[PATCH v3 01/38] drm/msm/dp: remove cached drm_edid from panel

[Yongxing Mou <yongxing.mou@oss.qualcomm.com>]

The cached drm_edid in msm_dp_panel was redundant and led to unnecessary
state management complexity. This change removes the drm_edid member from
the panel structure and refactors related functions to use locally read
EDID data instead.

- Replaces msm_dp_panel_read_sink_caps() with msm_dp_panel_read_link_caps()
- Updates msm_dp_panel_handle_sink_request() to accept drm_edid as input
- Removes msm_dp_panel_get_modes() and drm_edid caching logic
- Cleans up unused drm_edid_free() calls

This simplifies EDID handling and avoids stale data issues.

Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/dp/dp_display.c | 28 +++++++++++++++-------
 drivers/gpu/drm/msm/dp/dp_panel.c   | 47 ++++---------------------------------
 drivers/gpu/drm/msm/dp/dp_panel.h   |  9 +++----
 3 files changed, 26 insertions(+), 58 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 6d81950627a073baca9809690134a711e965035f..dadf31bc37763c4f07f68b76fbbe33fb77b20850 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -282,6 +282,7 @@ static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
 	const struct drm_display_info *info = &connector->display_info;
 	int rc = 0;
 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
+	const struct drm_edid *drm_edid;
 
 	rc = drm_dp_read_dpcd_caps(dp->aux, dpcd);
 	if (rc)
@@ -289,7 +290,20 @@ static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
 
 	dp->link->lttpr_count = msm_dp_display_lttpr_init(dp, dpcd);
 
-	rc = msm_dp_panel_read_sink_caps(dp->panel, connector);
+	rc = msm_dp_panel_read_link_caps(dp->panel, connector);
+	if (rc)
+		goto end;
+
+	drm_edid = drm_edid_read_ddc(connector, &dp->aux->ddc);
+	drm_edid_connector_update(connector, drm_edid);
+
+	if (!drm_edid) {
+		DRM_ERROR("panel edid read failed\n");
+		/* check edid read fail is due to unplug */
+		if (!msm_dp_aux_is_link_connected(dp->aux))
+			return -ETIMEDOUT;
+	}
+
 	if (rc)
 		goto end;
 
@@ -306,7 +320,7 @@ static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
 	dp->msm_dp_display.psr_supported = dp->panel->psr_cap.version && psr_enabled;
 
 	dp->audio_supported = info->has_audio;
-	msm_dp_panel_handle_sink_request(dp->panel);
+	msm_dp_panel_handle_sink_request(dp->panel, drm_edid);
 
 	/*
 	 * set sink to normal operation mode -- D0
@@ -565,7 +579,6 @@ static int msm_dp_irq_hpd_handle(struct msm_dp_display_private *dp, u32 data)
 static void msm_dp_display_deinit_sub_modules(struct msm_dp_display_private *dp)
 {
 	msm_dp_audio_put(dp->audio);
-	msm_dp_panel_put(dp->panel);
 	msm_dp_aux_put(dp->aux);
 }
 
@@ -616,7 +629,7 @@ static int msm_dp_init_sub_modules(struct msm_dp_display_private *dp)
 		rc = PTR_ERR(dp->ctrl);
 		DRM_ERROR("failed to initialize ctrl, rc = %d\n", rc);
 		dp->ctrl = NULL;
-		goto error_ctrl;
+		goto error_link;
 	}
 
 	dp->audio = msm_dp_audio_get(dp->msm_dp_display.pdev, dp->link_base);
@@ -624,13 +637,11 @@ static int msm_dp_init_sub_modules(struct msm_dp_display_private *dp)
 		rc = PTR_ERR(dp->audio);
 		pr_err("failed to initialize audio, rc = %d\n", rc);
 		dp->audio = NULL;
-		goto error_ctrl;
+		goto error_link;
 	}
 
 	return rc;
 
-error_ctrl:
-	msm_dp_panel_put(dp->panel);
 error_link:
 	msm_dp_aux_put(dp->aux);
 error:
@@ -794,8 +805,7 @@ int msm_dp_display_get_modes(struct msm_dp *dp)
 
 	msm_dp_display = container_of(dp, struct msm_dp_display_private, msm_dp_display);
 
-	return msm_dp_panel_get_modes(msm_dp_display->panel,
-		dp->connector);
+	return drm_edid_connector_add_modes(msm_dp_display->panel->connector);
 }
 
 bool msm_dp_display_check_video_test(struct msm_dp *dp)
diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c b/drivers/gpu/drm/msm/dp/dp_panel.c
index 15b7f6c7146e1176a80b5c9d25896b1c8ede3aed..eae125972934bb2fb3b716dc47ae71cd0421bd1a 100644
--- a/drivers/gpu/drm/msm/dp/dp_panel.c
+++ b/drivers/gpu/drm/msm/dp/dp_panel.c
@@ -159,7 +159,7 @@ static u32 msm_dp_panel_get_supported_bpp(struct msm_dp_panel *msm_dp_panel,
 	return min_supported_bpp;
 }
 
