mailbox: mailbox-test: Use more consistent format for calling copy_from_user()

While we're at it, ensure copy-to location is NULL'ed in the error path.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
index dc11bbf27274380ecf60b55491193363d947e5c0..5f4b439fd45abb12226eef0256ac6db76606a254 100644 (file)
--- a/drivers/mailbox/mailbox-test.c
+++ b/drivers/mailbox/mailbox-test.c
@@ -46,7 +46,6 @@ static ssize_t mbox_test_signal_write(struct file *filp,
                                       size_t count, loff_t *ppos)
 {
        struct mbox_test_device *tdev = filp->private_data;
-       int ret;
 
        if (!tdev->tx_channel) {
                dev_err(tdev->dev, "Channel cannot do Tx\n");
@@ -64,13 +63,13 @@ static ssize_t mbox_test_signal_write(struct file *filp,
        if (!tdev->signal)
                return -ENOMEM;
 
-       ret = copy_from_user(tdev->signal, userbuf, count);
-       if (ret) {
+       if (copy_from_user(tdev->signal, userbuf, count)) {
                kfree(tdev->signal);
+               tdev->signal = NULL;
                return -EFAULT;
        }
 
-       return ret < 0 ? ret : count;
+       return count;
 }
 
 static const struct file_operations mbox_test_signal_ops = {