[PATCH v3 4/9] coresight: Appropriately disable programming clocks

From: Leo Yan
Date: Mon Jun 09 2025 - 12:03:12 EST

Some CoreSight components have programming clocks (pclk) and are enabled
using clk_get() and clk_prepare_enable(). However, in many cases, these
clocks are not disabled when modules exit and only released by clk_put().

To fix the issue, this commit refactors coresight_get_enable_apb_pclk()
by replacing clk_get() and clk_prepare_enable() with
devm_clk_get_enabled() for enabling APB clock. Callers are updated
to reuse the returned error value.

With the change, programming clocks are managed as resources in driver
model layer, allowing clock cleanup to be handled automatically. As a
result, manual cleanup operations are no longer needed and are removed
from the Coresight drivers.

Fixes: 73d779a03a76 ("coresight: etm4x: Change etm4_platform_driver driver for MMIO devices")
Signed-off-by: Leo Yan <leo.yan@xxxxxxx>
---
drivers/hwtracing/coresight/coresight-catu.c | 9 ++-------
drivers/hwtracing/coresight/coresight-cpu-debug.c | 6 +-----
drivers/hwtracing/coresight/coresight-ctcu-core.c | 10 ++--------
drivers/hwtracing/coresight/coresight-etm4x-core.c | 9 ++-------
drivers/hwtracing/coresight/coresight-funnel.c | 6 +-----
drivers/hwtracing/coresight/coresight-replicator.c | 6 +-----
drivers/hwtracing/coresight/coresight-stm.c | 4 +---
drivers/hwtracing/coresight/coresight-tmc-core.c | 4 +---
drivers/hwtracing/coresight/coresight-tpiu.c | 4 +---
include/linux/coresight.h | 16 +++-------------
10 files changed, 15 insertions(+), 59 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
index af2a55f0c907c392d092a50612b23c115a1b0f5f..4c345ff2cff141ea63c2220393e5fdd00c449ca6 100644
--- a/drivers/hwtracing/coresight/coresight-catu.c
+++ b/drivers/hwtracing/coresight/coresight-catu.c
@@ -636,7 +636,7 @@ static int catu_platform_probe(struct platform_device *pdev)

drvdata->pclk = coresight_get_enable_apb_pclk(&pdev->dev);
if (IS_ERR(drvdata->pclk))
- return -ENODEV;
+ return PTR_ERR(drvdata->pclk);

pm_runtime_get_noresume(&pdev->dev);
pm_runtime_set_active(&pdev->dev);
@@ -645,11 +645,8 @@ static int catu_platform_probe(struct platform_device *pdev)
dev_set_drvdata(&pdev->dev, drvdata);
ret = __catu_probe(&pdev->dev, res);
pm_runtime_put(&pdev->dev);
- if (ret) {
+ if (ret)
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
- }

return ret;
}
@@ -663,8 +660,6 @@ static void catu_platform_remove(struct platform_device *pdev)

__catu_remove(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}

#ifdef CONFIG_PM
diff --git a/drivers/hwtracing/coresight/coresight-cpu-debug.c b/drivers/hwtracing/coresight/coresight-cpu-debug.c
index a871d997330b09bdb741f35c59108b0b3252cc54..e39dfb886688e111eee95d4294f37fa85baccd14 100644
--- a/drivers/hwtracing/coresight/coresight-cpu-debug.c
+++ b/drivers/hwtracing/coresight/coresight-cpu-debug.c
@@ -699,7 +699,7 @@ static int debug_platform_probe(struct platform_device *pdev)

drvdata->pclk = coresight_get_enable_apb_pclk(&pdev->dev);
if (IS_ERR(drvdata->pclk))
- return -ENODEV;
+ return PTR_ERR(drvdata->pclk);

dev_set_drvdata(&pdev->dev, drvdata);
pm_runtime_get_noresume(&pdev->dev);
@@ -710,8 +710,6 @@ static int debug_platform_probe(struct platform_device *pdev)
if (ret) {
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}
return ret;
}
@@ -725,8 +723,6 @@ static void debug_platform_remove(struct platform_device *pdev)