-int msm_dp_panel_read_sink_caps(struct msm_dp_panel *msm_dp_panel,
+int msm_dp_panel_read_link_caps(struct msm_dp_panel *msm_dp_panel,
 	struct drm_connector *connector)
 {
 	int rc, bw_code;
@@ -201,25 +201,6 @@ int msm_dp_panel_read_sink_caps(struct msm_dp_panel *msm_dp_panel,
 
 	rc = drm_dp_read_downstream_info(panel->aux, msm_dp_panel->dpcd,
 					 msm_dp_panel->downstream_ports);
-	if (rc)
-		return rc;
-
-	drm_edid_free(msm_dp_panel->drm_edid);
-
-	msm_dp_panel->drm_edid = drm_edid_read_ddc(connector, &panel->aux->ddc);
-
-	drm_edid_connector_update(connector, msm_dp_panel->drm_edid);
-
-	if (!msm_dp_panel->drm_edid) {
-		DRM_ERROR("panel edid read failed\n");
-		/* check edid read fail is due to unplug */
-		if (!msm_dp_aux_is_link_connected(panel->aux)) {
-			rc = -ETIMEDOUT;
-			goto end;
-		}
-	}
-
-end:
 	return rc;
 }
 
@@ -246,20 +227,6 @@ u32 msm_dp_panel_get_mode_bpp(struct msm_dp_panel *msm_dp_panel,
 	return bpp;
 }
 
-int msm_dp_panel_get_modes(struct msm_dp_panel *msm_dp_panel,
-	struct drm_connector *connector)
-{
-	if (!msm_dp_panel) {
-		DRM_ERROR("invalid input\n");
-		return -EINVAL;
-	}
-
-	if (msm_dp_panel->drm_edid)
-		return drm_edid_connector_add_modes(connector);
-
-	return 0;
-}
-
 static u8 msm_dp_panel_get_edid_checksum(const struct edid *edid)
 {
 	edid += edid->extensions;
@@ -267,7 +234,8 @@ static u8 msm_dp_panel_get_edid_checksum(const struct edid *edid)
 	return edid->checksum;
 }
 
-void msm_dp_panel_handle_sink_request(struct msm_dp_panel *msm_dp_panel)
+void msm_dp_panel_handle_sink_request(struct msm_dp_panel *msm_dp_panel,
+				      const struct drm_edid *drm_edid)
 {
 	struct msm_dp_panel_private *panel;
 
@@ -280,7 +248,7 @@ void msm_dp_panel_handle_sink_request(struct msm_dp_panel *msm_dp_panel)
 
 	if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
 		/* FIXME: get rid of drm_edid_raw() */
-		const struct edid *edid = drm_edid_raw(msm_dp_panel->drm_edid);
+		const struct edid *edid = drm_edid_raw(drm_edid);
 		u8 checksum;
 
 		if (edid)
@@ -736,10 +704,3 @@ struct msm_dp_panel *msm_dp_panel_get(struct device *dev, struct drm_dp_aux *aux
 	return msm_dp_panel;
 }
 
-void msm_dp_panel_put(struct msm_dp_panel *msm_dp_panel)
-{
-	if (!msm_dp_panel)
-		return;
-
-	drm_edid_free(msm_dp_panel->drm_edid);
-}
diff --git a/drivers/gpu/drm/msm/dp/dp_panel.h b/drivers/gpu/drm/msm/dp/dp_panel.h
index d2cf401506dcbaf553192d5e18c87207337664ab..618d0253b525308b392b9282098e8ca78bf32f1c 100644
--- a/drivers/gpu/drm/msm/dp/dp_panel.h
+++ b/drivers/gpu/drm/msm/dp/dp_panel.h
@@ -33,7 +33,6 @@ struct msm_dp_panel {
 	u8 downstream_ports[DP_MAX_DOWNSTREAM_PORTS];
 
 	struct msm_dp_link_info link_info;
-	const struct drm_edid *drm_edid;
 	struct drm_connector *connector;
 	struct msm_dp_display_mode msm_dp_mode;
 	struct msm_dp_panel_psr psr_cap;
@@ -50,13 +49,12 @@ struct msm_dp_panel {
 int msm_dp_panel_init_panel_info(struct msm_dp_panel *msm_dp_panel);
 int msm_dp_panel_deinit(struct msm_dp_panel *msm_dp_panel);
 int msm_dp_panel_timing_cfg(struct msm_dp_panel *msm_dp_panel, bool wide_bus_en);
-int msm_dp_panel_read_sink_caps(struct msm_dp_panel *msm_dp_panel,
+int msm_dp_panel_read_link_caps(struct msm_dp_panel *msm_dp_panel,
 		struct drm_connector *connector);
 u32 msm_dp_panel_get_mode_bpp(struct msm_dp_panel *msm_dp_panel, u32 mode_max_bpp,
 			u32 mode_pclk_khz);
-int msm_dp_panel_get_modes(struct msm_dp_panel *msm_dp_panel,
-		struct drm_connector *connector);
-void msm_dp_panel_handle_sink_request(struct msm_dp_panel *msm_dp_panel);
+void msm_dp_panel_handle_sink_request(struct msm_dp_panel *msm_dp_panel,
+				      const struct drm_edid *drm_edid);
 void msm_dp_panel_tpg_config(struct msm_dp_panel *msm_dp_panel, bool enable);
 
 void msm_dp_panel_clear_dsc_dto(struct msm_dp_panel *msm_dp_panel);
@@ -95,5 +93,4 @@ struct msm_dp_panel *msm_dp_panel_get(struct device *dev, struct drm_dp_aux *aux
 			      struct msm_dp_link *link,
 			      void __iomem *link_base,
 			      void __iomem *p0_base);
-void msm_dp_panel_put(struct msm_dp_panel *msm_dp_panel);
 #endif /* _DP_PANEL_H_ */

-- 
2.34.1