Re: [bug report] gpio: reflect base and ngpio into gpio_device

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Thu, Oct 12, 2017 at 11:08 PM, Dan Carpenter
<dan.carpenter@xxxxxxxxxx> wrote:

> drivers/gpio/gpiolib.c
>   2345  int gpiod_direction_output(struct gpio_desc *desc, int value)
>   2346  {
>   2347          struct gpio_chip *gc = desc->gdev->chip;
>   2348          int ret;
>   2349
>   2350          VALIDATE_DESC(desc);
>
> I'm not a huge fan of the VALIDATE_DESC() macro because it has hidden
> returns in it...

It was the best I could come up with. It's either this macro, or duplicate
the same code all over the place which would be a mess.

This is the lesser evil IMO, if you have better ideas, .... share them. :)
(Duplicating the descriptor check at every site is not a good idea.
Static inlines cannot be used, because we need to return if the descriptor
is invalid. You get the picture...)

>  But actually it's the earlier desc->gdev->chip
> dereference which is wrong.  We should probably move that below the
> checks for NULL.

True. I bet there is already a patch in my inbox ;)

Yours,
Linus Walleij
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html