On Wednesday, 2018-03-07 13:47:03 -0600, Gustavo A. R. Silva wrote:
> In preparation to enabling -Wvla, remove VLA and replace it
> with a fixed-length array instead. Also, remove variable 'len'.
> 
> Notice that no new IDs have been added in seven years.
> 
> Signed-off-by: Gustavo A. R. Silva <gust...@embeddedor.com>
> ---
>  drivers/video/fbdev/via/via_aux_vt1636.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/video/fbdev/via/via_aux_vt1636.c 
> b/drivers/video/fbdev/via/via_aux_vt1636.c
> index 9e015c1..d6273a4 100644
> --- a/drivers/video/fbdev/via/via_aux_vt1636.c
> +++ b/drivers/video/fbdev/via/via_aux_vt1636.c
> @@ -35,10 +35,10 @@ void via_aux_vt1636_probe(struct via_aux_bus *bus)
>               .addr   =       0x40,
>               .name   =       name};
>       /* check vendor id and device id */
> -     const u8 id[] = {0x06, 0x11, 0x45, 0x33}, len = ARRAY_SIZE(id);
> -     u8 tmp[len];
> +     const u8 id[4] = {0x06, 0x11, 0x45, 0x33};
> +     u8 tmp[4];
>  
> -     if (!via_aux_read(&drv, 0x00, tmp, len) || memcmp(id, tmp, len))
> +     if (!via_aux_read(&drv, 0x00, tmp, 4) || memcmp(id, tmp, 4))

I would recommend keeping ARRAY_SIZE(); even if nothing's been added in
a while, it's still clearer in the code if we can see where these `4`
come from.

Something like this instead?
----8<----
@@ -35,10 +35,10 @@ void via_aux_vt1636_probe(struct via_aux_bus *bus)
                .addr   =       0x40,
                .name   =       name};
        /* check vendor id and device id */
-       const u8 id[] = {0x06, 0x11, 0x45, 0x33}, len = ARRAY_SIZE(id);
-       u8 tmp[len];
+       const u8 id[] = {0x06, 0x11, 0x45, 0x33};
+       u8 tmp[ARRAY_SIZE(id)];
 
-       if (!via_aux_read(&drv, 0x00, tmp, len) || memcmp(id, tmp, len))
+       if (!via_aux_read(&drv, 0x00, tmp, ARRAY_SIZE(id)) || memcmp(id, tmp, 
ARRAY_SIZE(id)))
                return;
 
        printk(KERN_INFO "viafb: Found %s\n", name);
---->8----

Note that sizeof is evaluated a compile time, so `u8 tmp[ARRAY_SIZE(id)]`
is *not* a VLA. All that's needed was to remove `len` :)

>               return;
>  
>       printk(KERN_INFO "viafb: Found %s\n", name);
> -- 
> 2.7.4
> 
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