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Diffstat (limited to 'drivers')
-rw-r--r--drivers/mailbox/mailbox-test.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
index 51e62817f243..c4a705c30331 100644
--- a/drivers/mailbox/mailbox-test.c
+++ b/drivers/mailbox/mailbox-test.c
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/mailbox_client.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/poll.h>
@@ -39,6 +40,7 @@ struct mbox_test_device {
char *signal;
char *message;
spinlock_t lock;
+ struct mutex mutex;
wait_queue_head_t waitq;
struct fasync_struct *async_queue;
struct dentry *root_debugfs_dir;
@@ -111,6 +113,8 @@ static ssize_t mbox_test_message_write(struct file *filp,
return -EINVAL;
}
+ mutex_lock(&tdev->mutex);
+
tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL);
if (!tdev->message)
return -ENOMEM;
@@ -145,6 +149,8 @@ out:
kfree(tdev->message);
tdev->signal = NULL;
+ mutex_unlock(&tdev->mutex);
+
return ret < 0 ? ret : count;
}
@@ -393,6 +399,7 @@ static int mbox_test_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, tdev);
spin_lock_init(&tdev->lock);
+ mutex_init(&tdev->mutex);
if (tdev->rx_channel) {
tdev->rx_buffer = devm_kzalloc(&pdev->dev,