diff options
Diffstat (limited to 'drivers/gpu/drm/msm/dsi/phy/dsi_phy.c')
| -rw-r--r-- | drivers/gpu/drm/msm/dsi/phy/dsi_phy.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c index e8c1a727179c..4eb1f121373f 100644 --- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c +++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy.c @@ -723,6 +723,22 @@ static int dsi_phy_driver_probe(struct platform_device *pdev) phy->pll = NULL; } + /* + * As explained in msm_dsi_phy_enable, resetting the DSI PHY (as done + * in dsi_mgr_phy_enable) silently changes its PLL registers to power-on + * defaults, but the generic clock framework manages and caches several + * of the PLL registers. It initializes these caches at registration + * time via register read. + * + * As a result, we need to save DSI PLL registers once at probe in order + * for the first call to msm_dsi_phy_enable to successfully bring PLL + * registers back in line with what the generic clock framework expects. + * + * Subsequent PLL restores during msm_dsi_phy_enable will always be + * paired with PLL saves in msm_dsi_phy_disable. + */ + msm_dsi_pll_save_state(phy->pll); + dsi_phy_disable_resource(phy); platform_set_drvdata(pdev, phy); |