[PATCH v3 0/3] counter: rz-mtu3-cnt: check clock and runtime PM errors

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* [PATCH v3 0/3] counter: rz-mtu3-cnt: check clock and runtime PM errors
@ 2026-09-03  9:07 Li Youhong
  2026-09-03  9:07 ` [PATCH v3 1/3] counter: rz-mtu3-cnt: check clk_prepare_enable() and pm_runtime_set_active() Li Youhong
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Li Youhong @ 2026-09-03  9:07 UTC (permalink / raw)
  To: biju.das.jz, wbg; +Cc: linux-iio, linux-renesas-soc, Li Youhong

From: Li Youhong <liyouhong@kylinos.cn>

v1 checked only clk_prepare_enable() in probe/resume. Reviewers asked
to also handle pm_runtime_set_active() and all runtime PM get call
sites. Split into three patches, including a follow-up for a
pre-existing runtime PM usage leak on counter init failure.

Changes v2->v3:
Link to v2: https://lore.kernel.org/all/20260831054407.1695146-1-dayou5941@163.com/
- Use pm_runtime_resume_and_get() instead of pm_runtime_get_sync()
  plus pm_runtime_put_noidle() on failure

Changes v1->v2
Link to v1: https://lore.kernel.org/all/20260828071123.179670-1-dayou5941@163.com/
- Also check pm_runtime_set_active() in probe
- Check pm_runtime_get_sync() everywhere
- New patch: put runtime PM ref if counter init fails after get

Li Youhong (3):
  counter: rz-mtu3-cnt: check clk_prepare_enable() and
    pm_runtime_set_active()
  counter: rz-mtu3-cnt: check pm_runtime_resume_and_get() return
    values
  counter: rz-mtu3-cnt: put runtime PM ref if counter init fails

 drivers/counter/rz-mtu3-cnt.c | 112 +++++++++++++++++++++++++++-------
 1 file changed, 83 insertions(+), 29 deletions(-)

-- 
2.25.1


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH v3 1/3] counter: rz-mtu3-cnt: check clk_prepare_enable() and pm_runtime_set_active()
  2026-09-03  9:07 [PATCH v3 0/3] counter: rz-mtu3-cnt: check clock and runtime PM errors Li Youhong
@ 2026-09-03  9:07 ` Li Youhong
  2026-09-03  9:07 ` [PATCH v3 2/3] counter: rz-mtu3-cnt: check pm_runtime_resume_and_get() return values Li Youhong
  2026-09-03  9:07 ` [PATCH v3 3/3] counter: rz-mtu3-cnt: put runtime PM ref if counter init fails Li Youhong
  2 siblings, 0 replies; 4+ messages in thread
From: Li Youhong @ 2026-09-03  9:07 UTC (permalink / raw)
  To: biju.das.jz, wbg; +Cc: linux-iio, linux-renesas-soc, Li Youhong

From: Li Youhong <liyouhong@kylinos.cn>

The driver ignored clk_prepare_enable() failures during probe and
runtime resume, and ignored pm_runtime_set_active() failures during
probe. Propagate the errors so probe does not continue with the clock
disabled or an inconsistent runtime PM state, and resume does not
report success falsely.

Fixes: 0be8907359df ("counter: Add Renesas RZ/G2L MTU3a counter driver")
Suggested-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Li Youhong <liyouhong@kylinos.cn>
---
--- a/drivers/counter/rz-mtu3-cnt.c
+++ b/drivers/counter/rz-mtu3-cnt.c
@@ -817,9 +817,7 @@
 {
 	struct clk *const clk = dev_get_drvdata(dev);
 
-	clk_prepare_enable(clk);
-
-	return 0;
+	return clk_prepare_enable(clk);
 }
 
 static DEFINE_RUNTIME_DEV_PM_OPS(rz_mtu3_cnt_pm_ops,
@@ -861,8 +859,14 @@
 
 	mutex_init(&priv->lock);
 	platform_set_drvdata(pdev, priv->clk);
-	clk_prepare_enable(priv->clk);
-	pm_runtime_set_active(&pdev->dev);
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return ret;
+
+	ret = pm_runtime_set_active(&pdev->dev);
+	if (ret)
+		goto disable_clock;
+
 	pm_runtime_enable(&pdev->dev);
 	ret = devm_add_action_or_reset(&pdev->dev, rz_mtu3_cnt_pm_disable, dev);
 	if (ret < 0)


