeCrtcSetGamma(card->fd, (uint32_t)(size_t)this->data,
+	                        (uint32_t)ramps->red_size, ramps->red, ramps->green, ramps->blue);
+	/* Check for errors */
+	if (r) {
+		switch (errno) {
+		case EACCES:
+		case EAGAIN:
+		case EIO:
+			/* Permission denied errors must be ignored, because we do not
+			 * have permission to do this while a display server is active.
+			 * We are also checking for some other error codes just in case. */
+		case EBUSY:
+		case EINPROGRESS:
+			/* It is hard to find documentation for DRM (in fact all of this is
+			 * just based on the functions names and some testing,) perhaps we
+			 * could get this if we are updating to fast. */
+			break;
+		case EBADF:
+		case ENODEV:
+		case ENXIO:
+			/* TODO: I have not actually tested removing my graphics card or,
+			 *       monitor but I imagine either of these is what would happen. */
+			return LIBGAMMA_GRAPHICS_CARD_REMOVED;
+
+		default:
+			return LIBGAMMA_ERRNO_SET;
+		}
+	}
+	return 0;
+}