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From: Leo Yan <leo.yan@arm.com>
To: Suzuki K Poulose <suzuki.poulose@arm.com>,
	Mike Leach <mike.leach@linaro.org>,
	James Clark <james.clark@linaro.org>,
	Anshuman Khandual <anshuman.khandual@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre Torgue <alexandre.torgue@foss.st.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	linux-stm32@st-md-mailman.stormreply.com
Cc: Leo Yan <leo.yan@arm.com>
Subject: [PATCH v2 9/9] coresight: Refactor runtime PM
Date: Wed, 23 Apr 2025 16:17:26 +0100	[thread overview]
Message-ID: <20250423151726.372561-10-leo.yan@arm.com> (raw)
In-Reply-To: <20250423151726.372561-1-leo.yan@arm.com>

The validation for driver data pointers and clock pointers are redundant
in the runtime PM callbacks.  After a driver's probing, its driver data
and clocks have been initialized successfully, this ensures it is safe
to access driver data and clocks in the runtime PM callbacks.  A corner
case is a clock pointer is NULL, in this case, the clock core layer can
handle it properly.  So remove these redundant checking.

In runtime resume, respect values returned from clock function and add
error handling.

Signed-off-by: Leo Yan <leo.yan@arm.com>
---
 drivers/hwtracing/coresight/coresight-cpu-debug.c  |  8 +++-----
 drivers/hwtracing/coresight/coresight-ctcu-core.c  |  8 ++------
 drivers/hwtracing/coresight/coresight-etb10.c      |  8 ++------
 drivers/hwtracing/coresight/coresight-etm3x-core.c |  8 ++------
 drivers/hwtracing/coresight/coresight-funnel.c     | 21 +++++++++++----------
 drivers/hwtracing/coresight/coresight-replicator.c | 20 +++++++++++---------
 drivers/hwtracing/coresight/coresight-stm.c        | 20 +++++++++++---------
 drivers/hwtracing/coresight/coresight-tpiu.c       | 20 +++++++++++---------
 8 files changed, 53 insertions(+), 60 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-cpu-debug.c b/drivers/hwtracing/coresight/coresight-cpu-debug.c
index 481ffcbed534..dff663ac7805 100644
--- a/drivers/hwtracing/coresight/coresight-cpu-debug.c
+++ b/drivers/hwtracing/coresight/coresight-cpu-debug.c
@@ -731,8 +731,8 @@ static int debug_runtime_suspend(struct device *dev)
 {
 	struct debug_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_disable_unprepare(drvdata->pclk);
+	clk_disable_unprepare(drvdata->pclk);
+
 	return 0;
 }
 
@@ -740,9 +740,7 @@ static int debug_runtime_resume(struct device *dev)
 {
 	struct debug_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_prepare_enable(drvdata->pclk);
-	return 0;
+	return clk_prepare_enable(drvdata->pclk);
 }
 #endif
 
diff --git a/drivers/hwtracing/coresight/coresight-ctcu-core.c b/drivers/hwtracing/coresight/coresight-ctcu-core.c
index 75b5114ef652..c586495e9a08 100644
--- a/drivers/hwtracing/coresight/coresight-ctcu-core.c
+++ b/drivers/hwtracing/coresight/coresight-ctcu-core.c
@@ -278,8 +278,7 @@ static int ctcu_runtime_suspend(struct device *dev)
 {
 	struct ctcu_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->apb_clk))
-		clk_disable_unprepare(drvdata->apb_clk);
+	clk_disable_unprepare(drvdata->apb_clk);
 
 	return 0;
 }
@@ -288,10 +287,7 @@ static int ctcu_runtime_resume(struct device *dev)
 {
 	struct ctcu_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->apb_clk))
-		clk_prepare_enable(drvdata->apb_clk);
-
-	return 0;
+	return clk_prepare_enable(drvdata->apb_clk);
 }
 #endif
 
diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 45c2f8f50a3f..3f3b0eb48fdb 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -807,8 +807,7 @@ static int etb_runtime_suspend(struct device *dev)
 {
 	struct etb_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->atclk);
 
 	return 0;
 }
@@ -817,10 +816,7 @@ static int etb_runtime_resume(struct device *dev)
 {
 	struct etb_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_prepare_enable(drvdata->atclk);
-
-	return 0;
+	return clk_prepare_enable(drvdata->atclk);
 }
 #endif
 
diff --git a/drivers/hwtracing/coresight/coresight-etm3x-core.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c
index adbb134f80e6..615ff743eef0 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c
@@ -925,8 +925,7 @@ static int etm_runtime_suspend(struct device *dev)
 {
 	struct etm_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->atclk);
 
 	return 0;
 }
@@ -935,10 +934,7 @@ static int etm_runtime_resume(struct device *dev)
 {
 	struct etm_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_prepare_enable(drvdata->atclk);
-
-	return 0;
+	return clk_prepare_enable(drvdata->atclk);
 }
 #endif
 
diff --git a/drivers/hwtracing/coresight/coresight-funnel.c b/drivers/hwtracing/coresight/coresight-funnel.c
index 62e5125c37ad..6494a3b5d18e 100644
--- a/drivers/hwtracing/coresight/coresight-funnel.c
+++ b/drivers/hwtracing/coresight/coresight-funnel.c
@@ -283,11 +283,8 @@ static int funnel_runtime_suspend(struct device *dev)
 {
 	struct funnel_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_disable_unprepare(drvdata->atclk);
-
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_disable_unprepare(drvdata->pclk);
+	clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->pclk);
 
