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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
drm/connector: hdmi: Add custom hook to filter TMDS character rate
Most of the HDMI controllers have an upper TMDS character rate limit
they can't exceed. On "embedded"-grade display controllers, it will
typically be lower than what high-grade monitors can provide these days,
so drivers will filter the TMDS character rate based on the controller
capabilities.
To make that easier to handle for drivers, let's provide an optional
hook to be implemented by drivers so they can tell the HDMI controller
helpers if a given TMDS character rate is reachable for them or not.
This will then be useful to figure out the best format and bpc count for
a given mode.
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240527-kms-hdmi-connector-state-v15-13-c5af16c3aae2@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>
+62
+9
drivers/gpu/drm/display/drm_hdmi_state_helper.c
+9
drivers/gpu/drm/display/drm_hdmi_state_helper.c
···
53
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const struct drm_display_mode *mode,
54
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unsigned long long clock)
55
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{
56
+
const struct drm_connector_hdmi_funcs *funcs = connector->hdmi.funcs;
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const struct drm_display_info *info = &connector->display_info;
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if (info->max_tmds_clock && clock > info->max_tmds_clock * 1000)
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return MODE_CLOCK_HIGH;
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+
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+
if (funcs && funcs->tmds_char_rate_valid) {
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enum drm_mode_status status;
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+
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status = funcs->tmds_char_rate_valid(connector, mode, clock);
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if (status != MODE_OK)
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return status;
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}
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return MODE_OK;
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}
+4
drivers/gpu/drm/drm_connector.c
+4
drivers/gpu/drm/drm_connector.c
···
457
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* @dev: DRM device
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* @connector: A pointer to the HDMI connector to init
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* @funcs: callbacks for this connector
460
+
* @hdmi_funcs: HDMI-related callbacks for this connector
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* @connector_type: user visible type of the connector
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* @ddc: optional pointer to the associated ddc adapter
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* @supported_formats: Bitmask of @hdmi_colorspace listing supported output formats
···
477
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int drmm_connector_hdmi_init(struct drm_device *dev,
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struct drm_connector *connector,
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const struct drm_connector_funcs *funcs,
479
+
const struct drm_connector_hdmi_funcs *hdmi_funcs,
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int connector_type,
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struct i2c_adapter *ddc,
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unsigned long supported_formats,
···
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if (max_bpc > 8)
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drm_connector_attach_hdr_output_metadata_property(connector);
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+
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connector->hdmi.funcs = hdmi_funcs;
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return 0;
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}
+14
drivers/gpu/drm/tests/drm_connector_test.c
+14
drivers/gpu/drm/tests/drm_connector_test.c
···
24
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struct i2c_adapter ddc;
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};
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+
static const struct drm_connector_hdmi_funcs dummy_hdmi_funcs = {
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+
};
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+
27
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static const struct drm_connector_funcs dummy_funcs = {
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.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
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.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
···
192
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ret = drmm_connector_hdmi_init(&priv->drm, &priv->connector,
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&dummy_funcs,
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&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
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&priv->ddc,
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BIT(HDMI_COLORSPACE_RGB),
···
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ret = drmm_connector_hdmi_init(&priv->drm, &priv->connector,
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&dummy_funcs,
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+
&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
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NULL,
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BIT(HDMI_COLORSPACE_RGB),
···
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ret = drmm_connector_hdmi_init(&priv->drm, &priv->connector,
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&dummy_funcs,
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&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
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&priv->ddc,
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BIT(HDMI_COLORSPACE_RGB),
···
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ret = drmm_connector_hdmi_init(&priv->drm, &priv->connector,
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&dummy_funcs,
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+
