[PATCH 4.19 16/86] drm/msm/dsi: save pll state before dsi host is powered off

From: Greg Kroah-Hartman
Date: Tue Mar 10 2020 - 09:11:50 EST


From: Harigovindan P <harigovi@xxxxxxxxxxxxxx>

[ Upstream commit a1028dcfd0dd97884072288d0c8ed7f30399b528 ]

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

Signed-off-by: Harigovindan P <harigovi@xxxxxxxxxxxxxx>
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
index bd66d2aac41f7..b01762a7778ae 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
@@ -471,6 +471,7 @@ 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;

@@ -511,6 +512,10 @@ 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);
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
index 9a9fa0c75a131..c630871de7c5b 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c
@@ -726,10 +726,6 @@ 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);
--
2.20.1