counter: fix an IS_ERR() vs NULL bug

There are 8 callers for devm_counter_alloc() and they all check for NULL
instead of error pointers.  I think NULL is the better thing to return
for allocation functions so update counter_alloc() and devm_counter_alloc()
to return NULL instead of error pointers.

Fixes: c18e2760308e ("counter: Provide alternative counter registration functions")
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20220111173243.GA2192@kili
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/counter/counter-core.c b/drivers/counter/counter-core.c
index 7e0957e..869894b 100644 (file)
--- a/drivers/counter/counter-core.c
+++ b/drivers/counter/counter-core.c
@@ -90,10 +90,8 @@ struct counter_device *counter_alloc(size_t sizeof_priv)
        int err;
 
        ch = kzalloc(sizeof(*ch) + sizeof_priv, GFP_KERNEL);
-       if (!ch) {
-               err = -ENOMEM;
-               goto err_alloc_ch;
-       }
+       if (!ch)
+               return NULL;
 
        counter = &ch->counter;
        dev = &counter->dev;
@@ -123,9 +121,8 @@ err_chrdev_add:
 err_ida_alloc:
 
        kfree(ch);
-err_alloc_ch:
 
-       return ERR_PTR(err);
+       return NULL;
 }
 EXPORT_SYMBOL_GPL(counter_alloc);
 
@@ -208,12 +205,12 @@ struct counter_device *devm_counter_alloc(struct device *dev, size_t sizeof_priv
        int err;
 
        counter = counter_alloc(sizeof_priv);
-       if (IS_ERR(counter))
-               return counter;
+       if (!counter)
+               return NULL;
 
        err = devm_add_action_or_reset(dev, devm_counter_put, counter);
        if (err < 0)
-               return ERR_PTR(err);
+               return NULL;
 
        return counter;
 }