 	return 0;
 }
@@ -295,13 +292,17 @@ static int funnel_runtime_suspend(struct device *dev)
 static int funnel_runtime_resume(struct device *dev)
 {
 	struct funnel_drvdata *drvdata = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(drvdata->pclk);
+	if (ret)
+		return ret;
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_prepare_enable(drvdata->pclk);
+	ret = clk_prepare_enable(drvdata->atclk);
+	if (ret)
+		clk_disable_unprepare(drvdata->pclk);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_prepare_enable(drvdata->atclk);
-	return 0;
+	return ret;
 }
 #endif
 
diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
index 56b03e6d8336..8595dc104795 100644
--- a/drivers/hwtracing/coresight/coresight-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-replicator.c
@@ -322,24 +322,26 @@ static int replicator_runtime_suspend(struct device *dev)
 {
 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->pclk);
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_disable_unprepare(drvdata->pclk);
 	return 0;
 }
 
 static int replicator_runtime_resume(struct device *dev)
 {
 	struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
+	int ret;
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_prepare_enable(drvdata->pclk);
+	ret = clk_prepare_enable(drvdata->pclk);
+	if (ret)
+		return ret;
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_prepare_enable(drvdata->atclk);
-	return 0;
+	ret = clk_prepare_enable(drvdata->atclk);
+	if (ret)
+		clk_disable_unprepare(drvdata->pclk);
+
+	return ret;
 }
 #endif
 
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index f17986edac00..f859ab932d22 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -957,24 +957,26 @@ static int stm_runtime_suspend(struct device *dev)
 {
 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->pclk);
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_disable_unprepare(drvdata->pclk);
 	return 0;
 }
 
 static int stm_runtime_resume(struct device *dev)
 {
 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
+	int ret;
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_prepare_enable(drvdata->pclk);
+	ret = clk_prepare_enable(drvdata->pclk);
+	if (ret)
+		return ret;
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_prepare_enable(drvdata->atclk);
-	return 0;
+	ret = clk_prepare_enable(drvdata->atclk);
+	if (ret)
+		clk_disable_unprepare(drvdata->pclk);
+
+	return ret;
 }
 #endif
 
diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
index 4701b34778bd..a68ed6b97bf7 100644
--- a/drivers/hwtracing/coresight/coresight-tpiu.c
+++ b/drivers/hwtracing/coresight/coresight-tpiu.c
@@ -206,24 +206,26 @@ static int tpiu_runtime_suspend(struct device *dev)
 {
 	struct tpiu_drvdata *drvdata = dev_get_drvdata(dev);
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->atclk);
+	clk_disable_unprepare(drvdata->pclk);
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_disable_unprepare(drvdata->pclk);
 	return 0;
 }
 
 static int tpiu_runtime_resume(struct device *dev)
 {
 	struct tpiu_drvdata *drvdata = dev_get_drvdata(dev);
+	int ret;
 
-	if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
-		clk_prepare_enable(drvdata->pclk);
+	ret = clk_prepare_enable(drvdata->pclk);
+	if (ret)
+		return ret;
 
-	if (drvdata && !IS_ERR(drvdata->atclk))
-		clk_prepare_enable(drvdata->atclk);
-	return 0;
+	ret = clk_prepare_enable(drvdata->atclk);
+	if (ret)
+		clk_disable_unprepare(drvdata->pclk);
+
+	return ret;
 }
 #endif
 
-- 
2.34.1


  parent reply	other threads:[~2025-04-23 15:18 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-23 15:17 [PATCH v2 0/9] coresight: Fix and improve clock usage Leo Yan
2025-04-23 15:17 ` [PATCH v2 1/9] coresight: tmc: Support atclk Leo Yan
2025-04-23 15:17 ` [PATCH v2 2/9] coresight: catu: " Leo Yan
2025-04-23 15:17 ` [PATCH v2 3/9] coresight: etm4x: " Leo Yan
2025-04-23 15:17 ` [PATCH v2 4/9] coresight: Disable programming clock properly Leo Yan
2025-05-02  6:10   ` Anshuman Khandual
2025-05-06  9:54     ` Leo Yan
2025-05-07  5:59       ` Anshuman Khandual
2025-04-23 15:17 ` [PATCH v2 5/9] coresight: Disable trace bus " Leo Yan
2025-05-02  6:31   ` Anshuman Khandual
2025-04-23 15:17 ` [PATCH v2 6/9] coresight: Avoid enable programming clock duplicately Leo Yan
2025-05-02  6:38   ` Anshuman Khandual
2025-05-06  9:18     ` Leo Yan
2025-05-07  5:55       ` Anshuman Khandual
2025-04-23 15:17 ` [PATCH v2 7/9] coresight: Consolidate clock enabling Leo Yan
2025-05-05  7:28   ` Anshuman Khandual
2025-05-06 10:53     ` Leo Yan
2025-05-07  5:51       ` Anshuman Khandual
2025-04-23 15:17 ` [PATCH v2 8/9] coresight: Make clock sequence consistent Leo Yan
2025-05-02  6:56   ` Anshuman Khandual
2025-04-23 15:17 ` Leo Yan [this message]
2025-05-02  8:45   ` [PATCH v2 9/9] coresight: Refactor runtime PM Anshuman Khandual
2025-05-06 10:16     ` Leo Yan
2025-05-07  5:39       ` Anshuman Khandual

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