The `power saving policy` DRM property is an optional property that
can be added to a connector by a driver.
This property is for compositors to indicate intent of policy of
whether a driver can use power saving features that may compromise
the experience intended by the compositor.
Acked-by: Leo Li <sunpeng.li@xxxxxxx>
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v3->v4:
* Handle -ENOMEM case too
---
drivers/gpu/drm/drm_connector.c | 48 +++++++++++++++++++++++++++++++++
include/drm/drm_connector.h | 2 ++
include/drm/drm_mode_config.h | 5 ++++
include/uapi/drm/drm_mode.h | 7 +++++
4 files changed, 62 insertions(+)
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 4d2df7f64dc5..f8b3e4dfeb0d 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -961,6 +961,11 @@ static const struct drm_prop_enum_list drm_scaling_mode_enum_list[] = {
{ DRM_MODE_SCALE_ASPECT, "Full aspect" },
};
+static const struct drm_prop_enum_list drm_power_saving_policy_enum_list[] = {
+ { __builtin_ffs(DRM_MODE_REQUIRE_COLOR_ACCURACY) - 1, "Require color accuracy" },
+ { __builtin_ffs(DRM_MODE_REQUIRE_LOW_LATENCY) - 1, "Require low latency" },
+};
+
static const struct drm_prop_enum_list drm_aspect_ratio_enum_list[] = {
{ DRM_MODE_PICTURE_ASPECT_NONE, "Automatic" },
{ DRM_MODE_PICTURE_ASPECT_4_3, "4:3" },
@@ -1499,6 +1504,16 @@ static const u32 dp_colorspaces =
*
* Drivers can set up these properties by calling
* drm_mode_create_tv_margin_properties().
+ * power saving policy:
+ * This property is used to set the power saving policy for the connector.
+ * This property is populated with a bitmask of optional requirements set
+ * by the drm master for the drm driver to respect:
+ * - "Require color accuracy": Disable power saving features that will
+ * affect color fidelity.
+ * For example: Hardware assisted backlight modulation.
+ * - "Require low latency": Disable power saving features that will
+ * affect latency.
+ * For example: Panel self refresh (PSR)
*/
int drm_connector_create_standard_properties(struct drm_device *dev)
@@ -1963,6 +1978,39 @@ int drm_mode_create_scaling_mode_property(struct drm_device *dev)
}
EXPORT_SYMBOL(drm_mode_create_scaling_mode_property);
+/**
+ * drm_mode_create_power_saving_policy_property - create power saving policy property
+ * @dev: DRM device
+ * @supported_policies: bitmask of supported power saving policies
+ *
+ * Called by a driver the first time it's needed, must be attached to desired
+ * connectors.
+ *
+ * Returns: %0
+ */
+int drm_mode_create_power_saving_policy_property(struct drm_device *dev,
+ uint64_t supported_policies)
+{
+ struct drm_property *power_saving;
+
+ if (dev->mode_config.power_saving_policy)
+ return 0;
+ WARN_ON((supported_policies & DRM_MODE_POWER_SAVING_POLICY_ALL) == 0);
+
+ power_saving =
+ drm_property_create_bitmask(dev, 0, "power saving policy",
+ drm_power_saving_policy_enum_list,
+ ARRAY_SIZE(drm_power_saving_policy_enum_list),
+ supported_policies);
+ if (!power_saving)
+ return -ENOMEM;
+
+ dev->mode_config.power_saving_policy = power_saving;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_mode_create_power_saving_policy_property);
+
/**
* DOC: Variable refresh properties
*
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index fe88d7fc6b8f..b0ec2ec48de7 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -2025,6 +2025,8 @@ int drm_mode_create_dp_colorspace_property(struct drm_connector *connector,
u32 supported_colorspaces);
int drm_mode_create_content_type_property(struct drm_device *dev);
int drm_mode_create_suggested_offset_properties(struct drm_device *dev);
+int drm_mode_create_power_saving_policy_property(struct drm_device *dev,
+ uint64_t supported_policies);
int drm_connector_set_path_property(struct drm_connector *connector,
const char *path);
diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index 973119a9176b..32077e701e2f 100644
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -954,6 +954,11 @@ struct drm_mode_config {
*/
struct drm_atomic_state *suspend_state;
+ /**
+ * @power_saving_policy: bitmask for power saving policy requests.
+ */
+ struct drm_property *power_saving_policy;
+
const struct drm_mode_config_helper_funcs *helper_private;
};
diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
index 7040e7ea80c7..c2c86623552c 100644
--- a/include/uapi/drm/drm_mode.h
+++ b/include/uapi/drm/drm_mode.h
@@ -152,6 +152,13 @@ extern "C" {
#define DRM_MODE_SCALE_CENTER 2 /* Centered, no scaling */
#define DRM_MODE_SCALE_ASPECT 3 /* Full screen, preserve aspect */
+/* power saving policy options */
+#define DRM_MODE_REQUIRE_COLOR_ACCURACY BIT(0) /* Compositor requires color accuracy */
+#define DRM_MODE_REQUIRE_LOW_LATENCY BIT(1) /* Compositor requires low latency */
+
+#define DRM_MODE_POWER_SAVING_POLICY_ALL (DRM_MODE_REQUIRE_COLOR_ACCURACY |\
+ DRM_MODE_REQUIRE_LOW_LATENCY)
+
/* Dithering mode options */
#define DRM_MODE_DITHERING_OFF 0
#define DRM_MODE_DITHERING_ON 1
--
2.43.0