&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
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&priv->ddc,
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BIT(HDMI_COLORSPACE_RGB),
···
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ret = drmm_connector_hdmi_init(&priv->drm, connector,
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&dummy_funcs,
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+
&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
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&priv->ddc,
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BIT(HDMI_COLORSPACE_RGB),
···
313
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ret = drmm_connector_hdmi_init(&priv->drm, connector,
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&dummy_funcs,
308
+
&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
317
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&priv->ddc,
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BIT(HDMI_COLORSPACE_RGB),
···
353
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ret = drmm_connector_hdmi_init(&priv->drm, connector,
355
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&dummy_funcs,
347
+
&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
357
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&priv->ddc,
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BIT(HDMI_COLORSPACE_RGB),
···
388
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ret = drmm_connector_hdmi_init(&priv->drm, &priv->connector,
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&dummy_funcs,
381
+
&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
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&priv->ddc,
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0,
···
407
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408
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ret = drmm_connector_hdmi_init(&priv->drm, &priv->connector,
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&dummy_funcs,
399
+
&dummy_hdmi_funcs,
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DRM_MODE_CONNECTOR_HDMIA,
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&priv->ddc,
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BIT(HDMI_COLORSPACE_YUV422),
···
427
415
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ret = drmm_connector_hdmi_init(&priv->drm, &priv->connector,
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&dummy_funcs,
418
+
&dummy_hdmi_funcs,
430
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connector_type,
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&priv->ddc,
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BIT(HDMI_COLORSPACE_RGB),
···
461
448
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ret = drmm_connector_hdmi_init(&priv->drm, &priv->connector,
463
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&dummy_funcs,
451
+
&dummy_hdmi_funcs,
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connector_type,
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&priv->ddc,
466
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BIT(HDMI_COLORSPACE_RGB),
+4
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
+4
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
···
112
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return 0;
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}
114
114
115
+
static const struct drm_connector_hdmi_funcs dummy_connector_hdmi_funcs = {
116
+
};
117
+
115
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static int dummy_connector_get_modes(struct drm_connector *connector)
116
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{
117
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struct drm_atomic_helper_connector_hdmi_priv *priv =
···
197
194
conn = &priv->connector;
198
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ret = drmm_connector_hdmi_init(drm, conn,
199
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&dummy_connector_funcs,
197
+
&dummy_connector_hdmi_funcs,
200
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DRM_MODE_CONNECTOR_HDMIA,
201
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NULL,
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formats,
+31
include/drm/drm_connector.h
+31
include/drm/drm_connector.h
···
38
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struct drm_modeset_acquire_ctx;
39
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struct drm_device;
40
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struct drm_crtc;
41
+
struct drm_display_mode;
41
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struct drm_encoder;
42
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struct drm_panel;
43
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struct drm_property;
···
1059
1058
};
1060
1059
1061
1060
/**
1061
+
* struct drm_connector_hdmi_funcs - drm_hdmi_connector control functions
1062
+
*/
1063
+
struct drm_connector_hdmi_funcs {
1064
+
/**
1065
+
* @tmds_char_rate_valid:
1066
+
*
1067
+
* This callback is invoked at atomic_check time to figure out
1068
+
* whether a particular TMDS character rate is supported by the
1069
+
* driver.
1070
+
*
1071
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* The @tmds_char_rate_valid callback is optional.
1072
+
*
1073
+
* Returns:
1074
+
*
1075
+
* Either &drm_mode_status.MODE_OK or one of the failure reasons
1076
+
* in &enum drm_mode_status.
1077
+
*/
1078
+
enum drm_mode_status
1079
+
(*tmds_char_rate_valid)(const struct drm_connector *connector,
1080
+
const struct drm_display_mode *mode,
1081
+
unsigned long long tmds_rate);
1082
+
};
1083
+
1084
+
/**
1062
1085
* struct drm_connector_funcs - control connectors on a given device
1063
1086
*
1064
1087
* Each CRTC may have one or more connectors attached to it. The functions
···
1954
1929
* supported by the controller.
1955
1930
*/
1956
1931
unsigned long supported_formats;
1932
+
1933
+
/**
1934
+
* @funcs: HDMI connector Control Functions
1935
+
*/
1936
+
const struct drm_connector_hdmi_funcs *funcs;
1957
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} hdmi;
1958
1938
};
1959
1939
···
1981
1951
int drmm_connector_hdmi_init(struct drm_device *dev,
1982
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struct drm_connector *connector,
1983
1953
const struct drm_connector_funcs *funcs,
1954
+
const struct drm_connector_hdmi_funcs *hdmi_funcs,
1984
1955
int connector_type,
1985
1956
struct i2c_adapter *ddc,
1986
1957
unsigned long supported_formats,