[PATCH] drm/omap: hdmi: fix runtime PM leak in hdmi_pll_enable()

[Haotian Zhang]

hdmi_pll_enable() acquires a runtime PM reference with
pm_runtime_get_sync() and then returns the -ETIMEDOUT error from
hdmi_wp_set_pll_pwr() without releasing it.  The callers of
dss_pll_enable() (hdmi4.c, hdmi5.c, dpi.c and dsi.c) do not call
dss_pll_disable() when enabling fails, so the reference is never
dropped and the HDMI device can no longer be runtime suspended.

Release the runtime PM reference and undo the dss_ctrl_pll_enable()
call on that error path.  Also drop the reference with
pm_runtime_put_noidle() when pm_runtime_get_sync() itself fails.

Fixes: 86c9305c864c ("drm/omap: HDMI PLL: use runtime pm")
Assisted-by: DeepSeek-V4.1-Flash
Signed-off-by: Haotian Zhang <vulab@xxxxxxxxxxx>
---
 drivers/gpu/drm/omapdrm/dss/hdmi_pll.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi_pll.c b/drivers/gpu/drm/omapdrm/dss/hdmi_pll.c
index eea719243eaf..9b900fc88f5f 100644
--- a/drivers/gpu/drm/omapdrm/dss/hdmi_pll.c
+++ b/drivers/gpu/drm/omapdrm/dss/hdmi_pll.c
@@ -43,13 +43,19 @@ static int hdmi_pll_enable(struct dss_pll *dsspll)
 	int r;
 
 	r = pm_runtime_get_sync(&pll->pdev->dev);
-	WARN_ON(r < 0);
+	if (WARN_ON(r < 0)) {
+		pm_runtime_put_noidle(&pll->pdev->dev);
+		return r;
+	}
 
 	dss_ctrl_pll_enable(dsspll, true);
 
 	r = hdmi_wp_set_pll_pwr(wp, HDMI_PLLPWRCMD_BOTHON_ALLCLKS);
-	if (r)
+	if (r) {
+		dss_ctrl_pll_enable(dsspll, false);
+		pm_runtime_put_sync(&pll->pdev->dev);
 		return r;
+	}
 
 	return 0;
 }
-- 
2.25.1