[PATCH] drm: bridge: dw_hdmi: Fix ELD is not updated issue

From: Sandor Yu
Date: Tue Jul 25 2023 - 21:49:26 EST


The ELD (EDID-Like Data) is not updated when the HDMI cable
is plugged into different HDMI monitors.
This is because the EDID is not updated in the HDMI HPD function.
As a result, the ELD data remains unchanged and may not reflect
the capabilities of the newly connected HDMI sink device.

To address this issue, the handle_plugged_change function should move to
the bridge_atomic_enable and bridge_atomic_disable functions.
Make sure the EDID is properly updated before updating ELD.

Signed-off-by: Sandor Yu <Sandor.yu@xxxxxxx>
---
drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 21 ++++-----------------
1 file changed, 4 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index 9a3db5234a0e0..6fa4848591226 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -196,7 +196,6 @@ struct dw_hdmi {

hdmi_codec_plugged_cb plugged_cb;
struct device *codec_dev;
- enum drm_connector_status last_connector_result;
};

#define HDMI_IH_PHY_STAT0_RX_SENSE \
@@ -235,7 +234,7 @@ int dw_hdmi_set_plugged_cb(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb fn,
mutex_lock(&hdmi->mutex);
hdmi->plugged_cb = fn;
hdmi->codec_dev = codec_dev;
- plugged = hdmi->last_connector_result == connector_status_connected;
+ plugged = hdmi->connector.status == connector_status_connected;
handle_plugged_change(hdmi, plugged);
mutex_unlock(&hdmi->mutex);

@@ -2446,20 +2445,7 @@ static void dw_hdmi_update_phy_mask(struct dw_hdmi *hdmi)

static enum drm_connector_status dw_hdmi_detect(struct dw_hdmi *hdmi)
{
- enum drm_connector_status result;
-
- result = hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
-
- mutex_lock(&hdmi->mutex);
- if (result != hdmi->last_connector_result) {
- dev_dbg(hdmi->dev, "read_hpd result: %d", result);
- handle_plugged_change(hdmi,
- result == connector_status_connected);
- hdmi->last_connector_result = result;
- }
- mutex_unlock(&hdmi->mutex);
-
- return result;
+ return hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
}

static struct edid *dw_hdmi_get_edid(struct dw_hdmi *hdmi,
@@ -2958,6 +2944,7 @@ static void dw_hdmi_bridge_atomic_disable(struct drm_bridge *bridge,
hdmi->curr_conn = NULL;
dw_hdmi_update_power(hdmi);
dw_hdmi_update_phy_mask(hdmi);
+ handle_plugged_change(hdmi, false);
mutex_unlock(&hdmi->mutex);
}

@@ -2976,6 +2963,7 @@ static void dw_hdmi_bridge_atomic_enable(struct drm_bridge *bridge,
hdmi->curr_conn = connector;
dw_hdmi_update_power(hdmi);
dw_hdmi_update_phy_mask(hdmi);
+ handle_plugged_change(hdmi, true);
mutex_unlock(&hdmi->mutex);
}

@@ -3369,7 +3357,6 @@ struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
hdmi->rxsense = true;
hdmi->phy_mask = (u8)~(HDMI_PHY_HPD | HDMI_PHY_RX_SENSE);
hdmi->mc_clkdis = 0x7f;
- hdmi->last_connector_result = connector_status_disconnected;

mutex_init(&hdmi->mutex);
mutex_init(&hdmi->audio_mutex);
--
2.34.1