__debug_remove(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}

#ifdef CONFIG_ACPI
diff --git a/drivers/hwtracing/coresight/coresight-ctcu-core.c b/drivers/hwtracing/coresight/coresight-ctcu-core.c
index c6bafc96db963310b5e77a095953c83a172cfc7c..de279efe340581ceabfb9e1cd1e7fe4b5e4f826e 100644
--- a/drivers/hwtracing/coresight/coresight-ctcu-core.c
+++ b/drivers/hwtracing/coresight/coresight-ctcu-core.c
@@ -209,7 +209,7 @@ static int ctcu_probe(struct platform_device *pdev)

drvdata->apb_clk = coresight_get_enable_apb_pclk(dev);
if (IS_ERR(drvdata->apb_clk))
- return -ENODEV;
+ return PTR_ERR(drvdata->apb_clk);

cfgs = of_device_get_match_data(dev);
if (cfgs) {
@@ -233,12 +233,8 @@ static int ctcu_probe(struct platform_device *pdev)
desc.access = CSDEV_ACCESS_IOMEM(base);

drvdata->csdev = coresight_register(&desc);
- if (IS_ERR(drvdata->csdev)) {
- if (!IS_ERR_OR_NULL(drvdata->apb_clk))
- clk_put(drvdata->apb_clk);
-
+ if (IS_ERR(drvdata->csdev))
return PTR_ERR(drvdata->csdev);
- }

return 0;
}
@@ -275,8 +271,6 @@ static void ctcu_platform_remove(struct platform_device *pdev)

ctcu_remove(pdev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->apb_clk))
- clk_put(drvdata->apb_clk);
}

#ifdef CONFIG_PM
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 205121c14d72ec2f6a193dccb94b7cfd5c314e26..1915da95b93d953a61778a71b4880c87b91fe17a 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -2303,14 +2303,12 @@ static int etm4_probe_platform_dev(struct platform_device *pdev)

drvdata->pclk = coresight_get_enable_apb_pclk(&pdev->dev);
if (IS_ERR(drvdata->pclk))
- return -ENODEV;
+ return PTR_ERR(drvdata->pclk);

if (res) {
drvdata->base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(drvdata->base)) {
- clk_put(drvdata->pclk);
+ if (IS_ERR(drvdata->base))
return PTR_ERR(drvdata->base);
- }
}

dev_set_drvdata(&pdev->dev, drvdata);
@@ -2417,9 +2415,6 @@ static void etm4_remove_platform_dev(struct platform_device *pdev)
if (drvdata)
etm4_remove_dev(drvdata);
pm_runtime_disable(&pdev->dev);
-
- if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}

static const struct amba_id etm4_ids[] = {
diff --git a/drivers/hwtracing/coresight/coresight-funnel.c b/drivers/hwtracing/coresight/coresight-funnel.c
index b1922dbe9292b02c91ca5730998e59ecdb08fdc7..36fc4e991458c112521c4261d73f3e58e9a3f995 100644
--- a/drivers/hwtracing/coresight/coresight-funnel.c
+++ b/drivers/hwtracing/coresight/coresight-funnel.c
@@ -240,7 +240,7 @@ static int funnel_probe(struct device *dev, struct resource *res)

drvdata->pclk = coresight_get_enable_apb_pclk(dev);
if (IS_ERR(drvdata->pclk))
- return -ENODEV;
+ return PTR_ERR(drvdata->pclk);

/*
* Map the device base for dynamic-funnel, which has been
@@ -284,8 +284,6 @@ static int funnel_probe(struct device *dev, struct resource *res)
out_disable_clk:
if (ret && !IS_ERR_OR_NULL(drvdata->atclk))
clk_disable_unprepare(drvdata->atclk);
- if (ret && !IS_ERR_OR_NULL(drvdata->pclk))
- clk_disable_unprepare(drvdata->pclk);
return ret;
}

@@ -355,8 +353,6 @@ static void funnel_platform_remove(struct platform_device *pdev)

funnel_remove(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}

static const struct of_device_id funnel_match[] = {
diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
index 06efd2b01a0f71620eac71166567d14655b58403..6dd24eb10a94b0eb28f4f27afab845227e22b96c 100644
--- a/drivers/hwtracing/coresight/coresight-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-replicator.c
@@ -247,7 +247,7 @@ static int replicator_probe(struct device *dev, struct resource *res)

drvdata->pclk = coresight_get_enable_apb_pclk(dev);
if (IS_ERR(drvdata->pclk))
- return -ENODEV;
+ return PTR_ERR(drvdata->pclk);

