[ConfigStore] Add getCompositionPreference.
In order to tell renderer to render into the best color space with the right
pixel format. We need to expose it as a composition preference. This patch adds
ConfigStore API to query such preference.
Typically, this API will return the default data space of a color space that
the panel is calibrated to, with the default pixel format that hardware
composer can composite to efficiently. However, devices can make tradeoff
between data space and pixel format.
BUG: 113530681
Test: Build, flash, boot
Change-Id: I0ea09e21e70843b50157ec617c87a42bb4ff7332
diff --git a/configstore/1.2/ISurfaceFlingerConfigs.hal b/configstore/1.2/ISurfaceFlingerConfigs.hal
index c32cc82..c879155 100644
--- a/configstore/1.2/ISurfaceFlingerConfigs.hal
+++ b/configstore/1.2/ISurfaceFlingerConfigs.hal
@@ -15,6 +15,8 @@
*/
package android.hardware.configstore@1.2;
+import android.hardware.graphics.common@1.1::Dataspace;
+import android.hardware.graphics.common@1.1::PixelFormat;
import @1.1::ISurfaceFlingerConfigs;
import @1.0::OptionalBool;
@@ -30,4 +32,27 @@
* return true.
*/
useColorManagement() generates (OptionalBool value);
+
+ /**
+ * Returns the default data space and default pixel format that
+ * SurfaceFlinger expects to receive and output.
+ * To determine the default data space and default pixel format,
+ * there are a few things we recommend to consider:
+ *
+ * 1. Hardware composer's capability to composite contents with the
+ * data space and pixel format efficiently;
+ * 2. Hardware composer's ability to composite contents when sRGB contents
+ * and the chosen data space contents coexist;
+ * 3. For better blending, consider using pixel format where the alpha
+ * channel has as many bits as the RGB color channel.
+ *
+ * @return dataSpace is the default data space that SurfaceFlinger expects.
+ * The data space must not be Dataspace::UNKNOWN, if unspecified,
+ * the default data space is Dataspace::V0_SRGB;
+ * @return pixelFormat is the default pixel format that SurfaceFlinger
+ * expects. If unspecified, the default pixel format is
+ * PixelFormat::RGBA_8888.
+ */
+ getCompositionPreference()
+ generates (Dataspace dataSpace, PixelFormat pixelFormat);
};