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drm/msm/dsi: save pll state before dsi host is powered off

PATCH In review Harigovindan P 2 participants 2 messages Feb 6, 2020

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Harigovindan P

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#0 lore raw

PATCH 1/1 drm/msm/dsi: save pll state before dsi host is powered off

Save pll state before dsi host is powered off. Without this change some register values gets resetted.

Signed-off-by Harigovindan P <[email protected]>

---

Changes in v1:
- Saving pll state before dsi host is powered off.
- Removed calling of save state in post_disable since everything would be resetted and it would save only resetted values.

 drivers/gpu/drm/msm/dsi/dsi_manager.c | 5 +++++
 drivers/gpu/drm/msm/dsi/phy/dsi_phy.c | 4 ----
 2 files changed, 5 insertions(+), 4 deletions(-)
drivers/gpu/drm/msm/dsi/dsi_manager.c +5 -0
index 104115d..a987efe 100644
@@ -506,6 +506,7 @@ static void dsi_mgr_bridge_post_disable(struct drm_bridge *bridge)
 	struct msm_dsi *msm_dsi1 = dsi_mgr_get_dsi(DSI_1);
 	struct mipi_dsi_host *host = msm_dsi->host;
 	struct drm_panel *panel = msm_dsi->panel;
+	struct msm_dsi_pll *src_pll;
 	bool is_dual_dsi = IS_DUAL_DSI();
 	int ret;
 

@@ -539,6 +540,10 @@ static void dsi_mgr_bridge_post_disable(struct drm_bridge *bridge)
 								id, ret);
 	}
 
+	/* Save PLL status if it is a clock source */
+	src_pll = msm_dsi_phy_get_pll(msm_dsi->phy);
+	msm_dsi_pll_save_state(src_pll);
+
 	ret = msm_dsi_host_power_off(host);
 	if (ret)
 		pr_err("%s: host %d power off failed,%d\n", __func__, id, ret);
drivers/gpu/drm/msm/dsi/phy/dsi_phy.c +0 -4
index b0cfa67..f509ebd 100644
@@ -724,10 +724,6 @@ void msm_dsi_phy_disable(struct msm_dsi_phy *phy)
 	if (!phy || !phy->cfg->ops.disable)
 		return;
 
-	/* Save PLL status if it is a clock source */
-	if (phy->usecase != MSM_DSI_PHY_SLAVE)
-		msm_dsi_pll_save_state(phy->pll);
-
 	phy->cfg->ops.disable(phy);
 
 	dsi_phy_regulator_disable(phy);
Signature · 1 line
2.7.4
#1 lore raw
Quoted 3 lines · Harigovindan P

Save pll state before dsi host is powered off. Without this change some register values gets resetted.

The phy driver already does this. Why is the current implementation insufficient?

Quoted 8 lines
Signed-off-by Harigovindan P <[email protected]>

---

Changes in v1:
- Saving pll state before dsi host is powered off.
- Removed calling of save state in post_disable since everything would be resetted and it would save only resetted values.

Removed from post_disable? Thats not what I see in the change since you are adding code to dsi_mgr_bridge_post_disable()