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH v3 2/3] counter: rz-mtu3-cnt: check pm_runtime_resume_and_get() return values
  2026-09-03  9:07 [PATCH v3 0/3] counter: rz-mtu3-cnt: check clock and runtime PM errors Li Youhong
  2026-09-03  9:07 ` [PATCH v3 1/3] counter: rz-mtu3-cnt: check clk_prepare_enable() and pm_runtime_set_active() Li Youhong
@ 2026-09-03  9:07 ` Li Youhong
  2026-09-03  9:07 ` [PATCH v3 3/3] counter: rz-mtu3-cnt: put runtime PM ref if counter init fails Li Youhong
  2 siblings, 0 replies; 4+ messages in thread
From: Li Youhong @ 2026-09-03  9:07 UTC (permalink / raw)
  To: biju.das.jz, wbg; +Cc: linux-iio, linux-renesas-soc, Li Youhong

From: Li Youhong <liyouhong@kylinos.cn>

The driver ignored runtime PM get failures and continued with register
accesses after a failed resume. Switch all call sites to
pm_runtime_resume_and_get() and propagate errors to the caller. That
API already drops the usage count on failure, so the explicit
pm_runtime_put_noidle() pairing used with pm_runtime_get_sync() is
unnecessary.

Fixes: 0be8907359df ("counter: Add Renesas RZ/G2L MTU3a counter driver")
Suggested-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Li Youhong <liyouhong@kylinos.cn>
---
--- a/drivers/counter/rz-mtu3-cnt.c
+++ b/drivers/counter/rz-mtu3-cnt.c
@@ -102,22 +102,25 @@
 	return &priv->ch[ch_id];
 }
 
-static bool rz_mtu3_is_counter_invalid(struct counter_device *counter, int id)
+static int rz_mtu3_validate_counter(struct counter_device *counter, int id)
 {
 	struct rz_mtu3_cnt *const priv = counter_priv(counter);
 	unsigned long tmdr;
+	int ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0)
+		return ret;
 	tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
 	pm_runtime_put(counter->parent);
 
 	if (id == RZ_MTU3_32_BIT_CH && test_bit(RZ_MTU3_TMDR3_LWA, &tmdr))
-		return false;
+		return 0;
 
 	if (id != RZ_MTU3_32_BIT_CH && !test_bit(RZ_MTU3_TMDR3_LWA, &tmdr))
-		return false;
+		return 0;
 
-	return true;
+	return -EBUSY;
 }
 
 static int rz_mtu3_lock_if_counter_is_valid(struct counter_device *counter,
@@ -125,6 +128,8 @@
 					    struct rz_mtu3_cnt *const priv,
 					    int id)
 {
+	int ret;
+
 	mutex_lock(&priv->lock);
 
 	if (ch->is_busy && !priv->count_is_enabled[id]) {
@@ -132,9 +137,10 @@
 		return -EINVAL;
 	}
 
-	if (rz_mtu3_is_counter_invalid(counter, id)) {
+	ret = rz_mtu3_validate_counter(counter, id);
+	if (ret) {
 		mutex_unlock(&priv->lock);
-		return -EBUSY;
+		return ret;
 	}
 
 	return 0;
@@ -165,7 +171,11 @@
 	if (ret)
 		return ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	if (count->id == RZ_MTU3_32_BIT_CH)
 		*val = rz_mtu3_32bit_ch_read(ch, RZ_MTU3_TCNTLW);
 	else
@@ -187,7 +197,11 @@
 	if (ret)
 		return ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	if (count->id == RZ_MTU3_32_BIT_CH)
 		rz_mtu3_32bit_ch_write(ch, RZ_MTU3_TCNTLW, val);
 	else
@@ -203,8 +217,11 @@
 					      enum counter_function *function)
 {
 	u8 timer_mode;
+	int ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0)
+		return ret;
 	timer_mode = rz_mtu3_8bit_ch_read(ch, RZ_MTU3_TMDR1);
 	pm_runtime_put(counter->parent);
 
@@ -279,7 +296,11 @@
 		return -EINVAL;
 	}
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TMDR1, timer_mode);
 	pm_runtime_put(counter->parent);
 	mutex_unlock(&priv->lock);
@@ -300,7 +321,11 @@
 	if (ret)
 		return ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	tsr = rz_mtu3_8bit_ch_read(ch, RZ_MTU3_TSR);
 	pm_runtime_put(counter->parent);
 
