6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pin-yen Lin <treapking@xxxxxxxxxxxx>
[ Upstream commit 878e845d8db04df9ff3bbbaac09d335b24153704 ]
Commit 2f7b1d8b5505 ("clk: mediatek: Do a runtime PM get on controllers
during probe") enabled runtime PM for all mediatek clock controllers,
but this introduced an issue on the resume path.
If a device resumes earlier than the clock controller and calls
clk_prepare() when runtime PM is enabled on the controller, it will end
up calling clk_pm_runtime_get(). But the subsequent
pm_runtime_resume_and_get() call will fail because the runtime PM is
temporarily disabled during suspend.
To workaround this, introduce a need_runtime_pm flag and only enable it
on mt8183-mfgcfg, which is the driver that observed deadlock previously.
Hopefully mt8183-cfgcfg won't run into the issue at the resume stage
because the GPU should have stopped rendering before the system calls
suspend.
Fixes: 2f7b1d8b5505 ("clk: mediatek: Do a runtime PM get on controllers during probe")
Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240613120357.1043342-1-treapking@xxxxxxxxxxxx
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/clk/mediatek/clk-mt8183-mfgcfg.c | 1 +
drivers/clk/mediatek/clk-mtk.c | 24 ++++++++++++++----------
drivers/clk/mediatek/clk-mtk.h | 2 ++
3 files changed, 17 insertions(+), 10 deletions(-)
diff --git a/drivers/clk/mediatek/clk-mt8183-mfgcfg.c b/drivers/clk/mediatek/clk-mt8183-mfgcfg.c
index ba504e19d4203..62d876e150e11 100644
--- a/drivers/clk/mediatek/clk-mt8183-mfgcfg.c
+++ b/drivers/clk/mediatek/clk-mt8183-mfgcfg.c
@@ -29,6 +29,7 @@ static const struct mtk_gate mfg_clks[] = {
static const struct mtk_clk_desc mfg_desc = {
.clks = mfg_clks,
.num_clks = ARRAY_SIZE(mfg_clks),
+ .need_runtime_pm = true,
};
static const struct of_device_id of_match_clk_mt8183_mfg[] = {
diff --git a/drivers/clk/mediatek/clk-mtk.c b/drivers/clk/mediatek/clk-mtk.c
index bd37ab4d1a9bb..ba1d1c495bc2b 100644
--- a/drivers/clk/mediatek/clk-mtk.c
+++ b/drivers/clk/mediatek/clk-mtk.c
@@ -496,14 +496,16 @@ static int __mtk_clk_simple_probe(struct platform_device *pdev,
}
- devm_pm_runtime_enable(&pdev->dev);
- /*
- * Do a pm_runtime_resume_and_get() to workaround a possible
- * deadlock between clk_register() and the genpd framework.
- */
- r = pm_runtime_resume_and_get(&pdev->dev);
- if (r)
- return r;
+ if (mcd->need_runtime_pm) {
+ devm_pm_runtime_enable(&pdev->dev);
+ /*
+ * Do a pm_runtime_resume_and_get() to workaround a possible
+ * deadlock between clk_register() and the genpd framework.
+ */
+ r = pm_runtime_resume_and_get(&pdev->dev);
+ if (r)
+ return r;
+ }
/* Calculate how many clk_hw_onecell_data entries to allocate */
num_clks = mcd->num_clks + mcd->num_composite_clks;
@@ -585,7 +587,8 @@ static int __mtk_clk_simple_probe(struct platform_device *pdev,
goto unregister_clks;
}
- pm_runtime_put(&pdev->dev);
+ if (mcd->need_runtime_pm)
+ pm_runtime_put(&pdev->dev);
return r;
@@ -618,7 +621,8 @@ static int __mtk_clk_simple_probe(struct platform_device *pdev,
if (mcd->shared_io && base)
iounmap(base);
- pm_runtime_put(&pdev->dev);
+ if (mcd->need_runtime_pm)
+ pm_runtime_put(&pdev->dev);
return r;
}
diff --git a/drivers/clk/mediatek/clk-mtk.h b/drivers/clk/mediatek/clk-mtk.h
index 22096501a60a7..c17fe1c2d732d 100644
--- a/drivers/clk/mediatek/clk-mtk.h
+++ b/drivers/clk/mediatek/clk-mtk.h
@@ -237,6 +237,8 @@ struct mtk_clk_desc {
int (*clk_notifier_func)(struct device *dev, struct clk *clk);
unsigned int mfg_clk_idx;
+
+ bool need_runtime_pm;
};
int mtk_clk_pdev_probe(struct platform_device *pdev);
--
2.43.0
