From: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Despite the SN65DSI86 being an eDP bridge, on some systems its output is
routed to a DisplayPort connector. Enable DisplayPort mode when the next
component in the display pipeline is detected as a DisplayPort
connector, and disable eDP features in that case.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Reworked to set bridge type based on the next bridge/connector.
Signed-off-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx>
--
Changes since v1/RFC:
- Rebased on top of "drm/bridge: ti-sn65dsi86: switch to
devm_drm_of_get_bridge"
- eDP/DP mode determined from the next bridge connector type.
Changes since v2:
- Remove setting of Standard DP Scrambler Seed. (It's read-only).
- Prevent setting DP_EDP_CONFIGURATION_SET in
ti_sn_bridge_atomic_enable()
- Use Doug's suggested text for disabling ASSR on DP mode.
Changes since v3:
- Remove ASSR_CONTROL definition
Changes since v4:
- Refactor code to configure the DP/eDP scrambler in one place.
---
drivers/gpu/drm/bridge/ti-sn65dsi86.c | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
index f085a037ff5b..a6b15ea4e84d 100644
--- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
+++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
@@ -92,6 +92,8 @@
#define SN_DATARATE_CONFIG_REG 0x94
#define DP_DATARATE_MASK GENMASK(7, 5)
#define DP_DATARATE(x) ((x) << 5)
+#define SN_TRAINING_SETTING_REG 0x95
+#define SCRAMBLE_DISABLE BIT(4)
#define SN_ML_TX_MODE_REG 0x96
#define ML_TX_MAIN_LINK_OFF 0
#define ML_TX_NORMAL_MODE BIT(0)
@@ -1075,12 +1077,23 @@ static void ti_sn_bridge_atomic_enable(struct drm_bridge *bridge,
/*
* The SN65DSI86 only supports ASSR Display Authentication method and
- * this method is enabled by default. An eDP panel must support this
+ * this method is enabled for eDP panels. An eDP panel must support this
* authentication method. We need to enable this method in the eDP panel
* at DisplayPort address 0x0010A prior to link training.
+ *
+ * As only ASSR is supported by SN65DSI86, for full DisplayPort displays
+ * we need to disable the scrambler.
*/
- drm_dp_dpcd_writeb(&pdata->aux, DP_EDP_CONFIGURATION_SET,
- DP_ALTERNATE_SCRAMBLER_RESET_ENABLE);
+ if (pdata->bridge.type == DRM_MODE_CONNECTOR_eDP) {
+ drm_dp_dpcd_writeb(&pdata->aux, DP_EDP_CONFIGURATION_SET,
+ DP_ALTERNATE_SCRAMBLER_RESET_ENABLE);
+
+ regmap_update_bits(pdata->regmap, SN_TRAINING_SETTING_REG,
+ SCRAMBLE_DISABLE, 0);
+ } else {
+ regmap_update_bits(pdata->regmap, SN_TRAINING_SETTING_REG,
+ SCRAMBLE_DISABLE, SCRAMBLE_DISABLE);
+ }
bpp = ti_sn_bridge_get_bpp(connector);
/* Set the DP output format (18 bpp or 24 bpp) */
@@ -1246,6 +1259,8 @@ static int ti_sn_bridge_probe(struct auxiliary_device *adev,
pdata->bridge.funcs = &ti_sn_bridge_funcs;
pdata->bridge.of_node = np;
+ pdata->bridge.type = pdata->next_bridge->type == DRM_MODE_CONNECTOR_DisplayPort
+ ? DRM_MODE_CONNECTOR_DisplayPort : DRM_MODE_CONNECTOR_eDP;
drm_bridge_add(&pdata->bridge);
--
2.34.1
