In commit 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()") PM runtime calls are removed from cti_enable_hw/cti_disable_hw. When enabling CTI by writing enable sysfs node, clock for accessing CTI register won't be enabled. Device will crash due to register access issue. Add PM runtime call in enable_store to fix this issue. Signed-off-by: Mao Jinlong <quic_jinlmao@xxxxxxxxxxx> --- drivers/hwtracing/coresight/coresight-cti-sysfs.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c index 6d59c815ecf5..b1ed424ae043 100644 --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c @@ -108,10 +108,17 @@ static ssize_t enable_store(struct device *dev, if (ret) return ret; - if (val) + if (val) { + ret = pm_runtime_resume_and_get(dev->parent); + if (ret) + return ret; ret = cti_enable(drvdata->csdev); - else + if (ret) + pm_runtime_put(dev->parent); + } else { ret = cti_disable(drvdata->csdev); + pm_runtime_put(dev->parent); + } if (ret) return ret; return size; -- 2.17.1