From 2d94e5224e81c58986a8cf44a3bf4830ce5cb96e Mon Sep 17 00:00:00 2001 From: Srinivas Pandruvada Date: Thu, 7 May 2015 14:26:34 -0700 Subject: [PATCH] HID: hid-sensor-hub: Fix debug lock warning When CONFIG_DEBUG_LOCK_ALLOC is defined, mutex magic is compared and warned for (l->magic != l), here l is the address of mutex pointer. In hid-sensor-hub as part of hsdev creation, a per hsdev mutex is initialized during MFD cell creation. This hsdev, which contains, mutex is part of platform data for the a cell. But platform_data is copied in platform_device_add_data() in platform.c. This copy will copy the whole hsdev structure including mutex. But once copied the magic will no longer match. So when client driver call sensor_hub_input_attr_get_raw_value, this will trigger mutex warning. So to avoid this allocate mutex dynamically. This will be same even after copy. Signed-off-by: Srinivas Pandruvada Signed-off-by: Jiri Kosina --- drivers/hid/hid-sensor-hub.c | 13 ++++++++++--- include/linux/hid-sensor-hub.h | 4 ++-- 2 files changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/hid/hid-sensor-hub.c b/drivers/hid/hid-sensor-hub.c index c3f6f1e311ea..090a1ba0abb6 100644 --- a/drivers/hid/hid-sensor-hub.c +++ b/drivers/hid/hid-sensor-hub.c @@ -294,7 +294,7 @@ int sensor_hub_input_attr_get_raw_value(struct hid_sensor_hub_device *hsdev, if (!report) return -EINVAL; - mutex_lock(&hsdev->mutex); + mutex_lock(hsdev->mutex_ptr); if (flag == SENSOR_HUB_SYNC) { memset(&hsdev->pending, 0, sizeof(hsdev->pending)); init_completion(&hsdev->pending.ready); @@ -328,7 +328,7 @@ int sensor_hub_input_attr_get_raw_value(struct hid_sensor_hub_device *hsdev, kfree(hsdev->pending.raw_data); hsdev->pending.status = false; } - mutex_unlock(&hsdev->mutex); + mutex_unlock(hsdev->mutex_ptr); return ret_val; } @@ -667,7 +667,14 @@ static int sensor_hub_probe(struct hid_device *hdev, hsdev->vendor_id = hdev->vendor; hsdev->product_id = hdev->product; hsdev->usage = collection->usage; - mutex_init(&hsdev->mutex); + hsdev->mutex_ptr = devm_kzalloc(&hdev->dev, + sizeof(struct mutex), + GFP_KERNEL); + if (!hsdev->mutex_ptr) { + ret = -ENOMEM; + goto err_stop_hw; + } + mutex_init(hsdev->mutex_ptr); hsdev->start_collection_index = i; if (last_hsdev) last_hsdev->end_collection_index = i; diff --git a/include/linux/hid-sensor-hub.h b/include/linux/hid-sensor-hub.h index 0408421d885f..0042bf330b99 100644 --- a/include/linux/hid-sensor-hub.h +++ b/include/linux/hid-sensor-hub.h @@ -74,7 +74,7 @@ struct sensor_hub_pending { * @usage: Usage id for this hub device instance. * @start_collection_index: Starting index for a phy type collection * @end_collection_index: Last index for a phy type collection - * @mutex: synchronizing mutex. + * @mutex_ptr: synchronizing mutex pointer. * @pending: Holds information of pending sync read request. */ struct hid_sensor_hub_device { @@ -84,7 +84,7 @@ struct hid_sensor_hub_device { u32 usage; int start_collection_index; int end_collection_index; - struct mutex mutex; + struct mutex *mutex_ptr; struct sensor_hub_pending pending; }; -- 2.20.1