@@ -377,7 +402,11 @@
 		return -EINVAL;
 	}
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	if (count->id == RZ_MTU3_32_BIT_CH)
 		rz_mtu3_32bit_ch_write(ch, RZ_MTU3_TGRALW, ceiling);
 	else
@@ -504,7 +533,9 @@
 		goto exit;
 
 	if (enable) {
-		pm_runtime_get_sync(counter->parent);
+		ret = pm_runtime_resume_and_get(counter->parent);
+		if (ret < 0)
+			goto exit;
 		ret = rz_mtu3_initialize_counter(counter, count->id);
 		if (ret == 0)
 			priv->count_is_enabled[count->id] = true;
@@ -543,7 +574,11 @@
 	if (ret)
 		return ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
 	pm_runtime_put(counter->parent);
 	*cascade_enable = test_bit(RZ_MTU3_TMDR3_LWA, &tmdr);
@@ -562,7 +597,11 @@
 	if (ret)
 		return ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	rz_mtu3_shared_reg_update_bit(priv->ch, RZ_MTU3_TMDR3,
 				      RZ_MTU3_TMDR3_LWA, cascade_enable);
 	pm_runtime_put(counter->parent);
@@ -582,7 +621,11 @@
 	if (ret)
 		return ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3);
 	pm_runtime_put(counter->parent);
 	*ext_input_phase_clock_select = test_bit(RZ_MTU3_TMDR3_PHCKSEL, &tmdr);
@@ -601,7 +644,11 @@
 	if (ret)
 		return ret;
 
-	pm_runtime_get_sync(counter->parent);
+	ret = pm_runtime_resume_and_get(counter->parent);
+	if (ret < 0) {
+		mutex_unlock(&priv->lock);
+		return ret;
+	}
 	rz_mtu3_shared_reg_update_bit(priv->ch, RZ_MTU3_TMDR3,
 				      RZ_MTU3_TMDR3_PHCKSEL,
 				      ext_input_phase_clock_select);


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH v3 3/3] counter: rz-mtu3-cnt: put runtime PM ref if counter init fails
  2026-09-03  9:07 [PATCH v3 0/3] counter: rz-mtu3-cnt: check clock and runtime PM errors Li Youhong
  2026-09-03  9:07 ` [PATCH v3 1/3] counter: rz-mtu3-cnt: check clk_prepare_enable() and pm_runtime_set_active() Li Youhong
  2026-09-03  9:07 ` [PATCH v3 2/3] counter: rz-mtu3-cnt: check pm_runtime_resume_and_get() return values Li Youhong
@ 2026-09-03  9:07 ` Li Youhong
  2 siblings, 0 replies; 4+ messages in thread
From: Li Youhong @ 2026-09-03  9:07 UTC (permalink / raw)
  To: biju.das.jz, wbg; +Cc: linux-iio, linux-renesas-soc, Li Youhong

From: Li Youhong <liyouhong@kylinos.cn>

Counter enable takes a runtime PM reference before initialization but
only puts it on disable. Drop the reference if initialization fails.

Fixes: 0be8907359df ("counter: Add Renesas RZ/G2L MTU3a counter driver")
Signed-off-by: Li Youhong <liyouhong@kylinos.cn>
---
--- a/drivers/counter/rz-mtu3-cnt.c
+++ b/drivers/counter/rz-mtu3-cnt.c
@@ -537,8 +537,11 @@
 		if (ret < 0)
 			goto exit;
 		ret = rz_mtu3_initialize_counter(counter, count->id);
-		if (ret == 0)
-			priv->count_is_enabled[count->id] = true;
+		if (ret < 0) {
+			pm_runtime_put(counter->parent);
+			goto exit;
+		}
+		priv->count_is_enabled[count->id] = true;
 	} else {
 		rz_mtu3_terminate_counter(counter, count->id);
 		priv->count_is_enabled[count->id] = false;


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2026-09-03  9:07 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2026-09-03  9:07 [PATCH v3 0/3] counter: rz-mtu3-cnt: check clock and runtime PM errors Li Youhong
2026-09-03  9:07 ` [PATCH v3 1/3] counter: rz-mtu3-cnt: check clk_prepare_enable() and pm_runtime_set_active() Li Youhong
2026-09-03  9:07 ` [PATCH v3 2/3] counter: rz-mtu3-cnt: check pm_runtime_resume_and_get() return values Li Youhong
2026-09-03  9:07 ` [PATCH v3 3/3] counter: rz-mtu3-cnt: put runtime PM ref if counter init fails Li Youhong

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