Re: [PATCH] staging: wfx: avoid compiler warning on empty array

[Jerome Pouiller]

On Wednesday 29 April 2020 16:21:09 CEST Arnd Bergmann wrote:
> 
> When CONFIG_OF is disabled, gcc-9 produces a warning about the
> wfx_sdio_of_match[] array having a declaration without a dimension:
> 
> drivers/staging/wfx/bus_sdio.c:159:34: error: array 'wfx_sdio_of_match' assumed to have one element [-Werror]
>   159 | static const struct of_device_id wfx_sdio_of_match[];
>       |                                  ^~~~~~~~~~~~~~~~~
> 
> Move the proper declaration up and out of the #ifdef instead.
> 
> Fixes: a7a91ca5a23d ("staging: wfx: add infrastructure for new driver")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>  drivers/staging/wfx/bus_sdio.c | 19 ++++++++-----------
>  1 file changed, 8 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/staging/wfx/bus_sdio.c b/drivers/staging/wfx/bus_sdio.c
> index dedc3ff58d3e..c2e4bd1e3b0a 100644
> --- a/drivers/staging/wfx/bus_sdio.c
> +++ b/drivers/staging/wfx/bus_sdio.c
> @@ -156,7 +156,13 @@ static const struct hwbus_ops wfx_sdio_hwbus_ops = {
>         .align_size             = wfx_sdio_align_size,
>  };
> 
> -static const struct of_device_id wfx_sdio_of_match[];
> +static const struct of_device_id wfx_sdio_of_match[] = {
> +       { .compatible = "silabs,wfx-sdio" },
> +       { .compatible = "silabs,wf200" },
> +       { },
> +};
> +MODULE_DEVICE_TABLE(of, wfx_sdio_of_match);
I suggest to keep the '#ifdef CONFIG_OF' around this definition. If
CONFIG_OF is undefined, of_match_ptr() and of_match_node() will be NULL
and it should compile.


> +
>  static int wfx_sdio_probe(struct sdio_func *func,
>                           const struct sdio_device_id *id)
>  {
> @@ -248,15 +254,6 @@ static const struct sdio_device_id wfx_sdio_ids[] = {
>  };
>  MODULE_DEVICE_TABLE(sdio, wfx_sdio_ids);
> 
> -#ifdef CONFIG_OF
> -static const struct of_device_id wfx_sdio_of_match[] = {
> -       { .compatible = "silabs,wfx-sdio" },
> -       { .compatible = "silabs,wf200" },
> -       { },
> -};
> -MODULE_DEVICE_TABLE(of, wfx_sdio_of_match);
> -#endif
> -
>  struct sdio_driver wfx_sdio_driver = {
>         .name = "wfx-sdio",
>         .id_table = wfx_sdio_ids,
> @@ -264,6 +261,6 @@ struct sdio_driver wfx_sdio_driver = {
>         .remove = wfx_sdio_remove,
>         .drv = {
>                 .owner = THIS_MODULE,
> -               .of_match_table = of_match_ptr(wfx_sdio_of_match),
> +               .of_match_table = wfx_sdio_of_match,

... and obviously keep of_match_ptr() here.

>         }
>  };


-- 
Jérôme Pouiller