On Tue, Nov 18, 2014 at 10:18:44PM +0100, Willy Tarreau wrote:
> On Tue, Nov 18, 2014 at 09:56:09PM +0100, Mariusz Gorski wrote:
> > Avoid values comparison and use a macro instead that checks
> > whether module param has been set by the user to some value
> > at loading time.
> >
> > Signed-off-by: Mariusz Gorski <marius.gorski@xxxxxxxxx>
> > ---
> > drivers/staging/panel/panel.c | 88 ++++++++++++++++++++++---------------------
> > 1 file changed, 45 insertions(+), 43 deletions(-)
> >
> > diff --git a/drivers/staging/panel/panel.c b/drivers/staging/panel/panel.c
> > index 1b4a211..97fc4ca 100644
> > --- a/drivers/staging/panel/panel.c
> > +++ b/drivers/staging/panel/panel.c
> > @@ -135,6 +135,8 @@
> >
> > #define NOT_SET -1
> >
> > +#define IS_NOT_SET(x) (x == NOT_SET)
> > +
> > /* macros to simplify use of the parallel port */
> > #define r_ctr(x) (parport_read_control((x)->port))
> > #define r_dtr(x) (parport_read_data((x)->port))
> > @@ -1411,29 +1413,29 @@ static void lcd_init(void)
> > switch (lcd_type) {
> > case LCD_TYPE_OLD:
> > /* parallel mode, 8 bits */
> > - if (lcd_proto < 0)
> > + if (IS_NOT_SET(lcd_proto))
> > lcd_proto = LCD_PROTO_PARALLEL;
> > - if (lcd_charset < 0)
> > + if (IS_NOT_SET(lcd_charset))
> > lcd_charset = LCD_CHARSET_NORMAL;
> > if (lcd_e_pin == PIN_NOT_SET)
> > lcd_e_pin = PIN_STROBE;
> > if (lcd_rs_pin == PIN_NOT_SET)
> > lcd_rs_pin = PIN_AUTOLF;
> >
> > - if (lcd_width < 0)
> > + if (IS_NOT_SET(lcd_width))
> > lcd_width = 40;
> (...)
>
> I'm not convinced at all by the increased readability of this one.
> To me it adds obfuscation since I have to look for the macro definition
> to see how it checks whether the type is set or not.
>
> I think you'd rather simply open-code the macro here and keep the natural
> comparison. The fields were already initialized to the NOT_SET value, better
> check agaist the same value here especially since it matches other tests as
> well. That would give :
>
> - if (lcd_proto < 0)
> + if (lcd_proto == NOT_SET)
> lcd_proto = LCD_PROTO_PARALLEL;
>
> etc... To me it's more readable.
>
> Willy
>
Hmm ok maybe you're right, maybe I've tried to hide too much here.
"x == NOT_SET" hides already enough ;) I'll fix that.
Thanks,
Mariusz
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
