From: Archit Taneja <architt@codeaurora.org>
Date: Fri, 6 Oct 2017 16:27:06 +0530
Subject: drm/msm/dsi: Use correct pm_runtime_put variant during host_init
Git-commit: a18a0ea0096833ecb52053b183fcf9709f7bafd8
Patch-mainline: v4.14-rc5
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

The DSI runtime PM suspend/resume callbacks check whether
msm_host->cfg_hnd is non-NULL before trying to enable the bus clocks.
This is done to accommodate early calls to these functions that may
happen before the bus clocks are even initialized.

Calling pm_runtime_put_autosuspend() in dsi_host_init() can result in
racy behaviour since msm_host->cfg_hnd is set very soon after. If the
suspend callback happens too late, we end up trying to disable clocks
that were never enabled, resulting in a bunch of WARN_ON splats.

Use pm_runtime_put_sync() so that the suspend callback is called
immediately.

Reported-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/msm/dsi/dsi_host.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -248,7 +248,7 @@ disable_clks:
 	clk_disable_unprepare(ahb_clk);
 disable_gdsc:
 	regulator_disable(gdsc_reg);
-	pm_runtime_put_autosuspend(dev);
+	pm_runtime_put_sync(dev);
 put_clk:
 	clk_put(ahb_clk);
 put_gdsc: