Re: [PATCH v5 02/10] pinctrl: generic: Add macros to unpack properties

From: Linus Walleij
Date: Fri Apr 28 2017 - 04:16:39 EST


On Thu, Apr 27, 2017 at 10:19 AM, Jacopo Mondi
<jacopo+renesas@xxxxxxxxxx> wrote:

> Add PIN_CONF_UNPACK_PARAM and PIN_CONF_UNPACK_ARGS macros useful to
> unpack generic properties and their arguments
>
> Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>

(...)

/*
* Helpful configuration macro to be used in tables etc.

Then this should say "macros" rather than "macro".

> -#define PIN_CONF_PACKED(p, a) ((a << 8) | ((unsigned long) p & 0xffUL))
> +#define PIN_CONF_PACKED(p, a) (((a) << 8) | ((unsigned long) (p) & 0xffUL))

Also adding some extra parantheses I see.

> +#define PIN_CONF_UNPACK_PARAM(c) ((c) & 0xffUL)
> +#define PIN_CONF_UNPACK_ARGS(c) ((c) >> 8)

But why.

I have these two static inlines just below your new macros:

static inline enum pin_config_param pinconf_to_config_param(unsigned
long config)
{
return (enum pin_config_param) (config & 0xffUL);
}

static inline u32 pinconf_to_config_argument(unsigned long config)
{
return (u32) ((config >> 8) & 0xffffffUL);
}

Why can't you use this in your code instead of macros?

We generally prefer static inlines over macros because they are easier
to read.

Yours,
Linus Walleij