[PATCH v13 04/28] drm/connector: hdmi: Create an HDMI sub-state

Maxime Ripard
2024-05-07T14:31:02Z

The next features we will need to share across drivers will need to
store some parameters for drivers to use, such as the selected output
format.

Let's create a new connector sub-state dedicated to HDMI controllers,
that will eventually store everything we need.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
drivers/gpu/drm/display/Kconfig | 7 +++++
drivers/gpu/drm/display/Makefile | 2 ++
drivers/gpu/drm/display/drm_hdmi_state_helper.c | 41 +++++++++++++++++++++++++
include/drm/display/drm_hdmi_state_helper.h | 16 ++++++++++
include/drm/drm_connector.h | 7 +++++
5 files changed, 73 insertions(+)

diff --git a/drivers/gpu/drm/display/Kconfig b/drivers/gpu/drm/display/Kconfig
index 864a6488bfdf..14114b597ef4 100644
--- a/drivers/gpu/drm/display/Kconfig
+++ b/drivers/gpu/drm/display/Kconfig
@@ -68,5 +68,12 @@ config DRM_DISPLAY_HDCP_HELPER
config DRM_DISPLAY_HDMI_HELPER
bool
depends on DRM_DISPLAY_HELPER
help
DRM display helpers for HDMI.
+
+config DRM_DISPLAY_HDMI_STATE_HELPER
+ bool
+ depends on DRM_DISPLAY_HELPER
+ depends on DRM_DISPLAY_HDMI_HELPER
+ help
+ DRM KMS state helpers for HDMI.
diff --git a/drivers/gpu/drm/display/Makefile b/drivers/gpu/drm/display/Makefile
index 17d2cc73ff56..629df2f4d322 100644
--- a/drivers/gpu/drm/display/Makefile
+++ b/drivers/gpu/drm/display/Makefile
@@ -12,9 +12,11 @@ drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_TUNNEL) += \
drm_dp_tunnel.o
drm_display_helper-$(CONFIG_DRM_DISPLAY_HDCP_HELPER) += drm_hdcp_helper.o
drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_HELPER) += \
drm_hdmi_helper.o \
drm_scdc_helper.o
+drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_STATE_HELPER) += \
+ drm_hdmi_state_helper.o
drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_AUX_CHARDEV) += drm_dp_aux_dev.o
drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_AUX_CEC) += drm_dp_cec.o

obj-$(CONFIG_DRM_DISPLAY_HELPER) += drm_display_helper.o
diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
new file mode 100644
index 000000000000..1e92c1108d23
--- /dev/null
+++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: MIT
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_connector.h>
+
+#include <drm/display/drm_hdmi_state_helper.h>
+
+/**
+ * __drm_atomic_helper_connector_hdmi_reset() - Initializes all HDMI @drm_connector_state resources
+ * @connector: DRM connector
+ * @new_conn_state: connector state to reset
+ *
+ * Initializes all HDMI resources from a @drm_connector_state without
+ * actually allocating it. This is useful for HDMI drivers, in
+ * combination with __drm_atomic_helper_connector_reset() or
+ * drm_atomic_helper_connector_reset().
+ */
+void __drm_atomic_helper_connector_hdmi_reset(struct drm_connector *connector,
+ struct drm_connector_state *new_conn_state)
+{
+}
+EXPORT_SYMBOL(__drm_atomic_helper_connector_hdmi_reset);
+
+/**
+ * drm_atomic_helper_connector_hdmi_check() - Helper to check HDMI connector atomic state
+ * @connector: DRM Connector
+ * @state: the DRM State object
+ *
+ * Provides a default connector state check handler for HDMI connectors.
+ * Checks that a desired connector update is valid, and updates various
+ * fields of derived state.
+ *
+ * RETURNS:
+ * Zero on success, or an errno code otherwise.
+ */
+int drm_atomic_helper_connector_hdmi_check(struct drm_connector *connector,
+ struct drm_atomic_state *state)
+{
+ return 0;
+}
+EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_check);
diff --git a/include/drm/display/drm_hdmi_state_helper.h b/include/drm/display/drm_hdmi_state_helper.h
new file mode 100644
index 000000000000..6021983e2602
--- /dev/null
+++ b/include/drm/display/drm_hdmi_state_helper.h
@@ -0,0 +1,16 @@
+#/* SPDX-License-Identifier: MIT */
+
+#ifndef DRM_HDMI_STATE_HELPER_H_
+#define DRM_HDMI_STATE_HELPER_H_
+
+struct drm_atomic_state;
+struct drm_connector;
+struct drm_connector_state;
+
+void __drm_atomic_helper_connector_hdmi_reset(struct drm_connector *connector,
+ struct drm_connector_state *new_conn_state);
+
+int drm_atomic_helper_connector_hdmi_check(struct drm_connector *connector,
+ struct drm_atomic_state *state);
+
+#endif // DRM_HDMI_STATE_HELPER_H_
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 4491c4c2fb6e..000a2a156619 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1029,10 +1029,17 @@ struct drm_connector_state {
/**
* @hdr_output_metadata:
* DRM blob property for HDR output metadata
*/
struct drm_property_blob *hdr_output_metadata;
+
+ /**
+ * @hdmi: HDMI-related variable and properties. Filled by
+ * @drm_atomic_helper_connector_hdmi_check().
+ */
+ struct {
+ } hdmi;
};

/**
* struct drm_connector_funcs - control connectors on a given device
*