This is a note to let you know that I've just added the patch titled coresight: cti: Add PM runtime call in enable_store to the 6.2-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: coresight-cti-add-pm-runtime-call-in-enable_store.patch and it can be found in the queue-6.2 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 9306ff20af7537ac62dd73fbed57768f48cedf70 Author: Mao Jinlong <quic_jinlmao@xxxxxxxxxxx> Date: Tue Jan 10 11:07:35 2023 +0000 coresight: cti: Add PM runtime call in enable_store [ Upstream commit eff674a9b86a6ffdd10c3af3863545acf7f1ce4f ] 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. Fixes: 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()") Signed-off-by: Mao Jinlong <quic_jinlmao@xxxxxxxxxxx> [Change to only call pm_runtime_put if a disable happened] Tested-by: Jinlong Mao <quic_jinlmao@xxxxxxxxxxx> Signed-off-by: James Clark <james.clark@xxxxxxx> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Link: https://lore.kernel.org/r/20230110110736.2709917-3-james.clark@xxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c index 6d59c815ecf5e..71e7a8266bb32 100644 --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c @@ -108,10 +108,19 @@ 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); + if (!ret) + pm_runtime_put(dev->parent); + } + if (ret) return ret; return size;