/*
* Map the device base for dynamic-replicator, which has been
@@ -296,8 +296,6 @@ static int replicator_probe(struct device *dev, struct resource *res)
out_disable_clk:
if (ret && !IS_ERR_OR_NULL(drvdata->atclk))
clk_disable_unprepare(drvdata->atclk);
- if (ret && !IS_ERR_OR_NULL(drvdata->pclk))
- clk_disable_unprepare(drvdata->pclk);
return ret;
}

@@ -335,8 +333,6 @@ static void replicator_platform_remove(struct platform_device *pdev)

replicator_remove(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}

#ifdef CONFIG_PM
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index e45c6c7204b4491e0f879bc7d5d445aa1d3118be..88ee453b2815444a550a2b932b28367eb93336b8 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -851,7 +851,7 @@ static int __stm_probe(struct device *dev, struct resource *res)

drvdata->pclk = coresight_get_enable_apb_pclk(dev);
if (IS_ERR(drvdata->pclk))
- return -ENODEV;
+ return PTR_ERR(drvdata->pclk);
dev_set_drvdata(dev, drvdata);

base = devm_ioremap_resource(dev, res);
@@ -1033,8 +1033,6 @@ static void stm_platform_remove(struct platform_device *pdev)

__stm_remove(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}

#ifdef CONFIG_ACPI
diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
index 0b5e7635a084d226619e69189a2ecbaff754ec43..e867198b03e82892da7312c9dc1c69676602c598 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-core.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
@@ -991,7 +991,7 @@ static int tmc_platform_probe(struct platform_device *pdev)

drvdata->pclk = coresight_get_enable_apb_pclk(&pdev->dev);
if (IS_ERR(drvdata->pclk))
- return -ENODEV;
+ return PTR_ERR(drvdata->pclk);

dev_set_drvdata(&pdev->dev, drvdata);
pm_runtime_get_noresume(&pdev->dev);
@@ -1015,8 +1015,6 @@ static void tmc_platform_remove(struct platform_device *pdev)

__tmc_remove(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}

#ifdef CONFIG_PM
diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
index 3e01592884280819c16398cbb5e09cbaee5d3efb..b2559c6fac6d2f02e0038e583cd324d7165c5aee 100644
--- a/drivers/hwtracing/coresight/coresight-tpiu.c
+++ b/drivers/hwtracing/coresight/coresight-tpiu.c
@@ -153,7 +153,7 @@ static int __tpiu_probe(struct device *dev, struct resource *res)

drvdata->pclk = coresight_get_enable_apb_pclk(dev);
if (IS_ERR(drvdata->pclk))
- return -ENODEV;
+ return PTR_ERR(drvdata->pclk);
dev_set_drvdata(dev, drvdata);

/* Validity for the resource is already checked by the AMBA core */
@@ -293,8 +293,6 @@ static void tpiu_platform_remove(struct platform_device *pdev)

__tpiu_remove(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- if (!IS_ERR_OR_NULL(drvdata->pclk))
- clk_put(drvdata->pclk);
}

#ifdef CONFIG_ACPI
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 4ac65c68bbf44b98db22c3dad2d83a224ce5278e..dd2b4cc7a2b70cf060a3207548fe80e3824c489f 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -480,26 +480,16 @@ static inline bool is_coresight_device(void __iomem *base)
* Returns:
*
* clk - Clock is found and enabled
- * NULL - clock is not found
* ERROR - Clock is found but failed to enable
*/
static inline struct clk *coresight_get_enable_apb_pclk(struct device *dev)
{
struct clk *pclk;
- int ret;

- pclk = clk_get(dev, "apb_pclk");
- if (IS_ERR(pclk)) {
- pclk = clk_get(dev, "apb");
- if (IS_ERR(pclk))
- return NULL;
- }
+ pclk = devm_clk_get_enabled(dev, "apb_pclk");
+ if (IS_ERR(pclk))
+ pclk = devm_clk_get_enabled(dev, "apb");

- ret = clk_prepare_enable(pclk);
- if (ret) {
- clk_put(pclk);
- return ERR_PTR(ret);
- }
return pclk;
}


--
2.34.1