[PATCH v2 28/28] drm/bridge: sii902x: Implement hw state readout
From: Maxime Ripard
Date: Thu Apr 23 2026 - 06:31:39 EST
Implement the hardware state readout for the sii902x bridge
now that all the infrastructure is in place.
Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
---
drivers/gpu/drm/bridge/sii902x.c | 56 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 55 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 12497f5ce4ff..4ad0fdfc1c38 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -20,10 +20,12 @@
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/clk.h>
#include <drm/drm_atomic_helper.h>
+#include <drm/drm_atomic_sro.h>
+#include <drm/drm_atomic_sro_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_drv.h>
#include <drm/drm_edid.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
@@ -535,17 +537,68 @@ sii902x_bridge_mode_valid(struct drm_bridge *bridge,
return MODE_CLOCK_HIGH;
return MODE_OK;
}
+static int
+sii902x_bridge_connector_readout(struct drm_bridge *bridge,
+ struct drm_atomic_sro_state *state,
+ struct drm_connector_state *conn_state)
+{
+ struct sii902x *sii902x = bridge_to_sii902x(bridge);
+ struct drm_connector *connector = conn_state->connector;
+ struct drm_crtc_state *crtc_state;
+ struct drm_encoder *encoder;
+ struct drm_crtc *crtc;
+
+ if (regmap_test_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA, SII902X_SYS_CTRL_PWR_DWN))
+ return 0;
+
+ encoder = bridge->encoder;
+ crtc = encoder->funcs->atomic_sro_get_current_crtc(encoder);
+ if (!crtc)
+ return -ENODEV;
+
+ crtc_state = drm_atomic_sro_get_crtc_state(state, crtc);
+ if (!crtc_state)
+ return -ENODEV;
+
+ crtc_state->encoder_mask |= drm_encoder_mask(encoder);
+ crtc_state->connector_mask |= drm_connector_mask(connector);
+
+ conn_state->crtc = crtc;
+ conn_state->best_encoder = encoder;
+
+ return 0;
+}
+
+static int sii902x_bridge_readout_state(struct drm_bridge *bridge,
+ struct drm_atomic_sro_state *state,
+ struct drm_bridge_state *bridge_state,
+ struct drm_crtc_state *crtc_state,
+ struct drm_connector_state *conn_state)
+{
+ struct sii902x *sii902x = bridge_to_sii902x(bridge);
+
+ if (regmap_test_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA, SII902X_SYS_CTRL_PWR_DWN))
+ return 0;
+
+ /* bridge_state is pretty trivial, we don't have anything to do here */
+
+ return 0;
+}
+
static const struct drm_bridge_funcs sii902x_bridge_funcs = {
.attach = sii902x_bridge_attach,
.mode_set = sii902x_bridge_mode_set,
.atomic_disable = sii902x_bridge_atomic_disable,
.atomic_enable = sii902x_bridge_atomic_enable,
.detect = sii902x_bridge_detect,
.edid_read = sii902x_bridge_edid_read,
+ .atomic_sro_compare_state = drm_atomic_helper_bridge_compare_state,
+ .atomic_sro_readout_state = sii902x_bridge_readout_state,
+ .atomic_sro_connector_readout = sii902x_bridge_connector_readout,
.atomic_reset = drm_atomic_helper_bridge_reset,
.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
.atomic_get_input_bus_fmts = sii902x_bridge_atomic_get_input_bus_fmts,
.atomic_check = sii902x_bridge_atomic_check,
@@ -1131,11 +1184,12 @@ static int sii902x_init(struct sii902x *sii902x)
if (ret)
goto err_unreg_audio;
sii902x->bridge.of_node = dev->of_node;
sii902x->bridge.timings = &default_sii902x_timings;
- sii902x->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID;
+ sii902x->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID |
+ DRM_BRIDGE_OP_CONNECTOR_HW_READOUT;
sii902x->bridge.type = DRM_MODE_CONNECTOR_HDMIA;
if (sii902x->i2c->irq > 0)
sii902x->bridge.ops |= DRM_BRIDGE_OP_HPD;
--
2.53.0