Re: [PATCH v2] gpio: mockup: no need to check return value of debugfs_create functions

[Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>]

czw., 20 cze 2019 o 09:25 Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> napisał(a):
>
> When calling debugfs functions, there is no need to ever check the
> return value.  The function can work or not, but the code logic should
> never do something different based on this.
>
> Cc: Bamvor Jian Zhang <bamv2005@xxxxxxxxx>
> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
> Cc: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
> Cc: linux-gpio@xxxxxxxxxxxxxxx
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
> v2: fix build warning found by kbuild
>     fix build error found by kbuild.  Did I even build this thing
>     myself???
>
>  drivers/gpio/gpio-mockup.c | 18 ++++--------------
>  1 file changed, 4 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
> index b6a4efce7c92..135dac099d1e 100644
> --- a/drivers/gpio/gpio-mockup.c
> +++ b/drivers/gpio/gpio-mockup.c
> @@ -315,7 +315,6 @@ static void gpio_mockup_debugfs_setup(struct device *dev,
>                                       struct gpio_mockup_chip *chip)
>  {
>         struct gpio_mockup_dbgfs_private *priv;
> -       struct dentry *evfile;
>         struct gpio_chip *gc;
>         const char *devname;
>         char *name;
> @@ -325,32 +324,25 @@ static void gpio_mockup_debugfs_setup(struct device *dev,
>         devname = dev_name(&gc->gpiodev->dev);
>
>         chip->dbg_dir = debugfs_create_dir(devname, gpio_mockup_dbg_dir);
> -       if (IS_ERR_OR_NULL(chip->dbg_dir))
> -               goto err;
>
>         for (i = 0; i < gc->ngpio; i++) {
>                 name = devm_kasprintf(dev, GFP_KERNEL, "%d", i);
>                 if (!name)
> -                       goto err;
> +                       return;
>
>                 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>                 if (!priv)
> -                       goto err;
> +                       return;
>
>                 priv->chip = chip;
>                 priv->offset = i;
>                 priv->desc = &gc->gpiodev->descs[i];
>
> -               evfile = debugfs_create_file(name, 0200, chip->dbg_dir, priv,
> -                                            &gpio_mockup_debugfs_ops);
> -               if (IS_ERR_OR_NULL(evfile))
> -                       goto err;
> +               debugfs_create_file(name, 0200, chip->dbg_dir, priv,
> +                                   &gpio_mockup_debugfs_ops);
>         }
>
>         return;
> -
> -err:
> -       dev_err(dev, "error creating debugfs files\n");
>  }
>
>  static int gpio_mockup_name_lines(struct device *dev,
> @@ -501,8 +493,6 @@ static int __init gpio_mockup_init(void)
>         }
>
>         gpio_mockup_dbg_dir = debugfs_create_dir("gpio-mockup", NULL);
> -       if (IS_ERR_OR_NULL(gpio_mockup_dbg_dir))
> -               gpio_mockup_err("error creating debugfs directory\n");
>
>         err = platform_driver_register(&gpio_mockup_driver);
>         if (err) {
> --
> 2.22.0
>

Shouldn't this patch also make the driver unconditionally call
gpio_mockup_debugfs_setup() at line 450?

Bart