[PATCH 1/2] drm/msm/dsi: Use correct pm_runtime_put variant during host_init

[Archit Taneja]

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 at linaro.org>
Signed-off-by: Archit Taneja <architt at codeaurora.org>
---
 drivers/gpu/drm/msm/dsi/dsi_host.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index dbb31a014419..deaf869374ea 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -248,7 +248,7 @@ static const struct msm_dsi_cfg_handler *dsi_get_config(
 	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:
-- 
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